Advanced Ion Exchange Membranes And Applications Thereof

Abstract

Improved performance ion exchange membranes for use in PEM, AEM and DMFC fuel cells, buffered fuel cells, hydrolysis, other applications comprise a molecular matrix of homopolymers, di-monomer, heteropolymers, copolymers, or block-polymers of fluorocarbon and hydrocarbon compounds combined with (i) skeletal support grid to improve durability, handling, reduce membrane swelling, and sequester dopants and nanoparticles from leakage; (ii) microporous membrane formed using a sacrificial filler process enhancing conductivity and limiting fuel crossover; (iii) hetero-ionomeric matrix of two-or-more membrane-bound acids e.g. sulphonic and phosphonic acid expanding usable range; (iv) permanent fillers enhancing conductivity and porosity including nanoparticles, metal-oxides, zeolites, silicates, GOs, CNTs, MOFs, POSS, and others; (v) ionic liquid doping to enhance membrane conductivity; (vi) membrane nanocoating preventing H.sub.2O.sub.2 diffusion; and/or (vii) catalytic nanocoating with metals, metal-oxides, and MOFs preventing atmospheric toxin catalyst poisoning. Combined with a heterogenous GDL, the IEM is integrated into iBFC power blade and energy bank applications.

Claims

1. An ion exchange membrane comprising an electrically conductive polymer matrix capable of conducting either cations or anions but not both; where the polymer contains a hydrophobic polymeric backbone providing structure and mechanical support to the membrane; where hydrophilic functional groups are attached either directly onto the backbone or indirectly at the terminus of a sidechain pendant molecule bonded or grafted onto the polymer mainchain; where the functional groups comprise a membrane bound acid or base readily ionized into an immobile anionic or cationic ionomer, by which mobile charged ions such as protons, hydronium, or hydroxide ions may attach and detach to facilitate hopping conduction through the polymeric matrix; where the membrane contains a skeletal matrix of inert pillars circumscribing and subdividing the conductive ionomeric membrane into panes; and where the skeletal matrix chemically bonds to the panes of conductive ionomeric polymers forming a unitary ion conduction membrane having both mechanical strength and electrical conductivity.

2. The apparatus of claim 1 where the membrane is an proton exchange membrane, the ionomers comprise immobile anions, and where the transported charge comprises hydrogen and hydronium ions.

3. The apparatus of claim 1 where the membrane contains a membrane acid of sulphonic or phosphonic acid.

4. The apparatus of claim 1 where the acid group is attached to the terminus of a sidechain pendant bonded to the mainchain.

5. The apparatus of claim 1 where the conductive membrane comprises a fluorocarbon homopolymer such as PFSA or heteropolymer such as PFSA-PTFE.

6. The apparatus of claim 1 where the conductive membrane comprises a functionalized hydrocarbon polymer such as a blend of arylene, ether, ketone, nitrile, sulfone,

7. The apparatus of claim 6 where the hydrocarbon polymer is functionalized by sulphonic, phosphonic, or phosphoric acids.

8. The apparatus of claim 1 where the membrane is coated with PTFE nanospheres.

9. The apparatus of claim 1 where the skeletal pillars comprise an inert hydrophobic material.

10. The apparatus of claim 9 where the skeletal pillar is bonded to the ionomeric polymer by an intervening linking compound such as a molecular glue or polyvinyl alcohol.

11. The apparatus of claim 9 where the skeletal pillar is co-molded with the ionomeric polymer, i.e. polymerized concurrently.

12. The apparatus of claim 9 where the skeletal pillar of claim 10 has a roughened surface from a chemical or radiation pretreatment before being molded with the ionomeric polymer.

13. The apparatus of claim 1 where the skeletal matrix is defined by a casting mold with a mold chaise inserted into the mold cavity to limit where the skeletal matrix is formed.

14. The apparatus of claim 13 where the mold compound filling the skeletal regions includes a combination of organic monomers, cross-linkers, and strengthening fillers such as carbon fiber.

15. The apparatus of claim 14 where the cross linkers invoke complete polymerization of the skeletal support

16. The apparatus of claim 15 where the remaining unoccupied space in the mold cavity after the mold chaise insert has been removed is filled with organic monomers and cross-linkers during which polymerization of the ionomeric polymer bonds to the fully polymerized skeleton.

17. The apparatus of claim 16 where the cross linkers cause only partially polymerize the skeletal support.

18. The apparatus of claim 17 where the remaining unoccupied space in the mold cavity after the mold chaise insert has been removed is filled with organic monomers and cross-linkers during which polymerization of the ionomeric polymer bonds and copolymerizes the partially polymerized skeleton.

19. The apparatus of claim 1 where an ion exchange membrane where the skeletal support matrix includes wide and narrow pillars, where the sheet of multiple ion exchange membranes has been singulated along the wider pillars.

20. An ion exchange membrane comprising an electrically conductive polymer matrix capable of conducting either cations or anions but not both; where the polymer contains a hydrophobic polymeric backbone providing structure and mechanical support to the membrane; where hydrophilic functional groups are attached either directly onto the backbone or indirectly at the terminus of a sidechain pendant molecule bonded or grafted onto the polymer mainchain; where the functional groups comprise a membrane bound acid or base readily ionized into an immobile anionic or cationic ionomer, by which mobile charged ions such as protons, hydronium, or hydroxide ions may attach and detach to facilitate hopping conduction through the polymeric matrix; where the membrane contains a sacrificial filler molecule such as sugar after molding.

21. The apparatus of claim 22 where the sacrificial filler is no longer present in the membrane.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0533] FIG. 1. Mechanistic schematic of hydrogen fuel cell electrochemistry.

[0534] FIG. 2. Pseudo-structural model and chemical formula for PFSA.

[0535] FIG. 3. Conduction mechanisms in ion exchange membranes.

[0536] FIG. 4A. Comparison of chemical formulas for commercial PFSA ionomers and PTFE.

[0537] FIG. 4B. Generalized and schematic representations of PFSA ionomer, pendant, and backbone

[0538] FIG. 5. Grafting of PFSA sidechains onto PTFE backbone.

[0539] FIG. 6. Charge transport models for alkali, MCFC, PAFC, and SOFC fuel cells showing ion conduction in electrolyte.

[0540] FIG. 7. Diagram of fuel cell components comprising a membrane electrode assembly (MEA).

[0541] FIG. 8A. Lumped element schematic representation of a fuel cell.

[0542] FIG. 8B. Simplified lumped element schematic representation of a fuel cell.

[0543] FIG. 9A. Schematic of operation of fuel cell membrane electrode assembly depicting mechanisms involving water.

[0544] FIG. 9B. Schematic representation of function of gas diffusion layer (GDL) in a PEM fuel cell.

[0545] FIG. 10. Exemplary curves of conventional PEM hydrogen fuel cell voltage V.sub.FC at 70 C. as a function of current density I/A for various levels of relative humidity RH.

[0546] FIG. 11. Exemplary curves of conventional PEM hydrogen fuel cell voltage V.sub.FC at 90 C. as a function of current density I/A for various levels of relative humidity RH.

[0547] FIG. 12. Exemplary curves of conventional PEM hydrogen fuel cell voltage V.sub.FC at 70 C. as a function of relative humidity RH for various levels of current density I/A.

[0548] FIG. 13. Exemplary curves of conventional PEM hydrogen fuel cell specific resistance R.sub.FC A at 70 C. as a function of current density I/A for various levels of relative humidity RH.

[0549] FIG. 14. Current dependence of voltage for a 4s1p fuel cell stack including resistance calculations.

[0550] FIG. 15A. Electrical resistance as a function of ion exchange membrane thickness.

[0551] FIG. 15B. Graph representing the cross sectional vertical displacement, i.e. sag, of a polymeric membrane as a function of width and film thickness.

[0552] FIG. 16. Graph illustrating endoskeleton reduces membrane sag.

[0553] FIG. 17. Illustration of membrane swelling with and without endoskeletal support.

[0554] FIG. 18A. Top view of membrane frame.

[0555] FIG. 18B. Top view of membrane frame including exoskeleton and membrane matrix.

[0556] FIG. 18C. Top view of membrane matrix after frame removal.

[0557] FIG. 19A. Process flow options for fabricating an MEA3 ion exchange membrane.

[0558] FIG. 19B. Process flow options for fabricating an MEA5 ion exchange membrane from a MEA3 CCM.

[0559] FIG. 20. Cross sectional comparison of membrane matrix with symmetric and offset frames.

[0560] FIG. 21. Cross section of mold forming membrane matrix frame and skeleton.

[0561] FIG. 22. Cross section of mold forming fiber reinforced membrane matrix frame and skeleton.

[0562] FIG. 23. Cross section of ion exchange membrane comparing bulk and surface ionomer conduction.

[0563] FIG. 24. Top view of membrane matrix before and after IEM singulation.

[0564] FIG. 25. Top view of membrane matrix illustrating frame cut lines.

[0565] FIG. 26. Top view of membrane matrix illustrating IEM cut lines.

[0566] FIG. 27. Top and side view of membrane matrix with offset frame.

[0567] FIG. 28. Side views of membrane matrix with offset frame with and without tie bar.

[0568] FIG. 29. Side view of empty mold chamber for IEM fabrication.

[0569] FIG. 30. Side view of mold chamber with mold chase for fabricating IEM membrane matrix with offset frame.

[0570] FIG. 31. Side view of mold chamber with mold chase for offset frame and skeleton fabrication loaded with mold compound.

[0571] FIG. 32. Side view of mold chamber with mold chase for offset frame and skeleton fabrication after polymerization.

[0572] FIG. 33. Side view of inverted of membrane frame and skeleton in empty mold chamber.

[0573] FIG. 34. Side view of step loading of ionomer into mold chamber with inverted frame and skeleton.

[0574] FIG. 35. Side view of step applying mold cap to ionomer loaded mold.

[0575] FIG. 36. Side view of step pressurizing ionomer loaded mold during polymerization.

[0576] FIG. 37. Side view of step for heat treatment during ionomer polymerization.

[0577] FIG. 38. Side view of anode catalyst coating of membrane.

[0578] FIG. 39. Cross section of fabricated catalyst coated membrane and matrix frame.

[0579] FIG. 40. Side view of step attaching handle to CCM and matrix frame.

[0580] FIG. 41. Side view of membrane during cathode catalyst coating.

[0581] FIG. 42. Cross section of cathode catalyst coated membrane including handle.

[0582] FIG. 43. Cross section of cathode catalyst coated of membrane with handle not shown.

[0583] FIG. 44. Side view of step attaching cathode GDL to CCM and matrix frame.

[0584] FIG. 45. Cross section of CCM with cathode GDL and matrix frame.

[0585] FIG. 46. Side view of step attaching anode GDL to CCM and matrix frame.

[0586] FIG. 47. Side view of step during laser singulation of MEA5 IEM.

[0587] FIG. 48. Cross section of singulated MEA5 five-layer IEM.

[0588] FIG. 49. Cross section of fabricated MEA7 seven-layer IEM.

[0589] FIG. 50. Top and side views of matrix frame and skeleton.

[0590] FIG. 51. Top and side views of matrix frame and skeleton and ionomeric membrane.

[0591] FIG. 52. Top and side views of matrix frame and skeleton comprising multiple CCM three layer MEA3s.

[0592] FIG. 53. Top and side views of matrix frame and skeleton comprising multiple five layer MEA5s.

[0593] FIG. 54. Top and side views of matrix frame and skeleton comprising multiple five layer MEA5s illustrating singulation laser cut pattern.

[0594] FIG. 55. Top vide and cross section of singulated MEA5 five-layer IEM.

[0595] FIG. 56. Top and side view of membrane matrix with vertically symmetric frame.

[0596] FIG. 57. Cross sections of membrane matrix with symmetric frame with and without tie bar.

[0597] FIG. 58. Side view of mold chamber with multi-piece mold chase.

[0598] FIG. 59. Side view of multi-piece mold chase after polymerization of matrix frame.

[0599] FIG. 60. Side view of multi-piece mold chase after removal of top chase.

[0600] FIG. 61. Side view of multi-piece mold chase after polymerization of skeleton.

[0601] FIG. 62. Side view of multi-piece mold chase after removal of intermediate mold chase and loading of ionomeric monomers.

[0602] FIG. 63. Side view of step pressurizing ionomer loaded mold during polymerization.

[0603] FIG. 64. Side view of step for heat treatment during ionomer polymerization.

[0604] FIG. 65. Side view of step for heat treatment after ionomer polymerization.

[0605] FIG. 66. Side view of step attaching handle to membrane and matrix frame.

[0606] FIG. 67. Cross section of membrane with attached handle prior to catalyst deposition.

[0607] FIG. 68. Side view of anode catalyst coating of membrane.

[0608] FIG. 69. Cross section of anode catalyst coated membrane and matrix frame.

[0609] FIG. 70. Cross section of membrane during cathode catalyst deposition after handle has been removed from anode and attached to cathode side.

[0610] FIG. 71. Side view of fabricated CCM after cathode catalyst coating.

[0611] FIG. 72. Side view of steps attaching cathode and anode GDL to CCM and matrix frame after handle removal.

[0612] FIG. 73. Cross section of matrix of MEA5 five-layer IEMs prior to singulation and frame removal.

[0613] FIG. 74. Cross section of matrix of MEA5 five-layer IEMs illustrating laser cut lines.

[0614] FIG. 75. Cross section of singulated five-layer IEM5.

[0615] FIG. 76. Cross section of singulated seven-layer IEM7.

[0616] FIG. 77A. Process flow for fabrication of CRM comprising PFSA-PVA-PTFE ionomer.

[0617] FIG. 77B. Process flows for fabrication of various exemplary porous membrane IEMs.

[0618] FIG. 78. Photomicrographs and SEMs of IEM fabricated films.

[0619] FIG. 79A. Voltage-current characteristics, aka polarization curves of various CRM films contrasted to Nafion membrane performance.

[0620] FIG. 79B. Power output curves for various thickness CRM membranes versus Nafion membrane performance.

[0621] FIG. 80. Lumped element model of fuel cell showing resistive and polarization losses.

[0622] FIG. 81. Process flows for fabrication of various porous IEM membranes.

[0623] FIG. 82. Photos of exemplary steps in porous PFSA IEM membrane fabrication.

[0624] FIG. 83. Photo of porous exchange membrane.

[0625] FIG. 84. Top view and cross sections of porous exchange membrane.

[0626] FIG. 85A. Voltage-current characteristics, aka polarization curves contrasting porous PEM, CRM PEM, and Nafion membrane performance.

[0627] FIG. 85B. Voltage-current polarization characteristics of measured porous PEM, CRM PEM, and Nafion membrane performance identifying DC parametric data points.

[0628] FIG. 85C. Piecewise linear model of measure PEM voltage-current characteristics, of porous PEM, CRM PEM, and Nafion membrane performance identifying DC parametric data points.

[0629] FIG. 85D. Power output density and power efficiency as a function of power input density comparing porous PEM, CRM PEM, and Nafion membrane performance.

[0630] FIG. 85E. Power loss and power loss density as a function of power input and power input density comparing porous PEM, CRM PEM, and Nafion membrane performance.

[0631] FIG. 85F. Power loss and power loss density as a function of power output and power output density comparing porous PEM, CRM PEM, and Nafion membrane performance.

[0632] FIG. 86. Power output as a function of current density comparing porous PEM, CRM PEM, and Nafion membrane performance.

[0633] FIG. 87A. Cross sectional depiction of a homogenous GDL gas diffusion layer and CCM.

[0634] FIG. 87B. Cross sectional depiction of a bilayer gas diffusion layer comprising a uniform GDL with MPL microporous layer atop CCM.

[0635] FIG. 88. Cross sectional comparison of fuel cell hydration with and without MPL.

[0636] FIG. 89. Photomicrographs of BPP gas channel at various FC screw pressures showing varying degrees of GDL encroachment.

[0637] FIG. 90A. Schematic representation of three-head GDL printer with varying inks of carbon fiber length.

[0638] FIG. 90B. Schematic representation of single-head GDL printer with carbon ink comprising varying a blended mix of carbon fiber lengths.

[0639] FIG. 91. Schematic representation of hGDL heterogenous gas diffusion layer comprising three layer graded GDL with MPL.

[0640] FIG. 92. Schematic representation of hGDL heterogenous gas diffusion layer and CCM illustrating SEMs of three layer graded GDL with MPL.

[0641] FIG. 93. Cross section of MEA7 assembly comprising hGDL with graded porosity.

[0642] FIG. 94. Depiction of hGDL attachment to CCM with and without decal laminated catalyst layer of MPL.

[0643] FIG. 95. Process flow for MEA5 fabrication forming and attaching decal laminated catalyst layer on MPL to sputter coated CCM.

[0644] FIG. 96A. Voltage-current characteristics, aka polarization curves contrasting porous PEM, CRM PEM, and Nafion membrane performance with and without hGDL.

[0645] FIG. 96B. Voltage-current characteristics of measured porous PEM, CRM PEM, and Nafion membrane performance with and without hGDL identifying DC parametric data points.

[0646] FIG. 96C. Piecewise linear model of measure PEM voltage-current characteristics, of porous PEM, CRM PEM, and Nafion membrane performance with and without hGDL identifying DC parametric data points.

[0647] FIG. 96D. Power output density as a function of power input density comparing porous PEM, CRM PEM, and Nafion membrane performance with and without hGDL.

[0648] FIG. 96E. Power efficiency as a function of power input density comparing porous PEM, CRM PEM, and Nafion membrane performance with and without hGDL.

[0649] FIG. 96F. Power loss and power loss density as a function of power input and power input density comparing porous PEM, CRM PEM, and Nafion membrane performance with and without hGDL.

[0650] FIG. 96G. Power loss and power loss density as a function of power output and power output density comparing porous PEM, CRM PEM, and Nafion membrane performance with and without hGDL.

[0651] FIG. 97. Power output as a function of current density comparing porous PEM, CRM PEM, and Nafion membrane performance with and without hGDL.

[0652] FIG. 98. Top view of exemplary assembled stack of MEA7 IEMs highlighting layer thicknesses.

[0653] FIG. 99. Cross sectional comparison of 24V conventional and advanced fuel cells contrasted to lithium ion cell and 4V AFC dimensions.

[0654] FIG. 100. Cross section of seven-layer MEA7 fuel cell assembly depicting TPP tripolar plate with internal temperature sensor.

[0655] FIG. 101. Functional diagram of temperature sensing, feedback, and control of iBFC via a heat exchange and open cathode airflow.

[0656] FIG. 102A. Relationship between fuel cell peak temperature and thermal resistance versus air flow rate for 48 W power dissipation.

[0657] FIG. 102B. Exemplary data points relating fuel cell peak temperature and thermal resistance versus air flow rate.

[0658] FIG. 103. Graph of power loss versus power output of Nafion PEM, CRM PEM+, and porous PEM+fuel cells highlighting air cooling limit.

[0659] FIG. 104. Simplified cross sectional schematic representation comparing (a) a IEM carbon polymer matrix backbones, (b) the carbon polymer matrix including fluorine bonds and resulting electrostatic cloud, and (c) carbon polymer matrix and electrostatic cloud modified by sacrificial filler (after removal).

[0660] FIG. 105. Molecular model of pendant graft depicting (a) pristine polymer, (b) fluorocarbon backbone with exposed carbon graft point, and (c) sidechain pendant grafting ionomer to graft point of carbon backbone.

[0661] FIG. 106. Schematic representing nanoparticle coated hydrophobic fluorocarbon backbone depicting amorphous glassy matrix comprising (a) pristine inert polymer, (b) matrix after nanoparticle spray coating, and (c) ionomer attachment after annealing.

[0662] FIG. 107. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, PFSA-PTFE ionomeric membrane, pillar link bridging membrane to endoskeleton, pores created by sacrificial fillers, and nanocoating.

[0663] FIG. 108. Modified fluorocarbon backbone contrasting m repeated chains of PFMMD and PDD.

[0664] FIG. 109. Process flow for amorphous glassy matrix membrane formation including starting materials PDD.sub.m and PSVE, polymerization, and subsequent hydrolysis.

[0665] FIG. 110. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, sulfonated fluorocarbon glass (SFG) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0666] FIG. 111. Process flow for converting styrene monomers into a polymer.

[0667] FIG. 112. Process flow for fabricating a polymer membrane by grafting a bromated hydrocarbon onto a polyolefin polyethylene backbone.

[0668] FIG. 113. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, sulfonated or bromated polyethylene (SPE, BrPE) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0669] FIG. 114. Process flow for synthesis of a polymer membrane based on combining phosphorylated polyvinyl alcohol (PVA), phosphorylated cellulose acetate (CA), and glutaraldehyde (GA) to form the polymeric ionomer PVA-CA.

[0670] FIG. 115. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, functionalized polyvinyl alcohol ionomeric membrane (CA-PVA, SPVA), pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Ionomer may comprise cellulose acetate (CA) or sulfonic acid (not shown).

[0671] FIG. 116. Process flow for synthesis of a polymer membrane based on sulfosuccinic acid (SSA) treated polyvinyl alcohol (PVA) to form the polymeric ionomer PVA-SSA.

[0672] FIG. 117. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, cross-linked sulfonated polyvinyl alcohol (sPVA) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. As shown, sulfonic acid acts as SSA co-polymer cross linker.

[0673] FIG. 118. Process flow for synthesis of a polymer membrane based on combining polyvinylidene fluoride (PVDF), polyvinyl pyrrolidone (PVP), and polystyrene sulfonic acid (PSSA) to form the polymeric ionomer PVDF-PVP-PSSA.

[0674] FIG. 119. Exemplary polymers able to bond with polyvinylidene fluoride (PVDF) in forming ionomeric polymers comprising polyvinyl alcohol (PVA), poly (methyl methacrylate) (PMMA), polycarbonate (PC), and perfluorosulfonic acid (PFSA), or combinations thereof.

[0675] FIG. 120. Process flow for synthesis of a polymer membrane based on combining polyvinylidene fluoride (PVDF), polyvinyl pyrrolidone (PVP), and sulfamic acid (SA) to form the polymeric ionomer PVDF-PVP-SA.

[0676] FIG. 121. Process flow for synthesis of a polymer membrane by converting polyvinylidene fluoride (PVDF) into dehydrofluorinated polyvinylidene fluoride (D-PVDF) then combined with 3-sulfopropyl acrylate (SPA) and azobisisobutyronitrile (AIBN) to form PVDF-AIBN-SPA.

[0677] FIG. 122. Process flow for synthesis of a polymer membrane by combining dehydrofluorinated polyvinylidene fluoride (D-PVDF) with 1H, 1H, 2H-perfluoro-1-hexene (PFH), 3-sulfopropyl acrylate (SPA), and azobisisobutyronitrile (AIBN) to form PVDF-AIBN-SPA-PFH.

[0678] FIG. 123. Process flow for synthesis of a polymer membrane by combining polyvinylidene fluoride (PVDF) and hexafluoropropylene (HFP) with diisopropyl peroxidicarbonate (DIPPDC) and 1,1,2-trichlorotrifluoroethane (R-113) to produce polymer PVDF-HFP subsequently sulfonated by treatment in CI-SO.sub.3H and HCl.

[0679] FIG. 124. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, sulfonated polyvinylidene fluoride (PVDF) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. PVDF may comprise a variety of polymer isomers, copolymers, and variants including PVP-PSSA, PMMA, PC, PFSA. PVP-SA, AIBN-SA, AIBN-SPA, AIBN-SPA-PFH, and/or HFP.

[0680] FIG. 125. Composition of a membrane comprising a copolymer blend of the polyolefin polypropylene and perfluorosulfonic acid.

[0681] FIG. 126. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, copolymer blend of polypropylene (PP) and perfluorosulfonic acid (PFSA) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0682] FIG. 127. Process flow for synthesis of a polymer membrane by combining polyvinyl chloride (PVC) and ethylenediamine (EDA), then treating the polymer with sulfuric acid H.sub.2SO.sub.4 to produce sulfonated PVC.

[0683] FIG. 128. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, sulfonated polyvinyl chloride (sPVC) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0684] FIG. 129. Process flow for synthesis of a heterogenous polymer membrane by combining 2,2-bis[4-(4-aminophenoxy) phenyl] propane (BAPP) with 4,4-diaminodiphenyl ether-2,2-disulfonic acid (ODADS) and 4,4-bisphenol A dianhydride (BPADA) to produce sulfonated polyamide (sPI).

[0685] FIG. 130. Process flow for synthesis of a heterogenous polymer membrane by combining an aromatic sulfonamide such as sulfonated 1,4-bis(4-aminophenoxy)benzene (pBABTS) with diamine and dianhydride to produce sulfonated polyamide (PI).

[0686] FIG. 131. Exemplary molecules for polyimide based polymer membrane synthesis including sulfonamides, diamines, and dianhydrides.

[0687] FIG. 132. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, sulfonated polyimide (sPI) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0688] FIG. 133A. Comparison of homopolymer, linear copolymer, and angled linear copolymer molecules.

[0689] FIG. 133B. Comparison of cross-linked polymers with copolymer and ligand links.

[0690] FIG. 133C. Comparison of cross-link loop and ionomer-link loop homopolymers, and ionomer-link multi-chain copolymers

[0691] FIG. 134. Process flow for fabricating sulfonated heteropolymer polystyrene involving (a) conventional method, (b) high mole-fraction sulfonic acid synthesis.

[0692] FIG. 135A. Process flow for fabricating sulfonated heteropolymer polystyrene involving (a) n-butyl styrenesulfonate monomer, (b) styrenesulfonate sSA homopolymer.

[0693] FIG. 135B. Process flow for fabricating sulfonated heteropolymer polystyrene involving (c) cross linking of styrenesulfonate CL-sSA polymer.

[0694] FIG. 136. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, sulfonated polystyrene (sPS) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0695] FIG. 137. Chemical structure of heteropolymer polymer comprising sulfonated poly (fluorenyl ether ketone nitrile).

[0696] FIG. 138. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, sulfonated poly (fluorenyl ether ketone nitrile) ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0697] FIG. 139. Chemical structures of heteropolymer polymer precursors including poly(p-phenylene 2,5-disulfonic acid) (PPDSA), poly(p-biphenylene 3,3-disulfonic acid) (PBPDSA), sulfonated sidechain polyphenylene (sPP), and poly[(p-biphenylene 3,3-disulfonic acid)-co-(p-phenylene 2,5-disulfonic acid)](BXPY).

[0698] FIG. 140. Process flow for fabricating sulfonated polyphenylene heteropolymers comprising (a) poly(benzoyl-1,4-phenylene, and (b) poly(p-phenoxybenzoyl-1,4-phenylene).

[0699] FIG. 141. Process flow for fabricating sulfonated polyphenylene heteropolymer SPP-QP comprising SP and QP monomers.

[0700] FIG. 142. Sulfophenylated polyphenylene (sPPP) comprising a generic heteropolymer comprising radicals sPPP-H.sup.+, sPPN-H.sup.+, and sPPB-H.sup.+.

[0701] FIG. 143. Sulfophenylated polyphenylene (sPPP) heteropolymer radicals sPPT-H.sup.+ and sPPBm-H.sup.+.

[0702] FIG. 144. Sulfophenylated polyphenylene (sPPP) heteropolymer radicals sPPP N-free, sPPP (1+0)N, sPPP (1+1)N, sPPP (3+0)N, and sPPP (3+3)N.

[0703] FIG. 145. Chemical structures of heteropolymer sulfophenylated polyphenylene containing sterically hindered pyridines.

[0704] FIG. 146. Process flow to modify phenylated polyphenylene (PPP) heteropolymer into sulfonated Diels-Alder polyphenylene SDAPP.

[0705] FIG. 147. Process flow for synthesis of a sulfonated phenylated polyphenylene sPPP-H.sup.+ from a pre-functionalized diene monomer tetra(para-sulfonated) triethylammonium bistetracyclone salt (TEAsBTC).

[0706] FIG. 148. Process flow for synthesis for hydroxylation of sulfonated phenylated polyphenylene sPPP-H.sup.+ into hydroxylated sulfonated phenylated polyphenylene sPPP-OH.

[0707] FIG. 149. Processes for (a) diazotization of 4,4-diamino-2,2-biphenyldisulfonic acid (DiBPS) into 4,4-diiodo-2,2-biphenyldisulfonic acid (DilPS), and (b) halogenation of 4,4dibromobiphenyl (DBrPh) into 4,4dibromo-3,3biphenyldisulfonic acid (DiBrBS).

[0708] FIG. 150. Variations in radical R group for (a) 4,4-diiodo-2,2-biphenyldisulfonic acid (DilPS) and (b) 4,4dibromo-3,3biphenyldisulfonic acid (DiBrBS).

[0709] FIG. 151. Exemplary variations in sulfonated polyphenylene sidechains.

[0710] FIG. 152. Process for synthesis of sulfonimide branched poly(phenylenebenzophenone)s (Si-branched PPBP) polymers.

[0711] FIG. 153. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, sulfonated polyphenylene branched ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. The sulfonated polyphenylene (sPP) family of polymers may comprise an ionomer of reactive sulfonic acid groups SO.sub.3H including variants sP, sPP, PPDSA, sPP-QP, sPPP-H.sup.+, sPPN-H.sup.+, sPPB-H.sup.+, sPPT-H.sup.+, sPPBm-H.sup.+, sPPBo-H.sup.+, sPPP-OH, sPPP N-free, sPPP (X+0)N, sPPP (X+1)N, BXPY, sPPP, DiBPS, DiPS, DiBrBS, and Si-PPBP.

[0712] FIG. 154. Process flow for synthesis of the heteropolymer polyarylene ether (SPAE) from 4,4-(9-fluorenylidene) diphenol (BPFL), decafluorobiphenyl (DFBP), 4,4(hexafluoroisopropylidene) diphenol (BPHF).

[0713] FIG. 155. Process flow for synthesis of the heteropolymer sulfonated polyarylene ether (SPAES) from 4,40-difluorodiphenyl (DFDPS); 4,4-dihydroxybiphenyl (BP); and 3,30-Disulfonated-4,40-difluorodiphenyl sulfone (SDFDPS).

[0714] FIG. 156 Process flow for synthesis of the heteropolymer sulfonated polyarylene ether (SPAES) perfluoropolyether grafted graphene oxide (PFPE-GO) from graphene oxide (GO) and fluorinated surfactant Krytox 157 FSL.

[0715] FIG. 157. Chemical structural depiction of exemplary heteropolymer sulfonated polyarylene ether (SPAE) incorporating phosphotungstic acid (PWA) and graphene oxide (GO).

[0716] FIG. 158. Molecular structure exemplary heteropolymer polyarylene ether sulfone (SPAEA) including sulfonated radical ionomer variants.

[0717] FIG. 159. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, polyarylene ether (SPAE) including sulfonated radical variants ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Polymer may embed perfluoropolyether grafted graphene oxide (PFPE-GO) as permanent filler.

[0718] FIG. 160. Process flow forming an unfunctionalized polymer poly ether-ether ketone (PEEK).

[0719] FIG. 161. Exemplary process to functionalize insulative poly ether-ether ketone (PEEK) into ionomeric polymer sulfonated poly ether-ether ketone (sPEK).

[0720] FIG. 162. Examples of various functionalized ether ketone polymers, specifically sulfonated poly ether ketone (sPEK), sulfonated poly ether-ether ketone (sPEEK), and sulfonated poly ether ketone-ketone (sPEKK).

[0721] FIG. 163. Further examples of various functionalized ether ketone polymers, specifically sulfonated poly ether-ether-ether ketone (sPEEEK), sulfonated poly ether-ether ketone-ketone (sPEEKK), sulfonated poly ether ketone-ketone-ketone (sPEKKK).

[0722] FIG. 164. A further example of a functionalized ether ketone polymer, specifically sulfonated poly ether ketone ether ketone-ketone (sPEKEKK).

[0723] FIG. 165. An exemplary process to synthesize a functionalized ionomeric polymer comprising sulfonated poly ether ketone (sPEK).

[0724] FIG. 166. An exemplary process to synthesize a linear copolymer of sulfonated poly ether ketone bonded to a non-functionalized poly ether ketone chain (sPEK-co-PEK, aka 2PEK).

[0725] FIG. 167. An exemplary process to synthesize a functionalized ionomeric polymer comprising sulfonated poly ether-ether ketone (sPEEK).

[0726] FIG. 168. An alternative process to synthesize a functionalized ionomeric polymer comprising sulfonated poly ether-ether ketone (sPEEK).

[0727] FIG. 169. Another process to synthesize a functionalized ionomeric polymer comprising sulfonated poly ether-ether ketone (sPEEK).

[0728] FIG. 170. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, a poly ether ketone (PEK) and poly ether-ether ketone (PEEK) based polymers and variants thereof including sulfonated functional groups, ionomeric membranes, pillar links bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0729] FIG. 171. An exemplary process to synthesize an insulative polymer comprising poly ether-ether sulfone (PEESf).

[0730] FIG. 172. Exemplary process to functionalize insulative poly ether-ether sulfone (PEESf) into ionomeric polymer sulfonated poly ether-ether sulfone (sPEESf).

[0731] FIG. 173. An exemplary process to synthesize an ionomeric polymer comprising sulfonated poly ether sulfone (sPESf).

[0732] FIG. 174. Exemplary copolymer of sulfonated poly ether-ether sulfone (sPEES) cross linked via sulfonic acid to poly(ether imide) (PEI) chain.

[0733] FIG. 175A. Exemplary processes to synthesize poly ether sulfones by self-polycondensation of monomers.

[0734] FIG. 175B. Exemplary processes for sulfonating polyether sulfones.

[0735] FIGS. 176A-176B. An exemplary process for converting sulfonated poly ether-ether sulfone (sPEES) into sulfonated poly(1,4-phenylene ether-ether-sulfone)-poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (sP(PhEESf)-PAMPS).

[0736] FIG. 177A An exemplary process to synthesize an insulating polymer comprising bis-hydroxyphenyl ether sulfone (BH-PEDSf) functionalized into sulfonated polyether di-sulfone (sPEDSf).

[0737] FIG. 177B. An exemplary process to synthesize an insulating polymer comprising bis-hydroxyphenyl ether sulfone (BH-PEDSf) functionalized into sulfonated polyether di-sulfone (sPEDSf).

[0738] FIG. 178. An exemplary process to synthesize an ionomeric polymer comprising sulfonated fluorinated polyethersulfone (sFPESf).

[0739] FIG. 179. Exemplary process for synthesizing sulfonated poly(ether sulfone) sP(PhESf) from a hydroxy-quaterphenol aromatic diol containing four phenyl substituents at the 2, 2, 6, and 6 positions of 4,4-diphenyl ether.

[0740] FIG. 180. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton, a poly ether sulfone (PEES) based polymer and variants thereof including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Variants include ionomer cross linked copolymers comprising SPEES and poly(ether imide) (PEI).

[0741] FIG. 181A. An exemplary process to synthesize an insulative polymer comprising poly ketone-ketone sulfone (PKKSf) functionalized into sulfonated polyketone ketone sulfone (sPKKSf).

[0742] FIG. 181B. An exemplary process to synthesize an insulative polymer comprising poly ketone-ketone sulfone (PKKSf) functionalized into sulfonated polyketone ketone sulfone (sPKKSf).

[0743] FIG. 182A. An exemplary process to synthesize an insulating polymer comprising poly (arylene ketone ether ketone sulfone) (PAKEKSf) as a precursor to its sulfonated derivative sulfonated poly (arylene ketone ether ketone sulfone) sPAKEKSf.

[0744] FIG. 182B. An exemplary process to synthesize an insulating polymer comprising poly (arylene ketone ether ketone sulfone) (PAKEKSf) as a precursor to its sulfonated derivative sulfonated poly (arylene ketone ether ketone sulfone) sPAKEKSf.

[0745] FIG. 183A. An exemplary process to synthesize an ionomeric polymer comprising sulfonated di-poly (arylene ketone ether sulfone) (s2PAKESf).

[0746] FIG. 183B. An exemplary process to synthesize an ionomeric polymer comprising sulfonated di-poly (arylene ketone ether sulfone) (s2PAKESf).

[0747] FIG. 184. Exemplary process to synthesize sulfonated poly (arylene ether ketone sulfone) (sPAEKSf) from phenyl, benzene, ether, and sulfone compounds.

[0748] FIG. 185A. Exemplary processes to synthesize bismuth trimesic acid (BiTMA) and bismuth molybdate (Bi.sub.2MoO.sub.6) as conductive and catalytic fillers for ion exchange membranes.

[0749] FIG. 185B. Exemplary process for functionalizing sulfonated poly ether sulfone (sPESf) to form heteropolymers comprising sulfonated poly(ether sulfone)-(bismuth trimesic acid) (sPESf-BiTMA) and poly(sulfonated ether sulfone)-(bismuth molybdate) (SPESf-Bi.sub.2MoO.sub.6).

[0750] FIG. 186. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; poly ketone sulfone (PKS), poly ether sulfone (PES), and poly ketone-ether sulfones (PKES) based polymers and variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Permanent fillers include bismuth trimesic acid (SPES-BiTMA) and bismuth molybdate (SPES-Bi.sub.2MoO.sub.6).

[0751] FIG. 187. Structural representations of single-wall and multi-wall carbon nanotubes (SW and MW CNTs) FIG. 188. Exemplary process for functionalization of carbon nanotubes using sonication.

[0752] FIG. 189. Exemplary process for functionalization of carbon nanotubes by grafting of carboxylic acid salt.

[0753] FIG. 190. Illustrative process for synthesis of proton exchange membranes comprising various polymers including PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI and CS; doped with catalyst and ionomer functionalized carbon nanotubes including SO.sub.3H, COOH, POH, NH.sub.2, SiO.sub.2, and TiO.sub.2.

[0754] FIG. 191. Exemplary process for forming perfluoropolyether grafted graphene oxide (PFPE-GO).

[0755] FIG. 192. Exemplary process for grafting poly (2,5-benzimidazole) onto graphene oxide to form ABPBI-GO.

[0756] FIG. 193. Structure of poly (3,4-benzimidazole) grafted onto graphene oxide to form ABPBI-GO.

[0757] FIG. 194. Various graphene oxide structures comprising Hofmann, Ruess, Scholz-Boehn, and Lerf-Klinowski topographies.

[0758] FIG. 195. Schematic representation of methanol membrane cross-over with and without carbon nano-flake interfacial coating.

[0759] FIG. 196. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymers and variants thereof comprising (without limitation) PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI and CS; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Permanent fillers include functionalized graphene oxides including PFPE-GO, ABPBI-GO and topographical variation thereof; along with carbon nanotubes functionalized by SO.sub.3H, COOH, POH, NH.sub.2, SiO.sub.2, or TiO.sub.2.

[0760] FIG. 197. Schematic representation of silicates categorized as amorphous silicon dioxide, tetrahedral nesosilicates, and mesostructured silica cellular foam including semi-hollow spheroids.

[0761] FIG. 198. Exemplary process for synthesizing phosphorylated hollow mesoporous silica phosphoric acid (HMS-PA) nanospheres from silica mesostructured cellular foam.

[0762] FIG. 199. Exemplary process for synthesizing functionalized nanospheres comprising silica mesostructured cellular foam with sulfonic acid termini (MCF-SO.sub.3H).

[0763] FIG. 200. Schematic representation of protonic polymer conduction via charge hopping between ionomeric polymer and sulfonated mesostructured cellular foam nanospheres.

[0764] FIG. 201. Schematic representation of polymer conduction via vehicular transport of protons via hydronium ion electric drift and/or diffusion.

[0765] FIG. 202. Exemplary processes for doping a polymer such as sPEES with amino-functionalized and sulfonated mesostructured cellular foam nanospheres to form filler doped membranes sPEES-MCF-NH.sub.2 and sPEES-MCF-HSO.sub.3 respectively.

[0766] FIG. 203. Exemplary process for self assembly of aluminum-substituted mesoporous silica as a MCF-ionomer.

[0767] FIG. 204. Exemplary process for the synthesis of a poly(m-phenylene)-bibenzimidazole) membrane doped with aluminum-grafted mesoporous silica cellular foam filler (mPBI-MCF).

[0768] FIG. 205. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymers and variants thereof comprising (without limitation) PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI and CS; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Permanent fillers include phosphoric acid doped hollow mesoporous silica (HMS-PA), mesostructured cellular foam (MCF-SO.sub.3H, hydroxy MCF, MCF-NH.sub.2), and/or mesoporous silica Al-grafted MCF ionomer.

[0769] FIG. 206A. Exemplary process for the synthesis of perfluoro-methylene-methyl-dioxolane monomers (PFMMD/PFMDD monomers).

[0770] FIG. 206B. Exemplary process for the synthesis of a perfluoro-2-hydro-2,4-dimethyl-1,3-dioxolanes (PFMMD/PFMDD polymerizers).

[0771] FIG. 206C. Exemplary process for the synthesis of perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD/PFMDD polymers).

[0772] FIG. 206D. Structural variants of perfluoro (methylene-r) dioxolane moieties PF(M.sub.r)D including PFMD, PFMMD, and PDMDD.

[0773] FIG. 207. Process flow for synthesizing PFMMD and PFMDD copolymers with PFMD and CTFE.

[0774] FIG. 208. Process flow for synthesizing a copolymer of PFMMD and PFSt.

[0775] FIG. 209A. Chemical structure comparison of perfluoro-2-methylene-4-methyl-1,3-dioxolane-perfluorosulfonic acid (PFMMD-PFSA) linear copolymer to conventional PFSA-PTFE composite polymers.

[0776] FIG. 209B. Cross sectional comparison of perfluoro-2-methylene-4-methyl-1,3-dioxolane-perfluorosulfonic acid (PFMMD-PFSA) linear copolymer to conventional PFSA-PTFE composite polymers.

[0777] FIG. 210. Exemplary process for fabricating a linear fluorinated methylated copolymer PFMMD-co-PFSA comprising perfluoro-2-methylene-4-methyl-1,3-dioxolane and perfluorosulfonic acid.

[0778] FIG. 211A. Structural chemical representation of a linear tri-copolymer of perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD) with perfluoro-2-methylene-1,3-dioxolane (PFMD) and perfluorosulfonic acid (PFSA).

[0779] FIG. 211B. Structural chemical representation of a linear tri-copolymer of perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PFMDD) with perfluoro-2-methylene-1,3-dioxolane (PFMD) and perfluorosulfonic acid (PFSA).

[0780] FIG. 211C. Structural chemical representation of a linear tri-copolymer of perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD) with chlorotrifluoroethylene (CTFE) and perfluorosulfonic acid (PFSA).

[0781] FIG. 211D. Structural chemical representation of a linear tri-copolymer of perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PFMDD) with chlorotrifluoroethylene (CTFE) and perfluoro-sulfonic acid (PFSA).

[0782] FIG. 211E. Structural chemical representation of a linear tri-copolymer of perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD) with pentafluorostyrene (PFSt) and perfluorosulfonic acid (PFSA).

[0783] FIG. 211F. Structural chemical representation of a linear tri-copolymer of perfluoro-2-methylene-17 4,5-dimethyl-1,3-dioxolane (PFMDD) with (PFSt) and perfluorosulfonic acid (PFSA).

[0784] FIG. 212. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; copolymers of perfluoro-2-methylene-4-methyl-1,3-dioxolane and perfluorosulfonic acid (PFMMD-co-PFSA) and numerous variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0785] FIG. 213. Exemplary process for fabricating poly(2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carbonyl) sulfanoyl fluoride-co-styrene (PDDP-CSFS).

[0786] FIG. 214. Exemplary process for converting 4-(phenylsulfonyl)-1,1-biphenyl (Pmax-1200) into sulfonated 4-(phenylsulfonyl)-1,1-biphenyl (SPmax-1200).

[0787] FIG. 215A. Exemplary process for fabricating a hybrid copolymer of poly(2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carbonyl) sulfanoyl fluoride-co-styrene and high X sulfonated 4-(phenylsulfonyl)-1,1-biphenyl (PDDP-CSFS-co-SPmax-1200).

[0788] FIG. 215B. Chemical representation of copolymer PDDP-CSFS-co-SPmax.

[0789] FIG. 216. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; copolymers of poly (2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carbonyl) sulfanoyl fluoride-co-styrene with high sulfonated 4-(phenylsulfonyl)-1,1-biphenyl (PDDP-CSFS-co-SPmax-1200) and variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0790] FIG. 217. Exemplary process for fabricating of phenyl-alkane copolymer, steps 1 monomer and 2 polymerization.

[0791] FIG. 218. Exemplary process for fabricating of phenyl-alkane copolymer, step 3 sulfonation.

[0792] FIG. 219. Exemplary process for fabricating of phenyl-alkane copolymer, step 4, cross linking.

[0793] FIG. 220. Alternative process for fabricating of phenyl-alkane copolymer.

[0794] FIG. 221. Exemplary process for fabricating of phenyl-aldehyde.

[0795] FIG. 222. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; sulfonated phenyl-co-alkane (sPh-C.sub.nH.sub.2n+2) and sulfonated phenyl-co-aldehyde (sPh-CHO) copolymers and variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0796] FIG. 223. Exemplary chemical formulation of linear and cross-linked poly(trifluorostyrene) PTFS and PTFS-X.

[0797] FIG. 224. Exemplary chemical formulation of copolymer of polystyrene and polystyrene-sulfonate (PS-co-sPSS).

[0798] FIG. 225. Exemplary chemical formulation of polystyrene sulfonic acid (PSSA) grafted onto perfluoroalkoxy alkane (PFA) polymer.

[0799] FIG. 226A. Chemical structure of copolymer of thermoplastic polyurethane and sulfonated divinyl benzene (PTPU-co-sDVB).

[0800] FIG. 226B. Chemical structure of tri-copolymer comprising thermoplastic urethane (TPU) crosslinked to polystyrene sulfonate (PSS) through sulfonated divinyl benzene (sDVB).

[0801] FIG. 227. Schematic representation of linear block copolymer of flexible polyurethane (PTU ester) and semi-rigid PTU backbone cross linked to polystyrene sulfonate (PSS) via sulfonated divinyl benzene (sDVB).

[0802] FIG. 228. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; with polymers comprising linear and cross-linked sulfonated poly(trifluorostyrene) (sPTFS/sPTFS-X), polystyrene-co-polystyrene-sulfonate copolymers (PS-co-sPSS), polystyrene sulfonic acid grafted onto perfluoroalkoxy alkane (PFA-g-PSSA), and styrene-urethane copolymer comprising thermoplastic polyurethane bonded to divinyl benzene vias polystyrene sulfonate with variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0803] FIG. 229. Exemplary representation of a polysulfone (PSU, PSf) molecule.

[0804] FIG. 230. Exemplary process for synthesizing a sulfonated polysulfone (sPSU, sPSf) polymer.

[0805] FIG. 231. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; sulfonated polysulfone (sPSU, sPSf) polymer and variants thereof; sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0806] FIG. 232. Exemplary process for synthesizing sulfonimide with a benzoic acid radical.

[0807] FIG. 233A. Exemplary process for copolymerization of sulfonated polyamide (SPA) and sulfonimide (Slm) to form poly (sulfonated polyamide sulfonimide).

[0808] FIG. 233B. Exemplary process for copolymerization of functionalized sulfonated polyamide (sSPA) and sulfonimide (Slm) to form functionalized copolymer sSPA-co-Slm.

[0809] FIG. 234. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; sulfonated polyamide sulfonimide linear copolymer and variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0810] FIG. 235A. Exemplary process for synthesizing poly-sulfonated phosphazene P(sPz) from a phosphazene P(Pz) monomer.

[0811] FIG. 235B. Heteropolymer comprising poly-sulfonated phosphazene P(sPz) and un-sulfonated phosphazene P(Pz).

[0812] FIG. 236. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; sulfonated phosphazene polymer and variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0813] FIG. 237. Chemical representation of poly sulfonated siloxane P(SSiX).

[0814] FIG. 238. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; sulfonated siloxane polymer and variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0815] FIG. 239. Chemical representations of various triazine moieties.

[0816] FIG. 240. Exemplary process for synthesizing a covalent triazine framework comprising triazine.

[0817] FIG. 241. Exemplary processes for synthesizing various topologies of covalent triazine frameworks including a twelve-element s6T6Ph sCTF-12 comprising six triazine groups and six sulfonated phenols, a s3T6Ph sCTF-9 with a nine element ring comprising three triazine groups and six sulfonated phenols, and a twelve-element 6T6Ph-F.sub.4 CTF-12 comprising six triazine groups and six F.sub.4 fluorinated phenol rings.

[0818] FIG. 242. Chemical representations of three different phosphoric acid (H.sub.3PO.sub.4) functionalized covalent triazine frameworks (CTF) comprising phenylated triazine (CTF-Ph), tris(4-formylphenyl)amine (CTF-TPA), and triazine trifluoride (CTF-TF).

[0819] FIG. 243A. Chemical representation of a twenty-four element (6T12Ph6bPy)-configured sTCF-24 sulfonated covalent triazine framework comprising 6 triazine, 12 phenols, and 6 bi-pyrroles.

[0820] FIG. 243B. Exemplary process for copolymerizing covalent triazine framework (CTF) with polyvinylidene fluoride (PVDF) to form covalent triazine framework polyvinylidene fluoride copolymer CTG-co-PVDF.

[0821] FIG. 243C. Chemical representation of a twenty-four element 6Y18Ph configured sCTF-24 sulfonated covalent triazine framework comprising 6 triazine and 18 sulfonated phenol groups with intercalated Pd catalyst.

[0822] FIG. 244. Exemplary process for doping a triazine substrate with phosphoric acid (H.sub.3PO.sub.4).

[0823] FIG. 245. Chemical representation of sulfonated poly(arylene ether sulfone) triazine bisphenol linear copolymer P(SPAES)-co-TBPh comprising triazine-containing bisphenols and functional group (BPhSf).

[0824] FIG. 246. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; covalent triazine framework polyvinylidene fluoride copolymer (CTF-co-PVDF), phosphoric-doped triazine substrate, and variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0825] FIG. 247A. Exemplary process for synthesizing sBVlm-TfO-co-MMA sulfobutyl-vinylimidazolium-trifluoro methane sulfonate-co-methyl methacrylate.

[0826] FIG. 247B. Exemplary process for polymerizing methyl methacrylate (MMA) monomer into non-functionalized electrical insulating poly(methyl methacrylate) (PMMA).

[0827] FIG. 248. Chemical representation of various methacrylate monomers including methacrylate (MA), methacrylate acid (MAA), methyl methacrylate (MMA), butyl methacrylate (BMA), and hydroxyethyl methacrylate (HEMA).

[0828] FIG. 249. Exemplary processes for synthesizing poly(methyl methacrylate) nanospheres (PMMA-NS).

[0829] FIG. 250. Exemplary process for converting methyl methacrylate-ran-methacrylic acid (MMA-MAA) into Pd-poly(methyl methacrylate) nanospheres (Pd PMMA NS).

[0830] FIG. 251. Chemical representation of carboxylate Pd bridging of methyl methacrylate-ran-methacrylic acid chain (Pd-MMA-MAA) including symmetrical, asymmetrical, coordinated and non-coordinated bridges.

[0831] FIG. 252. Exemplary process for reducing Pd.sup.2+ ions into Pd.sup.0 nanoclusters using a benzene-methanol solution of Pd(CH.sub.3COO).sub.2-poly(methyl methacrylate-ran-methacrylic acid) (MMA-MAA).

[0832] FIG. 253. Exemplary process for synthesizing PPMA nanospheres, then functionalizing and sulfonating the nanosphere surface with SO.sub.3H.

[0833] FIG. 254. Generalized process for converting functionalized PMMA nanospheres into ionomer coated nanospheres.

[0834] FIG. 255. Exemplary process for synthesizing PPMA nanospheres then converting them into porous nanospheres.

[0835] FIG. 256A. Exemplary process for synthesizing poly methyl methacrylate zinc nanoclusters (PMMA Zn NCs) then sulfonating the zinc to form poly methyl methacrylate with sulfonated zinc nanoclusters (PMMA sZn NCs).

[0836] FIG. 256B. Inventive process to convert poly methyl methacrylate zinc nanospheres or nanoclusters (PMMA Zn.sup.2+ NS/NC) into zinc-oxide functionalized PMMA nanospheres or nanoclusters (PMMA ZnO NS/NC).

[0837] FIG. 257. Chemical representation of poly methyl methacrylate (PMMA) isometries including isotactic, syndiotactic, and atactic configurations.

[0838] FIG. 258. Exemplary process for grafting poly(methyl methacrylate) onto polyester to form grafted polymer PE-g-PMMA.

[0839] FIG. 259. Comparison of chemical representations for various polymers of poly(methyl methacrylate) including linear copolymers of PMMA with maleic anhydride (MAH) and with maleic anhydride derivative (MI) to form poly(MMA-co-MAH) and poly(MMA-co-MAF-co-MI).

[0840] FIG. 260. Exemplary process for grafting methyl methacrylate MMA onto a polyvinylidene fluoride polymeric chain PCDF to form the copolymer PVDC-g-MMA.

[0841] FIG. 261. Exemplary process for forming a liner copolymer of maleic anhydride MA and methyl methacrylate (MMA) to synthesize PMMA-co-MAH.

[0842] FIG. 262. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymeric membranes comprising pure poly methyl methacrylate (PMMA), copolymers of PMMA with maleic anhydride (PMMA-co-MAH), copolymers of PMMA with maleic anhydride derivative (PMMA-co-MAH-co-Mi), grafted polymers of PMMA and polyvinylidene fluoride PMMA-g-PVDC and variants thereof; including sulfonated functional groups, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. PPMA polymers may be functionalized by ZnS PMMA nanoclusters, PMMA nanospheres and porous nanosphere either attached to polymeric chains or bridging multiple chains. The ZnS PMMA nanoclusters and PMMA nanospheres may also be used as permanent ionomeric fillers for other polymer films such as those comprising PFSA, PFSA-PTFE, SPAES, SPEEK, PBI and CS mainchains.

[0843] FIG. 263. Matrix representation of a hybrid copolymer comprising sulfonated poly (vinyl alcohol) with carboxy methyl cellulose and acrylamide containing carboxylated carbon nanotubes (CCNT) and sulfonated activated carbon (SAC) filler for conduction and cross linking of chains. CNTs may be functionalized by various ionomeric groups such as COOH, OH, or SO.sub.3H groups or by introducing SO.sub.3H groups using polystyrene sulfuric acid. Activated carbon fillers may be functionalized by SO.sub.3H. Poly vinyl alcohol may include zinc oxide nanoparticles (not shown) cross-linking the PVA matrix.

[0844] FIG. 264. Chemical representation of a PFSA-like fluorocarbon mainchain comprising a multi-acid sidechain (MASC) as a pendant securing an ionomer group such as perfluoro imide acid (PFIA) to the polymeric mainchain. Examples of MASCs comprise pendants containing sulfonyl (OSO), thiol (SH), hydrazine (HN), and difluoromethylene (CF.sub.2).

[0845] FIG. 265A. Exemplary processes for forming varying length multi-acid sidechains (MASCs) with an ionomeric terminus comprising sulfonylhydrazide (SO.sub.2HNSO.sub.2). Please note that although at first glance the pendants shown on the left right side flow charts may appear identical there are subtle differences in the chain lengths that can affect crystallinity and fuel crossover especially in direct methanol fuel cells (DMFC).

[0846] FIG. 265B. Process sequence for converting PFSA into a multi-acid sidechain (MASC) comprising perfluoro bis(sulfonyl) imide-acid (PFIA).

[0847] FIG. 265C. Process sequence for converting PFSA into a multi-acid sidechain (MASC) comprising 2-sulfobenzene bissulfonylimide (ortho-bis acid).

[0848] FIG. 266. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising fluorocarbon and hydrocarbon polymers such as PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI and CS and variants thereof but including multi acid sidechains containing sulfonyl (OSO), thiol (SH), hydrazine (HN), and difluoromethylene (CF.sub.2); and with ionomeric termini including sulfonated functional groups such sulfonic acid or sulfonylhydrazide, ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0849] FIG. 267. Exemplary processes for forming sulfonated arylene-ether hybrid polymer sP.sub.12F.sub.97B.

[0850] FIG. 268. Exemplary processes for forming sulfonated arylene-ether hybrid polymer sP6F9CB.

[0851] FIG. 269. Chemical representation of sulfonated arylene-ether hybrid polymer identifying constituent groups including fluorinated polymer 12F, sulfonated polymers 7BF and CB, and fluorinated sulfonated polymer 6F.

[0852] FIG. 270. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising sulfonated poly(arylene ether) such as sP12F97B and sP6F9CB and variants thereof; including a sulfonated ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers.

[0853] FIG. 271. Quasi-3D chemical representation of thiol polyhedral oligomeric silsesquioxanes (POSS-SH).

[0854] FIG. 272. Exemplary processes for synthesis of phosphoric polyhedral oligomeric silsesquioxanes comprising conversion of 3-mercaptopropyl trimethoxysilane (3-MPTMS) into thiol polyhedral oligomeric silsesquioxanes (POSS-SH) then functionalized by ethylene glycol methacrylate phosphate (EGMP) to produce POSS-S-PA.

[0855] FIG. 273. Quasi-3D representation of phosphoric acid polyhedral oligomeric silsesquioxanes (POSS-S-PA).

[0856] FIG. 274. Quasi-3D representations of various generic polyhedral oligomeric silsesquioxanes including polyhedral oligomeric SSQ with R radical (POSS-R), octagonal prism SSQ with no radicals (POSS), and octagonal prism SSQ with radicals R (POSS-R).

[0857] FIG. 275. Exemplary processes for synthesis of polyethylene glycol polyhedral oligomeric silsesquioxanes (POSS-PEG).

[0858] FIG. 276. Chemical representations of a several variants of polyhedral oligomeric silsesquioxanes comprising isobutyl polyhedral oligomeric SSQ (POSS-iBu), vinyl polyhedral oligomeric SSQ (POSS-Vi), and 1-chlorobutane polyhedral oligomeric SSQ (POSS-8Cl).

[0859] FIG. 277. Chemical representations of a several variants of polyhedral oligomeric silsesquioxanes comprising octakis (dimethylsilyloxy) polyhedral oligomeric SSQ (Ot-POSS), octavinyl polyhedral oligomeric SSQ (OV-POSS), and octaphenyl polyhedral oligomeric SSQ (Ph-POSS).

[0860] FIG. 278. Chemical representations of a several variants of polyhedral oligomeric silsesquioxanes comprising isobutyl-vinyl polyhedral oligomeric SSQ (POSS-iBu-Vi), isobutyl-butylamine polyhedral oligomeric SSQ (POSS-iBu-NH.sub.2), and isobutyl-CI polyhedral oligomeric SSQ (POSS-iBu-CI).

[0861] FIG. 279. Chemical representations of a several variants of polyhedral oligomeric silsesquioxanes comprising isobutyl-hydroxide polyhedral oligomeric SSQ (POSS-iBu-3OH), isobutyl-styryl polyhedral oligomeric SSQ (POSS-iBu-styryl), and isobutyl-polystyrene polyhedral oligomeric SSQ (POSS-iBu-PS).

[0862] FIG. 280. Chemical representations of a several variants of polyhedral oligomeric silsesquioxanes comprising R-styryl polyhedral oligomeric SSQ (POSS-R-styryl), and R-polystyrene polyhedral oligomeric SSQ (POSS-RPS).

[0863] FIG. 281A. Chemical representations of variants of polyhedral oligomeric silsesquioxanes comprising cyclopentyl-polystyrene polyhedral oligomeric SSQ (POSS-Cp-PS), and cyclohexyl-polystyrene polyhedral oligomeric SSQ (POSS-Cy-PS).

[0864] FIG. 281B. Chemical representations of variants of polyhedral oligomeric silsesquioxanes comprising polyhedral oligomeric SSQvariants aminopropylisobutyl (POSS-AmNH.sub.2); mercaptopropyl-isobutyl (POSS-SH); mono(acryloisobutyl) (POSS-A).

[0865] FIG. 282. Chemical representations of a several variants of polyhedral oligomeric silsesquioxanes comprising polyhedral oligomeric SSQ (POSS-AmNH.sub.2), polyhedral oligomeric SSQ (POSS-SH), and polyhedral oligomeric SSQ (POSS-A).

[0866] FIG. 283. Graphical representation of various polyhedral oligomeric silsesquioxanes topographies including unreactive POSS, 1D POSS elements including pendants, caps, and barbells; planar POSS chains and lattices; and 3D POSS dendrites and three-dimensional matrices.

[0867] FIG. 284. Exemplary processes for synthesis of 3,13-dihydrooctaphenyl double decker silsesquioxane (DDSQ) FIG. 285. Graphical representations of various double-decker silsesquioxanes including non-methylated functionalized double-decker silsesquioxane (NMe DDSQ) and methylated functionalized double-decker silsesquioxane (Me DDSQ).

[0868] FIG. 286A. Exemplary functional groups for double-decker silsesquioxanes and resulting SiO.sub.2 bonding comprising vinyl, methylpropyl, methyltrichlorosilane, dichloromethylvinylsilane, and others.

[0869] FIG. 286B. Exemplary functional groups for double-decker silsesquioxanes and resulting SiO.sub.2 bonding comprising allyloxytrimethylsilane, propyl glycidyl ether, and others.

[0870] FIG. 286C. Exemplary functional groups for double-decker silsesquioxanes and resulting SiO.sub.2 bonding comprising 4-bromostyrene, 4-acetoxystyrene, and others.

[0871] FIG. 287. Structural representations of cubic double-decker silsesquioxanes.

[0872] FIG. 288. Exemplary processes for synthesis of functionalized cubic double-decker silsesquioxane.

[0873] FIG. 289. Exemplary process for synthesis of amino functionalized cubic double-decker silsesquioxane.

[0874] FIG. 290. Chemical constituents of POSS nanocomposites comprising a blend of octameric POSS cages, POSS cage resins, and catalysts.

[0875] FIG. 291 Graphical representation of POSS clusters attaching to polymeric backbone of ion exchange membrane (POSS nanostructures not drawn to scale).

[0876] FIG. 292. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; mainchains comprising fluorocarbon and hydrocarbon polymers including such as PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI and CS, and variants thereof; including a sulfonated ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Permanent fillers include polyhedral oligomeric silsesquioxanes (POSS) with chemical and structural variants including POSS-SH, POSS-S-PA, POSS-PEG, POSS-iBu, POSS-Vi, POSS-BCl, Ot-POSS, OV-POSS, Ph-POSS, POSS-iBu-Vi, POSS-iBu-NH.sub.2, POSS-iBu-CI, POSS-iBu-3OH, POS-iBu-styrl, POSS-iBu-PS, POS-R-styrl, POSS-RPS, POSS-Cp-PS, POSS-Cy-PS, POSS-AmNH.sub.2, POSS-SH, and POSS-A; POSS cages comprising pendants, beads, chains, barbells, planar, dendritic and 3D structures, along with double-decker silsesquioxanes including cubic, DDSQ, and Me DDSQ moieties.

[0877] FIG. 293. Graphical representation of polyimide coating nanocoating of PTFE reinforced PFSA ion exchange membrane illustrating interfacial bonding.

[0878] FIG. 294. Graphical representation of polymeric ion exchange membrane with embedded nanocomposites (elements not drawn to scale).

[0879] FIG. 295A. Exemplary process for synthesis of nanocoated polymer chains by converting extended polytetrafluoroethylene (ePTFE) into a dopamine composite membrane (DCM) and subsequently treated by ZrO.sub.2 using a sol-gel process to produce a zirconium composite membrane (ZCM).

[0880] FIG. 295B. Exemplary process for synthesis of nanocoated polymer chains by converting extended polytetrafluoroethylene (ePTFE) into a dopamine composite membrane (DCM) and subsequently treated by PtO.sub.2 using a sol-gel process to produce a platinum composite membrane (PtCM).

[0881] FIG. 296. Exemplary process for synthesis of nanoparticle coated carbon nanotubes involving the steps of polymer wrapping, polyelectrolyte treatment with either polybenzimidazole (PBI) or pyridine polybenzimidazole (PyPBI) and finally nanoparticle attachment.

[0882] FIG. 297A. Exemplary process for electrostatic functionalization of carbon nanotubes with amino groups.

[0883] FIG. 297B. Exemplary process for coordination bonding of platinum or titanium nanoparticles onto NH.sub.2 functionalized CNTs resulting in platinum amino functionalized nanoparticle coated carbon nanotubes (PtNH.sub.2 NP CNT) and titanium amino functionalized nanoparticle coated carbon nanotubes (TiNH.sub.2 NP CNT) respectively.

[0884] FIG. 298. Exemplary process for tin-platinum coating carbon nanotubes.

[0885] FIG. 299. Graphical representation of polymeric ion exchange membrane with embedded functionalized carbon nanotubes (not to scale).

[0886] FIG. 300. Graphical representation of polymeric ion exchange membrane with embedded nanosphere coated carbon nanotubes (not to scale).

[0887] FIG. 301. Chemical representations of a hybrid polymer comprising sulfonated glutaraldehyde (sGA) cross-linked copolymers 4-sulfophthalic acid (SPA) and poly vinyl alcohol (PVA) including PVA bound polyethylene oxide (PEO) and phosphorated titania carbon nanotubes (PO.sub.4TiO.sub.2).

[0888] FIG. 302. Exemplary process for radiation induced defect and methylene grafting of ionomer onto a base polymer.

[0889] FIG. 303. Schematic representation of nanofiber electrospinning process.

[0890] FIG. 304. Schematic representation of hybrid polymer containing a polymeric backbone with embedded sulfonated polystyrene nanofibers (sPS).

[0891] FIG. 305A. Process sequence for DPA doping of PFSA using membrane swelling pore generation.

[0892] FIG. 305B. Exemplary processes for hybrid polymer or nanofiber synthesis from dopamine (DA) or sulfonated dopamine (sDA) into insulating poly(dopamine) (pDA), ionomeric poly (sulfonated dopamine) (pSDA), or ionomeric linear copolymer poly (dopamine-co-sulfonated dopamine) (p(DA-sDA).

[0893] FIG. 305C. Schematic representation of a poly(dopamine-sulfonated dopamine) doped perfluoro sulfonic acid-polytetrafluoroethylene (PFSA-PTFE.Math.P(DA-sDA)).

[0894] FIG. 305D. Process for DPA doping of polymer membrane using inventive sacrificial filler method to form membrane vacancies to contain the dopant.

[0895] FIG. 306A. Exemplary processes for hybrid polymer synthesis of an antibacterial dopamine substrate with silver nanoparticle coating.

[0896] FIG. 306B. Exemplary processes for hybrid polymer synthesis of a dopamine matrix integrating platinum catalyst, sulfonic acid functionalized nanoparticles, and cobalt scavenger coating.

[0897] FIG. 307. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising fluorocarbon and hydrocarbon polymers including such as PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI and CS, and variants thereof; including a sulfonated ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Nano coatings include functionalized polyimide, nanocomposites, and silver nanoparticles. Permanent fillers include functionalized and nanosphere coated carbon nanotubes, poly dopamine composite membranes, zirconium composite membranes, sol-gel matrix fillers comprising titanium and catalysts, and electrospun nanofibers.

[0898] FIG. 308. Schematic representation of intercalant zirconium (iZr).

[0899] FIG. 309. Moieties of intercalant zirconium including a type Zr with OH terminus, type Zr with 2O termini, and A type Zr with X and Y termini where X=F.sup., Cl.sup., Br.sup., OH.sup., HSO.sub.4 and where Y=H.sub.2O, DMSO. As depicted zirconia may occupy multiple parallel planes.

[0900] FIG. 310. Exemplary processes for converting polyethersulfone into polydopamine sodium bicarbonate then reduced into zirconium nanospheres.

[0901] FIG. 311. Representation of effect of ZrO.sub.2 nanosphere on IEM charge conduction.

[0902] FIG. 312. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising fluorocarbon and hydrocarbon polymers including such as PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI and CS, and variants thereof; including a sulfonated ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. As shown, zirconium fillers may include intercalant zirconium and zirconium nanospheres.

[0903] FIG. 313. Graphical representation of various clusters of metal oxide frameworks (MOFs) including metal-to-organic (M2O) ligand and metal-to-metal (M2M) ligands. Examples in include varying coordination numbers and topologies including convex or starburst MOF with CN=6, cluster MOF with CN=6, and three-dimensional concave MOF with CN=3 arranged in a cubic metal matrix.

[0904] FIG. 314. Graphical representation of a three-dimensional cubic metal oxide frameworks (MOFs) comprising a rectangular or square array with CN=6 including metal-to-organic (M2O) ligand and metal-to-metal (M2M) ligands.

[0905] FIG. 315. Graphical representation of a three-dimensional metal organic framework geometries without guest molecule including cubic. trapezoid, double trapezoid, hexagonal drum (not shown), and octangular drum. For clarity, only metal-to-metal (M2M) ligands are shown.

[0906] FIG. 316. Graphical representation of a three-dimensional metal organic framework geometries with guest molecules shown including cubic. trapezoid, double trapezoid, hexagonal drum (not shown), and octangular drum. For clarity, only metal-to-metal (M2M) ligands are shown.

[0907] FIG. 317. Graphical representations of metal oxide frameworks including atomic stack of metals (left), sulfonated double trapezoidal MOF (center), and PFSA-PTFE membrane with embedded MOFs (right).

[0908] FIG. 318. Graphical representation of MOF-to-MOF and MOF-to-polymer bonding.

[0909] FIG. 319. Exemplary processes for forming MOF with Zr.sub.6O.sub.4(OH).sub.4 metal clusters from benzene-1,2,4,5-tetracarboxylic acid (H.sub.4BTC) and zirconium(IV) chloride (ZrCl.sub.4).

[0910] FIG. 320. Graphical representation of zinc acetate metal complex (Zn.sub.4O(CH.sub.3CO.sub.2).sub.6) with CN=4.

[0911] FIG. 321. Exemplary process for synthesizing ferrous MOF modified ion exchange ionomer Fe-MIL-101-NH.sub.2PPOSO.sub.2Cl from poly phenylene oxide sulfuryl chloride (PPO-SO.sub.2Cl) and amine metal oxide framework (C.sub.24H.sub.15ClFe.sub.3N.sub.3O.sub.13).

[0912] FIG. 322. Exemplary process for synthesizing chromium terephthalate metal cluster MIL-101(Cr).

[0913] FIG. 323. Graphical comparison of ligands in metal oxide frameworks (MOFs) with varying ratios of proton sources (OS) to proton hopping sites (PHS).

[0914] FIG. 324. Graphical representation of inventive heterogenous MOFs comprising catalyst and scavenger metals include scavengers located on metal sites (left), ligands (center), and guests (right).

[0915] FIG. 325. Graphical representation of inventive heterogenous MOFs comprising catalyst and scavenger metals arranged in interleaved planes without guests.

[0916] FIG. 326. Graphical representation of inventive heterogenous MOFs comprising catalyst and scavenger metals arranged in interleaved planes with intercalated guests (left) and stacked guests (right).

[0917] FIG. 327. Excerpted periodic table of elements highlighting transition metals aka D-block elements including platinum noble metal groups, the table illustrating atomic numbers, exemplary orbitals, and elemental RoHS risks of toxicity, safety, and radioactivity.

[0918] FIG. 328. Graph of bonding dissociation energies for select period 4, 5, and 6 transition metals.

[0919] FIG. 329A. Chemical representations of heterogenous M-L-M bonding identifying organic ligands applicable for Fe-to-Pt MOFs including metal dithiolene, metal 1,2-ethanedithiol, and metal pyridoxal-thiosemicarbazone.

[0920] FIG. 329B. Chemical representations of heterogenous M-L-M bonding identifying organic ligands applicable for Fe-to-Ti MOFs including metal Schiff base, metal salicylaldehyde, metal ethylenediamine.

[0921] FIG. 329C. Chemical representations of heterogenous M-L-M bonding identifying organic ligands applicable for Fe-to-Ti MOFs including metal imidazophenanthroline carboxylate and metal succinate.

[0922] FIG. 330A. Chemical representations of heterogenous M-L-M bonding identifying organic ligands applicable for Co-to-Pt MOFs including metal-1,2-bis(diphenylphosphino)ethane, metal bidentate phosphine, and metal-2,2-bipyridine.

[0923] FIG. 330B. Chemical representations of heterogenous M-L-M bonding identifying organic ligands applicable for Co-to-Pt MOFs including metal dithiolene, metal 1,2-ethanedithiol, and metal pyridoxal-thiosemicarbazone.

[0924] FIG. 331A. Chemical representations of heterogenous M-L-M bonding identifying organic ligands applicable for Ni-to-Pt MOFs including metal ambidentate, metal 1,2-bis(diphenylphosphino)ethane, and metal 2,2-bipyridine.

[0925] FIG. 331B. Chemical representations of heterogenous M-L-M bonding identifying organic ligands applicable for Ni-to-Ti MOFs including metal Schiff base, metal salicylaldehyde, and metal ethylenediamine.

[0926] FIG. 332. Pseudo-3D chemical representation of a zinc hexaphosphate ester based metal-organic framework illustrating guest molecular containment.

[0927] FIG. 333A. Process for MOF doping of polymer using inventive sacrificial filler method to form membrane vacancies to contain the dopant.

[0928] FIG. 333B. Pseudo-structural representation of an ion exchange membrane containing triazole-grafted poly(vinylbenzyl chloride) (C.sub.2H.sub.3N.sub.3-g-PVC) as an alternative to MOF fillers for high temperature PEMs.

[0929] FIG. 334. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising fluorocarbon and hydrocarbon polymers including such as PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI and CS, and variants thereof; including a sulfonated ionomeric membrane, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Metal organic framework (MOFs) fillers of varying geometric configurations include cubic, tetrahedral, double tetrahedral, hexagonal, octagonal, and planar sheets containing metals and metal complexes, functionalized by the metal complexes, ligands, or guests. Metal complexes include zinc-oxide hexaphosphate ester, chromium terephthalate, sulfonated ferrous clusters, zinc acetate, and zirconium based compounds such as Zr.sub.6O.sub.4(OH).sub.4. A novel class of heterogenous MOFs comprising a mix or catalytic or ionomeric metals with scavenger metals protecting the film from CO and toxic poisoning is also represented in varying intercalated and interleaved MOF geometries employing M-L-M ligands including M.sub.1-dithiolene-M.sub.2, M.sub.1-EDT-M.sub.2, M.sub.1-PLTSC-M.sub.2, M.sub.1-ambidentate-M.sub.2, M.sub.1-DPPE-M.sub.2, M.sub.1-BIPY-M.sub.2, M.sub.1-salicylaldehyde-M.sub.2, M.sub.1-Schiff bases-M.sub.2 and others.

[0930] FIG. 335. Exemplary process for synthesizing molybdenum-tungsten nanoparticles and their inclusion into or upon an ion exchange membrane.

[0931] FIG. 336. Molecular representation of phosphotungstic acid doped silica matrix.

[0932] FIG. 337. Exemplary process for synthesizing ferrocyanide-coordinated poly(4-vinylpyridine) (CP4VP) using water or methanol pathways.

[0933] FIG. 338. Molecular representation of ion exchange membrane comprising phosphotungstic acid (PWA) doped poly(4-vinylpyridine) (P4VP) polymers with ferrocyanide-coordinated poly(4-vinylpyridine) (CP4VP) ionomers embedded in a polysulfone (PSU, PSf) membrane.

[0934] FIG. 339. Molecular representation of ion exchange membrane comprising phosphotungstic acid (PWA) doped quaternized polyethyleneimine (QPEI) with R.sub.4N.sup.+ ionomers embedded in a poly vinyl alcohol (PVA) membrane.

[0935] FIG. 340. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising fluorocarbon and hydrocarbon polymers including such as PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI, and CS, and variants thereof such as poly(4-vinylpyridine) (P4VP) and quaternized polyethyleneimine (QPEI); including a ionomeric membrane comprising CP4VP, R.sub.4N.sup.+ and sulfonic ionomers, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Exemplary permanent tungsten fillers include molybdenum tungsten nanoparticles (Mo-W NPs) and phosphotungstic acid (PWA) crystals.

[0936] FIG. 341. Molecular and pseudo-structural representations of zeolite.

[0937] FIG. 342. Exemplary process depicting synthesis of sulfonic acid functionalized zeolite substrates using 2-(4-chlorosulfonilphenyl) ethyltrimethoxysilane (C.sub.11H.sub.17ClO.sub.5SSi).

[0938] FIG. 343. Exemplary process for bonding sulfonic acid onto a zeolite molecule via using 2-(4-chlorosulfonilphenyl) ethyltrimethoxysilane (C.sub.11H.sub.17ClO.sub.5SSi).

[0939] FIG. 344. Exemplary process depicting synthesis of sulfonic acid functionalized zeolite substrates using mercaptopropyltrimethoxysilane (C.sub.6H.sub.16O.sub.3SSi).

[0940] FIG. 345. Pseudo-structural representation of zeolite identifying various bonding regions.

[0941] FIG. 346. Pseudo-structural representation of various zeolite crystals.

[0942] FIG. 347. Pseudo-structural representation of zeolite identifying main, side, and link channels having differing pore sizes.

[0943] FIG. 348. Exemplary process for synthesis of sulfonated mordenite using a silane linker.

[0944] FIG. 349. Exemplary process for synthesis of zeolite nanoparticles housing catalytic or ionomeric guests.

[0945] FIG. 350. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising fluorocarbon and hydrocarbon polymers including such as PFSA, PFSA-PTFE, SPAES, SPEEK, PVA, PBI, and CS, and variants thereof; including a ionomeric membrane comprising sulfonic ionomers, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Zeolite fillers shown include phenyl zeolite, sulfonated mordenite, sulfonated zeolite substrates, and functionalized zeolite nanoparticles.

[0946] FIG. 351. Chemical representation of various sulfone moieties including polyether sulfone (PES), Udel polysulfone (PSU, PSf), and polyphenyl sulfone (PPSf, PPSU).

[0947] FIG. 352. Exemplary process for sulfonating Udel polysulfone into sulfonated polysulfone (sPSf, PPSU).

[0948] FIG. 353. Exemplary process for bromating Udel polysulfone into bromated polysulfone (BrPSf, BrPSU).

[0949] FIG. 354. Exemplary process for cross-linking bromated polysulfone into para-linked bromated polysulfone (BrPSf).sub.x or (BrPSU).sub.x.

[0950] FIG. 355. Exemplary process for synthesizing Udel polysulfone from 4,4-dichlorodiphenyl sulfone.

[0951] FIG. 356. Alternate process for sulfonating Udel polysulfone into sulfonated polysulfone (sPSf, sPSU).

[0952] FIG. 357. Exemplary process for synthesizing functionalized polymer graphene oxide sulfonated polysulfone (FPGO-sPSU, FPGO-sPSf) from sulfonated polysulfone and graphene oxide including resulting GO topography therefrom.

[0953] FIG. 358. Detailed chemical representation of functionalized polymer graphene oxide sulfonated polysulfone (FPGO-sPSU, FPGO-sPSf) with inset showing GO topography.

[0954] FIG. 359. Exemplary process for synthesizing platinum titanium dioxide nanoparticles (Pt-TiO.sub.2 NPs) from chloroplatinic acid hydrate and titanium dioxide.

[0955] FIG. 360. Schematic representation of a polysulfone (PSU, PSf) membrane containing sulfonated polysulfone polymeric chains with sulfonic acid ionomers, and with Pt-Ti nanoparticles and graphene oxide sulfone (FPGO-sPSU, FPGO-sPSf) fillers. Arrows indicate proton charge transport involves charge hopping among heterogenous conductors including the sulfonic acid ionomers, platinum nanoparticles, and functionalized graphene oxides.

[0956] FIG. 361. Schematic representation of an alternative polysulfone (PSf, PSU) membrane of sulfonated polysulfone polymeric chains with sulfonic acid ionomers containing polyoctahedral silsesquioxanes (POSS) fillers. Arrows indicate two forms of charge transportcharge hopping among HSO.sub.3 ionomers, and vehicular transport of hydronium ions assisted by POSS fillers.

[0957] FIG. 362. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising fluorocarbon and hydrocarbon polymers including such as sPSU or BrPSU or alternatively PFSA, PFSA-PTFE, PVA, SPAES, SPEEK, PBI and CS and variants thereof; including a ionomeric membrane comprising sulfonic ionomers, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Permanent fillers include polyoctahedral silsesquioxanes (POSS), platinum titanium dioxide nanoparticles (Pt-TiO.sub.2 NPs), and graphene oxide sulfone (FPGO-sPSU).

[0958] FIG. 363. Exemplary process for synthesizing a protic ionic liquid (PIL) comprising 1-hexyl-3-vinylimidazoliumdihydrogen phosphate (PHVlm-H.sub.2PO.sub.4).

[0959] FIG. 364. Exemplary process for synthesizing 2,2-(p-oxydiphenylene)-5,5-bibenzimidazole (OPBI).

[0960] FIG. 365. Exemplary process for forming a OPBI membrane with dihydrogen phosphate doping and a polymeric mainchain comprising poly [2,2-(p-oxydiphenylene)-5,5-bibenzimidazole].

[0961] FIG. 366. Exemplary process for synthesizing poly(arylene ether benzimidazole) (PAEBI).

[0962] FIG. 367A. Process flow for forming phosphoric acid functionalized PBI.

[0963] FIG. 367B. Chemical formula for phosphoric acid functionalizes PBI

[0964] FIG. 367C. Chemical representation of various forms of sulfonated poly (p-oxydiphenylene)-bibenzimidazole illustrating different bonding HSO.sub.3 configurations.

[0965] FIG. 368A to 368B. Chemical representations of various forms of un-functionalized bibenzimidazole including ABPI, p-PBI or m-PBI, 2OH-PBI, and F.sub.6PBI, SO.sub.2PBI, O-PBI, and 20-PBI.

[0966] FIG. 369. Chemical representation of cross linking of two PBI chains.

[0967] FIG. 370. Exemplary process for synthesizing PBI with sulfone pendant.

[0968] FIG. 371. Chemical representations of PBI linker molecules including DBpX, C.sub.8H.sub.8Cl.sub.2, (CH.sub.2CH).sub.2SO, B.sub.3Br, Be.sub.3Br, and C.sub.14H.sub.13NO.

[0969] FIG. 372. Process flow for partial crushing electrospun extruded PBI nanofibers and subsequent molding.

[0970] FIG. 373. Exemplary process for synthesizing hexachlorocyclotriphosphazene (HCCP) and imidazolechlorocyclotriphosphazene (ImCCP).

[0971] FIG. 374. Exemplary process for fabricating an phosphorated membrane comprising a copolymer of OPBI and poly(vinylbenzyl chloride) (PVBC) using quaternary ammonia.

[0972] FIG. 375. Chemical representation of a cross-linked copolymer of OPBI and poly(vinylbenzyl chloride) (PVBC) with quaternary ammonia moieties of quinuclidinol, quinuclidine, and DABCO.

[0973] FIG. 376. Pseudo-structural representation of ion exchange membrane comprising cross linked OPBI and polyaniline (PANI) functionalized by quaternary ammonia (QA), dihydrogen phosphate, and diphosphate-QA pairs.

[0974] FIG. 377. Exemplary process for fabricating a copolymer of PBI and a zeolitic imidazolate framework (ZIF).

[0975] FIG. 378. Pseudo-structural representation of ion exchange membrane comprising cross linked PBI and ZIF copolymers.

[0976] FIG. 379. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; polymer mainchains comprising hydrocarbon polymers of poly phenylene)-bibenzimidazole variants OPBI, ABPBI, p-PBI/m-PBI, 2OH-PBI, F.sub.6PBI, SO.sub.2PBI, 2OH-PBI, poly(arylene ether benzimidazole) (PAEBI), poly(vinylbenzyl chloride) (PVBC), polyaniline (PANI), PBI copolymers with zeolitic imidazolate frameworks (ZIFs), cross linked OPBI and polyaniline (PANI), or alternatively PFSA, PFSA-PTFE, PVA, SPAES, SPEEK, and CS and variants thereof; including a ionomeric membrane comprising sulfonic or diphosphate ionomers, pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Permanent fillers include electrospun PBI or OPBI nanofibers bound to hexachlorocyclotriphosphazene (HCCP) or imidazolechlorocyclotriphosphazene (ImCCP), quaternary ammonia ionomers and linkers including quinuclidinol, quinuclidine, and DABCO moieties.

[0977] FIG. 380. Three exemplary biopolymerschitosan (CS), cellulose (CE), and alginic acid (AA).

[0978] FIG. 381. Exemplary process for forming chitosan (CS) from chitin including one N-acetyl-D-glucosamine and two stereo isomer D-glucosamine segments.

[0979] FIG. 382. Exemplary process to sulfonate chitosan using acetic sulfate.

[0980] FIG. 383. Exemplary process to sulfonate and crosslink chitosan chains using sulfuric acid.

[0981] FIG. 384. Exemplary process to sulfonate chitosan using sulfosalicylic acid.

[0982] FIG. 385A. Exemplary process to phosphorylate chitosan using phosphoric acid.

[0983] FIG. 385B. Exemplary process to phosphorylate chitosan using a blend of triethyl phosphate, phosphoric acid, and phosphorus pentoxide.

[0984] FIG. 385C. Exemplary process to phosphorylate chitosan using a blend of methanesulfonic acid and phosphorus pentoxide.

[0985] FIG. 386. Exemplary process for synthesizing a protic ionic liquid (PIL) comprising 1-hexyl-3-vinylimidazoliumdihydrogen phosphate (PHVlm-H.sub.2PO.sub.4).

[0986] FIG. 387. Chemical representation of a functionalized copolymer comprising chitosan-co-polyacrylonitrile (CS-co-PAN).

[0987] FIG. 388. Chemical representation of a functionalized copolymer comprising chitosan-co-polystyrene (CS-co-PS).

[0988] FIG. 389. Chemical representation of a functionalized copolymer comprising chitosan-co-polyvinyl alcohol (CS-co-PVA).

[0989] FIG. 390. Chemical representation of a functionalized copolymer comprising chitosan-co-perfluorinated sulfonic acid (CS-co-PFSA).

[0990] FIG. 391. Graphical representation of proton conduction in a direct methanol fuel cell comprising the functionalized copolymer chitosan-co-perfluorinated sulfonic acid (CS-co-PFSA).

[0991] FIG. 392. Exemplary process to form vinylpyridine grafted chitosan (CS-g-PVP).

[0992] FIG. 393. Exemplary process to attach vinylpyridine grafted chitosan onto carboxylated carbon nanotube (CS-g-PVP-CNT).

[0993] FIG. 394. Exemplary process to form styrenesulfonic acid grafted chitosan (CS-g-SSA).

[0994] FIG. 395. Exemplary process to attach styrenesulfonic acid grafted chitosan onto carboxylated carbon nanotube (CS-g-SSA-CNT).

[0995] FIG. 396. Chemical representation of polyhedral oligomeric silsesquioxanes cross-linked chitosan chains (POSS XL-CS).

[0996] FIG. 397. Exemplary process to fabricate a nanochain comprising a sulfonated copolymer of polydopamine (PDA) with (3-(3-aminopropyl) dimethylammonio) propane-1-sulfonate (ADPS).

[0997] FIG. 398. Schematic representation of the structural composition and conduction mechanisms of a copolymer of sulfonated chitosan and nanochains of polydopamine and ADPS (sCS-co-PDA-co-ADPS-SA).

[0998] FIG. 399A. Chemical formulaic representation of a copolymer of cross-linked chitosan and polydopamine (CS-co-PDA) using a glutaraldehyde (GA) cross linker.

[0999] FIG. 399B. Chemical formulaic representation of a copolymer of cross-linked chitosan and functionalized polydopamine (CS-co-PDA) using a glutaraldehyde (GA) cross linker, where radical R may comprise sulfonic acid, phosphoric acid, or other ionomers.

[1000] FIG. 400. Structural representation sulfonated graphene oxide (sGO) filler for chitosan homopolymer membrane (CS).

[1001] FIG. 401A. Exemplary process for forming a grafted copolymer of cellulose acetate (CA) with sulfonated acrylamido methyl propane (AMPS) and methyl methacrylate (MMA).

[1002] FIG. 401B Chemical comparison between a homo-ionomeric IEM comprising P(MMA-co-AMPS) grafted to sulphonated cellulose acetate (sCA) versus a co-ionomeric dual-acid IEM where P(MMA-co-AMPS) is grafted onto phosphorylated cellulose acetate (pCA).

[1003] FIG. 402. Summary of exemplary inventive elements in fabricated ion exchange membrane including support skeleton; biopolymers of chitosan (CS), cellulose (CE), cellulose acetate (CA), alginic acid (AA), and variants thereof; including sulfonated and phosphorylated functional groups forming an ionomeric membrane, a pillar link bridging membrane to endoskeleton, and pores created by sacrificial fillers. Chitosan copolymers and grafts include polyacrylonitrile PAN, polystyrene (PS), polyvinyl alcohol (PVA), perfluorinated sulfonic acid (PFSA), vinylpyridine (PVP), polydopamine (PDA), polydopamine-co-(3-(3-aminopropyl) dimethyl-ammonium) propane-1-sulfonate (PDA-co-AMPS). Exemplary cellulose grafts include cellulose acetate-g-methyl methacrylate-co-2-acrylamido-2-methyl propane sulfonic acid (CA-g-P(MMA-co-AMPS). Permanent fillers and dopants include sulfonated or phosphorylated graphene oxide (sGO, pGO), chitosan grafted styrenesulfonic acid coated carbon nanotubes (CS-g-SSA-CNT), protic ionic liquids (PIL), polydopamine-co-ADPS-sulfonic acid nanochains (PDA-co-ADPS-SA NCs) and polyoctahedral silsesquioxanes (POSS). Biopolymer chain cross linkers include POSS, glutaraldehyde (GA), sulfonic acid (SA), and phosphoric acid (PA).

[1004] FIG. 403A. Synthesis of imidazolium ionic salt comprising 1-butyl-3-methyl-imidazolium chloride BMImCl.

[1005] FIG. 403B. Steps for converting an ionic salt into an ionic liquid comprising the IL cation [1-butyl-3-methylimidazolium]+ abbreviated [BMIm].sup.+ and the IL anion [hexafluorophosphate].sup. abbreviated [PF.sub.6].sup..

[1006] FIG. 403C. Methods of synthesis of secondary ionic liquids using acid-base neutralization and metal metathesis reactions.

[1007] FIG. 404A. Schematic cross sectional representation of proton exchange membrane comprising catalyst layers, polymer backbone, ionomers and ionic charge and reactants.

[1008] FIG. 404B. Schematic cross sectional representation of proton exchange membrane depicting structure with ionized protons and water but neglecting hydronium ions.

[1009] FIG. 404C. Schematic depiction of ionomer-to-ionomer hopping conduction in proton exchange membrane.

[1010] FIG. 405A. Schematic cross sectional representation of proton exchange membrane comprising catalyst layers, polymer backbone, ionomers, ionic charge and reactants including ionic liquid doped cations and anions.

[1011] FIG. 405B. Schematic depiction of hopping conduction mechanisms in ionic liquid doped proton exchange membrane including ionomer-to-ionomer, IL cation-to-cation, and ionomer-to-IL cation charge transport.

[1012] FIG. 406A. Chemical representations of exemplary ionic liquid cations comprising imidazolium, pyrrolidinium, and pyridinium radicals.

[1013] FIG. 406B. Chemical representation of other exemplary ionic liquid cations comprising ammonium, quaternary ammonium, and phosphonium radicals.

[1014] FIG. 406C. Chemical representation of other exemplary ionic liquid cations comprising sulfonium, thiazolium, and piperidinium radicals.

[1015] FIG. 406D. Chemical representation of other exemplary ionic liquid cations comprising alkanium, cholinium, and poly n-vinylimidazolium.

[1016] FIG. 407. Phase diagram representing the meting temperature of an ionic salt as a function of IL anion molar fraction.

[1017] FIG. 408. Exemplary anions present in ionic liquids.

[1018] FIG. 409A. Representative isomers and variants of imidazole and associated ionic liquids containing imidazolium cations.

[1019] FIG. 409B. Generalized scalable representation of 1-alkyl-3-methylimidazolium cations along with ethyl (n=2) and propyl (n=3) variants thereof.

[1020] FIG. 409C. Butyl (n=4), hexyl (n=6), and octyl (n=8) variants of 1-alkyl-3-methylimidazolium cations.

[1021] FIG. 410. Graph illustrating the dependence of the dissociation temperature T.sub.d of 1-alkyl-3-methylimidazolium ionic salts on alkyl chain length n.

[1022] FIG. 411A. Representative isomers and variants of pyrrolidine and associated ionic liquids containing pyrrolidinium cations including generalized scalable N-alkyl-N-methylpyrrolidinium.

[1023] FIG. 411B. Ethyl (n=1), methyl (n=2), and propyl (n=3) variants of N-alkyl-N-methylpyrrolidinium.

[1024] FIG. 411C. Isopropyl (n=3), butyl (n=4), and pentyl (n=5) variants of N-alkyl-N-methylpyrrolidinium

[1025] FIG. 412A. Representative isomers and variants of pyridine and associated ionic liquids containing pyridinium cations including generalized scalable alkylpyridinium.

[1026] FIG. 412B. Ethyl (n=1), methyl (n=2), and propyl (n=3) variants of alkylpyridinium cations.

[1027] FIG. 412C. Butyl (n=4), hexyl (n=6), and octyl (n=8) variants of alkylpyridinium cations.

[1028] FIG. 413A. Representative isomers and variants of ammonia and associated ionic liquids containing ammonium and primary substituted ammonium cations.

[1029] FIG. 413B. Representative moieties of secondary, tertiary, and quaternary substituted ammonium cations.

[1030] FIG. 413C. Methyl (n=2) variants of alkylpyridinium cations.

[1031] FIG. 413D. Generalized scalable N-tetraalkylammonium cation along with tetramethyl and tetraethyl moieties.

[1032] FIG. 413E. Tetrapropyl, tetrabutyl, and tetrahexyl moieties of ammonium cations.

[1033] FIG. 413F. Phenyl moieties of ammonium cations including tetraphenyl, phenyltrimethyl, and benzyltriethyl variants.

[1034] FIG. 413G. Phenyl moieties of ammonium cations including benzyltripropyl, benzyltributyl, and triethylmethyl variants.

[1035] FIG. 413H. Long-chain alkyl moieties of ammonium cations comprising dioctyldimethyl and dodecylethyldimethyl variants.

[1036] FIG. 413I. Long-chain alkyl moieties of ammonium cations comprising benzyldimethylstearyl and trimethylstearyl variants.

[1037] FIG. 413J. Moieties of ammonium cations comprising tetra(4-thiaalkyl) and hydroxyl variants.

[1038] FIG. 413K. Moieties of ammonium cations comprising triethanolammonium, N-oxoammonium, and aminoxl oxoammonium variants.

[1039] FIG. 414A. Representative isomers and variants of phosphine and associated ionic liquids containing phosphonium and primary-substituted methylphosphonium cations.

[1040] FIG. 414B. Representative moieties of secondary, tertiary, and quaternary substituted methylphosphonium cations along with a generalized scalable alkylphosphonium cation.

[1041] FIG. 414C. Moieties of phosphonium cations comprising methoxymethyltriphenyl, ethyltriphenyl, and butyltriethyl variants.

[1042] FIG. 414D. Moieties of phosphonium cations comprising butyldiethylmethyl, methylethylbiphenyl, and tetrakis(hydroxymethyl) variants.

[1043] FIG. 415A. Representative isomers and variants of sulfide and associated ionic liquids containing sulfonium cations including nascent, primary, secondary, and tertiary substituted variants.

[1044] FIG. 415B. Representative moieties of primary, secondary, and tertiary methyl substituted sulfonium cations.

[1045] FIG. 415C. Generalized scalable alkylsulfonium cation including alkyl, dialkyl, and trialkyl variants.

[1046] FIG. 415D. Moieties of sulfonium cations comprising tris(dimethylamino), triphenylsulfonium, and diphenylmethyl variants.

[1047] FIG. 415E. Moieties of sulfonium cations comprising diethylmethyl, triethyl, and diethylpropyl variants.

[1048] FIG. 416A. Representative isomers and variants of thiazole and associated ionic liquids containing thiazolium cations including quad-radical, mono-radical basic, and mono-alkyl or dialkyl functional groups.

[1049] FIG. 416B. Moieties of thiazolium cations comprising mono-radical hydroxyethyl, tri-radical ethyl-hydroxyethyl-methyl, tri-radical benzyl-hydroxyethyl-methyl, and dimethylnaphtho variants.

[1050] FIG. 416C. Moieties of thiazolium cations comprising mono-radical benzothiazolium, di-radical dimethyl benzothiazolium, di-radical ethyl-methyl benzothiazolium, and phenacylthiazolium.

[1051] FIG. 417A. Representative isomers and variants of piperidine and associated ionic liquids containing piperidinium cations including monovalent moieties comprising two functional groups of hydrogen, two functional groups of radicals R, and N-alkyl-N-methylpiperidinium.

[1052] FIG. 417B. Methyl (n=1), propyl (n=3), and butyl (n=4) variants of N-alkyl-N-methylpiperidinium.

[1053] FIG. 418A. Moieties of carbonium cations comprising methanium, protonated methanol, and ethanium.

[1054] FIG. 418B. Moieties of carbonium cations comprising protonated ethanol, butanium, and protonated acetone.

[1055] FIG. 418C. Moieties of carbonium cations comprising protonated acetonitrile, protonated dimethyl sulfoxide, and protonated aniline.

[1056] FIG. 419. The chemical structure of biochemical cations of ionic liquids comprising cholinium, creatininium, and lysinium.

[1057] FIG. 420. Exemplary superbases applicable in ionic liquids comprising enium, phosphazene, and cyclopropenium cations.

[1058] FIG. 421. Exemplary cations of polymer ionic liquids (PILs) comprising variants of vinyl pyrrolidinium.

[1059] FIG. 422A. Fabrication sequence for forming ion exchange membranes with micropores using sacrificial fillers.

[1060] FIG. 422B. Process steps for doping microporous membranes with ionic liquid.

[1061] FIG. 422C. Ionic liquid doped microporous ion exchange membrane sealed by nanocoating.

[1062] FIG. 423. Exemplary steps in fabricating an ion exchange membrane containing permanent fillers, sacrificial filler formed micropores, ionic liquid doping, and nanocoating sealant.

[1063] FIG. 424. Process sequence for forming a nanocoated IL-doped microporous IEM with embedded permanent fillers.

[1064] FIG. 425. Comparison of IL-doping of conventional IEMs to endoskeletal reinforced membranes using a pancake versus waffle analogy.

[1065] FIG. 426. A topological summary of various types of block polymers.

[1066] FIG. 427A. Process to form a block polymer using a excision-insertion reaction.

[1067] FIG. 427B. Process to form a block polymer using a modified ring opening polymerization.

[1068] FIG. 427C. Process to form a block polymer using a nucleophilic aromatic substitution reaction.

[1069] FIG. 427D. Process to form a block polymer using atomic transfer radical polymerization.

[1070] FIG. 427E. Process to form a block polymer using cross-linker polymerization.

[1071] FIG. 428A. Chemical structure and block map of a sulfonated styrene penta-block copolymer.

[1072] FIG. 428B. Chemical structure and block map of a sulfonated styrene quad block copolymer.

[1073] FIG. 428C. Chemical structure and block map of a sulfonated phenyl mirrored quad block copolymer.

[1074] FIG. 428D. Chemical structure and block map of sulfonated arylene ether sulfone alternating di-block copolymers.

[1075] FIG. 428E. Chemical structure and block map of sulfonated arylene ether sulfone random multi-block copolymers.

[1076] FIG. 428F. Chemical structure and block map of a sulfonated polystyrene branched multi-block copolymer.

[1077] FIG. 428G. Chemical structure and block map of a sulfonated poly(phenylene oxide) branched multi-block copolymer.

[1078] FIG. 428H. Chemical structure and block map of a sulfonated polytriazole sidechain in a comb multi-block copolymer.

[1079] FIG. 428I. Chemical structure and block map of a R functionalized polysulfone sidechain block copolymer.

[1080] FIG. 428J. Chemical structure and block map of a poly(sulfide ketone) sulfonated hexaphenyl tri-block copolymer.

[1081] FIG. 428K. Chemical structure and block map of a poly(ether sulfone) decaphenyl sulfonic acid alternating block copolymer.

[1082] FIG. 428L. Chemical structure and block map of a sulfonated polyphenyl sidechain tri-block copolymer.

[1083] FIG. 429A. Quasi-3D representation of an semi-amorphous ionomeric film comprising two copolymers structurally bound by supportive endoskeletal pillars, where the pillars contain carbon filler or other reinforcing materials.

[1084] FIG. 429B. Schematic representation comparing homopolymers and copolymers containing homo-ionomers and hetero-ionomers.

[1085] FIG. 429C. Quasi-3D representation of individual ionomeric strands comprising an ionomeric film and an exemplary amorphous polymer matrix resulting therefrom.

[1086] FIG. 429D. Quasi-3D representation of a ionomeric film comprising two copolymers structurally bound to surrounding endoskeletal pillars, where naturally-occurring pores are present interstitially within a semi-amorphous polymer matrix.

[1087] FIG. 429E. Simplified quasi-3D representation of a semi-amorphous ionomeric film comprising two copolymers structurally bound by endoskeletal pillars illustrating naturally occurring pores. For clarity's sake the polymer strands and pillar fillers are not shown.

[1088] FIG. 429F. Simplified quasi-3D representation of a ionomeric film comprising a semi-amorphous ionomeric film comprising two copolymers structurally bound to endoskeletal pillars, where the membrane contains both naturally-occurring interstitial pores along with sac pores made by sacrificial fillers. For clarity's sake the polymer strands and pillar fillers are not shown.

[1089] FIG. 429G. Quasi-3D representation of a densely-packed ionomeric film comprising a semicrystalline homopolymer and associated endoskeletal pillars illustrating small nanopores present interstitially within the polymer matrix.

[1090] FIG. 429H. Simplified quasi-3D representation of a dense ionomeric film comprising a semicrystalline homopolymer highlighting naturally occurring nanopores present interstitially withing the matrix. For clarity's sake the polymer strands and pillar fillers are not shown.

[1091] FIG. 429I. Simplified quasi-3D representation of a dense ionomeric film comprising a semicrystalline homopolymer with supporting endoskeletal pillars, where the membrane includes naturally-occurring nanopores along with larger sac pores made by sacrificial fillers. For clarity's sake the polymer strands and pillar fillers are not shown.

[1092] FIG. 429J. Simplified quasi-3D representation of a semi-amorphous membrane with supporting endoskeletal pillars illustrating a combination of naturally-occurring interstitial pores combined with permanent fillers where the average filler size is larger than the naturally occurring pores. For clarity's sake the polymer strands and pillar fillers are not shown.

[1093] FIG. 429K. Simplified quasi-3D representation of a semi-amorphous membrane with supporting endoskeletal pillars illustrating a combination of naturally occurring pores combined with sac pores made by sacrificial fillers and with permanent fillers where the average filler size is larger than the naturally occurring and sacrificial pores. For clarity's sake the polymer strands and pillar fillers are not shown.

[1094] FIG. 429L. Simplified quasi-3D representation of a semi-amorphous membrane comprising a homopolymer or two-or-more copolymers with supporting endoskeletal pillars illustrating a combination of naturally-occurring interstitial pores combined with sac pores made by sacrificial fillers and with small permanent fillers or dopants present in matrix where the average filler size is smaller than the naturally-occurring and sacrificial pores. For clarity's sake the polymer strands and pillar fillers are not shown.

[1095] FIG. 429M. Simplified quasi 3D representation semi-amorphous membrane comprising a homopolymer or two-or-more copolymers with supporting endoskeletal pillars illustrating the combination of naturally-occurring pores and sac pores made by sacrificial fillers combined doped with ionic liquids. As depicted the ionic liquid present interstitially throughout the membrane pools in greater concentrations with natural and sac pores.

[1096] FIG. 430. An exemplary summary of various versions of ionomeric polymer membranes made in accordance with this invention including an exemplary list of ionomer types made of homopolymers, fluorocarbon di-monomers, hydrocarbon di-monomers, hydrocarbon multi-polymers, hydrocarbon heteropolymers, hydrocarbon copolymers, anhydrous polymers and biopolymers, and block polymers.

[1097] FIG. 431A. Exemplary chemical representations of hydrocarbon homopolymers made in accordance with this invention including sulfonated polyphenylene, sulfonated phenyl-aldehyde, sulfonated covalent triazine polymer, and phosphorylated polyvinyl alcohol.

[1098] FIG. 431B. Other exemplary chemical representations of hydrocarbon homopolymers made in accordance with this invention including polystyrene-sulfonated polystyrene, sulfonated polysulfone, sidechain sulfonated poly(benzoyl-phenylene), and linear sulfonated poly(trifluorostyrene).

[1099] FIG. 431C. Exemplary chemical representations of hydrocarbon ionomers made in accordance with this invention including the homopolymer poly(ether imide) and a linear copolymer of sulphonated poly(arylene ether sulfone) triazine bisphenol moieties.

[1100] FIG. 431D. Exemplary chemical representations of fluorocarbon ionomers comprising linearly-arranged heterogenous di-monomers made in accordance with this invention including a compound reinforced membrane of perfluorinated sulfonic acid polytetrafluoroethylene, poly(perfluoro-methylene-methyl-dioxolane), sulfonated fluorinated glassy matrices, and perfluoro imide acid.

[1101] FIG. 431E. Exemplary chemical representations of hydrocarbon copolymers comprising linearly-arranged heterogenous di-monomers made in accordance with this invention including maleic anhydride poly(methyl methacrylate) (MAH-PMMA), sulfonated polyethylene, sulfonated polyvinyl chloride, and sulfonated phenylsulfonyl-poly(benzoyl-phenylene).

[1102] FIG. 431F. Exemplary chemical representations of hydrocarbon copolymers comprising heterogenous di-monomers made in accordance with this invention including linearly-arranged poly sulfonated phosphazene-co-poly phosphazene and poly sulfonated siloxane-co-siloxane, along with cross-linked sulfonated polystyrene.

[1103] FIG. 431G. Exemplary chemical representations of linearly-arranged heterogenous hydrocarbon copolymers made in accordance with this invention including sulfonated polyimide and sulfonated poly(fluorenyl ether ketone nitrile).

[1104] FIG. 431H. Exemplary chemical representations of linearly-arranged heterogenous hydrocarbon-fluorocarbon blended copolymers made in accordance with this invention including sulfonated fluorinated polyethersulfone and sulfonated poly(arylene ether sulfone).

[1105] FIG. 431I. Exemplary chemical representations of heterogenous hydrocarbon copolymers made in accordance with this invention comprising linearly arranged poly arylene ether (sP6F9CB) and the comb copolymer thermoplastic urethane-co-sulfonated divinyl benzene.

[1106] FIG. 431J. Exemplary chemical representations of linearly-arranged heterogenous fluorocarbon copolymers made in accordance with this invention including perfluoro-methylene-methyl-dioxolane-co-perfluoro-methylene-dioxolane, perfluoro-methylene-methyl-dioxolane-co-chlorotrifluoroethylene, perfluoro-methylene-methyl-dioxolane-SA-co-perfluorostyrene, and poly(dioxodihydropyrrole-co-carbonyl sulfonyl fluoride-co-styrene-SA.

[1107] FIG. 431K. Exemplary chemical representations of linearly-arranged heterogenous hydrocarbon copolymers made in accordance with this invention including sulfonated polyphenylene-co-quaterphenol and sulfonated polyamide-co-sulfonimide.

[1108] FIG. 431L. Exemplary chemical representations of heterogenous hydrocarbon copolymers made in accordance with this invention including cross-linked sulfonated polyvinyl alcohol, polyvinylidene fluoride-co-sulfonated polyvinyl alcohol; and hydrocarbon-fluorocarbon blended multi-polymer polyvinylidene fluoride-co-perfluorosulfonic acid.

[1109] FIG. 431M. Exemplary chemical representations of heterogenous hydrocarbon multipolymers made in accordance with this invention including sulfonated poly(ether ketone) and sulfonated poly(ether sulfone) sequenced linear copolymers sPE.sub.xK.sub.y and sPE.sub.x(Sf).sub.z respectively.

[1110] FIG. 431N. Exemplary chemical representations of heterogenous hydrocarbon multipolymers made in accordance with this invention including sulfonated poly(ketone sulfone) and sulfonated poly(arylene ether ketone sulfone) sequenced linear copolymers sP(K.sub.y(Sf).sub.z) and sP(A.sub.wE.sub.xK.sub.y(Sf).sub.z) respectively. In both exemplary moieties, only the ketone group is sulphonated.

[1111] FIG. 431O. Exemplary chemical representations of heterogenous hydrocarbon multipolymers made in accordance with this invention including polyvinyl difluoride-co-polyvinyl pyrrolidone-co-polystyrene sulfonic acid (SA) and polyvinylidene fluoride-co-polyvinylidene pyrrolidone SA.

[1112] FIG. 431P. Exemplary chemical representations of heterogenous hydrocarbon multipolymers made in accordance with this invention including tri-polymer polyvinylidene fluoride-co-azobisiso butyronitrile-co-sulfopropyl acrylate, bi-polymer polyvinylidene fluoride-co-hexafluoro propylene, and quarte-polymer polyvinylidene fluoride-co-azobisiso butyronitrile-co-sulfopropyl acrylate-co-hexafluoropropylene.

[1113] FIG. 431Q. Exemplary chemical representations of heterogenous fluorocarbon multi-polymers made in accordance with this invention including graft poly(perfluoroalkoxy alkane)-g-polystyrene sulfonic acid, and cross linked copolymer chains of sulfonated poly(trifluorostyrene).

[1114] FIG. 431R. Exemplary chemical representations of membranes made in accordance with this invention including heterogenous biopolymers of poly(dopamine-sulfonated dopamine) and D-glucosamine SA based sulfonated chitosan; along with anhydrous polymers comprising variants of sulfonated poly phenylene bibenzimidazole.

[1115] FIG. 432A. Proton exchange membrane attached homo-ionomers made in accordance with this invention comprising negatively charged anions of acids, hydroxides, and amide groups.

[1116] FIG. 432B. Additional proton exchange membrane-attached homo-ionomers made in accordance with this invention comprising negatively charged anions of acids and phosphates.

[1117] FIG. 432C. Proton exchange membrane attached ionomers hetero-ionomers made in accordance with this invention comprising acid and hydroxide combinations.

[1118] FIG. 432D. Proton exchange membrane attached ionomers hetero-ionomers made in accordance with this invention comprising acid and phosphate combinations.

[1119] FIG. 432E. Response curves showing superposition of co-ionomer characteristics.

[1120] FIG. 433A. Chemical and structural representations of permanent IEM fillers and dopants made in accordance with this invention including bismuth compounds, graphene oxides, carbon nanotubes including pristine, nanocoated, or functionalized variants. CNT surface treatments comprise amino, silica, titania, hydroxy-phosphoric, carboxyl, and acid groups such as sulfonic acid.

[1121] FIG. 433B. Chemical and structural representations of other permanent IEM fillers and dopants made in accordance with this invention including silicates, nano structures and particles, zirconium, metal organic frameworks (MOF), tungsten, zeolite, and polyoctahedral silsesquioxanes compounds.

[1122] FIG. 433C. Cations of various ionic liquids made in accordance with this invention.

[1123] FIG. 434A. Simplified block diagram of a static array buffered fuel cell.

[1124] FIG. 434B. Simplified block diagram of a dynamic array buffered fuel cell with buffer load access output port protection.

[1125] FIG. 434C. Simplified block diagram of a dynamic array buffered fuel cell with buffer load access output port protection and electrical power input via energy recovery modulation.

[1126] FIG. 435. Energy input and outputs in iBFC applications.

[1127] FIG. 436. Schematic of iBFC electrical elements including fuel cell stack, electrical buffer, charger, and load protection.

[1128] FIG. 437A. BLA buffer load access bidirectional blocking switch implementation comprising four terminal lateral MOSFET with body bias generator.

[1129] FIG. 437B. BLA buffer load access bidirectional blocking switch implementation comprising common source and common drain trench power DMOSFETs.

[1130] FIG. 438. Improved BLA buffer load access comprising a three power MOSFET implementation of bidirectional disconnect and bypass switch functions.

[1131] FIG. 439. Block diagram of iBFC intelligent buffered fuel cell modules and functions.

[1132] FIG. 440. Power loss in resistive devices as a function of input power from a 4V, 24V and 48V source.

[1133] FIG. 441. Schematic of a 24V iBFC comprising a dynamic fuel cell array with buffer cell balancing.

[1134] FIG. 442. Fuel cell stack voltage as a function of individual fuel cell V.sub.FC comprising stacks with n=21, n=42,or n=63.

[1135] FIG. 443. iBFC operation of a dynamic fuel cell switching between n=63 and n=42 including hysteresis.

[1136] FIG. 444. Top view of exemplary 24V iBFC including three stacks of 21 PEM+fuel cells.

[1137] FIG. 445. End view of exemplary 24V iBFC comprising three stacks of 21 PEM+fuel cells.

[1138] FIG. 446. Cutline view of 6s1p buffer cells within exemplary 24V iBFC.

[1139] FIG. 447. Perspective view of 6s3p buffer cells in exemplary 24V iBFC module.

[1140] FIG. 448. Exterior view of exemplary 24V iBFC.

[1141] FIG. 449. Schematic of 4 stack 24V iBFC module.

[1142] FIG. 450. Voltage-current transfer characteristics of a dual-mode dynamic buffered fuel cell.

[1143] FIG. 451. FC stack voltage dependence on individual membrane voltages VFC as function of stack height n.sub.FC.

[1144] FIG. 452. Schematic comparison of two-zone and three-zone five-stack buffered fuel cells.

[1145] FIG. 453. Voltage-current transfer characteristics of a dual-mode dynamic buffered fuel cell comparing n.sub.FC={36, 60}.

[1146] FIG. 454. Voltage-current transfer characteristics of a three-mode dynamic buffered fuel cell comparing n.sub.FC={36, 48, 60}.

[1147] FIG. 455. Components of a buffered fuel cell including charge transfer regulator driving a summing node, with a charge transfer regulator limiting the buffer voltage balanced across cells.

[1148] FIG. 456. Details of a charge transfer regulator in a buffered fuel cell driving a shared summing node.

[1149] FIG. 457. Details of a charge transfer regulator in a buffered fuel cell lacking a shared summing node.

[1150] FIG. 458. I-V characteristics of constant current charger and antiparallel current source bypass circuit.

[1151] FIG. 459. Calibration of BFC lumped element model.

[1152] FIG. 460. Schematic representation of various buffered fuel cells with a constant cell voltage V.sub.FC=0.7V.

[1153] FIG. 461. Stack voltages for various buffered fuel cells contrasting n.sub.FC=(36, 48, 601 as a function of fuel cell membrane voltage V.sub.FC.

[1154] FIG. 462. Schematic representation of various buffered fuel cells with a constant output voltage V.sub.L=25.2V.

[1155] FIG. 463. Scalable energy bank power architecture comprising a mainframe delivering hydrogen, oxygen, cooling, and power bussing to pluggable energy blades. In the example shown the energy blades generate 5 kW to 7 kW of power-on-demand, i.e. power for one hour at a 1 C rate, plus continuous power ranging from 1 kW to 4 kW available perpetually so long that hydrogen is suppled.

[1156] FIG. 464. Cross section of a stack fuel cell with gas supply routed through a temperature regulated backplate. Although a hydrogen gas circuit is shown, the backplate may also include oxygen or air supply, plus liquid cooling as required.

[1157] FIG. 465. Cross section illustrating the physical connection between a stack fuel cell and non-planar electrically-insulating thermally conductive backplate including gas transfer and requisite grommets to prevent hydrogen leakage.

[1158] FIG. 466A. Cross sectional representation of the starting material used for forming power blade backplates.

[1159] FIG. 466B. Cross sectional representation of the power blade backplate substrate after channel formation.

[1160] FIG. 466C. Cross sectional representation of the power blade backplate substrate illustrating the process step attaching insulating PCB comprising a single- or double-sided board attached to the thermally conductive substrate.

[1161] FIG. 466D. Cross sectional representation of the power blade backplate substrate illustrating an insulating PCB comprising a single- or double-sided board attached to the thermally conductive substrate with selective vias.

[1162] FIG. 466D. Cross sectional representation of the power blade backplate attached to printed circuit board illustrating both ports and buried gas conduits.

[1163] FIG. 466E. Cross sectional representation of the power blade backplate attached to printed circuit board illustrating both ports and buried gas conduits and including non-planar copper conductive traces.

[1164] FIG. 467. Cross sectional representation of the power blade backplate attached to printed circuit board illustrating the role of a grommet to prevent gas leakage.

[1165] FIG. 468A. Cross sectional representation of the power blade backplate attached to printed circuit board illustrating both ports and buried gas conduits and including coplanar copper conductive traces.

[1166] FIG. 468B. Cross sectional representation of the power blade backplate with printed circuit board, buried gas conduits, coplanar copper conductive traces directly bonded to stack fuel cell assembly.

[1167] FIG. 469. Cross sectional representation of a stack fuel cell assembly illustrating gas transport from and back into a planarized backplate.

[1168] FIG. 470. Cross sectional representation of a backplate containing a cooling coil for uniform temperature regulation of a PCB and attached stack fuel cell modules. A thermally conductive backplate core is excluded from the illustration.

[1169] FIG. 471. Graph comparing the time dependent current characteristics I.sub.FC(t) of a battery pack versus the inventive buffered fuel cell in three operating modestransient, 1 C power-on-demand, and continuous operation where the number of cells for the battery pack and iBFC are equal. Note that batteries are incapable of continuous power delivery, but can only deliver PoD power for one hour at a IC discharge rate, after which current drops to zero. The buffered fuel cell deliver a higher average power during 1 C PoD discharge but after continues to deliver a steady state current indefinitely.

[1170] FIG. 472A. Plan view of an embodiment of a iBFC power blade comprising twelve 200 cm.sup.2 stack fuel cells and 96 buffer cells fit into a standard power blade dimension of 48.3 cm (19 in) wide and 76 cm (30 in) deep. The power blade delivers 5.2 kW of power-on-demand but a continuous power of 4 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 77%.

[1171] FIG. 472B. Plan view of an embodiment of a iBFC power blade comprising seven 200 cm.sup.2 stack fuel cells and 294 buffer cells fit into standardized power blade dimensions. The power blade delivers 6.0 kW of power-on-demand but a continuous power of 2.5 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 42%.

[1172] FIG. 472C. Plan view of an alternative embodiment of a BFC power blade comprising seven 200 cm.sup.2 stack fuel cells and 210 buffer cells fit into standardized power blade dimensions. For ease of comparison, the components are not repositioned on the PCB to benefit from the unused space. The power blade delivers 5.0 kW of power-on-demand but a continuous power of 2.5 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 50%.

[1173] FIG. 472D. Plan view of an embodiment of a iBFC power blade comprising six 200 cm.sup.2 stack fuel cells and 300 buffer cells fit into standardized power blade dimensions. For ease of comparison, the components are not repositioned on the PCB to benefit from the unused space. The power blade delivers 5.7 kW of power-on-demand but a continuous power of 2.0 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 35%.

[1174] FIG. 472E. Plan view of an alternative embodiment of a iBFC power blade comprising six 200 cm.sup.2 stack fuel cells and 240 buffer cells fit into standardized power blade dimensions. For ease of comparison, the components are not repositioned on the PCB to benefit from the unused space. The fuel cells and buffer cell may configured in two topologies offering qual power outputs offering either double the iBFC current of double the iBFC voltage of the other version. Regardless of its serial or parallel cell topology, either power blade delivers 5.0 kW of power-on-demand with a continuous power of 2.0 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 40%.

[1175] FIG. 472F. Plan view of an embodiment of a iBFC power blade comprising five 200 cm.sup.2 stack fuel cells and 280 buffer cells fit into standardized power blade dimensions. For ease of comparison, the components are not repositioned on the PCB to benefit from the unused space. The power blade delivers 5.2 kW of power-on-demand but a continuous power of 1.7 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 33%.

[1176] FIG. 472G. Plan view of an embodiment of a iBFC power blade comprising four 200 cm.sup.2 stack fuel cells and 296 buffer cells fit into standardized power blade dimensions. For ease of comparison, the components are not repositioned on the PCB to benefit from the unused space. The power blade delivers 5.0 kW of power-on-demand but a continuous power of 1.4 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 28%.

[1177] FIG. 472H. Plan view of an embodiment of a iBFC power blade comprising three 200 cm.sup.2 stack fuel cells and 480 buffer cells fit into standardized power blade dimensions, where the design occupies virtually the entire available PCB area. The battery heavy power blade delivers 7.0 kW of power-on-demand but a continuous power of 1.0 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 14%.

[1178] FIG. 472I. Plan view of an embodiment of a iBFC power blade comprising three 200 cm.sup.2 stack fuel cells and 336 buffer cells fit into standardized power blade dimensions. For ease of comparison, the components are not repositioned on the PCB to benefit from the unused space. The power blade delivers 5.2 kW of power-on-demand but a continuous power of 1.0 kW with a steady-state to on-demand P.sub.SS-to-PoD power ratio of 19%.

[1179] FIG. 473A. Graph of power output separately identifying buffer power P.sub.buf, steady-state fuel cell power P.sub.SS=P.sub.FC, and power-on-demand P.sub.PoD=P.sub.SS+P.sub.buf, for a spectrum of fuel cells comprising a power blade using a 3000 cm.sup.2 PCB, fractionally divided by competing areas of buffer cells A.sub.buf and fuel cells A.sub.FC.

[1180] FIG. 473B. Graph of power-on-demand P.sub.PoD for an iBFC power blade as a function of total buffer area A.sub.buf as a fraction of a PCB area A.sub.pcb=3000 cm.sup.2.

[1181] FIG. 473C. Graph of power-on-demand P.sub.PoD for an iBFC power blade as a function of total fuel cell area A.sub.FCf as a fraction of a PCB area A.sub.pcb=3000 cm.sup.2.

[1182] FIG. 473D. Graph of the continuous output power P.sub.SS of an iBFC power blade of total PCB area A.sub.pcb=3000 cm.sup.2 as a function of output power-on-demand P.sub.POD.

[1183] FIG. 473D. Graph of constituent power outputs of a 3000 cm.sup.2 iBFC power blade, including steady-state power P.sub.SS, power-on demand P.sub.PoD, and 10 second transient power P.sub.10s as a function of the number of buffer cells #buf. Calculations assume all board area not occupied by buffer cells contains fuel cell area.

[1184] FIG. 473D. Graph of constituent power outputs of a 3000 cm.sup.2 iBFC power blade, including steady-state power P.sub.SS, power-on demand P.sub.PoD, and 10 second transient power P.sub.10s as a function of the number of buffer cells #buf highlighting the none previously described iBFC designs.

[1185] FIG. 474. Hydrogen power system architecture comprising both a intelligent buffered water to hydrogen converter (iBH2WC) electrolyzer and a separate intelligent buffered fuel cell (iBFC) each with their own dedicated buffer cell array.

[1186] FIG. 475. Hydrogen power system architecture comprising both a unbuffered water to hydrogen converter (iBH2WC) electrolyzer powered by an intelligent buffered fuel cell (iBFC).

[1187] FIG. 476. Circuit illustrating a buffer water to hydrogen converter and electrolyzer.

[1188] FIG. 477. Circuit illustrating a unbuffered water to hydrogen converter and electrolyzer power by the buffer cells in the iBFC.

[1189] FIG. 478. Brief overview of inventive features in an advanced fuel cell with PEM+ membrane.

DESCRIPTION OF INVENTION

[1190] A new class of ion exchange membrane membranes is described created to ameliorate or eliminate the various deficiencies present in present day conventional fuel cells. Specifically this patent discusses innovations in proton exchange membranes (PEMs), also known a cation ion exchange membrane (CEMs), or hydrogen ion exchange membranes (H.sup.+ IEMs). Topics discussed include [1191] IEM structural support for improved handling and operational reliability [1192] Proton exchange membrane (PEM) for hydrogen fuel cell operation [1193] Proton exchange membrane (PEM) for hydrogen from water hydrolysis [1194] Proton exchange membranes for alternative uses, including filtering and dialysis [1195] Hydrogen ion exchange membranes for alternative uses [1196] Applications of improved IEMs

[1197] Specifically this patent concentrates on the improved implementation of proton ion exchange membranes using hydrogen as a fuel source as reflected in its title Advanced Hydrogen Ion Exchange Membranes and Applications Thereof. The various embodiments of inventions described and disclosed herein can be implemented individually or in combination.

[1198] Although the focus of this discussion is on membranes transporting cations comprising ionized hydrogen, i.e. protons, its should be understood the principles, methods, fabrication techniques, and applications of such hydrogen based IEM fuel cells and electrolyzers are not strictly limited to such narrowly defined topics, but may be applied to other types of fuel cells and electrolysis such as those employing methanol, methane, glucose or where ion transport across the membrane involves negatively charged anions.

[1199] Alternative IEMs and related innovations involving anion exchange membranes (AEMs) for fuel cells and hydrolysis; ion exchange membranes for glucose based fuel cells and electrolysis (Glu-IEMs), and ion exchange membranes (IEMs) for electrolysis of carbon compounds are explicitly considered in this application, but numerous inventive elements such as endoskeletal support apply.

Basic IEM Terminology.

[1200] Herewith, the use of the terms cation, proton, and hydrogen ion as the H.sup.+ or the hydronium ion H.sub.3O.sup.+ will be used interchangeably unless explicitly being described in comparative terms. For clarification, in the lexicon of ion exchange membranes please refer to the Glossary of Terms section of this application. As defined herein, it will be understood that protons, i.e. ionized hydrogen, represent a specific subset of cations, which in turn together with anions are a subset of all ions. It should also be mentioned that the ionized state of matter is not a stable condition. In nature ions spontaneously revert to stable elements over time, the very reason an unused battery self discharges.

[1201] One advantage of a hydrogen fuel cell compared to other forms of energy is its fuel comprises stable elemental hydrogen atoms without toxic compounds. In operation, the hydrogen atoms are stripped of their electrons at the time of use resulting in hydrogen ions H.sup.+, i.e. protons are created just-in-time to be used. To accelerate the ionization process the fuel cell employs a catalyst. A catalyst is substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change. Common hydrogen catalysts include platinum and palladium. As numerous embodiments of this invention, the composition of the catalyst layer may include additives and permanent fillers added to enhance catalytic turnover rates (TORs), reduce interfacial contact resistance, and to prevent poisoning of the CL. Once the hydrogen is ionized the resulting protons traverse the ion exchange membrane from the anode to the cathode.

[1202] Positive charge transport within the IEM occurs by two mechanismscharge hopping and vehicular transport, with conduction involving two physical forms of propulsion namely drift conduction in response to electrostatic forces, and diffusion, a statistical mechanical mechanism involving the random vibration of atoms. All four combinations occur in a conducting ion exchange membrane but in varying degrees, specifically charge hopping driven by diffusion, charge hopping electrostatically driven by drift conduction, vehicular transport of ions driven by diffusion, and vehicular transport of ions electrostatically driven by drift conduction.

[1203] The relative contribution of these four conduction components depends on the manufacture and composition of an ion exchange membrane, the influence of ambient conditions such as temperature and relative humidity, and the current density flowing across the membrane. In various embodiments of this invention, these relative contributions are decided by IEM design and processing by controlling the ionomer concentration within the polymer and by controlling the crystallinity and porosity of the polymer's molecular matrix.

[1204] In the vernacular of ion exchange membranes, charge hopping aka Grotthuss conduction is the mechanism where protons repeatedly jump to negatively-charged immobile ionized molecules called ionomers, hopping from one ionomer to the next. Since the ionomers in a PEM are negatively ionized immobile anions, only positive charged cations can traverse the matrix. The driving force of protonic charge hopping comprises both diffusion, current conduction resulting from a concentration gradient; and from electric drift, the electrostatic force experienced by charge responding to an electric field.

[1205] Charge hopping can occur in any atomic matrix containing ionomers, i.e. immobile ionized groups. In a PEM membrane, these ionomers comprise membrane-bound acids that ionize into immobile anions. Because protons can hop between the adjacent anions, hopping conduction does not require pores and channels in the atomic matrix for conduction to occur. As such, hopping conduction is one-dimensional with protons flowing in a relatively straight line from the anode to the cathode. The magnitude of hopping current depends primarily on the ionomeric density within the matrix.

[1206] The term vehicular transport by contrast describes the movement of ions through channels within the polymer matrix and does not rely on ions attaching and detaching themselves onto immobile ionomers within the polymer. The role of the acid groups in vehicular transport is thereby to donate protons into the matrix through ionization, not to carry current. In this regard ionic liquids can also contribute to vehicular transport but without increasing the immobile ionomeric density. In vehicular transport, free protons spontaneously attach themselves to water molecules to form hydronium ions. As hydronium ions are significantly larger than free protons, they require contiguous pores in the polymer's matrix to form conductive channels through which they move.

[1207] As such vehicular conduction is tortuous, involving significantly longer path lengths than hopping conduction. The longer path length means both the electric field and concentration gradient providing vehicular propulsion are reduced thereby reducing their relative contribution compared to charge hopping. At high current densities, water created in the oxygen reduction reaction (ORR) in the cathode catalyst layer (CCL) diffuses back into the matrix enhancing the role of vehicular transport by creating more hydronium charge carriers. In operation protons combine with water to form hydronium ions, some of which revert back into H.sup.+ and H.sub.2O, creating a equilibrium condition. By contrast the density of ionomers is fixed. At high current densities they become saturated and are unable to support greater currents.

[1208] In this complex manner charge hopping and vehicular transport both contribute to conduction in an ion exchange membrane. The relative contribution of diffusion and drift propulsion in each of these conduction mechanisms depends on the proton concentration gradient, membrane hydration, and the membrane's self generated electric field. In general terms, hopping conduction plays a dominant role at low currents while vehicular transport of hydronium dominates high current conduction.

[1209] In IEM lexicology, the term drift conduction describes current flow resulting from the electrostatic force exerted on a charge in an electric field. Drift conduction dominates charge flow in materials with an ample source of charge such as metal conductor or an ionomer carrying relatively low currents. The electric field present across the membrane is created autonomously by the accelerated ionization of hydrogen in the anode and the lack of protons persisting in the cathode together creating a perpetual charge imbalance so long that hydrogen continues to flow into the anode. While the electric field can also drive drift conduction of unbound protons in the matrix, their lifetime as free charge is limited by the presence of water interstitial to the polymer matrix.

[1210] In such cases, the hydrogen ions spontaneously bond to water forming charged hydronium ions. Like hydrogen ions, hydronium ions respond to electric fields exhibiting drift conduction. The major difference between charge hopping and vehicular transport is the conduction pathcharge hopping is a bulk property where conduction is able to flow directly through the polymer matrix. Because vehicular transport is limited to circuitous paths through the matrix, the net electric field is diminished significantly reducing the importance of drift conduction in vehicular transport.

[1211] The term diffusion describes the spatial reapportionment of molecules resulting from a concentration gradient. Rather than reacting to a force, diffusion is the statistical mechanical mechanism resulting from random motion whereby a concentrated bubble of ions has a greater chance of moving out of the congested region than it does heading back into the bubble. As such, both hydrogen ions and hydronium ions naturally diffuse from high concentration regions to lower concentration volumes. As long as hydrogen supply to the anode is maintained, the concentration gradient of protons ions will also persist, as such diffusion is present in charge hopping conduction. Maintaining a concentration gradient also drives diffusion based conduction via vehicular transport, especially at high currents.

[1212] Another key mechanism of fuel cell operation is the chemical reaction occurring in the cathode catalysts layer. In the cathode the incoming flux of protons and hydronium ions is countered by a preponderance of oxygen in the cathode. The oxygen combines with the protons by donating electrons, thereby reducing the cations back into uncharged hydrogen atoms. In steady state operation of a fuel cell, the rates of oxidation of hydrogen into cations in the anode and reduction of cations into hydrogen in the cathode necessarily balance in accordance with maintaining charge neutrality in the cell. Thermodynamics however dictates that the product of the coupled oxidation and reduction reactions, called a redox reaction, must have a lower energy than the fuel feeding the electrochemical cell. To satisfy this criteria, protons reduced to elemental hydrogen in the cathode necessarily combine with a reducing agent. Generally the reducing agent is either pure oxygen (100% O.sub.2) or room air which comprises 78% non-reactive nitrogen and 21% oxygen. Care must be taken to prevent carbon monoxide or H.sub.2O.sub.2 from reacting with the catalyst and poisoning the fuel cell.

PEM Fuel Cell Construction.

[1213] Given the emerging demand for clean and sustainable global energy applications, the need for reliable high-performance ion-exchange membranes for fuel cells is becoming increasingly evident, especially is the development of proton exchange membrane based fuel cells (PEMFCs). Unfortunately, present day PEM membranes suffer numerous deficiencies including excessive humidity dependence, low current density operation, low cell voltages, high membrane resistance and transient impedance, and an especially strong dependence of cell voltage on current. Other problems include repeated swelling and shrinkage of the membrane with water retention within the polymer leading to polymer wear out and shortened use life.

[1214] Together, these factors, further exacerbated by self-heating, humidity and ambient temperature dependence limit the conversion efficiency and electrical power density of even state-of-the art fuel cells. In particular, fuel cell voltage sag and/or voltage collapse with increasing current is especially problematic as it limits the fuel cell from directly driving a high current battery or the low-impedance input of a switching power supply needed for DC/DC voltage conversion. These problems arise for a variety of reasons including bad fuel cell design, poorly constructed membranes, inadequate process control of membrane fabrication, and lack of scalable manufacturing processes. Other factors include poor gas delivery as limited by fundamental construction deficiencies in gas diffusion layers and high interfacial contact resistances.

[1215] As described previously, a single proton-exchange membrane fuel cell generally comprises a five-layer membrane electrode assembly MEA5 sandwiched by bipolar plates BPP. The BPP is a rigid support structure in the PEMFC stack within which reactant and coolant flow occurs. The BPP is also responsible for current conduction and heat dissipation. The MEA5 comprises a gas diffusion layer (GDL) with a microporous layer (MPL) surrounding a three-layer membrane assembly or MEA3. The GDL is a layer of carbon paper or carbon cloth, which plays multiple important roles in gas distribution, mechanical support and electrical connection. Carbon layers are formed upon a substrate of carbon black and polytetrafluoroethylene (PTFE) referred to as MPL, which assists in the timely removal of electrochemically produced water. As an embodiment of this invention, these carbon layers are heterogenous of varying concentration and porosity.

[1216] The MEA3 also known as a catalyst coated membrane or CCM comprises two catalyst layers (CLs) surrounding a proton-exchange membrane (PEM). The CL is the site where the hydrogen oxidation and oxygen reduction electrochemical reactions occur, through a series of coupled physiochemical processes. Platinum-loaded carbon, which is finely dispersed to interact with the ionomer, is the most frequently used catalyst owing to its excellent activity and durability in an electrochemical environment. Aside from platinum (Pt) other platinum group metals (PGMs) include palladium (Pd), osmium (Os), rhodium (Rh), ruthenium (Ru), and iridium (Ir). PGMs are desirable for their excellent electrical conductivity and catalytic activity and for their resistance to corrosion in acidic environments consistent with proton based charge transport. Unfortunately many noble metals are notoriously expensive. Alternative catalysts made in accordance with this invention are described in a subsequent section of this application.

[1217] One especially troublesome deficiency of ion exchange membranes is their loss in structural integrity, strength, durability and rigidity as the active ionomer is thinned. While attempts have been made to integrate reinforcement throughout the membrane's active film, any increase in ionomer strength is countered by a decrease in ion conduction and lower film conductivity, reducing power efficiency and increasing membrane resistivity thereby offsetting the linear reduction in resistance gained by thinning the membrane. Lower efficiency also further exacerbates membrane heating,

[1218] One approach is to integrate PTFE into a PFSA perfluorosulfonic acid membrane to form a heterogenous reinforced composite membrane or CRM. While simple to conceptualize, hydrophilic PFSA is mutually incompatible with the highly hydrophobic nature of PTFE. The intrinsic incompatibility of hydrophilic ionomers such as PFSA coated onto a hydrophobic PTFE substrate causes film stress. These stresses are aggravated by changes in both membrane hydration and temperature during normal operation. Specifically water logging and swelling causing severe volumetric changes in the PFSA are a function of both current and relative humidity.

[1219] Elevated temperatures and temperature gradients arising from the fuel cell's exothermic reactions likewise cause stress arising from the heterogenous films exhibiting differing temperature coefficients of expansion, i.e. differential CTEs. In normal use, power levels invariably fluctuate, in turn causing repeated expansion and shrinkage in the film under wet-to-dry-to wet transitions. As such, humidity cycling, temperature cycling, and power cycling all aggravate interfacial imperfections in the composite ionomer causing creep deformation, delamination, and cracking. In particular, the formation of cracks, tears, voids, and delamination dominantly occur between the PTFE and PFSA layers, leading to an irreversible deterioration of the fuel cell performance.

[1220] Rather than relying on CRM strengthening the ionomer itself, in an embodiment of this invention the ionomer is reinforced laterally by a matrix of semi-rigid pillars to form a skeleton interspersed throughout the membrane, thereby providing structural support to the IEM. Skeletal support is not mutually exclusive from the heterogenous reinforced composite membrane, but can reduce the mole fraction of inert PTFE in the film improving IEM conductivity or eliminate it totally.

IEM Structural Support.

[1221] The biggest problem of a fuel cell is sagging and deformation of the active ionomeric film during manufacturing and in operation. This problem originates from the intrinsic relationship between the electrical conductivity and membrane thickness. As shown in FIG. 15A, the electrical resistivity 210 depends of the thickness of an ionomerthe thinner the film the better the conductance and the lower its electrical resistance.

[1222] Unfortunately, thinner films exhibit reduced mechanical strength and durability, causing them to sag and deform easily during handling and manufacturing. This increases the risk of damage during fabrication, manufacturing, and assembly of fuel cell or electrolysis modules. The term sag is defined as the deformation distance below the plane defined by the membrane's attachment points to its mechanical support. Ideally a membrane should be perfectly flat, coplanar with its edge support. Any deviation below the attachment plane is undesirable as it renders bonding between the gas diffusion layer and the membrane less uniform, potentially creating air gap pockets with no electrical contact, thereby increasing resistance.

[1223] The film sagging problem is further exacerbated in larger area membranes where mechanical edge support from the module assembly is farther removed from the center of the membrane and therefore less able to maintain film rigidity. As depicted in FIG. 15B cross sectionally representing the vertical displacement of a membrane, the center of a membrane sags below the horizontal plane of the membrane, with the greatest displacement in the center farther from any mechanical support.

[1224] For example, membrane 211 illustrates the characteristic sag of a narrow width 150-m thick film. Despite reducing the membrane's mass, thinning membrane 212 to a 40-m thickness decreases film rigidity thereby increasing the extent of the sag. Widening the distance across an IEM in order to achieve a larger area for greater current conduction further decreases mechanical support and further increases the magnitude of membrane sag as evidenced by 150-m thick membrane 213 and even more so for 40-m thick membrane 214. In other words every design and process change designed to enhance conductivity and reduce fuel cell resistance renders the ion exchange membrane less rigid and more subject to damage. The combined use of a thin large area membrane further exacerbates the film sagging problem, potentially rendering the membrane unmanufacturable.

[1225] Further complicating matters, most ionomeric membranes are made electrically active by conductive acid groups attached onto the main polymeric chain using an organic sidechain as an intermediary, i.e. as a pendant connecting the ionomer such as sulfonic acid to the backbone. While this approach provides additional control in trading off strength versus conductivity, it is inadequate to solve the mechanical rigidity issue during manufacturing.

[1226] Even worse, ion exchange membranes assembled into fuel cells can swell with water absorption during operation. The swelling occurs both laterally along the plane of the membrane and orthogonally to the membrane's surface impeding current and adversely affecting electrical conductivity. Swelling is a function of current, relative humidity, and temperature. Repeated cycles of swelling, e.g. from humidity cycling, also invokes various wear-out mechanisms shortening film integrity, reliability, and the use life of the membrane.

[1227] To resolve this problematic tradeoff between membrane conductivity and mechanical film strength, a new ion exchange membrane support structure is disclosed herein as an inventive embodiment comprising a skeletal support structure of electrically inactive pillars such as PTFE interspersed throughout the film at regular periodic intervals. When arranged in a waffle-like pattern, the skeleton is able to support thin membranes of arbitrary thickness unrelated to mechanical rigidity within the membrane's active polymer matrix. In one embodiment, this mechanical support or endoskeleton comprises semi-rigid pillars to which thin or fragile membrane can adhere. These pillars provide mechanical support to prevent film sag by holding the membranes tight, and in so doing reduce the range of atomic displacement with hydration.

[1228] This principle for mechanical support is illustrated in FIG. 16 where the skeletal pillars of a single IEM are shown graphically in cross section. As depicted, these inert pillars surround the membrane's periphery and transection the film at regular intervals, generally evenly spaced. The pillars on the periphery 220a and 220b referred to as the membrane's exoskeleton are wider as the they are designed to be sufficiently wide to separate, i.e. singulate, each individual membrane from other IEMs fabricated in the same membrane-frame using a cutting mechanical or optical technique. The other pillars, referred to as an endoskeleton, may be constructed more narrow than the exoskeletal pillars as they are not intended to be cut. The exoskeletal and endoskeletal pillars are connected together to form a three-dimensional grid-like structure not visible in this two dimensional cross section.

[1229] Singulation may be performed by cutting the exoskeleton down its middle perpendicular to the film's surface using a laser, saw blade, or less ideally using a sharp edged mechanical punch. Laser singulation is preferred as it produces less mechanical stress on the film reducing the risk of tears, breaks, or damage to the membrane. The internal pillars 221, 222a, and 222b referred to herein as an endoskeleton, are as graphically represented narrower than that of the exoskeleton pillars 220a and 200b as they do not require cutting. After singulation, the endoskeletal grid remains a permanent artifact within the final IEM for use in a fuel cell, electrolysis unit, or filter application.

[1230] Referring to the graph curves 215, 216a, 216b, and 217a-217d illustrate the shape of the membrane for various support arrangements. Although the curves schematically represent in exaggerated form the shape of the membrane segments using various skeletal patterns, the abscissa of the graph also numerically represents vertical displacement or sag, with the peak displacement located laterally at the center between its two adjacent pillars. In membrane profile 215 exhibiting the greatest degree of sag, a membrane is supported only by exoskeletal pillars 220a and 200b. Adding a center endoskeletal pillar 221 bifurcates the film into two pieces 216a and 216b greatly reducing the sag. The benefit is made further evident by further subdividing the membrane into quartiles using endoskeletal pillars 222a, 221, and 222b positioned uniformly at 25%, 50% and 75% of the membranes width. The resulting reduction in film sag is represented by curves 217a, 217b, 217c, and 217d.

[1231] While the graph illustrates the addition of endoskeletal pillars in one dimension, the method can be applied in both axis, i.e. along the width and length of the membrane. Ideally, the spacing of the pillars long the x-axis and y-axis are substantially the same, forming a square frame to hold the active membrane. The square grid principle can be followed even when fabricating a rectangular shaped membrane simply by using integer number of squares to form the IEM. For example the width might comprise three endoskeletal pillars forming five segmented areas while lengthwise the distance may divided by 23 endoskeletal pillars forming 25 segments, five times the width. The net resulting shape is 525=125 squares with a net IEM aspect ratio of 5:1. Although the exoskeleton requires a minimal width to support singulation, there is no such restriction for the endoskeletal pillars which may be the same width as the exoskeleton or smaller, including the possibility of more than one endoskeletal width.

[1232] The benefit of the endoskeleton is not limited to manufacturing, it also aids in maintaining film integrity during operation. Specifically, ion exchange membranes physically deform during operation. The deformation can occur from local heating or retaining water, a mechanism referred to as membrane swelling. Humidity, temperature, and IEM current density all affect swelling. As depicted in FIG. 17, membrane swelling is greatly reduced by the use of an endoskeleton. Specially, in an unsupported membrane 230, the polymer molecules depicted as atoms 231 undergo expansive forces in all directions including in-plane forces 232x and force normal to the membrane surface 232y. Moreover these forces may not be uniform and local variations in temperature, humidity, current conduction, and film stoichiometry all affect expansive deformation. The result is an unpredictable change in volume 234. Deformation puts stress on the catalyst layer which can lead to cracking and permanent damage. Swelling can also reduce membrane conductivity further increasing heating. At a molecular level, repeated stretching comprising cycles of expansion and contraction can damage the membrane itself causing tears, gas leakage, and electrical shorts shunting electrical generation altogether. Other electrical mechanisms such piezoelectric effects can also impact the cell's electrostatic potential lowering the net voltage of the fuel cell stack.

[1233] By adding endoskeletal pillars 235a and 235b to IEM membrane 230 as support, in-plane forces causing expansion are countered in kind by opposing forces 236x exerted from the skeletal pillars thereby preventing displacement. Although the fuel cell polymeric matrix may be under pressure, essentially there is no where for the atoms in the polymer to move to except orthogonally in response to force 236y. Even so because of the molecular bonds between the polymeric IEM 230 and the endoskeletal pillars 235a and 235b, there is limited opportunity for displacement because the film surface is tethered on both ends. The resulting magnitude in displacement in the y-direction 237 is very limited even though there is no direct opposing force in perpendicular axis.

[1234] Formation of the exoskeleton and endoskeleton and design considerations for fuel cell applications are further elaborated in a related application Advanced Fuel CellDesign, Apparatus, & Fabrication, referenced herein. In general the pillars of the membrane skeletal are formed by a polymeric compound such as a plastic such as a thermoplastic or polyolefin, PTFE, or glassy matrices reinforced by a filler such as carbon fibers, graphite, graphene, carbon nanotubes, and other mechanically strong insulating materials. In one implementation used to form the support pillars, finely powdered PTFE grains along with strengtheners are loaded into the mold and compressed to a high pressure between 10-to-100 MPa then heated to 360 C. to 380 C. to sinter the powder into a single polymerized mass. The addition of carbon fiber, graphene, carbon nanotubes, or polymeric shards provides added mechanical strength and support. In another embodiment the filler may include nanospun fibers of plastics or PTFE.

[1235] As described, the pillars are quasi-rigid, nonporous to gasses, not electrically conductive, and relatively inert chemically. One key design consideration is the active ionomer film filling the spaces between the pillars must adhere to the skeleton. The simplest way to ensure good attachment is to employ, at least in part, the same material in the pillars as those comprising the membrane. For example, forming the endoskeleton from PTFE with carbon filler and forming the membrane from PFSA coated PTFE means the membrane and the pillar are guaranteed to remain compatible because they both contain PTFE. Using a pure PFSA polymer as the membrane is more complex as the hydrophilic membrane must grafted onto hydrophobic PTFE skeleton using chemical reagents referred to herein as a pillar link to bridge the two. Another option is to use a low mole fraction of PTFE mixed with PFSA as a powder of nanospheres in the membrane starting materials for dispersion casting. Other options include choosing a polymer with a more reactive surface to facilitate enhanced bonding.

Membrane Matrix Frame.

[1236] Although the disclosed skeletal support structure strengthens the IEM membrane for operation and prevents mechanical damage to the film, by itself the endoskeleton and even the exoskeletal pillars do not facilitate convenient handling of the IEM during molding, post mold chemical treatments, catalyst formation, and attachment to the GDLs. In the referenced patent, one method to handle the thin film is to use temporary handles. A handle is a rigid block of material attached to one side of the membrane to facilitate handling needed to move the film from one processing step to the next without actually gripping the membrane. Although the use of handles including plastics, silicon wafers, metal, or polymers cand be used to transport the membrane among its processing steps, a handle suffers several limitations.

[1237] First the process of attaching a handle and then later detaching involves extra processing steps. Secondly, during chemical treatments portions of membrane attached to the handle are not exposed to the chemical reagents. This issue requires the assembly to be flipped over to treat both sides. Lastly, the attachment between the handle and the membrane can leave contaminant on the membranes surface. As such, it is better to coat both sides of the membrane with the catalyst layer before attaching any handle. But this requirement is paradoxical as there is no means to transport and coat the membrane without first attaching a handle.

[1238] To resolve this persistent and extremely problematic handling issue in IEM fabrication, one embodiment of this invention is a membrane matrix. The membrane matrix comprises multiple ion exchange membranes fabricated concurrently, together circumscribed by a membrane matrix frame. The membrane matrix frame provides mechanical support for the array of membranes during fabrication. As shown in FIG. 18A, membrane matrix frame 250 includes a mechanically rigid material such as a carbon reinforced polymer surrounding membrane matrix 251x, the details of which are not shown. Membrane matrix frame 250 is secured to the membrane matrix 251x through regularly positioned tie bars 252. The circumscribing matrix frame 250, which is significantly stronger than the membrane matrix 251x it holds, provides mechanical rigidity of sufficient strength for mechanical or robotic handlers to firmly grab ahold of the matrix without damaging or bending the array contained within. Membrane matrix 251x is subdivided by inter-matrix exoskeleton 254z enabling greater mechanical strength during manufacturing and providing a means to manufacture multiple membranes in a single polymer sheet and subdivide them later, a procedure referred to by the semiconductor industry as batch processing. Batch manufacturing reduces production costs, improves quality, and makes products more uniform and better matched.

[1239] In one embodiment of this invention a marker or identifier 249 is included on one side of the frame to distinguish anode from cathode. The identifying mark may comprise an ink, fluorescent ink, indentation, etched, or stamped region identifiable using visible light, infrared, UV, or X-ray inspection. The marker which should be visible through a catalyst layer (CL) need not be visible through an attached GDL, since the MEA5 assembly process sequence can identify the anode from cathode and for example attach the CDL first meaning the last GDL to be attached identifies the anode side. With X-ray inspection, the GDL will not interfere with the inspection process.

[1240] Depicted in FIG. 18B, tie bars 252 connect outer matrix frame 250 to a wider more rigid periphery of membrane matrix 251 comprising exoskeletal border 254w circumscribing the membrane matrix area 251x. Membrane matrix area 251x in turn includes an array of multiple IEMs parsed by the skeletal matrix exemplified by a sample portion of endoskeleton 253x. In addition to endoskeletal support, the membrane matrix area 251x may also include exoskeletons 254z allowing one polymer sheet to produce multiple well matched IEMs.

[1241] During singulation only a portion 254x of the width of original exoskeleton 254w border survives the fabrication sequence as shown in FIG. 18C. As shown, 254A exoskeletal pillars 254a through 254e subdivide membrane 251x into multiple IEMs comprising IEM-1 251a, IEM-2 251b, IEM-3 251c, IEM-4 251d, IEM-5 251ae, and IEM-6 251f. The final multi-IEM membrane maintains structural support from its internal skeletal components despite the fact that none of the features of tie bars 252 or membrane matrix frame 250 survive. Pragmatically the thickness of the membrane handle is thicker than the membrane, a minimum requirement needed for compatibility with mechanical and robotic handlers.

[1242] The overall process to form a MEA5 (i.e. CCM) with a matrix frame is depicted in the flow chart shown in FIG. 19A starting with step 255 Fabricate Skeleton and Matrix Frame. After that two choices exist for chemically forming the ionomer membrane. In step 256a Form Bulk Conduction IEM a semi-homogenous material is deposited, grown, or casted in the presence of the previously fabricated rigid skeleton and matrix frame. In the case of a PEM membrane, such a material may comprise a ionomeric polymer such as perfluorinated sulfonic acid, aka PFSA, formed as a semi-uniform film, or possibly intermixed with PTFE. Alternate membranes may comprise hydrocarbons functionalized by immobile acid groups such as sulfonic or phosphonic acids. Fillers may include both permanent fillers as well as a sacrificial filler. The material may be dispersion casted in a mold from powdered ionomer material or molded from a solution comprising a suspension of the ionomeric monomer in a solvent such as PFSA or hydrocarbon compounds.

[1243] Alternatively in step 256b Form Surface Conduction IEM, the fabrication may involve sequential steps of forming a non-electrically active polymeric backbone such as PFTE powder co-activated by grafting electrically active ionomer sidechains and pendants such as PFSA onto the mechanical support framework. The actual membrane chemistry and process steps thereof varies by material and by the conducting ionic species, e.g. protons H.sup.+ in a cation exchange membrane also referred to as a proton exchange membrane (PEM), or by anions such as OH in an anion exchange membrane (AEM). More details of the membrane formation are discussed later in this application.

[1244] Subsequent to polymerization the process proceeds with the step Remove Sac Filler, Anneal, Cure, Dry 258 where the polymer is annealed, cured, and dried. In the event that the membrane includes a sacrificial filler, the filler is removed by a solvent prior to drying.

[1245] Alternatively, the membrane may be soaked in an ionic liquid in step 257a prior to curing. An ionic liquid comprises an organic salt that melts into a liquid state at room temperature releasing mobile cations and anions into a ionomeric polymer membrane. Because ionomeric membranes exhibit high specificity to only one polarity of ion transport, specifically hydrogen and hydronium cation transport in proton exchange membranes (PEM) or hydroxide anion transport in anion exchange membranes (AEMs), doping a IEM with an ionic liquid primarily enhances conduction in the dominant ionic species n the IEM. For example an IL introduced into phosphonic or sulphonic PEM membrane will enhance proton conductivity without increasing the number of ionized acid groups functioning as immobile anionic ionomers.

[1246] After polymer formation, membrane fabrication may proceed directly to catalyst layer formation shown by step 260. Alternatively in step 259a, the surface may be sprayed prior to CL formation with a nanocoating to enhance catalysis, reduce interfacial contact resistance, selectively suppress gas diffusion of fuels or toxins such as NO or H.sub.2O.sub.2, to suppress leakage of ionic liquids, or otherwise improve efficiency and/or enhance reliability. The coating may be sprayed subsequent to ionomer polymerization and prior to catalyst layer deposition, or subsequent to CL formation but prior to GDL attachments. The stochiometric contents of the nanocoating are discussed later in this application.

[1247] In step 260 Form Catalyst Layers the membrane is coated on both sides by a catalyst layer typically comprising carbon slurry mixed with a rare earth metal such as platinum (Pt), a metal oxide such as titanium dioxide (TiO.sub.2), or a combination thereof. Other additives may include MOFs, POSS, or nanoparticles including functionalized nanotubes, graphene oxides, and nanoclusters. The specific catalysts used in the CL depend on the type of ion exchange membrane, either PEM or AEM, and may vary from the anode to cathode side of the CCM. The catalyst layer may be deposited using chemical vapor deposition, by printing, ultrasonic spray painting, or sputtering. Because the catalyst comprises a mix of various elements and compounds of varying liquid solubility and vapor pressure, CVD or printing methods are subject to variability in mass production.

[1248] In contrast, sputtering uses a non-thermal non-chemical process involving a mass transfer mechanism is better suited to deposit films of precise and identical stoichiometry to its source target. Sputtering is also capable of performing an in-situ pre-deposition sputter etch process to activate the membrane's surface ions, ameliorate unwanted surface states, and remove surface contaminants, thereby improving the electrochemical interaction between the catalyst and the IEM.

[1249] An alternative embodiment of catalyst layer formation adapted to this invention is to print or extrude a thin catalyst layer decal as a laminate to mechanically attach to each side of the membrane. Such laminate processes are subject to interfacial states, contaminant adhering to the IEM surface, and to air pockets, aka bubbles, unavoidably forming between the soft membrane and the CL decal during the lamination process. Special cleaning steps and squeegee steps such as Dr Blade processes are required as part of the lamination process sequence.

[1250] More details of the catalyst layer formation are subsequently discussed later in this application. Regardless of what method is used, however, the catalyst material must be applied to both opposing sides of the membrane, meaning the membrane must be turned over to expose the anode and cathode CL formation sequentially. After the catalyst layer is deposited the resulting sandwich is referred to as a MEA3 meaning a three layer membrane electrode assembly or CCM, an acronym meaning a cathode coated membrane.

[1251] Subsequent to catalyst layer formation, the membrane may be optionally soaked in an ionic liquid 257b, coated with a nanolayer 259b, or both. The resulting structure represents a completed three layer membrane electrode assembly MEA3 261 ready for attachment to gas diffusion layers. Although the described processes can be varied in alternate sequences, to protect the catalyst layer from ambient toxins the nanocoating process step 285b necessarily must follow CL formation 260. The same protection is not likely required on the anode side as the hydrogen source is generally ultrapure with no gaseous contaminants.

[1252] Alternatively, to enhance interfacial charge transport, the nanocoating formation 259a must precede CL formation step 260. Similarly ionic liquid s may be introduced into the membrane prior to CL formation in step 257a or thereafter in step 257b. Regardless of the sequence, one advantage of performing nanocoating process step 259b after ionic liquid doping is to seal the I.sub.L within the membrane to prevent leakage. The unique process sequence made in accordance with this invention results in a completed MEA3 assembly 261.

[1253] As an embodiment of the membrane electrode assembly fabrication illustrated in FIG. 19B, two options exist to convert a MEA3 catalyst coated membrane into a into a MEA5 five-layer membrane electrode assembly. The steps involve first fabricating heterogenous gas diffusion layers (hGDLs) in step Fabricate Heterogenous hGDL 262 using printing or deposition of carbon fibers onto carbon fiber paper referred to as a microporous layer (MPL).

[1254] In an embodiment either the starting MPL or the carbon ink used to form the printed carbon layer may be embedded with GDL fillers. The GDL filler may comprise metallic or scavenger nanoparticles added principally to bond to, extract, and degrade nitric oxide (NO) and other airborne contaminants from being transported to the catalyst layer (CL) and thereby damaging or disabling the catalyst ions. In a hydrogen fuel cell the protective GDL filler nanoparticles are required primarily in the cathode GDL expose to air. In a direct methanol fuel cell however, contaminants may also be carried by an impure methanol source.

[1255] The lower case prefix h is the acronym hGDL identifies the gas diffusion layer is heterogonous, not uniform in composition or atomic density where the deposited carbon layers may comprise stepped or graded coatings generally increasing in porosity monotonically. In one set of embodiments, the deposited layers included shorter higher density fibers adjacent to the MPL and more porous materials comprising longer carbon fibers subsequently deposited atop the higher density layers. In one embodiment, the gradations in carbon density vary in discrete steps while in other implementations the variations are more gradual.

[1256] Subsequent to the hGDL formation in the step entitled Coat hGDL 263, the MPL layer may be treated with a thin coating to improving mechanical attachment and electrical continuity between the MPL and the CCM's catalyst layers by reducing interfacial states, enhancing conductivity, and reducing interfacial stresses. MEA5 fabrication comprises two options, either to (i) attach the GDL gas diffusion layers to the MEA3 in step 266 then to singulate the IEM into separate pieces in step 284a, or (ii) to first separate the film into distinct components, i.e. to Singulate IEMs from Matrix Frame in step 264a then attach the GDL to each membrane piece individually in step 265.

[1257] Specifically in the sequence comprising step 264 Singulate IEMs from Matrix Frame 264a followed by step 265 Attach GDL to Each IEM the assembly method comprises separating the multi-IEM matrix into precut pieces before attaching similarly sized GDL layer. Such arduous assembly method involve more handling and therefore risk film damage. The alternate flow involving step 2666 Attach GDLs to Matrix followed by step 264b Singulate IEMs from Matrix Frame is a batch process postponing the singulation of the membranes into discrete IEMs to the last possible step. Regardless of the flow used, the final outcome is a discrete 5-layer membrane electrode assembly (MEA5) 266 ready for assembly into a module, either as fuel cell, an electrolysis unit, or as ion specific filter.

[1258] Using dispersion casting in a pressurized mold, ionomers can be formed into a matrix of thin ion exchange membranes and skeletons supported by a stiff thick matrix frame surrounding the array. In this manner, two different designs are possible as shown in FIG. 20frame matrix 300 where the membrane 305 is offset vertically from the center of the frame 302, and frame matrix 330 where the membrane 335 is centered vertically at the center of the frame 332. As shown for matrix 300, the thin membrane 305 comprising five IEMs 301a-to-301e including exoskeletal pillars 304a, 304b, 304c is vertically offset from the center of the matrix frame 302 grasped by clamp 303. While simpler to fabricate than symmetric frame matrix 333, the asymmetric structure necessarily applies torque to membrane 305 from vertically offset clamps 303. In contrast, for matrix 330, the thin membrane 335 comprising five IEMs 331a-to-331e including exoskeletal pillars 334a, 334b, 334c, is vertically centered to matrix frame 332 grasped by clamp 333 and therefore does not experience torque or twisting forces.

[1259] In one method the matrix frame, exoskeleton, and endoskeleton and concurrently molded using dispersion casting as shown FIG. 21 where a mold chamber comprising a sidewall 350a bottom portion 350b create a chamber which is reduced in volume by an insert referred to here as a mold chase 373 to produce several different open chambers of varying depth and width. In the example shown, the mold chase defines three different geometries of varying depth and width for loading monomer mold compounds into. Although the mold chase shown forms three different geometries having two different depths and three different widths, more regions of varying width and depth may also be employed. The mold chase 373, generally comprising stainless steel may be precision etched, cut, or milled to any dimensions. Mold costs depend on the mold and molding equipmenta larger mold chamber requires more steel and larger more expensive molding machines. Unlike injection molding, casting molds do not require the same precision tooling to prevent leakage.

[1260] In the example shown the mold defines at least one deep trench-like region 352a for the matrix frame, a second wider but shallower trench-like region 354a defining an exoskeleton and a third narrower shallow trench-like region 355a defining an endoskeleton. The various trenches are part of a three dimensional grid pattern that merge into another trench oriented perpendicular to the ones shown. The trenches are then filled to the top with a polymer mold compound such as a plastic or PTFE powder or a solution, then polymerized under heat and optionally light pressure, merging the monomers into a single piece of polymerized PTFE including regions 352b, 354b, and 356b which can be removed from the mold once it cools or partially cures.

[1261] In another embodiment, shown in FIG. 22 the mold trenches 352c, 354c, and 356c are loaded with a heterogenous mix of a polymer such as PTFE and a some filler for increasing mechanical strength such carbon fiber, graphene, carbon nanotubes, plastic shards, or other materials. Heating under pressure causes the monomers in the dispersion or solution to polymerize with the fibrous filler, ultimately becoming permanently locked within the polymer's matrix as illustrated by matrix frame and skeletal features 352d, 354d, and 356d.

[1262] Subsequent processing of the skeleton fills in the intervening areas withing the skeletal grid with an ionomer or more accurately an ionomeric polymer. As shown in FIG. 23, the ionomer may comprise a bulk conducting IEM 400b such as polymerized PFSA, or a surface conducting IEM such as PFSA coated PTFE. The membrane matrix is then subsequently coated by anode catalyst layer (ACL) 401a and cathode catalyst layer (CCL) 401c to form the CCM sandwich as shown. The resulting membrane matrix shown in the exemplary top view of FIG. 24 includes a multiplicity of separate IEMs bounded by exoskeletons 356b and containing ionomer 355 and endoskeletal support 354.

[1263] The entire structure is held together by a thicker wider supporting membrane matrix frame connected to the outer exoskeleton 356a by tie bars 353. After singulation where the membrane matrix frame is cut into pieces by laser, saw, or stamp, a completed IEM 360 a fraction of the size of the matrix results. FIG. 25 illustrates two horizontal cuts 357a and 358b and two vertical cuts 358a and 358b remove the completed matrices from the matrix frame while FIG. 26 illustrates cutting along the exoskeleton with exemplary cut lines 359a and 359b singulate the matrix into discrete IEMs.

[1264] Although the example shown illustrates a single 51 row of IEMs, the membrane matrix may include multiple rows such as a 52 grid by introducing additional horizontal exoskeletons similar to exoskeleton supports 307a and 307b into the patter. The shapes of the IEMs may be square or rectangular with aspect ratios typically of 5:1 or 7:1 and generally not exceeding 20:1. For example a 630 aspect ratio produces as active area of nearly 180 cm.sup.2 neglecting are lost to the endoskeleton. At a current density of 200 mA/cm.sup.2 this active area corresponds to a conduction current of 36 A and at of 500 mA/cm.sup.2 results in a current of 90 A.

[1265] As described previously the relationship between the matrix frame and the membrane may be symmetric or asymmetric. The asymmetric design for concurrently fabricating IEM1 through IEM5 membranes 301a-to-301e shown in FIG. 27 include matrix frame 302 and clamp 303 not vertically centered on ionomer membrane 305. Although this cross section appears to lack structural rigidity along the width of the membrane from frame to frame, top view of IEM2 reveals exoskeletal support laterally via 307a and 307b not shown in the cross section. If added support is required to prevent sagging, additional exoskeletal rails can be added, rails that are not cut during singulation but remain in the final IEM.

[1266] FIG. 28 illustrates a close up of IEM1, the membrane closest to the matric frame 302. Note that although the outer exoskeleton 304a could be merged into matrix frame 302 because they are different in thickness, it is advantageous to insert as space 305x shown in the regular cross section to in the provide some degree of flexing to prevent breakage. At regular intervals add support to the frame is provided by tie bars 304x merging exoskeleton 304a to matrix frame 302. One possible fabrication process to form an IEM with an asymmetric membrane frame is shown sequentially starting at FIG. 29 with mold chamber 363 having a bottom portion 350b and a side portion 350a.

[1267] In FIG. 30 a mold chase 373 is inserted reducing the volume of chamber 363 to defined regions to insert polymer for the skeletal and frame support of the matrix. These trenches identified by the element they form include frame region 370, exoskeleton regions 371a and 371b, and endoskeleton regions 372a, 372b and other regions not labelled. In FIG. 31 mold chase 373 is loaded with the mold compound and any filler to frame region 380, exoskeleton regions 381a and 381b, and endoskeleton regions 382a, 382b and other regions not labelled. In FIG. 32, the compound is polymerized forming the membrane matrix including frame region 390, exoskeleton regions 391a and 391b, and endoskeleton regions 392a, 392b and other regions not labelled.

[1268] The polymerized matrix is then removed from the mold chase, the mold chase is removed from the mold chamber and the completed frame and skeleton is flipped over withing the chamber comprising frame feature 390, exoskeleton features 401a and 401b, and endoskeleton features 402a, 402b and other regions not labelled as shown in FIG. 33. The ionomeric compound 410 is then loaded into the mold as shown in FIG. 34, followed by lightly pressurized force with mold cap 411 in FIG. 35. The purpose of mold cap 411 is not to apply high pressure but to hold the mold compound, solvents, and cross linkers in place during polymerization. The monomeric contents are then cross linked into a polymer as shown in FIG. 36 including any heating treatment to accelerate cutting or drying.

[1269] During the polymerization process shown in FIG. 37 the ionomer volume may shrink slightly whereby the exoskeleton pillars 401a, 402a and endoskeleton pillars 402a and 402b may extend slightly above polymerized ionomer 410. The expansion or contraction of a polymer during polymerization depends on the specific chemistry of the polymer. The matrix frame is then removed from the mold and optionally treated using post molding chemical processes including additional curing, rinsing, drying, soaking, or coating. Subsequent to polymerization but before forming the catalyst layers, an ionomeric film made in accordance with this invention may be (i) soaked in ionic liquid to dope the membrane for higher conductivity; (ii) nanocoated to enhance interfacial properties; or (iii) both. In the third case, the nanocoating may also be utilized to prevent leakage of I.sub.L from the membrane. In some instances nanocoating materials such as PTFE nanospheres or dopamine (DPA) may be integrated into the catalyst layer rather than being applied separately. It should be noted that while depositing a nanocoating prior to CL deposition, i.e. forming a nanocoated interfacial layer between the membrane and the catalyst layer can also intercept poisons such as H.sub.2O.sub.2 from diffusing into the membrane and damaging the ionomeric groups, it cannot protect the catalyst layer from environmental contaminants as it is located beneath the CL, not between the CL and GDL.

[1270] FIG. 38 illustrates the matrix frame is then placed flat side down onto vacuum chuck 412 for sputter deposition 413a of the catalyst layer, e.g. to form the IEM anode. The illustration shows no added support to the matrix, but optionally a handle or protective coating can be attached to the flat side prior to this step. After CL coating shown in FIG. 39 the catalyst is present in flat regions 415a, atop the skeletal pillars 415b, along the interior edge of the frame 415c, and atop the frame 415d. Only regions 415a atop the ionomer 402a are electrically active. For cathode CL coating the entire assembly must be flipped upside down. Because of the tall frame it cannot be placed directly on the sputtering chuck unless until handle support 421 is first attached as shown in FIG. 40.

[1271] The handle can be any thick protective coating, or comprise a metal, silicon, or polymer slug designed to match the size of the matrix frame. Because of the possible slight height difference between the pillars 401, 402a and 402b compared to ionomer 410, the handle 411 may not uniformly contact catalyst layer 415, but instead include a small gap 412. In actual use, assembly pressure within a fuel cell state eliminates the gap, but preferably membrane synthesis conditions can be optimized to minimize or eliminate the gap.

[1272] In FIG. 41 the entire assembly is flipped upside down so that catalyst 453c deposition can be performed. As described previously, a nanocoating formed subsequent to membrane polymerization and prior to GDL attachment may either immediately precede catalyst formation; may follow CL formation, or alternatively may be integrated into the catalyst layer during its formation.

[1273] Because handle 421 is thicker than matrix frame 390c, the frame will interfere with thermal conduction from heat chuck 420 into the deposition surface. The problem is remedied by inclusion of a thermally conductive handle 421 smaller the membrane matrix. Handle 421 may comprise metals such as copper or steel or may comprise silicon wafers. FIG. 42 shows the film immediately after the cathode catalyst layer 430 has been deposited while still attached to handle 421 and vacuum chuck 420.

[1274] FIG. 43 illustrates the completed CCM still connected to the matrix frame. For the sake of clarity, the handle 421 has been removed from the illustration, identified as vacant region 431. Before attaching gas diffusion layers (GDLs) but subsequent to CL formation, an ionomeric film made in accordance with this invention may be soaked in ionic liquid (IL) to dope the membrane for higher conductivity. A nanocoating deposited atop the catalyst layer which may included carbon and other conductive components such as graphene, functionalized nanotubes, metal-organic-frameworks (MOFs), transition metal oxides, zirconium and tungsten compounds, and other permanent fillers discussed later in this application, may be included to reduce interfacial resistance between carbon in the GDL and the catalyst layer.

[1275] In FIG. 44, gas diffusion layer GDL 432 is attached to the cathode. During the cathode GDL attachment process as shown the GDL is attached to the entire membrane matrix area containing multiple IEMs contained with the same frame. Thereafter in FIG. 45 the handle is removed. In FIG. 46 the anode gas diffusion layer GDL 432 is then attached on the opposite face of the CCM.

[1276] In the batch process as shown, multiple MEA5 assembly are made concurrently, followed by laser 441 singulation along defined cut line 440 shown in FIG. 47 to separate them into discrete components ready for assembly into a fuel cell array. Methods to assemble the fuel cell are further elaborated in the application Advanced Fuel Cell: Design, Apparatus and Fabrication. Because the GDL comprises a laterally-unform carbon sheet with no defining features, no alignment is necessary when attaching the two GDLs to the CCM. Instead the final shape of the IEM is defined by its laser singulation step cutting through the GDLs 432 and 435 and through the wider exoskeletal pillars 401 surrounding individual IEMs.

[1277] The completed five-layer MEA5 following singulation is shown in FIG. 48. Features from top to bottom include gas diffusion layer GDL 432, catalyst layer 430, ion exchange membrane 410, endoskeleton 402 and surviving portion of the exoskeleton 401x, catalyst layer 415, and gas diffusion layer GDL 435. FIG. 49 illustrates the IEM as a seven-layer MEA7 after addition of bipolar plate 442 contacting GDL 432 and bipolar plate 443 contacting GDL 435. The juxtaposition of bipolar plate 442 and GDL 432 form gas channel 444. Similarly on the other side of the IEM bipolar plate 443 and GDL 435 form gas channel 445. Depending on the type of fuel cell the specific gases carried in gas channels 444 and 445 differ for the anode and cathode side of the MEA7.

[1278] To further elucidate the structure of the membrane matrix during fabrication, a concurrent depiction of the top view of the matrix frame and a side view of the skeleton/membrane/frame can be illustrated at various steps in the process. FIG. 50 illustrates the top and side views of matrix frame 352 after frame and skeletal molding. Located laterally within the outer frame 352 is a matrix of multiple IEM defined by exoskeletal grid including peripheral lateral and vertical components 356a and 356c connected to the outer matrix frame on the periphery by tie bars 353. At this step in fabrication, the openings in membrane frame 355x and 355y located between the inner edge of frame 352, the outer edge of peripheral exoskeleton 356a and 356c, and betwixt tie bars 353 is unfilled but will later be filled with the same ionomer as formed within the IEM membrane.

[1279] Other exoskeletal pillars 356b transecting the matrix array separate it into individual IEMs, in this example comprising vertically oriented pillars. Depending on the design and number of peripheral exoskeleton pillars 356a and 356c, and transecting exoskeletons 356b and more, together, collectively as exoskeleton 356, may form a membrane matrix having multiple rows and/or columns of IEMs. Contained within each exoskeleton-bound IEM is a grid of endoskeletons 354 defining square or rectangular areas 355z where the ionomer membrane is to be subsequently formed. FIG. 51 illustrates the membrane matrix frame after forming polymeric ionomer 355 in previously unfilled openings 355z. The polymer must laterally adhere and bond to the endoskeleton 354 to form a stable film. In FIG. 52 catalyst layers 415 and 430 are formed onto the membrane and skeleton 354.

[1280] In FIG. 53, the gas diffusion layers are attached to form a MEA5. Specifically GDL 432 is attached to catalyst layer 430 of the CCM while GDL 435 is attached to catalyst layer 415 of the CCM. The height of GDL 435 is constrained vertically by the matrix frame. The outer GDL 432 located on the flat side of the asymmetric matrix frame may be the same dimension as the inner GDL 435 or may be larger.

[1281] FIG. 54 illustrates the cut lines through the exoskeletal grid of the membrane matrix and frame including vertical cut lines 440y and horizontal cut lines 440x. Cuts performed between any two adjacent IEMs separate the IEMs from one another while cuts between the edges of IEMs abutting the frame separate the IEMs from matrix frame 352.

[1282] FIG. 55 illustrates the top view and cross section of the resulting discrete IEM comprising the remaining width of the exoskeleton after cutting 356x, the endoskeletal grid 354, the thin ionomer 355. The CCM three-layer MEA3 including catalyst layers 430 and 425 is bounded by GDLs 432 and 435. During cutting the 432 GDL side of the membrane assembly may be attached to sticky tape, often referred to as blue tape, to hold the IEMs in place during cutting.

[1283] Once singulated, the individual IEMs can be removed from the sticky tape and assembled into the fuel cell assembly. In one embodiment, the singulated MEA5 are removed from the sticky tape using a pick and place machine and loaded into the fuel cell stack or stack with no human handling. In this case, the elimination of handling by factory automation reduces the risk of damage to the membrane and improves manufacturing yield and quality.

[1284] In contrast to the foregoing asymmetric frame method, a symmetric membrane matrix frame concurrently fabricating IEM1 through IEM5 membranes 301a-to-301e is shown in FIG. 56 including matrix frame 451 and clamp 450 vertically centered around ionomer membrane 451 and associated exoskeleton 452 and endoskeleton 453. Top view of IEM2 reveals exoskeletal support and endoskeletal pillars 453 form a waffle like grid to support ionomer film 451.

[1285] FIG. 57 illustrates a close up of IEM1, the membrane closest to the matric frame 450. Note that although the outer exoskeleton 452a could be merged into matrix frame 450, because they are different in thickness, it is advantageous to insert as space 450x shown in the regular cross section to in the provide some degree of flexing to prevent breakage. At regular intervals add support to the frame is provided by tie bars 352x merging exoskeleton 452a to matrix frame 450.

[1286] To form a symmetric frame vertically disposed around a matrix of IEM membranes, the molding process is more complex than in a symmetric design. As shown in FIG. 58, a mold chamber comprising base 451 and sidewalls 460 is filled with a tri-layer mold chase, the mold chase being a precision milled steel insert than limits the dimensions of the mold during dispersion casting, injection molding, or transfer molding.

[1287] The bottom and top mold chases 462 and 464 respectively are solid and of the same dimension. The inner or intermediate mold chase 463 also has the same exterior dimensions but includes openings 452z and 453z of varying widths which later will correspond to exoskeleton 452 and endoskeleton 453. The stack of aligned mold chases includes a lateral gap 450z separating it from the sidewall of the mold chamber 460. This dimension of gap 450z is controlled by spacers or registration keys not shown inn the figure cross section.

[1288] In FIG. 59, gap 450z is filled by a polymer dispersion such as PTFE or a hydrocarbon polymer and optionally with strengthening fillers such as carbon fibers, graphene, plastic shards, electrospun fibers, or carbon nanotubes and polymerized to form matrix frame 450. In FIG. 60, top mold chase is removed and openings 452z and 453z are filled with a polymer dispersion such as PTFE and optionally with strengthening fillers such as carbon fibers, graphene, or carbon nanotubes to form pillars 452 and 453 coplanar with the top of inner mold chase 463. If the ionomer slightly overflows slightly onto the top of intermediate mold chase 463 it has no substantive impact on the thickness of the film or its electrical properties. FIG. 61 illustrates the skeletal fabrication step after polymerization.

[1289] In FIG. 62, the intermediate mold chase 463 is removed leaving the frame 450 and fabricated skeletal pillars 452 and 453 intact. The chamber is then filled with a prescribed quantity of mold compound 454z, pressured by mold cap/press 466a in FIG. 63 then heated by mold cap/press 466a in FIG. 64 to form polymerized ionomer 454 shown in FIG. 65. Depending on the polymer's formulation, during the polymerizing process the height of ionomer 454 may shrink slightly below that of pillars 452 and 453.

[1290] In the step illustrated by FIG. 66, handle 467 is attached to the matrix comprising ionomeric membrane 454 and pillars 452 and 453. If the pillars are taller than ionomeric membrane 454, a small gap 468 mat result whereby handle 467 attaches to only pillars 452 and 453. The lateral extent of the handle must be at a dimension smaller than the interior edge of matrix frame 450. Removing the matrix from the mold with handle 467 still attached is shown in FIG. 67.

[1291] Flipping the assembly over for anode catalyst deposition 465a is shown in FIG. 68 where mechanical support and heating during deposition is provided by handle 467 sitting atop heated vacuum chuck 469. As described previously a nanocoating may be formed between the membrane polymer and the catalyst layer, as nanospheres or permanent fillers within the catalyst layer, or between the catalyst layer and the GDL. After anode catalyst deposition, catalyst layer 470 is formed atop membrane 454 and peripherally deposited as unfunctional layer 470f atop frame 450 as depicted in FIG. 69. Because the thickness of handle 467 is thicker than the height of frame 450 the frame does not effect attachment of membrane matrix and handle 467 to vacuum chuck 469.

[1292] The handle is then removed from the cathode and reattached to the anode side of the film. As shown in FIG. 70 and FIG. 71, the cathode catalyst layer is then deposited 465c onto the cathode side of the membrane while heat is supplied from vacuum chuck 469 via handle 467. As described previously, a nanocoating may be formed between the membrane polymer and the catalyst layer, as nanospheres or permanent fillers within the catalyst layer, or between the catalyst layer and the GDL. The deposited CL film comprises active catalyst layer 471 formed atop ionomer 454. Deposition of catalyst 471 formed atop the skeletal pillars 452 and 453 along with layer 471f deposited on frame 450, like 470f are electrically inactive. In FIG. 72, gas diffusion layers 472 and 473 are attached to the CCM while clamp 475 holds frame 450 resulting in the five layer MEA5 of FIG. 73.

[1293] In FIG. 74, symmetric matrix frame 450 held by clamp 475 including IEM membrane 454 and integral skeleton elements 452 and 453 sandwiched by catalyst layers 470 and 471 and enclosed by GDL layers 472 and 473 are singulated by laser 475 along cut lines 476. The resulting singulated IEM is shown in FIG. 75. After attachment of bipolar layers 477 and 478 to GDL layers 472 and 473 respectively, the resulting seven layer MEA7 is shown in FIG. 76.

[1294] Regardless of whether the matrix frame is symmetrically or asymmetrically positioned around the membrane itself, or eliminated altogether, the concurrent fabrication of multiple IEMs using a batch process is beneficial as it reduces process variability, improves electrical and chemical consistency, increases production throughput, and lowers manufacturing cost. Beneficial embodiments of the inventive IEM fabrication methods using the inventive membrane matrix frame are numerous, including: [1295] accurate control film thicknesses and dimensions via precision molds; [1296] rigid skeletal support of ultra thin ionomeric membranes during manufacturing and operation; [1297] rigid skeleton support including a peripheral exoskeleton and a thinner endoskeletal grid reduces film swelling from over hydration during operation; [1298] ability to control skeletal and frame strength and rigidity using carbon fiber or other reinforcing materials such as carbon nanotubes, graphene, or fibrous plastics; [1299] larger mechanical support frame for improved manufacturing by automated or robotic handlers; [1300] matrix frame is capable of concurrently fabricating any number of IEMs including a matrix of rows and/or columns of IEMs bounded by a wider exoskeleton; [1301] eliminates handling related film damage causing yield loss or latent reliability failures; [1302] eliminates human contamination of films during assemblyclean room compatible; [1303] able to support any ionomer including bulk conduction and surface conduction type; [1304] consistent polymerization of ionomer under conditions of controlled pressure and temperatures; [1305] capable of employing different materials on the anode and cathode of a CCM; [1306] capable of attaching GDLs to the CCM prior to singulation eliminating the need to handle discrete IEMs during catalyst coating and during MEA5 fabrication, i.e. attaching the GDLs; [1307] stress free laser singulation eliminates mechanical damage and tears in membranes; and [1308] batch process capable of supporting high volume production at lower costs.

[1309] The methods as described are compatible with any type of ionomeric membrane including fluorocarbon and hydrocarbon chemistries, homo-ionomer or hetero-ionomer membranes, with or without skeletal support or nanocoatings. The methods may be used in conjunction with microporous membranes fabricated using a sacrificial filler process, and/or combined with permanent fillers comprising bismuth compounds, graphene oxides, pristine and functionalized carbon nanotubes, silicates, zeolite, zirconium, tungsten, nanofibers, nanospheres, MOFs, and POSS.

Membrane Synthesis.

[1310] Although the process to fabricate the inert membrane matrix frame employs polymer chemistry relatively agnostic to the ionomer it supports, other embodiments involve the formation of the polymer itself. Ionomer chemistry depends on the conducting ion charge, either positively-charged ionized protons H.sup.+ or negatively-charged hydroxyl radicals OH. As such, in a fuel cell two different charge transport polarities are possible. Positive charge conducting IEMs are referred to as cation exchange membranes or more commonly known as proton exchange membranes with the acronym PEM. Negative charge conducting IEMs are referred to as anion exchange membranes or AEMs.

[1311] The chemistry of the membrane and the catalyst also vary with the chemical source of the charge whether gaseous hydrogen, sodium hydroxide, acids, or glucose. While not all fuel cells produce carbon free byproducts, most fuel cells effluents comprise water, i.e. H.sub.2O in liquid or vapor form. The presence of water in the fuel cell also affects the cell's operation either beneficially or to the detriment of its operating efficiency.

[1312] The electrochemistry of a fuel cell, using ionic transport through a membrane to create electricity is a generally reversible process in the cases of simple inorganic molecules such as hydrogen or hydroxide. This inverse process, making hydrogen from water or from alkaline water is referred to as electrolysis. The PEM and AEM membranes useful in fuel cells are generally also adaptable for use in electrolysis except that the membrane's area, chemistry, and catalysts may vary from their fuel cell counterpart.

[1313] Although glucose can be converted into electricity in a glucose fuel cell, the reverse process for electrolysis is not symmetric but instead converts glucose into hydrogen and various organic byproducts including commodity chemicals like sorbitol, 5-hydroxymethylfurfural, gluconic acid (GNA), and glucaric acid (GRA). GRA is considered a key intermediate for the production of biodegradable polymers and biodegradable detergents, as a metal complexation agent, and in pharmacology in chemotherapy and statin production.

[1314] The greatest commercial interest in ion exchange membrane is focused on hydrogen PEM fuel cells (H.sub.2 PEMFCs) and in PEM-based direct methanol fuel cells (DMFCs) where the lion's share of content in the application is focused. Specific examples of PEM membranes fabricated for various use cases are described here below.

Ionomeric PEM Fabrication.

[1315] In various embodiments of this invention, the fabrication of a PEM proton exchange membrane also referred to as a polyelectrolyte membrane involves a sequence of process steps that differ substantially from conventional membrane processing. The disclosed processes can be divided into two inventive methodsone synthesizing a surface conduction heterogenous ionomeric membrane, the other forming a homogenous bulk conduction ionomer whereby the primary difference is the way charge transport occurs. Either membrane formation method is compatible with the inert skeletal support structure described previously.

[1316] Specifically, the chemistry of forming a heterogenous PEM film is entirely dependent on the synthesis process required to form a resilient chemical bond between the hydrophobic backbone comprising an inert polymer such as PTFE and the hydrophilic ionomer involved in conduction. This process, can be achieved by co-polymerization, i.e. simultaneous formation of hydrophobic and hydrophilic elements bridged by an intervening sidechain pendant, or by grafting. In grafting a process for attaching sidechains to an inert long chain such as a PTFE backbone, the terminus of the sidechain comprises electrically active charge transfer molecules such as sulfonic acid, sulfonated pentablock terpolymers, and non-fluorinated ionomers such as sulfophenylated polyphenylene.

[1317] Unlike copolymerization which depends in the mutual compatibility of monomers and acid groups with cross-linking reagents and solvents during polymer formation, grafting depends on the chemistry of a molecular coating process performed subsequent to a membrane's structural synthesis. Simply put, in grafting a specific sequence of chemical reagents and/or radiation exposures are required to modify a hydrophobic backbone in order to graft a sidechain pendant and an associated hydrophilic ionomer onto its structure.

[1318] One exemplary process sequence is illustrated in FIG. 77A. As shown, after forming a PTFE supportive film 500 comprising molecular matrix 500z, the inert membrane is treated with reagents to facilitate bonding between the PTFE backbone and its hydrophilic pendant sidechains and ionomer. In one embodiment, polyvinyl alcohol, aka PVA solution 501 is used to treat the PTFE membrane. Having a molecular weight of 85,000-to-124,000, the PVA functions as an interfacial modifier. Polyvinyl alcohol, a water-soluble synthetic polymer [CH.sub.2CH(OH)].sub.n or simply described as (C.sub.2H.sub.4O).sub.x can be formed by partially or completely hydrolyzing polyvinyl acetate. The conversion of the polyvinyl esters is usually conducted by base-catalyzed transesterification with ethanol via the reaction

##STR00007##

where the symbol OAc represents the molecule acetoxy, chemically as OCOCH.sub.3 and structurally as OC(O)CH.sub.3 where the double bar symbol=means a double bond, not the equal sign in mathematical equation.

[1319] The properties of the resulting PVA polymer are affected by the degree of transesterification. PVA can be procured commercially in solution or made from PVA powder. For example, in small quantities PVA can be mixed by dissolving 4 g of PVA powder in 40 ml of deionized water and subsequentially mixed with a magnetic stirrer at 90 C. for 3 h until completely dissolved. In manufacturing, the solution can be purchased in volume and stirred at 90 C. immediately upon use.

[1320] The PVA treatment of the IEM matrix may be performed by immersing the fabricated membrane in the heated solution for between 3-to-24 hours. In one implementation made in accordance with this invention, the ion exchange membrane frame is occasionally removed from the PVA solution and rinsed in deionized water to remove any PVA particulates. As shown, the PVA treated PTFE film 502 comprises a coated hydrophobic backbone 502z to facilitate subsequent grafting to hydrophilic side groups of PFSA. The final PTFE thickness is then precisely controlled by a precision pressure mold, using a doctor blade process, or by the amount of material molded.

[1321] Thereafter in step 503 the membrane is spray coated with a PFSA solution comprising a solvent comprising a 1:1 weight percent ratio of deionized water and propanol mixed with a 0.5 weight percent of PTFE nanoparticles (NPs) to chemically neutralize the surface. The matrix frame is then held in a 60 C. oven for drying for approximately eight hours followed by a 150 C. anneal for thirty minutes resulting in PFSA-PVA-PTFE film 504 with polymerized microstructure 504z.

[1322] FIG. 77B represents an exemplary flow chart for fabricating ion exchange membranes made in accordance with this invention, with the resulting film comprising either interfacial or bulk conduction. The process commences with step 510 Fabricate Skeleton to produce an endoskeleton of semirigid pillars including wider exoskeletal elements used for IEM singulation by laser or mechanical cutting, and optionally a thick wide frame for mechanical or robotic handling during fabrication.

[1323] The next step 511 Add Intercalated Sacrificial Layer involves introducing a filler into the mold or cast such as sugar, chitosan, or other water or solvent soluble molecules to control film microporosity. The sacrificial filler may be introduced by blending the filler in solid form into a mix of monomers used to create the thin membrane or by dissolving the filler and monomers with a solvent into solution for casting. According to Miriam-Webster, the term intercalated means to insert or position between or among existing elements or layers. In the context of a molecular lattice of a polymer or crystal, the intercalated sacrificial filler represents a molecule temporarily occupying space within the lattice to reduce the atomic density of the polymer thereby increasing microporosity. Although the size of micropores affect transmembrane water transport in both interfacial and bulk conducting films, porosity has a more profound effect in bulk materials.

[1324] In the case of forming an interfacial conduction IEM, the sacrificial filler is mixed with monomers of an inert electrically-insulating material co-molded with the sacrificial layer using cast molding in step 514 Form Inert Membrane during which polymerization of the constituent monomers occurs via cross linking optionally aided by heating and/or mild pressure. During casting or molding, the sacrificial molecules becoming embedded into molecular matrix of the polymer or glassy polymer.

[1325] After cooling, the polymer is treated to dissolve and remove the sacrificial filler from the matrix using a corresponding solvent as depicted in step 515 Remove Sacrificial Filler. The film may be subsequently washed or cleaned in water or other solvents, soaked in solvents, and/or heated in step 516 Treat/Cure Membrane in order to prepare the semi-insulating membrane for a subsequent coating step to enable electrical conductance.

[1326] In step 517 Coat Active Ionomer onto Membrane, the insulating polymeric substrate is coated with a conducting ionomer which bonds to surface of polymer strands either through surface tension or covalent bonding, thereby grafting hydrophilic functional groups such as sulfonic or phosphonic acid onto the polymer chains. The details of the graft or bond depend on the process used in preceding step 516.

[1327] Bonds for example may between the mainchain and a sidechain or pendant molecule may occur by various mechanisms including (i) attachment at a damage site created by a chemical reagent or by radiation treatment; (ii) attachment by a chemical substitution reaction where one or more atoms of the mainchain become replaced, e.g. substituting fluorine with carbon or oxygen to enable covalent bonding between the polymer backbone and sidechains; (iii) entanglement where one end of the sidechain becomes physically enveloped, i.e. tangled, with the 3D structure of the polymer's mainchain tethering the sidechain pendant and its acid terminus to the membrane's molecular matrix; or (iv) intertwining, where the molecular strands of two polymers, one inert and hydrophobic, the other hydrophilic and bonded to ionomeric termini, become so entwined they cannot be separated or untangled. Despite their repulsive forces, hydrogen bonding and Van der Waals forces occurring intermittently along the chains prevent the two incompatible chains from unwinding and dissociating.

[1328] In other cases, a cross linking agent such polydopamine or glutaraldehyde can secure the molecular structures to one another. In the special instance of inserting conductive ionones into the mainchain itself rather than by attaching a sidechain, the mainchain must be cleaved or severed to accommodate the insertion, a physical chemical process analogous to the way an endonuclease can sever deoxyribose in biochemistry.

[1329] Regardless of the molecular bonding mechanism in step 517 Coat Active Ionomer onto Membrane, the terminology does not simply mean to coat the exterior face of the membrane with an ionomeric coating but to encase the individual strands of the hydrophobic polymeric strands with a sheath of conducting sidechains and acids. The conductive encasement formed by the molecular coating process, analogous to myelin coating of nerves or insulation coating a wire, enables conduction along the length of the hydrophobic polymer strands, in essence forming surfaces for surface conduction within the polymeric or glassy matrix of the membrane.

[1330] Step 517 may also include introduction of a solute matrix of nanoparticles carried by a solvent. For example if the inert structural matrix formed in step 514 comprises PTFE and the monomers introduced in coating step 517 is a spray or solution of PTFE, PFSA and PVA, then in step 518 Treat/Cure Ionomer a thin layer of conductive channels of PFSA ionomeric conductors is formed along the spine of the PTFE mainchains. To strengthen the bonds, the PTFE membrane or skeleton is sprayed with PVA, washing the film with ethanol, then stimulating cross linking to the polytetrafluoroethylene surface using glutaraldehyde. Alternatively PVA may be cross linked to poly(acrylic acid-co-2-acrylamido-2-methyl propane sulfonic acid), chemically as (P(AA-AMPS)), to enhance stability.

[1331] In other variants, the polymer may comprise or fluorocarbons forming glassy matrices or may comprise low-fluorine or fluorine-free compounds. For example, other composite membranes made in accordance with this invention involve bonding using PVA with inorganic zirconium phosphate to form a highly-stable composite membrane of PTFE-ZrP-PVA. Thereafter, the film is ready for subsequent CCM processing in step 519 Catalyst Layer Processing. The resulting structure is an endoskeletal-supported composite reinforced membrane CRM which primarily conducts ions via ionomer pendants such as PFSA adhering to and attached along the PTFE chain.

[1332] The resulting ionomer is therefore a heterogenous film and IEM. Fabricating a bulk conducting film is also represented in the same flow chart commencing with formation of the skeletal support in step 510 to produce an endoskeleton of semirigid pillars including wider exoskeletal elements used for IEM singulation by laser or mechanical cutting, and optionally a thick wide frame for mechanical or robotic handling during fabrication. The next step entitled Add Intercalated Sacrificial Layer involves introducing a filler into the mold or cast such as sugar, chitosan, or other water or solvent soluble molecules to control film microporosity.

[1333] The sacrificial filler is then mixed with monomers of a hydrophilic electrically-conductive ionomeric material co-molded with the sacrificial filler using pressure or thermal cast molding in step 512 Form Ionomeric Membrane. In this process, also referred to as co-molding the sidechain and the mainchains are formed concurrently and covalently bound during the polymerization process. By integrating two hetero-monomer segments, i.e. a di-monomers, alternating between pristine hydrophobic mainchain segments and those containing sidechain pendants with hydrophilic ionomeric termini, the ionomer's equivalent weight (EW), i.e. the mole fraction of conductive ionomer groups, can be regulated.

[1334] For example, the ionomers Nafion, Aquivion, 3M, etc. comprise PFSA-PTFE di-polymer formed by a linear mainchain of hydrophobic TFE segments of (CF.sub.2CF.sub.2) alternated with a second monomer having a single oxygen substitution of fluorine, namely (CFOCF.sub.2) where the oxygen forms a second bond with a sidechain pendant with a hydrophilic ionomer terminus. The equivalent weight (EW) is defined as the number of grams of dry polymer per mole sulfonic acid (SO.sub.3) determined by the average distance between the side chains along the backbone, i.e. the occurrence frequency of the second monomer segment. Commercial equivalent weights range from 700 to 1200 for the PFSA class of fluorocarbon based membranes. The combination of a long inert mainchain with multiple sidechain pendants is sometimes referred to as a comb polymer because of its structural shape.

[1335] Partially fluorinated membranes include segments containing glass like compounds rather than PTFE. Examples include hydrolyzed perfluoro-(2,2-dimethyl-1,3-dioxole) (PDD) and poly(perfluoro-2-methylene-4-methyl-1,3-dioxolane) (PFMDD). Di-monomer based membranes also are common in hydrocarbon based polymers include polyethylene (PE), polyvinyl chloride (PVC), phenylsulfonyl-poly(benzoyl-phenylene) (PhSO)P(BzPh); poly phosphazene P(Pz); and poly siloxane P(Sx). Other forms of polymers contain multiple dissimilar segments on their mainchain. Examples include hybrid heteropolymers of hydrocarbons such as poly arylene ether sulfone (PAES, PAESf), poly arylene ether matrix (PAEM); poly(ether ketone) (PEK), poly(ether sulfone) (PES, PESf); poly(ketone sulfone) (PKS, PKSf); poly(arylene ketone ether sulfone) (PAKES, PAKESf); and poly(arylene ether sulfone) triazine bisphenol (PAES)(TzBPh).

[1336] A large class of copolymers employs linking molecules to complete a heterogenous mainchain or cross-linked chains. Examples include a large number of poly vinyl difluoride compounds (PVDF-co-X) where X may represent any number of monomeric segments including perfluorostyrene, polyphenylene quarter-Ph, polyamide sulfonimide, polyvinyl alcohol, PVP polystyrene, F.sub.6 propylene, and others. A key element to the assembly of copolymers is the inclusion of amphiphilic molecules to facilitate linking. An amphiphilic or amphiphatic molecule is one having both hydrophobic (nonpolar) and hydrophilic (polar) regions to facilitate bonding. One other class of copolymer comprises large subunits known as blocks assembled in a linear sequence, often with amphiphilic linkers contained within.

[1337] Returning to FIG. 77B, following polymerization in step Form Ionomeric Membrane in step 512, the sacrificial filler is dissolved and removed in step 513 Remove Sacrificial Filler using a corresponding solvent. For example if the sacrificial filler is sugar, the solvent may be water. The film may be subsequently washed or cleaned in water or other solvents, soaked in solvents, and/or heated in step 518 Treat/Cure Ionomer in order to strengthen the PFSA bonds within the polymer and between the ionomer and the skeleton. In this process the PTFE membrane or skeleton is sprayed with PVA, washing the film with ethanol, then stimulating cross linking to the polytetrafluoroethylene surface using glutaraldehyde. Alternatively PVA may be cross linked to poly(acrylic acid-co-2-acrylamido-2-methyl propane sulfonic acid), chemically as (P(AA-AMPS)), to enhance stability in preparation for catalyst layer formation in step 519.

[1338] Exemplary films made in accordance with this invention are shown in the samples shown in FIG. 78 including (a) photo, (b) cross section, (c) top view, and (d) alternative cross section. Exemplary test devices confirm the benefit of scaling the PEM membrane thickness in a surface conducting ionomer fuel cell. After synthesis, the fabricated membranes were assembly into a single layer fuel cell assembly and electrically characterized.

PEM Measured Electrical Characteristics.

[1339] As shown in FIG. 79A, a lab fabricated test PEM comprising a composite PFSA-PVA-PTFE composite reinforced membrane (CRM) of 100 m thickness exhibits a voltage-current characteristic curve 521 at a relative humidity of 50%. This electrical characteristic 520, sometimes referred to as a polarization curve exhibits slightly better characteristics than curve 520 measured on a Nafion based fuel cell of the same thickness. Scaling a CRM reinforced composite membrane to thinner film thickness beneficially improves conductance as shown by curve 522 for a 50 m PEM and curve 523 for a 20 m PEM.

[1340] Multiplying the conducted current density value times the measured cell voltage results in the power density curves shown in FIG. 79B exhibiting peak power at around 200 mA/cm.sup.2 at RH=50%. These curves include conventional Nafion PEM characteristic 525 and CRM curve 526 both comprising 100 m films CRM curves 527 at 50 m and 528 at 20 m exhibit 20% and 30% higher power densities respectively than conventional PEM curve 525, peaking at a measured power 350 mW corresponding to a membrane conductivity of 45 mS/cm. At RH=100%, the conductance improves to 85 mS/cm.

[1341] Scaling the membrane's active area to mA.sub.FC=120 cm.sup.2 means a fabricated cell using the fabricated film will deliver 12 W at a current of 24 A and a cell voltage of V.sub.FC=0.5 V. The described CRM fabrication process demonstrated does not include any provisions for enhancing the porosity of the PTFE web-like framework reinforcing the film nor does it include the semi-rigid skeleton disclosed previously.

[1342] Use of the term polarization curves to describe the voltage-current characteristics of a fuel cell is a bit misleading as not all the electrical effects in a fuel cell relate to polarization related losses. Some effects, for example ohmic losses occurring in conductors such as the bipolar plates, are in fact not related to polarization while other loss mechanisms are. More broadly the losses can be categorized into four componentsa lossless polarization voltage V*, activation losses, ohmic losses, and concentration or transport losses.

[1343] The lossless component V* represents the zero current voltage differential between the ideal cell voltage V.sub.chem and the fuel cell's open-circuit terminal voltage V.sub.FC(I=0.sup.+)=V.sub.OC at the onset of conduction. This voltage differential is similar to a contact potential. Since this V* potential is overcome electrostatically, i.e. requiring no DC current, the voltage V.sub.chem is not meaningful in calculating efficiency of a fuel cell membrane or in power losses. Instead the open circuit voltage V.sub.OC neglecting the lossless component V* is a better reference when calculating efficiency. As such, the fuel cell efficiency can be calculated by .sub.FC=V.sub.FC/V.sub.OC where the fuel cell voltage is a function of current, temperature, and relative humidity V.sub.FC=f (I.sub.FC, T, RH). Importantly, by maintaining temperature and relative humidity, a membrane's polarization curve allows extraction of numerous electrical properties of an ion exchange membrane including power output, conversion efficiency, heat generation, resistance and resistive losses, activation losses, and the onset of high current concentration losses.

[1344] Specifically the power generated by the fuel cell is given by the fuel cell's voltage V.sub.FC at a specified current whereby P.sub.FC=I.sub.FCV.sub.FC. The power output can be converted into power density by dividing its current I.sub.FC by the fuel cell's active area A.sub.FC in which power density in mW/cm.sup.2 is calculated as (P.sub.FC/A.sub.FC)=[I.sub.FC/A.sub.FC](V.sub.FC) where V.sub.FC is a function of current density. Similarly power input to a fuel is given by its open circuit voltage V.sub.OC multiplied by its current I.sub.FC or current density I.sub.FC/A.sub.FC, as given by either P.sub.in=I.sub.FCV.sub.OC or by (P.sub.in/A.sub.FC)=[I.sub.FC/A.sub.FC](V.sub.OC) where V.sub.OC=V.sub.eff=V.sub.chemV* and where V* is the voltage drop due polarization at I.sub.FC=O.sup.+.

[1345] As defined thermodynamically or electrodynamically, conversion efficiency .sub.FC of a fuel cell is defined as its by the power output V.sub.FC divided by its power input P.sub.in or simply .sub.FC=P.sub.FC/P.sub.in=V.sub.FC/V.sub.OC where P.sub.FC and V.sub.FC are a function of I.sub.FC or I.sub.FC/A.sub.FC. The resulting equation if current in amperes (A) is replaced by current density in mA/cm.sup.2. In other words, the efficiency of a fuel cell at a specific current or current density is the ratio of its measured voltage to the open circuit voltage. For example, for Nafion polarization curve 520 operating at a current density of 50 mA/cm.sup.2 the fuel cell voltage is measured to be V.sub.FC=0.67V while the voltage at I.sub.FC=0.sup.+ is V.sub.OC=0.94V. Substituting the measured values into the expression, the corresponding empirical efficiency as defined by the ratio of the two is thereby .sub.FC=P.sub.FC/P.sub.in=V.sub.FC/V.sub.OC=(0.67V)/(0.94V)=71% whereby activation losses are (100%.sub.FC)=(100%71%)=29% The activation voltage V.sub.a=V.sub.OCV.sub.FC=0.94V0.67V=0.27V.

[1346] In direct comparison, the polarization curves of fuel cells comprising membranes made in accordance with this invention include 100 m composite reinforced membrane (CRM) shown by curve 521 with V.sub.FC=0.72V, an activation voltage V.sub.a=V.sub.OCV.sub.FC=0.94V0.72V=0.22V and a corresponding loss of (1.sub.FC)=1(0.72V)/(0.94V)=(100%77%)=23%. Because the membrane is reinforced it can be scaled to higher performing thinner membranes. For example, curve 522 for a 50 m film exhibits a voltage at 50 mA/cm.sup.2 at V.sub.FC=0.80V, an activation voltage V.sub.a=V.sub.OCV.sub.FC=0.94V0.80V=0.14V and a corresponding loss (1.sub.FC)=1(0.80V)/(0.94V)=(100%85%)=15%. By comparison, curve 525 for a 20 m film exhibits a voltage of V.sub.FC=0.83V, an activation voltage V.sub.a=V.sub.OCV.sub.FC=0.94V0.83V=0.11V and a corresponding loss (1.sub.FC)=1(0.83V)/(0.94V)=100%88%=12%.

[1347] As demonstrated in the below table activation voltage of membranes made in accordance with this invention improved by 2.7 reducing from 270 mV and a 29% power loss to 110 mV with only a 12% power efficiency reduction. Because of the reduced activation loss, the membrane resistance R.sub.memb averaged across the ohmic region decreases from 2.5 cm.sup.2 down to 1.4 cm.sup.2.

TABLE-US-00008 Membrane V.sub.FC @ 50 mA/cm.sup.2 Activation V.sub.a 1 .sub.FC Ohmic R.sub.memb @ I.sub.FC/A.sub.FC = 175 mA/cm.sup.2 100 m Nafion 0.67 V 270 mV 29% R = (0.94 V-0.50 V)/(I.sub.FC/A.sub.FC) = 2.50 cm.sup.2 100 m CRM 0.72 V 220 mV 23% R = (0.94 V-0.53 V)/(I.sub.FC/A.sub.FC) = 2.30 cm.sup.2 50 m CRM 0.80 V 140 mV 15% R = (0.94 V-0.63 V)/(I.sub.FC/A.sub.FC) = 1.8 cm.sup.2 20 m CRM 0.83 V 110 mV 12% R = (0.94 V-0.69 V)/(I.sub.FC/A.sub.FC) = 1.4 cm.sup.2

[1348] As evidenced by a change in slope, above current densities of 50 mA/cm.sup.2, DC losses are primarily ohmic in nature including the chemical diffusion resistance involving cation conduction across the membrane and purely resistive losses for conducting electrons out of the fuel cell or fuel cell stack. At higher currents, e.g. over 175 mA/cm.sup.2 concentration losses begin to impede carrier transport including water logging, membrane swelling, and other transport effects.

[1349] The overall electrical behavior can be modelled as a lumped element model shown in FIG. 80 comprising open circuit voltage 540 of magnitude V.sub.chem is series with a current-dependent counter-opposing voltage source 541 modelling chemical polarization effects of magnitude V.sub.pol, a current dependent membrane impedance 542 of magnitude Z.sub.memb with a real component Re{Zmemb} representing dynamic membrane resistance R.sub.memb, and a constant ohmic resistance 544. In this manner the terminal voltage of a fuel cell can be expressed as by the equation

[00020]$V_{\mathrm{FC}}=V_{\mathrm{chem}}-V_{\mathrm{pol}}-.Math.\left(Z_{\mathrm{memb}}+R_{\mathrm{ohmic}}\right)V_{\mathrm{eff}}-.Math.\left(R_{\mathrm{memb}}\right)$

where the dynamic impedance 543 of magnitude Z(t) is given by

[00021]$Z\left(t\right)=\frac{V^{*}}{I}+Z_{\mathrm{memb}}$

and where real components V.sub.effV.sub.chemV* and R.sub.memb=Re {Z.sub.memb}>>R.sub.ohmic. The ideal FC voltage 540, FC polarization voltage V*, and DC membrane resistance 102 are all functions of temperature T, relative humidity of the anode RH.sub.A, relative humidity of the cathode RH.sub.C, and current density I/A.

[1350] Even at zero current when resistive losses are diminutive, the fuel cell voltage V.sub.FC still remains less than the electrochemical potential V.sub.chem because of contact potential, i.e. the work function between dissimilar materials present in the cell's construction. As such, a fuel cell cannot deliver any power at the voltage V.sub.chem. More precisely, the maximum possible voltage of an unloaded fuel cell is given by V.sub.FC=V.sub.chemV* where V* the minimum polarization voltage is non-zero.

Bulk Conducting Ionomer PEM.

[1351] Another approach to forming a PEM membrane made in accordance with this invention is to employ a homogenous ionomer with added support in the active conducting areas. While pure ionomeric films suffer from swelling and risk mechanical damage during handling, in one embodiment of this invention the combination of the disclosed semi-rigid skeleton with a bulk conducting ionomer provides the complementary advantages of both mechanical support and high film conductivity not achievable by CRMs.

[1352] Note that for an ion-conduction mechanism in which water is the transport medium, even very thin hydrophobic barriers can drastically reduce ion conductivity. Accordingly, to overcome this problem, made in accordance with this invention the bulk conducting membrane includes narrow water channels called nanopores to enhance ion transport under low humidity conditions.

[1353] Accordingly, the disclosed bulk conducting membrane comprises a pure PFSA polymer with increased porosity. In one embodiment the enhanced porosity film is formed using a sacrificial filler interspersed within the PFSA matrix. To open pores within the ionomeric polymer, the filler must be present in the dispersion cast or mold at the time of PFSA formation. At the time of polymerization the filler occupies spaces where PFSA monomers would otherwise occupy. After the matrix is polymerized, the filler is removed using any solvent that does not dissolve PFSA. After the filler is dissolved and removed by the solvent, the resulting membrane is washed of any remaining reagents in deionized water and dried. In the spaces of the polymerized matrix the filler previously occupied, now a thermally stable nanopore remains increasing the ionomer's porosity and enhancing proton transport.

[1354] As depicted in the flow chart of FIG. 81, the fabrication sequence for a porous PEM film may vary. In one instance the filler may be mixed together with the ionomer as a solid powder and loaded into a mold 550. The mixed compound is then polymerized and cured with heat and/or pressure 551. In another version the PFSA powder is mixed with filler and dissolved in solution 552. The ionomer solution is then filled into the mold 553 and heated to dry out the film before it is polymerized and cured with heat and/or mild pressure 554. In another implementation, the filler loaded into the mold in either solid or dissolved form and heated 555 to form a weakly crystalized substrate or quasi-template.

[1355] The PFSA is then dissolved in a solvent 556 and applied onto the crystalized substrate of the filler 557 giving time for the PFSA to soak into the filler crystal. Once thoroughly wetted, the ionomer is baked then polymerized and cured with heat and/or pressure 558. During molding and curing in either steps 551, 554, or 558 the polymer forms in and around the filler. The filler is then subsequently dissolved and removed by a solvent in step 559 followed by a final stabilizing bake 560.

[1356] For illustrative purposes FIG. 82 details a demonstration involving sucrose 565a, i.e. granulated sugar (strawberries not included) loaded into petri dish as the filler 565b. The fine granulated crystal sugar comprise sucrose particles ranging in size between 100 nm to 1 m. PFSA powder dissolved in solution, e.g. using a mix of one part deionized water and one part propanol (1:1 by weight percent), was then poured into the mold containing the sucrose.

[1357] The mixtures were settled for at least 8 h to allow the PFSA solution precursor to fully infiltrate the pores of the sugar template. After curing, the PFSA was subjected to a water bath (at the temperature of 60 C.) in order to dissolve the sugar filler. The porous PFSA film was air dried at 60 C. for half an hour and then carefully detached from the glass substrates and thermally annealed at 150 C. for 30 min to complete the fabrication process.

[1358] The exemplary films fabricated through this process comprise a white porous film 570 shown in FIG. 83 having dimensions 5 cm5 cm or mA.sub.FC=25 cm.sup.2 and of thickness 20 m with an average porosity of 0.6 as shown in FIG. 84. Observed pore size varied by orientation within the film. As measured by scanning electron microscopy (SEM), pore sizes having dimensions comprising 100 nm, 500 nm, and 1 m corresponding to images 571, 572, 573 were fabricated and optically and electrically characterized. These porous PEM films cross sections are contrasted against a PEM top view 575.

[1359] The voltage-current relationship of fabricated porous PEM films 582a, 582b, and 582c is contrasted in FIG. 85A against that of aforementioned 20-m PFSA-PVA-PTFE composite reinforced membrane CRM 581 and 100 m Nafion film 580. As shown, all three porous 20 m thick PEM films 582a with 1 m pores, 582b with 500 nm pores, and 582c with 100 nm pores significantly outperform both the 20 m PFSA-PVA-PTFE composite reinforced membrane CRM 581 and the 100 m Nafion film 580. Benefits include less voltage sag, lower membrane resistance, operation to higher current densities, and most notably a significant reduction in activation losses.

[1360] Although numerous models exist to theoretically predict PEM polarization curves, since we already have measured electrical characteristics, fuel cell parameters can be extracted using a simplified piecewise linear resistance model assuming a fixed zero open circuit polarization voltage of V*=V.sub.chemV.sub.OC where V.sub.OC is the open circuit voltage at the onset of conduction. According to the previously shown graph of FIG. 85A the open circuit voltage V.sub.OC=0.94V.

[1361] If we assume the intrinsic electrochemical fuel cell voltage is V.sub.chem=1.2 V, then V*=V.sub.chemV.sub.OC=1.2V0.94V=0.26V. Since this voltage drop occurs at nearly zero current, it dissipates no power and therefore can be ignored in power and efficiency calculations. Instead the value V.sub.OC=0.94V should be considered the ideal fuel cell voltage by which power loss is calculated regardless of what V.sub.chem is. Accordingly the terminal voltage of the fuel cell as a function of current can be estimated using an effective average resistance R.sub.eff by the equation

[00022]$V_{\mathrm{FC}}=V_{\mathrm{OC}}-I_{\mathrm{FC}}{R}_{\mathrm{eff}}$

with a corresponding power P.sub.L delivered to a load given by

[00023]$P_L=I_{FC}\left(V_{\mathrm{OC}}-I_{\mathrm{FC}}{R}_{\mathrm{eff}}\right)=I_{\mathrm{FC}}{V}_{\mathrm{OC}}-I_{\mathrm{FC}}^2=\left[P_{100}-I_{\mathrm{FC}}^2{R}_{\mathrm{eff}}\right]=P_{100}-P_{\mathrm{loss}}$

where the ideal fuel cell power at one-hundred percent efficiency is given by P.sub.100=I.sub.FCV.sub.OC when the current I.sub.FC=0, where R.sub.eff is the average resistance defined by R.sub.eff=(V.sub.OCV.sub.FC)/I.sub.L, and where the average power loss P.sub.loss dissipated within the fuel cell is P.sub.loss=I.sub.FC.sup.2 R.sub.eff.

[1362] A more accurate description of power loss is a piece wise linear model where the total energy lost is determined by a current dependent variable resistance R.sub.x where

[00024]$P_L=I_{\mathrm{FC}}{V}_{\mathrm{OC}}-P_{\mathrm{loss}}=P_{100}-P_{\mathrm{loss}}$$P_{\mathrm{loss}}=I_1^2{R}_1\mathrm{where}{R}_1=V_1/I_1\mathrm{for}{I}_{\mathrm{FC}}{I}_1$$P_{\mathrm{loss}}=I_1^2{R}_1+\left(I_2^2-I_1^2\right)R_2\mathrm{where}{R}_2=\left(V_2-V_1\right)/\left(I_2-I_1\right)\mathrm{for}$$I_1<I_{\mathrm{FC}}{I}_2$$P_{\mathrm{loss}}=I_1^2{R}_1+I_2^2{R}_2+\left(I_3^2-I_2^2\right)R_3\mathrm{where}{R}_3=\left(V_3-V_2\right)/\left(I_3-I_2\right)\mathrm{for}$$I_2<I_{\mathrm{FC}}{I}_3$$P_{\mathrm{loss}}=I_1^2{R}_1+I_2^2{R}_2+I_3^2{R}_3+\left(I_4^2-I_3^2\right)R_3\mathrm{where}$$R_4=\left(V_4-V_3\right)/\left(I_4-I_3\right)\mathrm{for}{I}_3<I_{\mathrm{FC}}{I}_4$

and so on. As a discrete series summation P.sub.loss can be expressed as

[00025]$P_{\mathrm{loss}}=\underset{0}{\overset{n}{.Math.}}\left[I_x^2-I_{\left(x-1\right)}^2\right]R_x$

for where I.sub.(x-1)<I.sub.FCI.sub.x and where R.sub.x is the small signal resistance R.sub.x=(V.sub.xV.sub.(x-1))/(I.sub.xI.sub.(x-1)). The power delivered to the load is given by

[00026]$P_L=I_{\mathrm{FC}}{V}_{\mathrm{OC}}-P_{\mathrm{loss}}$

whereby P.sub.in=P.sub.L+P.sub.loss=I.sub.FCV.sub.OC or more specifically

[00027]$P_{100}=P_L+P_{\mathrm{loss}}=V_{\mathrm{OC}}{I}_{\mathrm{FC}}+\underset{0}{\overset{n}{.Math.}}\left[I_x^2-I_{\left(x-1\right)}^2\right]R_x$

The efficiency is then given by

[00028]$=\frac{P_L}{P_{\mathrm{in}}}=\frac{P_L}{P_L+P_{\mathrm{loss}}}\frac{V_{\mathrm{OC}}{I}_{\mathrm{FC}}}{V_{\mathrm{OC}}{I}_{\mathrm{FC}}+I_{\mathrm{FC}}^2{R}_{\mathrm{eff}}}=\frac{V_{\mathrm{OC}}}{V_{\mathrm{OC}}+I_{\mathrm{FC}}{R}_{\mathrm{eff}}}$

[1363] To analyze the fuel cell performance, the electrical curves are converted in FIG. 85B by adding current lines I.sub.1, I.sub.2, I.sub.3, I.sub.4, and Is with corresponding data points A.sub.1, A.sub.2, B.sub.2, B.sub.3, C.sub.3, A.sub.4, B.sub.4, C.sub.4, A.sub.5, B.sub.5, and C.sub.5. For simplicities sake, the curves are converted into piecewise linear resistances R.sub.1 through R.sub.5.

[1364] The piecewise linear resistance occurring in the ohmic region of operation may also be considered as have a small signal differential resistance denoted by the lower case variable r.sub.ss where ss means small-signal or differential resistance. Differential resistance r.sub.ss may be considered as the partial derivative of voltage with respect to current for operation V/I within the ohmic operational region irrespective of the polarization voltage V*. Referring to the previous illustration FIG. 8A, differential resistance r.sub.ss may a component of membrane impedance Z.sub.memb 102 which may include various frequency dependent mechanisms, e.g. the relaxation time needed for an ion to bond to an ionomer and then be released, or the average collision time between water and protons in the polymeric matrix, including the formation and dissociation of hydronium ions.

[1365] In FIG. 85C, the curves are converted into straight line segments 580p, 581p ands 582p so that the resistances R.sub.x can easily be estimated from measured data. In the following table power is measured in mW and normalized by area. Note the small resistance may be greater or small than the average DC resistance depending on the membrane and current density. For example at point A3 the average resistance R.sub.FC=3 cm.sup.2 while the small signal resistance r.sub.ss is only 1.2. cm.sup.2. Conversely, around point B5 the differential resistance r.sub.ss=3.5 cm.sup.2 while the average DC resistance is lower, having a value R.sub.FC=1.8 cm.sup.2. In general, for power calculations the DC value is more meaningful while for transient and AC behavior the small signal resistance is more relevant.

TABLE-US-00009 X I.sub.x/A V.sub.x X 1 I.sub.x1/A V.sub.x1 P.sub.in/A R.sub.FC P.sub.L/A P.sub.loss/A r.sub.ss Units: Membrane mA/cm.sup.2 V mA/cm.sup.2 V mW/cm.sup.2 cm.sup.2 mW/cm.sup.2 mW/cm.sup.2 % cm.sup.2 100 m A1 25 0.76 OC 0 0.95 24 7.6 19 5 80 7.6 Nafion A2 50 0.68 A1 25 0.76 48 5.4 34 14 72 3.2 PEM A3 115 0.60 A2 50 0.68 109 3.0 69 40 63 1.2 A4 180 0.50 A3 115 0.60 171 2.5 90 81 53 1.5 A5 200 0.45 A4 180 0.50 190 2.5 90 100 47 2.5 20 m B2 50 0.83 OC 0 0.95 48 2.4 42 6 87 2.4 PFSA-PTFE B3 115 0.79 B2 50 0.83 109 1.4 91 18 83 0.6 CRM PEM B4 180 0.67 B3 115 0.79 171 1.6 121 50 71 1.8 B5 200 0.60 B4 180 0.67 190 1.8 120 70 63 3.5 20 m C2 50 0.93 OC 0 0.95 48 0.4 47 1 98 0.4 Porous C3 115 0.90 C2 50 0.93 109 0.4 104 6 95 0.5 PEM C4 180 0.76 C3 115 0.90 171 1.1 137 34 80 2.2 C5 200 0.69 C4 180 0.76 190 1.3 138 52 73 3.5

[1366] From the above table the superior performance of the fabricated 20 m porous PEM over the 20 m PFSA-PVA-PTFE composite reinforced membrane CRM is confirmed. Both the porous PEM and the CRM significantly outperform conventional 100 m Nafion based membranes. All membranes employed a industry standard homogenous gas diffusion layer. A thorough comparison reveals several key beneficial innovations, namely [1367] The porous membrane exhibits almost no activation losses, i.e. no significant voltage droop in the first 50 mA/cm.sup.2. In contrast Nafion exhibited a 30% drop of 0.27V from 0.95V to 12 0.68V over the same current range. [1368] For a power input of 109 mW/cm.sup.2, nominal operation in the ohmic region, the porous PEM maintained a high cell voltage of 0.9V delivering 104 mW/cm.sup.2 output at a power conversion efficiency of 95% while the Nafion film delivered only 69 mW/cm.sup.2 at a poor efficiency of only 63%. The PFSA CRM membrane outperformed Nafion at an efficiency of 83% with a delivered power of 91 mW/cm.sup.2. [1369] At a higher power input 171 mW/cm.sup.2 in the higher end of the ohmic operating range, the porous membrane maintained an efficiency over 80% delivering 137 mW/cm.sup.2 while Nafion membrane falls to 53% power efficiency and only 90 mW/cm.sup.2 producing almost as a much heat as delivered power. The developed PFSA-PTFE CRM maintained a usable 71% efficiency and 121 mW/cm.sup.2 but not competitive to the porous PEM. [1370] At high input power densities of 190 mW/cm.sup.2 and over, all fuel cell exhibit efficiency loss due to carrier transport mechanisms and water logging. That said, the efficiency of the porous PEM maintained the best performance at 73% power efficiency, the CRM film delivered 63%, and the Nafion film fell to 47%. [1371] Beyond the activation operating region where resistance is not phenomenologically representative of fuel cell physics, the DC specific resistance the Nafion membrane over 109 mW/cm.sup.2 of input power ranged from 2.5-to-3.0 cm.sup.2 while the porous PEM exhibited specific resistances of 0.4-to-1.3 cm.sup.2, representing an 48% to 84% reduction. The CRM maintained a range of 1.4-to-1.8 cm.sup.2, a 40% improvement over conventional fuel cells. [1372] Small signal DC impedance r.sub.ss of the fabricated fuel cells ranged 0.6-to-3.5 cm.sup.2, slightly lower than Nafion in the ohmic range but more resistive at high power densities.

[1373] FIG. 85D illustrates the power output of CRM 600b and porous PEM 600c membranes contrasted against a conventional Nafion based fuel cell 600a graphically as a function of input power illustrating the electrical benefits of membranes fabricated in accordance with this invention.

[1374] Curves 600c, 600b, and 600a further illustrates the improvements in power efficiency q of the new membranes, where =(V.sub.OCV.sub.x)/(I.sub.x) at any point (I.sub.x, V.sub.x) and where V.sub.OC=0.94V. Clearly the porous PEM is capable of delivering significantly higher power outputs and efficiencies than present day fuel cells. The observed improvement in efficiency not only improves fuel cell performance and conserves fuel, it also reduces waste heat dissipated in the fuel cell stack.

[1375] FIG. 85E illustrates measured power loss in a fuel cell as a function of input power density for three different fuel cells, namely Nafion PEM 602a, PFSA-PVA-PTFE composite reinforced membrane CRM 602b, and porous PEM 602c. As shown Nafion 602a dissipates significantly more power than the CRM and porous PEM films made in accordance with this invention. Note that while the lower abscissa and left ordinate axis have units of power density in mW/cm.sup.2, the upper abscissa and right ordinate axis have units of watts for a fuel cell with an active area of 120 cm.sup.2, i.e. where the unit area A.sub.FC=1 cm.sup.2 and where m=120.

[1376] FIG. 85F illustrates the same data sets replotted as the power loss P.sub.loss, i.e. dissipated heat in the fuel cell, as a function of the delivered output power of the fuel cell P.sub.L for Nafion PEM 603a, PFSA-PVA-PTFE composite reinforced membrane CRM 603b, and porous PEM 603c. The left and bottom axis are plotted in units of power density in mW/cm.sup.2 while the right and upper axis are labelled in units of watts for a fuel cell with an exemplary active area of 120 cm.sup.2, i.e. where m=120. The unique data first-of-its-kind representation illustrates that at a certain power density specific to the onset of transport limited conduction losses increase rapidly. While for Nafion PEM 603a this upturn occurs at 90 mW/cm.sup.2, for CRM PEM 603b the onset of transport losses occurs at 120 mW/cm.sup.2 while for porous PEM 603c the threshold improves to 140 mW/cm.sup.2, a power density 50% greater than commercial films. Below the threshold, the porous PEM dissipates significantly less power for the power delivered than the Nafion PEM.

[1377] In general the lossy inflection point roughly corresponds to the current at which peak power delivery occurs. FIG. 86 illustrates power output as a function of PEM current density. The graph contrasts 100 m Nafion PEM 585 against a 20 m CRM 586 and two different 20 m porous PEMscurve 587a describes a film with 1 m pores while curve 587c is for membranes with 100 nm pores. As shown fabricated PEMs all show peaks at current densities around I.sub.FC/A=180 mA/cm.sup.2 with 20 m CRM 586 exhibiting a peak power output +30% above Nafion. As shown, 20 m porous PEMs exhibit a power performance improvement of 43% above Nafion with smaller pore films exhibiting a slight improvement in power density over the larger pore membrane.

[1378] There is no one-to-one correspondence between current density I.sub.FC/A and power density P/A because the fuel cell voltage V.sub.FC is itself a function of current. Using the above table however power and voltage do correlate for each particular film. Specifically at I.sub.FC/A=180 mA/cm.sup.2, a 100 am Nafion PEM 585 exhibits a voltage of 0.5V and a power density at 90 mW/cm.sup.2. At the same current, a 20-m CRM PEM 586 exhibits a voltage of 0.67V and a power density at 121 mW/cm.sup.2 while the fabricated 20-m porous PEMs exhibit a voltage of approximately 0.76V with a corresponding power density at 137 mW/cm.sup.2. The performance of a fuel cell is also however, influenced by the performance of the gas diffusion layers that transport gas to the membrane.

Gas Diffusion Layer Fabrication.

[1379] The gas diffusion layer or GDL performs a number of roles in a PEM based fuel cell including providing (i) electric connection between the bipolar plate (BP) and catalyst layer (CL), (ii) pathways for reactant transport, heat and water removal, (iii) mechanical support for the membrane electrode assembly (MEA), and (iv) protection of the CL from erosion by gas flows or other factors. Physical processes in GDLs include diffusive transport, bypass flow induced by in-plane pressure differentials between neighboring channels, through-plane flow induced by mass sourcing and sinking to catalyst layers, heat transfer, two-phase flow, and electron conductance.

[1380] FIG. 87A illustrates a GDL comprising a GDL comprising a single layer of uniform, i.e. homogenous, material 621u contacting catalyst layer 631 in turn formed on ion exchange membrane IEM 635. Unfortunately, gas diffusion layers using a single homogenous layer of porous material suffer from numerous deficiencies fatal to PEM operation. If the porosity of a uniform GDL is too great a number of adverse effects degrade GDL performance. These adverse effects include a variety of mechanisms including (i) nominal gas pressure levels P.sub.gas will cause excessive gas flow rates in the PEM, (ii) water will accumulate at the CL-GDL interface causing water logging, (iii) reduced contact area between the GDL and the catalyst layer results in high interfacial contact resistance with large ohmic membrane losses, and (iv) electrical performance is overly sensitive to applied pressure causing GDL deformation affecting gas conduction and film conductivity.

[1381] The problem with any uniform material used to form a gas dis diffusion layer is an intrinsic tradeoff between atoms carrying current and the pores in between carrying gasses. Increasing the pore size improves gas flow but increases electrical resistance. Conversely smaller pores increase GDL surface contact area lowering contact resistance and improving the atomic volume of electrical conducting atoms in the GDL matrix, together reducing series resistance through the layer. Unfortunately, smaller pores limit gas transport through the matrix reducing the hydrogen fuel supply arriving at the PEM interface available to sustain necessary redox reactions. Smaller pores also adversely impact the cathode GDL's ability to remove generated water from the cell. Accordingly, a gas diffusion layer of unform porosity represents a significant compromise between gas and water transport versus electrical and thermal conduction. The resulting tradeoff results in IEMs with high electrical resistance, a propensity for water logging and membrane swelling, low cell voltages, and increased sensitivity of fuel cell performance to atmospheric humidity.

[1382] In an attempt to ameliorate this issue, commercial GDLs today generally comprise two layers as shown in FIG. 87Ba thicker uniform macroporous GDL 621u, and a thinner microporous layer or MPL 614 used for interracially managing charge and material transport. The introduction of thin MPL 614 between the gas diffusion layer 621u and the catalyst layer 631 allows for independent control of contact resistance and gas diffusion. Specifically the smaller pore material contacts the catalyst layer to reduce electrical contact resistance to the electrically active catalyst layer while the second thicker GDL layer comprises a sparser atomic matrix contacting the bipolar plate. Because of the preponderance of conductive carbon in both layers, there is essentially no contact potential or interfacial resistance between GDL 621u and MPL 614.

[1383] One immediate benefit of the bilayer GDL is the control of water agglomeration at the interface between the cathode catalyst layer 631 and the gas diffusion layer. Referring to FIG. 88, water transport mechanisms in a hydrogen fuel cell include water generation and condensation within catalyst layer 631 complicated by water transport within IEM membrane 635 involving electroosmosis countered by back diffusion. These competing electrochemical and physical mechanisms are responsible for the complex electrical conductance characteristics of a fuel cell as a function of current density.

[1384] As shown in schematic on the left, in the absence of an microporous layer water transport from the CCM-GDL interface through GDL 621u to the gas channel cathode chamber 613 in cathode bipolar plate BPP 612 involves a convoluted interstitial path 617 referred to as tortuous water transport. Without controlling water diffusion, generated condensed water 610 also agglomerates 611a along the CCM impeding conduction and fuel cell operation. By introducing MPL 614, the water generation rate is controlled by MPL porosity greatly reducing water agglomeration 611x and reducing the propensity for membrane swelling and water logging.

[1385] It should be mentioned, that some publications refer to a macroporous substrate or MPS. This term is less common and somewhat confusing as it presumes a specific fabrication flow, specifically as the term macroporous substrate implies the GDL starting material contain larger pores than other layers within the gas diffusion layer. Care must be taken when examining publications to clarify the lexicology of the specific journal.

[1386] Practically speaking the starting substrate such as carbon paper may comprise larger pores than subsequent layers deposited on it or vice versa just so long that the smaller pore material contacts the CCM and the larger pore side contacts the bipolar plate. In essence the sequence by which the bilayer material is formed is irrelevant so long that it is assembled into MEA5 in the proper orientation. Within this application the term microporous layer (MPL) shall mean GDL layer having smaller pore sizes than other layers in the GDL, irrespective as to whether the MPL was used as a substrate in fabrication, or if it was deposited on another layer.

[1387] Although a bilayer GDL affords added control in balancing water and electric conduction, homogenous gas diffusion layers are far from optimum. In a creative embodiment of this invention, gas diffusion layers made in accordance with this invention comprise a deposited carbon layer that is neither homogenous in chemical composition and stoichiometry, nor uniform in porosity. The term hGDL is used herein to describe multilayer heterogenous gas diffusion layers' structures and to differentiate them from conventional bilayer GDLs having a single uniform deposited layer.

[1388] Fabrication of these next generation GDLs may involve a variety of materials including carbon paper, carbon fiber, carbon cloth, or carbon felt. Carbon is attractive because of its good thermal and electrical conductivity, its permeability to gasses, its low chemical reactivity and immunity to oxidative degradation, and lack of toxicity. Importantly carbon is hydrophobic helping drain condensed water and preventing undesirable edema-like water retention and membrane swelling. Alternative GDL materials may include metal based meshes and porous films but these materials suffer corrosion risks and are generally too hydrophilic for good water clearance.

[1389] Although carbon fiber paper offers superior electrical performance, carbon fiber cloth more easily stretches and deforms to better match the topography of the CCM catalyst layer and the bipolar plate sandwiching the GDL. The rigidity of carbon cloth can be modified and conductivity enhanced by applying additives such as carbon black powder or phenolic resin followed by a high temperature carbonization process. Alternative GDL materials include a polyacrylonitrile (PAN) derived carbon cloth, cellulose, or cotton fibers chemically coated to enhance their conductivity. One material well suited for realizing a porous structure with electrical conductivity is carbon in the form of graphite. Other candidates include carbon fibers, carbon nanotubes, graphene, and various composite materials.

[1390] Another concern is the behavior of a GDL under mechanical pressure. In fuel cell assembly the stack of membranes is compressed to ensure good contact between the conductive elements within the cell. Unfortunately, a sparse carbon matrix is compressible and will deform, allowing the GDL to encroach into the gas channels of the BPP and impeding gas flows. As shown in FIG. 89, applying a fuel cell structure comprising GDL 621, BPP 612, and gas channel 613 shows no deformation or MPL encroachment at a pressure up to 1 megapascal with units MPa. At 2 MPa some deformation 621z encroaches into gas channel 613. At 6 6 MPa however a significant volume of GDL 621z invades the gas channel affecting hydrodynamic flow. The over-compression problem can made in accordance with this invention be reduced by lowering the applied torque on the assembly screws to 3 MPa or by fortifying the GDL mechanically with carbon nanotubes or with polymers such as plastics or PTFE fillers up to 10% by weight.

[1391] Although GDLs can be formed by manually spraying or painting layers onto carbon paper, these methods are not reproducible, manufacturable, or scalable, as pore size depends on deposition rate, processing temperature, and stoichiometric solute concentration. Another challenge to reproducibility is the need to constantly stir carbon paints to maintain mixing and prevent fibers from precipitating out of solution.

[1392] As disclosed herein, one embodiment of this invention able to precisely control film thickness, stoichiometry and porosity of a multilayer carbon film involves the sequential deposition using a multi-head printer depicted schematically in FIG. 90A. In the fabrication sequence shown carbon is deposited onto a starting substrate comprising a premade microporous layer. During processing three sources of carbon 621a, 621b, and 621c offering different degrees of granularity, namely fine, medium, and coarse fibers respectively, are sequentially deposited through separate print heads 625a, 625b, and 625c onto MPL carbon paper 200 as a starting substrate.

[1393] The term MPL is referred to as a micro-porous layer indicating the size of the pores in the paper are smaller than one micron, typically 0.5-to-1.0 m in diameter, smaller than the carbon deposited onto it. In 2D printing the print head must scan back and forth as the carbon MPL paper is fed through the printer in the same manner an inkjet printer works. Alternatively, the print head may comprise a continuous bar or a number of smaller print heads able to uniformly print the entire width of the paper in one pass eliminating the need for scanning the a single print head back and forth across the paper width.

[1394] In the case of linear motion of the carbon paper illustrated in FIG. 90A, the uncoated carbon paper 620 is first coated by spray 626a with the material 621a to produce a deposited layer 621d comprising the least porous layer GDL1. As the paper advances areas already coated by GDL1 are next coated by spray 626b with the material 621b to produce a deposited layer 621e comprising the layer GDL2 of medium porosity. As the paper further advances, areas already coated by GDL2 are next coated by spray 626c with material 621c to producing deposited layer 621f comprising the porous layer GDL3. This final deposited layer 621f, the most coarse and porous of the three, may also be doped with scavenger molecules comprising GDL filler 622f introduced into the ink slurry shown as material 621c.

[1395] In one embodiment, the addition of GDL filler 622f during deposition results in permanent fillers 622x being formed with the printed GDL matrix. The function of the GDL filler is to sequester and degrade carbon monoxide (CO) to protect the CCM catalyst layer such as platinum from poisoning. Mechanistically carbon monoxide scavengers useful as GDL fillers made in accordance with this invention include elements able to oxidize CO into CO.sub.2. These include metal oxides of cerium oxide (CeO.sub.2), iron oxide (Fe.sub.2O.sub.3), manganese oxides such as MnO, calcium titanium oxides including CaTiO.sub.3 aka perovskite oxides, and copper based catalysts such as CuO. Aside from oxides of transition metals (TMs), other physical structures containing TMs may include functionalized carbon nanotubes, metal organic frameworks (MOFs), functionalized graphene substrates, TM nanoclusters, and functionalized polyhedral silsesquioxanes such as POSS and DDSQs. Other catalysts able to oxidize CO when embedded into the carbon matrix of the GDL include gold (Au) nanoparticles, bimetallic compounds such as platinum-tin (PtSn), zeolites, and catalysts of rhodium (Rh) and ruthenium (Ru) in various elemental, compound, and MOF configurations. For example, in ruthenium catalyzed reaction of carbon monoxide to form carbon dioxide, the reaction is given by CO+Ru+/(O.sub.2).fwdarw.CO.sub.2+Ru where the ruthenium is recovered fully with each turn. While the turnover frequency (TOF) for ruthenium (Ru) catalysts in the oxidation of CO to CO.sub.2 varies by temperature and pressure, in general a TOF of several hundred conversions per second is possible.

[1396] Like MOFs, zeolites can be used to complex catalytic transition metals such copper (Cu), iron (Fe), or cobalt (Co) into high temperature catalysts. Zeolites, aluminosilicates with a crystalline structure composed of SiO.sub.4 and AlO.sub.4 tetrahedra linked by shared oxygen atoms offer a variety of advantages to enhance TM performance and longevity in catalysis. Specifically, introducing a transition metal into zeolite allows the metal atom to function as the active reaction site while the inert zeolite framework provide chemical and thermal stability. Moreover, the porous structure of zeolites provides a large surface area, enhancing the adsorption of CO and facilitating the contact between reactants and catalytic sites. Examples of zeolite CO scavengers compatible with used in the inventive include copper zeolite (Cu-ZSM-5) and cobalt zeolite (Co-ZSM-5) where either copper or cobalt have been substituted into the zeolite atomic framework.

[1397] Using any of the scavengers described above, the GDL fillers behave like a microscopic scrubber similar to a catalytic converter in automotive vehicles but on a molecular scale. Although these scavengers may be introduced anywhere within the GDL or MPL substrate, they may also be contained in specific portions of the deposited film to reduce material costs. For example, the permanent filler 622x may be isolated or concentrated within the more coarse GDL3 layer 621f where exposure to incoming airflow is statistically greater than in less porous regions of the carbon matrix such as layer GDL1.

[1398] In another embodiment of this invention, the required mol fraction of filler molecules should scale with the density of the carbon layer containing it. For example, the required density of filler 626x in coarse layer GDL3 621f is lower than that needed in the denser less porous first layer GDL1 621d. By this argument, the filler concentration in MPL 620 should be even higher commensurate to its higher density, which is a disadvantage in having a higher material cost. One advantage of doping the MPL substrate with the scavenger catalyst filler is that the carbon paper can be prefabricated with the catalyst already embedded, thereby eliminated the need to complicate the deposition process by including GDL filler 622f as a solute into the carbon ink material 621c.

[1399] Other non-obvious considerations in the hGDL process involve equilibrating deposition rates to achieve a steady membrane speed during printing especially in continuous print roll-to-roll processes. Since the carbon paper necessarily advances at a steady pace, producing each deposited layer to a specific thickness must account for differences in the formulations of carbon solutions 625a, 625b, and 625c, each with different viscosities and carbon filler sizes. To maintain a constant deposition rate despite varying viscosities, the fluid pressure must be maintained separately for all three nozzles 625a, 625b, and 625c.

[1400] Another variable to be considered is the distance between the print head nozzle and the paper. As more layers are deposited not only does the GDL thickness increase but the gap between the print head and the paper decreases meaning the spot width from spray 626c is smaller than 626a. To maintain a uniform thickness the pressure and flow rate driving the printer head 625c must be greater than head 625b which must be higher than the pressure driving 626a in order to produce similar thickness assuming comparable viscosities. In this manner, carbon growth can be adjusted dynamically producing a pore size increasing from layer GD1 to GDL2 to GDL3. Although the multiple head implementation can produce step changes in porosity the method cannot produce a smooth continuous gradation in pore size.

[1401] In another embodiment, to produce a continuum in pore size made in accordance with this invention requires blending, i.e. mixing 627 different carbon sources and spray them through a common spray nozzle. This sequential blended carbon coating method is shown in FIG. 90B where one print head 625z deposits some blend 626z of fine, medium, and coarse carbon coatings onto MPL carbon paper 620. In this process the print head remains above stationary position along the carbon paper until the full thickness of the GDL 621s is deposited. The layer may comprise discrete boundaries of compositions 621d, 621e, and 621f or may be continuously graded with no clear boundaries except between the deposited layer 621z and the MPL carbon paper 620. Precise deposition rates relies in pressure control 624 of propellant 623. In another embodiment of the invention, the print head nozzle opening 625n comprises a rounded rectangular shape able to facilitate printing of carbon links with longer fibers without clogging. The semi method may also be applied to multi-head carbon printing where the length of the orifice is greater for the longer carbon fiber solutes and smaller for the fine textured printing.

[1402] As depicted in schematic cross section of FIG. 91, the size of the pores are graded from micron sizes at the GDL-to-CCM interface to macropores located at the top of the GDL adjacent to the bipolar layer and gas channels. The submicron pore size of the micropore layer 620 or MPL at the CCM interface maximizes contact area. Atop the MPL is a graded gas diffusion layer of varying pore sizes, For example the carbon paper may comprise a micropore layer 40 m thick with pore sizes of 0.5 m to 1.0 m. The surface area available for ohmic contact to the CCM is approximately 3 50%. Formed atop the MPL is the GDL1 of 120 m thickness containing 10 m pores followed by GDL2 comprising a 120 m thick layer of 20 m pores, covered by GDL3 comprising a 120 m layer with 100 m sized pores. Overall the GDL thickness usually ranges from 100-to-500 m. SEM photographs of fabricated films are included in FIG. 92 including GDL1 shown in SEM 621dd, GDL2 shown in SEM 621ee, and GDL3 shown in SEM 621ff.

[1403] Alternatively the pore size gradation can be more gradual as represented by graded GDL layer 621z shown in FIG. 93. The actual pore dimensions may vary depending on the process but in general the advanced hGDL gas diffusion layer made in accordance with this invention comprises a monotonic increase in density from its MPL base 620 abutting the CCM core to the top of the composite GDL layers abutting bipolar or tripolar plate. Specifically as shown in the illustration MPL layer 620 contacts cathode catalyst layer 631c present on the top of ion exchange membrane 635. The more porous top of composite GDL layers 621z abut bipolar plate 630 and gas channel 631. In one embodiment, the gradation in porosity of the GDL varies monotonically from the dense MPL 620 adjacent to the CCM to a lower fiber density adjacent to the bipolar plate 630.

[1404] While the exemplary cross section depicts the GDL attached onto the anode side of the CCM, i.e. where MPL 620 contacts cathode catalyst layer 631a, a second GDL of similar but not necessarily identical construction is attached on the anode side of the GDL contacting anode catalyst layer 631a. Although the same gas diffusion layer material may be used for both cathode and anode, the construction of the films as disclosed may also differ between the anode and cathode to better match the transported charge and electrochemistry of the redox half cell and whether the reaction at the interface involves oxidation or reduction chemistry.

[1405] The resulting gradient in gas concentrations from varying the film pore size improves gas transport by introducing diffusion assisted transport offsetting some of the impact of the micropore interface. A four zone graded GDL structure although not continuous to be vastly superior to the unform of uniform GDL atop the MPL demonstrated thus far. Five zone, six zone, or continuously graded pores are expected to further enhance fuel cell function and durability.

[1406] Pore size can varied by charging the growth conditions and by changing the length of carbon fibers used in the film growth. In one embodiment the micropore layer is composed of fibers 5-to-10 ms in size while the three GDL layers range from 6 mm up to 14 mm. During deposition, the average length can be adjusted by controlling the blend of mix of the carbon fibers in a continuous process. For example 6 mm fibers are transitioned to 10 mm fibers by decreasing the flow rate of the shorter fiber and gradually increasing the longer fiber content to replace shorter elements.

[1407] In one embodiment of this invention, the average porosity of the GDL on the cathode and anode side of the fuel cell need not be the same. For example, in a hydrogen fuel cell the anode involves ionized hydrogen (proton) transport while in the cathode the reducing agent is either pure gaseous oxygen or filtered air comprising a mix of 78% nitrogen and 21% oxygen not including water vapor which is present in both the FC's anode and cathode. Since the oxygen molecule O.sub.2 is larger than hydrogen molecule H.sub.2 and the proton H.sup.+, on one embodiment of this invention the GDL average porosity on the cathode carrying oxygen is fabricated with larger pores than the GDL used on the cathode.

[1408] Another important embodiment of the gas diffusion layer is to manage moisture in the cell during operation by draining away excess water, especially in the cathode. Water management includes process control of GDL porosity, tortuosity, and pore-size distribution (PSD). Made in accordance with the invention, moisture regulation is primarily controlled by hydrophobicity of the MPL layer and its interface to the catalyst layer, balancing the competing processes of membrane drying and water flooding.

[1409] The material properties may be adjusted by infiltrating using carbon nanotubes into the MPL, introducing NH.sub.4Cl ammonium chloride followed by recrystallization and pyrolysis, adding graphite powder or alternatively blending a small concentration of hydrophobic PTFE, e.g. 10% by weight into the carbon matrix. Alternatively graphene oxide may be employed when fabricating gas diffusion layers where the crystallinity of a carbon matrix is used to adjust its tensile strength and electrical conductivity based on the mix of CO and CO covalent bonds formed between the GO and the carbon fiber. Likewise permanent fillers designed to degrade atmospheric toxins such as CO into nonreactive CO.sub.2 may be included in the cathode GDL for a hydrogen fuel cell but are not required on the anode.

[1410] Note that the term gas diffusion layer is borrowed from the lexicography of hydrogen fuel cells where the reactants including the charge source such as ionized protons and the reducing agents such as oxygen are gaseous. In the case of glucose and hydroxide fuel cells however, charge conduction does not involve a gas but a suspension of cations or anions in solution.

[1411] In an exemplary fabrication sequence as described the GDL is formed on a carbon paper substrate then attached to the catalyst layer of the MEA3 core of the fuel cell. The assembly based process for attaching the GDL to the CCM is discussed later in a related application related application titled Advanced Fuel CellDesign, Apparatus, & Fabrication, referenced herein. The specific sequence, whether connecting the CCM to the anode side or cathode side GDL is not critical nor is the exemplary sequence intended to be limiting. Although the same GDL can be used for both anode and cathode sides of the CCM, in general the gases on the cathode side namely O.sub.2 and H.sub.2O are atomically larger than the H.sub.2 gas feeding than anode. As such, in one embodiment the pore sizes of the cathode size GDL are larger than that on the anode.

[1412] In one embodiment of this invention, the GDL attached to the cathode side of the CCM membrane in an MEAS assembly may include additives such as metal oxides, metal functionalized carbon nanotube, boron nitride nanoparticles, bismuth compounds, and polyhedral silsesquioxanes such as POSS and DDSQs, able to disrupt diffusion of atmospheric contaminants such as nitric oxide (NO) from reaching the CCM from ambient air supplies and poisoning the catalyst, the ionomeric groups, or both. In other words, scavengers preventing damage to the cathode catalyst layer (CCL) need not be limited to the catalyst layer itself but may be integrated into the gas diffusion layer, removing toxins before ever reaching the catalyst layer.

[1413] In another embodiment, a direct methanol fuel cell (DMFC) comprises a heterogenous gas diffusion layer (hGDL) containing permanent GDL fillers embedded within the carbon matrix to remove contaminants present in the methanol before they can reach or damage the CCM. Methanol contaminants may include sulfur compounds, chlorides, and carbon monoxide (CO) all of which can adsorb on platinum, blocking active sites, and degrading catalyst activity in the anode ACL. Permanent fillers added into the anode GDL for DMFC include ruthenium or osmium additives and other transition metals used to break apart contaminants, cerium oxide (CeO.sub.2) acting as a store of oxygen able to oxidize CO.sub.2 and other compounds, and manganese Oxide (MnO.sub.2) useful in capturing sulfur compounds. These permanent GDL fillers help protect the anode's platinum catalyst in a DMFC by either reacting with the contaminants or by providing alternative pathways for oxidation

[1414] In another embodiment of this invention, the MPL side of the GDL can also be coated with an interfacial layer containing a stoichiometric blend of the atomic composition of the GDL and the catalyst layer. The benefit of coating the CCM facing side, i.e. the MPL of the GDL, with an interfacial deposition is to reduce to interfacial states between the GDL and the CCM and in so doing reducing the contact resistance and improving overall fuel cell efficiency. For example, this interfacial layer between the GDL and CCM may comprising a blend of inert PTFE nanoparticles, palladium metal, titanium dioxides, carbon, carbon fibers, graphene, and scavenger metals such as tungsten, nickel, and other transition metals less sensitive to corrosion.

[1415] In an alternative process the thickness of the catalyst layers formed on the ion exchange membrane can be thinned and a second catalyst layer formed on the underside of the GDL. This process, depicted in FIG. 94 is contrasted against a conventional CCM assembly. Specifically in the case of a uncoated hGDL gas diffusion layer comprising graded GDL 621z and MPL 620, the GDL is attached directly onto cathode catalyst KECL 631c. Because they are of dissimilar materials some contact resistance invariably occurs between the two GDL and the CCM. In the case of a catalyst coated GDL shown on the right, a hGDL comprising graded GDL 621z and MPL 620 is coated with catalyst layer 618.

[1416] The catalyst layer can be applied onto the MPL using a decal laminate, attached then annealed to minimize contact resistance. Fabrication of the CCM comprising IEM 635 and catalyst layers 631aa and 631cc can be made using a thinner catalyst layer. If these catalyst layers are sputtered onto IEM 635 all surface states can be eliminated. Beneficially in accordance with this invention, when attaching KECL 618 of the catalyst coated GDL to thin catalyst 631cc, the two materials are similar or identical thereby avoiding all contact resistance between the two elements. In this manner the total interfacial resistance between the hGDL, catalyst layer, and IEM are minimized.

[1417] FIG. 95 illustrates the process flow for fabricating a MEA5 using a catalyst coated heterogenous gas diffusion layer or CC-hGDL. Made in accordance with the previously defined process, in step 650 a frame and skeleton are first molded followed my ionomer fabrication 651 and sputter etch and catalyst depositions 652. In a parallel path fabrication of a heterogeneous gas diffusion layer starts with printing or coating a graded GDL onto a MPL 653, then printing, depositing, or laminating the GDL with a catalyst layer 654 followed by thermal annealing 655 to produce a CL-hGDL. The CCM and CL-hGDL are then bonded 656, annealed, and singulated 667 to complete fabricated MEA6 668.

[1418] In an alternative embodiment the top of the GDL can be coated with a conductive complex such as copper-carbon (CuC) to improve the electrical contact with the bipolar plate. Referring again to the flow chart if FIG. 95, step 659 is optionally included to reduce interfacial contact resistance. The key components of the film ideally will include carbon, copper, and any other metal that might be present in the bipolar plate. The thickness need only be 10 m in order to reduce contact resistance.

PEM+ Electrical Characteristics.

[1419] To isolate the impact of a graded hGDL heterogenous gas diffusion layer on PEM electrical performance, various structures were fabricated, combined with various membranes, and characterized. FIG. 96A illustrates the voltage current characteristics, i.e. the polarization curves of a 100 m Nafion film 580 against four different advanced fuel cells made in accordance with this inventiontwo using a standard bilayer GDL and two using the inventive heterogenous hGDL.

[1420] As shown, all four improved membranes 581, 582c, 583c and 584 significantly outperformed Nafion film 580 exhibiting reduced polarization losses, lower resistance, and lower voltage droop. As measured a 20 m CRM composite reinforced membrane 584 using an innovative PFSA-PVA-PTFE film combined with the hGDL heterogenous gas diffusion layer outperformed the same membrane using a conventional bilayer GDL 581. Similarly the 20 m porous PEM combined with the hGDL heterogenous gas diffusion layer 583c outperformed the same membrane using a conventional bilayer GDL 582c. In other words, the graded hGDL made in accordance with this invention has been experimentally confirmed to outperform the same CCM using conventional GDLs.

[1421] FIG. 96B compares measured fuel cell polarization curves of conventional GDL and graded hGDL refenced against currents I.sub.1/A.sub.FC=25 mA/cm.sup.2; I.sub.2/A.sub.FC=50 mA/cm.sup.2; I.sub.3/A.sub.FC=115 mA/cm.sup.2; I.sub.4/A.sub.FC=185 mA/cm.sup.2; and I.sub.5/A.sub.FC=200 mA/cm.sup.2. Curve 580, the polarization curve for a 100-m Nafion membrane includes data points A1 through A5 with numerically corresponding to the current subscripts.

[1422] Curves 581 and 584 with data points B2-B5 and D2-D5 illustrate polarization curves for 20-m PFSA CRM membrane contrasting conventional GDLs and heterogeneous hGDL. Curves 582c and 583c with data points C2-C5 and E2-E5 illustrate polarization curves for 20-m porous PEM membrane contrasting conventional GDLs and heterogeneous hGDL. The hGDL data are summarized in the table below describing the measured voltage V.sub.x and V.sub.x-1 at two adjacent points, the power input P.sub.in, power output P.sub.L, and power loss P.sub.loss along with the efficiency .sub.FC, the DC resistance R.sub.FC and the differential resistance r.sub.ss.

TABLE-US-00010 X I.sub.x/A V.sub.x X 1 I.sub.x1/A V.sub.x1 P.sub.in/A R.sub.FC P.sub.L/A P.sub.loss/A r.sub.ss Units Membrane mA/cm.sup.2 V mA/cm.sup.2 V mW/cm.sup.2 cm.sup.2 mW/cm.sup.2 mW/cm.sup.2 % cm.sup.2 20 m D2 50 0.89 OC 0 0.95 48 1.2 45 3 94 1.2 PFSA-PTFE D3 115 0.84 D2 50 0.89 109 1.0 97 13 88 0.8 CRM + hGDL D4 180 0.72 D3 115 0.84 171 1.3 130 41 76 1.8 PEM+ D5 200 0.66 D4 180 0.72 190 1.5 132 58 69 3.0 20 m E2 50 0.94 OC 0 0.95 48 0.2 47 1 99 0.2 Porous E3 115 0.93 E2 50 0.94 109 0.2 107 2 98 0.2 hGDL E4 180 0.80 E3 115 0.93 171 0.8 144 27 84 2.0 PEM+ E5 200 0.74 E4 180 0.80 190 1.1 148 42 78 3.0

[1423] From the tabulated polarization curve data, a direct comparison between the heterogenous GDL and a conventional GDL can be made. For example hGDL point D3 has a voltage V.sub.FC=0.84V with a corresponding efficiency .sub.FC=V.sub.FC/V.sub.OC=0.84V/0.94V=89%. By contrast point B3 for a 20-m PFSA CRM membrane described in a previous table, has a voltage V.sub.FC=0.79V with a corresponding efficiency .sub.FC=V.sub.FC/V.sub.OC=0.79V/0.94V=84%, five points lower than the hGDL fuel cell.

[1424] Similarly hGDL point E3 has a voltage V.sub.FC=0.93V with a corresponding efficiency .sub.FC=18 V.sub.FC/V.sub.OC=0.93V/0.94V=99% while point C3, the polarization curve for a 20-m PEM CRM membrane at the same current density has a voltage V.sub.FC=0.90V with a corresponding efficiency .sub.FC=V.sub.FC/V.sub.OC=0.90V/0.94V=96%, three points lower than the hGDL fuel cell. The combination of the advanced membrane fabrication technologies together with heterogenous gas diffusion layer for convenience sake are referred to herein as PEM+ membrane.

[1425] In order to extract component resistances, FIG. 96C illustrates measured polarization curves converted into piecewise linear segments having differential resistances r.sub.ss approximated by each segment's two end points and a DC resistance R.sub.FC=V.sub.x/I.sub.x determined by the curve's endpoint) I.sub.x, V.sub.x). These piecewise linearized representations include 100-m Nafion curve 580p, the 20-m PFSA CRM PEM+ curves 581p and 584p, and the 20-m porous PEM+ curves 582p and 583p.

[1426] From the foregoing measurements, the fabricated 20-m CRM composite reinforced membrane comprising a PFSA-PVA-PTFE ionomer when combined with the graded hGDL heterogenous gas diffusion layer into a MEA5 showed an increase in power output and a reduction in membrane resistance compared to that of the same PEM membrane using a conventional bilayer GDL. Specifically, the conventional GDL MEA5 shown by curve 581p described in a previously reported table exhibited specific DC resistances R.sub.FC ranging from 2.4-to-1.4 cm.sup.2 while the PEM+ version of the same membrane shown by curve 584p exhibited DC R.sub.FC values of 1.5-to-1.0 cm.sup.2. Small signal resistances were non-monotonic, and similar to one another across the ohmic region of operation.

[1427] At every current density, the MEA5 based on the PEM+ membrane outperforms the conventional GDL. Small signal impedances of the CRM based PEM+ were slightly better than the conventional GDL device, in some cases being half the resistance but in other condition conditions being only comparable. The primary difference in these curves occurs at low currents corresponding to differences in activation energy. Small signal resistances in the ohmic region were more comparable.

[1428] Improvements demonstrated by curve 583p for the porous PEM+ membrane curves 585p are more substantial, varying from an extremely low 0.2 cm.sup.2 at low currents to only 1.1 cm.sup.2 at mA/cm.sup.2 current densities. In contrast the porous membrane with a conventional GDL shown by curve 582p exhibits 0.4 cm.sup.2 at lower currents, double the resistance of its PEM+ counterpart, and exhibited 1.3 cm.sup.2 at 200 mA/cm.sup.2 current densities, a 20% higher resistance than PEM+. Small signal impedance were also halved at low currents using the PEM+ MEA5 construction.

[1429] The reduced losses of the PEM+ MEA5 made in accordance with invention translates directly into an increase in delivered power for a specific input power, an increase in fuel cell power efficiency, and a reduction in waste heat generation. FIG. 96D illustrates a comparison of PEM and PEM+ based MEA5s. As shown, by combining a 20-m porous ionomer with a heterogenous GDL the power output of PEM+ assembly 600e outperforms all other devices delivering nearly 150 mW/cm.sup.2 from a 190 mW/cm.sup.2 electrochemical input. In rank order of power output, porous PEM+ 600e delivers more power output than its conventional GD counterpart 660c. Combining PFSA-PVA-PTFE CRM with the disclosed hGDL, the power output of CRM-based PEM+ assembly 600d exceeds the output of comparable CRM-based PEM 600b but does not exceed the performance of either porous PEM implementation. The 100-m Nafion PEM underperforms all the other combinations.

[1430] Power efficiency , the ratio of power output over power input is shown for various MEA5 assemblies in FIG. 96E. Of the combinations shown, 100-m Nafion PEM 601a exhibits the lowest efficiency with only 47%. In contrast the fabricated 20-m CRM PEM efficiency using a conventional GDL 601b are at 63% and for a graded GDL 601d are at 69%. At 73% efficiency for a conventional GDL and at 78% efficiency using a hGDL, the performance of the porous PEM constructions outperform all other combinations. This benefits translates into lower fuel usage impacting driving range or power backup time, and less waste heat generation impacting fuel cell and system design factors.

[1431] In FIG. 96F, a graph of power loss illustrates that in order of unwanted heat dissipation 100-m Nafion PEM 602a is the worst dissipating 100 mW/cm.sup.2 at a current density of 200 mA/cm.sup.2 while porous PEM and PEM+ membranes shown by curves 602c and 602e dissipate the least heat at 52 mW/cm.sup.2 and 42 mW/cm.sup.2 respectively representing a 48%-to-58% reduction is generated waste heat. PFSA-PVA-PTFE composite reinforced membranes (CRM) offer intermediate improvements at 200 mA/cm.sup.2 with power dissipation densities of 70 mW/cm.sup.2 for a conventional GDL and 58 mW/cm.sup.2 for a hGDL.

[1432] In real world applications, at 200 mA/cm.sup.2 a m=120 fuel cell delivers 24A. At this current, the power loss in 120 cm.sup.2 fuel cell depends on the technology employed. For example curve 602a for a 100 m Nafion membrane with a conventional bilayer GDL dissipates 12 W of power as heat, a PEM+ membrane and hGDL assembly shown by curves 602e dissipates only P.sub.loss=(42 mW/cm.sup.2)(120 cm.sup.2)=5 W in total representing a 60% overall reduction in heat generation. All intermediate implementations including those shown by the power dissipation curves 602b, 602d, and 602c are bounded by the two extremes.

[1433] Identical to the graph of FIG. 85F but for the hGDL devices, the transfer characteristics of power output as a function of electrochemical power input for a fuel cell are shown in FIG. 96G. The graph comprises power loss as a function of power output for a variety of PEM and PEM+ based fuel cells including Nafion PEM-based MEA5 employing a conventional bilayer GDL 603a; CRM based MEA5s employing a CRM and conventional bilayer GDL comprising 603b and 603d curves respectively; and based MEA5s employing a porous PEM with heterogenous hGDL comprising 603c and 603e curves respectively. As an example, a 100 m thick Nafion film using a conventional GDL dissipates 12 W to deliver only 11 W of load power as depicted by curve 603a. Alternatively CRM can deliver 14 W as per curve 603b without a hGDL; 15.5 W as per curve 603d with a hGDL; 16.3 W as per curve 603c without a hGDL; and 17 W as per PEM+ curve 603e with a hGDL based porous membrane. Delivering 17 W to a load at 5 W power loss using the PEM+ membrane and assembly is significantly beneficial compared to 12 W dissipated delivering 11 W as per curve 603a.

[1434] FIG. 97 illustrates power output as a function of PEM current density. The graph contrasts the power output of 100 m Nafion PEM 585 against various four different 20 m films comprising CRM PEM 586, CRM PEM+ with hGDL 588, porous PEM+ with conventional GDL 587c, and porous PEM+ with hGDL 589. Compared to Nafion PEM 585, the power delivered by the various membranes and MEA5 assemblies increase power densities by +30%, +37%, +42%, and +52% respectively. This means the power dissipation in a fuel cell can be reduced by half using embodiments of the invention disclosed herein.

MEA7 Assembly.

[1435] After singulation, individual five-layer MEA5s made in accordance with this invention are assembled into a fuel cell stack with intervening tripolar plates to form a seven layer MEA7 790as depicted in FIG. 98. As shown, each seven-layer MEA7 890 includes a three-layer MEA3 core 893 or CCM. In one exemplary embodiment the thickness Y.sub.CCM of CCM is 50 m. The MEA3 cores are sandwiched by an anode gas diffusion layer 892s and a cathode gas diffusion layer 892c. On one embodiment the gas diffusion layers comprise heterogenous material with multi-layer or graded porosity deposited on a thin MPL thereby forming a hGDL.

[1436] In one exemplary hGDL, the total thicknesses Y.sub.GDLa and Y.sub.GDLc are each 350 m. The MEA5 assembly is sandwiched between two TPP tripolar plates 891. In one exemplary version the tripolar plates 891 are comprised of graphite or composite materials with a total thickness Y.sub.TPP of 450 m. The resulting thickness Y.sub.MEA7 of the exemplary seven-layer MEA7 assembly is 1.2 mm.

[1437] Implemented using the exemplary MEA7 design FIG. 99 illustrates a sixty-layer 24V fuel cell stack 896 of 72 mm and a ten-layer 4V fuel cell stack 897 of 12 mm height contrasted against the height 700 mm tall 21700 lithium ion cell 898. In comparison a conventional 24V fuel cell 895 with steel bipolar plates has a stack height of 373 mm, over five times thicker than the fuel cell made in accordance with this invention.

[1438] In addition to reducing height of the fuel cell stack, the thin graphite tripolar plates offer reduced electrical resistance, improved thermal conduction, and unlike steel plates are corrosion resistant. As shown in FIG. 100, in addition to cathode and anode gas channels 876 and 875 respectively, tripolar plate 891 includes a small compartment 878 located on the exterior edge of the TPP positioned closer to the cathode surface. In one embodiment of this invention a temperature sensor such as a thermistor or semiconductor temp sense IC is inserted into the enclosure and secured by adhesive. The temperature sensor can be used to monitor the heat generated in the fuel cell by providing real time temperature monitoring 879s. Temperature in the fuel cell is affected by cathode air flow and coolant circulation as well as thermal conduction into the backplane holding the iBFC modules.

[1439] Alternatively the in situ temperature sensor may be used for active cooling in conjunction with dynamic temperature control circuit 879c as shown in FIG. 101. In this case, temperature control 879c adjusts operation of heat exchanger 874 to regulate the fuel cell temperature in iBFC 870. It also controls air circulation in the cathode iBFC 870 fuel cell by regulating blower 873. Cathode air flow affects the fuel cell operation as well as providing added cooling. Although hydrogen 871 also flows into 870 and the unused gas is recirculated, hydrogen flow is pressure and flow rate regulated 872 for proper fuel cell operation, not for temperature.

[1440] Power dissipation is a fuel cell depends on the heat generation in the membrane and in the ability of a bipolar or tripolar plate to remove the generated heat. Although many variables must be considered to correlate thermal impedance where =(P.sub.Q/T) to design and operating conditions of a fuel cell the general trend comprises a monotonic inverse, i.e. hyperbolic relationship 900 as depicted in FIG. 102A for a 48 W source using low thermal conductivity materials. Notice for a 48 W fuel cell, the curve indicates a minimal air flow rate of 2.2 m/s to maintain an 80 C. maximum membrane temperature in a 25 C. ambient. As such, a 3 m/s minimum FR flow rate for air cooling is recommended for reliable operation.

[1441] In contrast the table below includes reported values of airflow rate, heat generation, and measured peak temperature for higher conductivity materials. According to studies, thermal resistance ranges from 0.9-to-1.3 C./W for airflow rates over 1.4 m/s represented by points 901a and 901b and from 1.6-to-1.8 C./W at lower flow rates shown by points 902, 903a, and 903b. This thermal impedance does not include the benefit of the low stack height of a stack and thin bipolar plates.

[1442] Overlaying the two data sets in FIG. 102B, using poor thermal conductivity materials causes higher temperatures irrespective of air flow rates. It also provides an estimate of the worst case thermal resistance useful as an upper bound in the design of air cooled fuel cells. Notice that the ratio P.sub.Q/AF of dissipated power P.sub.Q to the air flow velocity AF does not correlate well with the observed thermal resistance . This poor correlation highlights the fact thermal resistance and power dissipating capability of a fuel cell includes both convection and conduction both of which vary with temperature, air flow, surface area, and hydrodynamics, i.e. the formation of convective cells involving viscous or laminar flow. In general, thermal conduction carries 5% to 15% of the heat removed with the remainder involving thermal convention, either forced convention or natural convention. Convective cooling depends heavily on design.

[1443] The two most important design parameters to maximize convective cooling is surface area and airflow. If the surface area of a heat source is too small there is inadequate atoms involved in the heat exchange process whereby cooling will be limited and the resulting thermal resistance will be high. Conversely if the air is still atop a convective surface heat exchange will also be limited. Air removal of heat can occur in two ways, through self convection forming local loops of heat transfer and forced air convection where a fan or blower maintain a continuous supply of cool air to absorb generated heat. Both self convection and forced air cooling require adequate space above the heat dissipating surface for air to flow. If the gap between a heat source and enclosure is too tight air flow will be impeded an excessive heating will result.

TABLE-US-00011 Air Flow (m/s) P.sub.Q Heat (W) P.sub.Q/AF Temp T ( C.) Temp Rise T ( C.) Thermal ( C./W) 2.19 37.7 17 65 40 1.06 1.76 55.7 32 76 51 0.92 1.63 27.6 17 61 36 1.30 1.45 29.1 20 67 42 1.44 0.95 6.3 7 35 10 1.59 0.94 13.7 15 50 25 1.82 Data extracted from Thermal analysis of air-cooled PEM fuel cells, Intl J H.sub.2 Energy Dec 20212.

[1444] Applying the foregoing criteria to a n=8 m=120, i.e. 8s120p fuel cell design means for each cell in the stack P.sub.FC=P.sub.Qmax/n=48 W/8 6 W. Comparing this maximum P.sub.FC power to the power loss to power output curves of FIG. 103 shows the 6 W limit 905 corresponding to a power loss density of 50 mW/cm.sup.2. As shown by curve 603e, a PEM+fuel cell comprising a porous membrane plus a hGDL heterogenous gas diffusion layer is able to deliver 150 mW/cm.sup.2 or 18 W per cell without exceeding the air-cooled 6 W thermal limit of 50 mW/cm.sup.2.

[1445] Similarly curve 603d illustrates the slightly lower performance of a PEM+fuel cell comprising a CRM composite reinforced membrane with a hGDL heterogenous gas diffusion layer is able to deliver 130 mW/cm.sup.2 or 15.6 W per cell without exceeding the air-cooled 6 W thermal dissipation limit per cell, a 13% reduction in power capability compared to the porous PEM+film.

[1446] In dramatic contrast, Nafion PEM curve 603a confirm the 6 W/cell air cooled dissipation limit occurs at a power output of 75 mW/cm.sup.2 or only 9 W/cell, a 50% reduction in air-cooled power delivery capability compared to the porous PEM+ membrane and a 42% reduction in output power compared to a CRM PEM+ membrane. FIG. 103 also overlays the 48 W, 50 mW/cm.sup.2 air cooled thermal limit onto the graph of power loss versus power output The total converted power input per cell equals the sum of the output power and power loss. Specifically, the Nafion PEM delivers 9 W from a 15 W input at 60% efficiency, the CRM PEM+delivers 15.6 W from a 21.6 W at 72% efficiency, and the porous PEM+delivers 18 W from 24 W at 75%.

TABLE-US-00012 Parameter P.sub.out/A P.sub.loss/A mA.sub.FC I.sub.FC P.sub.out P.sub.loss n V.sub.FCmin P.sub.out P.sub.loss Units mW/cm.sup.2 mW/cm.sup.2 cm.sup.2 A W/cell W/cell ns V W/stack W/stack Porous 150 50 120 24 18 6 6 0.58 108 36 PEM+ 8 0.44 144 48 10 0.35 144 48 CRM 130 50 120 24 15.6 6 6 0.58 94 36 PEM+ 8 0.44 125 48 10 0.35 125 48 Nafion 75 50 120 24 9 6 6 0.58 54 36 PEM 8 0.44 72 48 10 0.35 90 48

[1447] Assuming that the fuel cell stack must output a voltage at least 3.5V then for a n=8 stack, the condition can be met for fuel cell voltages V.sub.FC0.44V. According to the aforementioned thermal analysis, power loss is limited to 48 W for the fuel cell stack or 6 W per MEA7 cell. In this way a n=6 stack at the same power density thereby dissipates 36 W. A fuel cell stack where n=10, the power loss should be 60 W for liquid cooled cells. If air cooling is employed, the power remains limited to 48 W or 4.8 W per cell, not 6 W.

[1448] When direct thermal conduction into a temperature regulated backplane is included the thermal resistance is dramatically improved. For example a 120 cm.sup.2 fuel cell comprising a 12-layer stack with a 450-m thick graphite bipolar plate and a total per layer thickness of 1.2 mm has a net thickness of 14.5 mm. The corresponding thermal resistance of a single layer is 0.014 C./W. For a 12-layer stack the thermal impedance increases to .sub.FC=0.17 C./W, a value one-order-of-magnitude lower than air cooling. Assuming a T.sub.FC(max)=85 C. and a backplane temperature T.sub.bp=25 C., with a T.sub.FC=60 C. corresponding to P.sub.FC=T.sub.FC/.sub.FC=(60 C.)/(0.17 C./W)=352 W, a value triple the best case air cooling example.

IEM Membrane Fabrication.

[1449] The previous sections exemplify the formation and operation of homogeneous of PFSA and heterogenous composite reinforced membranes of a PFSA coated film of PTFE. Although these films are representative of ionomers useful in cation conducting fuel cells and electrolysis they are by no means intended to be limiting in beneficial features of the improved ion exchange membranes (IEMs) made in accordance with this invention.

[1450] In general, all ion exchange membranes suffer an intrinsic tradeoff between structural rigidity and electrical conductivity. The more conductive a film is, the weaker the mechanical support of the membrane becomes. Film conductivity may be improved by (i) thinning the membrane thickness, (ii) increasing the density of pendants to increase the molar concentration of ionomers in the matrix, (iii) increasing the hydrophilicity of the material to enhance water-carrier transport, and/or (iv) increasing the porosity of the membrane. In every case described, the mechanical strength of the film is compromised by replacing stronger hydrophobic backbone polymeric chains with weaker electrically active pendants.

[1451] The resulting weaker polymeric matrix adversely impacts the process of membrane fabrication and complicates the handling of films in the assembly of fuel cells or electrolysis units in order to avoid damaging the membrane. A thinner or weaker membrane also adversely impacts film durability, environmental resilience to temperature and humidity cycling, and operational longevity, i.e. membrane reliability. In particular, weaker film are more easily damaged during humidity cycling, power cycling, or a combination thereof.

[1452] In humidity cycling the IEM is subjected to operation during alternating cycles of low humidity, i.e. arid conditions, and high humidity. During humidity cycling water retention causes a mechanically unsupported film to swell like a sponge. During drying out periods, the film contracts causing stress on the hydrophobic backbone of the film. After numerous cycles, cracks appear in the molecular fabric of the film leading to membrane failure and leakages of gas and charges through the damage zones. Eventually the film fails altogether.

[1453] In power cycling, the IEM is operated in repeated cycles conducting high current density and low current density. At high power conditions, generated heat causes expansion of the center portions of a fuel cell stack aggravated by excess water produced in regions of high current density. Differential temperature coefficients of expansion among the various elements within a fuel cell, e.g. the CCM, GDL, bipolar and tripolar plates, and fuel cell stack end caps, result in film stresses on the membrane. Such cyclic operation can cause stress fractures in the polymer leading to immediate or latent failures. The combination of the humidity cycling and power cycling further exacerbates the problem by repeatedly subjecting the film to simultaneous high current densities at high humidity levels followed by cycles of cold arid conditions. The only means to overcome these intrinsic deficiencies of an ion exchange membrane is by improving the strength and durability of the film by reengineering its design.

[1454] Although the film and its mechanical elasticity properties are specific to the chemistry of the ion exchange membrane several key inventive features of an improved IEM made in accordance with this invention apply to all film compositions. These embodiments comprise the following: [1455] A structural endoskeleton made in accordance with this invention forming a grid-like network throughout the membrane laterally providing mechanical support to the more fragile or thinner electrically-active ionomer film, and limiting swelling and shrinkage of the membrane from humidity cycling or during operation thereby improving film stability, reliability and cycle life. [1456] A mechanism to control the microporosity of the IEM without fundamentally changing the chemistry of the resulting matrix. Made in accordance with this invention, the method may include temporarily introducing a soluble filler such as sugar during film polymerization and then removing the sacrificial filler with a solvent such as water after the film polymer is formed or cured. As such, sacrificial fillers comprising a large molecule present during membrane formation and subsequently removed increase film porosity by reducing the density and crystallinity of the membrane as made. Increased porosity enhances charge transport and ionomer conductivity. Conversely, permanent fillers are molecules introduced during casting or subsequent to molding that remain in place after fabrication. Unlike sacrificial fillers which are exclusively intended to increase film porosity by creating more channels within the matrix, permanent fillers can either increase or decrease membrane porosity. Specifically, permanent fillers that disrupt the periodicity, regularity, and crystallinity of a polymer during molding cause defective regions of amorphous material to be formed. These low-density amorphous defect regions exhibit higher permeability than their higher-density crystalline counterparts, and therefore enhance proton transport and conductance. Examples include the introduction of porous silica, alumina, silicates, graphene oxides, perfluoro-dimethyldioxole (PDD); or poly(perfluoro-methylene-methyl-dioxolane) (PFMMD) into the monomer blend prior to casting. Alternatively, post mold processing of a membrane by the selective application of coatings or molecular glues like PVA clog pores present after molding, reducing the channels into the membrane electrolyte. In so doing the permanent filler reduces film porosity, beneficially limiting oxygen back diffusion and fuel crossover, especially important to prevent methanol diffusion in a DMFC. [1457] Molecular glue comprising alcohols or solvents such as PVA where in heterogenous films the glue functions as an chemical intermediary between molecules incompatible for direct bonding. Made in accordance with this invention, examples include solvents able to bond hydrophobic and hydrophilic materials together either between dissimilar elements within a CMR composite reinforced membrane such as a PFSA-PTFE film or at the interface between the ionomer film and the IEM's endoskeleton. [1458] Nanocoating covering the ionomeric membrane forming an interfacial layer between the membrane and the catalyst layer. Made in accordance with this invention a nanocoating may reduce the influence of dangling bonds and interfacial charge states on film conduction, enhance catalytic activity, control CCM porosity and gas transport while minimizing oxygen back diffusion and fuel crossover. The coating can also mitigate the adverse impact of atmospheric contaminants such as carbon monoxide by gettering airborne gasses and particulates which otherwise may disable or poison CCM catalysts. The nanocoating may comprise chemical components present in the catalyst layer and in lower concentrations, chemical constituents of the ion exchange membrane. Alternatively the catalyst and nanocoating can be merged into a single heterogenous layer. [1459] Fillers & Dopants Aside from sacrificial and permanent fillers described above; fillers and dopants made in accordance with this invention comprise carbon fillers such as functionalized carbon nanotubes (CNTs) and graphene oxides (GO); oxide fillers such as silica and metal oxides; polyhedral oligomeric silsesquioxanes fillers such as POSS and DDSQ; nanostructures comprising nanoparticles, nanoclusters, and nanofibers; fillers of metal oxide frameworks (MOFs) comprising ionomers, catalyst and scavenger metals and guests; along with solid acids and proton ionic liquids (PIL).

[1460] In the context of fuel cells, the last bulleted item Fillers and Dopants' describes processes that change the function of an ionomeric polymers. In chemistry, the term filler as defined by Wikipedia particles added to resin or binders (plastics, composites, concrete) that can improve specific properties, make the product cheaper, or a mixture of both. The two largest segments for filler material use is elastomers and plastics. Similarly, Wikipedia defines dopant as a small amount of a substance added to a material to alter its physical properties, such as electrical or optical properties. A variety of permanent fillers are described here below:

Carbon Fillers.

[1461] Examples of functionalized carbon include carbon nanotubes (CNTs) coated with sulfonic acid (SO.sub.3H), carboxyl groups (COOH), hydroxy-phosphorus (POH), amino groups (NH.sub.2), silica (SiO.sub.2), and titania (TiO.sub.2). Examples of functionalized graphene oxides (GO) include polybenzimidazole grafted graphene oxide (ABPBI-GO), sulfonated polysulfone functionalized polymer graphene oxide (FPGO-sPSf, FPGO-sPSU), and perfluoropolyether grafted graphene oxide (PFPE-GO).

Oxide Fillers.

[1462] Oxide fillers comprise inorganic and metallic oxides and complexes thereof. Examples of silica and silicates include silica (SiO.sub.2), alumina-silica zeolite ((Al.sub.2O.sub.3).sub.x.Math.(SiO.sub.2).sub.y) and mordenite, sulfonated zeolite, nesosilicates ((SiO.sub.4).sup.4), silica mesostructured cellular foam (silica MCF), phosphorylated hollow mesoporous silica (HMS-PA), sulfonated hollow mesoporous silica (MCF-SA), or amino or sulfonated hollow mesoporous silica bonded onto a sulfonated polyether ether sulfone polymer (sPEES-MCF-NH.sub.2, sPEES-MCF-SA).

[1463] Examples of metal oxides and inorganic metal frameworks include bismuth molybdate (Bi.sub.2MoO.sub.6), Al-grafted mesoporous silica (MCF-ionomer), poly(m-phenylene-bibenzimidazole) doped mesoporous silica cellular foam (mPBI-MCF), zirconium-dopamine composites and intercalant zirconium with OH, O and X termini. Other inorganic metal oxide include clusters of phosphotungstic acid treated silica (PWA-SiO.sub.2).

Oligomeric Silsesquioxanes Fillers.

[1464] Examples of functionalized polyhedral oligomeric silsesquioxanes (POSS) include thiol coated POSS-SH, phosphoric POSS-S-PA, polyethylene glycol POSS-PEG, isobutyl POSS-iBu, vinyl POSS-Vi, chlorobutane POSS-8Cl, octakis(dimethylsilyloxy) Ot-POSS, octavinyl OV-POSS, octaphenyl OP-POSS, isobutyl-vinyl POSS-iBu-Vi, isobutyl-butylamine POSS-iBu-NH.sub.2, isobutyl-CI POSS-iBu-CI, isobutyl-hydroxide POSS-iBu-3OH, isobutyl-styryl POSS-iBu-styryl, isobutyl-polystyrene POSS-iBu-PS and for generic radicals R the styryl and polystyrene forms POSS-R-styryl and POSS-RPS.

[1465] Other functionalized versions include cyclopentyl-polystyrene POSS-Cp-PS, cyclohexyl-polystyrene POSS-Cy-PS, aminopropylisobutyl POSS-AmNH.sub.2, mercaptopropyl-isobutyl POSS-SH, and mono-(acryloisobutyl) POSS-A. Structural variants of oligomeric silsesquioxanes include double-decker topographies DDSQ functionalized in non-methylated and methylated forms NMe DDSQ and Me DDSQ, with optional functional groups including vinyl, methylpropyl, methyltrichlorosilane, dichloromethylvinylsilane, stereo vinyl, allyloxytrimethylsilane, propyl glycidyl ether, bromostyrene, and acetoxystyrene.

Nanostructure Fillers.

[1466] Examples of nanostructure fillers include nanoparticles, nanospheres, nanoclusters, and nanofibers. Nanostructures include sulfonated poly(methyl methacrylate) nanospheres (sPMMA NS) and porous nanospheres, poly methyl methacrylate sulfonated zinc nanoclusters (PMMA ZnS NCs). Nanosphere functionalized carbon nanotubes combine the structural stability of single and multi-walled CNTs with the catalytic and ionomeric activity of functionalized nanospheres. Example include platinum-amino and titanium-amino functionalized nanoparticle coated carbon nanotubes PtNH.sub.2 NP-CNT and TiNH.sub.2 NP-CNT as well as phosphorated titania carbon nanotubes PO.sub.4TiO.sub.2 CNTs.

[1467] Made in accordance with this invention, nanofibers produced by electrospinning followed by crushing to control fiber length and porosity include poly sulfonated polystyrene nanofibers (sPS). Silver nanoparticles (Ag-NPs) may also be attached to a titanium-dopamine matrix using a sol-gel process. Other nanostructures include zirconium nanosphere Zr NS, also based on a polydopamine scaffold, and MoW nanoparticles derived from phosphotungstic acid. Alumina-silica zeolite ((Al.sub.2O.sub.3).sub.x.Math.(SiO.sub.2).sub.y) nanoparticles may be loaded with metal catalysts. Another class of nanostructure filler as described comprises platinum titanium dioxide nanoparticles (Pt-TiO.sub.2 NPs).

Metal Organic Frameworks (MOFs).

[1468] Examples of metal organic frameworks (MOFs) include convex, cluster, concave, rectangular array, trapezoidal, reflected trapezoidal, hexagonal drum, and octahedral drum geometries with functional sidechains and guest molecules. Other less periodic geometries include zinc-oxide hexaphosphate ester-based metal-organic frameworks and related chemistries. Metals may include elemental atomic titanium, platinum and palladium or metal complexes of zirconium(IV) chloride, zinc acetate, sulfonic ferrous or chromium terephthalate metal clusters. Made in accordance with the invention scavenger metals including lower-cost iron, cobalt and nickel provide catalyst protection from toxins such as NO may be substituted for catalyst metals on the MOF frame, attached to the organic ligands, or bound to a guest molecule.

[1469] Heterogenous metal organic bonds between catalyst and scavenger metal requires inventive organic ligands not used in conventional MOFs. They include dithiolene, ethanedithiol, pyridoxal-thiosemicarbazone, bis(diphenylphosphino)ethane, Schiff base, imidazophenanthroline carboxylate, ethylenediamine, salicylaldehyde, succinate, bidentate phosphine, and bipyridine. A organic alternative to MOF fillers includes triazole grafts onto the polymer's mainchain such as poly(oxy-diphenylether-bibenzimidazole) (OPBI-TG). A special category of metal frameworkzeolitic imidazolate frameworks aka ZIFs comprises tetrahedrally coordinated transition metal ions such as Zn, Co, or Cu bridged by imidazole or imidazolate type linkers (Im).

Solid Acid Fillers & PILs.

[1470] Examples of solid acids include the organic acids such as carboxylic acids (e.g. trimesic acid), oxalic acid, tartaric acid, citric acid, ascorbic acid, and maleic acid and the inorganic sulphamic acid. Being crystalline at room temperature, the acids do not leak nor rearrange the membrane matrix during power cycling. For example bismuth trimesic acid (BiTMA) can be incorporated into a membrane to enhance conductivity without compromising film durability.

[1471] Alternatively polymers can be doped with ionic liquids as a dopant. An ionic liquid is a salt in its liquid state at ambient conditions. General agreement defines an ionic liquid as a salt with a melting point below 100 C. at normal pressures. Unlike most liquids such as water, alcohols, and fossil fuels that are electrically neutral covalently bonded molecules even in their liquid state, ionic liquids are primary made of ions and therefore more chemically reactive and electrically conductive than their covalent counterparts. Ionic liquids (ILs), aka liquid electrolytes or ionic fluids, alter the conductivity of ionomeric membranes.

[1472] ILs come in two formscation ionic liquids and anion ionic liquids. Cation ionic liquids or CILs are derived from salts comprising methylimidazole, imidazolium, pyridine, and quaternary ammonia. Anion ion liquids or AILs are derived from tetrafluoroborate, hexafluorophosphate, bis-trifluoromethanesulfonimide, trifluoromethanesulfonate, dicyanamide, hydrogen sulphate, ethyl sulphate, and butyl-methylimidazolium tetrachloroferrate. A special form of ionic liquid is a protic ion liquid (PIL) comprising a mix of acid and base capable of reversible reaction involving proton (H.sup.+) exchange. In conjugate acid-base reactions, when an acid donates a proton it leaves behind a less positively charged conjugate base. As a coupled reaction, when the base receives the proton becomes a more positively charged conjugate acid. This acid-base reaction differs from simple redox reactions where ionization involves only the transfer of electrons.

[1473] PILs adaptable for use ionomeric polymers and fuel cells include alkyl imidazolium bis-(trifluoromethylsulfonyl)imide ILs. Similarly, polymer ionic liquids aka poly-ILs comprise polymerizable functional groups such as vinyl or allyl groups with repeated monomeric units connected via a polymeric backbone. In operation ILs can enhance the efficiency of the oxidation reduction reaction (ORR) in the cathode of a PEM hydrogen fuel cell increasing conductance and reducing catalyst aging.

IEM Summary.

[1474] Made in accordance with this invention, an ion exchange membrane incorporating fillers and dopants including any of the above enumerated inventive features of carbon fillers, oxide fillers, POS fillers, nanostructure fillers, MOF fillers, and solid acid fillers and PIL dopants; or combinations thereof enable a myriad of potential performance improvements in ionomeric polymers. These innovations can be used separately or in combination. Because the chemical processes used to fabricate two different polymers are often times mutually incompatible or unable to form chemical bonds, the inventive combinations discussed herein are not obvious.

[1475] Aside from the described membrane chemistry, other processes and apparatus made in accordance with the invention to produce a fuel cell's seven-layer membrane electrode assembly (MEA7) include fabrication of an endoskeleton, control of IEM microporosity, and polymer bonding as described in the subsequent sections.

Endoskeleton.

[1476] By providing a endoskeletal grid surrounding panes of ionomer the ionomer cannot swelling laterally within the plane of the film. Furthermore, because the membrane remains compressed from iso-planar pressure of the endoskeleton, then vertical displacement from membrane swelling is also constrained. If the molecular matrix cannot swell, then there is simply no excess compartments in which water can agglomerate during operation. In this manner the endoskeleton provides mechanical regulation of water content within the film independent of the membrane's polymer chemistry. Various methods to reproducibly form endoskeletal support comprising a grid-like structure. The endoskeleton is further reinforced by a wider exoskeletal grid subdividing the matrix into separate discrete IEMs. The entire matrix is circumscribed by a thicker wider pillar, a matrix frame, to improve mechanical durability.

IEM Microporosity.

[1477] Given that that membrane structure is supported mechanically by the endoskeleton during operation, then ionomer charge hopping and IEM conductivity can be regulated by controlling microporosity of the membrane. Micropores comprise the natural crevasses present within a polymeric matrix where water and ions, either protons or hydroxyl ions may pass. In pure polymerization of a homogenous ion exchange membrane, only the unreacted monomers are loaded into a mold or casting unit whereby the film molecular density is determined by chemical bonding of specific length chains of the backbone and the sidechains. By contrast by introducing a sacrificial filler into the mold, the polymeric density is lowered by presence of the filler occupying intermediate locations within the matrix during polymerization.

[1478] Features of the intercalated sacrificial filler are exemplified in FIG. 104 by contrasting the same polymeric matrix including and absent the filler. Specifically in the left graphical schematic labelled (a), a simplified rendition of a pristine polymer is illustrated depicting a number of overlapping the carbon backbones 800c. The matrix may for example be formed by cross linking monomers loaded in a mold without any intercalating filler and subsequently polymerized under conditions of elevated temperature and/or pressure.

[1479] In this schematic representation, atomic bonds to other atomic species such as fluorine in polytetrafluoroethylene (PTFE) or polyfluorinated sulfonic acid (PFSA) or chlorine in polychlorotrifluoroethylene (PCTFE) are removed for the sake of clarity. Like panes in a stain glass window, the windows formed between the carbon backbones 800c function as pores in the membrane.

[1480] That said, this simplified rendering overstates the size of intra-matrix pores 801c. Instead in the center graphic (b) the carbon backbone 800e has been expanded to represent the real electrostatic surface of the carbon and its associated fluorine or chlorine adjuncts. The effective membrane pore size 801e in a charge constrained model of the matrix is significantly reduced. In order to increase the film porosity and pore size, an intercalating sacrificial filler like sucrose, glucose, fructose, or chitosan is included as a powder mixed with the carbon monomer prior to molding. During polymerization domains occupied by the filler leave large gaps 802 in the matrix where carbon bonding is absent. In this manner film porosity is increased improving membrane electrical conductivity.

[1481] In accordance with various embodiments of this invention, the filler must be removed by using a solvent or chemical solution that does not damage or disturb the polymer network. In general, solvent solutions comprising polar molecules dissolve solids comprised of polar molecules or salts. Conversely solvent solutions comprising non-polar molecules dissolve solids comprised of non-polar molecules. Since the polymeric backbone of the membrane comprises a non-polar molecular structure in order to include a sacrificial filler during polymerization and then subsequently remove it the filler should comprise polar molecules. By using polar sacrificial filler molecules within the non-polar membrane, the filler can be subsequently removed without damaging the polymer. For example, water can remove sugar as a filler without adversely affecting the polymeric membrane.

[1482] Alternatively, a sacrificial filler made in accordance with this invention may comprise an inorganic salt, an ester, or many other polar molecules in their solid form at room temperature. Polar molecular solids comprise geometries where one region has a net positive charge while the other portion has a negative charge, together forming an electrical dipole moment spanning an small intramolecular distance. When the electronegativity of two or more atoms in a molecule differ by more than 0.8, the more electronegative atom spatially redistributes the molecular electron cloud closer to its nucleus. This spatial redistribution creates a dipolar moment making the molecule appear charged even though the next charge state of the molecule is zero, i.e. it is not ionized. In extreme cases on imbalance the polar molecule is considered ionic. Examples of polar molecules useful as candidates for sacrificial fillers in ion exchange membranes include by example without limitation: [1483] Sugar, e.g. sucrose (C.sub.12H.sub.22O.sub.11), glucose (C.sub.6H.sub.12O.sub.6) or fructose (C.sub.6H.sub.12O.sub.6). [1484] Various inorganic salts such as sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl.sub.2), calcium chloride (CaCl.sub.2), and potassium iodide (KI). [1485] Molecular salts including ammonium chloride (NH.sub.4Cl), sodium carbonate (Na.sub.2CO.sub.3), potassium nitrate (KNO.sub.3), sodium sulfate (Na.sub.2SO.sub.4), copper(II) sulfate (CuSO.sub.4), and sodium bicarbonate (NaHCO.sub.3). [1486] Salts of organic acids including acetic acid (ethanoic acid) derived acetate salts such as sodium acetate (CH.sub.3COONa); citric acid derived citrate salts like sodium citrate (Na.sub.3C.sub.6H.sub.5O.sub.7) and potassium citrate (K.sub.3C.sub.6H.sub.5O.sub.7); lactic acid derived lactate salts such as sodium lactate (C.sub.3H.sub.5O.sub.3Na) and calcium lactate (C.sub.6H.sub.10CaO.sub.6); tartaric acid derived tartrate salts such as potassium sodium tartrate (KNaC.sub.4H.sub.4O.sub.6), aka Rochelle salt; malic acid derived malate salts, including sodium malate (C.sub.4H.sub.5NaO.sub.5) and magnesium malate (C.sub.4H.sub.4MgO.sub.5); oxalic acid derived oxalate salts like sodium oxalate (Na.sub.2C.sub.2O.sub.4) and calcium oxalate (CaC.sub.2O.sub.4); benzoic acid derived benzoate salts such as sodium benzoate (C.sub.7H.sub.5NaO.sub.2); succinic acid derived succinate salts including sodium succinate (C.sub.4H.sub.4Na.sub.2O.sub.4) and magnesium succinate (C.sub.4H.sub.4MgO.sub.4); fumaric acid derived fumarate salts like potassium fumarate (C.sub.4H.sub.2KO.sub.4); phthalic acid derived phthalate salts including diethyl phthalate (C.sub.12H.sub.14O.sub.4) and dibutyl phthalate (C.sub.16H.sub.22O.sub.4), ascorbic acid (vitamin C) derived ascorbate salts such as sodium ascorbate (C.sub.6H.sub.7NaO.sub.6) and calcium ascorbate (C.sub.12H.sub.14CaO.sub.12); and sorbic acid derived sorbate salts like potassium sorbate (C.sub.6H.sub.7KO.sub.2).

[1487] Aside from imbalances in atomic electronegatively, geometric shape plays an important role in determining if a molecule behaves as polar or non-polar in chemical reactions. In broad terms, pyramid-shaped and V-shaped molecules are generally considered to be polar whereas linear molecules are more non-polar in their behavior. The combination of electronegatively and geometry determine which solvents are best used to remove the sacrificial filler post-polymerization. While a list of every possible combination of filler and solvent is too expansive to include herein, it is generally known to those skilled in the art of chemistry which solvents dissolve various solutes.

[1488] Pragmatically, polar solvents are therefore best in dissolving polar molecules used as sold fillers during membrane formation. Mechanistically polar solvents exhibiting high dielectric constants can stabilize the positive and negative charges of solute molecules through dipole-dipole interactions and hydrogen bonding. Preferred polar-molecule solvents to dissolve polar fillers without damaging the membrane include the following: [1489] Deionized water (H.sub.2O). Often considered the universal solvent, water dissolves many polar substances due to its strong polarity and ability to form hydrogen bonds, but does not harm or degrade most polymers. [1490] Methanol (CH.sub.3OH). A polar solvent able to dissolve a wide range of polar compounds, methanol is soluble in water making it easy to rinse remaining solvent away after treatment. [1491] Ethanol (C.sub.2H.sub.5OH). Similar to methanol, ethanol is a common solvent able to dissolve many polar substances but with reduced toxic compared to methanol. Ethanol is soluble in water making it easy to rinse remaining solvent away after treatment. [1492] Acetic acid (CH.sub.3COOH). Due to the presence of a carbonyl group (CO) and a hydroxyl group (OH) within the molecule, acetic acid easily forms hydrogen bonds with other molecules, enabling it to dissolve a wide range of polar and non-polar compounds without damaging polymers [1493] Acetone (CH.sub.3COCH.sub.3, ace). A solvent with a medium polarity miscible with water, acetone is also good for dissolving many polar organic compounds. [1494] Ammonia (NH.sub.3). A polar solvent whose polarization arises from its trigonal pyramidal shape, with nitrogen (N) at the apex and three hydrogen (H) atoms at the corners of the base causing a region of partial negative charge near the nitrogen atom contrasting the more positive hydrogen atoms. Ammonia can dissolve many ionic compounds as well as other polar substances. [1495] Dimethyl sulfoxide (CH.sub.3).sub.2SO). Also known as DMSO, a solvent known for its ability to penetrate thin membranes including human skin. Care must taken in manufacturing to avoid inadvertent poisoning of machine operators by toxic substances transported by DMSO into the skin.

[1496] Other polar solvents include substances such as dimethylformamide or DMF (CH.sub.3).sub.2NC(O)H); N,N-dimethylacetamide or DMAc (CH.sub.3CON(CH.sub.3).sub.2); ethylene glycol (HOCH.sub.2CH.sub.2OH); propylene glycol (CH.sub.3CHOHCH.sub.2OH); tetrahydrofuran or THF (C.sub.4H.sub.8O), dioxane (C.sub.4H.sub.8O.sub.2); formamide (HCONH.sub.2); glycerol (C.sub.3H.sub.8O.sub.3); and pyridine (C.sub.5H.sub.5N). Another solvent, acetonitrile although versatile in dissolving a range of polar molecules is ill advised as is extremely dangerous causing severe health effects and/or death. Boric acid (H.sub.3BO.sub.3) dissolved in water may also act as a polar solvent even through it is not a polar solvent on its own. Alternatively bleach comprises a solution of sodium hypochlorite (NaOCl) in water. In a similar manner to boric acid, bleach itself is not a polar solvent on its own but inherits the ability to dissolve polar molecules from the polarized property of water. Care must be taken to completely wash all chlorine from a membrane before forming a catalyst layer as bleach is highly corrosive and oxidative substance and is therefore not recommended in CCM fabrication.

[1497] In another embodiment, temperature is used to eliminate the filler from a polymerized film. In such a case the filler may comprise a molecule with a melting point T.sub.m only slightly above the temperature of formation T.sub.f needed for monomer cross-linking but below the maximum allowable temperature T.sub.max to avoid damage to the polymeric matrix, or algebraically where T.sub.f<T.sub.m<T.sub.max. In this process, the solid filler is mixed with the membrane monomer, followed by polymerization at temperature T.sub.f. Thereafter the film is heated to the melting temperature of the filler Tm but below the maximum safe temperature T.sub.max of the polymeric matrix. During this step the filler melts into fluid and drains from the film. Alternatively the removal of the melted filler can be accelerated by using a heated solvent such as water or alcohol to help wash the dissolved filler from the membrane cavities.

[1498] Another method to use temperature as a control parameter for microporosity involves cold polymerization. In cold polymerization the temperature of the molding process is reduced with a corresponding increase in the mold pressure. The increased pressure enables polymerization of the ionomer at a lower temperature than at normal hot molding processes. By performing molding at a lower temperature the number of candidates for sacrificial fillers expands to include molecules with lower melting temperatures. Using cold polymerization, sacrificial fillers that might otherwise melt during hot molding can be employed. In such case a low melting temperature filler is mixed with the monomer and molded at high pressure with minimal heating. The polymerized film is then heater slightly at atmospheric pressure to melt the filler. During this step the filler melts into fluid and drains from the film. Alternatively the removal of the melted filler can be accelerated by using a warm but not hot solvent such as water or alcohol to help wash the dissolved filler from the membrane cavities.

[1499] As a completely different approach to controlling microporosity, the sacrificial filler may comprise an non-polar organic compound highly differentiated from the membrane polymer where the solvent used to remove the filler does not attack the membrane's polymeric matrix. Yet another approach employs using a powder comprising a low cost metal such as zinc or magnesium incorporated into the monomer powder. After polymerization the metallic sacrificial filler may be removed by a mild solution of hydrochloric acid.

[1500] Although the chemistry differs by the polymer used to form the membrane, the sacrificial filler used to form the micropores in the film, and the solvent used to remove the filler, the combination of chemicals used to form a microporous IEM in accordance with this invention requires the following criteria be met. [1501] The solvent used to remove the filler must not damage the polymeric backbone of the membrane [1502] The solvent used must not damage or degrade the electrically active charge group on the ionomer's pendant. [1503] The solvent should not leave corrosive residues in the membrane.

Polymer Bonding.

[1504] Another embodiment of this invention involves the use of molecular glue in fabricating the membrane. Molecular glue has two uses in the described processeseither to help adhere a hydrophilic ionomer to a hydrophobic backbone when fabricating a heterogenous composite reinforced membrane (CRM), to improve bonding between a homogenous hydrophilic ionomer and a hydrophobic endoskeleton, or to assist in cross linking of hybrid copolymers and block copolymers. In this manner the skeletal framework of a membrane may comprise entirely different plastics or composite materials than those used to form the thin ionomeric regions.

[1505] In the previous examples described herein, PVA treatment of PTFE was used to form a bridge between the hydrophobic PTFE and a hydrophilic ionomer such as PFSA. The same method can be applied to adhere a homogenous PFSA film to a PTFE pillar forming an endoskeleton. In this manner a molecular glue functions as if to cleave or clear certain areas of ionic charge causing localized hydrophobicity, replacing it with a bonding site for attaching sidechains, a process referred to as chemical grafting. In such an instance the sidechain functions as a buffer to physically separate the hydrophilic ionomer from the hydrophobic backbone. In reality, grafting PTFE to perform molecular gluing is a complex process and not simply an atomic substitution in the mainchain. This struggle to glue material onto a preformed film of PTFE is the consequence of its complete covalent bonds, a reason for it be criticized as an indestructible forever chemical dangerous to the environment.

[1506] In conclusion, very few solvents can degrade PTFE. According to the CP Lab Safety website it is because polytetrafluoroethylene (PTFE) is very non-reactive that renders it ideal for use with most chemicals. The only listed substances that degrade PTFE to any degree include chlorobenzene (mono); diethylamine; fluorine; gallic acid; gold monocyanide; lead sulfamate; mercuric cyanide; naphtha; as well as fuel oils, gasoline, and petroleum. Theoretically these agents could be used to treat PTFE to create graft points but care would be required not to degrade film stability.

[1507] An alternative mechanism to create graft points on a non-reactive hydrophobic backbone like PTFE can be achieved by treating the surface by a plasma or alternatively by sputter etching. Plasma etching is the process where a RF field is used to stimulate a gas to create a sea of chemically reactive ions which subsequently attack the target etch surface. Variables include the gas species used to create the plasma etchant ions, control of the chamber vacuum, pressure, and temperature, as well as the RF source power and oscillation frequency.

[1508] FIG. 105 graphically represents the process of grafting an conductive ionomer such as PFSA onto a hydrophobic inert fluorocarbon polymer. Starting with a pristine polymer shown in the left graphic labeled (a), PTFE comprises a mainchain backbone 810 with a string a carbon atoms 811 completely bonded to fluorine 812. This complete covalent bonding renders PTFE inert, stable, electrically insulating, and hydrophobic. To graft a pendant onto the mainchain, a reagent or plasma 814 strips away a fluorine atom modifying the molecular surface to expose a graft point 813 as shown in the center illustration labelled (b). In the final step labelled (c) on the right graphic a pendant comprising a sidechain 815 and ionomer 816 such as PFSA is bonded onto the graft point. The ability to graft a pendant onto the mainchain can be characterized by measuring the stability of the PTFE as quantified by required bonding force, surface tension, or surface energy of the film.

[1509] Bonding force, expressed as force in the cgs system as dynes is a measure of the attractive force a molecule, in this case the mainchain, exerts on ions to form chemical bonds, i.e. its ability to perform chemical bonding. The higher the molecular binding force the more chemically active material is. As a unit of measure one dyne equals 10.sup.5 kg m/s.sup.2 or a hundred thousandth of a newton, i.e. 10.sup.5 N, which also sometimes is expressed as a hundredth of a milli-newton or 0.01 mN. When a film has complete covalent bonding with no dangling bonds the surface energy is low meaning it is difficult to form bonds. Untreated, PTFE typically has a surface energy less than 28 dynes or 0.28 mN. A plasma treatment for only 5 minutes increases the surface energy of PTFE to 105 dynes, far above the minimum surface reactivity of 60 dynes generally required for adhesive bonding.

[1510] Another way to characterize the reactivity of a film is in terms of surface tension or surface energy, measured in milli-newtons per centimeter or dynes per centimeter where 1 dyne/cm=0.01 mN/cm. Although they have identical units surface energy is the equivalent attractive force present between the molecules at the surface of a solid substance while surface tension is the force required to produce a displacement of molecules at a specified distance. The poor wettability of PTFE refers to the ability to bond to PTFE after dry etching either by plasma etching PE or a related method referred to as reactive ion etching (RIE). As purported, dry etching profoundly impacts surface energy and surface tension as well as affecting available molecular contact anglesthe angle relative to the surface where molecular grafts may occur.

[1511] Specifically pristine PTFE exhibits a surface energy of 16 dyne/cm while plasma and RIE treated surfaces are improved by one-to-two orders-of magnitude to 0.76 dynes/cm and 0.2 dynes/cm respectively. The weaker surface bonding energy results in increased surface tension for the etched materials, enhancing wetting from 46 dyne/cm for pristine PTFE to 68 dyne/cm for PE treated films and to 74 dyne/cm for RIE processed PTFE.

[1512] Exemplary plasma process conditions ranged from RF power from 125 W-to-175 W, exposure times from 450 s-to-750 s and total gas flow rates from 60-to-100 sccm. The term sccm is an acronym for standard cubic centimeter per minute. The reactant gasses employed comprised oxygen and argon with oxygen comprising between 50% to 80% of the mix. Other papers have reported etching of superhydrophobic surfaces such as PTFE and various plastics using other reactant gasses such as CHF.sub.3 and SH.sub.6.

[1513] Alternatively sputter etching, using a non-chemically reactive method of momentum transfer may be used to activate the PTFE surface for bonding. Mechanistically, plasma etching strips fluorine from the polymer exposing carbon atoms in the backbone to facilitate grafting. Unlike wet chemistry etching involving sodium ammonia or sodium naphthalene, plasma etching does not generate wet stream or liquid waste.

[1514] So plasma etching aside, if wet chemical etching is not effective in removing fluorine from a PTFE coated surface how then how can PTFE-PVA-PFSA composite reinforced membranes (CRMs) be fabricated? This somewhat unexpected mechanism shown in FIG. 106 involves cross linking of PVA and PTFE nanoparticles to form a mechanical bond to the film surface by entanglement. Starting with a pristine backbone of PTFE 810 comprising carbon 811 and fluorine 812 is treated by spraying 819 or coating the membrane from a spray head 820 or other applicator with a nanoparticles suspension of PVA with PTFE nanoparticles 828. Some nanoparticles 817a are able to impregnate surface-pore area of the PTFE membrane as shown in the center graphic labelled (b).

[1515] After curing sown in the right most illustration labelled (c) the nanoparticles bond with themselves forming interstitial molecules 817b within the PTFE film covalently bonded via PVA 812 to a self organizing sidechain 823 connecting to an ionomer 815 such as PFSA. Once cured the interstitial nanoparticle molecule 817b provides mechanical locking of the entangled portion of the molecule within the PFSA structure without actually grafting itself onto the mainchain. This nanoparticle interlock facilitates mechanical and electrostatic attachment between the PVA-PTFE film below the PTFE surface and the PVA cross linkage to sidechains attached to its PFSA ionomeric terminus in the pendant. In this manner the ionomer adheres to the membrane mechanically and electrostatically without restricting the mainchain or necessarily forming new covalent bonds to the carbon backbone.

[1516] Process sequences may for example comprise starting with a PTFE membrane or skeleton spraying it with PVA, washing the film with ethanol, then stimulating cross linking to the polytetrafluoroethylene surface using glutaraldehyde. Alternatively PVA may be cross linked to poly(acrylic acid-co-2-acrylamido-2-methyl propane sulfonic acid), chemically as (P(AA-AMPS)), to enhance stability. Other composite membranes involve bonding using PVA with inorganic zirconium phosphate to form a highly stable composite membrane of PTFE-ZrP-PVA.

[1517] Still another category of nanoparticle surface modification involve polyoxyethylene (POE). In this process PVA and POE polymers are blended to form nanofibers using a process of electrospinning or electrospraying, fiber and film fabrication methods involving the simultaneous application of electric fields in the film or fiber formation process. In electrospraying employs a high voltage to disperse a liquid or for the fine aerosol through a small aperture liquid jet. Varicose waves on the surface of the jet lead form small and highly charged liquid droplets radially dispersed by Coulombic repulsive forces to form the fiber or film.

[1518] In a similar manner fiber production using electrospinning employ electric force to draw charged threads of polymer solutions or polymer melts into fiber several hundred nanometers in length. The fiber formation does not require chemical cross linking or high temperatures as the energy in imparted into bonding process electrostatically. In the example described, PTFE emulsion is blended with a carrier polymer solution such as polyethylene oxide (PEO) and poly(vinyl alcohol), i.e. PVA. Subsequent to electrospraying or electrospinning, sintering in nitrogen is performed, e.g. at 390 C. to fuse the PTFE into fibers or films while eliminating the carrier polymer. By controlling the blend, surface texture and surface energy of the film as formed can be adjusted from smooth to more porous membranes having rough surfaces supporting grafting and pendant attachment.

[1519] It should be mentioned that both polyoxyethylene (POE) and polyethylene oxide (PEO) refer to polymers of ethylene oxide. Somewhat confusingly however the terms are used in different contexts as distinguished by their molecular weight. In particular used in applications as thickening agents, the highly viscous polyethylene oxide (PEO) typically refers to the polymer with high molecular weight, while lower molecular weight polyoxyethylene (POE) is commonly used as a surfactant or emulsifier. Despite these differences, both PEO and POE consist of the same repeating unit, which is the ethylene oxide monomer (CH.sub.2CH.sub.2O).

[1520] In another fabrication method, a PTFE membrane is formed using polytetrafluoroethylene treated by a solution of chitosan (CS) crosslinked with poly(vinyl alcohol) using epichlorohydrin (ECH). Chitosan is a linear polysaccharide formed from shellfish and crustaceans composed of randomly distributed -linked D-glucosamine and N-acetyl-D-glucosamine. Chitosan is beneficial as a sacrificial filler in controlling film porosity in part because of its intrinsic fibrous structure. In film processing, the organochlorine compound epichlorohydrin, a toxic substance used in epoxy and miscible in polar organic solvents is employed to crosslink the PVA and chitosan followed by in situ chimeric SiO.sub.2 nanoparticle adhesion and water rinsing and/or soaking.

[1521] The modified PTFE membrane exhibits decreased carbon (C) and fluorine (F) content with a corresponding increase in hydrophilic groups. While developed for wastewater treatment, the enhanced hydrophilicity of the modified PTFE film makes the process a potential candidate for forming heterogenous composite reinforced membranes (CRMs) such as PTFE-PVA-PFSA as well as a means to glue homogenous PFSA ionomers onto a plastic or PTFE skeleton.

[1522] Made in accordance with this invention other embodiments comprise polymeric endoskeletal pillars strengthened by fibers such as carbon fibers, graphene, carbon nanotubes, polyamide and other long-chain aramid fibers, derived from an aromatic form of amides. Alternatively shards of harder polymer may be employed. In this context, aromatic refers to a conjugated ring of unsaturated bonds, empty orbitals exhibiting structural stability stronger than expected by the stabilization of conjugation alone.

[1523] Examples include hexagonal rings of six carbon atoms with an associated C-O groups connecting to N-H groups via amide linkages. By commercial taxonomy, at least 85% of the amide bonds must attach to two aromatic rings to be considered an aramid. Aramid physical properties include abrasion resilience, good resistance to organic solvents, electrically nonconductive, and featuring a very high melting point. Unencapsulated aramids are sensitive to acids, salts, electrostatic charge, and ultraviolet radiation.

[1524] Used as a strengthener, various forms of fibrous carbon or amides are generally embedded in thermoset like an epoxy resin, polydicyclopentadiene, polyimide, or other plastics. By mixing the different diameter particles-fibers into fiber layers in a 2D or 3D matrix, heterogeneity can improve the strength and resilience of endoskeletal support to thin membranes ush as ionomers. For example a PTFE-PVA-PVDF conjugate made in accordance with this invention for non energy uses can be repurposed to strengthen membrane endoskeletons despite representing a different application and field-of-art. As exemplified, creative elements of this invention is not the organic chemistry of forming the polymer backbone, but how to strengthen it, enable cross polymerization and bonding between dissimilar polymeric materials, control porosity, manage ionomeric functionalization to modulate conductivity while regulating hydration and swelling.

[1525] By introducing silicon hydroxyl groups onto the surface of polyacrylonitrile or PAN, a synthetic, semicrystalline organic polymer resin with the linear formula (CH.sub.2CHCN).sub.n, hydrophilic PAN-SiO.sub.2 fibers can be conjugated by molding or electrospinning with hydrophobic thermoplastic polyvinylidene difluoride PVDF formed by the polymerization of vinylidene difluoride to produce (C.sub.2H.sub.2F.sub.2).sub.n. The resulting PVDF-PAN-SiO.sub.2 fibrous plastic is stronger than numerous unstrengthened polymers.

[1526] In general the challenge to bond plastics of dissimilar polymers, especially category 1 plastics comprising polyethylene terephthalate (PET), category 2 comprising high-density polyethylene (HDPE), category 4 comprising low-density polyethylene (LDPE), and category 5 representing polypropylene (PP). Adhesives suitable for gluing polyethylene or polypropylene are generally labelled as such, but may fail if the surface morphology of the plastic is too dense or insufficiently porous to facilitate coating using nanofiber compounds.

[1527] Other more wettable plastics include category 3 for polyvinyl chloride (PVC) and category 9 for acrylonitrile butadiene styrene (ABS) which generally require either a solvent adhesive or epoxy compounds. Category 6 plastics comprising polystyrene (PS) is brittle and therefore not a suitable candidate for forming endoskeletal support for IEMs. Category 7 is the miscellaneous category including polycarbonate and acrylic requiring epoxy acrylic solvent adhesive, or cyanoacrylate. Other plastics may include acetal chemically known as polyoxymethylene or POM, a semi crystalline thermoplastic with high mechanical strength and rigidity.

[1528] In yet another embodiment of this invention, the PFSA ionomer can be attached to the rigid endoskeleton using a class of chemical bonding referred to as molecular glue. While traditional adhesives bond objects by physical adsorption effects which depend on a films surface energy, using a bis-diazirine reagent bonding is achieved through the formation of strong covalent bonds through promiscuous CH insertion, essentially clearing a region on a substrate surface the compound works by releasing N.sub.2 upon thermal or photo-chemical activation to afford reactive carbene species capable of undergoing efficient CH insertion with a wide range of polymer materials. Since the bis-diazirine reagent can react twice during bonding, it is able to form crosslinking delivering higher mechanical strength, improved flexibility without cracking, increased glass transition temperatures and more. Measured bonding strength between two pieces of high-density polyethylene (HDPE) exceed 2.3 MPa.

[1529] In summary, forming a heterogenous composite reinforced membranes (CRMs) such as PTFE-PVA-PFSA, grafting hydrophilic ionomers such as PFSA onto a PTFE mainchain, or bonding a homogenous film of PFSA to the polymeric skeletal structure made in accordance with this invention involve destruction of CF bonds to accommodate bonding or grafting hydrophilic pendants onto the matrix. Alternatively application of a layer of hydrophilic coating directly on the membrane surface using nanostructure locking may be employed. While the grafting process involves the application of expensive plasma etchers or hazardous chemicals, the surface coating method is simpler and lower in cost. Unfortunately in coated membranes, micropores may be blocked reducing water flux and film conductivity.

[1530] Highly soluble in water, non-toxic, biocompatible, hydrophilic, innocuous and non-carcinogenic, polyvinyl alcohol (PVA) with its abundant hydroxyl groups is therefore beneficial as a hydrophilic additive, but requires cross-linked by another material such as glutaraldehyde to remain stable in an aqueous phase. As an alternative surface modification of PTFE, chitosan (CS) a sugar-like molecule prepared by the deacetylation of chitin can be used in conjunction with PVA to affix a PVA-CS hydrophilic layer onto the fibril surface of the PTFE.

[1531] In a similar fashion, to form a stable aqueous solution chitosan must be cross linked to PVA using a reagent such as epichlorohydrin (ECH). Another option for bonding super hydrophobic skeletons to hydrophilic ionomers such as PFSA may involve compatible fluoropolymers, i.e. fluoropolymers that are chemically similar to PFSA such as FEP (fluorinated ethylene propylene) or PVDF (polyvinylidene fluoride) through sintering or electrospraying.

[1532] In general, chemically coating a super hydrophobic surface (SHS) with a hydrophilic layer requires a polar solvent such as PVA able to coat the SHS using electrostatic force without the need for disrupting CF bonds. In order to form a bridge to hydrophilic molecules such as PFSA, sucrose, or chitosan, to form a stable aqueous solution however, a reagent such as glutaraldehyde or epichlorohydrin is required to facilitate cross linking between a polar molecule such as an PFSA ionomer or a sacrificial filler and the carrier solvent such as PVA, polyethylene oxide (PE) or (P(AA-AMPS)). Membrane top view 3000 and membrane side view 3001 in FIG. 107 illustrate a variety of elements of composite ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising [1533] an ion exchange membrane 3003 composed of one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1534] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1535] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1536] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1537] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1538] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 formed by the introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1539] where an optional nanocoating 3020 is formed atop membrane 3003 to either enhance membrane conductivity or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1540] where ionomeric polymer 3002 may comprise a blend of PFSA 24 and PTFE 22 or other homopolymers, heteropolymers, copolymers, or blends of homopolymers, heteropolymers, copolymers as a mainchain expressing varying degrees of crystallinity and anisotropy; [1541] where ionomeric polymer 3002 may comprise varying lengths of fluorocarbon sidechains serving as pendants such as those found in Nafion, Aquivion, and Gore-Select influencing crystalline regularity, porosity, conductivity ands fuel crossover of the membrane; and finally [1542] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H 23, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkyl-ammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; [1543] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

PEM Ionomer Summary.

[1544] For positive ion charge transport known as cation exchange membranes (CEM) or proton exchange membranes (PEM) a suitable material rejects electron transport and inhibits negative ion transport but supports positive ion conduction across the membrane.

[1545] Key feature of a proton exchange membrane is a non-reactive non-conductive chemical backbone, typically a hydrophobic non-polar polymer such as PTFE attached to a network of pendants with an ionomer terminus, easily ionized to result in a net negative charge state, and thereby only capable of conducting positive ionic charge, i.e. cations. The membrane is sandwiched by thin catalyst layers comprising noble metals such as Pt or Pd and optionally metallic oxides interspersed within a carbon matrix.

[1546] On the anode the catalyst is used to strip electrons from hydrogen to form free conduction electrons and hydrogen ions, i.e. protons, in a chemical process referred to as oxidation. On the cathode side of the membrane, another layer of catalyst atoms helps promote electrical bonding among the incoming hydrogen ions, the circuitous electrons, and a reducing agent, typically oxygen. The byproduct of the reducing process is water.

[1547] The following table below considers a list of potential candidates for realizing a proton exchange membrane with good mechanical rigidity and durability, superior ion conductivity, and good specificity against anion transport and electron conduction. The table is arranged by classes of atomic structure used to form the membrane including homogenous PFSA or PFSA-hydrocarbon blends with or without sacrificial fillers; heterogenous compound reinforced membranes (hCRMs); inorganic-organic compound reinforced membranes (io-CRMs); polymer-inorganic hybrid matrix; acid-base blends; anhydrous proton conductors; bio-polymers; ionic polymers; block copolymers; radiation-grafted membranes; as well as proton conducting gels & hydrogels. While some of the listed or proposed PEM ionomers are applicable for fuel cells and electrolysis, other membranes are useful in filtration, electrodialysis, drug delivery, water purification, desalinization, and as coatings for surfaces and tubing. The following table lists the major categories of PEM membranes arranged in this application.

[1548] As shown, each section describes a category of ion exchange membrane comprising a variety of membrane structures and a list of enhancements including numerous embodiments made in accordance with this invention, comprising for example and without limitation chemically inert endoskeletal support with reinforcing fillers such as carbon fibers and polymer shards; chemical bonding of the ionomeric membrane to reinforced pillars of the endoskeleton via polar-nonpolar linkers and molecular glues; sacrificial fillers controlling film porosity; embedded nanoparticles; metallic organic frameworks (MOFs) containing catalysts, gas scavengers, and guest ionomers; and numerous combinations thereof. Note terms with a lowercase prefix s refer to sulfonated forms of the atoms, bit other acids such as phosphonic acid may be employed in lieu of sulphonic acid.

TABLE-US-00013 PEM Structure Category PEM Enhancements 1 PFSA bulk membranes PFSA endoskeleton, pillar link homopolymer sacrificial filler nanoparticle coating 2 PFSA-PTFE PFSA CRM endoskeleton, pillar link PFSA-PTFE-co-PTFE heteropolymer sacrificial filler PFSA-PVA-PTFE & composites nanoparticle coating 3 perfluorodimethyldioxole (PDD) amorphous endoskeleton, pillar link perfluoro-methylene-methyl-dioxolane- homopolymer sacrificial filler sulfonic acid (PFMMD-SA) glassy matrices nanoparticle coating 4 sulfonated polyethylene (sPE) polyethylene endoskeleton, pillar link bromated polyethylene (BrPE) (PE) polymers sacrificial filler 5 sulfonated polyvinyl alcohol (sPVA) polyvinyl alcohol endoskeleton, pillar link +cellulose acetate (PVA-g-CA) (PVA) polymers sacrificial filler +sulfosuccinic acid (PVA-SSA) & copolymers crosslinked copolymer +SSA grafted PVA (PVA-co-SSA) phosphorylated polyvinyl alcohol (PPVA) +phosphorus acid (PO.sub.3H.sub.2-PVA) +phosphoric acid (PO.sub.4H.sub.2-PVA) +phosphotungstic acid (PWA-PVA) +trimethoxysilylpropanethiol (TSMP PVA) +chitosan Na-alginate PVA 6 polyvinylidene fluoride (PVDF-SA) polyvinyl endoskeleton, pillar link +polyvinyl pyrrolidone (PVDF-PVP-SA) difluoride sacrificial filler +azobisiso butyronitrile (PVDF-AIBN-SPA) (PVDF) polymers crosslinked copolymers +perfluoro-hexene (PVDF-AIBN-SPA-PFH) & copolymers polyvinyl alcohol (PVDF-co-sPVA) polystyrene (PVDF-PVP-PSSA) polycarbonate (PVDF-co-sPC) methyl-methacrylate (PVDF-co-PMMA) perfluorosulfonic acid (PVDF-co-PFSA) 7 polypropylene CRM (PFSA-co-PP) polypropylene endoskeleton, pillar link polypropylene CRM (PFSA-PTFE-co-PP) (PP) copolymers sacrificial filler 8 sulfonated polyvinyl chloride (sPVC) polyvinyl endoskeleton, pillar link polyvinyl butylimidazolium grafted chloride (PVC) sacrificial filler polyvinyl chloride PVC-g-P(VBIm) polymers 9 sulfonated polyimide (sPI): ODADS polyimide (PI) endoskeleton, pillar link sulfonated polyimide (sPI): pBABTS polymers sacrificial filler 10 sulfonated polystyrene (sPS) polystyrene (PS) endoskeleton, pillar link styrenesulfonate (sSA) polymers & sacrificial filler cross-linked styrenesulfonate (sSA-X) copolymers 11 sulfonated poly fluorenyl ether fluorenyl ether endoskeleton, pillar link ketone nitrile (sPFEKN) ketone nitrile sacrificial filler polymers 12 polyphenylene disulfonic acid (PPDSA) polyphenylene endoskeleton, pillar link polybiphenylene disulfonic acid (PBPDSA) (PP) polymers & sacrificial filler linear/sidechain/kinked sulfonated copolymers crosslinked copolymer polyphenylene (sPP) branched copolymer +p-benzoyl/p-phenoxybenzoyl post-sulfonated phenylated (SDAPP) via Diels Alder condensate pre-sulfonated phenylated PPs polybiphenylene-co-phenylene disulfonic acid (BXPY) sulfonated polyphenylene - biphenyl (SPP-BP)/quaterphenol (SPP-QP) sulfonated polyphenylene - triphenol (SPPT), meta-biphenyl (SPPBm), ortho biphenyl (SPPBo), naphthyl (SPPN) sterically hindered pyridine moieties sulfo-phenylated polyphenylene (X + Y)N branched sulfo-phenylated polyphenylene (sPPB-x % DB) hydroxylated sulfonated phenylated polyphenylene (sPPP-OH) diiodo-biphenyldisulfonic acid (DiIPS) dibromo-biphenyldisulfonic acid (DiBrDS) sulfonimide branched poly (phenylenebenzophenone) (SI-PPBP) 13 sulfonated polyarylene ether (SPAE) polyarylene endoskeleton, pillar link sulfonated perfluoropolyether (sPFPE) ether (PAE) sacrificial filler sulfonated polyarylene ether sulphone polymers graphene oxide (GO) (SPAES) filler, graft, crystallites phosphotungstic acid crystallites (PWA) 14 sulfonated poly ether-ether ketone poly ether endoskeleton, pillar link (sPEEK or PEEK-sPEEK) ketones (PEK, sacrificial filler sulfonated poly ether ketone (sPEK) PEEK, PE.sub.xK.sub.y) sulfonated poly ether ketone-ketone (sPEKK) polymers sulfonated poly ether-ether-ether ketone (sPEEEK) sulfonated poly ether-ether ketone-ketone (sPEEKK) sulfonated poly ether ketone-ketone-ketone (sPEKKK) sulfonated poly ether ketone ether ketone- ketone (sPEKEKK) sulfonated (poly ether ketone) - poly ether ketone (sPEK-PEK or 2PEK) 15 sulfo poly ether-ether sulfone (sPEES, SPEESf) polymers and endoskeleton, pillar link sulfonated poly ether-ether sulfone-co- copolymers of sacrificial filler poly(ether imide) (sPEES-co-PEI, sPEESf- poly ether bismuth trimesic acid co-PEI) sulfones (BiTMA) sulfonated poly (phenylene ether-ether- poly ketone bismuth molybdate sulfone)-poly (acrylamido-methyl- ether sulfones (Bi.sub.2MoO.sub.6) propanesulfonic acid) (SP-PMPS) poly arylene fluorinated polyethersulfone (FPES, ketone ether FPESf, FPESU) sulfone di-poly(arylene ketone ether sulfone) (2PAKESf, 2PAKES, 2PAKESU) poly(arylene ketone ether ketone sulfone) (PAKEKS, PAKEKSf, PAKEKSU) sulfonated poly ether sulfone - bismuth trimesic acid heteropolymer (SPES- BiTMA, SPESU-BiTMA) sulfonated poly ether sulfone - bismuth molybdate heteropolymer (SPES- Bi.sub.2MoO.sub.6, SPESU-Bi.sub.2MoO.sub.6) sulfonated quaterphenol polysulfone (S.sub.4Ph-PSU, S.sub.4Ph-PSf) bis-hydroxyphenyl ether sulfone (BHPESf, BHPES, BHPESU) 16 membrane agnostic dopants, incl: hybrid polymer endoskeleton, pillar link PFSA-PTFE CRM with carbon sacrificial filler PFSA-PVA-PTFE CRM filler carbon nanotubes sulfonated polyarylene ether sulphone SO.sub.3H/COOH (SPAES, SPAESf) POH/NH.sub.2 sulfonated poly ether-ether ketone (sPEEK) SiO.sub.2/TiO.sub.2 sulfonated poly ether-ether sulfone graphene oxide (sPEES, sPEESf) PFPE-GO polyvinyl alcohol (sPVA) ABPBI-GO phenylene-bibenzimidazole (PBI) Hoffman GO chitosan (CS) Scholz-Boehn GO Ruess GO Lerf-Klinowski GO 17 membrane agnostic dopants, incl: hybrid polymer endoskeleton, pillar link PFSA-PTFE CRM with silica filler sacrificial filler PFSA-PVA-PTFE CRM HMS-PA phosphoric sulfonated polyarylene ether sulphone acid, hollow mesopore (SPAES, SPAESf) silica sulfonated polyether ether ketone (sPEEK) Al-graft mesopore silica sulfonated polyether ether sulfone silica-MCF (SPEES, SPEESf) mesostructured polyvinyl alcohol (sPVA) cellular foam phenylene-bibenzimidazole (PBI) chitosan (CS) 18 perfluoro-methyl-dioxolane-co-PFSA hybrid glassy endoskeleton, pillar link PFMMD-co-PFSA copolymer sacrificial filler PFMDD-co-PFSA (PFMMD-co-X) PFMD-co-PFSA PFMMD-co-PFMD-co-PFSA PFMDD-co-PFMD-co-PFSA +chlorotrifluoroethylene PFMMD-co-CTFE-co-PFSA PFMDD-co-CTFE-co-PFSA +pentafluorostyrene PFMMD-co-PFSt-co-PFSA PFMDD-co-PFSt-co-PFSA 19 poly(dioxo-dihydro-pyrrole-carbonyl) hybrid glassy endoskeleton, pillar link sulfanoyl fluoride-co-styrene (PDDP-CSFS) copolymer sacrificial filler PDDP-CSFS-co-SPmax (sulfo (phenyl (PDD-co-X) sulfonyl)-biphenyl high copolymer 20 sulfonated phenyl-alkane (sPhC.sub.nH.sub.2n+2) hybrid phenyl endoskeleton, pillar link phenyl-aldehyde (sPhCHO) copolymer sacrificial filler (phenyl-co-X) 21 styrene-co-X hybrid styrene endoskeleton, pillar link sulfo poly (trifluorostyrene) linear PTFS copolymers and sacrificial filler cross-link poly (trifluorostyrene) PTFS-X grafts cross linker perfluoroalkoxy alkanes polystyrene (styrene-co/g-X) sulfonic acid PFA-g-PSSA polystyrene co polystyrene-sulfonate copolymer PS-co-sPSS styrene-urethane poly thermoplastic urethane - polystyrene sulfonic acid - divinyl benzene PTPf-PSS-DVB flexible poly thermoplastic urethane ester - rigid poly thermoplastic urethane linear copolymer 22 sulfonated polysulfone P(Sf-sSf) hybrid polymer endoskeleton, pillar link (sulfone) sacrificial filler 23 polyamide sulfonimide P(Am-co-sAm) hybrid endoskeleton, pillar link copolymer sacrificial filler (polyamide) 24 poly sulfonated phosphazene P(Pz-co-sPz) hybrid polymer endoskeleton, pillar link (phosphazene) sacrificial filler 25 poly sulfonated siloxane P(SiX-co-sSiX) hybrid polymer endoskeleton, pillar link (siloxane) sacrificial filler 26 covalent triazine polymers CTP/sCTP hybrid polymer endoskeleton, pillar link sulfonated phenylated CTF-Ph (triazine) sacrificial filler tris(4-formylphenyl)amine sCTP-TPA Pd NP catalyst triazine trifluoride CTP-TF sulfonated triazine framework s6TPh sulfonated triazine framework s3T6Ph fluorinated triazine framework 6T6PhF.sub.4 sulfo bi-pyrroles triazine 6T12Ph6bPy sulfonated poly(arylene ether sulfone) triazine bisphenol linear copolymer P(SPAESf)-co-TBPh 27 sulfobutyl-vinylimidazolium-methyl hybrid methyl endoskeleton, pillar link methacrylate copolymer F.sub.3 methane methacrylate sacrificial filler sulfonate (sBVIm-TfO-co-MMA) copolymers PMMA nanoclusters polyester grafted poly(methyl P(MMA-co-X) Pd PMMA nanoclusters methacrylate) (PE-g-PMMA) Pd-MMA-MAA bridging maleic anhydride MAH - poly(methyl sulfonated PMMA methacrylate) linear copolymer nanoclusters P(MMA-co-MAH) PMMA porous maleic anhydride derivative Mi - poly nanospheres (methyl methacrylate) linear copolymer ZnS PMMA nanocluster P(MMA-co-MAH-co-Mi) polyvinylidene fluoride grafted poly(methyl methacrylate) (PMMA-g-PVDC) 28 carboxy methyl cellulose polyvinyl hybrid polymer endoskeleton, pillar link alcohol acrylamide (CMC-PVA-AA) (carboxy methyl sacrificial filler cellulose) carboxylated carbon nanotube (CCNT) sulfonated activated carbon (SAC) 29 multi-acid sidechains (MASC) modifying: hybrid polymer endoskeleton, pillar link PFSA-PTFE CRM (multi acid sacrificial filler PTFE with perfluoro imide acid (PFIA) sidechain MASC) PFSA-PVA-PTFE CRM sulfonated polyarylene ether sulphone (SPAESf, SPAES) sulfonated poly ether-ether ketone (sPEEK) sulfonated poly ether-ether sulfone (sPEESf, sPEES) polyvinyl alcohol (sPVA) phenylene-bibenzimidazole (PBI) chitosan (CS) 30 arylene ether IEM variants hybrid polymer endoskeleton, pillar link sP12F97B (arylene-ether) sacrificial filler sP6F9CB 31 POSS/DSSQ doped hybrid membranes POSS doped endoskeleton, pillar link PFSA-PTFE CRM hybrid polymers sacrificial filler PTFE with perfluoro imide acid (PFIA) polyhedral POSS variants PFSA-PVA-PTFE CRM oligomeric POSS-SH, POSS-A-PA, sulfonated polyarylene ether sulphone silsesquioxane POSS-PEG, POSS-iBu, (SPAESf, SPAES) (POSS) POSS-Vi, POSS-BuCl, sulfonated poly ether-ether ketone double decker Ot-POSS, OV-POSS, (sPEEK) silsesquioxane Ph-POSS, POSS-SH, sulfonated poly ether-ether sulfone (DDSQ) POSS-A, POSS-iBu-Vi, (sPEESf, sPEES) POSS-iBuNH.sub.2, polyvinyl alcohol (sPVA) POSS-iBuCl, phenylene-bibenzimidazole (PBI) POSS-iBu3OH, chitosan (CS) POSS-iBu-styrl POSS-iBu-PS, POSS-R-styrl, POS-R-PS, POSS-Cp-PS, POSS-Cy-PS, POSS-Am-NH.sub.2 POSS-cage & prisms: hexagonal & octagonal pendants, bead, chain, barbells, planar, dendritic, non-planar double decker silsesquioxane: cubic DDSQ, Me/non-Me DDQ 32 nanoparticle doped/coated hybrid IEMs hybrid polymer endoskeleton, pillar link extend polytetrafluoroethylene ePTFE nano fillers and sacrificial filler PFSA-PTFE CRM dopants of polyimide (PI) coating PTFE with perfluoro imide acid (PFIA) nanolayers nanocomposites PFSA-PVA-PTFE CRM nanofibers zirconium composite sulfonated polyarylene ether sulphone nanospheres electrospun nanofibers (SPAESf, SPAES) nanotubes nanoparticle coat CNTs sulfonated poly ether-ether ketone +polybenzimidazole PBI (sPEEK) +pyridine PyPBI sulfonated poly ether-ether sulfone NH.sub.2 CNT (sPEESf, sPEES) PtNH.sub.2 NP CNT polyvinyl alcohol (sPVA) TiNH.sub.2 NP CNT phenylene-bibenzimidazole (PBI) phosphorated titania chitosan (CS) PO.sub.4TiO.sub.2 CNT 4-sulfophthalic acid-poly vinyl alcohol sGA linker: sulfonated (SPA-PVA) glutaraldehyde novel nano-doped IEM polymers polyethylene oxide PEO poly(dopamine) (pDA) sulfonated polystyrene poly(sulfonated dopamine) (pSDA) nanofibers (sPS) poly(dopamine-sulfonated dopamine) Ag nanoparticles (p(DA-SDA) polytetrafluoroethylene - titanium (IV) butoxide sol-gel matrix 33 PFSA-PTFE CRM hybrid polymer endoskeleton, pillar link PFSA-PVA-PTFE CRM with fillers sacrificial filler sulfonated polyarylene ether sulphone (zirconium) intercalant zirconia iZr (SPAESf, SPAES) intercalant Zr sulfonated poly ether-ether ketone (sPEEK) +OH terminus ( type Zr) sulfonated poly ether-ether sulfone +O terminus ( type Zr) (sPEESf, sPEES) +X terminus ( type Zr) polyvinyl X = F.sup., Cl.sup., Br.sup., alcohol (sPVA) OH.sup., HSO.sub.4.sup. phenylene-bibenzimidazole (PBI) zirconium nanosphere chitosan (CS) ZrNS or ZrO.sub.2 4-sulfophthalic acid-poly vinyl alcohol (SPA-PVA) 34 grafted IEMs hybrid polymer endoskeleton, pillar link poly(vinylbenzyl chloride)-poly(4,4- with metal sacrificial filler diphenylether-5,5-bibenzimidazole)- organic metal oxide frame MOF triazole graft copolymer matrix frameworks +guest (PVBC-co-OPBI-co-OPBI-TG) (MOF) fillers +stack/cubic other MOF-doped IEMs +trapezoid PFSA-PTFE CRM +double trapezoid PTFE with perfluoro imide acid (PFIA) +hexagonal drum PFSA-PVA-PTFE CRM +octagonal drum sulfonated polyarylene ether sulphone +rectangular array (SPAESf, SPAES) metal complexes sulfonated poly ether-ether ketone (sPEEK) +Zr.sub.6O.sub.4(OH).sub.4 sulfonated poly ether-ether sulfone Cr terephthalate cluster (sPEESf, sPEES) sulfonic ferrous cluster polyvinyl alcohol (sPVA) M-L-M configurations sulfo phenylene- M-dithiolene, M-DPPE, bibenzimidazole (sPBI) M-EDT, M-PLTSC, sulfo chitosan (sCS) M-ambidentate, 4-sulfophthalic acid-poly vinyl alcohol M-BIPY, M-Schiff base (SPA-PVA) M-salicylaldehyde metal scavenger MOFs +metal scavenger via metal to hetero-metal ligand (M-L-hM) +ligand scavenger +guest scavenger +interleaved/stacked scavengers +scavenger guests Fe scavenger MOFs Co scavenger MOFs Ni scavenger MOFs zinc-oxide ester hexaphosphate MOF (Zn.sub.6O.sub.24(C.sub.6H.sub.18O.sub.24P.sub.6)) 35 PWA-doped polysulfone copolymer hybrid polymer endoskeleton, pillar link poly(4-vinylpyridine) (PSf-co-P4VP) with fillers and sacrificial filler +ferro-cyanide- coordinated poly(4- dopants molybdenum tungsten vinylpyridine) (CP4VP) ionomers (tungsten) nanoparticles (MoW NPs) PWA-doped poly vinyl alcohol with phosphotungstic acid quaternized polyethyleneimine silica clusters (SiO.sub.2-PWA) copolymer (PVA-co-QPEI) +chlorophenyl)methyl-dihydro benzodioxin-methyloxidanylidene- benzothiazine-carboxamide (R.sub.4N.sup.+) ionomers other PWA-doped IEMs PFSA-PTFE CRM PTFE with perfluoro imide acid (PFIA) PFSA-PVA-PTFE CRM sulfonated polyarylene ether sulphone (SPAESf, SPAES) sulfonated poly ether-ether ketone (sPEEK) sulfonated poly ether-ether sulfone (sPEESf, sPEES) polyvinyl alcohol (sPVA) sulfo phenylene-bibenzimidazole (sPBI) sulfo chitosan (sCS) 36 zeolite doped IEMs hybrid polymer endoskeleton, pillar link PFSA-PTFE CRM with fillers sacrificial filler PTFE with perfluoro imide acid (PFIA) (zeolite) phenylated zeolite PFSA-PVA-PTFE CRM sulfonated mordenite sulfonated polyarylene ether sulphone sulfonated zeolite (SPAESf, SPAES) frameworks sulfonated poly ether-ether ketone zeolite nanoparticles (sPEEK) sulfonated poly ether-ether sulfone (sPEESf, sPEES) polyvinyl alcohol (sPVA) sulfo phenylene-bibenzimidazole (sPBI) sulfo chitosan (sCS) 37 polysulfone IEMs acid-base endoskeleton, pillar link sulfonated polysulfone (sPSf, sPSU) polymers and sacrificial filler bromated polysulfone (BrPSf, BrPSU) fillers functionalized para-linked bromated polysulfone (polysulfone) graphene oxide (BrPSf).sub.x or (BrPSU).sub.x sulfonated polysulfone polysulfone filler doped IEMs (FPGO-sPSf, FPGO-sPSU) PFSA-PTFE CRM platinum titanium PTFE with perfluoro imide acid (PFIA) titanium dioxide PFSA-PVA-PTFE CRM nanoparticle sulfonated polyarylene ether sulphone (PtTiO.sub.2 NPs) (SPAESf, SPAES) polyoctahedral sulfonated poly ether-ether ketone silsesquioxanes (POSS) (sPEEK) sulfonated poly ether-ether sulfone (sPEESf, sPEES) polyvinyl alcohol (sPVA) sulfo phenylene-bibenzimidazole (sPBI) sulfo chitosan (sCS) 38 PBI/OPBI anhydrous IEMs anhydrous endoskeleton, pillar link poly phenylene-bibenzimidazole (p-PBI, polymers and sacrificial filler m-PBI) copolymers pristine electrospun poly oxydiphenylene-bibenzimidazole (PBI) PBI/OPBI nanofibers (OPBI) crushed electrospun +hexyl-vinylimidazolium dihydrogen PBI/OPBI nanofibers phosphate proton ion liquid hexachlorocyclo- (PHVIm-H.sub.2PO.sub.4) PIL triphosphazene (HCCP) poly dihydroxy phenylene (2OH-PBI) imidazolechlorocyclo- hexafluoroisopropylidene- triphosphazene (ImCCP) polybenzimidazole (F.sub.6-PBI) PBI-ZIF phenylene sulfur dioxide polybenzimidazole benzimidazole - zeolitic (SO.sub.2-PBI) imidazolate framework poly(arylene ether benzimidazole) (PAEBI) poly(2,5-benzimidazole) (ABPBI) cross linked PBI chains oxydiphenylene benzimidazole - poly(vinylbenzyl chloride) copolymer (OBPI-co-PVBC) +quaternary ammonia linked (DABCO, quinuclidine, quinuclidinol) +phosphoric acid (PA) doped oxydiphenylene benzimidazole - polyaniline copolymer (OPBI-PANI) +quaternary ammonia linked 39 chitosan (CS) biopolymer IEMs biopolymers & endoskeleton, pillar link chitosan poly(D-glucosamine) copolymers sacrificial filler chitosan poly(N-acetyl-D-glucosamine) chitosan P[HVIm] H.sub.2PO.sub.4 PIL sulfonated chitosan (sCS) cellulose functionalized CNT cross linked sulfonated chitosan (XL-sCS) alginic acid chitosan sulfonate (sCS) phosphorylated chitosan (pCS) functionalized CS bio-copolymer IEMs CS-co-polyacrylonitrile f(CS-co-PAN) CS-co-polystyrene f(CS-co-PS) CS-co-polyvinyl alcohol f(CS-co-PVA) CS-perfluorinated sulfonic acid (CS-PFSA) vinylpyridine CS graft (CS-g-PVP) +carbon nanotube (CS-g-PVP-CNT) styrenesulfonic acid CS graft (CS-g-SSA) +carbon nanotube (CS-g-PVP-SSA) POSS crosslinked chitosan (POSS XL CS)

1. PFSA Homopolymer IEMs.

[1549] As detailed previously homogeneous films of perfluorosulfonic acid having the acronym PFSA comprise the combination of a structural fluorocarbon backbone with sidechains bridging mainchain carbon atoms to sulfonic acid ionomers through intervening sidechains. Together the combination of the electrically active PFSA ionomer and its associated sidechain form a pendant, so named because it hangs off of the mainchain. As depicted previously in FIG. 2, the pendant frequency occurs at a semiregular repeating interval, which determines the conductivity of the film. The sidechain length and composition also vary in length depending on the monomer used in the fabrication process.

[1550] In homogeneous PFSA membranes the mechanical strength of the film is determined purely by its backbone while the sidechain length affects the film density and water transport. Without the sidechain the hydrophilic sulfonic acid would be unable to bond to the hydrophobic backbone. Pure PFSA films are however notoriously fragile and subject to swelling during operation. As one embodiment made in accordance with this invention, a homogenous membrane of PFSA is mechanically strengthened by am endoskeletal framework of stronger more-rigid polymers to which the PFSA attaches. The resulting structure reduces excess moisture retention and swelling of the film while improving handling. In another embodiment of the invention, the PFSA microporosity is controlled by inclusion of a sacrificial filler introduced during the dispersion casting and polymerization process.

[1551] Strictly defined, the backbone of pure PFSA can be categorized as the hydrophobic polymer polytetrafluoroethylene or PTFE which connects to the hydrophilic sulfonic acid ionomers through varying length sidechains, together able to function as a cation specific conduction medium. Pragmatically however, the term PTFE is generally used in reference to a non-conductive homopolymer, not to a blend of PFSA and PTFE. Instead PFSA-PTFE blends are heterogenous, and herein are referred to as a composite reinforced membrane or CRM.

[1552] The below table and similar tables to follow throughout the application describes the general structural category of the film, the mechanical structural support of the film, solvents and reagents used for mixing or delivering monomers and solutes, solvents and reagents used for promoting cross linking (denoted in the table by the abbreviation X-L), and various skeletal support options made in accordance with this invention.

[1553] The following table lists various attributes of a bulk PFSA homopolymer:

TABLE-US-00014 ionomer structure endoskeleton solvents, X-L fillers 1. perfluorinated PFSA polymer: PTFE, FEP, solv: PVA, PFOA, sac filler, CNTs, sulfonic acid homopolymer PE, PP. HFC, polyethylene oxides, POSS, bulk PFSA pillars: reinforced X-L: P(AA-AMPS) NPs, MOFs, PIL fillers (C-fiber/NT)

[1554] Nascent perfluorinated sulfonic acid, referred to as bulk PFSA is an ionomeric polymer comprising a hydrophobic mainchain with a perfluorinated sidechain pendant and a sulfonic acid ionomer as the sidechain terminus. Despite comprising a mainly tetrafluoroethylene (TFE) backbone blended with modified segment substituting the mainchain fluorine for an oxygen linked sidechain, pristine PFSA is considered a homopolymer. The copolymer of PFSA and PTFE, containing longer segments of poly tetrafluoroethylene (PTFE) mixed with PFSA sidechains is referred to as a hybrid composite reinforced membrane or CRM is discussed separately in section 2. The adjective bulk refers to the conduction mechanism, mainly that the conductive channels for ion transport in pure PFSA are bulk properties, not limited by surface conduction along the polymer's inner surfaces.

[1555] As previously articulated, one of the innovative features of the described cationic IEM or PEM is the integration of a chemically inert endoskeleton into the ionomeric membrane, providing both mechanical support and suppressing film swelling and contraction. Bonding between the PFSA and an inert endoskeleton depends on the compatibility of hydrophilic and hydrophobic components or upon bridging between the two. In fact, because of the inert nature of PTFE it remains challenging to bond it to anything. The best way to form PTFE bonded to PFSA is by co-molding them concurrently. Because the backbone of PFSA is tetrafluoroethylene, identical is composition but shorter in length than PTFE, the two spines are compatible and interchangeable.

[1556] Aside from polytetrafluoroethylene (PTFE), endoskeleton candidates able to bond to pure PFSA ionomeric films include fluorinated ethylene propylene (FEP), polyvinylidene fluoride (PVDF). Otherwise bonding to PTFE requires a cross linking adhesive such as PVA or a fluoropolymer-based glue. Endoskeletal candidates include polymers with low-energy surfaces such as polyethylene (PE) and polypropylene (PP).

[1557] Solvents used in the preparation of PFSA polymers involve poly vinyl alcohol (PVA); carcinogenic perfluorooctanoic (PFOA); hydrofluorocarbon (HFC) compounds comprising hydrogen, fluorine, and carbon; polyethylene (PE); and P(AA-AMPS), a copolymer of poly acrylic acid (AA) and 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS).

[1558] In various embodiments made in accordance with this invention, various fillers and dopants added to bulk PFSA films may include sacrificial fillers and permanent fillers. Sacrificial fillers may a comprise sugar on dissolvable solid whose solvent does not damage the polymer matrix during filler removal. Permanent fillers include (a) carbon fillers, (b) oxide fillers, (c) POSS fillers, (c) nanostructure fillers, (d) MOFs, and (e) solid acid fillers, ionic liquids, and PIL dopants. Among these, carbon fillers include functionalized nanotubes (CNTs), functionalized graphene oxide (GO), and functionalized carbon nanotubes (CNTs).

[1559] Oxide fillers include silica, zeolites, mordenite, nesosilicates, silica mesostructured cellular foam (Si-MCF), and hollow mesoporous silica (HMS). Metal oxides include molybdate, Al-grafted mesoporous silica (MCF-ionomer), zirconium-dopamine composites, intercalant zirconium. and phosphotungstic treated silica. Polyhedral and double decker oligomeric silsesquioxanes (POSS, DDSQ) include countless chemical and structural variants. Nanostructure fillers include metallic and ionic nanoparticles, nanospheres, nanoclusters, and nanofibers. MOFs include catalytic, ionomeric, and scavenger metals in various geometries. Solid acids, ionic liquids and PILs comprise additives used to control conductivity through film pH.

2. PFSA-PTFE Heteropolymer & CRM IEMs.

[1560] As described, a heterogenous |EM polymeric film comprising a blend of a PFSA monomer with a mechanical support polymer such as PTFE, PFMMD, PDD, styrenesulfonate, polyethylene, polystyrene, ketone nitrile, polyphenylene, poly-arylene, polyamide, poly-ketone (PEEK), and other carbon or hydrocarbon compounds. Such heterogenous films are referred to as a composite reinforced membranes or CRM in recognition that the backbone, generally hydrophobic, provides mechanical support. Compared to pure bulk conducting perfluorinated sulfonic-acid (PFSA), however, many composite reinforced membranes (CRMs) achieve stability only by sacrificing ionomeric density resulting in lower current densities and reduced conductivities.

[1561] In accordance with the Grotthuss mechanism of hopping conduction between protons and water molecules, high proton conductivities result mainly from protons, i.e. ionized hydrogen, released from sulfonic acid groups able to hop along the ionomers aided by local vehicular water molecules. Only by either increasing microporosity to enhance water membrane permeability or by increasing the densities of ionomeric pendants can proton transport be improved. Accordingly the greater the microporosity or the higher the density of sulfonic acid groups in the membrane, the higher the density of hydronium ions transporting ionic charge, and the greater the net proton conductivity. Because, however sulfonic acid is hydrophilic and TFE is not, forming a secure bond to a hydrophobic backbone like PTFE subsequent to PFSA polymerization requires a solvent or glue such as PVA for intermolecular bonding. As such, a heteropolymer IEM comprising a PVA-bonded coating of PFSA atop a hydrophobic TFE-PTFE mainchain is referred to in the above table as a PFSA-PVA-PTFE composite reinforced membrane. It should be understood that in a porous membrane filled with nooks and crannies like Swiss cheese, the term surface has two different meanings which in some discussion may be ambiguous.

[1562] In its macrostructural context, the surface of the membrane is the two dimensional atomic plane forming an interface with the catalyst layer comprising the CCM, i.e. the catalyst coated membrane. In a microstructural context, the inner walls of any chamber, pore, conduit, tube, or channel present within the polymer matrix represents a microscopic surface along which surface current can flow. So while the macrostructural surface of the IEM is perpendicular to the fuel cell's current flow, conduction within the membrane is parallel to the microporous surfaces and orthogonal to the macrostructural surface.

[1563] For this reason, hybrid PFSA-PTFE CRM membranes may be considered as surface conductors rather than bulk conductors because the hydrophobicity of PTFE limits internal hydration suppressing bulk vehicular transport of hydronium ions within the pores instead relegating cation conduction to charge hopping from ionomer-to-ionomer occurring along the exposed inner surfaces of the pores. To enhance the conductance of a CRM, the density of micropores must be increased to maximize the films internal surface area thereby exposing more sulfonic acid ionomeric groups to contribute in charge transport, analogous to enhancing the surface area of activated charcoal in a filter. Alternatively, additional protons can be added using membrane doping by ionic liquids.

[1564] By contrast, significantly increasing the size rather than the density of pores within an ionomer suffers from numerous drawbacks. Although larger pores enhance film hydration enhancing vehicular transport of hydronium ions, the larger pores increase the preponderance of fuel crossover and oxygen back streaming. When pores become too large the incoming hydrogen fuel source entering the anode comprising either hydrogen gas in a H.sub.2 fuel cell or methanol in a direct methanol fuel cell (DMFC) is able to transit unimpeded from the anode into the cathode without first being ionized into protons. Significant fuel crossover in large pore membranes is problematic for a variety of reasons. This means porosity is a key factor is determining IEM performance and limiting fuel crossover.

[1565] Firstly, un-ionized hydrogen crossover wastes fuel. Hydrogen gas passing unimpeded from anode to cathode is released into the atmosphere unused as a gaseous effluent without enhancing fuel cell electrical conduction or generating electricity. Secondly, if the hydrogen gas content in the oxygen rich cathode exceeds a certain concentration, a flammable gaseous mix of H.sub.2 and O.sub.2 may result in the cathode. Thirdly, hydrogen reacting with oxygen in the cathode can produce hydrogen peroxide (H.sub.2O.sub.2) that diffuses into the ionomeric membrane. The hydrogen peroxide bonds to the sulfonic acid groups inhibiting their proton exchange ability and permanently degrading the ionomer and fuel cell operation. In this scenario ionomer damage is likely non-uniform with the greatest impairment of ionomer function located nearer the cathode. As such, transport through the damage zone relies exclusively on vehicular transport with greatly diminished charge hopping conduction. The net result is lower fuel cell current, higher voltage sag, lower film conductance, reduced energy efficiency, and greater heat dissipation.

[1566] The formation of overly large pores in the membrane can also encourage oxygen back streaming. the process whereby unreacted oxygen gas flows from the cathode across the membrane into the anode. Once there, the oxygen invariably reacts with the hydrogen rich atmosphere producing hydrogen peroxide (H.sub.2O.sub.2). The anodically generated H.sub.2O.sub.2 then diffuses into ion exchange membrane bonding to sulfonic acid ionomer groups degrading the fuel cell performance in a manner similar to the effect of cathodic hydrogen peroxide except that the damage zone, the region of greatest functional impairment, is closest to the anode rather than the cathode.

[1567] Another adverse effect of a membrane with excessive large pores is diminished mechanical strength. Like osteoporosis in living bone, an overly porous membrane becomes brittle and easily damaged from stresses incurred during manufacturing and handling. Moreover, large pores easily retain excess water causing the membrane to swell excessively during operation in humid ambient conditions, especially at high current densities. Conversely, during inactivity membrane stored water easily drains from large pores causing drying and film contraction. Humidity cycling during operation repeatedly causing swelling and drying stresses the film eventually precipitating microcracks in the membrane which grow in length and size until the membrane leaks gas and can no longer operate reliably or safely.

[1568] To avoid these various failure modes, a heterogenous ion exchange membrane made in accordance with this invention includes some combination of (i) micropores and nanopores fabricated with consistent dimensions and densities, (ii) strengthened endoskeletal support to limit film stresses from handling and humidity cycling, and (iii) a nanocoating to prevent carbon monoxide and other gaseous toxins from invading the cathode and damaging the catalyst coated membrane (CCM) core of the fuel cell. These preventative measures may include molecular blockers, metal scavengers, and antidotes to unwanted chemical toxins. These protective measures may be incorporated into the ionomeric membrane matrix, into the catalyst layers, and optionally into the gas diffusion layer. Protection against environmental contaminants need only be into the cathode side of an MEA5 as the cathode air exchange is exposed to the unfiltered ambient while the anode gasses are self-contained and thereby protected from contamination.

[1569] Membrane top view 3000 and membrane side view 3001 in FIG. 107 illustrate a variety of elements of ionomeric polymer 3002 comprising a composite reinforced membrane (CRM) of PFSA-PTFE made in accordance with this invention, including separately or in combination inventive matter comprising: [1570] an ion exchange membrane 3003 composed of one or more polymeric chains 3009c including ionomers 3009i present along the backbone or connected to the mainchain via a pendant sidechain; and/or [1571] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1572] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1573] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1574] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1575] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole or pore in place of the sac-filler; and/or [1576] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1577] where ionomeric polymer 3002 may comprise perfluorinated sulfonic acid (PFSA) 24 linearly bound to fluoropolymer polytetrafluoroethylene (PTFE) 21 to form a heterogenous composite reinforced membrane of PFSA-PTFE; copolymerized with polyvinyl alcohol (PVA) to form a heteropolymer of PFSA-PVA-PTFE able to bond to other materials including endoskeletal pillars; or where the PFSA-PTFE composite is blended with other homopolymers, heteropolymers, or copolymers forming the mainchain and controlling crystallinity and fuel crossover in the matrix. Alternatively the PFSA 24 chain may comprise a separate chain cross linked to a separate PTFE chain 21 (not shown). [1578] where ionomeric polymer 3002 may include sidechains or pendants 22 whose length and composition control crystalline regularity, and influencing porosity, conductivity, and fuel crossover of the membrane; [1579] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H 23, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1580] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1581] In an alternative embodiment of the invention the structural membrane is coated with a colloidal dispersion of solvent and PFSA, i.e. where nanoscopic particles of PFSA are suspended in the solvent forming small primary aggregates of three-to-four molecules as dictated by the polar solvent chemistry. During curing, these clusters then agglomerate into secondary aggregates on the order of hundreds of nanometers in size forming rodlike structures 1 nm in diameter depending on the ratio of water to alcohol in the solvent. The dispersion also naturally forms chemical bonds to the semi-rigid endoskeleton made in accordance with this invention as described previously for FIG. 106, especially when treated with PVA. The resulting membrane is identified in the forgoing table as PFSA-PTFE dispersed nanoparticles.

[1582] In another embodiment made in accordance with this invention, membrane conductivity is improved by increasing porosity using a process involving the introduction and subsequent removal of a sacrificial filler as part of the membrane fabrication sequence resulting in vacancies in the polymeric matrix appearing as empty bubbles referred to herein as sacrificial pores 3005. Like the endoskeletal support frame, the sacrificial filler process is equally applicable to heterogenous CRM membranes formed using either a PFSA-PVA-PTFE process and structure, a dispersion of PFSA-PTFE nanoparticles, or a combination thereof.

[1583] As copolymers of PFSA and PTFE, these hybrid films including PFSA-PTFE and PFSA-PVA-PTFE ionomeric polymers comprise composite reinforced membrane or CRMs providing mechanical resilience and durability advantages over PFSA. Because however, PTFE is a dense semi-crystalline electrically insulating and hydrophobic polymer, its incorporation into a PFSA polymer invariably reduces membrane conductivity by suppressing vehicular transport of hydronium through bulk channels. Instead electrical conduction is limited to proton transport via charge hopping along the PFSA backbones, comprising the so-called Grotthuss mechanism. Since the conduction throughout the matrix occurs through ionomer termini of sulfonic acids arranged linearly along PFSA chains, the cross sectional area of charge transport channels is reduced by the presence of excess PTFE either as separate chains or as PFSA with extended portions of PTFE 21 in the mainchain, i.e. where m>>n. Mechanistically, the impact of the preponderance of PTFE groups in the matrix is charge transport behavior similar to surface conduction, consequentially resulting in a more resistive film.

[1584] To compensate for a decreased conductance, the hybrid film must be thinned to 20 m or less relying on the mechanical strength of PTFE to prevent film breakage during handling. Made in accordance with this invention, the introduction of a reinforcing endoskeleton into the membrane provides added mechanical support for handling of the film, thereby allowing the mole fraction of PTFE in the blend to be reduced. By reducing the fraction of PTFE in the polymer, conductance is enhanced by a higher density of PFSA chains and through greater porosity. The number of conductive pores is further enhanced by the introduction of a sacrificial filler such as sucrose into the polymer prior to casting and subsequently removing it to form micropores.

[1585] The micropores are able to transport protons, water and hydronium ions. Hydrogen atoms, oxygen atoms, hydronium ions, and water molecules have effective diameters of 0.08 nm, 0.13 nm, 0.2 nm, and 0.28 nm respectively, meaning all four masses should be able to pass through any pore 0.3 nm in diameter. In a hydrogen fuel cell oxygen back-streaming from the anode to the cathode to the anode is minimal, not because of pore size but because of a small yet perpetual positive pressure differential between the anode and cathode maintained by the hydrogen gas supply. accordingly hydrogen gas flow occurs primarily from anode to cathode attached to larger water molecules, forcing oxygen to swim upstream against a prevailing current. As such, a reasonable density of micropores can be introduced into the PEM membrane to enhance conductivity without significantly increasing oxygen back-streaming, i.e. crossover.

[1586] In the case of a DMFC, the maximum pore size is limited by the need to prevent fuel crossover, the unwanted flow of methanol across the membrane. Methanol is a relatively large molecule having an average diameter of 0.36 nm, nearly double that of an hydronium ion. Because of its larger molecular dimension, channels in the membrane with dimensions greater than 0.2 nm but less than 0.35 nm will transport protons but prevent methanol cross-over.

[1587] As such, the introduction of sacrificial fillers into the mold casting process forms conductive channels in the polymeric matrix facilitating the ability to adjust conductance of a membrane independent of its thickness. One such sacrificial filler made in accordance with this invention is sucrose or alternatively fructose or glucose. Sugars comprise rather large molecules compared to elemental atoms, but are diminutive contrasted to hydrocarbon fuels and large polypeptides such as proteins. Specifically, sucrose has an average cross sectional dimension of 0.7 nm to 0.9 nm. In the sacrificial filler process described herein, dissolved sucrose leaves empty regions called vacancies or sac pores in the polymer matrix. These vacancies appearing as holes or bubbles in the polymer roughly equal to the molecular dimensions of the sacrificial filler used to create them.

[1588] While these vacuous bubbles may appear overly large compared to oxygen and methanol, in reality sacrificial sucrose does not form contiguous pores of the same size as its vacancy bubbles. Instead, at low sucrose concentrations the bubbles do not overlap but connect through smaller channels in the polymer matrix, analogous to the small openings in a spider web. These narrow conduits serve as choke points limiting gas flow. Being a semi-amorphous semi-crystalline polymer, it is impossible to predict a-priori the actual size and density of gas channels created in a PFSA-PTFE CRM by a sacrificial filler process. Instead, an optimum degree of porosity can be determined empirically by adjusting the quantity of filler mixed with the polymer for casting and measuring the tradeoff between conductivity and undesirable back-streaming or adverse fuel crossover effects. Alternatively, if film porosity is too great, a smaller sacrificial sugar such as fructose or glucose may be used in place of sucrose.

[1589] Aside from the important role of sacrificial fillers in PEM fabrication as described in various embodiments made in accordance with this invention, permanent fillers and dopants added to the matrix can further enhance mechanical and electrical film properties. A permanent filler is a foreign material not a monomer of the chain which once introduced and molded into the polymer remains indefinitely as part of the polymeric matrix. Permanent fillers include (a) carbon fillers, (b) oxide fillers, (c) POSS fillers, (c) nanostructure fillers, (d) MOFs, and (e) solid acid fillers & PIL dopants.

[1590] Among these, carbon fillers include functionalized nanotubes (CNTs), functionalized graphene oxide (GO), and functionalized carbon nanotubes (CNTs). Oxide fillers include silica, zeolites, mordenite, nesosilicates, silica mesostructured cellular foam (Si-MCF), and hollow mesoporous silica (HMS). Metal oxides include molybdate, Al-grafted mesoporous silica (MCF-ionomers), zirconium-dopamine composites, intercalant zirconium. and phosphotungstic treated silica. Polyhedral and double decker oligomeric silsesquioxanes (POSS, DDSQ) include countless chemical and structural variants. Nanostructure fillers include metallic and ionic nanoparticles, nanospheres, nanoclusters, and nanofibers and may include ionic or metallic functional groups. MOFs include catalytic, ionomeric, and scavenger metals in various geometries, where homogeneous and heterogenous elemental metal atoms and metallic clusters are suspended in a matrix or organic ligands. Solid acids and PILs comprise additives used to control conductivity through film pH. The discussion of fillers and dopants, while mentioned here specifically in the context of a PFSA-PTFE film, the concept is general and applies equally for all membrane types.

[1591] The composition of PFSA-PTFE composite reinforced membranes including its ionomer type, heteropolymeric backbone structure, solvents used in its synthesis, composition of its inventive endoskeleton, and novel use of fillers and dopants is listed in the table below. Structurally, the attachment of a PFSA-PTFE film to a support endoskeleton is neither trivial nor obvious, particularly if the pillars forming the endoskeleton are also made of a hydrophobic PTFE matrix.

TABLE-US-00015 ionomer structure endoskeleton solvents, X-L fillers 2. perfluorinated sulfonic PFSA CRM polymers: PTFE, solv: PVA, PFOA, sac filler, CNTs, acid poly tetrafluoro heteropolymers FEP, PE, PP HFC, ethanol, PE oxides, POSS, ethylene pillars; reinforced X-L: P(AA-AMPS), NPs, MOFs, PIL PFSA-PTFE fillers (C-fiber/NT) TFE, GA PFSA-PVA-PTFE

[1592] Solutions to this bonding problem include (a) co-molding the membrane and the pillars at the same time where separate mold chambers containing different mold materials cross link during polymerization possibly aided by a cross-linking agent like glutaraldehyde (GA) or tetrafluoroethylene (TFE), (b) damage the endoskeletal pillars with a chemical etch or radiation to create bonding sites for the membrane to attach to, (c) form bondable groups on the pillars so that the membrane can attach itself, (d) coat the pillars with an adhesive that can glue to the membrane, or (e) form a copolymer membrane where one of the polymer groups readily attaches to the pillar. This process and the resulting connection between the endoskeletal pillar and the membrane is referred to herein as a pillar link. Although the pillar link is most challenging when hydrophobic polymers such as PTFE are involved, the methods described are applicable to any combination of endoskeletal and ionomeric membrane material and will not be repeated again for each section.

3. Amorphous Glassy Matrix Homopolymer IEMs.

[1593] In an alternative embodiment, the inert molecular backbone of a composite reinforced membrane is modified using an alternative homopolymer chemistry having a lower atomic density than PTFE. An example of this approach is illustrated in FIG. 108 where the PTFE hydrophobic mainchain is chemically modified into a more porous compound PFMMD 1020a or PDD 1020b without disturbing pendant sidechain 1022 or sulfonic ionomer 1023. Such molecules form amorphous structures exhibiting lower-densities than the more crystalline-like PTFE polymer. Various methods may be used to form an amorphous glassy matrix ion exchange membrane.

[1594] In an exemplary PFMMD 1020a structure as depicted. one of the CF.sub.2 bonds in the m-repeat group of PFSA is replaced by a fluorinated carbon-oxygen ring 1024 to form a perfluoro-(2-methylene-4-methyl-1,3-dioxolane) membrane having the acronym PFMMD. The structural change impacts both bulk and interfacial membrane permeabilities affecting oxygen solubility, diffusivity, interfacial permeation rate constants, and ionomer distribution in the catalyst layer. While the increased permeability may weaken CRM strength, when used in conjunction with the semi-rigid endoskeletal frame made in accordance with this invention, film porosity as determined by the m-to-n ratio of the polymeric repeated units for PFMMD can be optimized without concern for affecting membrane mechanical properties such as strength, durability, and swelling.

[1595] In an alternative implementation PDD 1020b one of the CF.sub.2 bonds in the m-repeat group of PFSA is replaced by a cross-linked oxygenated fluorocarbon attached to trifluoromethyl groups to form a ring-structured monomer 1023, perfluoro-(2,2-dimethyl-1,3-dioxole) also know as PDD. By enhancing membrane permeability, oxygen transport resistance is reduced enhancing PEM conductivity. Another benefit of the enhanced permeability is an increase in interfacial catalytic activity and suppression of layered backbone folding of the ionomer near the catalyst surface.

[1596] Fabrication of glassy amorphous films involves a two-step processpolymerization and hydrolysis. FIG. 109 describes the process flow for forming amorphous glassy matrix membranes from starting materials PDD.sub.m and PSVE, followed by polymerization, and subsequent hydrolysis. The exemplary process flow describes forming PDD starting with the PDD monomer precursor 1025 comprising perfluoro(2,2-dimethyl-1,3-dioxole) mixed with PSVE perfluoro(3-oxapent-4-ene) sulfonyl fluoride containing pendant 1022p and a fluorinated sulfonic group 1023f comprising SO.sub.2F.

[1597] Like PFSA-PTFE, polymerization of glassy matrices ensues by slowly stirring the components in an inert atmosphere with a polymerization initiator [CF.sub.3(CF.sub.2).sub.2 C(O)O].sub.2 for example available from Tokyo Chemical Industry Co., Ltd dissolved in Vertrel XF solvent available from DuPont-Mitsui Fluorochemicals Co., Ltd for three days. Vertrel XF is a proprietary hydrofluorocarbon (HFC) fluid designed to replace current hydrochlorofluorocarbon (HCFC) and perfluorocarbon (PFC) fluids and well suited for use in vapor degreasing equipment for cleaning, rinsing, and drying.

[1598] The polymer is then heated to 100 C. to remove fluid. Hydrolysis is performed by immersing the film in NaOH aqueous solution and heating to 130 C. for 12 hours, followed by rinsing in HCl and deionized water at 80 C., thereby converting fluorinated side group 1023f into a hydrolyzed terminus 1023h to realize sulfonic ionomer 1023. Through hydrolysis, the polymer perfluoro-(2,2-dimethyl-1,3-dioxole) (fPDD) 1020f is thereby converted into hydrolyzed perfluoro-(2,2-dimethyl-1,3-dioxole) (hPDD) 1020h.

[1599] Although these membranes hold promise in fuel cell, electrolysis, and filter applications they are inherently glassy and brittle requiring added mechanical support especially during manufacturing and MEA7 assembly. As such, membrane integrity can be greatly enhanced through integration with the endoskeletal and exoskeletal support and frame.

[1600] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 110 illustrate a variety of elements of amorphous glassy ionomeric polymers 3002 made in accordance with this invention, including separately or in combination inventive matter comprising [1601] an ion exchange membrane 3003 composed of one or more polymeric chains 3009c including ionomers 3009i present along the backbone or connected to the mainchain via a pendant sidechain; and/or [1602] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1603] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1604] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1605] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1606] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in its place of the sac-filler; and/or [1607] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1608] where ionomeric polymer 3002 may comprise a sulfonated amorphous material or glassy matrix such as hydrolyzed perfluoro-(2,2-dimethyl-1,3-dioxole) aka PDD 1020h comprising a fluorocarbon or other homopolymers, heteropolymers, copolymers, or blends forming the mainchain and controlling crystallinity and fuel crossover in the matrix; [1609] where ionomeric polymer 3002 may include sidechains or pendants such as trifluoromethyl radical in perfluoro-(2,2-dimethyl-1,3-dioxole) aka PDD.sub.m 1025.sub.m or poly(perfluoro-2-methylene-4-methyl-1,3-dioxolane) aka PFMMD disrupting crystalline regularity, and influencing porosity, conductivity, and fuel crossover of the membrane; where a PFMMD can form a copolymer with PFSA; [1610] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR.sub.4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1611] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1612] A summary of fabrication conditions for glassy IEMs is described in the table below.

TABLE-US-00016 ionomer structure endoskeleton solvents, X-L fillers 3. glassy amorphous amorphous polymer: PFMMD, solv: DMF, HFB, sac filler, CNTs, matrix glassy CRMs & PMMA, PU, PVDF. DEC oxides, POSS, PDD homopolymers pillars: reinforcing X-L: FBzO, FDTBO, NPs, MOFs, PIL PFMMD fillers (C-fiber, CNTs) PFDMO

[1613] As described, a glassy amorphous IEM comprises a composite reinforced membrane comprising PDD, PFMMD, or any other homopolymer having large groups that interfere with polymer crystallinity. Although any number of endoskeletal materials may be used in pillar construction, molecules of similar composition to the membrane such as PFMMD, PMMA, PU, and PVDF offer better bonding strength then hydrophobic perfluorinated materials. Exemplary solvents include dimethylformamide (DMF), hexafluorobenzene (HFB, F.sub.6Bz), and diethyl carbonate (DEC). During synthesis, cross linking agents include perfluorodibenzoyl peroxide (FBzO).sub.2 or simply FBzO, perfluoro-di-tert-butyl peroxide (FDTBO), and perfluoro-dimethyl-dioxolane (PFDMO). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

[1614] Applications of glassy amorphous membranes include gas separation membranes and proton exchange membranes for hydrogen fuel cells.

4. Functionalized Polyethylene (PE) Polymer IEMs.

[1615] As an alternative to a composite reinforced membrane comprising a fluorocarbon backbone such as PTFE, enhanced mechanical stability can also be achieved using a fluorine-free membrane comprised of hydrocarbon homopolymers known as a polyolefins. One example of a polyolefin is polyethylene (PE), functionalized into a catalyst or ionomer by sulphonic acid or other electronically active groups. By definition, polyolefins are polymerized versions of basic olefins, i.e. unsaturated hydrocarbons containing a double bond between two carbon atoms.

[1616] Olefins, or using a more modern term alkenes, as depicted schematically in FIG. 111 comprise styrene monomers 1028 subsequently linked through polymerization to form a supporting backbone 1029. Unlike PTFE, this backbone comprises only hydrocarbons with no fluorine and therefore circumvents ongoing health and environmental concerns regarding fluorocarbon PFAS forever chemicals. Polyolefins represent a distinct class of polymers separate from thermoplastics and other polymer chemistries having the general form (CH.sub.2CHR).sub.n where R is an alkyl group.

[1617] Specifically styrene comprises a modified benzene ring 1027 with the chemical formula C.sub.6H.sub.5CHCH.sub.2 where one of the hydrogen bonds has been substituted by a vinyl group 1026 having a chemical structure CHCH.sub.2. During polymerization, the vinyl double bond 1026 is split forming two single bonds with adjacent styrene monomers 1025. Post polymerization, the resulting backbone 1030 of the polyolefin binds the modified benzene rings 1027 together in a string. Structurally analogous to the fluorocarbon backbone in PTFE and PFSA, the polyolefin spine comprises only hydrocarbons. Commercial examples of polyolefin plastics include polyethylene (PE), polypropylene (PP), polyisobutylene, and polymethylpentene (PMP). Shorthand notation often represents polyolefin spine only as the backbone 1030 absent the attached ring structures.

[1618] One structural form of a polyolefin suitable for forming an ion exchange membrane (IEM) is the class of polymers referred to as polyethylene aka PE. FIG. 112 depicts an exemplary process flow for fabricating a polyolefin polymer membrane of polyethylene by grafting a bromated hydrocarbon onto a polyethylene backbone. An exemplary process involves two steps, first by grafting sulfuryl chloride onto the polyethylene's backbone 1030, then using reagent 1031 acting on sulfuryl chloride 1032 to perform a substitution with pendant sidechain 1033 with trimethyl amine pendant 1034n.

[1619] Finally the trimethyl amine pendant 1034n terminus is modified by into an active bromated ionomer 1035i by bromomethane CH.sub.3Br. Alternatively sulfuric acid H.sub.2SO.sub.4 can be used to form a SO.sub.3H sulfonic acid ionomer. Numerous pragmatic issues challenging the functionalization of PE include managing film porosity, enhancing conductance, and controlling durability as required by real world applications of fuel cells and electrolyzers.

[1620] In particular, high density polyethylene (HDPE) sheet is susceptible to environmental stress cracking (ESC), a brittle failure that occurs when the HDPE sheet cracks while in tension. Unsupported, HDPE can fail at tensile stresses lower than normal levels. By combining it with the skeletal support described herein, the tensile strength of a PE membrane can be enhanced significantly.

[1621] By adopting the inventive features of the application, the performance of polyethylene (PE) membranes can be greatly enhanced. Improvements include (a) sacrificial fillers to control film porosity and conductivity, (b) endoskeletal support to improve film strength and durability and to reduce swelling, (c) nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) occurs, and (d) doping with fillers and PILs to enhance bulk conductivity in the film.

[1622] As previously mentioned, although PE membranes hold promise in fuel cell, electrolysis, and filter applications they can become brittle over time, especially when exposed to light and various chemical agents. They also suffer from high thermal expansion, stress cracking, and poor temperature performance. Some of these deficiencies can be overcome by providing added mechanical support especially during manufacturing, MEA7 assembly, and during operation. As such, membrane integrity can be greatly enhanced through integration with the endoskeletal and exoskeletal support and frame. Given its poor thermal performance, it is important to avoid excessive temperatures.

[1623] The method of limiting self heating by dividing a fuel cell into micro-stacks is especially valuable in realizing a reliable PE based IEM and fuel cell. In summary, membrane top view 3000 and membrane side view 3001 in FIG. 113 illustrate a variety of elements of a polyolefin ionomeric polymer 3002, in this case comprising polyethylene (PE).

[1624] Made in accordance with this invention, inventive features include: [1625] an ion exchange membrane 3003 composed of one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1626] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1627] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1628] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1629] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1630] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; [1631] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1632] where ionomeric polymer 3002 may comprise the polyolefin polyethylene (PE) as mainchain 1030 optionally blended or cross linked to other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1633] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel cross-over of the membrane; [1634] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR.sub.4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1635] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1636] A summary of fabrication conditions for polyethylene IEMs is described in the table below including descriptions of the ionomer, endoskeleton, solvents, and fillers.

TABLE-US-00017 ionomer structure endoskeleton solvents, X-L fillers 4. functionalized homopolymer polymers: PE, EVA, solv: TCE, xylene, sac filler, CNTs, polyethylene PE membrane EPDM, PU, PP. toluene, TCB oxides, POSS, sPE pillars: reinforcing X-L: azo, H.sub.2O.sub.2, NPs, MOFs, PIL BrPE fillers (C-fiber, CNTs) silane

[1637] Made in accordance with this invention, a homopolymer membrane comprising a polyethylene (PE) backbone with a trimethyl amine pendant functionalized by an active bromated or sulfonated ionomer terminus is described for fabricating sPE and BrPE IEMs with endoskeletal support. Endoskeletons as disclosed may comprise a range of materials but offer superior bonding to a PE membrane for ethylene-vinyl acetate (EVA) copolymers because EVA contain PE compatible ethylene units; ethylene propylene diene monomers (EPDMs) pursuant to suitable surface treatments increase PE surface bonding energies; polyurethane (PU) as a commonly used post surface treatment PE adhesive; polypropylene (PP) through welding, i.e. localized concurrent melting of PP and PE polymers.

[1638] Suitable PE solvents include aromatic hydrocarbons such as trichloroethane (TCE), xylene, toluene, and trichlorobenzene (TCB). PE cross linking agents generate CC and CH links. Compounds include azo, i.e. chemicals with a diazinyl (HNNH) functional group; peroxide (H.sub.2O.sub.2), and silane (SiH.sub.4). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

[1639] In contrast to other polymers, the impermeability of polyethylene to water means its application in hydronium vehicular transport, thereby relegating all conduction mechanisms within the film to either charge hopping along ionomers grafted onto the PE mainchain, or by interaction with ionomeric fillers or ionic liquids. As such, ionomeric conduction in polyethylene films is similar to that of PFSA-PTFE in that charge transport exhibits a surface like behavior rather than bulk conduction.

5. Functionalized Polyvinyl Alcohol (PVA) Polymer IEMs.

[1640] Another fluorine-free category of ion exchange membranes is based on homopolymers, heteropolymers, and copolymers of polyvinyl alcohol (PVA). FIG. 114 describes an exemplary process flow for synthesis of a heterogenous polymer membrane based on combining phosphorylated polyvinyl alcohol (PVA), phosphorylated (PA) cellulose acetate (CA), and glutaraldehyde (GA) to form the polymeric ionomer PVA-PA-CA. As shown, one exemplary process involves a polymerization reaction of phosphorylated polyvinyl alcohol (phos-PVA, pPVA) 1060 with phosphorylated cellulose acetate (phos-CA) 1061 using the crosslinking agent glutaraldehyde (GA) 1062 to yield polyvinyl alcohol-grafted-cellulose acetate 1063 comprising a PVA polymeric backbone 1060p attached via GA pendant 1062p to hydrogen phosphate [HPO.sub.4].sup.2 1061p also referred to monohydrogen phosphate [PO.sub.3(OH)].sup.2. The terminus hydrogen phosphate in turn bonds to an active ionomer such as cellulose acetate or sulfonic acid.

[1641] By phosphorylating PVA and combining it with cellulose acetate PVA can be adapted for use in methanol fuel cell applications. Alternatively, insulating PVA can be functionalized into a conductive ionomer by grafting sulfonic domains at the hydroxyl side group of the polymer backbone or by doping the film with sulfonated graphene oxide.

[1642] Membrane top view 3000 and membrane side view 3001 in FIG. 115 illustrate a variety of elements of polyvinyl alcohol ionomeric polymer 3002 comprising a grafted polyvinyl alcohol (PVA) made in accordance with this invention, including separately or in combination inventive matter comprising: [1643] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1644] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1645] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1646] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1647] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1648] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1649] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1650] where ionomeric polymer 3002 may comprise poly vinyl alcohol (PVA) 1061p as a mainchain grafted to an ionomer 1061p comprising cellulose acetate (CA) or sulfonated graphene oxide; [1651] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1652] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; or alternatively by combining phosphoric acid with cellulose acetate (CA) grafted onto the PVA backbone; and finally [1653] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1654] Aside from grafting, poly vinyl alcohol can also be functionalized by attaching an aromatic organic compound such as a phenyl as a pendant bound to an ionomer such as sulfonic acid SO.sub.3H. FIG. 116 illustrates a process flow for synthesis of sulfonated polyvinyl polymer where sulfosuccinic acid (SSA) 1066 is used to treat polyvinyl alcohol (PVA) 1065 forming the polymeric ionomer PVA-SSA 1067. For example, two PVA chains may be cross linked by sharing a sulfonated 1,4 di-carbonyl ring for use in pervaporative separation of liquids but made in accordance with this invention PVA membranes can be adapted for ionomeric applications by integrating (a) sacrificial fillers to control film porosity and conductivity, (b) endoskeletal support to improve film strength and durability and to reduce swelling, (c) a nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) limits throughput, and (d) doping with fillers and PILs to enhance bulk conductivity in the film.

[1655] In addition to its use in PEM based hydrogen fuel cells, poly vinyl alcohol films can also be adapted for used in direct methanol fuel cells (DMFCs). Methods include doping with H.sub.3PO.sub.2 or H.sub.3PO.sub.4; doping with phosphotungstic acid (PWA) aided by the reagent dimethylsulfoxide (DMSO); blending with chitosan and sodium alginate; and synthesizing PVA-layered silica nanocomposite membranes. Another method involves forming a heterogenous PVA-silica sulfonated membrane employing a trimethoxysilylpropanethiol (TMSP) sol-gel process in the presence of PVA solution.

[1656] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 117 illustrate a variety of elements of polymer 3002 comprising PVA made in accordance with this invention, including: [1657] an ion exchange membrane 3003 composed of one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1658] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1659] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1660] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1661] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1662] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1663] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1664] where ionomeric polymer 3002 may comprise the poly vinyl alcohol (PVA) 1067 as a mainchain, optionally blended or cross linked though crosslinking ionomer 1009x to other PVA chains or to dissimilar homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1665] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane where the pendants and/or ionomers may also serve to perform crosslinking among chains; [1666] where ionomeric polymer 3002 may comprise an ionomer 3009i or crosslinking ionomer 3009x of reactive sulfonic acid groups SO.sub.3H, sulfosuccinic acid groups C.sub.4H.sub.6O.sub.7S, carboxylic acid groups COOH, phosphoric acid groups PO.sub.3H.sub.2, phosphorous acid PO.sub.4H.sub.2, phosphotungstic acid (PWA), imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, trimethoxysilylpropanethiol (TMSP), or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1667] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1668] The below table summarizes various structures, ionomers, endoskeletons, solvents, cross-linkers, and fillers used to synthesize PVA membranes made in accordance with this invention comprising a heterogenous membrane of polyvinyl acid (PVA) homopolymers and heteropolymers with a variety of sidechains, grafts, and copolymers.

TABLE-US-00018 ionomer structure endoskeleton solvents, X-L fillers 5A. sulfonated polyvinyl heterogenous polymer: PVA, PAA, solv: methanol sac filler, alcohol PVA polymers PEG, PVP, starch ethanol, DMSO, CNTs, NPs, sPVA & copolymers pillars; reinforcing DMF, maleic acid, oxides, PIL PVA-g-CA fillers (C-fiber, CNTs) glyoxal, STMP, CA POSS, MOFs, PVA-SSA X-L: GA, SHMP, DA, PVA-co-SSA SA, SSA 5B. phosphorylated polyvinyl alcohol PPVA (PO.sub.3H.sub.2, PO.sub.4H.sub.2) PWA-PVA TSMP PVA chitosan Na-alginate PVA

[1669] Membrane functionalization includes ionomers of sulfosuccinic acid C.sub.4H.sub.6O.sub.7S; sulfonic acid SO.sub.3H; cellulous acetate (CA); phosphorous acid (H.sub.2PO.sub.4,), phosphoric acid PO.sub.3H.sub.2, phosphotungstic acid (PWA, PTA), and trimethoxysilylpropanethiol groups aka TMSP. Endoskeletons compatible with PVA membranes include polyacrylic acid (PAA) and polyvinylpyrrolidone (PVP), able to form hydrogen bonds with PVA; polyethylene glycol (PEG) able to form copolymers with PVA; starch, able to form biodegradable polymers with PVA, and cellulose such as carboxymethylcellulose (CMC) able to form composites. Suitable PVA solvents include water, dimethyl sulfoxide (DMSO), ethanol, methanol, and dimethylformamide (DMF).

[1670] Cross linking agents include glutaraldehyde (GA), glyoxal, maleic acid, citric acid, trisodium trimetaphosphate (STMP), sodium hexametaphosphate (SHMP), dianhydride (DA), succinic acid (SA), and sulfosuccinic acid (SSA). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

6. Functionalized Polyvinyl Difluoride (PVDF) Polymer IEMs.

[1671] Another class of fluorocarbon free ion exchange membranes is based on functionalized homopolymers, heteropolymers, and copolymers of the hydrocarbon polyvinyl difluoride (PVDF). FIG. 118 describes a process flow for synthesis of a PVDF membranes based on combining polyvinylidene fluoride (PVDF) 1070, polyvinyl pyrrolidone (PVP) 1071, and polystyrene sulfonic acid (PSSA) 1073 to form the polymeric ionomer PVDF-PVP-PSSA 1075. The resulting compound comprises three copolymeric chainspolyvinyl pyrrolidone (PVP) 1071, polyvinylidene fluoride (PVDF) 1070, and polystyrene sulfonic acid (PSSA) 1073. Unusually polyvinyl pyrrolidone PVP 1071 not only serves as a polymeric chain but also participates in copolymer cross linking.

[1672] In this matrix, the ionomer SO.sub.3H 1074 not only participates in ion exchange but also through hydrogen bonding provides added crosslinking among the chains. One example of PVDF polymerization is used to achieve high actuation response for a polymer metal composites actuator Although the used is in the fabrication of actuators and sensing, in accordance with this application such PVDF synthesis can be adapted and repurposed for ionomer applications such as fuel cells, electrolysis, and filtration by integrating the inventive features of (a) sacrificial fillers to control film porosity and conductivity, (b) endoskeletal support to improve film strength and durability and to reduce swelling, (c) nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) occurs, and (d) doping with fillers and PILs to enhance bulk conductivity in the film.

[1673] FIG. 119 illustrates exemplary polymers able to bond with polyvinylidene fluoride (PVDF) 1070 in forming ionomeric copolymers. Options include polyvinyl alcohol (PVA) 1065 which can be sulfonated via an extra oxygen bond to produce the copolymer sPVA-PVDF also written as sPVA-co-PVDF; poly(methyl methacrylate) (PMMA) 1068 to produce the copolymer PMMA-PVDF-SA also as PMMA-co-PVDF-SA; sulfonated polycarbonate (sPC) 1069 to produce the copolymer sPC-PVDF also written as sPC-PVDF, and perfluorosulfonic acid (PFSA) 24 yielding PFSA-PVDF also referred to as PFSA-co-PVDF.

[1674] In particular the monomer PFSA 24 includes hydrogen bond 22 to sulfonic acid group 23 and inert hydrophobic PTFE chain 21a, or combinations thereof. Various synthesis methods include PVDF/PMMA composite membranes for seawater desalination by gap membrane distillation antifouling for waste water treatment. Although PVDF polymers are used in desalinization and water filtration and the general literature does not discuss or imply their use in fuel cells and electrolysis, the function of PVDF copolymer membranes can be adapted for ionomeric applications by integrating the inventive features of (a) sacrificial fillers to control film porosity and conductivity, (b) endoskeletal support to improve film strength and durability and to reduce swelling, (c) nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) occurs, and (d) doping with fillers and PILs to enhance bulk conductivity in the film.

[1675] FIG. 120 illustrates process flow for synthesis of a polymer membrane based on combining polyvinylidene fluoride (PVDF) 1070, polyvinyl pyrrolidone (PVP) 1071, and sulfamic acid (SA) 1078s to form the tri-blended 1079 polymeric ionomer PVDF-PVP-SA comprising two polymeric chains PVDF 1070 and functionalized PVP chain 1071p with attached ionomer 1078.

[1676] FIG. 121 illustrates a process flow for synthesis of a polymer membrane by converting polyvinylidene fluoride (PVDF) 1070 into dehydrofluorinated polyvinylidene fluoride (D-PVDF) 1070d by stripping hydrogen and fluorine from a segment of the mainchain identified by its repeat length n.sub.2. Portions of the polymer left unmodified are identified by the segment of length n1, whereby the starting length n is split in two so that (n1+n2)=n. The D-PVDF 1070d is next combined with 3-sulfopropyl acrylate (SPA) 1080 and azobisisobutyronitrile (AIBN) 1081 to form tri-blended PVDF copolymer PVDF-AIBN-SPA 1082. The linear copolymer comprises three mainchain constituent componentsa PVDF portion 1083a, a dehydrofluorinated segment 1083b, and a hydrocarbon segment 1083c with an attached ionomer 1085 via pendant 884.

[1677] FIG. 122 illustrates a process flow for synthesis of a polymer membrane by combining dehydrofluorinated polyvinylidene fluoride (D-PVDF) 1070d with 1H,1H,2H-perfluoro-1-hexene (PFH) 1082, 3-sulfopropyl acrylate (SPA) 1080, and azobisisobutyronitrile (AIBN) 1081 to form quad-blended PVDF-based copolymer PVDF-AIBN-SPA-PFH 1084 comprising four linear copolymer segments identified as PVDF 1083, dehydrofluorinated PVDF 1083b along with hydrocarbon chains 1083c and 1083d each containing sidechains While hydrocarbon segment 1083d is attached to fluorocarbon copolymer sidechain 1086, hydrocarbon segment 1083c is bonded to pendant 1084 with ionomeric terminus 1085.

[1678] FIG. 123 illustrates a process flow for synthesis of a PVDF-based copolymer membrane by combining polyvinylidene fluoride (PVDF) 1070 and hexafluoropropylene (HFP) 1087 with diisopropyl peroxidicarbonate (DIPPDC) and 1,1,2-trichlorotrifluoroethane (R-113) to produce bi-blended PVDF polymer PVDF-HFP 1088 subsequently sulfonated by treatment in CI-SO.sub.3H and HCl to produce the resulting bi-blended sulfonated PVDF copolymer sPVDF-HFP 1089. A variety of means to synthesize poly(vinylidene fluoride-co-hexafluoropropylene) exist in the scientific literature.

[1679] Although published papers discuss various PVDF applications including actuators, filter, and fuel cells, none address the fundamental problematic issues of PVDF membranes, namely excessive swelling, low mechanical strength, poor film durability, and low cathodic reaction rates. By integrating the inventive features of this application, the ionomeric performance of PVDF copolymers can be greatly enhanced. These elements include (a) sacrificial fillers to control film porosity and conductivity, (b) endoskeletal support to improve film strength and durability and to reduce swelling, (c) nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) occurs, and (d) doping with fillers and PILs to enhance bulk conductivity in the film.

[1680] Membrane top view 3000 and membrane side view 3001 in FIG. 124 illustrate a variety of elements of an ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising: [1681] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1682] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1683] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1684] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1685] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1686] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1687] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1688] where ionomeric polymer 3002 may comprise polyvinylidene difluoride (PVDF) as a mainchain optionally blended or cross-linked to other homopolymers, heteropolymers, copolymers for secondary structure including without limitation PVP-PSSA, PMMA, PC, PFSA, PFSA-PTFE, PVP-SA, AIBN-SPA, AIBN-SPA-PFH, or HFP, thereby controlling varying degrees of film crystallinity and anisotropy; [1689] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1690] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1691] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1692] Made in accordance with this invention, an ion exchange membrane comprising homopolymers, heteropolymers, and copolymers of a polyvinyl difluoride (PVDF) backbone with a variety of sidechains, grafts, and copolymers is disclosed. Examples include PVDF copolymerized with combinations of PVP, AIBN, SPA, HFP, PFH, PC and PFSA.

[1693] By controlling the mix of constituent moieties, the blend provides an added degree of structural support whereby the polymer's structure can be considered a heterogenous composite reinforced membrane or CRM. These various PVDF copolymers may be functionalized by sulfonating the copolymer backbones of polystyrene (PS), polyvinyl alcohol (PVA), polycarbonate (PC), perfluorosulfonic acid (PFSA), polyvinyl pyrrolidone (PVP), or by sulfonating dehydrofluorinated portions of a PVDF mainchain.

TABLE-US-00019 ionomer structure endoskeleton solvents, X-L fillers 6. sulfonated heterogenous polymers: PVDF, solv: DMF, NMP, sac filler, CNTs, polyvinylidene-fluoride PVDF CRM PMMA, PTFE, EVA, MEK, ace, TEP, oxides, POSS, PVDF-SA PE, PAm, PMP, ABS, ethanol, esters, NPs, MOFs, PIL PVDF-PVP-SA TPU, PEEK THF, chloroform. PVDF-AIBN-SPA pillars: reinforcing X-L: TAIC, MEP, PVDF-AIBN-SPA-PFH fillers (C-fiber, CNTs) PVP diamines, PVDF-co-sPVA BPO. PVDF-PVP-PSSA PVDF-co-sPC PVDF-co-PMMA PVDF-co-PFSA

[1694] Endoskeletal support compatible to bond with a PVDF membrane include poly(methyl methacrylate) (PMMA), polytetrafluoroethylene (PTFE), ethylene-vinyl acetate (EVA), polyethylene (PE), polymethylpentene (PMP), polyamides (PAm, nylon), acrylonitrile butadiene styrene (ABS), thermoplastic polyurethane (TPU), polyether ether ketone (PEEK), and polyethylene-co-vinyl acetate (EVA). Other endoskeletal materials can be chosen to bond to the corresponding copolymers in the film.

[1695] Solvents potentially involved in forming PVDF include dimethylformamide (DMF), N-methyl-2-pyrrolidone (NMP), methyl ethyl ketone (MEK), acetone (ace), ethanol, tetrahydrofuran (THF), chloroform, triethylphosphate (TEP), and various esters. Cross linking agents involved in PVDF synthesis include triallyl isocyanurate (TAIC), and a macromonomer of ethylene oxidepropylene oxide (MEP), diamines such as hexamethylenediamine, benzoyl peroxide (BPO), and polyvinyl pyrrolidone (PVP). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

7. Polypropylene (PP) CRM Copolymer IEMs.

[1696] The hydrocarbon polypropylene (PP) has the potential for use in composite reinforced ion exchange membranes, not as an ionomer but as a copolymer or composite to strengthen mechanical weaker polymers. Electrically, its low surface energy and non-polar hydrophobic nature makes it a poor candidate as a ionomeric conductor. Moreover, its low surface energy also renders it a poor candidate for grafting ionomeric pendants except by using radiation damage. Instead pristine PP is relegated to providing mechanical support in composite reinforced membranes constructed from other polymers better suited for supporting conduction.

[1697] Accordingly, FIG. 125 illustrates the composition of a PP membrane 1090 comprising a blend of intertwined polypropylene (PP) 1091 and perfluorosulfonic acid (PFSA) 1092. Benefits of a blended membrane offer the mechanical strength PP and the conductivity. In processing of a PP-PFSA blend, monomers of polypropylene and of PFSA and PFSA-PTFE are mixed and loaded into a casting mold as described previously in this application. The mixing may comprise solid powder versions of the two monomers or by mixing both components in water, then drying the well blended mix back into powder form.

[1698] The monomers used to create PFSA polymers which typically include a vinyl ether with a sulfonyl fluoride precursor group can post polymerization, be hydrolyzed to form the sulfonic acid group. For example, in the case of Nafion production, the sulfonyl fluoride groups in the monomer can be hydrolyzed to sulfonic acid groups after polymerization. This step is usually done intentionally in a controlled manner to convert the precursor polymer to the functional PFSA polymer with its characteristic ion-exchange properties. The polymerization process itself must however be carefully controlled to ensure that the resulting polymer has the desired molecular weight and properties. Impurities, including water, can affect the polymerization process, but water does not chemically damage the PFSA monomers.

[1699] A less attractive alternative involves pre-mixing in solution by dissolving both monomers in a polar-nonpolar solvent mix for example comprising xylene or decalin to dissolve PP monomers and using highly fluorinated solvents, such as perfluorinated alkanes (e.g., perfluorohexane) or perfluorinated ethers to dissolve PFSA. Because however, perfluorosulfonic acid polymers have a unique structure with a hydrophobic fluorocarbon backbone and hydrophilic sulfonic acid groups, strictly speaking they do not dissolve. Instead their structure allows them to swell in polar solvents, particularly in water due to the ionic nature of the sulfonic acid groups, thereby forming a gel-like state rather than a clear solution. As such. blending of PFSA and PP in solution is less attractive than mixing the constituent monomers; Moreover, care must be taken to avoid adverse or exothermic reactions and managing the handling of extremely toxic chemicals.

[1700] A more pragmatic solution to synthesize PFSA-PP blended membrane 1090 involves two step process of extruding polypropylene nanofibers using electrospinning and to subsequently lightly crush them into a permanent membrane filler comprising shorter PP snippets or shards. The PP nanofibers are then loaded into a casting mold with PFSA monomers for polymerization. PFSA polymerization is then performed using conventional PFSA membrane synthesis irrespective of the presence of the PP nanofibers.

[1701] Note that because the polymerized PFSA does not chemically bond to polypropylene, the membrane is generally considered a blend and not a copolymer. As such, structural integrity is achieved by ensuring one of the two polymers stoichiometrically dominates the matrix and that the two backbones are intertwined to improve the composite mechanical strength. Since the purpose of the membrane is for ion exchange, it means PFSA should comprise a higher mole fraction of the film than PP, rather than the converse. The resulting structure is essentially a PFSA or PFSA-PTFE polymer including a permanent polypropylene nanofiber filler. This process however does not preclude the use of sacrificial fillers described previously to control ionomer porosity or to employ permanent fillers to enhance conductivity.

[1702] Membrane top view 3000 and membrane side view 3001 in FIG. 126 illustrate a variety of ionomeric polymers 3002 blended with a second polymer comprising polypropylene made in accordance with this invention, including separately or in combination inventive matter comprising: [1703] an ion exchange membrane 3003 comprising two or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1704] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1705] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1706] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1707] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1708] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1709] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1710] where ionomeric polymer 3002 may comprise a copolymer comprising a perfluorosulfonic-acid polytetrafluoroethylene (PFSA-PTFE) mainchain 3009c blended with or bound to backbone 3009b of the polyolefin polypropylene (PP) 3011 as a block copolymer, together controlling film, rigidity, crystallinity, and anisotropy; [1711] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1712] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1713] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1714] A summary of a PP block copolymer is shown reinforcing an exemplary PFSA ionomer.

TABLE-US-00020 ionomer structure endoskeleton solvents, X-L fillers 7. polypropylene blend heterogenous polymer: PP, PE, solv: xylene, TCE, sac filler, CNTs, with ionomeric block PP CRM EPDM, TPO, TPE decalin, tetralin, oxides, POSS, copolymers pillars: reinforcing TCB. NPs, MOFs, PIL PFSA-b-PP fillers (C-fiber, X-L: FFA, BM, PFSA-PTFE-b-PP CNTs) pentane, heptane other polymers-b-PP

[1715] As described, the resulting PP block copolymer constitutes a heterogenous composite reinforced membrane (CRM) of the polyolefin polypropylene and an ionomer polymer of either PFSA or PFSA-PTFE. Although PFSA is provided as an example polymer blend, other polymers may substituted for PFSA in the polypropylene supported matrix. Endoskeletal support can be made for pillar links to the ionomeric backbone. Bonding an endoskeleton to the polypropylene, although more difficult, can be achieved using polyethylene (PE) especially if pretreated with a corona or plasma to increase surface energy; ethylene-propylene-diene monomers (EPDM) with suitable adhesives; direct bonding to thermoplastic olefin (TPO), or thermoplastic elastomers (TPE).

[1716] Polypropylene solvents include aromatic hydrocarbons such as toluene, decalin, or xylene, or with chlorinated solvents such as trichloroethane (TCE) or trichlorobenzene (TCB). Cross linking agents with starting material maleated polypropylene include furfurylamine (FFA), bismaleimide (BM), dichloromethane (DCM), pentane, and heptane. Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

8. Functionalized Polyvinyl Chloride (PVC) Polymer IEMs.

[1717] Motivated by demand for non-fluorinated membranes, the hydrocarbon polyvinyl chloride (PVC) can be functionalized as an ionomer or catalyst, and/or grafted onto a copolymer containing ionomeric or catalytic groups. FIG. 127 illustrates an exemplary process flow for synthesis of sulfonated polyvinyl chloride sPVC 1099. The process combines polyvinyl chloride (PVC) 1094 monomers with ethylenediamine (EDA) to produce blended polymer PVC-EDA 1096 comprising two polymer segments, an amino decorated group of length n and a chlorinated segment of length m. Treating PVC-EDA polymer 1096 with sulfuric acid H.sub.2SO.sub.4 1097 to produce sulfonated polyvinyl chloride sPVC 1099 with pendant attached ionomer 1098. Sulfonated PVC based membranes offer the potential benefits of immunity to H.sub.2O.sub.2 poisoning, excellent physical and chemical robustness, superior stiffness, and low material cost. In addition to fuel cells, PVC applications include sensors for specific metals, as battery separators, and as filters. As articulated, proton conductivity is heavily dependent on relative humidity and film porosity with the hydrophilicity of the sulfonic acid groups is the main driver of water retention within the polymer. Expectedly, membrane synthesis as reported does not address fundamental problematic issues of membrane swelling, mechanical strength, film durability, and cathodic reaction rates.

[1718] By integrating inventive features of this application, the ionomeric performance of sPVC polymers can be greatly enhanced. These elements include (a) sacrificial fillers to control film porosity and conductivity, (b) endoskeletal support to improve film strength and durability and to reduce swelling, (c) nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) occurs, and (d) doping with fillers and PILs to enhance bulk conductivity in the film.

[1719] Polyvinyl chloride can also be functioned by grafting to another ionomeric or catalytic polymer. For example, PVC can be grafted onto polyl-vinyl-3-butyilimidazolium (PVC-g-p(VBIm)) ionomers by reacting it with 1-bromobutane and 1-vinylimidazole via quaternization to yield the monomer I-vinyl-3-butyl-imidazolium bromide, subsequently polymerized into P(VBIm) prior to grafting onto PVC. Polyvinyl chloride copolymer membranes such as PVC-g-p(VBIm) are especially beneficial in performing chemical separation and purification, e.g. separating CO.sub.2 from CH.sub.4.

[1720] In summary membrane top view 3000 and membrane side view 3001 in FIG. 128 illustrate a variety of elements of an ionomeric polymer 3002 comprising poly vinyl chloride (PVC) made in accordance with this invention, including separately or in combination inventive matter comprising: [1721] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1722] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1723] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1724] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1725] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1726] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1727] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1728] where ionomeric polymer 3002 may comprise the polyolefin polyvinyl chloride (PVC) as a mainchain optionally blended or cross-linked to other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; or may include grafts to ionomeric or catalytic polymers and ionic liquids such as polyvinyl chloride grafted to polyvinyl butylimidazolium (PVC-g-P(VBIm)); [1729] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1730] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1731] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1732] The following table summarizes construction of sulfonated poly vinyl chloride (PVC) membrane:

TABLE-US-00021 ionomer structure endoskeleton solvents, X-L fillers 8A. sulfonated heterogenous polymer: PVC, ABS, PC, solv: DMSO, NMP, sac filler, CNTs, polyvinyl chloride PVC polymers PU, PE, PP, TPE, PMMA, THF, DMAc, CHN, oxides, POSS, sPVC & copolymers EPX, PVDF, SBR ace, CPN. NPs, MOFs, PIL 8B. grafted polyvinyl pillars: reinforcing X-L: GA, STMP, CA chloride fillers (C-fiber, CNT) SHMP. PVC-g-p(VBIm)

[1733] The sulfonated polyvinyl chloride polymer comprises a heterogenous membrane comprising a chlorinated segment and a methylated segment with a corresponding pendant and attached ionomer. PVC forms pillar links amendable to bonding to a spectrum of endoskeletal materials including PVC pillars using PVC adhesives; acrylonitrile butadiene styrene (ABS) using solvent cements or applicable adhesives; polycarbonate (PC) using PVC-PC adhesives, polyurethane (PU) using PU adhesives and sealants; polyethylene (PE) using specialized adhesives can create a bond to low-energy PE surfaces; polyvinylidene fluoride (PVDF) with appropriate surface treatment; or to polypropylene (PP) pillars using molecular glues able to bond polar and non-polar materials. Other endoskeletons bondable by adhesives such as epoxy resins (EPX) may comprise thermoplastic elastomers (TPEs), poly(methyl methacrylate) (PMMA), and styrene-butadiene rubber (SBR).

[1734] Solvents used in preparing PVC may include dimethyl sulfoxide (DMSO); 1-methyl-2-pyrrolidinone (NMP); N,N-dimethylacetamide (DMAc); tetrahydrofuran (THF); high concentration acetone (ace), cyclohexanone (CHN), and cyclopentanone (CPN). PVC cross linking agents include glutaraldehyde (GA), sodium trimetaphosphate (STMP), sodium hexametaphosphate (SHMP), and citric acid (CA). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

9. Functionalized Polyimide (PI) Polymer IEMs.

[1735] Another membrane capable of ionomeric conduction is the homopolymer polyimide. FIG. 129 illustrates a process flow for synthesis of a polyimide polymer membrane combining 2,2-bis[4-(4-aminophenoxy)-phenyl] propane (BAPP) 1110 with 4,4-diaminodiphenyl ether-2,2-disulfonic acid (ODADS) 1112 and 4,4-bisphenol-A dianhydride (BPADA) 1111 to produce sulfonated polyamide (PI) 1113. The PI mainchain comprises two portions a phenolated dianhydride segment 1115 of length y and a sulfonated portion 1114 of length x containing sulphonic acids 1116a and 1116b. The unit length (x+y) of mainchain 1113 is then repeated m times to define the total polymer length of each distinct chain in the membrane. The conductivity of sulfonated polyimide (sPI) can be temporarily enhanced by doping with a protic ionic liquid. Without the inventive features of the endoskeleton and membrane nanocoating described herein, however the IL will lek out.

[1736] As an alternative implementation, FIG. 130 illustrates an exemplary process flow for synthesis of a polyimide polymer membrane by combining an aromatic sulfonamide such as sulfonated 1,4-bis(4-aminophenoxy)benzene (pBABTS) 1120 with diamine 1121 and dianhydride 1222 to produce sulfonated polyamide (PI) 1125. As depicted diamine 1121 is an amine with precisely two amino (H.sub.2N) groups sandwiching a divalent radical R.sub.1 such as a para-phenylene group. Diamine is commonly used an a monomer in polymer reactions. Dianhydride 1222 is a polymeric curative comprising two anhydride groups surrounding a central radical R.sub.2, which can vary for any number of organic reactive ligands.

[1737] The combined mix of diamine, dianhydride, and aromatic sulfonamides is then treated by triethylamine TEA (Et.sub.3N chemically as (C.sub.2H.sub.5).sub.3N) followed by treatment in benzoic acid (C.sub.6H.sub.5COOH) and m-cresol aka 3-methylphenol (CH.sub.3C.sub.6H.sub.4(OH)) to produce sulfonated polyimide sPI 1125. The resulting sulfonated polyimide comprises polymer segment 1124 of length y containing radicals R.sub.1 and R.sub.2 and aromatic sulfonamide portion 1123 of length x containing radical R.sub.2 plus multiple instances of attached sulfonic acid groups SO.sub.3H. This chain construction benefits from a high degree of sulfonation and associated high conductivity without compromising the polymer's structural integrity. Chemical reagents and polymerizing agents in this process include triethylamine (TEA), benzoic acid, and m-cresol aka 3-methylphenol.

[1738] Variants of the three constituent moieties shown in FIG. 131 comprise exemplary molecules for polyimide membrane synthesis categorized into three moietiessulfonamides, diamines, and dianhydrides. Sulfonamide candidates include 4,4-diamino diphenylether-2,2-disulfonic acid (ODADS) 1112 or sulfonated 1,4-bis(4-aminophenoxy)benzene (pBABTS). Diamine R.sub.1 candidates include 1,4-bis(4-aminophenoxy-2-sulfonic acid) benzenesulfonic acid (BAPP) 1110, 2,7-bis(4-aminophenoxy) naphthalene (BAPN) 1130, and 4,4-(9-fluorenylidene) (9FDA) 1131. Dianhydride R.sub.2 choices include naphthalene-1,4,5,8-tetracarboxylic dianhydride (NTDA) 1132, 4,4-oxydiphthalic anhydride (ODPA) 1133, and 3,3,4,4-diphenylsulfone tetracarboxylic dianhydride (DSDA) 1134.

[1739] Various processes exist for synthesizing sulfonated polyimide sPI with protic ionic liquid composite membranes. The published membrane synthesis as reported does not address or anticipate fundamental problematic issues plaquing IEMs and PEMs including IL leakage, membrane swelling, mechanical strength, film durability, and cathodic reaction rates. By integrating the inventive features of this application, the ionomeric performance of sulfonated PI polymers can be greatly enhanced.

[1740] These elements include (a) sacrificial fillers to control film porosity and conductivity, (b) endoskeletal support to improve film strength and durability, reduce swelling and prevent ionic liquid leakage, (c) nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) occurs, and (d) doping with fillers and PILs to enhance bulk conductivity in the film.

[1741] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 132 illustrate a variety of elements of a polyimide (PI) ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising [1742] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1743] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1744] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1745] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1746] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1747] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1748] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1749] where ionomeric polymer 3002 may comprise the polyolefin polyimide (PI) 1113 as a mainchain optionally blended or cross-linked to other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1750] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1751] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1752] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1753] Construction elements of a polyimide (PI) based membrane are listed in the table below including descriptions of the ionomer, endoskeleton, solvents, and fillers.

TABLE-US-00022 ionomer structure endoskeleton solvents, X-L fillers 9. sulfonated polyimide heterogenous polymers: EPX, PI, solv: DMAc, NMP, sac filler, CNTs, ODADS, pBABTS sPI homo- PTFE, PEEK, PAm CH.sub.2Cl.sub.2, DMF, THF, oxides, POSS, BAPP, BAPN, 9FDA polymer pillars: reinforcing DMSO NPs, MOFs, PIL NTDA, ODPA, DSDA fillers (C-fiber, CNTs) X-L: see solvents

[1754] As detailed above, a sulfonated polyimide membrane comprises a heterogenous polymer composed of functional radicals including the sulfonamides 4,4-diamino diphenylether-2,2-disulfonic acid (ODADS) and sulfonated 1,4-bis(4-aminophenoxy)benzene (pBABTS); diamines (R.sub.1), of 1,4-bis(4-aminophenoxy-2-sulfonic acid) benzenesulfonic acid (BAPP), 2,7-bis(4-aminophenoxy) naphthalene (BAPN), and 4,4-(9-fluorenylidene) dianiline (9FDA); and dianhydrides (R.sub.2) of naphthalene-1,4,5,8-tetracarboxylic dianhydride (NTDA), 4,4-oxydiphthalic anhydride (ODPA), and 3,3,4,4-diphenylsulfone tetracarboxylic dianhydride (DSDA).

[1755] Endoskeletal materials able to bond to polyimide support pillars include epoxy resins EPX, polytetrafluoroethylene (PTFE) subject to surface treatment, polyether ether ketone (PEEK) using select high-temperature adhesives, or polyamide (PAm, nylon) using suitable adhesives able to bond to both polymer types. The role of solvents in fabricating polyimide is to enable a reaction between a dianhydride and a diamine under ambient conditions using a dipolar aprotic solvent. Examples include such as N-methylpyrrolidinone (NMP), m-cresol, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dichloromethane (CH.sub.2Cl.sub.2), dimethyl sulfoxide (DMSO), and to a lesser extent tetrahydrofuran (THF). Polymerization of PI involves reacting a dianhydride and a diamine at ambient conditions in a dipolar aprotic solvent, so that no specific polymerizing or cross linking agent is required other than the solvents present in synthesis. Membrane fillers and dopants were described previously and for brevity's sake, will not be repeated here.

10. Functionalized Polystyrene (PS) Polymer IEMs.

[1756] Pure polystyrene, i.e. polystyrene (PS) homopolymers represent a class of polymers that is an amorphous thermoplastic that is rigid, brittle and relatively hard with poor chemical resilience. To improve its mechanical and temperature performance, PS is often cross linked to itself or used to form copolymers with other polymeric materials.

[1757] To better understand the need and benefit of cross linking and copolymerization, we must first consider what are the various constructions of homopolymers, cross linked homopolymers, and copolymers. In the lexicology of polymers, a homopolymer is a linear chain of homogenous monomers bound together during the process of polymerization. In contrast, a copolymer is a polymer that is made of two or more monomer species. The polymer is bound to its copolymer counterpart through chemical bonding which may involve another polymer serving as a bridge or through a organic ligand generally involving covalent bonds.

[1758] For long chains, copolymer bonding may also comprise hydrogen bonds which gain strength through a large number of interchain electrostatic attraction points. As a subtle point, the process of concurrently forming bonds between multiple polymeric chains during formation of a homopolymer is referred to as polymerization, whereas the process of forming bonds between multiple dissimilar polymeric chains during film formation is called copolymerization. By contrast, the bonding of a polymeric to another or to another portion of the same chain is referred to as cross-linking.

[1759] As such, cross linked chains may bond multiple chains of the same material, of dissimilar materials, or may form loops on its own chain. Although cross linking may occur during polymerization or be performed subsequent to synthesizing the polymer, as a matter of semantics reagents causing cross chain bonding during polymerization are referred to polymerizing agents while those used to cause cross linking after polymerization are commonly referred to a cross linking agents. For simplicities sake, herein we use terms of polymerizer and cross-linker (X-L) as interchangeable, to be understood in the context of the reaction being discussed.

[1760] To clarify FIG. 133A illustrates a comparison of homopolymer, copolymer, and angled copolymer molecules. As depicted in case (a), homopolymer-A 1135a comprises a single homogenous polymer of a specific chemistry with attached side groups pendants and ionomers 1136. The sidechains are not considered as polymers despite oftentimes comprising nearly the same composition as the mainchain. In case (b), a portion of polymer-A 1135a is interrupted by polymer-B 1137 which is in line with polymer-A, i.e. forming a linear topography. In case (c), the bonding angle of copolymer-C 1138 differs from that of polymer-A 1135a causing the direction of the polymer to break off angle from the mainchain. Despite having different angles, both case (b) and (c) represent linear copolymers.

[1761] By contrast, FIG. 133B illustrates multi-chain copolymers, where the second polymer does nor interrupt polymer-A but instead cross links to it. In case (d), two identical homopolymer strings 1135a and 1135b each comprising polymer-A having respective ionomers 1136a and 1136b are linked by copolymer-B 1137x which serves to cross-link the two polymer-A strands. In case (e), two dissimilar strands polymer A 1135a with ionomer 1178a and copolymer B 1137b with ionomer 1136c are bridged by cross linked ligand 1139a.

[1762] FIG. 133C illustrates in case (f) where a cross linking ligand 1139b forms a loop to its own mainchain polymer 1135a. In case (g) ionomer 1136x forms a bridge between two portions of a common chain 1135a. In some instances as shown in case (h) chain-to-chain bonding can be accomplished by sharing a common ionomer 1136y between polymer A 1135a and copolymer B 1137c. Depending on the specific ionomer performing chain-to-chain bridging, cross linking ionomer 1136y may lose the ability of ionomeric conduction and charge transport offered by ionomers 1136a and 1136c.

[1763] Given the forgoing, FIG. 134 illustrates a process flow for fabricating sulfonated heteropolymer polystyrene (PS) involving either a conventional method or a high mole-fraction sulfonic acid synthesis. In one exemplary process comprising a ultra-high density of sulfonic acid monomers comprising styrene 1140 and divinylbenzene 1141 are polymerized with polystyrene and cross linkages 1143. During sulfonation to attach acids 1144 to the polystyrene, the PS chain is broken into snippets comprising PS fragments 1142f with or without cross linker 1143.

[1764] In an alternative process styrenesulfonate 1145, a styrene monomer is combined together with divinylbenzene 1141 then polymerized with poly(styrenesulfonate) 1142p, where the poly(styrenesulfonate) contains protected sulfone groups 1145p and on-chain bridging 1143. In the final step, the protected sulfone groups 1145p are functionalized, i.e. deprotected, forming sulfonic acid groups 1145a thereby transforming cross-linked poly(styrenesulfonate) 1142p into cross-linked poly(styrenesulfonic acid) 1142a.

[1765] FIG. 135A illustrates an alternative process flow for fabricating a sulfonated heteropolymer polystyrene in the form of cross-linked styrenesulfonate. In steps (a), N-butyl styrenesulfonate (BuSS) 1150c, a styrene monomer, is formed from sodium 4-styrenesulfonate (NaSS) 1150a dissolved in an aqueous solution of AgNO.sub.3 producing silver p-toluenesulfonate (AgTS) 1150b. The compound is the treated by acetonitrile (MeCN, methyl cyanide) resulting in n-butyl styrenesulfonate (BuSS) monomer 1150c containing a sulfonic group 1151s and butyl group 1151b.

[1766] In the second stage shown in steps (b) n-butyl styrenesulfonate monomer (BuSS) 1150c is first treated with azobisisobutyronitrile (AIBN) and dodecyl-dimethyl-acetic-acid)-trithiocarbonate (DDMAT) to form the intermediary compound N-butyl 4-styrenesulfonate (NBuSS) 1150d then dissolved in sodium hydroxide (NaOH) and a blend of tetrahydrofuran (THF) and ethanol (EtOH) and after stirring in a solution of HCl in ethanol, subsequently precipitated. The precipitate, a homopolymer poly(styrenesulfonic acid) (PSSA) 11150e includes sulfonic acid homopolymer 1151s.

[1767] Alternatively, steps (c) in FIG. 135B illustrates formation of a cross-linked copolymer of styrenesulfonic acid. As shown the process involves starting with the polystyrene monomer butyl styrenesulfonate (BuSS) 1150c mixed with divinylbenzene 1153, then polymerized with azobisisobutyronitrile (AIBN) and dimethyl sulfoxide (DMSO) to produce the cross-linked polymer poly(N-butyl 4-styrenesulfonate) (XL-P(BuSS)) with a mainchain 1150g, sulfonic ionomer 1151s, and butyl group 1151b. Subsequent processing with tetrabutylammonium hydroxide (TBA-OH) and 50 C. dimethyl sulfoxide (DMSO) followed with hydrochloric acid (HCl) to form polymeric precipitates cross-linked poly(styrenesulfonate acid) PSSA copolymers 1150h with ionomer 1151h.

[1768] Published works on polystyrene polymeric membrane synthesis do not however address or anticipate fundamental problematic issues plaquing IEMs and PEMs including membrane swelling, mechanical strength, film durability, and cathodic reaction rates. By integrating the inventive features of this application, the ionomeric performance of sulfonated PS polymers can be greatly enhanced. These elements include (i) sacrificial fillers to control film porosity and conductivity, (ii) endoskeletal support to improve film strength and durability and to reduce swelling, (iii) nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) occurs, and (iv) doping with fillers and PILs to enhance bulk conductivity in the film.

[1769] Membrane top view 3000 and membrane side view 3001 in FIG. 136 illustrate a variety of elements of polystyrene ionomeric polymers 3002 made in accordance with this invention, including separately or in combination inventive matter comprising [1770] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1771] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1772] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1773] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1774] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1775] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1776] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1777] where ionomeric polymer 3002 may comprise the thermoplastic heteropolymer polystyrene (PS) as a mainchain optionally blended or cross-linked to other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1778] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1779] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1780] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1781] The following table describes various components of a polystyrene ionomeric film:

TABLE-US-00023 ionomer structure endoskeleton solvents, X-L fillers 10. sulfonated heterogenous polymers: PS, ABS, PC, solv: DVBz, DMSO, sac filler, CNTs, polystyrene PS polymer & PVC, PU, PE, PMMA, ace, toluene, ethyl oxides, POSS, SPS X-L copolymers PET, PAm, TPE EPX. acetate, THF, DCM NPs, MOFs, PIL PSSA pillars: reinforcing fillers X-L: DVBz, DBPO XL-PSSA (C-fiber, CNTs) HMeBnCl

[1782] A heterogenous sulfonated polystyrene (PS) membrane as described comprises a sulfonated polystyrene (SPS) polymer, poly(styrenesulfonic acid) PSSA; and crosslinked (X-L) styrenesulfonate acid (PSSA). Endoskeletal materials compatible for bonding with PS include polystyrene (PS); acrylonitrile butadiene styrene (ABS), a similar polymer easily bonded by cyanoacrylate or acrylic-based adhesives; polycarbonate (PC), easily bonded to polystyrene using adhesives such as polystyrene cement, epoxy, or solvent-based adhesives; polyvinyl chloride (PVC) bonded by adhesives like cyanoacrylates, epoxies, or solvent-based adhesives; polyurethane (PU) bonding to polystyrene via polyurethane-based adhesives or other compatible glues; poly(methyl methacrylate) (PMMA, acrylic) bonded to polystyrene using solvent-based adhesives that can slightly dissolve the surface of both polymers, creating a strong bond as the solvents evaporate.

[1783] Other endoskeletal materials include polyethylene terephthalate (PET), bondable to PS sing adhesives that are compatible with both materials, such as certain epoxies or UV-curable adhesives; polyamide (PAm, nylon) bondable using adhesives like epoxy or with the aid of a primer that can enhance the adhesion between the two polymers; thermoplastic elastomers (TPE) using glue compatible with both materials. More difficult skeletal material candidates to bond include polyethylene (PE) and polypropylene, both of which require prebonding treatments such as radiation or plasmas to induce damage sites for dangling bonds or defects on which PS can attach.

[1784] Solvents for polystyrene include most organic solvents including divinyl benzene (DVBz), dimethyl sulfoxide (DMSO), acetone (ace), toluene, ethyl acetate, tetrahydrofuran (THF), and dichloromethane (DCM). Cross linking agents for PS synthesis include p-hydroxymethyl benzyl chloride (HMe-BnCl), divinyl benzene (DVBz), and dibenzoyl peroxide (DBPO). Membrane fillers and dopants were described previously and for brevity's sake, will not be repeated here.

11. Functionalized Poly Fluorenyl Ether Ketone Nitrile (PFEKN) Polymer IEMs.

[1785] Another homopolymer, poly (fluorenyl ether ketone nitrile) P(FEKN) is a candidate for high temperature fuel cell applications, especially for operation over 80 C. Although sulfonated poly (fluorenyl ether ketone nitrile) polymers have been used to form low equivalent weight P(FEKN) membranes via one-step polycondensation from commercial raw materials, their measured electrical and mechanical properties were not competitive to other IEM polymers and limited to only high temperature operation.

[1786] FIG. 137 illustrates the chemical structure of sulfonated poly (fluorenyl ether ketone nitrile) 1160. As a heteropolymer, the main contains two moieties, one sulfonated the other un-sulfonated. Specifically segment 116n of length n contain a four-benzene crosslinked compound 4,4-(9-fluorenylidene)diphenol (BPFL) 1161n and a linearly attached benzonitrile group 1164, i.e. an aromatic hydrocarbon molecule consisting of a benzene ring functionalized by a cyano (CN) group with an equivalent formula C.sub.6H.sub.5CN. The benzonitrile group 1164 is responsible for the nominative nitrile in the polymer's name.

[1787] The second segment 1162s of length m represents the sulfonated group in the heterogenous polymer. Specifically it comprises another BPFL groups 1161s attached to an ether-ketone group 1165 to which two SO.sub.3H ionomers 1163a and 1163b attach. The total length (m+n) of a unit cell contains eleven aromatic hydrocarbon rings largely responsible for controlling the porosity of the cell. Conventional P(FEKN) membrane synthesis does not address or anticipate fundamental problematic issues plaguing their use in IEMs and PEMs including membrane swelling, mechanical strength, film durability, and cathodic reaction rates. By integrating the inventive features of this application, the ionomeric performance of sulfonated P(FEKN) polymers can be greatly enhanced. These elements include (a) sacrificial fillers to enhance film porosity and conductivity, (b) endoskeletal support to improve film strength and durability and to reduce swelling, (c) nanoparticle coating to improve interfacial reaction rates, especially on the cathode side where the slower oxygen reduction reaction (ORR) occurs, and (d) doping with fillers and PILs to enhance bulk conductivity in the film. None of these features are anticipated in any reported studies.

[1788] Membrane top view 3000 and membrane side view 3001 in FIG. 138 illustrate a variety of elements of ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising [1789] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1790] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1791] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1792] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1793] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1794] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; and/or [1795] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1796] where ionomeric polymer 3002 may comprise the thermoplastic heteropolymer poly(fluorenyl ether ketone nitrile) 1160 as a mainchain optionally blended or cross-linked to other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1797] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1798] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H, carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; [1799] where the combination of the endoskeletal pillars and the membrane coating seal in any ionic liquid doping to prevents seepage, leakage, or IL depletion; and finally [1800] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1801] Features of sulfonated poly fluorenyl ether ketone polymers are described in the table below:

TABLE-US-00024 ionomer structure endoskeleton solvents, X-L fillers 11. sulfonated poly heterogenous polymers: PEEK, solv: DMAC, sac filler, CNTs, fluorenyl ether ketone FEKN polymer PPS, PI, TPU. BHPF, DMSO oxides, POSS, nitrile pillars; reinforcing X-L: DHPhthal NPs, MOFs, PIL sPFEKN fillers (C-fiber, CNTs)

[1802] As described sPFEKN is a heteropolymer comprising a sulfonated chain of fluorenylidene diphenol groups bridged by alternating benzonitrile and ether-ketone groups. Endoskeletal compositions compatible with bonding to the membrane include polyether ether ketones (PEEK), polyphenylene sulfide (PPS), polyimide (PI), and thermoplastic polyurethane (TPU). Solvents include reagents similar to those used with PEEK and PEK films including N-dimethyl-acetamide (DMAC), bisphenol fluorene (BHPF), and dimethylsulfoxide (DMSO). Cross linking agents include 2-dihydro-4-(4-hydroxyphenyl)-1(2H)-phthalazone (DHPhthal). Membrane fillers and dopants were described previously and for brevity's sake, will not be repeated here.

12. Functionalized Polyphenylene (PPh, PP) Polymer IEMs.

[1803] Another broad class of polymers amenable to synthesis of non-fluorinated ion exchange membrane membranes is polyphenylene. Polyphenylenes are macromolecules which comprise benzenoid aromatic nuclei directly joined to one another by CC bonds. As a hydrocarbon based polymer, polyphenylene exhibits a number of beneficial material and electrical qualities. For example, one member of the chemical family, poly (p-phenylene) (PPhP, PPP) can be transformed from an electrical insulator into an electrical conductor or ionomer by doping with electron acceptors or donors. Polyphenylene ether (PPhE, PPE) is noted for its ability to survive temperatures of 320 C. or higher without melting making it a good prospective candidate for high temperature fuel cells.

[1804] It should be noted while it is common practice to abbreviation polyphenylene by the acronym PP, this terminology is identical to the abbreviation for another polymer, polypropylene. As such, throughout this patent unless specifically identified as an exception or contained in an exhaustive list of terms, the acronym PP shall mean polypropylene and the acronym PPh shall mean polyphenylene. This nomenclature is consistent with the convention that phenyl is ofttimes denoted as Ph in chemical formulas to distinguish it from phosphorus P.

[1805] FIG. 139 illustrates the chemical structures of heteropolymer precursors for polyphenylene synthesis including poly(p-phenylene 2,5-disulfonic acid) (PPhDSA, PPDSA) 1166, poly(p-biphenylene 3,3-disulfonic acid) (PBPhDSA, PBPDSA) 1167, poly(p-benzoyl-1,4-phenylene) also referred to as sulfonated sidechain polyphenylene 1169 (sPPh, sPP), and poly[(p-biphenylene 3,3-disulfonic acid)-co-(p-phenylene 2,5-disulfonic acid)] (BXPhY, BXPY).

[1806] FIG. 140 illustrates one possible process flow for fabricating sulfonated polyphenylene heteropolymers comprising two PPh moieties, namely (a) poly(benzoyl-1,4-phenylene, and (b) poly(p-phenoxybenzoyl-1,4-phenylene). Synthesis starts with dichlorobenzophenone-R having the chemical composition C.sub.13H.sub.8Cl.sub.2OR where R is a radical comprising either hydrogen or phenolate ions. The starting material is then treated by reagents bis(triphenylphosphine) nickel(II) dichloride (NiCl.sub.2(PPh.sub.3).sub.2); sodium iodide (NaI); triphenylphosphine (PPh.sub.3); zinc (Zn); and dimethylacetamide (DMAc) at 80 C.

[1807] The process results in a precursor molecule poly(p-phenylene)-phenyloxide-R (PPPh-PhOR) where phenyloxide-R represents an attached sidechain (SC) of a phenol-oxide bound to the radical R. In case (a), treatment of PPPh-PhOR 1171 with sulfuric acid (H.sub.2SO.sub.4) resulting in the sidechain polymer poly(benzoyl-1,4-phenylene)SC-sP(BnPh) 1172. Alternatively, PPPh-PhOR 1171 treated with sulfuric acid blended with trimethylsilyl chloride (TMSiCl, TMSCl) results in an extended sidechain polymer poly(p-phenoxybenzoyl-1,4-phenylene) (SC-sP(PhBnPh)) 1173.

[1808] FIG. 141 illustrates the process flow for fabricating the heteropolymer sulfonated polyphenylene quaterphenol (SPPh-QPh) 1176 comprising sulfonic acid ionomer 1179 constructed from monomers sulfonated phenol (SPh) and quaterphenol (QPh) 1175. FIG. 142 depicts a sulfophenylated polyphenylene (sPhPPh) 1180a as a comprising a generic heteropolymer with sulfonic acid (SO.sub.3H) ionomers 1180 and radical groups 1182.

[1809] For radical R=H.sup.+(Ph) 1184a, the resulting linear polymer is sPhPPh-H.sup.+ or alternatively as sPPP-H.sup.+. For radical R=H.sup.+(NPh) 1184b, the resulting non-linear polymer is sPhPPh-NH.sup.+ or alternatively sPPP-NH.sup.+. For radical R=H.sup.+(BPh).sub.p=H.sup.+(BPh) 1184c, the resulting para-biphenyl polymer is sPhPPh-(B.sub.pPh)H.sup.+or alternatively sPPP-(B.sub.pPh)H.sup.+. Continuing in FIG. 143, with radical RH.sup.+(TPh) 1184d the resulting sulfonated polyphenylene triphenol polymer is sPhPPh-(TPh)H.sup.+ or alternatively sPPP-(TP)H.sup.+. For a meta-biphenyl radical R=H.sup.+(BPh)m 1184e, the resulting sulfonated polyphenylene biphenyl polymer is sPhPPh-(BPh).sub.mH.sup.+ or alternatively as sPPP-(BPh).sub.mH.sup.+. For an ortho-biphenyl radical RH.sup.+(BPh).sub.o 1184f, the resulting sulfonated polyphenylene biphenyl polymer is sPhPPh-(BPh).sub.oH.sup.+or alternatively as sPPP-(BPh).sub.oH.sup.+.

[1810] Other radicals R 1182 shown in FIG. 144 include various Y configured groups of four benzene aromatic rings comprising a center and three branches. Sterically hindered pyridine moieties can be categorized by the replacement of carbon with nitrogen either on the center aromatic ring or the branches therefrom. For example, sPhPPh N-free 1185a is absent any N substitutions, while (0+1)N moiety 1085b has only a center nitrogen, (1+1)N moiety 1085c has N located on the center ring and one branch, (3+0)N moiety 1085d has nitrogen on the branches but not in the center, and (3+1)N moiety 1185e has every ring populated by one nitrogen substitution.

[1811] In another variant, FIG. 145 illustrates a branched polyphenylene matrix 1080b with a specified degree of branching DB and sulfonic acid groups 1181 with radical R 1182. In the example shown R comprises a (0+1)N moiety 1185b in branched polyphenylene polymers containing sterically hindered pyridines. Functionalizing a phenylated polyphenylene (PhPPh) heteropolymer 1180p with sulfonic groups 1181v using a Diels-Alder process is depicted in FIG. 146 resulting in sulfonated Diels-Alder polyphenylene (sDAPPh) 1180v. An alternative process shown in FIG. 147 employs tetra(para-sulfonated) triethylammonium bistetracyclone salt (TEAsBTC) 1179 treated sequentially by (a) PhNO.sub.2, (b) 2M NaOH, and (c) 0.5M H.sub.2SO.sub.4 at 180 C. to form sulfonated hydrated phenylated polyphenylene (sPhPPh-H.sup.+) 1180w with ionomers 1181w.

[1812] FIG. 148 comprises a process flow for synthesis for hydroxylation of sulfonated phenylated polyphenylene (sPhPPh-H.sup.+) 980c into hydroxylated sulfonated-phenylated polyphenylene (sPhPPh-OH) 982z. FIG. 149 depicts various processes for synthesizing biphenyldisulfonic acid. The method of step (a) involves diazotization of 4,4-diamino-2,2-biphenyldisulfonic acid (Di(BPh)S) 1185 into 4,4-diiodo-2,2-biphenyldisulfonic acid (Dil(BPh)S) 1186 by treatment with treated with sodium nitrate (NaNO.sub.2), hydrochloric acid (HCl), and potassium iodide (KI), a polyphenylene precursor with iodide terminus and sulfonic ionomers 1187. Sulfonic acid ionomer 1187 remains unchanged in both reactant and product chemistries.

[1813] In an alternative method of case (b) the process involves halogenation of un-sulfonated reactant 4,4dibromobiphenyl (DiBr(BPh)) 1288 into 4,4dibromo-3,3biphenyldisulfonic acid (DiBr(BPh)S) 1189 during which sulfonic ionomer 1187 is attached to the polymer. In FIG. 150 sulfonic ionomers 1187 present on either (Di(BPh)S) 1186 or (DiBr(BPh)) 1288 is reacted to replace hydrogen with radicals 1189, 1191, or 1192 forming ionomer SO.sub.3R 1187t. FIG. 151 comprises other variations in sulfonated polyphenylene sidechains.

[1814] FIG. 152 depicts yet another process for synthesis of sulfonimide branched poly(phenylenebenzophenone)s (SI-P(PhBnPn)) polymer 1196 from a Y-configured branched phenyl compound 1995 with phenyl sidechains.

[1815] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 153 illustrate a variety of elements of polyphenylene (PPh) ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising: [1816] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1817] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1818] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1819] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1820] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1821] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post casting by a solvent leaving a hole in its place of the sac-filler; [1822] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1823] where ionomeric polymer 3002 may comprise the thermoplastic heteropolymer polyphenylene (PP) as a mainchain optionally blended or cross-linked to other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1824] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1825] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid groups SO.sub.3H including variants sP, sPP, PPDSA, sPP-QP, sPPP-H.sup.+, sPPN-H.sup.+, sPPB-H.sup.+, sPPT-H.sup.+, sPPBm-H.sup.+, sPPBo-H.sup.+, sPPP-OH, sPPP N-free, sPPP (X+0)N, sPPP (X+1)N, BXPY, sPPP, DiBPS, DiPS, DiBrBS, and Si-PPBP; using the abbreviated acronyms where P may denote poly or phenyl; [1826] where ionomeric polymer 3002 may also comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid groups comprising PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte. and finally [1827] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1828] The following table describes the composition of various inventive polyphenylene IEMs:

TABLE-US-00025 ionomer structure endoskeleton solvents, X-L fillers 12. functionalized heterogenous polymers: PPh, solv: CDM, PVDF, sac filler, CNTs, polyphenylene PPh polymer EPX, PUA, SIA, MAA DMF, PEG, NMP, oxides, POSS, PPhDSA, PBPhDSA pillars: reinforcing DMAc, ethanol, NPs, MOFs, PIL sPPh (linear, sidechain, fillers glycol, glycerol, kinked) aliphatic polyols, sPPh-benzoyl MI sPPh-phenoxybenzoyl X-L: heat, sulfur, SDAPP (Diels Alder) peroxide, metal un-sulfonated PPh-R oxides, S donors sPPh-BXPY sidechain SC-sP(BnPh) sidechain SC-sP(PhBnPh) sPPh-QPh/sPhPPh-R +radical R = H.sup.+(TPh) +radical R = H.sup.+(BPh).sub.p +radical R = H.sup.+(BPh).sub.m +radical R = H.sup.+(BPh).sub.o sPhPPh-(DB)H.sup.+ sDAPPh, sPhPPh-H.sup.+ sPhPPh-OH Di(BPh)S-R, DiBr(BPh)S-R sPPh-(X + Y)N sterically hindered SI-P(PhBnPh)

[1829] As listed, polyphenylene (PPh) membranes made in accordance with this invention comprise an expansive list of compounds comprising heterogenous ionomeric polymers. Aside from bonding with itself, PPh can bond with a variety of endoskeletal materials including epoxy resins (EPX), polyurethane adhesives (PUA) especially post surface preparation, silicone adhesives (SiA), and modified acrylic adhesives (MAA). PPh solvents include dichloromethane (CDM), polyvinyl difluoride (PVDF), dimethylformamide (DMF), polyethylene glycol (PEG, PEO), N-methylpyrrolidone (NMP), N,N-dimethylacetamide (DMAc), ethanol, glycol, glycerol, aliphatic polyols, and diiodomethane (methylene iodide, MI). Cross linking occurs with heating, sulfur, peroxides, metal oxides, and with sulfur donors. Membrane fillers and dopants were described previously and for brevity's sake, will not be repeated here.

13. Functionalized Polyarylene Ether (PAE) Polymer IEMs.

[1830] Another class of hydrocarbon based membranes comprise fluorine-free compounds made of the homopolymer polyarylene ether, a high performance thermoplastic with high glass transition temperatures noted for its robust mechanical properties, exceptional thermal stability, and superior chemical resistance. Conventional uses for PAEs include water purification, electrolysis, and ion exchange. PAEs comprise a mainchain featuring alternating rigid aromatic rings and flexible ether bonds, facilitating its high temperature performance and resilience to acid and alkali corrosion, solvent resistance, and oxidative stability. PAE membranes can also be further multi-functionalized to resist contamination from metal ions, microorganisms, bacteria, and other pollutants.

[1831] They may be subcategorized by their different functional groups, namely poly(arylene ether sulfone) (PAES, PAESf) containing sulfone segments in the mainchain; poly(arylene ether ketone) (PAEK) containing ketone segments in the mainchain; and poly(arylene ether nitrile) (PAEN) bonding cyano groups on its sidechain. PAEs are chemically related to polyether ether ketones (PEEK), polyethersulfones (PESf), and poly(arylene ether nitrile)s (PEN) considered elsewhere in this application.

[1832] FIG. 154 comprises one representative process flow for synthesis of the heteropolymer polyarylene ether (SPAE) from 4,4(hexafluoroisopropylidene) diphenol (BPHF) 1202, 4,4-(9-fluorenylidene) diphenol (BPFL) 1200, and decafluorobiphenyl (DFBP) 1202. Blended with C.sub.6H.sub.5CH.sub.3 and CH.sub.3CON(CH.sub.3).sub.2 the reactants were polymerized at 150 C. into a mainchain comprising two segmentssegment 1203a of length x comprising BPFL 1200p and DFBP 1201, and segment 1204 of length y containing BPHF 1202 and DFBP 1201. BPFL 1200p differs from its precursor BPFL 1200 only by polymerization and by conversion of OH groups into bound oxygen.

[1833] During subsequent functionalization with a radical R of hydrogen ions H.sup.+ or sulfonic acid SO.sub.3H, segment 1203 is transformed into equal length 1203r by converting BPFL 1200p into radical functionalized group 1200r by attaching the acidic groups onto the aromatic rings. All other groups remain unchanged. The functionalization may be performed in a number of ways, one of which involves sulfonation using a 12 h treatment at 15 C. in HSO.sub.3Cl and CH.sub.2Cl.sub.2 while incorporating phosphotungstic acid and graphene oxide to enhance conductivity.

[1834] Alternatively various monomers can be polymerized into a sulfonated polyarylene ether sulfone (SPAES) using processes composite membranes containing poly(2,5-benzimidazole)-grafted graphene oxide. Specifically, FIG. 155 comprises process flow for synthesis of the heteropolymer sulfonated polyarylene ether (SPAES) from 4,40-difluorodiphenyl (BFDPS) 1211; 4,4-dihydroxybiphenyl (BP) 1210; and 3,30-disulfonated-4,40-difluorodiphenyl sulfone (SDFDPS) 1212. Processing of the reactants requires the application of N-methyl-2-pyrrolidone (NMP) and toluene at 150 C. for 5 h in step (a), followed by K.sub.2CO.sub.3 for 48 h at 190 C. in step (b). The resulting sulfonated polyarylene ether sulfone (SPAES) comprises two identical moietiesa non-functionalized segment 1213 of length x and a sulfonated component 1214 comprising ionomers SO.sub.3X of length t where the combined length 1215 of (x+y) is repeated n times.

[1835] FIG. 156 comprises the process flow for synthesis of the heteropolymer sulfonated polyarylene ether (SPAES) perfluoropolyether grafted graphene oxide (PFPE-GO) 1219 from graphene oxide (GO) 1218 and fluorinated surfactant Krytox-157 FSL 1212. Synthesis of PFPE-GO involves the treatment of graphene oxide by surfactants such as Krytox-157 FSL comprising a terminal fluoromethylene group of poly(hexafluoropropylene oxide) to enable grafting of fluorocarbon pendants onto GO substrate 1219. As such, the sidechain includes both terminal fluorine and a hydroxide terminus for GO bonding forming PFPE-GO 1219. For example a sulfonated poly(arylene ether sulfone) polymer may form a composite hybrid membrane with perfluorosulfonic acid and doped with perfluoropolyether (PFPE) grafted graphene oxide (GO) to enhance conduction.

[1836] Alternatively FIG. 157 comprises the chemical structural depiction of exemplary heteropolymer sulfonated polyarylene ether (SPAESf) incorporating phosphotungstic acid (PWA) into crystalline clusters 1223 bonded to graphene oxide (GO) substrate 1220. Dangling bonds comprise HO.sub.2 1221 and O 1222 enabling the SPAESf to facilitate bonding to other polymers in a membrane.

[1837] FIG. 158 is a chemical representation of sulfonated polyarylene ether sulphone (sPAES) illustrating the polymer mainchain contains two segments. In segment 1225 of length y includes the linear copolymer of a sulfone and hexafluoroisopropylidene diphenol with no ionomeric functionalization. Segment 1224 by contrast contains a functionalized sulfone segment with radical R attached to available sites on its aromatic rings, where the radical R may comprise a hydrogen ion (H.sup.+) or phenyl-bound sulfonic acid (SO.sub.3H) group.

[1838] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 159 illustrate a variety of elements of ionomeric polymer 3002 of polyarylene ether (PAE) compounds made in accordance with this invention, including separately or in combination inventive matter comprising: [1839] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1840] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1841] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1842] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1843] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1844] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [1845] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1846] where ionomeric polymer 3002 may comprise the thermoplastic heteropolymer polyarylene ether (PAE) as a mainchain 1224 optionally blended or cross-linked to other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1847] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1848] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [1849] where ionomeric polymer 3002 may include ionic fillers including perfluoropolyether (PFPE) grafted graphene oxide 3010; [1850] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte and finally [1851] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1852] The following table describes various structural elements of the SPAE class of membranes:

TABLE-US-00026 ionomer structure endoskeleton solvents, X-L fillers 13. sulfonated poly heterogenous polymers: PAE, PS, HIPS, solv: NMP, DMAc, sac filler, CNTs, (arylene ether)s PAE polymers PAm, PEs, PU, ABS, DMSO, DMF, PEG, oxides, POSS, sPAE pillars; reinforcing fillers DGMME NPs, MOFs, PIL, sPFPE (C-fiber, CNTs) X-L: DT, SDT, PFPE PFPE-GO sPAESf

[1853] The various sulfonated polyarylene ethers comprise heterogenous polymers of non-fluorinated sPAE, fluorinated sPFPE, and sulphone based sPAES. Endoskeletal materials compatible with bonding to PAEs include polystyrene (PS) and high-impact polystyrene (HIPS) which share the styrene moiety in the backbone of poly(arylene ether)s; polyamides (PAm, nylon) using appropriate adhesives or surface treatments; polyesters (PEs) using compatibilizers or coupling agents containing carboxyl or anhydride groups to enhance interfacial adhesion; polyurethanes (PU) using adhesives or by interpenetrating polymer networks (IPNs) by synthesizing PU in the presence of PAE; and acrylonitrile butadiene styrene (ABS). Solvents for s(PAE)s include N-methylpyrrolidone (NMP), N,N-dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), dimethylformamide (DMF), polyethylene glycol (PEG, PEO), and diethylene glycol monomethyl ether (DGMME). Cross linkers include dithiol (DT), sulfonated dithiol (SDT), and bishydroxy perfluoropolyether (PFPE). Aside from PFPE-GO crystallites described in the section, membrane fillers and dopants described previously have been omitted for the sake of brevity, and will not be repeated here.

14. Functionalized Poly Ether Ketone (PEK) Polymer IEMs.

[1854] A special category of polyarylene ether is a class of non-fluorinated thermoplastics heteropolymers referred to as polyether ketones. Collectively referred to as PEK or PEEK these polyether ketones contain any number of ether and ketone groups assembled on a polymer mainchain in varying stoichiometries and sequences. Polyether ketones (PEKs) including polyether ether ketone (PEEK) are formed by the dialkylation of bisphenolate salts, i.e. a process that adds two alkene groups onto the phenylated salt using step-growth polymerization.

[1855] Constructed by a linear polymeric chain of covalently bonded phenyl groups, the resulting semicrystalline matrix exhibits superior mechanical properties and chemical resistance even at elevated temperatures. Aside from mechanical applications of plastics, polyester ketones have chemical applications membrane such as solid polymer electrolysis (SPE) and as proton exchange membranes in fuel cells.

[1856] The basic process for forming a polyether ketone is illustrated in FIG. 160 where three organic components comprising ketone 1231, an aromatic hydrocarbon ring referred to as aryne group 1232, and ether group 1230 are polymerized into polyether ether ketone (PEEK) 1233. These constituent reactants are manifest in the chemical PEEK product. As a matter of definition, a ketone group comprises a carbon-oxygen double bond (CO) is bound to two radical groups R while an ether group comprises a carbon-oxygen single bond (CO) also bound two radical groups R. Chemically as C.sub.6H.sub.4R.sub.2, an aryne group comprise an aromatic ring bond to two radicals R. PEEK 1233 as depicted comprises three aryne groups 1232a-to-1232c, ether groups 1230a and 1230b, and ketone group 1231a. In polyether ketone heterogenous polymers, the aryne group serves as the bridge between the ketone and ether groups. Specifically aryne 1232b serves as radical R.sub.1 for ketone 1231a and as radical R.sub.2 for ether 1232b together forming the polyether ketone mainchain. Clarification on the somewhat confusing naming conventions for ether-ketone molecules are described in the online website victrex.com.

[1857] Although nascent poly ether ketones are electrical insulators, the polymers area readily functionalized by sulfonic groups to become proton specific ionomeric conductors. FIG. 161 illustrates sulfonating poly ether-ether ketone (PEEK) with hydrosulfuric acid H.sub.2SO.sub.4, the process converting the homopolymer PEEK 1233 into a heteropolymer comprising a non-sulfonated chain segment 1233n of length y with ether group 1230n, ketone group 1231n, and aromatic ring aryne 1232n; and with sulfonated chain segment 1233r of length x with ether group 1230r, ketone group 1231r, and aromatic ring aryne 1232r; and with sulfonic acid 2014 attached to one of the aromatic rings in the sulfonated chain segment 1233r. In some instances nanosulfonated silica may be blended into a SPEEK/SPVDF-HFP to enhance its conductivity.

[1858] FIG. 162 illustrates various moieties of polyether ketone molecules depending on the synthesis sequences employed. For example in 1998 research at Virginia Tech, aromatic polyketones were fabricated from soluble precursors derived from bis(a-amininitrile)s. Other organic precursors may also be employed resulting in PEK molecular variants. In exemplary moieties, sulfonated polyether ketone (sPEK) 1236q comprises a single ether 1230q, a single ketone 1231q, and two aryne groups 1232q, one functionalized by radical R where radical R may comprise a hydrogen ion H.sup.+, sulfonic acid SO.sub.3H, or sodium sulfite NaSO.sub.3. Sulfonated polyether ether ketone (sPEEK) 1236r, shown previously as sulfonated segment of heteropolymer sPEEK 1235r in FIG. 161, comprises a two ethers 1230r, a single ketone 1231r, and three aryne groups 1232q, one which is functionalized by radical R. Sulfonated polyether ketone-ketone (sPEKK) 1236s comprises one ether 1230s, two ketones 1231s, and three aryne groups 1232s, one which is functionalized by radical R.

[1859] FIG. 163 illustrates sulfonated polyether ether-ether ketone (SPEEEK) 1236t comprising three ethers 1230t, one ketone 1231t, and four aryne groups 1232t, one which is functionalized by radical R. Sulfonated polyether ether ketone-ketone (SPEEKK) 1236u comprises two ethers 1230u, two ketones 1231u, and four aryne groups 1232u, one which is functionalized by radical R. In another variant, sulfonated polyether ketone-ketone-ketone (SPEKKK) 1236v comprises one ether 1230v, three ketones 1231v, and four aryne groups 1232v, one which is functionalized by radical R. In yet another variant, FIG. 164 illustrates sulfonated polyether ketone ether ketone-ketone (sPEKEKK) 1236w comprising two ethers 1230w, three ketones 1231w, and five aryne groups 1232w, one which is functionalized by radical R.

[1860] FIG. 165 illustrates the polymerization of 4,4-dichlorobenzophenone (C.sub.13H.sub.8Cl.sub.2O, DBP-Cl, DClBzP) 1237 with sodium carbonate (Na.sub.2CO.sub.3, washing soda) catalyzed by diphenyl sulfone and SiO.sub.2CuCl.sub.2 to produce sulfonated poly ether ketone (sPEK) 1236q comprising one ether 1230q, one ketone 1231q, and two aryne groups 1232q, the same polymer as depicted in FIG. 162.

[1861] FIG. 166 illustrates the polymerization of reactants cyclic 4,4-dihydroxybenzophenone (DBP-H, DHBzP) 1238 and 4,4-difluorobenzophenone (DBP-F, DFBzP) 1239 with dimethylacetamide (DMAc) and potassium carbonate (K.sub.2CO.sub.3) to produce a non-conductive intermediary polymer 1240. Polymer 1240 is subsequently functionalized by diluted H.sub.2SO.sub.4 to produce a sulfonated (poly ether ketone)-co-(poly ether ketone) (sPEK-co-PEK, 2PEK) polymer 1236z. As shown, the heterogenous polymer 1236z comprises two ether groups 1230z, two ketone groups 1231z, and four aryne groups 1232z.

[1862] FIG. 167 illustrates one method to fabricate sulfonated polyether ether ketone (sPEEK) 1236r by combining 4,4-difluorobenzophenone 1241 with phenylated trimethylsulfonium (Me.sub.3SO)Bn 1242 in the presence of cesium fluoride (CsF). As described previously, sulfonated polyether ether ketone (sPEEK) 1236r is a heterogenous polymer comprising two ether groups 1230r, one ketone 1231r, and three aryne groups 1232r.

[1863] FIG. 168 illustrates an alternate process for forming sulfonated polyether ether ketone (sPEEK) 1236r by combining reactants 4,4-difluorobenzophenone 1241 and benzene-1,4-diol (hydroquinone) 1243 together with reagents dimethyl sulfoxide (DMSO, (CH.sub.3).sub.2SO) and potassium carbonate (K.sub.2CO.sub.3) to produce a non-conductive intermediary polymer 1244. The intermediary is then converted into an ionomer by treatment in triflic acid (TFSA, CF.sub.3SO.sub.3H). As described previously, the chemical product sulfonated polyether ether ketone (sPEEK) 1236r is a heterogenous polymer comprising two ether groups 1230r, one ketone 1231r, and three aryne groups 1232r.

[1864] FIG. 169 illustrates yet another process for forming sulfonated polyether ether ketone (sPEEK) 1236r by combining reactants benzene-1,4-diol (quinol, hydroquinone) 1243 and phenylated Schiff base of 4,4-difluorobenzophenone (Ph-DFBzP) together with reagents potassium carbonate (K.sub.2CO.sub.3) and N-methyl-2-pyrrolidone (NMP) to form intermediary moiety 1246, a SPEEK precursor. Subsequent treatment in hydrochloric acid (HCL) and N-methyl-2-pyrrolidone (NMP) produces sulfonated polyether ether ketone (sPEEK) 1236r comprising two ether groups 1230r, one ketone 1231r, and three aryne groups 1232r.

[1865] Membrane top view 3000 and membrane side view 3001 in FIG. 170 illustrate a variety of elements of ionomeric polymer 3002 comprising polyether ketone complexes made in accordance with this invention, including separately or in combination inventive matter comprising: [1866] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1867] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1868] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1869] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1870] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1871] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [1872] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1873] where ionomeric polymer 3002 may comprise the thermoplastic heteropolymer in the class of poly(ether ketones) 1235s as a mainchain including sulfonated polymers sPEK, s2PEK, s(iPEK), sPEEK, s(iPEEK), s(iPEKK), s(iPEEKK), s(iPEEEK), or s(iPEKEKK); optionally blended or cross-linked to other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1874] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1875] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [1876] where ionomeric polymer 3002 may include ionic fillers (not shown); [1877] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1878] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1879] The following table describes various structural elements of the PEK and PEEK class of membranes:

TABLE-US-00027 ionomer structure endoskeleton solvents, X-L fillers 14. sulfonated poly heterogenous polymers: PEK, PEEK, solv. HNO.sub.3, HF sac filler, CNTs, (ether-ketone)s PEEK polymer PEI, PAI, PAm, PPhS, PU, H.sub.2SO.sub.4, ClPh, DCM, oxides, POSS, sPEK, sPEKK EPX, adhesives (silicone, C.sub.13H.sub.8O, THF, ace NPs, MOFs, PIL sPEEK cyanoacrylates), PTFE X-L: AlCl.sub.3-DCE sPEEK-PEEK pillars: reinforcing fillers K.sub.2CO.sub.3-DCE, HQu, sPEEEK, sPEEKK (C-fiber, CNTs) PhOBnCl-DMAc sPEKKK, sPEKEKK sPEK-PEK (s2PEK)

[1880] The prior table describes the construction of various polyether ether ketone IEMs made in accordance with this invention. Comprising various combinations of ether and ketone groups, the family of heterogenous polymers collectively referred to as PEK or PEEK, may include one-to-three ether groups and one-to-three ketone groups in varying numbers and sequences. Endoskeletal compositions compatible with bonding to polymeric blends of ethers and ketones may include polyetherimide (PEI), polyamide-imide (PAI), and polyphenylene sulfide (PPhS) using high temperature or interlocking adhesives; epoxy resins (EPX); polyurethanes (PU) and cyanoacrylates for lower temperature operation; and with proper pretreatment of the endoskeletal pillars with adhesives comprising silicone and modified acrylics.

[1881] Composite reinforced poly ether ketone membranes blended with polytetrafluoroethylene (PEEK-PTFE) may also bond to PTFE pillars. Alternatively, glues may be used to attach poly ether-ketone based membranes to poly ether-ketone pillars. such as PEK and PEEK. All PEK-PEEK family polymers can be functionalized by sulphonic acid, as denoted by a lowercase prefix s whereby sulfonated PEK is denoted as sPEK, sulfonated PEEK is denoted as sPEEK, etc.

[1882] Solvents may include nitric acid (HNO.sub.3), sulfuric acid (H.sub.2SO.sub.4), hydrofluoric acid (HF), 4-chlorophenol (C.sub.6H.sub.5ClO, ClPh), 9-fluorenone (C.sub.13H.sub.8O), methylene chloride (DCM), tetrahydrofuran (THF, oxolane), acetone (ace), and hexafluoroisopropyll (HFIP). Cross linking agents of poly ester ketone compounds include sodium borohydride (NaBH), bis(hydroxymethyl) (CH.sub.3O). Polymerization agents and catalysts include aluminum chloride in dichloroethane (AlCl.sub.3-DCE) and 4-phenoxybenzoyl chloride (PhOBnCl, C.sub.13H.sub.9ClO.sub.2) in N,N-dimethylacetamide (DMAc, C.sub.4H.sub.9NO), hydroquinone (HQu, C.sub.6H.sub.6O.sub.2). Membrane fillers and dopants were described previously and for brevity's sake, will not be repeated here.

15. Functionalized Poly Ether-Sulfone/Ketone-Sulfone Polymer IEMs.

[1883] Another related class of heteropolymers is that of polyether sulfones and poly ketone sulfones. This group includes sulfones combined with ether such as polyether ether sulfone (PEES, PEESf); sulfones combined with ketones such as polyketone ketone sulfone (PKKS, PEESf), or sulfones combined with both ethers and ketones such as poly(arylene ketone ether ketone sulfone) (PAKEKS, PAKEKSf). All poly ether/ketone sulfone moieties including PEESf, PKKSf, and PAKEKSf contain aromatic hydrocarbon rings, i.e. benzene rings. Somewhat confusingly, these aromatic groups are explicitly named in some polymers while the name of other polymers neglects to mention their presence. Moreover, when explicitly identified in a polymer's common chemical name, these aromatic rings may be referred to as arylene, aryne, phenyl, or phenylene depending on its bonding and oxidation states.

[1884] In contrast to 14 describing various combinations of ethers and ketones, polymers described in this section all contain a sulfone group, which may be abbreviated as either S or Sf. The abbreviation S is ambiguous and must be taken in context of the polymer containing it. Other S can be mistakenly confused with the symbol for elemental sulfur. Accordingly, sulfone (S, Sf) is an organosulfur compound having the form RS(O).sub.2R where both oxygen atoms form double bonds to the central sulfur atom. As described, sulfone polymer radicals may comprise an ether group, a ketone, group, or an aromatic hydrocarbon ring. In polymers, sulfones confer numerous beneficial material properties including mechanical strength and resistance to oxidation, corrosion, high temperatures, and creep under stress. Direct comparison between ketone and sulfone groups shows no discernable difference or advantage of one over the other in proton exchange membranes.

[1885] In the case of polyether sulfones such as polyether ether sulfone (PEES, PEESf) 1253 described in section 15 A shown in FIG. 171, three functional groups, namely sulfone (RSO.sub.2R) 1251, aryne (C.sub.6H.sub.4R.sub.2) 1252, and ether (RCOR) 1250 are involved in its synthesis. Similar to the poly ether ketones, radicals R of poly ether sulfones may comprise a hydrogen ion H.sup.+, sulfonic acid SO.sub.3H, sodium sulfite NaSO.sub.3, or other ionomeric molecules.

[1886] FIG. 172 illustrates the functionalization of polyether ether sulfone (PEESf, PEES) 1253, an electrical insulating polymer, by the application of sulfuric acid (H.sub.2SO.sub.4) resulting in sulfonated polyether ether sulfone (sPEESf, sPEES) 1253s. This sulfonation process converts PEESf 1253, a homopolymer, into a heteropolymer comprising a un-sulfonated segment 1253n including two ether groups 1250n, a single sulfone group 1251n, and two aromatic rings 1252n into a sulfonated ionomeric segment 1253s containing two ether group 1250s, a single sulfone group 1251s, and a two aromatic rings 1252s with attached SO.sub.3H sulfonic acid ionomer 1054. Various publications consider the formation of sulfonated poly(ether-ether ketone) and sulfonated poly(1,4-phenylene ether-ether sulfone) membranes for use as battery separator films vanadium redox flow batteries. Although they lack the intrinsic characteristics important in fuel cell ionomers, the basic PEESf polymer backbone synthesis is adaptable with suitable changes.

[1887] FIG. 173 illustrates a similar process for sulfonating a single-ether polyether sulfone (PESf, PES) 1290 molecule by treatment in sulfuric acid (H.sub.2SO.sub.4) and chloric acid (ClIO.sub.3H) to produce sulfonated poly ether sulfone (sPESf, sPES) 1291 by attaching sulfonic acid SO.sub.3H 1054 onto one of the polymer's aromatic rings. In other efforts sulfonated polyether sulfone membranes were reinforced with bismuth-based organic and inorganic additives to enhance their structural integrity.

[1888] A PEESf mainchain can also form a copolymer with other polymer types such as poly(ether imide) (PEI) prospectively applicable in direct methanol fuel cells (DMFCs). As shown in FIG. 174, sulfonated polyether ether sulfone (sPEESf, sPEES) 1253s includes two esters 1250s, one ketone 1251s, and three aromatic rings 1252s, one of which attached to sulfonic acid group 1054. In addition to bonding to PEESf chain 1253s, sulfonic acid group 1054 forms a cross linking bond to poly ether imide (PEI) 1254 via a hydrogen bond to a reactive nitrogen in the PEI mainchain. Other nitrogen ions on PEI 1254 chain likewise may connect to other ionomers, in turn linking to other sPEESf chains creating a spider-web of interconnected polymer strands.

[1889] Various synthesis methods for forming poly(ether sulfone)s exist, some facile such as self-polycondensation of AB-type monomers. Other processes are more complex. For example, FIG. 175A the creation of unfunctionalized polyethersulfone (PESf, PES) 1315p starts with a chlorinated or fluorinated biphenyl monomer 4-phenoxyphenyl 1335m treated by potassium carbonate (K.sub.2CO.sub.3) and dimethylacetamide (DMAc) at 160 C. The same process can be used to convert the triphenyl monomer 4-(phenylsulfonyl)phenyl 1336m into unfunctionalized polyether ether sulfone (PEESf, PEES) 1316p. FIG. 175B illustrates the sulfonation of polyethersulfone (PESf) 1315p into sulfonated polyethersulfone (sPESf) 1315s including sulfonic acid 1054 as ionomer.

[1890] More complex copolymerization sequences involve two-step functionalization and cross linking as shown in FIG. 176A. Starting with a sulfonated polyether ether sulfone (sPEESf, sPEES) 1253s homopolymer comprising two ether groups 1250s, one ketone 1251s, and three aromatic rings 1252s and sulfonic group 1054, treatment by sulfur trichloride monoxide anion (SOCl.sub.3) at 70 C. converts the homopolymer into a heteropolymer comprising a sulfonated segment 1253s and a chlorinated segment 1260. Sulfonated segment sPEES 1253s is identical to starting polymer 1253s in composition but shorter in length, reduced from length n to x. The newly chlorinated segment 1260 of length y is modified wherein sulfonic groups 1054 are replaced by sulfurochloridoite (ClO.sub.2) groups 1269, where length y=(nx).

[1891] Subsequent treatment in dimethylacetamide (DMAc) at 60 C. on un-fluorinated hydrocarbon 1261n shown in FIG. 176B results in heterogenous copolymer 1261p comprising sulfonic segment 1253s and modified polymer segment 1260 with pendants 1260z. Sulfonic segment 1252s is identical in composition but shorter in length than starting polymer 1253s, i.e. x<n. Conversely and modified polymer segment 1260 includes a substitution of sulfonic acid SO.sub.3H radicals with another polymeric chain 1260z comprising poly(2-acrylamido-2-methyl-1-propanesulfonic acid).

[1892] The resulting heterogenous polymer 1261p has the chemical name sulfonated poly (1,4-phenylene ether-ether-sulfone)-poly (2-acrylamido-2-methyl-1-propanesulfonic acid) (sP(PhEESf)-PAMPS) where the abbreviation Ph refers to the phenylene group 1252s, Sf refers to the sulfone group 1251s, and S refers to sulfonic acid 1054. One prospective process to form such polymers involves the integration of intercalated poly (2-acrylamido-2-methyl-1-propanesulfonic acid) into sulfonated poly (1,4-phenylene ether-ether-sulfone). Other ether sulfone monomers combine different sulfone reactants to form a longer chain precursor.

[1893] For example in FIG. 177A, reactants bis(4-hydroxyphenyl) sulfone (BHPSU, BHPSf, BHPS) 1310 and bis(4-chlorophenyl) sulfone (BCPSU, BCPSf, BCPS) 1311 are mixed and reacted with potassium carbonate (K.sub.2CO.sub.3) to produce the quarto-phenyl monomer bis-hydroxyphenyl ether sulfone (BHPESf, BHPES) 1312. Subsequent treatment in sulfuric acid (H.sub.2SO.sub.4) converts un-sulfonated polymer bis-hydroxyphenyl ether di-sulfone 1312 into sulfonated polymer bis-hydroxyphenyl ether di-sulfone (sPEDSf, sped) 1312s including sulfonic acid (SO.sub.3H) 1054.

[1894] Another process for creating sulfonated fluorinated polyethersulfone is described in FIG. 178, where isopropyliden diphenyl (BPA) 1270, hexafluoroisopropyliden diphenyl (BPAF) 1271, and 4-flourophenylsulfone (BPSU, BPSf) 1272 are combined with potassium carbonate (K.sub.2CO.sub.3), dimethylformamide (DMF), and toluene to form intermediary polymer chain with segments 1275 and 1276, each fluorinated hydrocarbon compounds but of differing stoichiometric blends. Specifically segment 1275 of length y comprises one sulfone group 1272, one ether group 1250n, and one isopropyliden diphenyl group 1270 but no fluorocarbons. Slightly longer fluorinated segment 1276 of length x contains one sulfone group 1272, two ether groups 1250n, and one hexafluoroisopropyliden diphenyl group 1271. Despite the long length and numerous constituent moieties, the polymer is essentially non-conductive.

[1895] Subsequent treatment in chlorosulfuric acid-allylsilane (ClSO.sub.3SiMe.sub.3) and sodium methoxide (NaOMe) attaches sulfonic acid (SO.sub.3H) 1054 to one of the aromatic rings, converting polymer segment 1275 into an ionomeric polymer segment 1275s while leaving segment 1276 undisturbed. The resulting heterogenous polymer comprising ionomeric segment 1275s of length y and un-sulfonated segment 1276 of length x is referred to herein as sulfonated fluorinated polyethersulfone (sFPESf, sFPES). Such functionalized ionomers also referred to as partially-fluorinated polyethersulfone are in their present implementation applicable for high temperature membranes with minimal swelling, but limited in performance at room temperature.

[1896] An alternative membrane synthesis technique shown in FIG. 179 combining hydroxy-quaterphenyl (4Ph-OH) group 1301 with bis(4-fluorophenyl)sulfone (BFPSU, BFPSf, BFPS) 1303 and bis(4-hydroxyphenyl) sulfone (BHPSU, BHPSf, BHPS) 1302 to produce a heterogenous polymer comprising two segments 1304n of length x and 1305 of length y.

[1897] As shown segment 1304n contains one hydroxy-quaterphenyl (4Ph-OH) group 1301, two esters 1250n, and one sulfone group 1302. In contrast, segment 1305 contains two sulfone groups 1302 and two ethers 1250n. Functionalization by concentrated sulfuric acid (96% H.sub.2SO.sub.4) converts the phenyl groups Ph in hydroxy-quaterphenyl group 1301 to radicals R where is a phenyl group with a sulfonic acid (SO.sub.3H) ionomer. Since ionomeric radical R substitutes three phenyls, a significant change in the conductivity of segment 1304s is manifested. The resulting heterogenous polymer containing sulfonated segment 1304s and un-sulfonated segment 1305 is referred to herein as poly(phenyl ether sulfone) with the acronym sP(PhESf).

[1898] In the context of 15A on sulfonated polyester sulfones sPESf, membrane top view 3000 and membrane side view 3001 in FIG. 180 illustrate a variety of elements of ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising: [1899] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1900] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1901] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1902] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1903] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1904] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [1905] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1906] where ionomeric polymer 3002 may comprise the thermoplastic heteropolymer polyether sulfones including PESf and PEESf as a mainchain 3009c optionally blended or cross-linked 3009x to poly ether imide (PEI) 3009b or other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1907] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1908] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; where ionomeric polymer 3002 may include ionic fillers (not shown); [1909] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1910] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1911] Other related polymers described in section 15B including ketone sulfones and ether-ketone sulfones. As shown in FIG. 181A, 4,4-difluorodiphenylsulfone (DFDPSU, DFDPSf, DFDPS) 1211 when combined with cyanide reactant 1277 and solvents dimethylformamide in nitrogen (DMF-N.sub.2) and sodium hydride NaOH at room temperature, results in intermediary polymer 1278. Subsequent processing in acetic acid (AcOH) and hydrochloric acid (HCl) results in the polymer polyketone ketone sulfone (PKKSf, PKKS) 1279. In FIG. 181B, polyketone ketone sulfone (PKKSf) 1279 is functionalized into ionomeric polymer sulfonated polyketone ketone sulfone (sPKKSf) 1279s by the addition of sulfonic acid 1054.

[1912] FIG. 182A illustrates a reaction of isopropyliden diphenol (BPA) 1270, 1,1-diphenylethylene (DPE) 1271, and 4-flourophenylsulfone (BPSU, BPSf, BPS) 1272 with octafluorocubane (C8F) and N-methyl-2-pyrrolidone (NMP) at 150 C. producing poly (arylene ketone ether ketone sulfone) (PAKEKSf, PAKEKS) comprising segments 1285 and 1286 including esters 1251n, sulfones 1282, and ketones 1280 and 1281.

[1913] Exemplary processes for forming ether-sulfone heteropolymers include forming poly(ether-ether sulfone)s and sulfonated poly(ether-ether sulfone)s derived from functionalized 1,1-diphenylethylene derivatives. The subsequent functionalization of PAKEKSf into an ionomeric polymer by sulfuric acid (H.sub.2SO.sub.4) 1055, comprises sulfonated segment 1286s with ionomer SO.sub.3H and un-sulfonated segment 1285 is shown in FIG. 182B.

[1914] FIG. 183A illustrates an alternative method for synthesizing poly (arylene ketone ether ketone sulfone) (PAKEKSf, PAKEKS) comprising segments 1285 and 1286 from isopropyliden diphenyl (biphenyl A, BPA) 1270; 1,1-diphenylethylene (DPE) 1281, and 4-flourophenylsulfone (BPSU, BPSf, DPS) 1282 including sulphone groups 1282 and 1282x.

[1915] In FIG. 183B treatment by sulfonic acid (SO.sub.3Na) and AIBN at 75 C. for 5 days followed by NMP and DMSO converts un-sulfonated polymeric segment 1285 into sulfonated segment 1285s by converting sulfone group 1282x into a mainchain graft point 1282g thereby attaching ionomeric sulfonic acid (SO.sub.3Na) group 1055. At 5 days processing time, such a method is not commercially viable but does however demonstrate the functionalization of poly (arylene ketone ether ketone sulfone) (PAKEKSf) into sulfonated di-poly (arylene ketone ether sulfone) (sPAKEKSf, s2PAKES).

[1916] Various functionalized ionomeric linear copolymers comprising arylene, ester, ketone, and sulfone groups may also be formed. As depicted in FIG. 184 synthesis of a sulfonated poly(arylene ether ketone sulfone) copolymer (sPAEKSf, sPAEKS) involve the combination of isopropyliden diphenyl (biphenyl A, BPA) 1270; 4,4-dichlorodiphenylsulfone (DCDPhSf, DCDPS) 1511; 4,4-dihydroxydiphenylether (DHDPhE, DHDPE) 1280; and sulfo-4,4-difluorobenzophenone (sDFB) together with dimethyl sulfoxide (DMSO), toluene (C.sub.6H.sub.5CH.sub.3), and potassium carbonate (K.sub.2CO.sub.3).

[1917] The resulting sPAEKSf linear copolymer comprises four segmentsa methylated ester sulfone group 1287a, an ester sulfone group 1287b, a sulfonated methyl ester ketone group 1288s; and a sulfonated methyl ester group 1289s. Ionomeric functionalization is achieved through sulfonic acid (SO.sub.3Na) group 1055 attaching to both sulfonated segments 1288s and 1289s of equal length 0.5x. Un-sulfonated groups 1287a and 1287b each of length 0.5y where x and y need not be equal and where the total length n is thereby the sum of the four segments n=(x+y).

[1918] Dopants may also be introduced into sulfonated poly ether sulfone (sPESf, sPES) membranes to enhance conductivity as depicted in FIG. 185A include nanostructures derived from bismuth(Ill) nitrate pentahydrate (Bi(NO.sub.3).sub.3.Math.5H.sub.2O) 1293, the composition of which may vary by its subsequent chemical processing steps. As shown combining bismuth nitrate 1293 with benzene-1,3,5-tricarboxylic acid (trimesic acid, H.sub.3BTC) 1294 and blending the mix with the catalytic stabilizer dimethylformamide (DMF) for 24 h at room temperature (rt) results in a the nanocrystalline matrix bismuth trimesic acid (BiTMA) 1295. Alternatively, dissolving bismuth nitrate 1293 in isopropyl alcohol (IPA) then blending it with bismuth metal oxide framework (Bi-MOF) 1296 comprising bismuth, molybdenum, sodium, and water for 12 h at 150 C. followed by calcination at 600 C. for 2h to remove the volatile solvents produces the nanocrystal bismuth molybdate (Bi.sub.2MoO.sub.6) 1297.

[1919] As shown in FIG. 185B, these dopants can then be applied to or molded within sulfonated poly ether sulfone 1291 using the solvent N-methylpyrrolidone (NMP) to form the heteropolymer ionomeric membranes, specifically bismuth trimesic-acid-doped sulfonated polyether sulfone (SPESf-BiTMA) membrane 1298 or bismuth-molybdate-doped sulfonated polyether sulfone (SPESf-Bi.sub.2MoO.sub.6) membrane 1299. Embedding bismuth nanoparticles as permanent fillers in ionomeric polymers in accordance with this invention offers benefits in proton conductivity in PEMs by providing additional proton-conducting pathways and/or by modifying the membrane's microstructure to enhance proton mobility. In anion exchange membranes (AEMs) In AEMs, bismuth compounds can enhance ionic conductivity by providing sites that facilitate anion transport with reduced molecular drag.

[1920] Bismuth compounds introduced into the polymer matrix can act as reinforcing agents, improving the mechanical strength and durability of the membrane, a feature particularly important for maintaining membrane integrity under operational stress and high-temperature conditions. The incorporation of bismuth permanent fillers can also enhance the flexibility and toughness of the membrane, reducing the likelihood of cracking or tearing. Bismuth compounds incorporated as nanoparticles also create a more uniform and finely structured membrane matrix, enhancing the dispersion of the fillers and improving the overall performance of the membrane. The incorporation of bismuth compounds into the matrix also invoke changes in the morphology of the membrane, such as pore size and distribution, beneficially influencing the membrane's transport properties and improving its overall efficiency. Bismuth enhances chemical stability, rendering making the film more resistant to degradation by chemical species such as free radicals, acids, or bases. Bismuth compounds can also be included in a nanoparticle coating or embedded into the catalyst layer. For example, made in accordance with this invention the addition of these bismuth compounds into the cathode catalyst layer (CCL) accelerate the oxygen reduction reaction (ORR), the rate limiting reaction in a PEM fuel cell.

[1921] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 186 illustrate a variety of elements of ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising: [1922] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1923] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1924] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1925] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1926] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1927] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [1928] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1929] where ionomeric polymer 3002 may comprise the thermoplastic heteropolymers poly(ether-sulfone) aka sPES or poly(ketone-sulfone) as a mainchain 3009c optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1930] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1931] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [1932] where ionomeric polymer 3002 may include ionic fillers including bismuth trimesic acid (BTMA) 1295 and bismuth molybdate (Bi.sub.2MoO.sub.6) 1297; [1933] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [1934] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[1935] The following table describes various structural elements of the hybrid sulfone class of membranes including ether sulfones, ketone sulfones, and ether-ketone sulfone heteropolymers. Sulfone heterogeneous polymers and copolymers comprising combinations of arylene, ketone, esters, and bismuth and copolymers of ether imide and poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS) collectively comprise a subset of poly(arylene ketone sulfones) and poly(arylene ketone ester sulfones). Numerous ionomer moieties are listed in the table.

[1936] Endoskeletal pillar materials or coatings able to bond to heterogenous sulfone compounds include epoxy adhesives and resins (EPX), polyimides (PI), silicone adhesives, polyurethane (PU), acrylic adhesives, along with other poly arylene ester sulfone, poly arylene ketone sulfone, and poly arylene ester ketone sulfone polymers (PAEKS) and various cyanoacrylates (CAc) including methyl groups (MCA), ethyl groups (ECA), N-butyl (N-BCA), octyl groups). Commonly abbreviated as CA cyanoacrylates herein as referred to as CAc to avoid confusion with citric acid (CA).

TABLE-US-00028 ionomer structure endoskeleton solvents, X-L fillers 15. ether sulfone, ketone heterogenous polymers: EPX, solv: DMSO, sac filler, CNTs, sulfone, ether-ketone sulfone polymers HF-IPS, PAEK, PU, NMP, Bz, xyl, oxides, POSS, sulfone heteropolymers +arylene PI, CAc tol NPs, MOFs, PIL sPESf +ketone pillars: X-L: Bz, BnOH, sPEESf +esters reinforcing fillers DMF, NMP sPEDSf +bismuth (C-fibers, CNTs) sPEESf-co-PEI sulfone sP(PhEESf)-co-PAMPS copolymers sFPESf +ether imide sPKKSf +PAMPS sPAKEKSf (s2PAKES) sPAEKSf SPES-BiTMA SPES-Bi.sub.2MoO.sub.6

[1937] Solvents used in forming ether sulfone and ketone sulfone polymers include dimethylsulfoxide (DMSO), benzene (Bz), xylene (xyl), toluene (tol), hexafluoroisopropyl alcohol (HF-IPA). Solvents and cross linkers used in polymerization include N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methyl pyrrolidone (NMP), and biphenyl A (BPA), benzene (Bz), and benzyl alcohol (BnOH, cresol). Aside from the bismuth crystallites and nanoparticles BiTMA and Bi.sub.2MoO.sub.6 described in the section, membrane fillers and dopants described previously have been omitted for the sake of brevity, and will not be repeated here.

[1938] Although described separately in the previous sections, poly arylene ethers (PAEs) include poly arylene ketones, poly ether ketones, poly ether sulfones, poly ketone sulfones, and poly ether ketone sulfonesall of which include an arylene group. Arylene is a broad class of bivalent radicals (as phenylene) derived from an aromatic hydrocarbons by removal of a hydrogen atom from each of two carbon atoms of the nucleus.

16. Functionalized Hybrid Polymer IEMs with Carbon Fillers.

[1939] In common speech, the term hybrid means the mixing two or more different components in the composition of something. In the lexicon of chemistry and material science, the term hybrid is more definitive, applying both to the nature of chemical bonding and to materials formed therefrom. Specifically in localized valence theory, a hybrid chemical bond comprises atomic orbitals of different yet interacting elements or molecules sufficiently similar to accommodate persistent electrostatic attraction. If the attraction is sufficiently strong and the orbitals reasonably compatible, a chemical bond will result.

[1940] Although all chemical bonds are governed by physics, specifically the laws of electromagnetics defined by Maxwell and Gauss, the type of bond, namely Van der Waals, hydrogen, ionic, or covalent depends on the attractive force between atoms and other factors such as 3D-shape. Specifically if the outer atomic shell of an element is completely filled, the element is generally unreactive, e.g. in the case of group VIII (group 18) noble gasses like neon and xenon.

[1941] In the cases of elements having one fewer or one more electron than a fully filled electronic shell, chemical reactivity in such high electronegative or electropositive elements such as Li, Na, K, and F is significant, often leading to ionic bonds. Fluorine forms especially strong bonds to carbon, which explains the chemical resilience of PTFE. Other factors enabling or preventing hybrid bonds include quantum mechanical effects such as orbital splitting and the Pauli exclusion principle, polar vs nonpolar molecules, and hydrophobicity vs hydrophilicity.

[1942] Hybrid bonding is an especially important factor in forming manmade crystals such as GaAs, GaN, and InP; and in forming hybrid polymers. Specifically in polymer chemistry, a hybrid polymer is a material containing two or more different types of molecules. Hybrid polymers either comprise a copolymer comprising two different polymers bonding by a cross linking molecule such as glutaraldehyde, formaldehyde, etc. Copolymers generally involve independent synthesis of the separate monomers later polymerized into homopolymer strands and subsequently cross-linked to form the homopolymers.

[1943] The separate strands may be arranged linearly on a common mainchain, may form branches off of one another, or may comprise distinct backbones bridged together by cross-linking ligands. If the homopolymer segments are long, the copolymers are referred to as block polymers (discussed later in the application. A heteropolymer by contrast comprises dissimilar monomers polymerized into a heterogenous backbone concurrently, i.e. the monomers are contemporaneously polymerized and linked.

[1944] Another form of hybrid polymer is any homopolymer and heteropolymer doped by a permanent filler such as carbon, silicates, zeolites, tungsten crystals, POSS, MOFs or other additives. Herein, copolymeric and doped membranes are therefore referred to as hybrid polymers. In the context of this invention, a carbon filled membrane is a polymeric membrane containing permanent fillers containing carbon compounds, crystals, and matrices such as pristine graphene, graphene oxides, carbon nanotubes, carbon nanospheres, carbon nanofibers, and other carbon compounds. Other allotropes of carbon include diamond, graphite, ionsdaleite, buckminsterfullerene (C.sub.60), fullerene (C.sub.540 and C.sub.70), amorphous carbon, cyclocarbon, carbon nanobuds, schwarzites, glassy carbon, and linear acetylenic carbon (carbyne).

[1945] Among these, carbon nanotubes (CHTs) represent a highly useful allotrope of carbon comprising hollow tubes made of rolled up sheet of graphene, i.e. single atomic layers of carbon. Shown in FIG. 187 (canatu.com), single wall carbon nanotubes (SWCNTs) comprise a single atomic layer of carbon forming a long hollow tube of hexagonally shaped tiles of carbon. Multi-walled carbon nanotubes (MWCNTs) consist of nested single-wall carbon nanotubes, i.e. concentrically layered as a tube-within-a-tube. As such, multiwalled carbon nanotubes increase the net carbon wall thickness and total nanotube diameter, resulting in a higher surface area of the CNT. For example, a doubling in CNT diameter increases the surface area of the CNT by four times. Double- and triple-walled carbon nanotubes (DWCNT, TWCNT) are common variants of MWCNTs.

[1946] As a material, carbon nanotubes exhibit extraordinary tensile strength, high thermal conductivity, and high durability. Although pure carbon nanotubes is considered a moderate conductor, surface treatment with ionomeric groups and metals can dramatically influence its conductivity much like chemical doping of semiconductors such as silicon can change its conductivity by many orders-of-magnitude.

[1947] Using the classic electronic shell terminology for the periodic table of elements, carbon like silicon is a group 14 (or classically group IV) element, meaning both carbon and silicon contain four valance electrons in a shell requiring eight electrons to complete. Covalent bonding with itself or other group IV elements can result in complete elimination of ionized conduction electrons, making CNT behavior that of a semiconductor. As a semiconductor, minor changes in the concentration of surface dopants can dramatically influence conduction. As such, doping CNTs can greatly enhance conductivity by forming surface bonds easily ionized. For example any bond broken at energies less than the thermal energy kT/q, 0.026 eV at room temperature, releases a free electron into the conduction band contributing to conduction. In this sense, carbon nanotubes electrical conductivity ranges from that of a good conductor to that of a semiconductor. Interestingly, the bandgap of a CNT decreases with its diameter, meaning the larger the CNT, the more conductive it becomes.

[1948] A CNT can also be functionalized by attaching ionomeric or catalytic groups onto its surface. Conversely insulating CNTs can be made through oxidation of carbon surfaces. Functionalization of carbon nanotubes has many diverse uses including electromechanical actuation using ionic polymer metal composite actuators based on sulfonated poly(1,4-phenylene ether-ether-sulfone)-carbon nanotubes. Other processes attach functional groups to the CNT surface. For example, as shown in FIG. 188, single-walled carbon nanotube 1351 treated by a nitric-sulfuric acid (HNO.sub.3H2.sub.SO.sub.4) mixture at 45 C. results in attachment of carbocyclic acid groups (COOH) 1355 onto CNT 1351a. Subsequent sonication of decorated CNT 1351b in aqueous NaOH results in a substitution reaction of hydrogen by sodium ion Na.sup.+ 1356.

[1949] Carbon nanotubes can be used to enhance Nafion membranes by introducing functionalized multiwalled carbon nanotubes into the polymer. As shown in FIG. 189, carbon nanotube 1352 is blended with co-reactant RNNR in 80 C. alkali water at pH=10 and where RR 1357 is a carboxylic acid salt C(CH.sub.3)(CN)CH.sub.2CH.sub.2COO.sup. Na.sup.+) resulting in decorated CNT 1352b functionalized by sodium salt 1358. The ionic terminus can then be replaced by any number of termini.

[1950] Exemplary ionomeric activation of functionalized carbon nanotubes is depicted in FIG. 190 where carbon nanotube 1361 may be functionalized by sulfonic acid (SO.sub.3H) 1363a, carboxyl group (COOH) 1363b, phosphorus hydroxide (POH) 1363c, amino group (NH.sub.2) 1363d, silica or silicate (SiO.sub.2) 1363e, or titania (TiO.sub.2) 1363f. In accordance with this invention, the functionalized carbon nanotubes 1361f may be combined with a variety of polymers 1360 such as PFSA, PFSA-PTFE, sPAESf, sPEEK, sPEESf, PBI, CS and others to form a nanotube doped membrane 1362.

[1951] As such, the inclusion of functionalized or un-functionalized carbon nanotubes into a polymer can affect its mechanical and electrical properties. Nanotubes can also influence film morphology. The diameters of CNTs is measured in nanometers with single walled carbon nanotubes (SWCNTs) having diameters between 0.5 nm to 2 nm. With lengths up to several microns or longer, CNTs can have length-to-width aspect ratios of 4000. Comparable in dimension to long polymers, the presence of long CNTs in a membrane can affect crystallinity, porosity, and fuel crossover. One problem is that CNTs are so small they may be mobile under certain conditions, escaping from the membrane if they are not properly tethered or constrained. One such method is to employ an endoskeleton and membrane nanocoating to constrain their movement in a manner similar to the inventive embodiment herein used to prevent leakage of ionic liquids (ILs).

[1952] Made in accordance with this invention, carbon nanotubes may be used in a variety of beneficial ways in a ionomeric membrane, namely, [1953] as a permanent filler comprising unfunctionalized CNTs added to endoskeletal pillars providing enhance mechanical strength, improved film rigidity, and greater thermal conductivity, [1954] as a permanent filler added to a catalyst layer comprising a catalyst functionalized nanotubes to enhance reaction rates, particularly for cathode side oxygen reduction reactions (ORRs), [1955] as a permanent filler added to an ion exchange membrane comprising a metal or ionomer functionalized CNT to enhance conductivity. [1956] as a permanent filler added to an ion exchange membrane comprising CNTs which together with the application of sacrificial fillers, control the porosity of a ion exchange membrane.

[1957] Aside from the use of carbon nanotubes, graphene oxides (GO) comprise another category of carbon filler beneficial as a permanent filler in an ion membrane. Unlike CNTs which behave as metals or semiconductor depending on doping, graphene oxide function as two-dimensional semimetals. One prospective process for functionalizing GO involves sulfonating poly(arylene ether sulfone) to form a composite membrane with perfluorosulfonic acid containing perfluoropolyether grafted graphene oxide. Graphene oxide may be functionalized 1371 by Krytox-157-FS, a fluorinated surfactant 1370 to produce perfluoro-polyether grafted graphene oxide (PFPE-GO) 1372.

[1958] Another prospective process involves introducing a poly(2,5-benzimidazole)-grafted graphene oxide into proton exchange membrane to enhance conductance. FIG. 192 converts graphene oxide (GO) 1371 through a reaction of polyphosphoric acid (PPA) with diaminobenzoic acid (DBA) to produce poly (2,5-benzimidazole) grafted graphene oxide (ABPI-GO) 1374.

[1959] Another functionalized GO variant comprising poly (3,4-benzimidazole) graphene oxide (ABPI-GO) substrate shown in FIG. 193 involves forming a sulfonated poly(arylene ether sulfone) composite membrane containing poly(2,5-benzimidazole)-grafted graphene oxide. Variations in the molecular structures of graphene substrates shown in FIG. 194 are described in greater detail in a University of Manchester 2016 thesis paper by SI Al-Batty.

[1960] FIG. 195 illustrates the application of GO carbon nanoflakes 1384 in an ion exchange membrane. As shown the interface between the MPL portion of gas diffusion layer 1380 and a PFSA-PTFE reinforced composite membrane 1381 includes an amorphous matrix of 1382 and binding material 1383. Without carbon doping operation of a direct methanol fuel cell involves hydrogen transport 1385 through the electrolyte and into the cathode to facilitate conduction. Unfortunately a portion of fuel comprising methanol (CH.sub.3OH) transported to the interface crossover through the membrane and into the anode as depicted by path 1386x disrupting efficient operation of the fuel cell. Addition of carbon nanoflakes 1384 into binding layer 1383 interferes with methanol transport 1386i resulting in rejection of methanol 1388 at the surface at the PFSA-PTFE membrane 1381. In this manner inclusion of carbon into the catalyst layer or upon the PEM membrane suppresses fuel crossover and improved fuel cell conversion efficiency.

[1961] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 196 illustrate a variety of elements of ionomeric polymers 3002 containing carbon fillers made in accordance with this invention, including separately or in combination with other inventive matter comprising [1962] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1963] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1964] where the pillars comprise a reinforced core 3007 containing carbon fiber, or carbon nanotubes, or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1965] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1966] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1967] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [1968] where an optional nanocoating (not shown) which may include functionalized or catalyst coated carbon nanotubes is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1969] where ionomeric polymer 3002 may comprise any polyolefin or thermoplastic homopolymer or heteropolymer as a mainchain 3009c including PFSA-PTFE, SPAES, SPEEK, SPEES, along with sulfonated PP, PE, PU, PC, PI, PBI or CS optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1970] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [1971] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [1972] where ionomeric polymer 3002 may include ionic fillers including carbon nanotubes 1361 coated with either SO.sub.3H, COOH, POH, NH.sub.2, SiO.sub.2, or TiO.sub.2; and/or graphene oxide GO 1371 including PFPE-GO, ABPBI-GO, Hoffman GO, Scholz-Boehn GO, Ruess GO, or Lerf-Klinowski GO; [1973] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR.sub.4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally, [1974] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion, or loss of CNT fillers added into the matrix.

[1975] The following table describes carbon filled ionomeric and catalytic polymers and membranes:

TABLE-US-00029 ionomer structure endoskeleton solvents, X-L fillers 16. carbon filled heterogenous polymers: matched solv: matched to sac filler, CNTs, polymers carbon filled to IEM ionomer IEM polymer; oxides, POSS, PFSA-PTFE polymers pillars: reinforcing X-L: cross linkers NPs, MOFs, PIL PFSA-PVA-PTFE fillers (C-fibers, CNTs) matched to IEM including CNTs, SPAES, sPEEK, sPEES polymer type GO sPVA PBI, CS

[1976] Unlike previously cited polymers, the addition of permanent carbon fillers is agnostic to the polymer used to form a membrane or to construct the endoskeletal. Instead in accordance with this invention, carbon compounds confer several unexpected benefits including (a) carbon fiber or un-functionalized nanotubes can be embedded into inert pillars to mechanically strengthen the membrane's endoskeletal support, (b) catalyst or scavenger functionalized nanoparticles or carbon functionalized nanotubes as a coating to improve catalytic activity and balance redox reaction rates and/or protect against catalyst poisoning, and (c) permanent fillers comprising functionalized carbon nanotubes and/or functionalized graphene oxides to enhance film conductivity, control film porosity, improve membrane strength, reduce polymer swelling, and manage fuel crossover in DMFCs.

17. Functionalized Hybrid Polymer IEMs with Silica Fillers.

[1977] Although intrinsically not as electrically or chemically active as carbon fillers, silicon based fillers can also be functionalized to improve conductivity while enhancing film strength. Silicon, the most carbon-like element in the periodic table is another group IV element with four filled valance electrons in an eight electron shell. As such, silicon can be processed to form insulators such as amorphous glass and oxides; to form semiconductors comprising a hyper-pure single-crystal ingots, wafers, chips, and nanoparticles; and to form conductors of metal crystallites and quasi-crystals. FIG. 197 illustrates the various morphologies

[1978] A comparison of silicates, i.e. oxidized silicon is available online, e.g. on Britannica website, and through various papers discussing the formation and uses of large-pore mesostructured cellular foam (MCF) silica. The electrical behavior of oxidized silicon compounds is closely related to chemical morphology, structures which include amorphous structures 1401 such as silicon dioxide (SiO.sub.2) 1400; crystalline forms 1403 such as nesosilicates ((SiO.sub.4).sup.4) 1402; and silica MCF 1404 aka mesostructured cellular foam 1406. MCF 1404 particles are considered foam-like as they comprise semi-hollow silica spheroids 1405c with windows 1405w. These spheroids easily bond to hydroxide (OH) outside the spheroid boundary.

[1979] FIG. 198 illustrates the formation of hollow mesoporous silica (HMS) 1408 from silica MCF mesostructured cellular foam (mSiO.sub.2) 1407, subsequently doped by phosphoric acid (H.sub.3PO.sub.4) 1410 to produce phosphorylated hollow mesoporous silica phosphoric acid (HMS-PA) 1409. Morphological features of mesostructured cellular foam of silica may be etched to create hollow centers able to capture catalysts, acids, or ionomeric groups much the same as guest molecules in metal organic frameworks (MOFs).

[1980] A process to functionalize mesoporous silica nanospheres is illustrated in FIG. 199 starting with nascent mesostructured cellular foam (MCF) 1417 with OH surface bonds treated by water (H.sub.2O.sub.2) to produce amino mesostructured cellular foam (MCF-NH.sub.2) 1417a with NH.sub.2 terminus 1418a. Subsequent treatment of (MCF-NH.sub.2) 1417a by (3-aminopropyl)triethoxysilane (APTES) produces hydroxy mesostructured cellular foam (MCF-OH) 1418b with OH terminus 1418b. Treatment of hydroxy MCF 1417b by (3-mercaptopropyl)trimethoxysilane (MPTMS) results in sulfonated mesostructured cellular foam (MCF-SO.sub.3H, MCF-SA) 1417c including sulfonic acid (SO.sub.3H) 1418c. Prospective applications for functionalized MCFs include a variety of polymers including sulfonated poly(ether-ether sulfone)

[1981] FIG. 200 illustrates the role of mesostructured cellular foam (MCF) 1427 in ionomer conduction involving ionomeric hopping conduction. As shown, ionomer backbone 1421 connects to pendant sidechains 1422 with sulfonic acid termini 1423 and nearby mesostructured cellular foam (MCF) 1427. During ionic hopping conduction, proton 1431 bonds to ionomer 1423 then hops to a NH.sub.2 group attached to MCF 1427. The proton next jumps to a second ionomeric sulfonic acid group and the process is repeated. The presence of sulfonated mesostructured cellular foam 1427 particles thereby assist in charge transport by creating more conduction paths involving the MCF not limited to ionomer-to-ionomer hopping.

[1982] By contrast, MCF assisted vehicular transport of protons shown in FIG. 201 comprises the conduction of excess protons in the form of hydronium ions 1432 which may spontaneously revert to hydrogen ions 1431 or vise versa as they traverse the matrix. As depicted H.sup.+ attaches itself to neutral water (H.sub.2O) molecules 1433 to form hydronium ions (H.sub.3O). In pure vehicular transport these hydronium ions may drift through the matrix in response to an electric field of may diffuse as a consequence of a concentration gradient. In hybrid conduction a free hydrogen ion may bond onto ionomer 1423a then detach itself only to ionize another water molecule into hydronium, and repeat the process. In this manner protons alternate between bonding onto immobile ionomers grafted 1429 or attached to polymer backbone 1421a then jumping onto free moving water molecules and transported as vehicular hydronium.

[1983] Because excess protons in the matrix form hydrogen bonds with water (H.sub.2O) molecules shown as dotted lines, the spider-web of hydrogen bonds provides additional structural support to the matrix of ionomers and polymers. For example through this tenuous fluid network, ionomer 1423b indirectly bonds polymer backbone 1421b to polymer backbone 1421a even there is no covalent bonding between the two polymer mainchains. The addition of mesostructured cellular foam 1430 further contributes to the hydrogen bonding network by forming additional hydrogen bonds between water droplets in the matrix and the O.sup. and OH groups present of the MCF's surface. In this manner, the introduction of mesostructured cellular foam 1430 a permanent filler in the membrane helps regulate water sorption and membrane swelling. This mechanism occurs even if the MCF is not functionalized by sulfonic acid, i.e. even if there are no SO.sub.3 groups present on the surface of MCF 1430.

[1984] Note that FIG. 201 shows only vehicular and hybrid transport but neglects cation transport involving MCF sulfonic surface groups shown in the previous figure. In reality both mechanisms of vehicular transport and charge hopping are concomitant, occurring concurrently throughout the ionomer matrix. As such, the introduction of MCF into a ionomeric polymer made in accordance with this invention can regulate hydration, improve film strength, and enhance conductivity. When the permanent MCF viler is combined with the aforementioned sacrificial filler process controlling porosity, the import of a polymer's hydrophobicity on conductivity is diminished.

[1985] The process of doping a membrane involves introducing the MCF into the mold during casting. The morphological and electrical changes to the otherwise undoped pristine ionomer depend on the species of MCF added during synthesis. For example as shown in FIG. 202, the addition of an amino doped mesostructured cellular foam (MCF-NH.sub.2) 1417y to a polymer comprising a sulfonated ionomer such as sPEESf 1253s and un-functionalized ether-sulfone segment 1253n results in a new ionomeric membrane sPEESf-MCF-NH.sub.2 having mechanical and electrical properties neither component offers on its own. Similarly the addition of sulfonated mesostructured cellular foam (MCF-SO.sub.3H) 1417z to sulfonated ionomer sPEESf 1253s results in a new film sPEESf-MCF-SO.sub.3H having a greater density of sulfonic groups 1054 and higher conductivity than sPEESf itself can achieve.

[1986] Silica based mesostructured cellular foam can given the right conditions and adequate time be processed to exhibit self-assembly of macrostructures. As shown in FIG. 203, starting with CTABr1441, the quaternary ammonium surfactant known as cetrimonium bromide with the condensed structural formula (C.sub.16H.sub.33)N(CH.sub.3).sub.3]Br, a spherical micelle template 1442 is synthesized which self assembles 1440 into rod micelles 1443 and ultimately into a lyotropic liquid crystal phase 1442. According to Wikipedia, lyotropic liquid crystals comprise amphiphiles, which are both hydrophobic and hydrophilic, dissolved into a solution that behaves both like a liquid and a solid crystal.

[1987] Made in accordance with this invention include channel-embedded aluminum-substituted mesoporous silica may be used to enhance conductivity in high-temperature anhydrous proton-exchange membrane fuel cells. These self assembled silica crystallites form a mesostructured inorganic solid surfactant composite 1444 which can be further modified by calcination, i.e. heating solids at a high temperature to remove volatile substances or oxidizing a specific amount of mass, to form a honeycomb silicate structure referred to as mesoporous silica 1445. The mesoporous silica is then functionalized by grafting aluminum or other metals onto the substrate to form an isomeric MCF comprising Al-grafted mesoporous silica 1446 as illustrated in the transmission electron micrograph 1447. The aluminum MCF ionomer can then be introduced into a non-fluorinated membrane such as phenylene-bibenzimidazole (PBI) for use in a direct methanol fuel cell (DMFC).

[1988] One such process for Al-MCF doping of PBI is shown in FIG. 204 where 3,3-diaminobenzidene (DAB) 1450 is combined with isophthalic acid (IPA) 1451 in the presence of polyphosphoric acid (PPA) and N.sub.2 at 220 C. to form poly (2,2-m-(phenylene)-5,5-bibenzimidazole) (PBI) 1451. Shown in its pristine form mPBI exhibits a small grain structure 1452. The addition of Al-grafted mesoporous silica cellular foam (Al-MCF) 1446 using a sol-gel process results in a Al-grafted hybrid MCF membrane (mPBI-Al-MCF) having a completely different morphology s shown in the TEM 1453 compared to pristine PBI 1452.

[1989] Doping of PBI with permanent fillers of Al-MCF is important in high temperature fuel cells, i.e. operating above 100 C. to prevent acid leaching from the membranes while limiting fuel crossover. The introduction of an Al-substituted hexagonally ordered mesoporous silica (Al-MCM) channel into poly(2,2-m-(phenylene)-5,5-bibenzimidazole) (m-PBI) membrane markedly enhances the reliability of a PBI membrane. Moreover Al-MCM channels enables a mPBI composite membrane to absorb increased H.sub.3PO.sub.4, thereby improving proton conductivity and high temperature fuel cell performance.

[1990] Membrane top view 3000 and membrane side view 3001 in FIG. 205 illustrate a variety of elements of ionomeric polymer 3002 with silica fillers made in accordance with this invention, including separately or in combination inventive matter comprising: [1991] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [1992] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [1993] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [1994] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [1995] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [1996] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [1997] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [1998] where ionomeric polymer 3002 may comprise any polyolefin or thermoplastic homopolymer or heteropolymer as a mainchain 3009c including PFSA-PTFE, SPAES, SPEEK, SPEES, PI, PE, PC, PBI or CS optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy; [1999] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2000] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2001] where ionomeric polymer 3002 may include ionic fillers including hollow phosphoric acid doped mesoporous silica (HMS-PA) 1409, mesostructured cellular foam (silica MCF) 1417 including MCF-SO.sub.3H, hydroxy MCF, or MCF-NH.sub.2; and Al-grafted mesoporous silica 1446 forming a hybrid membrane with poly (2,2-m-(phenylene)-5,5-bibenzimidazole) aka mPBI; [2002] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2003] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2004] The following table describes the use of silica fillers in a variety of polymeric membranes:

TABLE-US-00030 ionomer structure endoskeleton solvents, X-L fillers 17. silica filled heterogenous polymer: matched solv: matched to HMS-PA, Si-MCF, polymers silica filled to IEM polymer; IEM polymer; MCF-SO.sub.3H, MCF-OH, PFSA-PTFE polymers pillars: reinforcing X-L: cross linkers MCF-NH.sub.2, Al-MCF PFSA-PVA-PTFE fillers (C-fiber, CNTs, matched to IEM sac filler, CNTs, SPAESs, sPEEK, silica, silicates) polymer type oxides, POSS, sPEESf NPs, MOFs, PIL sPVA, CS PBI, PBU-co-Al-MCF

[2005] Heterogenous membranes comprising a variety of polymers doped with hollow phosphoric acid doped mesoporous silica (HMS-PA), mesostructured cellular foam (silica MCF) including MCF-SO.sub.3H, hydroxy MCF, or MCF-NH.sub.2; and Al-grafted mesoporous silica 1446 especially when forming a hybrid membrane with poly (2,2-m-(phenylene)-5,5-bibenzimidazole) aka mPBI. The construction of the endoskeleton and membrane depend on the polymer itself, not on the high temperature capable silica filler. The permanent silica filler may however be combined with the sacrificial filler process described herein to further control conductivity and fuel crossover.

18. Functionalized Hybrid Perfluoro-Methyl-Dioxolane (PFMMD-Co-PFSA) Copolymer IEMs.

[2006] Compared to glassy amorphous membranes made of perfluoro-methylene-methyl-dioxolane (PFMMD) homopolymers described in 3, another approach to forming ionomeric membranes comprises forming a copolymer of PFMMD with perfluorinated sulfonic acid (PFSA). As described previously PFSA films are attached to polytetrafluoroethylene (PTFE) backbone providing mechanical rigidity but limiting gas perfusion by its semi-crystalline morphology. Although PFSA membranes with PTFE polymeric backbones offer good mechanical strength, the ionomer suffers significant mass-transport losses and excessive heating at high currents, thereby limiting its useful power density, especially at low Pt loadings. Replacing PTFE mainchains with PFMMD introduces amorphous areas improving charge transport and enhancing film conductivity.

[2007] An exemplary process to synthesize the amorphous polymer poly(perfluoro-2-methylene-4-methyl-1,3-dioxolane) (PFMMD) made in accordance with a Dupont patent is illustrated in FIG. 206A, where hexafluoropropylene oxide 1500 is treated by benzophenone at 225 C. to form perfluoropyruvyl fluoride (F.sub.3CCOCOF) 1501. Combining the two with cesium fluoride (CsF) to form perfluoro-2-oxo-3,6-dimethyl-1,4-dioxane 1502. Further treatment by CsF at 180 C. forms perfluoro-2,4-dimethyl-2-fluorocarbonyl-1,3-dioxolane 1503, which is converted by sodium carbonate (Na.sub.2CO.sub.3) at 296 C. into perfluoro-2-methylene-4-methyl-1,3-dioxolane 1504, a monomer of PFMMD where RfF. Note that if the radical Rf is replaced with CF.sub.3, the monomer name is changed to PFMDD.

[2008] FIG. 206B illustrates synthesis of a PFMMD copolymer from the combination of methyl 3,3,3-trifluoropyruvate (F.sub.3CCOCOOCH.sub.3) 1505 and chlorinated methyl stereo isomers 1506a and 1506b in dimethyl sulfoxide (DMSO) and potassium carbonate (K.sub.2CO.sub.3) at 0 C. to produce 2-carboxymethyl-2-trifluoro-methyl-4-methyl-1,3-dioxolane 1507. Subsequent treatment in potassium hydroxide (KOH) in a F.sub.2N.sub.2 ambient produce potassium salt 1508 which is readily converted by bis(2-ethoxyethyl) ether at 130 C. into PFMMD polymerizer perfluoro-2-hydro-2,4-dimethyl-1,3-dioxolane 1509.

[2009] FIG. 206C illustrates the polymerization process combining the PFMMD monomer comprising perfluoro-2-methylene-4-methyl-1,3-dioxolane 1504 and PFMMD polymerizer perfluoro-2-hydro-2,4-dimethyl-1,3-dioxolane 1509 in perfluoro-di-tert-butyl peroxide results in perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD) 1512.

[2010] FIG. 206D contrasts variations of perfluoro(methylene-R) dioxolane PF(M.sub.R)D 1510 where the radicals R and R.sub.f may comprise either F or CF.sub.3. As described previously, in the case of perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD) (1512) the radicals RF and RfCF.sub.3. For perfluoro-2-methylene-1,3-dioxolane (PFMD) (1511) both radicals comprise fluorine RR.sub.f=F. Alternatively, for perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PFMDD) 1513, both radicals RRfCF.sub.3.

[2011] FIG. 207 illustrates a process for polymerizing perfluoro(methylene-r) dioxolane monomers into copolymers starting with PFMMD/PFMDD monomer 1504 where for PFMMD, R.sub.fF and for PFMDD RfCF.sub.3. Combining the PFMMD version of monomer 1504 where RfF with the PFMD monomer 1504f forms the copolymer poly(PFMMD-co-PFMD) or in shorthand as P(PFMMD-co-PFMD). The generic structure of the copolymer with radical Rf is labelled as 1513r, while the specific instance where R.sub.fF, i.e. P(PFMMD-co-PFMD) is referred to a 1513p.

[2012] Combining the PFMDD version of monomer 1504 where RfCF.sub.3 with PFMD monomer 1504f forms a structurally related copolymer poly(PFMDD-co-PFMD) 1513r except for the different radical Rf. In shorthand the tri-copolymer is referred to as P(PFMDD-co-PFMD) 1515r. Although the generic structure of the copolymer with radical R.sub.f is labelled as 1513r, the specific instance where R.sub.fCF.sub.3, i.e. P(PFMDD-co-PFMD) is referred to a 1513m.

[2013] Alternatively combining the aforementioned PFMMD version of monomer 1504 where R.sub.fF with chlorotrifluoroethylene (CTFE) 1514 forms the copolymer poly(PFMMD-co-CTFE) 1515r or in shorthand as P(PFMMD-co-CTFE). Combining the PFMDD version of monomer 1504 where RfCF.sub.3 with chlorotrifluoroethylene (CTFE) 1514 forms the copolymer poly(PFMDD-co-CTFE) 1515r or in shorthand as P(PFMDD-co-CTFE). Although the generic structure for both copolymers with radical R.sub.f is labelled as 1515r, the specific instance P(PFMMD-co-CTFE) where R.sub.fF is numbered as 1515p and where the copolymer P(PFMDD-co-CTFE) where RfCF.sub.3 is numbered as 1515m.

[2014] Unfortunately, perfluorodioxolane polymers forming amorphous glassy membranes while good for gas separation, are neither catalytic nor ionomeric and not useful for electrolysis, in dialysis, or in fuel cells. As such, process and structural modifications are necessary to adapt these polymers for electrochemical applications. As shown in FIG. 208, the same PFMMD monomer 1504r with radical R.sub.f can also be combined with a polystyrene monomer such as pentafluorostyrene (PFSt) 1516 to form copolymer poly(PFMD-co-PFSt) 1517r with shorthand notation P(PFMD-co-PFSt), also neither catalytic nor ionomeric. Although the generic structure for both copolymers with radical Rf is labelled as 1517r, the specific instance P(PFMMD-co-PFSt) where R.sub.fF is numbered as 1517p and where the copolymer P(PFMDD-co-PFSt) where RfCF.sub.3 is numbered as 1517m.

[2015] FIG. 209A contrasts PFSA-PTFE heteropolymer 1520 to the PFMMD-co-PFSA copolymer 1530. As shown, PFSA-PTFE heteropolymer 1520 comprises TFE repeated units 1521 and segment 1524 attached to pendant 1522 and ionomer 1523. By contrast, PFMMD-co-PFSA copolymer 1530 includes aromatic fluorocarbon 1531 in repeat segment 1531 with segment 1534 attached to pendant 1532 and ionomer 1533. By replacing TFE units 1521 with aromatic ring 1535, PFMMD-co-PFSA copolymer 1530 provides better gas and charge transport than PTFE based mainchains.

[2016] These benefits of an amorphous are illustrated schematically in FIG. 209B, comparing the two membrane typesthe PFSA-PTFE heteropolymer 1540 and PFMMD-co-PFSA copolymer 1545. In PFSA heteropolymer 1540, ionomeric matrix 1542 comprising a PFSA-PTFE polymeric backbones formed atop catalyst layer 1549 cluster together to form crystalline structures 1544 with gas transport channels 1541 and hydrated channels 1543. In contrast, PFSA-PFMMD copolymer 1545 comprising ionomeric matrix 1547 integrating PMMD polymeric backbones formed atop catalyst layer 1549 do not cluster together to form crystalline structures, but instead form unimpaired gas transport channels 1546 and hydrated channels 1548.

[2017] Shown in FIG. 210, one exemplary process for the synthesis of a PFMMD-co-PFSA involves the combination of PFMMD 1560 with perfluoro(4-methyl-3,6-dioxaoct-7-ene) sulfonyl fluoride (PSVE) 1561. Sequentially, the process combining (a) initiation at 60 C., (b) NaOH at 85 C., and (c) H.sub.2SO.sub.4 at 85 C. results in the linear fluorinated heterogenous copolymer PFMMD-co-PFSA 1564 comprising ionomer 1566 and PFMMD segment 1563. PFMMD used in gas separation membranes may also be blended with perfluoropolyether (PFPE) to form a copolymer PFMMD-co-PFPE (not shown) to enhance the operating temperature range of the membrane.

[2018] Made in accordance with this invention a new class of linear copolymer is described comprising a tri-copolymer of perfluoro (methylene-r) dioxolane copolymers with perfluorosulfonic acid (PFSA). The benefits of the new membranes are numerous. Advantages of the new tri-copolymers include: [2019] compared to other perfluoro (methylene-r) dioxolane (PFMD) homopolymers and copolymers, the new tri-copolymer membranes are ionomeric where PFMDs are not because they contain a conductive sulfonic group 1566 [2020] the ionomeric group in the new tri-copolymer can optionally bond to various catalytic groups including metal-organic frameworks (MOFs) and other permanent fillers rendering the membrane useful for catalysis and filtering, [2021] compared to pristine perfluorosulfonic acid (PFSA), the new membrane is mechanically stronger and less susceptible to swelling and water logging, and [2022] compared to PFSA-PTFE heteropolymers, the amorphous portions of the film offer superior gas transport and higher conductivity than the semi-crystalline portions of a PTFE supported ionomer.

[2023] One variant of the PTFE-free tri-copolymer shown in FIG. 211A comprises a copolymer 1513p consisting of perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD) 1512p and perfluoro-2-methylene-1,3-dioxolane (PFMD) 1511p forming a linear copolymer with perfluorosulfonic acid (PFSA) containing pendant 1561 and ionomer 1566. Although ionomer 1566 is depicted as sulfonic acid (SO.sub.3H), other acids such as phosphoric acid (PA) may be substituted depending of the electrolyte chemistry desired. Together they form a new ionomeric membrane comprising the hybrid tri-copolymer P(PFMMD-co-PFMD-co-PFSA) 1550p offering superior mechanical strength, good porosity, resilience to swelling, and improved conductivity.

[2024] Another variant of the PTFE-free tri-copolymer shown in FIG. 211B includes a copolymer 1513m of perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PFMDD) 1513m and perfluoro-2-methylene-1,3-dioxolane (PFMD) 1511m forming a linear copolymer with perfluorosulfonic acid (PFSA) containing pendant 1561 and ionomer 1566. Although ionomer 1566 is depicted as sulfonic acid (SO.sub.3H), other acids such as phosphoric acid (PA) may be substituted depending of the electrolyte chemistry desired. Together they form a new ionomeric membrane comprising the hybrid tri-copolymer P(PFMDD-co-PFMD-co-PFSA) 1550m offering superior mechanical strength, good porosity, resilience to swelling, and improved conductivity.

[2025] A second category of the PTFE-free tri-copolymers shown in FIG. 211C comprises a copolymer 1515p consisting of perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD) 1512p and chlorotrifluoroethylene (CTFE) 1514p forming a linear copolymer with perfluorosulfonic acid (PFSA) containing pendant 1561 and ionomer 1566. Although ionomer 1566 is depicted as sulfonic acid (SO.sub.3H), other acids such as phosphoric acid (PA) may be substituted depending of the electrolyte chemistry desired. Together they form a new hybrid tri-copolymer ionomeric membrane P(PFMDD-co-CTFE-co-PFSA) 1551p offering superior mechanical strength, good porosity, resilience to swelling, and improved conductivity.

[2026] Another PTFE-free tri-copolymer shown in FIG. 211D comprises a copolymer 1513m of perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PFMDD) 1515m and chlorotrifluoroethylene (CTFE) 1514m forming a linear copolymer with perfluorosulfonic acid (PFSA) containing pendant 1561 and ionomer 1566. Although ionomer 1566 is depicted as sulfonic acid (SO.sub.3H), other acids such as phosphoric acid (PA) may be substituted depending of the electrolyte chemistry desired. Together they form a new hybrid tri-copolymer ionomeric membrane P(PFMDD-co-CTFE-co-PFSA) 1550m.

[2027] A third category of the PTFE-free tri-copolymers is shown in FIG. 211E comprising a copolymer 1517p consisting of perfluoro-2-methylene-4-methyl-1,3-dioxolane (PFMMD) 1512p and pentafluorostyrene (PFSt) 1516p forming a linear copolymer with perfluorosulfonic acid (PFSA) containing pendant 1561 and ionomer 1566. Although ionomer 1566 is depicted as sulfonic acid (SO.sub.3H), other acids such as phosphoric acid (PA) may be substituted depending of the electrolyte chemistry desired. Together they form a new hybrid tri-copolymer ionomeric membrane P(PFMMD-co-PFSt-co-PFSA) 1552p offering superior mechanical strength, good porosity, resilience to swelling, and improved conductivity.

[2028] Another PTFE-free tri-copolymer shown in FIG. 211F comprises a copolymer 1513m of perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PFMDD) 1513m and pentafluorostyrene (PFSt) 1516p forming a linear copolymer with perfluorosulfonic acid (PFSA) containing pendant 1561 and ionomer 1566. Although ionomer 1566 is depicted as sulfonic acid (SO.sub.3H), other acids such as phosphoric acid (PA) may be substituted depending of the electrolyte chemistry desired. Together they form a new hybrid tri-copolymer ionomeric membrane P(PFMDD-co-PFSt-co-PFSA) 1552m.

[2029] Made in accordance with this invention, the tri-copolymers of FIGS. 211A-211F constitute six new polymeric moieties of perfluoro-methylene-dimethyl polymers functionalized into ionomers for electronic applications for which PFMMD and its chemical siblings are incapable. Functionalized ionomeric copolymer described herein comprise any linear copolymer of PFMMD, PDMDD, PFMD, CTFE, and/or PFSt in combination with an ionomer such as PFSA with sulfonic acid, or phosphoric acid, boric acid, or others.

[2030] In summary membrane top view 3000 and membrane side view 3001 in FIG. 212 illustrate a variety of elements of ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising [2031] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2032] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2033] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2034] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2035] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2036] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2037] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2038] where ionomeric polymer 3002 may comprise a perfluoro-2-methylene-4-methyl-1,3-dioxolane (PMMD) backbone 1309c and perfluoro(4-methyl-3,6-dioxaoct-7-ene) sulfonyl fluoride (PFSA) 1009b to form linear methylated copolymer PFMMD-co-PFSA 1564 optionally blended with other homopolymers, heteropolymers, copolymers, including perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PFMDD), chlorotrifluoroethylene (CTFE), and/or pentafluorostyrene (PFSt); thereby controlling varying degrees of film crystallinity and anisotropy; [2039] where the listed copolymers may be used for gas separation irrespective of the inclusion of PFSA in the polymer; [2040] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2041] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; or a phosphoric acid or boric acid group; [2042] where ionomeric polymer 3002 may include ionic fillers (not shown)I; [2043] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2044] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2045] The following table describes various structural elements of the perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PFMDD) and methylene-methyl-dioxolane copolymers (PMMD) backbone class of membranes including perfluorinated sulfonic acid (PFSA), PFMD, chlorotrifluoroethylene (CTFE), and pentafluorostyrene (PFSt) compounds:

TABLE-US-00031 ionomer structure endoskeleton solvents, X-L fillers 18. methylene-methyl- hybrid polymers: PVDF, PU, solv: DMF, HFB, sac filler, CNTs, dioxolane copolymers PFMMD PS, PFMD, PFMMD, DEC, PVA. oxides, POSS, PFMMD-co-PFSA copolymers PMMA, PFMDD. X-L: FBzO, NPs, MOFs, PIL PFMDD-co-PFSA pillars: reinforcing FDTBO, PFDMO. PFMD-co-PFSA fillers (C-filler, CNTs). PFMMD-co-PFMD-co-PFSA PFMDD-co-PFMD-co-PFSA PFMD-co-CTFE-co-PFSA PFMMD-co-CTFE-co-PFSA PFMDD-co-CTFE-co-PFSA PFMD-co-PFSt-co-PFSA PFMMD-co-PFSt-co-PFSA PFMDD-co-PFSt-co-PFSA

[2046] Section 3 describes pristine heteropolymer IEMs of PMMDD and PFSA, whereas the above table describes glassy amorphous hybrid IEMs of composite reinforced membranes comprising copolymers of PFMMD related polymers including PFMMD, PDMDD, PFMD, or any other polymer such as PFSt or CTFE having large groups that interfere with polymer crystallinity. Although any number of endoskeletal materials may be used in pillar construction, molecules of similar composition to the membrane such as PFMD, PFMMD, PFMDD, PMMA, PU, and PVDF offer better bonding strength then hydrophobic perfluorinated materials.

[2047] Exemplary solvents include dimethylformamide (DMF), hexafluorobenzene (HFB), and diethyl carbonate (DEC). During synthesis, cross linking agents include perfluorodibenzoyl peroxide (FBzO).sub.2 or simply FBzO, perfluoro-di-tert-butyl peroxide (FDTBO), and perfluoro-dimethyl-dioxolane (PFDMO). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here. Applications of glassy amorphous membranes of copolymers include gas separation membranes and proton exchange membranes for hydrogen fuel cells.

19. Functionalized Hybrid Phenylenediamine (PDD) Copolymer IEMs.

[2048] Another category of glassy or amorphous copolymers are those related to poly(dioxo-dihydro) compounds. The synthesis of one such compound PDDP-CSFS is shown in FIG. 213 in which chlorsulfonyl isocyanate (CSI, CISI) 1570 is treated for 24b at 85 C. by antimony trifluoride (SbF.sub.3, Swarts' reagent) to produce fluorosulfonyl isocyanate 1571, which is subsequently treated by methylbenzene (MeBz) and triethylamine (TEA) to yield 2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carbonylsulfanoyl fluoride (DDPCSF) 1572.

[2049] Subsequent treatment in stabilizer 1,4-dioxane and benzoyl peroxide (BPO) for 24 h at 80 C. produces the linear copolymer poly(2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carbonyl) sulfonyl fluoride-co-styrene (PDDP-CSF-co-St, PDDP-CSFS) 1574 with sulfonic acid ionomer 1574. In a parallel process shown in FIG. 214, the high-X copolymer 4-(phenylsulfonyl)-1,1-biphenyl (Pmax-100) 1582 containing benzene group 1581 and the orthogonal group sulfone 1582 is converted by fuming in sulfuric acid (H.sub.2SO.sub.4) for 12 h at 45 C. into the sulfonated high-X copolymer 4-(phenylsulfonyl)-1,1-biphenyl (SPmax-1200) 1583 comprising the sulfonated phenyl groups 1581s and 1582s.

[2050] FIG. 215A illustrates a reaction of previously described molecules comprising poly(2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carbonyl)sulfanoyl fluoride-co-styrene (PDDP-CSFS) 1573 including sulfonyl fluoride side group 1574 and high-X copolymer sulfonated 4-(phenylsulfonyl)-1,1-biphenyl (SPMax-1200) 1583, wherein treatment by the organic solvent dimethylsulfoxide (DMSO) at 100 C. in infrared light, a hybrid linear copolymer PDDP-CSFS-co-SPmax 1885 is synthesized as shown by SEM image 1885i. The chemical representation of PDDP-CSFS-co-SPmax 1885 is illustrated in FIG. 215B.

[2051] Membrane top view 3000 and membrane side view 3001 in FIG. 216 illustrate a variety of elements of glassy ionomeric polymer 3002 comprising poly(dioxo-dihydro) and poly(dioxo-dihydro-pyrrole) compounds made in accordance with this invention, including separately or in combination inventive matter comprising: [2052] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2053] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2054] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2055] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2056] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2057] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2058] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2059] where ionomeric copolymer 3002 is a hybrid of PDDP-CSFS mainchain 3009c comprising 2,5-dioxo-2,5-dihydro-1H-pyrrole-1-carbonyl)sulfamoyl fluoride and a highly-branched high-X copolymer 3009b such as Pmax-1200 1580 or SPMax-1200 1583 optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form hybrid copolymer blend 1585; [2060] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2061] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2062] where ionomeric polymer 3002 may include ionic fillers (not shown)I; [2063] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2064] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2065] Whereas section 3 describes pristine heteropolymer IEMs of PDD and PFSA, the characteristics of PDD and PDDP copolymer membranes are described in the below table:

TABLE-US-00032 ionomer structure endoskeleton solvents, X-L fillers 19. phenylenediamine hybrid PDD polymers: PAm, PU, solv: DMF, HFB, sac filler, CNTs, PDD copolymers copolymers PI, aramid fiber, EPX DEC, PVA. oxides, POSS, PDDP-CSFS pillars: reinforcing X-L: FBzO, NPs, MOFs, PIL PDDP-CSFS-co-SPmax fillers (C-fiber, CNTs) FDTBO, PFDMO.

[2066] Copolymer ionomers comprise phenylenediamine linear chains copolymerized with carbonyl-sulfanoyl fluoride, and sulfonated phenylsulfonyl biphenyl monomers. Exemplary solvents include dimethylformamide (DMF), hexafluorobenzene (HFB), and diethyl carbonate (DEC). During synthesis, cross linking agents include perfluorodibenzoyl peroxide (FBzO).sub.2 or simply FBzO, perfluoro-di-tert-butyl peroxide (FDTBO), and perfluoro-dimethyl-dioxolane (PFDMO). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here. Applications of glassy amorphous membranes of copolymers include gas separation membranes and proton exchange membranes for hydrogen fuel cells.

20. Functionalized Hybrid Phenyl Copolymer IEMs.

[2067] Linear chains of phenyl may also be used to form ionomeric copolymers, especially in the form of phenyl-co-alkanes and phenyl-co-aldehydes. An alkane is a molecule incorporating an acyclic, i.e. open chain saturated hydrocarbon, comprising hydrogen and carbon atoms arranged in a tree structure in which all the carbon-carbon bonds are single. In phenyl-co-alkanes linear chain polymers, alkanes form the linkage between various phenyl moieties. For example, in FIG. 217 polymeric precursors include (i) spiro-monomer SBI 1600, (ii) p-dimethoxybenzene 1601, and (iii) p-terphenyl 1602. When reacted with pentafluorophenyl group 1603 in step 1 with acid and dichloromethane (DCM), the products comprise three sulfonated phenyl-alkane polymers with one off-chain fluorophenyl group plus (iv) one on-chain phenyl group 1604, (v) two on-chain phenyl group 1605, and (vi) three on-chain phenyl group 1606. In step 2, the intermediate products are treated with sodium 4-hydroxybenzenesulfonate 1607 followed H.sup.+ annealing.

[2068] As shown in step 3 of FIG. 218 treatment of phenyl-alkane 1604 having one on-chain phenyl by sodium 4-hydroxybenzenesulfonate 1607 followed H.sup.+ annealing results in a sulfonated phenyl-co-alkane SP1 1610 where the sulfonic group attaches to every other fluorophenyl group. Step 4 of FIG. 219 illustrates treatment of phenyl-alkane 1605 having two on-chain phenyl groups by sodium 4-hydroxybenzenesulfonate 1607 followed H.sup.+ annealing results in a sulfonated phenyl-co-alkane SP2 1611 where the sulfonic group attaches to every other fluorophenyl group.

[2069] Step 5 of FIG. 220 illustrates treatment of phenyl-alkane 1606 having three on-chain phenyl groups by sodium 4-hydroxybenzenesulfonate 1607 followed H.sup.+ annealing results in a sulfonated phenyl-co-alkane copolymer SP3 1612 where the sulfonic group attaches to every fluorophenyl group.

[2070] An exemplary process for formation of a phenol sulfonic acid membrane is depicted in FIG. 221 where phenol group 1605 is mixed with sulfuric acid (H.sub.2SO.sub.4) at 80 C. for 3 h to form 4-hydroxy benzene sulfonic acid 1616. The compound is subsequently treated by an aldehyde having the molecular structure R-CHO at 5 C. for 0.5 h followed by 85 C. for 24 h to produce the sulfonated phenyl-aldehyde sPh-CHO 1607. As shown every phenol ring is decorated by sulfonic acid.

[2071] Membrane top view 3000 and membrane side view 3001 in FIG. 222 illustrate a variety of elements of ionomeric copolymers 3002 comprising phenyl mainchains made in accordance with this invention, including separately or in combination inventive matter comprising: [2072] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2073] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2074] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2075] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2076] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2077] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2078] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2079] where ionomeric polymer 3002 is a phenol compound such as phenyl-alkane 1612 or phenol-aldehyde 1617 optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2080] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2081] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2082] where ionomeric polymer 3002 may include ionic fillers (not shown)I; [2083] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2084] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2085] The following table describes characteristics of hybrid phenyl based ionomeric copolymers, which may be subdivided into two classes, namely alkane and aldehydes, describing the functional groups attached to the aromatic ring. Easily functionalized by sulfonic acid, hybrid phenyl copolymers comprise linear copolymers alternating phenyl or phenol groups with either alkane or aldehyde strands.

TABLE-US-00033 ionomer structure endoskeleton solvents, X-L fillers 20. phenyl copolymers hybrid Ph polymers: EPX, PU, solv: EtOH, IPA, ace, sac filler, CNTs, sPh-alkane copolymers PI, PS, PVA, PAm, PAc MIBK, ETAC, TCM, tol oxides, POSS, sPh-aldehyde pillars: reinforcing X-L: Ziegler-Natta NPs, MOFs, PIL fillers (C-fiber, CNTs) catalyst, BF.sub.3, SnCl.sub.4, SbF.sub.3, TiCl.sub.4.

[2086] Endoskeletal polymers able to bond to phenyl aldehydes include epoxy resins (EPX) through covalent bonding between aldehyde groups; polyurethanes (PU) through hydroxyl to polyol bonds; polystyrene (PS, PSt) which is an alkylbenzene able to bond to alkanes; polyacrylates (PAc) made from acrylic acids able to form ester linkages with alcohol groups on a phenyl-alkane chain; polyvinyl (PVA) reacting with aldehyde groups of phenyl-aldehydes to form hemiacetals or acetals; polyimides (PI) synthesized from diamines and diacids able to form amide bonds to amino group or a carboxylic acid group on phenyl-alkane or phenyl-aldehyde chains.

[2087] Solvents of the phenyl group in phenol based polymers include ethanol (EtOH, CH.sub.3CH.sub.2OH); IPA (2-propanol, isopropyl alcohol); acetone (ace, 2-propanone, dimethyl ketone), MIBK (4-methylpentan-2-one, (CH.sub.3).sub.LCHCH.sub.2C(O)CH.sub.3)); ethyl acetate (ETAC, EtOAc, ethyl ethanoate, C.sub.4H.sub.8O.sub.2); chloroform (TCM, trichloromethane, CHCl.sub.3); and toluene (tol, toluol, C.sub.6H.sub.5CH.sub.3, PhCH.sub.3). Polymerization of alkanes can be performed using Ziegler-Natta catalysts prepared by reacting certain transition metal halides with organometallic reagents such as alkyl aluminum, lithium and zinc reagents. Aldehyde polymerization is catalyzed by boron trifluoride (BF.sub.3), tin tetrachloride (SnCl.sub.4), antimony trifluoride (SbF.sub.3), and titanium tetrachloride (TiCl.sub.4). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

21. Functionalized Hybrid Polystyrene (PS, PSt) Copolymer IEMs.

[2088] While section 10 describes pristine polyolefin sulfonated polystyrene membranes, this section describes copolymers of polystyrene (PS, PSt) used to form hybrid IEMs. As described, polystyrene can form copolymers with itself through multi-chain cross linking, linear copolymers with polystyrene sulfonates, grafted polymers with perfluoroalkoxy alkanes, copolymers with polyurethane thermoplastics, and linear mainchains comprising both rigid and flexible polystyrene segments.

[2089] Like many polyolefins, pure polystyrene is not a good electrical conduction, but can be functionalized by sulphonic acid or other acid groups to form ionomers, or functionalized by bonded metallic groups, fillers, or dopants to form catalytic groups. Made in accordance with this invention, both ionomeric and catalytic IEMs of polystyrene can be rendered useful for application of filtering, purification, electrolysis, and membrane fuel cells.

[2090] FIG. 223 depicts two topological variations of functionalized polystyrene. Specifically linear sulfonated poly(trifluorostyrene) (sPTFS) 1619s illustrates a linear fluorocarbon mainchain with sulfonated phenyl groups substituted for fluorine on the backbone. This bonding configuration is reminiscent of PFSA except that fluorocarbon pendants have been replaced by an aromatic ring with an attached sulfonic acid (SO.sub.3H) 1054 group. In this sense, the sPTFS behaves like a short sidechain PFSA ionomer except that the aromatic ring increases film porosity somewhat by disturbing matrix crystallinity, but not as much as glassy matrices involving PFMMD or PDDP linear copolymers. Made in accordance with this invention, the lower porosity caused by the short sidechain can bae compensated by using a sacrificial filler or by doping the film with silica or other permanent filler to disrupt PSt crystallinity.

[2091] Another way to improve gas transport while increasing film strength is achieved through cross linking between or among multiple sPTFS backbones as depicted by cross-linked sulfonated poly(trifluorostyrene) (sPTFS-X) 1619. Although cross linking may involve an organic ligand such as glutaraldehyde, in other instances a shared ionomer may perform the same function through electrostatic cross linking, even if the ionomer is covalently bonded to only one PSt mainchain. For example, sPTFS-X 1619 illustrates poly(trifluorostyrene) 1619p of chain length n is bonded to a second poly(trifluorostyrene) 1619m or chain length m through an acidic cross link 1620x comprising two phenyl groups sharing a common sulfonic acid 1054x.

[2092] FIG. 224 illustrates the molecular structure of a styrene-ethylene blended polymeric ionomer comprising the linear copolymer unit cell 1621 of a polystyrene-co-polystyrene-sulfonate (PS-co-sPSS) copolymer including a carbon-free polystyrene backbone and a polystyrene segment 1621a linearly bound to inserts of polyethylene (PE) 1621b, and polybutylene (PBu) 1621c.

[2093] It should be noted that although nascent ethylene (H.sub.2CCH.sub.2) and butylene (H.sub.2CCHC.sub.2H.sub.x) contain carbon-to-carbon double bonds, in the polymeric forms secondary bonds to the polymer's mainchain eliminates the double bond by usurping the unused extra electron. As shown, polystyrene segment 1621a contains unfunctionalized polystyrene groups PS and sulfonated portions sPSS with sulphonic acid (SO.sub.3H) 1054 attached to the aromatic ring. As such, the hybrid copolymer is referred to as polystyrene-co-polystyrene-sulfonate (PS-co-sPSS). Given the linking role of the polyethylene (PE) 1621b and polybutylene (PBu) 1621c groups, a more complete name for the copolymer is polystyrene-co-polystyrene-sulfonate-co-polyethylene-co-polybutylene (PS-co-sPSS-co-PE-PBu). The fully descriptive moniker, however is not required as the PE and PBu groups do not influence conductivity and have minimal impact of porosity.

[2094] Another approach to manage strength and porosity of polystyrene ionomers is by grafting of sulfonated polystyrene to other polymer mainchains. In FIG. 225, polystyrene sulfonic acid (PSSA) 1625b is grafted onto poly(perfluoroalkoxy alkane) polymer 1625a to form a grafted copolymer poly(tetrafluoroethylene-co-perfluorovinyl ether)-graft-polystyrene sulfonic acid (PFA-g-PSSA) 1625.

[2095] Polystyrene (PSt) ionomers can also form copolymers with polyurethane (PU). As depicted in FIG. 226A illustrates comprises a poly thermoplastic urethane (PTPU) 1626 forming hydrogen bonds to sulfonated divinyl benzene (sDVB) 1625 resulting in a copolymer thermoplastic polyurethane-co-sulfonated-divinyl-benzene (PTPU-co-sDVB). FIG. 226B illustrates bonding of polystyrene sulfonate 1627 to sulfonated divinyl benzene (sDVB) 1625 via a hydrogen bond between the sulfonic acid group of PSS and the double-bonded oxygen of sDVB.

[2096] The resulting copolymer as shown is thermoplastic polyurethane-co-polystyrene sulfonate-co-sulfonated divinyl benzene (PTPU-co-PSS-co-sDVB). The hydrogen bonding of thermoplastic urethane to sulfonated polystyrene divinyl benzene has applications in electrodialysis but using embodiments of this invention can be enhanced for use in fuel cell applications.

[2097] Another benefit of TPU is its ability to control rigidity, whereas soft and hard segments imparts rubber-like and glass-like characteristics to the backbone. While soft segments include polyether or polyurethane ester (PUE) having molecular weights of 1000-3000, the hard TPU segments include complexes of polyurethane diisocyanate with diols. The combination of hard and soft segments influences mechanical film properties affecting permeation rate and selectivity in gas separation, desalination and pervaporation membranes, and gas permeability in ion exchange membranes.

[2098] The topographical impact of blending flexible polyurethane-ester (PUE) 1630 with rigid scaffolding 1631 is depicted schematically in FIG. 227. As shown, the PTU-co-PUE linear copolymer 1630 and 1631 contains DVB ligand 1625 with sulfonated divinyl benzene groups (sDVB) 1625s. A second polymer backbone comprising polystyrene (PSt) 1627p is functionalized by sulfonic acid groups to form polystyrene sulfonate ionomers (PSS) 1627s.

[2099] The PSS ionomers 1627s further form hydrogen bonds 1628 to DVB ligands 16251 thereby facilitating cross linking between the polystyrene (PSt) 1627p mainchain and the PTU-co-PUE linear copolymer 1630 and 1631. The result is a quatre-copolymer comprising thermoplastic polyurethane-co-polyurethane-ester-co-sulfonated divinyl benzene-co-polystyrene-sulfonate or PTPU-co-PUE-co-DVB-co-PSS 1629. The membrane may also be doped with electroconductive polyaniline as a permanent filler. Polyaniline is a conducting polymer and organic semiconductor of the semi-flexible rod polymer family.

[2100] Membrane top view 3000 and membrane side view 3001 in FIG. 228 illustrate a variety of elements of ionomeric copolymer 3002 comprising thermoplastic polyurethane copolymers made in accordance with this invention, including separately or in combination inventive matter comprising: [2101] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2102] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2103] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2104] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2105] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2106] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2107] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2108] where ionomeric polymer 3002 may comprise exemplary molecules such as linear polymer trifluorostyrene (PTFS) 1619p, cross-linked polymer trifluorostyrene (PTFS) strands 1619x, poly(perfluoroalkoxy alkane) grafted onto polystyrene sulfonic acid (PFA-g-PSSA) 1621, polystyrene to polystyrene-sulfonate copolymer (PS-co-sPSS) 1621, poly(thermoplastic-polyurethane-divinylbenzene-co-polystyrene-sulfonate) aka P(TPU-co-DVB-co-PSS) 1627 optionally blended with other homopolymers such as polyurethane-ester P(TPU-co-PUE-DVB-co-PSS), heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2109] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2110] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2111] where ionomeric polymer 3002 may include ionic fillers including polyaniline (not shown) as well as other permanent fillers pf CNTs, oxides, POSS, NPs, MOFs, and PIL; [2112] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2113] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2114] In order to form PSt conductive ionomers, copolymers of polystyrene are beneficial to control conductivity and porosity. Examples include linear and cross linked poly(trifluorostyrene) (PTFS and PTFS-X); poly(perfluoroalkoxy alkane) grafted copolymers with polystyrene sulfonic acid (P(PFA)-g-PSSA), and polystyrene-sulfonate copolymers (PS-co-sPSS). Styrene-urethane copolymers include poly(thermoplastic-polyurethane-divinylbenzene-co-polystyrene-sulfonate) aka P(TPU-co-DVB-co-PSS) optionally blended with other homopolymers such as polyurethane-ester P(TPU-co-PUE-DVB-co-PSS). The following table describes elements of polystyrene copolymers:

TABLE-US-00034 ionomer structure endoskeleton solvents, X-L fillers 21A. styrene copolymers hybrid PSt polymers: PS-PU, solv. PVDF, NH.sub.4I, sac filler, CNTs, linear PTFS copolymers ABS, PC, PE, PP, Na.sub.2SO.sub.4, DMAc, oxides, POSS, cross linked PTFS-X PVC, PET, PMMA BzOH, EtOAc NPs, MOFs, PIL, P(PFA)-g-PSSA pillars; reinforcing X-L: heat, (BzO).sub.2, polyaniline PS-co-sPSS fillers (C-fiber, CNTs) (OHMe)-BnCl 21B. styrene-urethane copolymer PTPU-co-sDVB-co-PSS PTU-co-PTUE-co-sDVB-co- PSS

[2115] Endoskeletal polymers may include polystyrene-polyurethane (PS-PU) blends; acrylonitrile butadiene styrene (ABS) which bonds to polystyrene through solvent welding dissolving both polymers and welding their surfaces together; polycarbonates (PC) bonded to polystyrene using solvent bonding or with special adhesives that bond to both polymers; polyethylene and polyproline (PE, PP) bondable to polystyrene only following surface treatments such as corona, plasma, or flame treatment whereby PSt surface energy is increased, allowing for better adhesion with adhesives or by using specialized bonding agents; polyvinyl chloride (PVC) bonding to PSt using adhesives compatible with both materials or via solvent welding; polyethylene terephthalate (PET) bonded to polystyrene using suitable adhesives; polymethyl methacrylate (PMMA) bonded to polystyrene using solvent bonding similar to ABS; or by thermoplastic elastomers (TPEs) through over-molding.

[2116] Solvents of polystyrene include polyvinyl difluoride (PVDF), ammonium iodide (NH.sub.4I), sodium sulfate (Na.sub.2SO.sub.4), dimethylacetamide (DMAc), benzaldehyde (BzOH), and ethyl acetate (EtOAc). Polymerization of polystyrene is prepared by free radical addition polymerization of styrene in the presence of benzoyl peroxide (BzO).sub.2 as a catalyst. Post polymerization cross linking include p-hydroxymethyl benzyl chloride (OHMe-BnCl). Polyaniline is a conductive filler and dopant compatible with polystyrene. Other membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

22. Functionalized Hybrid Polysulfone (PSU, PSf) Polymer IEMs.

[2117] A superior albeit more expensive alternative to polycarbonate, polysulfone is a high temperature thermoplastic with superior hydrolytic, thermal, and oxidative stability. Containing an aryle-SO.sub.2-aryle subunit, three forms of polysulfone comprise three moietiespolysulfone (PSU, PSf) described in this section, polyethersulfone (PES, PESU, PESf) discussed in sections 13, 15, 33, 37 and polyphenylene sulfone (PPSU).

[2118] FIG. 229 illustrates a polysulfone molecule 1665 (PSU, PSf) comprising four aromatic rings alternatively linked by methylated carbon and by sulfur dioxide. On its own, polysulfone is neither ionomeric or catalytic. Given its preponderance of constituent phenyl groups, PSU can easily be functionalized by sulfur dioxide or sulfuric acid into an ionomer comprising a sulfonic acid group.

[2119] As shown in FIG. 230, functionalizing polysulfone 1665 requires several steps comprising (a) treating with nascent polysulfone with N-butyllithium (N-BuLi) and tetrahydrofuran (THF) to attach lithium to one aromatic ring forming intermediary 1637. Subsequent treatment in SO.sub.2 cooled to 65 C. modifies the attached lithium into sulfone intermediary 1638 with a lithium oxide side-group. In the final step, the lithium oxide is functionalized into sulfonic acid (SO.sub.3H) by treatment in hydrogen peroxide (H.sub.2O.sub.2), hydroxide (OH), and hydronium ions (H.sub.3O+), i.e. water plus H.sup.+.

[2120] The resulting sulfonated polysulfone (sPSU) 1639 as shown contains on average one sulfonic acid group (SO.sub.3H) for every four aromatic rings. The molecule is considered a hybrid polymer or heteropolymer because the repeating segments on the mainchain alternate between a sulfone group and a methylated group. Because the two segments are however formed concurrently, the backbone while a heteropolymer is not classified as a copolymer.

[2121] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 231 illustrate a variety of elements of ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising: [2122] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2123] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2124] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2125] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2126] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2127] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2128] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2129] where ionomeric polymer 3002 is polysulfone (PSU, PSf) 1639 optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2130] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2131] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2132] where ionomeric polymer 3002 may include ionic fillers (not shown)I; [2133] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR.sub.4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte, and finally [2134] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2135] The following table describes the construction of polysulfone heteropolymer hybrid membranes:

TABLE-US-00035 ionomer structure endoskeleton solvents, X-L fillers 22. polysulfone hybrid PSf polymers: PEEK, PEI, solv: NMP, DMAc, sac filler, CNTs, heteropolymers polymers PBI, PAm, PE, PP, DMF, CHCl.sub.3, CdCL.sub.2 oxides, POSS, sPSf-PSf PC, ABS, PU X-L: FeCl.sub.3, SbCl.sub.5, NPs, MOFs, PIL pillars; reinforcing BMP, TPO, TMPTA fillers (C-fiber, CNTs)

[2136] Linear heteropolymers of sulfonated polysulfone (sPSU, sPSf) and un-sulfonated polysulfone (PSU, PSf) represent the cost common instances of hybrid PSf copolymers. Endoskeletal pillar materials compatible with polysulfone membranes include: polyether ether ketone (PEEK) and polyetherimide (PEI) bonded to polysulfone using high-performance adhesives resistant to high temperatures; and polyamide (PAm) bondable to PSf using adhesives such as epoxy resins or polyurethane adhesives pursuant to surface preparation such as roughening.

[2137] Polyethylene (PE) and polypropylene (PP) although difficult to bond may use epoxies or modified acrylic bonding subsequent to surface treatments such as corona and plasma treatments used to increase the surface energy and improve adhesion; polycarbonate (PC) bondable to polycarbonate using adhesives that are compatible with both materials such as certain epoxies or solvent-based adhesives; acrylonitrile butadiene styrene (ABS) bondable to polysulfone using adhesives like cyanoacrylates, epoxies, or solvent-based adhesives after suitable surface preparation; polyurethanes (PU) using adhesives that form strong bonds with both materials, including polyurethane adhesives and some epoxies; and polybenzimidazole (PBI) with suitable adhesives.

[2138] Solvents used in forming polysulfone polymers include N-methylpyrrolidone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), chloroform (CHCl.sub.3), dimethyl sulfoxide (DMSO), or cadmium chloride (CdCL.sub.2). Catalysts and reagents beneficial in polymerizing polysulfone membranes and cross linking them to other polymers include Friedel-Crafts catalysts such as ferric chloride (FeCl.sub.3, iron (III) chloride) or antimony pentachloride (SbCl.sub.5). Cross linking of polysulfone can be performed by 4,4-trimethylene bis(1-methylpiperidine) (BMP) or by photoinduced cross linking in 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (TPO) and trimethylolpropane tri-acrylate (TMPTA). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

23. Functionalized Hybrid Polyamide Sulfonimide (PAm-Co-Sim) Copolymer IEMs.

[2139] Another category of ionomeric polymer is functionalized polyamides. Polyamides are polymers formed of repeating units linked by intervening amide bonds facilitating good thermal and chemical resistance as well as controlled crystallinity. A polymer of amide, not to be confused with polyimide, comprises a general structure a backbone of NCR where the nitrogen form a single H-N bond and the oxygen forms a CO double bond to the on-chain carbon, or more simply as the chemical formula (OC)(NH). Polyamides applicable for membranes comprise a subgroup called aramids or aromatic polyamidesamide polymers that contain phenyl rings in their repeating units. One motivation for forming ionomeric polyamides is the elimination of sulfonic acid groups (SO.sub.3H) found to be subject to degradation by hydrogen peroxide (H.sub.2O.sub.2) present in an IEM matrix.

[2140] An exemplary process for formation of functionalized polyamide is illustrated in FIG. 232, where reactants 1640 and 1641 are combined with sodium hydroxide (NaOH) and water (H.sub.2O) at 95 C. for 8 h resulting in diphenyl sulfonimide monomer 1642 having a chemical structure (Ph-SO.sub.2NHSO.sub.2-Ph) with ionic (NH.sup.+) group 1646. Subsequent treatment in potassium manganate (KMnO.sub.2), lithium hydroxide (LiOH), and water at 95 C. for 8 h converts the phenyl group into benzoic acid 1647 resulting in the monomer 4,4-dicarboxyldiphenyl sulfonimide of the form (BzOH-SO.sub.2NHSO.sub.2BzOH) abbreviated as Slm 1643.

[2141] FIG. 233A illustrates a reaction of Slm 1643 with sulfonated polyamide (SPA) 1644 in the presence of N-methylpyrrolidone (NMP), triphenyl phosphate (TPP), pyridine (C.sub.5H.sub.5N), and calcium chloride (CaCl.sub.2) at 100 C. for 8 h resulting in the copolymer polyamide sulfonimide (SPA-co-Slm) 1645 with ionic (NH.sup.+) group 1646 as an ionomer. In an alternative ionomeric polymer shown in FIG. 233B, reactant 4,4-dicarboxyldiphenyl sulfonimide monomer Slm 1643 is combined with sulfonated polyamide (sSPA) 1644s resulting in sulfonated copolymer sSPA-co-Sim 1645s including ionomer-A with ionic (NH.sup.+) group 1646 and ionomer-B comprising sulfonic acid 1054. This new ionomeric polymer offers higher conductivity than its purely polyamide antecedent. It is also the first known reported polymer containing two different ionomer typesionomer-A comprising a hydrogen ion based ionic (NH.sup.+) group 1646, and ionomer-B comprising a sulfonic acid group (SO.sub.3H) 1054. By integrating two different redundant ionomer types into one ion exchange membrane, the risk of degraded membrane conductivity from membrane poisoning is reduced.

[2142] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 234 illustrate a variety of elements of ionomeric polymer 3002 comprising a polyamide sulfonimide IEM made in accordance with this invention, including separately or in combination inventive matter comprising [2143] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2144] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2145] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2146] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2147] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2148] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2149] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2150] where ionomeric polymer 3002 is polyamide sulfonimide 1645 optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2151] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2152] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group N.sup.H.sup.+, SO.sub.3H, SO.sub.3Na, and sulfobutyl groups, and a second ionomer comprising sulfonic acid SO.sub.3H, integrating two different ionomers into a common IEM. [2153] where ionomeric polymer 3002 may include ionic fillers (not shown); [2154] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally, [2155] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2156] The following table describes the construction of polyamide-sulfonimide copolymer hybrid membranes. Linear copolymers of sulfonated and un-sulfonated polyamide (PAm) represent the principal instance of hybrid PAm copolymers. Endoskeletal pillar materials compatible with polyamide membranes include cyanoacrylate adhesives (CA) able to bond to fine features especially when fast curing is desirable; epoxy adhesives (EPX) bond to PAm, especially two-component epoxies offering improved durability; polyurethane (PU) form strong flexible bonds with PU using polyurethane adhesives or solvent welding.

TABLE-US-00036 ionomer structure endoskeleton solvents, X-L fillers 23. polyamide sulfonimide hybrid PAm polymers: CA, PU, solv: HF, PFD, sac filler, CNTs, copolymers copolymers EPX BTF, F-626 oxides, POSS, SPA-co-Slm pillars: reinforcing X-L: CPL, SAm NPs, MOFs, PIL fillers (C-fiber, CNTs)

[2157] Solvents used in forming polyamide-sulfonimide polymers include formic acid (FA), cresol (C.sub.7H.sub.8O), or fluoric solvents such as fluorane (HF), perfluorodecalin (PFD), benzotrifluoride (BTF), and perfluorooctyl-dimethylbutyl-ether (F-626). Catalysts and reagents beneficial in polymerizing polyamide-sulfonimide membranes and cross linking them to other polymers include E-caprolactam (CPL, (CH.sub.2).sub.5CNH), sulfonamide (SAm). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

24. Functionalized Hybrid Phosphazene (Pz) Polymer IEMs.

[2158] Phosphazene comprises several classes of organophosphorus compounds comprising phosphorus (V) with a double-bond between phosphorus and nitrogen, i.e. N=P. Although phosphazene, also known as iminophosphoranes or phosphine imides may be used in filter membranes for water purification and gas separation, it can also be functionalized into an ionomeric membrane either for proton exchange membranes including direct methanol fuel cells or in anion exchange membranes. Material properties include resilience to chemical attack, thermal stability, and flexibility.

[2159] An exemplary process for formation of a phosphazene membrane is illustrated in FIG. 235A. In classical phosphazene synthesis, ring opening of hexachlorocyclotriphosphazene (NPCL.sub.2).sub.3 1650 performed by heating at 250 C. for several hours results in the phosphazene monomer dichloro-phosphazene (Cl.sub.2-Pz) 1651. The phosphazene monomer can be polymerized into poly(phosphazene) (PPz) 1652 by heating at temperatures exceeding 250 C. Alternatively, the reaction can be catalyzed by Lewis acids such anhydrous aluminum chloride (AlCl.sub.3) at 200 C. or by trichlorobenzene (TCB) with hydrated calcium sulfate (CaSO.sub.4.Math.2H.sub.2O) as a promoter and sulfamic acid (HSO.sub.3 (NH.sub.2)) as a catalyst. During polymerization, the chloride groups of the Cl.sub.2-Pz 1641 precursor are replaced by radical R, specifically where R comprises a phenyl group attached to oxygen, aka phenol ether or Ph-OH.

[2160] Subsequent oxidation in concentrated sulfuric acid (H.sub.2SO.sub.4) sulfonates the phenol groups thereby synthesizing poly sulfonated phosphazene P(sPz) 1653s. Not all phosphazene groups become sulfonated. Some radical remain as unfunctionalized phenol groups. A linear copolymer comprising a mix or sulfonated phosphazene P(sPz) 1653s and un-sulfonated phosphazene P(Pz) 1653 is illustrated in FIG. 235B as poly(sulfonated phosphazene-co-phosphazene), symbolically as P(sPz-co-Pz).

[2161] Membrane top view 3000 and membrane side view 3001 in FIG. 236 illustrate a variety of elements of ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising: [2162] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2163] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2164] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2165] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2166] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2167] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2168] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2169] where ionomeric polymer 3002 is sulfonated and un-sulfonated phosphazene 1653s and 1653 optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2170] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2171] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2172] where ionomeric polymer 3002 may include ionic fillers (not shown)I; [2173] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2174] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2175] Linear copolymers of sulfonated and un-sulfonated phosphazene (Pz) represent the principal instance of hybrid PAm copolymers. Endoskeletal pillar materials compatible with phosphazene (Pz) membranes include: compatible phosphazene blends (Pz) formed to achieve specific chemical and structural properties present in the Pz membrane; polyurethanes (PU) using polyurethane adhesives offering versatile adhesion capabilities; silicone polymer (SiP) bonded to Pz using silicone-base polymer adhesives; and epoxy resins (EPX) offering strong adhesive properties bonding with a variety of materials including Pz. The table below describes the construction of phosphazene copolymer hybrid membranes:

TABLE-US-00037 ionomer structure endoskeleton solvents, X-L fillers 24. phosphazene hybrid Pz polymers: Pz, PU, SiP, EPX solv: C.sub.6H.sub.14, tol, sac filler, CNTs, heteropolymer polymers pillars: reinforcing fillers THF oxides, POSS, P(sPz-Pz) (C-fiber, CNTs) X-L: AlCl.sub.3, TCB, NPs, MOFs, PIL CaSO.sub.4, HSO.sub.3(NH.sub.2)

[2176] Solvents of phosphazene (Pz) include tetrahydrofuran (THF, oxolane), hexane (C.sub.6H.sub.14), and toluene (tol, PhCH.sub.3). Catalysts and reagents beneficial in polymerizing phosphazene (Pz) membranes and cross linking them to other polymers include Lewis acids such anhydrous aluminum chloride (AlCl.sub.3) or trichlorobenzene (TCB), hydrous calcium sulfate (CaSO.sub.4.Math.2H.sub.2O), and sulfamic acid (HSO.sub.3 (NH.sub.2)). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here. Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

25. Hybrid Siloxane (SiX) Polymer IEMs.

[2177] Siloxanes are polymers comprising a backbone of silicon and oxygen [-SiOSiOSi-] forming strong bonds resilient to attack. These silicon sites also bond to organic radical side groups R.sub.1, R.sub.2, and R.sub.3 producing a polymer [-R.sub.2SiOSiR.sub.2OSiR.sub.3-]. Each silica functional group [R.sub.xSiO], referred to siloxy, may be identical or may differ from one another.

[2178] These radicals, often comprising methyl, ethyl or phenyl groups define many of the polymer's material properties such as crystallinity, porosity, rigidity, durability, and temperature coefficient. Siloxane also known as silicone should not be confused with the element silicon which it containssilicon is an element, silicone is a polymer. As, such siloxane can be used in forming membranes for a variety of application including high selectivity separation of gasses and liquids, for proton and anion ion exchange membranes in fuel cells, for separators in lithium ion batteries, for hydrolysis, for electrodialysis, for antibacterial filtering, and more.

[2179] While pristine siloxane containing few ionized groups exhibits poor electrical conductance, any or all of these side groups can then be functionalized by catalytic or ionomeric termini. An exemplary heteropolymer for siloxane membrane is illustrated in FIG. 237 comprising un-functionalized poly siloxane P(SiX) 1655 and sulfonated poly siloxane P(SiX) 1655s including sulphonic acid ionomer 1054. Alternatively, phosphonium ionomers can be grafted onto siloxane polymers.

[2180] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 238 illustrate a variety of elements of ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising: [2181] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2182] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2183] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2184] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2185] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2186] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2187] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2188] where ionomeric polymer 3002 is a heteropolymer of sulfonated siloxane 1655s and unfunctionalized siloxane 1655 optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2189] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2190] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2191] where ionomeric polymer 3002 may include ionic fillers (not shown)I; [2192] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR.sub.4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2193] Endoskeletal pillar materials compatible with phosphazene (Pz) membranes include: compatible phosphazene blends (Pz) formed to achieve specific chemical and structural properties present in the Pz membrane; polyurethanes (PU) using polyurethane adhesives offering versatile adhesion capabilities; silicone polymer (SiP) bonded to Pz using silicone-base polymer adhesives; and epoxy resins (EPX) offering strong adhesive properties bonding with a variety of materials including Pz; [2194] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2195] The table below describes the construction of siloxane heteropolymer hybrid membranes:

TABLE-US-00038 ionomer structure endoskeleton solvents, X-L fillers 25. siloxane hybrid SiX polymers: SiA, PU, solv: C.sub.7H.sub.16, tol, sac filler, CNTs, heteropolymers polymers EPX, CA Bz, TCM oxides, POSS, P(sSiX-co-SiX) pillars: reinforcing X-L: C.sub.2Bz, Me.sub.2 NPs, MOFs, PIL fillers (C-fiber, CNTs)

[2196] Endoskeletal pillars bonding with siloxane membranes include silicone-based adhesives (SiA) and polyurethanes (PU) both well matched to bonding silicone membranes; and for epoxy resins (EPX) and cyanoacrylate adhesives (CA) as a general purpose adhesives. Solvents for siloxane (SiX) copolymers include heptane (C.sub.7H.sub.16), toluene (tol), benzene (Bz), and chloroform (trichloromethane, TCM). Catalysts and reagents beneficial in polymerizing siloxane (SiX) hybrid membranes include dichlorobenzoyl catalysts such as 2,4-dichlorobenzoyl peroxide (C.sub.14HCl.sub.4O.sub.4), and dimethyl compounds such as 2,5-dimethyl (C.sub.32H.sub.66O.sub.2). Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

26. Functionalized Hybrid Triazine (Tz) Polymer IEMs.

[2197] Triazine is a class of nitrogen-containing heterocycles based on the general molecular formula is C.sub.3H.sub.3N.sub.3. Comprising a six-sided benzene-like ring with three nitrogen for carbon substitutions, triazine molecules are named by the location of the nitrogen substitutions on the aromatic ring, e.g. 1,2,4-triazine substitutes nitrogen on the first, second, and fourth positions. For the purpose of this invention, there is no distinction among these variation topological moieties as they only secondarily influence ionomeric membrane performance by influencing crystallinity. FIG. 239 comparatively illustrates an overview of triazine monomers from reference Wikipedia showing three molecular configurations 1660 and two exemplary common moieties melamine 1661 and triazine 1662 not specifically related to IEMs.

[2198] FIG. 240 illustrates an exemplary process for formation of a perfluorinated covalent triazine framework reacting benzaldehyde 1670 with ammonium iodide (NH.sub.4I) and H.sub.2O to form intermediary 1671. By ionization of I.sub.2 into I.sup. and oxidation of Fe.sup.2+ to Fe.sup.3+ forming triazene template 1673, addition reaction connects additional phenyl groups sequentially 1674 centered around a locus forming a covalent triazine framework (CTF) 1675 with three phenyl groups and a triazine (C.sub.3H.sub.3N.sub.3) core 1679. The CTF becomes the building block for vastly more complex and expansive triazine structures. For example, treatment in a sulfonic acid like OHE functionalizes CTF 1675 into sulfonated covalent triazine polymer 1676 with sulfonic acid ionomer 1054. Alternatively for use in direct methanol fuel cells, covalent triazine frameworks can be functionalized by phosphoric acid (H.sub.3PO.sub.4). Synthesis of triazine frameworks include low-temperature synthesis and subsequent steps for sulfonating triazine's aromatic rings. Pd nanoparticles can be included to form a bifunctional catalyst for one pot hydrogenation esterification reactions.

[2199] FIG. 241 illustrates how ammonium iodide (NH.sub.4I) 1680 can be polymerized into various triazine configurations of covalent triazine frameworks (CTFs). For example, sulfonated 1,4-benzoquinone 1681 commonly known as para-quinone (C.sub.6H.sub.4O.sub.2) forms a circular-shaped CTF 1684a of twelve aromatic rings in the CTF, half of which are comprise triazine groups, the other half forming sulfonated phenyl groups. Unique to this application we define a the first ever nomenclature for covalent triazine frameworks where accordingly CTF 1684a is be called 6T6sPh sCTF-12.

[2200] The term sCTF-12 is a top level descriptor describing covalent triazine frameworks (CTF) 1684a comprises 12 aromatic rings (12) lining its interior surface and is sulfonated at least in part, hence the prefix of a small letter s. This name does not describe how many phenyls or triazine radiate outside the inner ring of the CTF. The nominative 6T6sPh provides a greater structural detail when 6T refers to six triazine rings 1679 while the term 6sPh means the CTF also includes six sulfonated phenyl rings. The two description can be used separately or preferably together to describe the superstructure of a covalent triazine framework. Mixing ammonium iodide (NH.sub.4I) 1680 with three benzene compound 1682 results in a different CTF framework 1684b. While this CTF has a more tile-like geometry than the first example. As shown it contains only nine aromatic rings on its inner periphery, hence its name sCTF-9. That said the CTF unit cell comprises a total of three triazines 1679 and twelve sulfonated phenyl groups. As such, its superstructure is 3T12sPh. In other words the CTF unit cell is composed of 15 rings, only nine of which reside on its inner periphery. If ammonium iodide (NH.sub.4I) 1680 is mixed with tetrafluoro-1,4-benzoquinone 1683 the resulting triazine framework CTF-12 is also circular shaped with twelve aromatic rings, none of them sulfonated hence its name CTF-12. The term 6T6Ph-F.sub.4 identifies the framework includes six triazines 1619, and six phenyls each with four fluorine atoms.

[2201] Although covalent triazine frameworks may manifest tile-like or ring-like geometries, some structures are topologically more linear or random. FIG. 242 illustrates several examples of phosphorylated covalent triazine frameworks, i.e. pCTFs. In each instance shown, a phosphoric acid group (H.sub.3PO.sub.4) 1677 has been attached to one or more triazine groups as a source of protons for conduction. Other phosphoric acid groups may also attach to available nitrogen or fluorine atoms. A phosphoric doped covalent triazine framework is therefore designated by its acronym pCTF.

[2202] For example in phosphorylated CTFtetrafluoride (pCTF-TF) 1687, two triazines 1679 bind a center tetrafluoride phenyl group. Phosphoric acid groups 1677 bond to nitrogen atoms of the triazine but also bond to fluorine atoms on the tetrafluoride group. No fluorine is present in this example, meaning ionomeric conduction is regulated by the phosphoric groups and not be sulfonic acid as in most ionomers.

[2203] By contrast, phosphorylated CTFsulfonated phenyl (pCTF-sPh) 1685 made in accordance with this invention combines both phosphoric acid 1677 and sulfonic acid 1054 into a common covalent triazine framework representing a new class of ionomer, described herein as a co-ionomer able to conduct through two different ionomeric moieties in the same group. Advantages of the newly invented co-ionomer is its ability to conduct over a wider range of ambient conditions such as hydration, pH, and temperature and to provide redundancy protecting against ionomer poisoning by H.sub.2O.sub.2 and other parasitic compounds. As shown pCTF-sPh 1685 includes phosphoric acid 1677 bonded to nitrogen atoms of triazine 1679 and sulfonic acid 1054 bonded to the phenyl group Ph held between the two triazine groups. As such, the moniker pCTF-sPh describes a phosphorylated covalent triazine framework with a sulfonated phenyl group.

[2204] Another example of phosphoric-sulfonic co-ionomer CTF is the molecule shown in the center illustration comprising phosphorylated CTFsulfonated tris(4-formylphenyl)amine aka pCTF-sTPA 1686. As its name indicates, the triazine framework comprises one phosphorylated triazine group 1679 with attached phosphoric acid 1677 molecules (pCTF) combines with sulfonated tris(4-formylphenyl)amine comprising a central nitrogen axle and three phenyl groups, each with attached sulfonic acid (SO.sub.3H) 1054 groups, hence its name sTPA as the acronym sulfonated tris-phenylamine. As shown, the central nitrogen may also bond to an additional phosphoric acid group.

[2205] FIG. 243A illustrates a sulfonated covalent triazine framework sCTF-24 1692 comprising (a) 6 triazine groups, (b) 12 phenyl groups, and (c) 6 reflected bi-pyrrole groups. In accordance with this invention the molecule can be identified as 6T12sPh6bPy meaning six triazine (CT), twelve sulfonated phenyls (12sPh), and six reflected bi-pyrrole groups (6bPy) forming the sCTF-24 covalent triazine framework with a 24 element inner periphery. Although the original application of this triazine network is for filtration, in accordance with this invention the phenyl groups have been functionalized by sulfonic acid (SO.sub.3H) 1054 to convert the un-sulfonated CTF into an ionomer sCTF.

[2206] FIG. 243B illustrates an exemplary process for formation of a blended PVDF-triazine polymer forming a porous functionalized covalent-triazine frameworks for enhanced adsorption toward polysulfides in Li-S batteries and organic dyes. The described CTF copolymer is intended as a separator for lithium ion batteries and is therefore not ionomeric or designed to conduct protons. As such, it is not useful in ionomeric or catalytic membranes needed in fuel cells, electrolysis systems, or in electrodialysis, but is insightful in designing triazine fabrication sequences.

[2207] Made in accordance with this invention, the CTF has been sulfonated into sCTF 1692 by the addition of sulfonic acid (SA, SO.sub.3H) 1054 onto the phenyl groups in the CTF superstructure as combined with triazine 1679. This step can be performed by modifying phenyl groups using an aromatic substitution reaction, wherein a hydrogen atom on an arene is replaced by a sulfonic acid group (SO.sub.2OH) in an electrophilic aromatic substitution reaction with fuming sulfuric acid (H.sub.2SO.sub.4) where

##STR00008##

[2208] As indicated sulfur trioxide (SO.sub.3) or its protonated derivative is the electrophile substituted for hydrogen in the reaction. Since water is a byproduct of the reaction, dehydrating agents can accelerate reaction rates by reducing acid dilution during the reaction. For example, adding thyionl chloride (SOCl.sub.2) to the above reaction eliminates the production of excess water by instead forming (SO.sub.2+2HCl). An alternative to sulfuric acid is to sulphonate the aromatic ring using chlorosulfuric acid (HSO.sub.3Cl) in which case the substitution react becomes

##STR00009##

[2209] Other methods to sulphonate benzene or phenyl rings include the Tyrer sulfonation process developed in 1917 and the Piria reaction of 1851. Regardless of the method used to sulphonate the phenyl groups of the triazine framework, he resulting molecular structure 1693, once modified is suitable for use in membranes. Rather than attempting to form a whole new class of membranes and overcome all the challenges therein, an alternative is blend the sulfonated CTF as a filler and dopant into an existing membrane fabrication process. One such candidate is polyvinylidene fluoride (PVDF). As shown polyvinylidene fluoride (PVDF) 1690 with a molecular structure (C.sub.2H.sub.2F.sub.2).sub.n 1691 when combined with the newly reported sulfonated covalent triazine framework sCTF 1682 can produce a sulfonated version of a copolymer of PVDF and CTF, i.e. sulfonated covalent triazine framework polyvinylidene fluoride copolymer (sCTF-co-PVDF). Since the ionomeric regions added to the CTF having the same morphology as the un-sulfonated copolymer pictured in SEM 1694.

[2210] Because covalent triazine frameworks were developed for antibacterial filters and for water purification, they are not ionomeric nor catalytic nor do they represent the same field of science or inventive art as ion exchange membranes. As described above, using methods made in accordance with this invention to functionalize covalent triazine frameworks (CTFs) into sulfonated covalent triazine frameworks (sCTFs), phosphorylated covalent triazine frameworks (pCTFs), or the combination of both into co-ionomeric sulfonated phosphorylated covalent triazine frameworks (spCTF).

[2211] FIG. 243C illustrates a sulfonated version of a 6T18sPh covalent triazine framework (sCTF-24-Pt) 1688 comprising 6 triazine (C.sub.3H.sub.3N.sub.3) 1679 groups and 16 phenyl groups functionalized by sulfonic acid (HSO.sub.3) ionomer 1689. Uniquely, the sCTF-24 shown includes a platinum (Pt) ion 1695 at its center. Alternatively, this metallic core could have been palladium (Pd) or any other catalyst. As shown hydrogen gas 1696 passing through the triazine pore unavoidably encountering the catalyst 1695 splitting the fuel into protonic hydrogen ions (H.sup.+) and electrons 1697. Given the close proximity between the catalyst and ionomer the charge transfer efficiency is enhanced as cations formed by the catalyst are instantly handed off to the ionomers 1689 for charge hopping conduction. This efficient charge transfer mechanism between catalyst and ionomer means that this inventive hybrid catalyst-ionomer covalent triazine framework (sCTF-24-Pt) 1688, offering improved conductance, particularly if the sCTF is coated atop an ion exchange membrane as an interfacial layer between the membrane and catalyst.

[2212] Alternatively a scavenger metal such as nickel, iron, cobalt, etc. could be inserted in place of catalyst metal 1695, the purpose of which is to bond to or impede the transport of carbon monoxide through the membrane especially to protect the anode catalyst from carbon monoxide poisoning. As a protective layer, sCTF-24-Pt 1688 should be coated on the cathode side of the membrane to disrupt CO diffusion before it can even enter the IEM. The protective function of scavenger metals is described in greater detail in section 34 on MOFs.

[2213] Although aforementioned processes involve co-synthesis of covalent triazine frameworks functionalized by sulfonic or phosphoric acid, an alternative process of doping a triazine substrate after it is fabricated is shown in FIG. 244. As depicted triazine substrate 1702 comprises a hexagonal tile with pores 1703 having dimensions of 1.7 nm. Comparing the pore size with the molecular dimensions of the substituted acids 1700 reveals that sulfonic acid with dimension 1701s of 0.16 nm is smaller than that of phosphoric acid 1701p having dimensions 0.37 nm, more than double that of sulfonic acid. As such, made in accordance with this invention, functionalizing a triazine membrane with sulfonic acid 1701s producing a higher acid load in substrate 1702 and therefore offers a greater enhancement in conductivity than its phosphoric counterpart.

[2214] Another fabrication method for forming an ionomeric membrane with triazine does not involve covalent triazine networks but instead comprises triazine containing bisphenols (TBPh) formed by bonding sulfonated bisphenols to triazine 1679. As shown in FIG. 245, the triazine containing bisphenol (TBPh) compound forms a copolymer with bis(4-phenylsulfone) (BPhSf), together forming a sulphonated poly(arylene ether sulfone) triazine bisphenol linear copolymer P(SPAESf-co-TBPh) 1704.

[2215] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 246 illustrate a variety of elements of ionomeric polymer 3002 made in accordance with this invention, including separately or in combination inventive matter comprising: [2216] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2217] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2218] where the pillars comprise a reinforced core 3007 containing carbon fiber, CNTs or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2219] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2220] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2221] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2222] where an optional nanocoating 300 is formed atop membrane 3003 or at the interface between the cathode catalyst and the membrane to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning, and where the nanocoating may comprise a covalent triazine framework containing ionomers and/or catalysts such as Pt or Pd, and/or scavenger metals such as Ni, Co, or Fe, and/or may include boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2223] where ionomeric polymer 3002 is sulfonated triazine 1710, phosphorylated triazine 1702, or uniquely both sulfonated and phosphorylated triazine, optionally blended with other homopolymers, heteropolymers, and copolymers, such as SPAESf or PVDF thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2224] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2225] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2226] where ionomeric polymer 3002 may include ionic fillers (not shown)I; [2227] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte and finally; [2228] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2229] The table below describes the construction of triazine (Tz) polymer and copolymer hybrid membranes:

TABLE-US-00039 ionomer structure endoskeleton solvents, X-L fillers 26. triazine copolymers hybrid Tz triazine polymers: solv: DMSO, EtOH, triazine fillers/coat: and heteropolymers polymers & EPX, Ph, PI, CE MeCN, MeOH, 6T6sPh, 3T12sPh, PCTF/sCTF copolymers copolymers: pillar H.sub.2O, TCM 6T6Ph-F.sub.4, pCTF-sPh, PCTF-sPh matched to IEM X-L: SA, HCl, KOH, PCTF-TF, sCTF-24, PCTF-sTPA polymer; NaOH, AlCl.sub.3, ZnCl.sub.2, PCTF-sTPhA, PCTF-TF pillars: reinforcing heat, UV light 6T18sPh-Pt 6TsPh, 3T6sPh fillers (C-fiber, CNTs) membrane fillers: 6T6Ph-F.sub.4 sac filler, CNTs, 6T12sPh6BPy oxides, POSS, NPs, sCTF-co-PVDF MOFs, PIL P(SPAES)-co-TBPh

[2230] Ionomers include sulfonated and phosphorylated covalent triazine frameworks (CTF) where a lowercase p prefix indicates phosphorylated CTFs, a lowercase s prefix indicates a sulfonated CTF, phenyl, or phenol group, and a upper case P denotes a polymer. Endoskeletal pillars able to bond to triazine membranes include epoxy resins (EPX) creating a cross-linked network between the epoxy matrix and the triazine framework; phenolic resins (Ph) linking the CTF via phenol ligands; polyimides (PI) which easily bond to triazine as PI often triazine rings in their structure to provide high thermal stability and enhance its mechanical strength; and cyanate esters (CE) which easily polymerize through and into triazine rings, forming a highly cross-linked thermoset polymer with excellent thermal stability and dielectric properties.

[2231] Solvents used in forming triazine (Tz) polymers include dimethyl sulfoxide (DMSO) comprising a highly polar organic solvent that can dissolve many organic and inorganic compounds including some triazines; acetonitrile (MeCN) a polar aprotic solvent able to dissolve a wide range of compounds including triazines; methanol (MeOH) and ethanol (EtOH), polar solvents that can dissolve many polar substances including some triazines; water (H.sub.2O) able to dissolve water soluble triazines especially those with hydrophilic groups; and chloroform (trichloromethane, TCM), another slightly polar solvent.

[2232] Catalysts and reagents beneficial in polymerizing siloxane-triazine (Tz-Sx) hybrid membranes and cross linking them to other polymers include strong acids such as sulfuric acid (H.sub.2SO.sub.4, SA) or hydrochloric acid (HCl); strong bases such as sodium hydroxide (NaOH) or potassium hydroxide (KOH); Lewis acids comprising metal salts such as aluminum chloride (AlC.sub.3) or zinc chloride (ZnCl.sub.2); heat and ultraviolet light. Triazine nanoparticles can also be used as fillers or coatings including the previously described molecules and frameworks 6T6sPh, 3T12sPh, 6T6Ph-F4, pCTF-sPh, pCTF-TF, sCTF-24, pCTF-sTPhA, and 6T18sPh-Pt. Other membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

27. Functionalized Poly Methyl Methacrylate (PMMA) Hybrid Polymer IEMs.

[2233] Methyl methacrylate (MMA) with the chemical composition CH.sub.2C(CH.sub.3)COOCH.sub.3. is a methyl ester of methacrylic acid (MAA). MMA is the monomer of poly methyl methacrylate (PMMA) used primarily in the production of acrylic plastics, one of the oldest plastic in use. It is also used as a economical alternative to alternative to polycarbonate (PC) when flexural and tensile strength, transparency, and UV tolerance are more important than impact strength, chemical resistance, and heat resistance. Compared to polystyrene and polyethylene, PMMA is more stable to environmental insults. Non electrochemical applications of PMMA include lenses for vehicular lighting and eye glasses, signs and displays, window coatings, and as a shatter proof substitute for glass. It is also used extensively for medical and dental fillers and implants including the hollow fiber kidney.

[2234] Applications of PMMA membranes have been primarily for kidney dialysis. Because of its small pore size, PMMA is also used for air separation. Conversely, the small pore size of pristine PMMA makes a poor candidate for ion exchange membranes limiting gas and ionic transport thereby diminishing conductance. Attempts to form ionomeric membranes with PMMA rely on copolymerization to enhance film porosity. For example FIG. 247A illustrates steps for forming a MMA copolymer starting with the methyl methacrylate (MMA) monomer 1705 combined with a sulfonated co-monomer 1-(4-sulfobutyl)-3-vinylimidazolium (SA-BVIm) 1706 and with trifluoro-methanesulfonate (MeTfO) 1707.

[2235] Using photochemical cross-linking to promote the reaction the copolymer sulfobutyl-vinylimidazolium trifluoro methanesulfonate-co-methyl methacrylate (sBVlm-TfO-co-MMA) 1708. The impinging light source comprises photons with energy E=h where =h/c is the frequency of the light used in photoexcitation, h is Planck's constant, and c is the speed of light.

[2236] This process comprises photoactivation od protic ionic liquid [HSO.sub.3BVIm][TfO] with MMA and hPFSVE to form aromatic rings with sulfonic acid (SO.sub.3H) mediated via cyclopropene radicals (C.sub.3H.sub.3). Photo processing is however not scalable to production volumes and suffers from poor uniformity and incomplete polymerization.

[2237] An alternative approach shown in FIG. 247B is to employ vinyl addition polymerization to convert methyl methacrylate (MMA) monomer 1705 to poly methyl methacrylate (PMMA) 1712. The methyl group (CH.sub.3) formed by this process is however not ionomeric and not easily functionalized. In accordance with this invention, sulfonation of CH.sub.3 requires a complex sequence involving (i) halogenation, (ii) sulfonic synthesis, (iii) substitution, and (iv) hydrolysis. During halogenation one hydrogen atom in the methyl group is replaced with a halogen such as chlorine or bromine using reagents like chlorine (Cl.sub.2) or bromine (Br.sub.2) in the presence of a catalyst like iron (Fe) or iron (III) chloride (FeCl.sub.3). The result is a benzyl halide, e.g., benzyl chloride if chlorine is used.

[2238] The next step involves introducing the SO.sub.3H group onto the halogenated group. This may be achieved through a sulfonation reaction using fuming sulfuric acid (H.sub.2SO.sub.4) or chlorosulfonic acid (SO.sub.3Cl). During substitution, halogen on benzyl halide can then undergo a nucleophilic aromatic substitution if it is an activated aryl halide, or a nucleophilic aliphatic substitution if it is a primary halide. Should the sulfonation step results in a sulfonyl chloride (RSO.sub.2Cl) instead of a sulfonic acid (SO.sub.3H), a hydrolysis step may be required to convert the sulfonyl chloride into the corresponding sulfonic acid by treatment by water or an aqueous base.

[2239] In the absence of this complex functionalization, the synthesized PMMA 1712 polymer is neither ionomeric or catalytic. Aside than MMA monomer 1705, other monomers shown in FIG. 248 include methacrylate (MA) 1713, methacrylic acid (MAA) 1714, butyl methacrylate (BMA) 1716, and hydroxyethyl methacrylate (HEMA) 1717. These monomers too do not produce ionomeric or catalytic polymers.

[2240] PMMA can also be used to form nanospheres rather than membranes. PMMA nanospheres, properly functionalized and used as permanent fillers in polymers, offer numerous advantage over PMMA membranes. Most notably nanospheres exhibit significantly more surface area and ionomers densities than a two-dimensional membrane comprising sheets of ionomers. This surface area advantage confers greater ionomer density than that available limited to the porous channels and more conduits meandering through a polymeric membrane. These nanoparticles can be used as dopants or fillers in a range of polymers, either to enhance conductivity, control porosity, or catalytically promote faster reaction rates.

[2241] Unfortunately published processes for forming PMMA nanospheres focus on synthesizing nano-coatings for improving light emitting diode efficiency, totally unrelated to forming ionomers for ion exchange membranes. For example, forming PMMA using emulsion polymerization has been researched by the Univ of Wisconsin Madison and published online by its MRSEC group. Focused wholly on polymethylmethacrylate (PMMA) nanospheres for photonics, the fabricated nanospheres enhance optical quantum efficiency but are not intended to enhance fuel cell efficiency.

[2242] The work does however illustrate methods to form PMMA nanospheres. As shown in FIG. 249, the process involves treating a methyl methacrylate monomer 1705 with thermal derivative 1721 of methyl methacrylate 2,2-azobis (2-methyl-propionamidine) (MMA-NH.sub.2) 1720. The chemical product, poly(methyl methacrylate) nanosphere PMMA-NS 1723 itself comprises a linear polymer with methane side groups, some of which populate the surface of the nanosphere. In other words the nanosphere is self forming. The nanospheres are not however ionomeric or catalytic. In other words additional technology is required to functionalize PMMA nanospheres fabricated in this manner. Like triazine described previously, PMMA nanospheres can be formed to host catalytic elements such as palladium. One exemplary process for forming catalytic PMMA forming poly(methyl methacrylate)-supported Pd.sup.0 obtained from room-temperature, dark reduction of ionic aggregates of the unstable Pd.sup.2+ solution ionomer. In this process, methyl methacrylatemethacrylic acid (MMA-MAA) is blended with palladium(II) acetate (Pd(OAc).sub.2, Pd(CH.sub.3COO).sub.2) 1726 along with solvents methanol and benzene at room temperature in the dark to form Pd-poly(methyl methacrylate) nanospheres 1727 and byproduct acetic acid (AcOH, CH.sub.3COOH) 1728 as shown in FIG. 250. The nanospheres 1727 then group into nanoclusters 1729.

[2243] Depending on bridging within the cluster different configurations and reactivities may result as shown in FIG. 251. For example MMA-MAA chain 1734 with covalently bonded symmetrically (COO) bridged palladium 1735 forms nanocluster 1730. By contrast, palladium centric nanocluster 1731 surrounds only a single palladium atom 1735. Asymmetrical PdCOO.sup. bridging produces palladium clusters 1732 while noncoordinating bridging 4[Pd(OCOH)] results in an single Pd anthropomorphic configuration 1733.

[2244] FIG. 252 illustrates how methanol (CH.sub.3OH, MeOH)I is able to convert methyl methacrylate-methacrylic acid (MMA-MAA) 1734 into nanocluster 1736 containing numerous palladium atoms 1735 forming a central locus within the circumscribing MMA-MAA chain 1734. Such PMMA structures, while catalytic are not ionomeric.

[2245] Once a stable nanosphere or nanocluster is formed, functionalization with sulfonic or phosphoric acid is more straightforward. For example, as shown in FIG. 253, the combination of ammonium persulfate (APS) 1741 and copolymer methyl methacrylate (MMA) 1740 produces PMMA unfunctionalized nanosphere 1742. Treatment in KOH swells the polymer while attaching hydroxide (OH) to exposed bonds to produce a reactive PMMA-NS 1743. Subsequent treatment in (3-aminopropyl)triethoxysilane (APTES) attaches silicon to certain surface hydroxide (OH) groups, where each silicon includes dangling NH.sub.2 termini results in amino PMMA 1744. Finally treatment in sulfonated calixarene, i.e. cyclic methylene-linked phenols, results in sulfonated poly(methyl methacrylate (sPMMA) 1745. Conventional applications of PMMA nanospheres include filtration such as removal of vanadium Ions from aqueous media.

[2246] FIG. 254 illustrates PMMA decorated by NH.sub.3 1746 can be functionalized by radical 1747 comprising (RSO.sub.3).sup.Na.sup.+ in water to form PMMA 1748 with numerous O.sub.2HSR functional groups. The radical R can then be functionalized by hydroxide (OH) to produce SO.sub.3H ionomers. Other processes for sulfonating a PMMA nanosphere include conjugates:

[2247] FIG. 255 illustrates a process to create porous or collapsed PMMA nanospheres starting with MMA monomer 1760 polymerized by azobisisobutyronitrile (AlBN) to form PMMA nanosphere seed 1761. The PMMA seed is then swelled by soaking in benzoyl peroxide (BPO), ethylene glycol dimethacrylate (EGDMA), and by more MMA to create adult PMMA nanosphere 1762. Subsequent immersion in tetrahydrofuran (THF) etches pores in nanosphere 1763. A process for controlling the porosity of PMMA depends on the application of different porogen treatment on porous PMMA microspheres by seed swelling polymerization. Applications of these PMMA microspheres include their use in high-performance liquid chromatography.

[2248] The direct formation of nanoclusters, i.e. aggregates of nanospheres illustrated in FIG. 256A where methyl methacrylate (MMA) 1770 is combined with zinc acrylate (Zn(H.sub.2CCHCO.sub.2).sub.2) to form poly methyl methacrylate zinc (PMMA Zn NCs) nanoclusters 1772 with zinc in the Zn.sup.2+ divalent state. The final step, functionalization in hydrogen sulfide (H.sub.2S) gas produces a nanocluster 1773 of ZnS nanospheres bound by a PMMA matrix. The resulting structure is referred to as PMMA ZnS NCs. A related process for forming zinc PMAA is comprises multifunctional ionomer-derived honeycomb-patterned architectures used to enhance the performance of light-emitting diodes.

[2249] Made in accordance with this invention, the Zn.sup.21 zinc PMMA nanosphere 1772 can be functionalized in a two-step process comprising treatment in sodium hydroxide (NaOH) producing poly methyl methacrylate zinc hydroxide nanospheres (PMMA ZnOH NS) 1773h. Subsequently a H.sub.2O rinse followed by drying and heat treatment 100 C. converts zinc hydroxide (ZnOH) into zinc oxide (ZnO). The resulting nanocluster comprises an aggregate of poly methyl methacrylate zinc oxide nanospheres 1773o.

[2250] The zinc nanoparticles can may be added as an ionic filler into membranes comprising PFSA or PVA as inorganic ion exchange sites within the matrix improving conductivity and film stability. Unlike organic compounds, inorganic ion exchange sites cannot be detected using detected using absorbance spectroscopy so their presence and electrical activity is determined indirectly by measuring the electrical behavior of IEMs with and without the ZnO nanoparticle or PMMA-ZnO doping. They may be used in hydrogen PEM furl cells and direct methanol fuel cells (DMFCs).

[2251] PMMA polymers may form in various isometric arrangements of radical R groups. An isomer is a group of chemical having the same chemical formula and compositions but with different structural arrangements. Examples of PMMA isomers shown in FIG. 257 include the isotactic isomer 1774 where radicals appear topologically on the same side of the molecule, in the syndiotactic isomer 1775 where methane (CH.sub.3) groups and radicals R alternate, or in an atactic configuration 1776 where the radicals repeat in pairs. Various polymerizations of MMA isomeric moieties include efforts in transparent and stretchable active matrices functionalized by radicals R. In the structures shown, radicals R are neither catalytic nor ionomeric and are therefore not useful in ion exchange membranes for hydrolysis or fuel cells.

[2252] Made in accordance with this invention, poly methyl methacrylate (PMMA) polymers shown previously in FIG. 257 can be functionalized by various ionomeric radicals including hydrogen ions H.sup.+, sulfonic acid (SO.sub.3H), or sulphonated phenyl groups regardless of whether the PMMA is in the form of a membrane, film, nanosphere, or nanocluster. Methods in substitution chemistry able to convert a non-ionomeric radical into an proton exchange group by attaching ionized hydrogen (H.sup.+) groups, sulfonic acid (SO.sub.3H), sulfonated phenyl group (C.sub.6H.sub.6SO.sub.3), or other acids (not shown) such as boric acid (H.sub.3BO.sub.3), phosphoric acid (H.sub.3PO.sub.4), citric acid (CA), and benzenesulfonic acid (BzSA, BzSO.sub.3H, C.sub.6H.sub.6O.sub.3S), and others have been described previously and will not be repeated here. Poly(methyl methacrylate) may also form copolymers with or be grafted onto various other polymeric chains. In FIG. 258 for example PMMA 1778 is grafted onto polyester 1777 to form the grafted polymer PE-g-PMMA with ionomeric radicals 1779. Other PMMA moieties functionalized by an ionomeric radical R shown in FIG. 259 include pristine poly(methyl methacrylate) (PMMA) 1784; maleic anhydride (MAH) PMMA linear copolymer P(MMA-co-MAH) 1785; and the maleic anhydride derivative (MI) of MAH-PMMA linear copolymer P(MMA-co-MAH-co-Mi) 1786. Although such molecules are not intrinsically catalytic or ionomeric, made in accordance with invention all radical R groups may be substituted by a hydrogen acid group H.sup.+, by sulfonic acid (SO.sub.3H), by phenylated sulfonic acid (C.sub.6H.sub.6SO.sub.3), by boric acid (H.sub.3BO.sub.3), phosphoric acid (H.sub.3PO.sub.4), citric acid (CA), and benzenesulfonic acid (BzSA, BzSO.sub.3H, C.sub.6H.sub.6O.sub.3S), and others.

[2253] Another grafted polymer PMMA-g-PVDC 1789 is depicted in FIG. 260 where methyl methacrylate (MMA) 1788 is polymerized into a chain and grafted onto polyvinylidene fluoride (PVFC) 1787. FIG. 261 illustrates copolymerization of maleic anhydride (MAH) 1791 with methyl methacrylate (MMA) 1790 in benzoyl peroxide (BPO, (BzO).sub.2) and ethyl acetate (EtOAc, ETAC, C.sub.4H.sub.8O.sub.2) to produce the linear copolymer PMMA-co-MAH 1792. Without added steps, the process does not however produce ionomeric or catalytic PMMA, unless made in accordance with this invention the radical R groups are substituted by an ionomeric acid group such as phosphonic acid.

[2254] In summary, top view 3000 and membrane side view 3001 in FIG. 262 illustrate a variety of elements of ionomeric polymer 3002 comprising PMMA membranes, polymers, copolymers, and grafted polymers made in accordance with this invention, including separately or in combination inventive matter comprising: [2255] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2256] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2257] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2258] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2259] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2260] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2261] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2262] where ionomeric polymer 3002 is a copolymers and graft of poly(methyl methacrylate) including pure PMMA 1778; grafted polymers PE-g-PMMA 1779 and PVDC-g-PMMA 1789; and linear copolymers PMMA-co-MAH 1791, poly(MMA-co-MAH-co-Mi) 1786, and poly(MMA-co-MAH) 1785; and optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2263] where ionomeric polymer 3002 may comprise sidechains serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2264] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2265] where ionomeric polymer 3002 may include ionic fillers including PMMA nanosphere 1776 and PMMA nanoclusters 1773 including ZnS and ZnO; [2266] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2267] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2268] Hybrid poly(methyl methacrylate) structures include both PMMA membranes and PMMA fillers comprising copolymers and grafts. PMMA copolymer membranes include the tetra copolymer sulfobutyl-vinylimidazolium-trifluoro-methanesulfonate-co-methyl methacrylate (sBVlm-TfO-co-MMA).

[2269] Radical R functionalized PMMA membranes include grafts of poly(methyl methacrylate) with polyester (PMMA-g-PE) or with polyvinylidene fluoride (PMMA-g-PVDF), and copolymers with maleic anhydride P(MMA-co-MAH) and with maleic anhydride derivatives P(MMA-co-MAH-co-Mi). The radical* R may comprise hydrogen ions (H.sup.+), sulfonic acid (SO.sub.3H, SA), phenylated sulfonic acid (Ph-SA, C.sub.6H.sub.6SO.sub.3), phosphoric acid (PA, H.sub.3PO.sub.4), boric acid (BA, H.sub.3BO.sub.3), citric acid (CA, C.sub.6H.sub.8O.sub.7), and benzenesulfonic acid (BzSA, BzSO.sub.3H, C.sub.6H.sub.6O.sub.3S), and others.

[2270] The table below describes the construction of methyl methacrylate (MMA) and poly methyl methacrylate (PMMA) copolymers and grafted hybrid membranes:

TABLE-US-00040 ionomer structure endoskeleton solvents, X-L fillers 27. methyl methacrylate hybrid PMMA polymers: ABS, solv: Ac, tol, DCE, PMMA fillers: Pd copolymers and grafts copolymers SAN, ASA, EMA, MEK, DCM, NEth, PMMA NC, Pd sBVIm-TfO-co-MMA MBS, MABS, Anon, TCM, PhCl, P(MMA-PAA) NC, functionalized* PMMA MMA-VA Xylol, Anisole, sPMMA, PMMA- PE-g-PMMA pillars: DEP, PMA, EtOAc, SA, porous NS, PMMA-g-PVDC reinforcing fillers HCOOH PMMA NCs (ZnS, P(MMA-co-MAH) (C-fiber, CNTs) X-L: BPO, CTA, ZnO) P(MMA-co-MAH-co-Mi) tBPPiv other fillers: * R = H.sup.+, SA, Ph-SA, PA, sac filler, CNTs, BA, CA oxides, POSS, NPs, MOFs, PIL

[2271] Endoskeletal polymers able to form pillar links with PMMA membranes include acrylonitrile butadiene styrene (ABS) used for its toughness and impact resistance; styrene-acrylonitrile (SAN) a copolymer of styrene and MMA able to bond to PMMA because of shared constitutes; acrylonitrile-styrene-acrylate (ASA) a copolymer of acrylonitrile, styrene, and acrylate also derived from MMA; ethylene methyl acrylate (EMA) copolymerized from ethylene and MMA; methyl methacrylate-butadiene-styrene (MBS) combining MMA with butadiene and styrene; methyl methacrylate-acrylonitrile-butadiene-styrene (MABS) and tetra copolymer of MMA with acrylonitrile, butadiene, and styrene; and methyl methacrylate-vinyl acetate (MMA-VA) a copolymer of MMA with vinyl acetate offering superior adhesion and flexibility.

[2272] Solvents used in forming methyl methacrylate (MMA) polymers include acetone (Ac, C.sub.3H.sub.6O) toluene (tol, PhCH.sub.3, C.sub.6H.sub.5CH); dichloroethane (DCE, C.sub.2H.sub.2Cl.sub.2); butanone aka methyl ethyl ketone (MEK); cyclohexanone (Anon, C.sub.6H.sub.10O); nitroethane (NEth, C.sub.2H.sub.5NO.sub.2), chloroform (TCM, trichloromethane, CHCl.sub.3); dichloromethane (DCM, CHCl.sub.2) (or methylene chloride); benzene (Bz, C.sub.6H.sub.6); chlorobenzene (PhCl, C.sub.6H.sub.5Cl); xylene (Xylol, dimethylbenzene, C.sub.8H.sub.10); methoxybenzene aka anisole or phenyl methyl ether (CH.sub.3OC.sub.6H.sub.5); diethyl phthalate (DEP); methoxypropyl acetate (PMA, C.sub.6H.sub.12O.sub.3); ethyl acetate (EtOAc, C.sub.4H.sub.8O.sub.2); ethyl lactate (Acytol, lactic acid, C.sub.5H.sub.10O.sub.3); and formic acid (methanoic acid, HCOOH). Catalysts and reagents beneficial in polymerizing methyl methacrylate (MMA) hybrid membranes and cross linking them to other polymers include benzoyl peroxide (BPO, (BzO).sub.2), tert-butyl peroxypivalate (tBPPiv), thiol-containing chain transfer agents (CTAs).

[2273] PMMA based fillers as described include the palladium doped catalytic nanoclusters Pd PMMA and Pd P(MMA-PAA), sulfonated nanospheres sPMMA and PMMA-SA, zinc doped nanoclusters ZnS, ZnOH, and ZnO PMMA, and inert porous nanospheres. Other membrane fillers and dopants were described previously and for brevity's sake, will not be repeated here.

28. Functionalized Hybrid Carboxy Methyl Cellulose (CMC) Polymer IEMs.

[2274] Given the propensity for ionomer fouling and fuel cross-over in direct methanol fuel cells (DFMCs) one alternative membrane to PFSA comprises a tri-copolymer of carboxy methyl cellulose (CMC) with polyvinyl alcohol (PVA). Carboxy methyl cellulose is a polysaccharide comprising a flexible water soluble polymeric matrix containing hydroxyl and sodium carboxymethyl groups (CH.sub.2COONa) derived from fibrous plant tissue. CMC beneficial material properties include biodegradability, nontoxicity, high hydrophilicity, biocompatibility and excellent film forming ability. A variety of CMC applications include its use in textiles, drugs, detergents, purification and flocculation, food processing, and more.

[2275] As a cellulose molecule, CMC suffers from limited stability and poor miscibility. By blending it with polyvinyl alcohol (PVA), CMC forms a copolymer offering increase its physicochemical properties such as miscibility, tensile strength, and higher ionic conductivity than CMC alone. Unfortunately the CMC-co-PVA copolymer is still electrically uncompetitive to other ionomeric membranes. To improve membrane conductivity, the copolymer can be mixed with acrylamide making it better suited for electrochemical applications.

[2276] FIG. 263 illustrates a matrix comprising CMC mainchain 1795b with PMA backbones 1295a and 1295a, and pendants of AA polymers 1794. The polymer backbones are bond together by hydrogen bonds 1799 resulting in a carboxy-methyl-cellulose-PVA-acrylamide copolymer (CMC-co-PVA-co-AA). The graphic also provides mechanistic depiction of putative proton conduction mechanisms in the sulfonated poly (vinyl alcohol)/carboxy methyl cellulose/acrylamide-based hybrid polyelectrolyte membrane. As shown, transport of H.sup.+ ions may occur through charge hopping among sulfonic acid ionomers 1054 or by vehicular transport of hydronium ions (H.sub.3O) 1796 combining water 1797 with H.sup.+ ions.

[2277] Film conductance may be further enhanced by ionomeric fillers 1798 comprising sulfonated activated carbon (SAC) or carboxylated carbon nanotubes (CCNT) or by doping with ionic liquids, all three of which may diffuse out of the membrane. In one embodiment of the invention the permanent fillers are constrained within the polymer matrix laterally by the endoskeletal pillar matric and perpendicular to the film by a nanocoatings. Alternatively CMC can be copolymerized with propylene carbonate (PC) and ammonium chloride. Proton conduction in CMC-co-PC is facilitated through dissociation of H.sup.+ from ammonium chloride (NH.sub.4Cl) or alternatively from ammonium bromide (NH.sub.4Br).

[2278] The table below describes the construction of carboxy methyl cellulose (CMC) copolymer hybrid membranes:

TABLE-US-00041 ionomer structure endoskeleton solvents, X-L fillers 28. carboxy methyl hybrid CMC polymers: PAM, PVA, solv: water, IPA, IBA, CMC fillers: cellulose copolymers copolymers PEO, PEG, PAA, PVP EtOH SAC, CCNT CMC-co-PVA pillars: reinforcing X-L: HCOOH, AcOH, other fillers: CMC-co-PVA-co-AA fillers (C-fiber, CNTs) H.sub.2CO.sub.3, pyr, glycolic, sac filler, CNTs, CMC-co-PCNH.sub.4Cl acid, butyric acid, oxides, POSS, CMC-co-PCNH.sub.4Br Acytol NPs, MOFs, PIL

[2279] Hybrid carboxy methyl cellulose (CMC) membranes include copolymers of CMC with polyvinyl alcohol (PVA), acrylamide (AA), and polycarbonate (PC) doped with NH.sub.4Cl or NH.sub.4Br. Endoskeletal polymers bondable to CMC polymers include polyacrylamide (PAM) able to form composites; polyvinyl alcohol (PVA) present in the copolymer; polyethylene oxide (PEO); polyethylene glycol (PEG) through hydrogen bonding forming hydrogels; and polyvinylpyrrolidone (PVP). Solvents used in forming carboxy methyl cellulose (CMC) copolymers include water, isopropanol (IPA), isobutanol (IBA), and ethanol (EtOH).

[2280] Catalysts and reagents beneficial in carboxy methyl cellulose (CMC) hybrid membranes and cross linking them to other polymers include citric acid (C.sub.6H.sub.5(O.sub.7).sup.3) and carboxylic acids, i.e. acids containing carboxyl (COOH) functional group. Carboxylic acids include formic acid (methanoic acid, HCOOH), carbonic acid (hydroxymethanoic acid, H.sub.2CO.sub.3), acetic acid (AcOH), glycolic acid (C.sub.2H.sub.4O.sub.3), ethyl lactate (Acytol, lactic acid, C.sub.5H.sub.10O.sub.3), pyruvic acid (Pyr, C.sub.3H.sub.4O.sub.3), butyric acid (C.sub.3H.sub.7COOH), and others. CMC specific filers include sulfonated activated carbon (SAC) or carboxylated carbon nanotubes (CCNT). Other membrane fillers and dopants were described previously and for brevity's sake, will not be repeated here.

29. Functionalized Hybrid Multi-Acid Sidechain (MASC) Polymer IEMs.

[2281] Rather than modifying the backbone of a polymer, an alternative approach to improve IEM performance over that offered by PFSA or Nafion is to modify the construction of the pendant attaching the ionomer terminus to its polymer mainchain. Potential benefits of substituting the fluorocarbon pendant of 3M, Nafion or Aquivion with an alternative sidechain containing fewer hydro-fluorine groups is to adjust the film morphology and crystallinity to control swelling, water update, and fuel crossover, especially in direct methanol fuel cells (DMFCs). Generally the modification comprises a substitution of one ore more

[2282] As shown in FIG. 264, a polymer backbone 1800 common to PFSA includes TFE repeated region 1802 and pendant link section 1801. The pendant comprises a z-repeated segment of (CF.sub.2).sub.z and x-repeated segment of (CF.sub.2).sub.x surrounding a central core of HN 1807 linearly enclosed by two SO.sub.2 radicals. Together, the HNSO.sub.2 pendant substitute is referred to as a multi-acid sidechain (MASC) 1803. Combined with an ionomeric sulfonic acid group 1806, the MASC 1803 side group is referred to as perfluoro imide acid or PFIA.

[2283] The technical report by the US Dept. of Energy consider that by adjusting the length of the MASC sidechain the film's properties prospectively may be varied. FIG. 265A illustrates a MASC can extended by successive repeated processes. For example, starting with imide acid precursor 1810, the first process step shown involves conversion of SO.sub.2NH.sub.2 terminus 1811 into SO.sub.2F 1820 during which time a sulfonyl fluoride group (SO.sub.2NHSO.sub.2) 1812 is inserted into the carbon sidechain. In the case of sidechain 1813 the sulfonyl fluoride is positioned three carbons from the SO.sub.2F terminus while in sidechain 1814 the sulfonyl fluoride is positioned four carbons from the SO.sub.2F terminus.

[2284] The relative position of the sulfonyl fluoride group within the sidechain remains unchanged in subsequent processing steps including (a) conversion of SO.sub.2F terminus 1820 into SO.sub.2H terminus 1821, (b) conversion of SO.sub.2H terminus 1821 into SO.sub.2NH.sub.2 terminus 1822, and (c) conversion of SO.sub.2NH.sub.2 terminus 1822 into (SO.sub.2NHSO.sub.2) terminus 1823. Notice this structure is identical to that of sulfonyl fluoride group (SO.sub.2NHSO.sub.2) 1812 except that the group is positioned farther along a longer the sidechain. These longer MASC structures mat be referred to as perfluoro-ionone chain extended (PFICE) ionomeric polymers.

[2285] Direct synthesis of PFIA from PFSA is illustrated in FIG. 265B where PFSA precursor 1800p comprising PTFE segment 1802 and pendant section 1801 with NH.sub.2 terminus are treated by reagent to form perfluoro bis(sulfonyl)imide-acid (PFIA) 1800g. As shown the PFIA 1800h comprises TFE segment 1802 and graft segment 1801g with multi acid sidechain (MASC) 1803y containing sulfonyl fluoride group (SO.sub.2NHSO.sub.2) 1807 and sulfonic acid (SO.sub.3H) ionomer 1054.

[2286] Direct synthesis of a related MASC polymer is illustrated in FIG. 265C. Starting with the same PFSA precursor 1800p, treatment by phenyl reagent 1815 results in 2-sulfobenzene bissulfonylimide, aka ortho-biz acid 1800q including TFE segment 1802 and grafted segment 1801q where multi-acid sidechain (MASC) 1803q attaches to the polymer mainchain. As shown sidechain MASC 1803q includes the same sulfonyl fluoride group (SO.sub.2NHSO.sub.2) 1807 but with a different terminus comprising phenyl 1816 and sulfonic acid (SO.sub.3H) ionomer 1054.

[2287] In summary, membrane top view 3000 and membrane side view 3001 in FIG. 266 illustrate a variety of elements of ionomeric polymer 3002 comprising multi acid sidechains made in accordance with this invention, including separately or in combination inventive matter comprising: [2288] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2289] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2290] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2291] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2292] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2293] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2294] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2295] where ionomeric polymer 3002 comprises a TFE mainchain optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2296] where ionomeric polymer 3002 may comprise multi-acid sidechain 1803 serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane including perfluoro imide acid (PFIA), perfluoro-ionone chain extended (PFICE) polymers, or 2-sulfobenzene bissulfonylimide (ortho-bis acid); [2297] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2298] where ionomeric polymer 3002 may include embedded ionic fillers of electrospun nanofiber mats blending perfluoro imide acid and polyvinyl difluoride (PFIA-PVDF) or perfluoro imide acid and perfluorinated sulfonic acid (PFIA-PFSA); [2299] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2300] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.

[2301] The table below describes the construction of multi acid sidechain (MASC) copolymer hybrid membranes based on a variety of ionomeric mainchains:

TABLE-US-00042 ionomer structure endoskeleton solvents, X-L fillers 29. multi-acid sidechain MASC hybrid polymer: solv: catalysts, used sac filler, CNTs, modified polymers polymer matched to IEM in forming polymers oxides, POSS, PFIA-PFSA MASC polymer. match membrane, NPs, MOFs, PIL PFIA-PTFE MASC pillar: reinforcing not filler ortho-bis acid MASC fillers (C-fiber, X-L: reagents PFIA-co-PVA-co-PTFE CNTs) matching PFIA-co-SPAES, sPEEK, membrane sPEES polymer PFIA-co-sPVA, sPBI, sCS

[2302] Endoskeletal pillars should be chosen to bond to the mainchain polymer to which the PFIA or MASC attaches. Solvents used in forming multi-acid sidechains (MASC) modified copolymers are chosen to be compatible with the polymer mainchain. If for example the mainchain comprises a MASC modified PFSA homopolymer or a PFSA-PTFE, then solvents compatible with PFSA-PTFE are preferred. Similarly catalysts and reagents beneficial in multi-acid sidechains (MASC) hybrid membranes and cross linking them to other polymers are selected to match the polymer mainchain, not the pendant. Membranes fillers and dopants were described previously and for brevity's sake, will not be repeated here.

30. Functionalized Hybrid Arylene Ether (PAE) Polymer IEMs.

[2303] Another class of thermoplastic polymers, poly(arylene ether)s (PAEs) have been developed for water filtration including oil/water separation, desalination, and wastewater treatment, which involve the removal of heavy metal ions, dyes, oils, and other organic pollutants. Beneficial characteristics of PAEs include corrosion resistance, high-temperature resistance, anti-fouling properties, and durability in challenging environments. Although limited, some effort has been made to adapt these compounds to form ionomeric membranes. While section 13 considered functionalization of pristine poly arylene ether, synthesis of hybrid PAE blends confers beneficial morphological and electrical properties to proton exchange membrane (PEM) chemistry than pure PAE films cannot offer.

[2304] Ionomer membranes produced from hexaarylbenzene-based partially fluorinated poly(arylene ether) blends involve combining sulfonated poly(arylene)s and highly rigid hexaarylbenzene (HAB, HABz) derivatives with cardo structured fluorenyl, i.e. where the pendent groups comprise chains of aromatic rings such as phenyl, benzene, etc. In three dimensions, these pendent groups are necessarily orthogonal to the plane of the mainchain irrespective as to whether the polymer backbone also comprises aromatic rings. To promote rapid growth a high-boiling-point solvent such as dimethyl sulfoxide (DMSO) is also required.

[2305] FIG. 267 illustrates a process for combining two different PAE polymers, (12F9B-DF) 1820 and (7BDO) 1821, with toluene, dimethylacetamide (DMAc), and potassium carbonate (K.sub.2CO.sub.3) to form hybrid heteropolymer (P12F97B) 1822. Polymerized difluoro monomer (4,4-difluoro-3,3-bis(trifluoromethyl)-2,3,5,6,4,4-difluoro-3,3-bis(trifluoromethyl) 2,3,5,6-tetra (trifluoro methyl) phenyl-[1,1:4,1:4,1:4,1-quinquephenyl forms ionomer (12F9B-DF) 1820.

[2306] Ionomer (7BDO) 1821 comprises polymerized diphenol monomer 2,3-diphenyl-[1,1:4,1:4,1:4,1-quinquephenyl]-4,4-diol. The resulting polymer (P12F97B) 1822 is then functionalized by chlorosulfonic acid (CIHO.sub.3S) and dichloromethane (DCM) to produce sulfonated PAE polymer s(P12F97B) 1823 including ionomer sulfonic acid (SO.sub.3H) 1054.

[2307] FIG. 268 illustrates a process for combining two different PAE polymers, (6F9B-DF) 1824 and (6BDO) 1825 with toluene, dimethylacetamide (DMAc), and potassium carbonate (K.sub.2CO.sub.3) to form hybrid heteropolymer (P6F9CB) 1826. Specifically PAE polymer (6F9B-DF) is synthesized from polymerization of a monomer comprising polymerization of 4,4-difluoro-3,3-bistrifluoromethyl-2,3,5,6-tetraphenyl-[1,1;4,1;4,1;4,1]-pentaphenyl. For the second reactant, CBDO 1825 is synthesized by the polymerization of diphenol monomer 4,4-(9-fluorenylidene)diphenol. The resulting polymer (P6F9CB) 1826 is then functionalized by chlorosulfonic acid (CIHO.sub.3S) and dichloromethane (DCM) to produce sulfonated PAE polymer s(P6F9CB) 1827 including ionomer sulfonic acid (SO.sub.3H) 1054.

[2308] FIG. 269 illustrates one lexicological convention used in naming hybrid PAE polymers. As shown hydrophobic segments 1830 and 1835 containing CF.sub.3 groups are named 12F and 6F respectively by counting the number of fluorine atoms. Both moieties contain 9 benzene rings. Alternatively for the hydrophilic segments 1831 and 1836, the number of benzene rings of in the former is seven hence its naming 7B, and in the later is a cardo structured benzene named as CB although a more accurate term should be 2CB.

[2309] Using this somewhat confusing naming system, the sulfonated PAE polymer 1852 containing segments 12F and 7B is referred to as P12F9B7B which has been shortened to P12F97B. To remain consistent with this document the prefix of a lower case s is used to denote that segment 1851 is sulfonated, hence its name s7B as is the case for the resulting polymer, vis--vis sP12F97B. Similarly polymer 1837 containing segments s6F and sCB is named s6F9CB but for accuracy should be s6F9B2CB.

[2310] Membrane top view 3000 and membrane side view 3001 in FIG. 270 illustrate a variety of elements of ionomeric polymer 3002 hybrid PAE heteropolymer made in accordance with this invention, including separately or in combination inventive matter comprising [2311] an ion exchange membrane 3003 comprising one or more polymeric backbone chains 3009c including ionomers 3009i present along the backbone chains or connected to the mainchain via a pendant sidechain; and/or [2312] a semi-rigid network of pillars comprising a wide exoskeleton 3004x and a grid pattern of a thinner endoskeleton 3004e, where the exoskeleton shown in top view 3003 may be cut mechanically or cut by laser to singulate the membrane from other membranes fabricated in the same film sheet; [2313] where the pillars comprise a reinforced core 3007 containing carbon fiber or plastic shards optionally surrounded by adhesive or molecular glue 3008; [2314] where the polymer chain 3009c is chemically attached to pillar's core 3007 by pillar link 3006 which may include adhesive or molecular glue 3008 to facilitate attachment; [2315] where the pillars form a skeletal structure circumscribing multiple panes of membrane 3003 providing mechanical support and limiting membrane 3003 deformation due to water absorption or dehydration; [2316] where membrane 2003 may include sac-pores 3005 interrupting the lattice periodicity of membrane 3003 by the previous introduction of a sacrificial filler prior to molding and its subsequent removal post-casting by a solvent leaving a hole in place of the sac-filler; and/or [2317] where an optional nanocoating (not shown) is formed atop membrane 3003 to either enhance membrane conductivity, increase the rate of oxygen reduction reactions (ORR) in the cathode, or provide protection against membrane poisoning including boron nitride or other materials that inhibit the diffusion of carbon monoxide (CO) into the catalyst layer; [2318] where ionomeric polymer 3002 comprises poly (arylene-ether) in the linear copolymer chain topologies sP12F97B a1832 or more accurately sP12F8B7B and sP6F9CB 1837 more accurately sP6F9B2CB, optionally blended with other homopolymers, heteropolymers, copolymers, thereby controlling varying degrees of film crystallinity and anisotropy to form a hybrid copolymer; [2319] where ionomeric polymer 3002 may comprise multi-acid sidechain 1803 serving as pendants and influencing crystalline regularity, porosity, conductivity, and fuel crossover of the membrane; [2320] where ionomeric polymer 3002 may comprise an ionomer 3009i of reactive sulfonic acid R group SO.sub.3H, SO.sub.3Na, and sulfobutyl groups; [2321] where ionomeric polymer 3002 may include embedded ionic fillers; [2322] where ionomeric polymer 3002 may comprise carboxylic acid groups COOH, phosphonic acid groups PO.sub.3H.sub.2, phosphoric acid group PO.sub.4H.sub.2, imide groups CONH, quaternary ammonium groups NR.sub.3.sup.+, pyridinium groups C.sub.5H.sub.5N.sup.+, imidazolium groups C.sub.3H.sub.3N.sub.2.sup.+; tetraalkylammonium groups NR4.sup.+; phenolic hydroxyl groups OH, or any other acidic group which easily ionizes to donate conducting cations of H.sup.+, Na.sup.+, or K.sup.+ into the solid electrolyte; and finally [2323] where the combination of the endoskeletal pillars and the membrane coating are used to seal in any ionic liquid doping to prevent seepage, leakage, or IL depletion.