Crosslinked membranes for anion exchange applications, and methods of making and using the same, are described.

Crosslinked membranes for anion exchange applications, and methods of making and using the same, are described.

A new polyelectrolyte multilayer coated proton-exchange membrane for electrolysis and fuel cell applications has been developed for electrolysis and fuel cell applications. The polyelectrolyte multilayer coated proton-exchange membrane comprises: a cation exchange membrane, and a polyelectrolyte multilayer coating on one or both surfaces of the cation exchange membrane. The polyelectrolyte multilayer coating comprises alternating layers of a polycation polymer and a polyanion polymer. The polycation polymer layer is deposited on and is in contact with the cation exchange membrane. The top layer of the polyelectrolyte multilayer coating can be either a polycation polymer layer or a polyanion polymer layer.

A polyelectrolyte multilayer membrane has been developed for redox flow batteries and other electrochemical reaction applications. The polyelectrolyte multilayer membrane comprises an ionically conductive thin film composite membrane comprising a microporous support membrane, a hydrophilic ionomeric polymer coating layer on the surface of the microporous support membrane, and a polyelectrolyte multilayer coating on the second surface of the hydrophilic ionomeric polymer coating layer (the side opposite the support membrane). The polyelectrolyte multilayer coating comprises alternating layers of a polycation polymer and a polyanion polymer. Methods of making the polyelectrolyte multilayer membrane and redox flow battery system including the polyelectrolyte multilayer membrane are also described.

A composite electrolyte membrane having a composite layer that is a composite of a hydrocarbon polymer electrolyte and a fluorine-containing polymer porous substrate, wherein a fractal dimension D exhibiting the distribution of the hydrocarbon polymer electrolyte and the fluorine-containing polymer porous substrate in the composite layer is 1.7 or more. An object of the present invention is to enable a composite electrolyte membrane composed of a hydrocarbon polymer electrolyte and a fluorine-containing polymer porous substrate to achieve high proton conduction ability and high mechanical durability.

Improved membrane electrode assemblies, cation-associating components thereof, and methods of making and treating the same are provided. Membrane electrode assemblies may include an ionomer having a first pKa value, and a water-insoluble net polymer having a weakly-acidic functional group, wherein the weakly-acidic functional group has a second pKa value greater than the first pKa value.

Improved membrane electrode assemblies, cation-associating components thereof, and methods of making and treating the same are provided. Membrane electrode assemblies may include an ionomer having a first pKa value, and a water-insoluble net polymer having a weakly-acidic functional group, wherein the weakly-acidic functional group has a second pKa value greater than the first pKa value.

[Problem] Provided is a proton-conducting membrane that exhibits high proton conductivity even in low-humidity or anhydrous environments.

[Solving means] A proton-conducting membrane that comprises a crosslinked polymer and a plasticizer, wherein the crosslinked polymer contains repeating units containing proton-donating groups in an amount equal to 10 mol % or more of repeating units constituting the crosslinked polymer, and at least 60 mass % of the plasticizer is a proton-donating compound with a pKa of 2.5 or less, and, the proton-conducting membrane is a viscoelastic solid in the temperature range of from 20° C. to 125° C.

[Problem] Provided is a proton-conducting membrane that exhibits high proton conductivity even in low-humidity or anhydrous environments.

[Solving means] A proton-conducting membrane that comprises a crosslinked polymer and a plasticizer, wherein the crosslinked polymer contains repeating units containing proton-donating groups in an amount equal to 10 mol % or more of repeating units constituting the crosslinked polymer, and at least 60 mass % of the plasticizer is a proton-donating compound with a pKa of 2.5 or less, and, the proton-conducting membrane is a viscoelastic solid in the temperature range of from 20° C. to 125° C.

An object of the present invention is to provide, in the manufacture of a membrane-catalyst assembly including a polymer electrolyte membrane and a catalyst layer bonded to the polymer electrolyte membrane, a method that achieves both the relaxation of thermocompression bonding conditions and the improvement of adhesion between the catalyst layer and the electrolyte membrane with high productivity. A main object of the present invention is to provide a method of manufacturing a membrane-catalyst assembly including an electrolyte membrane and a catalyst layer bonded to the electrolyte membrane, the method including a liquid application step of applying a liquid to a surface of the catalyst layer before bonding, and a thermocompression bonding step of bonding, to the electrolyte membrane, the catalyst layer to which the liquid is applied by thermocompression bonding.