An ion exchange membrane has multiple layers of ionic polymers which each contain substantially different chemical compositions. i.e. varying side chain lengths, varying backbone chemistries or varying ionic functionality. Utilizing completely different chemistries has utility in many applications such as fuel cells where for example, one layer can help reduce fuel crossover through the membrane. Or one layer can impart substantial hydrophobicity to the electrode formulation. Or one layer can selectively diffuse a reactant while excluding others. Also, one chemistry may allow for impartation of significant mechanical properties or chemical resistance to another more ionically conductive ionomer. The ion exchange membrane may include at least two layers with substantially different chemical properties.

The present invention relates to a self-humidifying ion-exchange composite membrane including an aromatic hydrocarbon polymer ion-exchange membrane formed on the surface of a porous polymer support and a thin hydrophobic coating layer having a nanocracked morphology pattern on the surface of the ion-exchange membrane. The self-humidifying ion-exchange composite membrane of the present invention has good thermal/chemical stability, high mechanical strength, high ion-exchange capacity, and good long-term operational stability. Particularly, the self-humidifying ion-exchange composite membrane of the present invention is able to self-hydrate even under high-temperature and low-humidity conditions. Due to these advantages, it is expected that the self-humidifying ion-exchange composite membrane of the present invention will be commercialized as an electrolyte membrane for a fuel cell or a membrane for water treatment.

To provide an ion exchange membrane which is excellent in dimensional stability in an in-plane direction when immersed in an electrolytic solution, and a method for producing a dry ion exchange membrane.

The ion exchange membrane according to the present invention is an ion exchange membrane containing a fluorinated polymer, wherein in a case where by Raman spectroscopy, polarized light orthogonal to the thickness direction of the ion exchange membrane is irradiated to obtain a spectrum chart, whereby the ratio of the peak area a2 of Raman shift 680 to 760 cm.sup.1 to the peak area al of Raman shift 1,025 to 1,095 cm.sup.1 is taken as A1, and by Raman spectroscopy, to a cross section in the thickness direction of the ion exchange membrane, polarized light parallel with the thickness direction is irradiated to obtain a spectrum chart, whereby the ratio of the peak area b2 of Raman shift 920 to 1,025 cm.sup.1 to the peak area b1 of Raman shift 1,025 to 1,095 cm.sup.1 is taken as B1, B1/A1 is at least 1.05.

A polymer electrolyte membrane of the present disclosure comprises a perfluorosulfonic acid resin (A), wherein the polymer electrolyte membrane has a phase-separation structure having a phase where fluorine atoms are detected in majority and a phase where carbon atoms are detected in majority, in an image of a membrane surface observed under an SEM-EDX, and the polymer electrolyte membrane has a phase having an average aspect ratio of 1.5 or more and 10 or less in an image of a membrane cross-section observed under an SEM.

An ion exchange membrane includes a matrix including a fluorinated polymer and a filler including cellulose nanocrystals. A method of making the ion exchange battery includes coating a solution including the fluorinated polymer and the cellulose nanocrystals onto a substrate, removing solvent from the coated substrate to provide the membrane, and removing the membrane from the substrate. The ion exchange membrane can be useful for a variety of applications including fuel cells, sensors, electrolytic cells, redox flow batteries, gas separators, humidifiers, and metal ion batteries.

A composite membrane includes an ion-conductive polymer layer; and a plurality of gas blocking inorganic particles non-continuously aligned on the ion-conductive polymer layer, wherein the composite membrane has a radius of curvature of about 10 millimeters or less.

To provide a production method whereby an ion exchange membrane for alkali chloride electrolysis can be obtained which has high current efficiency, little variation in current efficiency and high alkaline resistance. This is a method for producing an ion exchange membrane 1 having a layer (C) 12 containing a fluorinated polymer (A) having carboxylic acid type functional groups, by immersing an ion exchange membrane precursor film having a precursor layer (C) containing a fluorinated polymer (A) having groups convertible to carboxylic acid type functional groups, in an aqueous alkaline solution comprising an alkali metal hydroxide, a water-soluble organic solvent and water, and converting the groups convertible to carboxylic acid type functional groups to carboxylic acid functional groups, wherein the concentration of the water-soluble organic solvent is from 1 to 60 mass % in the aqueous alkaline solution (100 mass %); the temperature of the aqueous alkaline solution is at least 40 C. and less than 80 C.; and the proportion of structural units having carboxylic acid type functional groups in the fluorinated polymer (A) is from 13.0 to 14.50 mol % in all structural units (100 mol %) in the fluorinated polymer (A).

A resin composition for fabricating a separator which is easy to control viscosity, a method of preparing the same, and a battery including the same, are disclosed.

A composite membrane includes an ion-conductive polymer layer; and a plurality of gas blocking inorganic particles non-continuously aligned on the ion-conductive polymer layer, wherein the composite membrane has a radius of curvature of about 10 millimeters or less.

To provide a method whereby it is possible to efficiently produce an ion exchange membrane for alkali chloride electrolysis, which has high current efficiency and high alkali resistance at the time of electrolyzing an alkali chloride. This is a method for producing an ion exchange membrane 1 for alkali chloride electrolysis, having a layer (C) 12 containing a fluorinated polymer (A) having carboxylic acid type functional groups, by immersing an ion exchange membrane precursor film having a precursor layer (C) containing a fluorinated polymer (A) having groups convertible to carboxylic acid type functional groups, in an aqueous alkaline solution comprising an alkali metal hydroxide, a water-soluble organic solvent and water, and subjecting the groups convertible to carboxylic acid type functional groups to hydrolysis treatment to convert them to carboxylic acid type functional groups, wherein the concentration of the water-soluble organic solvent is from 1 to 60 mass % in the alkaline aqueous solution (100 mass %); the proportion of structural units having carboxylic acid type functional groups in the fluorinated polymer (A) is from 14.00 to 14.50 mol %; and the resistivity in the layer (C) 12 is from 3.010.sup.3 to 25.010.sup.3 .Math.cm.