ELECTROLYTE MATERIAL, LIQUID COMPOSITE, AND MEMBRANE ELECTRODE ASSEMBLY FOR SOLID POLYMER FUEL CELLS

摘要

Provided is an electrolyte material that can inhibit increases in moisture content even if the ion exchange capacity of a polymer is high, said polymer having repeating units based on a monomer having a dioxolane ring. Also provided is a membrane electrode assembly that has excellent power-generation characteristics regardless of whether the level of humidification is low, none, or high. The electrolyte material comprises a polymer (H), having an ion exchange capacity of at least 1.35 mEq per gram of dry resin, in which a precursor group of another polymer (F) is converted into an ion exchange group. The latter polymer (F) has: repeating units (A) based on a perfluoromonomer that has a dioxolane ring and a precursor group of an ion exchange group; and repeating units (B) based on a perfluoromonomer that has a dioxolane ring but does not have a precursor group. If said polymer (F) is melt-extruded at an extrusion pressure of 2.94 MPa from a nozzle that is 1 mm long and has an inside diameter of 1 mm, the temperature TQ such that the amount extruded is 100 mm3/sec is at least 200°C.