PROTON-CONDUCTING POLYMER MEMBRANE COMPRISING SULFONIC ACID GROUP-CONTAINING POLYAZOLE, AND USE THEREOF IN FUEL CELL

PROBLEM TO BE SOLVED: To provide novel polymer electrolyte membranes. SOLUTION: Proton-conducting polymer membranes comprise sulfonic acid group-containing polyazoles and can be obtained by a method comprising the following steps of (A)-(D): (A) one or more aromatic and/or heteroaromatic tetra-amino compound/s is/are mixed with one or several aromatic and/or heteroaromatic carboxylic acid/s or the derivatives thereof, which contain at least two acid groups per carboxylic acid monomer, at least a part of the tetra-amino compounds and/or the carboxylic acids comprising at least one sulfonic acid group, or one or more aromatic and/or heteroaromatic diaminocarboxylic acid/s, at least a part of which contain sulfonic acid groups, is/are mixed in polyphosphoric acid so as to form a solution and/or dispersion; (B) the solution and/or dispersion obtained in step (A) is/are heated to temperatures of up to 350°C under inert gas so as to form polyazole polymers having benzimidazole units; (C) a layer is applied to a support using the mixture according to step (A) and/or (B); and (D) the membrane formed in step (C) is treated in the presence of moisture or water and/or water vapor at a temperature within a range of 0-150°C until the membrane is made self-supporting. COPYRIGHT: (C)2011,JPO&INPIT