Polymer electrolyte membrane for use, e.g. in fuel cells, obtained by heating a mixture of phosphonated aromatic polyazole monomers in polyphosphoric acid and then processing to form a self-supporting membrane

摘要

Proton-conducting, polyazole-based polymer membranes are obtained by heating a mixture of (hetero)aromatic monomers (tetra-amino compounds and polycarboxylic acids, or diamino-carboxylic acids, at least some of which have phosphonic acid groups) in polyphosphoric acid at up to 350degreesC and then processing to form a self-supporting membrane. A proton-conducting polymer membrane containing polyazoles with phosphonic acid groups, obtained by (A) mixing (hetero)aromatic tetra-amino compounds with (hetero)aromatic carboxylic acids containing at least two acid groups (or their derivatives), where at least part of the amino and/or acid compounds have at least one phosphonic acid group, or mixing (hetero)aromatic diaminocarboxylic acids (at least part of which contains phosphonic acid groups) in polyphosphoric acid (PPA) to form a solution and/or dispersion, (B) heating at up to 350degreesC under inert gas to form polyazoles, (C) coating the mixture from (A) and/or (B) onto a support and (D) treating the membrane thus formed until it is self-supporting. Independent claims are also included for (1) electrodes with a conductive polymer coating, obtained by the above process but using an electrode as the support in step (C) (2) membrane-electrode units comprising electrode(s) and membrane(s) as above (3) fuel cells containing such membrane-electrode units