Patent ID: 7795372

Claim:
A polymer film based on polyazoles which is obtained by a process comprising the steps A) mixing one or more aromatic tetramino compounds with one or more aromatic carboxylic acids or esters thereof which contain at least two acid groups per carboxylic acid monomer, or mixing of one or more aromatic or heteroaromatic diaminocarboxylic acids, in polyphosphoric acid to form a solution or dispersion, B) applying a layer using the mixture from step A) to a support, C) heating the layer obtained according to step B) under inert gas at temperatures of up to 350° C. to form a polyazole polymer, wherein the polyazole polymer has an intrinsic viscosity of at least 1.4 dl/g, D) treating the polymer film formed in step C) until it is self-supporting, E) detaching the polymer film formed in step D) from the support, F) removing the polyphosphoric acid or phosphoric acid present and drying.