TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Starting Materials: Amines of formula (H2N)4ArYpZr (A) and acids of formula (XOC)2ArYpZr (B), in whichAr = a (hetero)aromatic group;Y = a single bond or a group with 1-20 carbon atoms;p, r = 1-4;Z = a group of formula -SO3H or -C(R1)(SO3H)2;X = halogen or OR2;R1, R2 = H or a 1-20C group. Preferred compounds comprise:(a) 3,3,4,4-tetra-amino-biphenyl, 2,3,5,6-tetra-amino-pyridine and/or 1,2,4,5-tetra-aminobenzene;(b) (hetero)aromatic di-acids or their derivatives, e.g. phthalic, isophthalic, terephthalic acids and various substituted derivatives thereof, diphenic acid, naphthalenedicarboxylic acids, benzophenone-4,4-dicarboxylic acid, biphenyl-4,4-dicarboxylic acid, 4-carboxycinnamic acid etc. (35 di-acids listed);(c) 2,3-diamino-5-carboxyphenylsulfonic acid and 2,3- or 3,4-diamino-6-carboxyphenylsulfonic acid;(d) tri- or tetra-acids and their derivatives, especially e.g. trimesic, trimellitic, benzene-1 ,2,4,5-tetracarboxylic or naphthalene-1,2,4,5-tetracarboxylic acid etc. (14 acids listed), in amounts of 0-30 (preferably 0.5-10) mol% based on the amount of di-acid;(e) heteroaromatic acids, preferably pyridine-2,5-, -3,5-, -2,6- or -2,4-dicarboxylic acid, similar derivatives of pyrazole, pyrimidine, pyrazine or benzimidazole, pyridine-2,4,6-tricarboxylic acid, etc. (10 acids listed);(f) diaminobenzoic acids and/or their mono- and di-hydrochlorides.    TECHNOLOGY FOCUS - POLYMERS - Preferred Method: The solution prepared in step (A) may also contain dispersed and/or suspended polymer. Step (B) involves heating after forming a sheet of material as in (C). Step (D) involves treatment for 10 seconds to 300 hours at 0-150degreesC in presence of moisture, and the membrane obtained after (D) is crosslinked by the action of oxygen. A layer with a thickness of 20-4000 microns is formed in step (C) and the membrane formed in (D) has a thickness of 15-3000 microns. Electrodes made by this method have a conductive polymer coating with a thickness of 2-3000 microns.