PREPARATION AND CHARACTERIZATION OF SOLUBLE SULFONATED POLYBENZIMIDAZOLE FOR PROTON EXCHANGE MEMBRANE MATERIALS

A series of sulfonated polybenzimidazoles(sPBI-SF)were prepared from 2,2-bis(4-carboxyphenyl)hexafluoro- propane(BIS-B-AF),3,3′-disulfonyl-4,4′-dicarboxyldiphenylsulfone(DSDCDPS)and 3,3′-diaminobenzidine(DAB)at various stoichiometric ratio by solution copolycondensation in poly(phosphoric acid).The chemical structure of the resulting sPBI-SF was confirmed by FTIR and ~1H-NMR.The sPBI-SFs with high molecular-weights(M_n=39400-65500)were soluble in DMF,DMSO or DMAc.Therefore,they could form some transparen...