Abstract A new series of sulfonated polyimide (SPI) copolymers containing NH, OH, or COOH groups were synthesized by the polycondensation of 1, 4, 5, 8- naphthalnetetracarboxylic dianhydride, 3, 3′-bis (sulfopropoxy)-4, 4′-diaminobiphenyl, and 3-(4-aminophenyl)-5-(3-aminophenyl)-1H-1, 2, 4-triazole (SPI-8-m), 3, 5-bis (4- aminophenyl)-1H-1, 2, 4-triazole (SPI-8-p), 3, 6-diaminocarbazole (SPI-9), 3, 5-diamino- ...