| 초록 |
Engineering plastics have excellent mechanical and thermal stabilities and their sulfonated analogs are frequently used as proton conducting membrane materials. Sulfonated poly(ether ether ketone) (sPEEK) or sulfonated poly(phenylene oxide) (sPPO) is one of the examples, and a highly sulfonated membrane shows good proton conductivity, but inferior methanol permeability for its commercial application for DMFC. To decrease high fuel permeability, sPEEK or sPPO was crosslinked through sulfonic acid. The in-situ crosslinking of sulfonic acid was performed by addition of 1,1'-carbonyldiimidazole (CDI) and diamines as crosslinking agents. The sulfonic acid groups were activated by CDI and produced N-sulfonyl imidazole. Then, the activated N-sulfonyl imidazole were reacted with diamine. The crosslinking of the membranes was investigated with FT-IR. And they were characterized based on water uptake, ion exchange capacity, proton conductivity and methanol permeabilities. |
