| 초록 |
A new series of poly(arylene ether sulfone) copolymers having highly sulfonated fluorenyl moieties were synthesized. The copolymers were prepared by a three-step process comprising (1) a polycondensation reaction of 4,4’-difluorodiphenylsulfone(DFDPS) with 9,9’-bis(hydroxyl phenyl)fluorene(HPF), 4,4’-thiobisphenol(TBP) and 4,4’-thiobisbenzenethiol(TBBT) at various molar ratios yielding poly(arylene ether sulfide sulfone)s and (2) their subsequent oxidation to poly(arylene ether sulfone)s, and (3) finally post-sulfonation reaction. The degree of sulfonation(DS) and ion-exchange capacity(IEC) could be precisely controlled by changing the molar feed ratio of HPF. Transparent and flexible membranes were successfully obtained from NMP solutions and evaluated as proton exchange membranes. The morphology and electrochemical properties of the membranes were investigated by AFM and impedance analyzer, and compared with other sulfonated poly(arylene ether sulfone) copolymers. |
