| 초록 |
Sulfonated polyimides had been utilized and studied widely as available materials in chloro-alkali electrolysis, cationic exchange resins, proton exchange membrane fuel cell as proton conductive membrane. Sulfonated polyimide membranes have been usually prepared by introduction of sulfonated diamines to non-sulfonated dianhydrides and other non-sulfonated diamines, instead of the direct sulfonation of polyimide membranes to avoid the chemical degradation and subsequent reduction of molecular weight and mechanical properties and control the appropriate sulfonation degree and the distribution of hydrophobic and hydrophilic domain. In this study, random and block copolyimide with sulfonated diamine monomers in the polymer backbone containing carboxylic acid group were prepared by the polycondensation to observe the proton transport behavior and water vapor sorption for the different distribution of the hydrated structure connected with negative charged fixed ions. In addition, the effect of different chemical crosslinkers with or without fixed charged sulfonic acid groups on the methanol permeability was also observed in random and block copolyimide membranes in relation to the d-spacing in XRD. |
