| 초록 |
Poly[(2,2’-(p-phenylene)-5,5’-bibenzimidazole)-co-(2,2’-(4,4’-oxybis(4,1-phenylene))-5,5’-bibenzimidazole)]s (poPBIs) were obtained by copolymerization of 4,4’-dicarboxyphenyl ether (DCPE) and terephthalic acid with 3,3’-diaminobenzidine in poly(phosphoric acid) at 240 ℃. We varied the feed ratio of DCPE from 0 to 100 mol% to study the effect of aryl ether linkages on physical and electrochemical properties of polybenzimidazoles systematically. poPBIs having larger content of aryl ether containing units showed increased solubility behavior and decreased crystallinity, which was confirmed with decreased intensity of peak around 25˚ by WAXS measurements. The proton conductivities of poPBI10 and poPBI30 containing 10 and 30 mol% of aryl ether linkages, respectively, were higher than that of poPBI0, the homopolymer which doesn’t have any aryl ether linkage. Particularly, poPBI30 exhibited high proton conductivity of 0.098 S cm-1 at the doping level of 6.69 mol H3PO4 at 180 ℃. |
