Effect of sulfonic acid‐functionalized polysilsesquioxane on new semifluorinated sulfonated polytriazole composites and investigation of proton exchange membrane properties

Abstract

AbstractA new semifluorinated sulfonated copolytriazole is synthesized, maintaining a particular degree of sulfonation of 80% following the click reaction of two terminal azides 1,4‐bis‐[{2′‐trifluromethyl 4′‐(4″‐azidophenyl)phenoxy}]phenyl, and 4,4′‐diazido‐2,2′‐stilbenedisulfonic acid disodium salt with equal molar amounts of two dialkyne monomers namely, 1,3‐diethynylbenzene and 3,5‐bis(prop‐2‐ynyloxy)benzoic acid and designated as PTEHCSH‐80. Further, the copolytriazole is used to prepare polymer composites employing the sol‐gel reaction of the starting precursor sol 3‐(trihydroxylsilyl) propane‐1‐sulfonic acid. The weight percentage (wt%) of the filler is varied from 0 to 10 wt%, and a series of polymer composite films are prepared and abbreviated as PTEHCSH‐80/X (where X is wt% of the filler, X = 0. 2.5, 5.0, 7.5, 10.0). All the polymer composites are characterized through FTIR spectroscopic techniques. The composite films revealed various desirable properties such as high thermochemical and dimensional and mechanical stabilities in their corresponding acid form. Moreover, the composites exhibited proton conductivities ranging from 62 to 98, 117 to 182, and 131 to 195 mS/cm at three different temperatures 30°C, 80°C, and 90°C, respectively, in a hydrated state.