Using diethylamine as crosslinking agent for getting polyepichlorohydrin-based composite membrane with high tensile strength and good chemical stability

Abstract

A composite anion exchange membrane of crosslinked quaternized polyepichlorohydrin/polytetrafluoroethylene (CQPECH/PTFE) had been prepared via a green and facile method, where diethylamine, 1-methylimidazole and PTFE, respectively, served as crosslinking agent, quaternization reagent and supporting material. The structure and morphology of CQPECH/PTFE membrane were investigated. Water uptake, swelling ratio, ionic exchange capacity, hydroxide conductivity, chemical stability, and thermal and mechanical properties were measured to evaluate its performance in a direct methanol alkaline fuel cell. The results indicated that CQPECH had penetrated into the pores of PTFE membrane, showing a dense and uniform structure without any pore and phase separation. Besides, CQPECH/PTFE membrane exhibited high ionic conductivity, considerable ionic exchange capacity, moderate water uptake and low swelling ratio. More importantly, the obtained composite membrane displayed high tensile strength and good chemical and thermal stability, suggesting the great potential application of CQPECH/PTFE membrane as anion exchange membrane. Crosslinked quaternized polyepichlorohydrin/polytetrafluoroethylene composite anion exchange membrane had been prepared via a green and facile method, where diethylamine served as crosslinking agent. With a dense and uniform structure without any pore and phase separation, the obtained composite membrane exhibited high tensile strength and good chemical stability.