Preparation of sulfonated crosslinked poly(2,6‐dimethyl‐1,4‐phenylene oxide) membranes for direct methanol fuel cells by using electron beam irradiation

Sulfonated crosslinked poly(2,6-dimethyl-1,4-phenlylene oxide) (PPO) were successfully fabricated via electron beam irradiation followed by sulfonation and evaluated for direct methanol fuel cell (DMFC) applications. The thermal and mechanical properties were improved by the formation of crosslinked networks in the PPO membranes. The sulfonated crosslinked PPO (CPPO) membranes exhibited better ion exchange capacity and proton conductivity than the Nafion 115. The methanol permeability of the sulfonated CPPO membranes was effectively reduced without sacrificing other properties. Thus, these membranes could be used as a new proton exchange membrane for DMFC applications.