Synthesis and evaluation of graft-type polymer electrolyte membranes consisting of aromatic hydrocarbon polymer/inorganic nanoparticle composites

Fukasawa, Hideyuki*; Hasegawa, Shin; Maekawa, Yasunari

We previously reported the successful preparation of highly conducting and mechanically stable graft-type PEMs based on an aromatic hydrocarbon polymer, poly(ether ether ketone) (PEEK). Since polymer membranes are mechanically reinforced by the hybridization with inorganic particles, we synthesized graft-type hybrid-PEEK PEMs by the radiation-induced graft polymerization of ethyl p-styrenesulfonate onto the hybrid films consisting of PEEK and inorganic nanoparticles such as silica. The hybrid PEEK PEMs with 3% silica nano-particles showed higher tensile strength than the original PEEK PEMs at high temperature and high relative humidity (80C, 100%RH). This is because the filler effect of silica nano-particles and high crystallinity in the PEEK-PEMs are the origin of high tensile strength at humidified conditions.