Preparation of graft-type polymer electrolyte membranes consisting of aromatic hydrocarbon polymer/inorganic nanoparticle composites and their properties

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

The development of polymer electrolyte membranes (PEMs) with high proton conductivity at low relative humidity (RH) and excellent mechanical properties at high RH were required for commercialization of fuel cells. 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). On the other hand, polymer membranes are reinforced mechanically by the hybridization with inorganic nanoparticles. Therefore we investigated the radiation-induced graft polymerization of ethyl p-styrenesulfonate onto hybrid films consisting of PEEK and inorganic nanoparticles such as silica, magnesium oxide and aluminum oxide, and the effects of inorganic nanoparticles on the proton conductivity and durability of the obtained graft-type hybrid-PEEK PEMs.