Gamma radiation-induced graft copolymerization of styrene onto polyethyleneterephthalate films: Application in fuel cell technology as a proton exchange membrane

摘要

Polyethyleneterephthalate (PET) based proton exchange membrane for using in fuel cells was successfully prepared by gamma radiation-induced graft copolymerization of styrene monomer onto PET film and the consequent selective sulfonation of the grafting chain in the film state using chlorosulfonic acid (ClSO_3H). The effects of grafting conditions (e.g., monomer concentration, irradiation dose) on the degree of grafting and sulfonation condition (e.g., optimum concentration of ClSO_3H) on the degree of sulfonation were studied. The degree of grafting, the degree of sulfonation and the physico-chemical properties (such as, water uptake, mechanical strength, thermal durability, hydrolytic stability, oxidative stability) of the gamma radiation-induced grafted membrane were found to be better when compared to those of the UV-radiation grafted membrane. The membrane shows higher ion exchange capacity (0.9 mmol g~(-1)) and higher proton conductivity (0.075 S cm~(-1)), similar to those of Nafion membrane.