Novel imidazole-grafted hybrid anion exchange membranes based on poly(2,6-dimethyl-1,4-phenylene oxide) for fuel cell applications

Novel organic-inorganic hybrid membranes, based on poly(2,6-dimethyl-1,4-phenylene oxide), have been prepared through 1,2-dimethylimidazole functional groups and double crosslinking agents including 3-glycidyloxypropyltrimethoxysilane and tetraethyl orthosilicate by sol-gel process for the purpose of improving the conductivity and alkaline resistance. The structure of membranes was characterized using Fourier-transform infrared spectra, H-1 NMR, and X-ray diffraction. The physico-chemical properties of all membranes were shown in ion exchange capacity, water uptake, stability, and conductivity. Membranes with OH- conductivity up to 0.022 at 25 degrees C and 0.036 S cm(-1) at 80 degrees C. Promisingly, the chemical stability of the resulting membranes remains unchanged after storage in 2 mol dm(-3) KOH at 25 degrees C over at least 10 days. The tensile strength can be higher than 30 MPa, and the elongation at break (Eb) is in the range 6.68-10.84%. Hence, this hybrid membrane can be potentially applied in alkaline fuel cells. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46034.