Preparation and Characterization of the Polyvinylidene Fluoride-Sulfonated Polystyrene Proton Exchange Membrane

A novel proton exchange membrane named as PVDF-SPS,was obtained by the thermally induced polymerization and phase transformation technique.The PVDF-SPS membrane was characterized using X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(ESEM) analysis and Fourier transform infrared spectroscopy(FT-IR) measurements.The water uptake,the proton conductivity and the methanol permeability of the proton membrane were measured.The PVDF-SPS membrane with the high proton conductivity and low methanol permeability has a stronger hydrophilic character than the pristine PVDF membrane and the polyvinylidene fluoride-polystyrene composite membrane(PVDF-PS),which is caused by the incorporation of sulfonic acid groups.The proton conductivity and the methanol permeability of the PVDF-SPS membrane measured at 25 ℃ is 2.93×10-2 S/cm and 8.61×10-8 cm2/s,respectively.The ratio of proton conductivity and methanol permeability of PVDF-SPS proton exchange membrane is 3.40×105 S·s/cm3,which is almost 20 times than that of Nafion-117.