| A series of perfluorosulfonated proton exchange membranes with various ion exchange capacity (IEC) were prepared via solution-casting method under various casting temperature. The water uptake, swelling ratio, density, proton conductivity and methanol permeability of resulting proton exchange membranes was tested. It can be concluded that water uptake, swelling ratio, proton conductivity, methanol permeability of perfluorosulfonated proton exchange membrane will increase with increasing IEC; water uptake, swelling ratio, proton conductivity, methanol permeability of proton exchange membrane will decrease with increasing casting temperature. Tensile strength will also increase with increasing casting temperature. Tensile strength and selectivity reaches peak value when IEC is 0.91 and manufactured at 200oC. It revealed that IEC and casting temperature both influence the micro and macro performance of perfluorosulfonated proton exchange membrane. Low IEC and high casting temperature prone to form dense C-F matrix and more perfect crystal; however, hydrophilic ion clusters shrunk under such condition.PWA/silica/PFSA composite proton exchange membrane was prepared by sol-gel method in order to introduce PWA and silica into proton exchange membrane matrix. Water uptake, swelling ratio, proton conductivity and methanol permeability of the resulting composite membranes were tested. It is found that, with increasing inorganic additive, water uptake, swelling ratio, proton conductivity of composite membranes also increased, 20-40% higher than Nafion? membrane. As to methanol permeability of the composite membranes, first reduce with increasing additive amount, when additive amount was larger than 5%, methanol permeability will increase with increasing additive amount. It can be concluded that the additive has influenced the structure of perfluorosulfonated membranes. Selectivity reaches peak value when additive is 7.5%, 40-50% higher than Nafion?membrane.
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