Preparation and properties of cross-linked sulfonated poly(arylene ether sulfone)/sulfonated polyimide blend membranes for fuel cell application

A series of cSPAES/SPI blend membranes were prepared as proton exchange membrane by two types of sulfonated nonfluoropolymers: cross-linked sulfonated poly(arylene ether sulfone) (cSPAES) and sulfonated polyimide (SPI). The miscible structure of the blend membranes was confirmed by scanning electron microscopy. The water uptake, solvent uptake, water stability and swelling degree in water were tested. The results showed that, comparing with the corresponding cSPAES membranes, the stability of blend membranes in water and methanol solutions was significantly improved by the introduction of SPI. The blend membranes exhibited good thermal and mechanical properties, high proton conductivities which indicated promising potential for fuel cell applications.