| Proton exchange membrane fuel cells(PEMFC) is the most alternative fuel cell, due to their high efficiency, low environmental impact, good reliability and maintenance. As a key component of PEMFC, proton exchange membranes(PEM) is the most focus worldwide. The perfluorosulfonic acid PEM, represented by Nafion, has excellent proton conductivity, chemical stability and it is durable. However, its proton conductivity decreases obviously when operated upon 100℃because of its dehydration, and it is too expensive. Therefore, kinds of non-fluoro polymers with good thermal and mechanical stabilities can be used as PEM materials.In order to obtain PEMs with high proton conductivity upon 100℃, in this paper, sulfonated poly(phthalazinone ether ketone)s (SPPEK) with sulfonate groups were synthesized by direct polycondensation from 4-(4-hydroxyphenyl)-1(2H)- phthalazinone (DHPZ), disodium 3, 3'-disulfonate-4, 4'-difluorobenzophenone (SDFB), 4, 4'-difluorobenzophenone (DFB). Tough membranes were cast successfully from N-methyl-2-pyrrolidone (NMP) solution. Membranes in acid form were then obtained by the treatment in sulfuric acid.SPEEK/PWA composite membrane was prepared through blending method, with SPPEK as matrixThe structures and morphology of the composite membranes were characterised by FT-IR and SEM. The leakage of PWA is also tested, and it's proved that the operation requirements can be satisfied. It's seen in the TGA curves that the composite membranes are stable below 250℃. The composite membrane containing 10%wt PWA has the highest water uptake, and also exhibites the highest proton conductivity(0.0993S/cm, 94℃).SPEEK/SiO2 composite membrane was prepared through sol-gel method, with SPPEK as matrix. The structures and morphology of the composite membranes were characterised by FT-IR and SEM. It's seen in the TGA curves that the incorporation of silica improves the thermal stability of the membrane. The water uptake of the composite membranes increases with the silica content. The composite membrane containing 15%wt silica has the highest water uptake, and also exhibites the highest proton conductivity(0.0751S/cm, 94℃).SPEEK/SiO2/PWA composite membrane was prepared with SPPEK as matrix. The structures and morphology of the composite membranes were characterised by FT-IR and SEM. It's seen in the TGA curves that the incorporation of organic content didn't impact the thermal stability of the membrane. The water uptake of the composite membranes increases with the silica content while decreases with the PWA content increasing. The composite membrane containing 10%wt silica and 10%wt PWA has the highest proton conductivity(0.0751S/cm, 94℃).SPEEK/Zr(HPO4)2 composite membrane was prepared through in-situ precipitation method, with SPPEK as matrix. The structures and morphology of the composite membranes were characterised by FT-IR, SEM and XRD. The TGA curves indicate that the incroduction of Zr(HPO4)2 raises the decomposition temperature of the membrane. The proton conductivity of the composite membrane increases and higher than SPPEK membrane at high temperature. The proton conductivity of SPPEK60/Zr(HPO4)2 membrane reached 0.014S/cm at 94℃.
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