A kind of quaternary ammonium polysulfone (PSF-BA) containing an aldehyde group on the side chain was obtained by the reaction of CPSF and 4-(imidazole-1-yl) benzaldehyde based on the preparation of chloromethylated polysulfone (CPSF). Subsequently

cross-linked polysulfone/poly(vinyl alcohol) anion exchange membrane (PSF-VA) was fabricated by the reaction of PSF-BA with polyvinyl alcohol (PVA). The chemical structure of modified polymer was characterized by infrared spectroscopy (FT-IR)

and water uptaking (WU)

size stability and alkali resistance were explored. PSF-VA composite AEMs keep excellent dimensional stability

alkali resistance and mechanical properties under high water absorption. The water absorption of PSF-AC-3 AEM (IEC is 1.47 mmol/g) at 25 and 85 ℃ is 29.9% and 47.6%

the hydrogen ion conductivity is 0.041 and 0.090 S/cm

but the swelling ratio is only 13.7% and 36.8%. The properties are even better than those of Nafion115 membrane under the same conditions. The PSF-AC AEM keeps good dimensional stability and alkali resistance at high conductivity

and the retention of ion conductivity is up to 84.7% after being soaked in strong alkali for 30 days

overcoming the problems of poor dimensional stability and alkali resistance of AEM under high ionic conductivity.