Crosslinked SPES-SPPSU membranes for high temperature PEMFCs

Highly sulfonated polyethersulfone (SPES; Ione exchange capacity = 3.2 meq/g) and polyphenylsulfone (SPPSU; ion exchange capacity = 3.2 meq/g) were synthesized. To get high thermal and chemical stability, a blend membrane was prepared by the composite of SPES and SPPSU. The SPES-SPPSU blend membrane after the annealing treatment at 180 °C was stable in water and other organic solvents, and the thermal stability was also more increased than that of pristine SPES and SPPSU polymers due to the crosslinking formation among SPES and SPPSU. The maximum conductivity of 0.12 S/cm was obtained at the temperature of 140 °C and RH 90%.

► Highly sulfonated polyethersulfone and polyphenylsulfone membrane.
► Crosslinked SPES-SPPSU membrane by annealing treatment.
► High proton conductivity for high temperature PEMFCs.