PREPARATION AND BEHAVIOR OF AMINO-CONTAINING SULFONATED POLY(ARYL ETHER KETONE SULFONE) CROSSLINKED MEMBRANES FOR PEMFC

The sulfonated poly (aryl ether ketone sulfone) copolymers bearing pendant amino groups were synthesized by nucleophilic polycondensation method in this paper. The C-Am-SPAEKS crosslinked membrane was obtained by a heating reaction at 180 degrees C. The FTIR spectrum and H-1-NMR spectrum showed that the amino group had been introduced into the SPAEKS copolymer and the amide bond between the amino and the sulfonic acid groups was formed. The results indicated that the covalent crosslinking between the amino and the sulfonic acid groups decreased the methanol permeability and the swelling ratio, improved the thermal stability and water retention capacity of the C-Am-SPAEKS crosslinked membrane. The proton conductivity of the C-Am-SPAEKS crosslinked membrane reached 0.0883 S/cm at 120 degrees C which is able to meet the requirements of proton exchange membrane fuel cells. The methanol permeability of the C-Am-SPAEKS crosslinked membrane was only 0.5 x 10(-7) cm(2)/s at 25 degrees C,which was much lower than that of SPAEKS membrane (8.9 x 10(-7) cm(2)/s) and Nafion (2 x 10(-6) cm(2)/s) under the same test conditions. All the results indicate that the C-Am-SPAEKS crosslinked membrane is promising as proton exchange membranes for middle-high temperature proton exchange membrane fuel cells applications and direct methanol fuel cells