Synthesis and properties of sulfonated poly(arylene ether ketone sulfone) copolymer

Abstract

A series of novel sulfonated poly(arylene ether ketone sulfone)s copolymer (SPAEKS- x) were synthesized by polycondensation reaction of commercial 2,2-bis(4-hydroxyphenyl)propane, 4,4′-dichlorodiphenylsulfone, 4,4′-dihydroxydiphenylether, and 3,3′disulfonate-4,4′-difluorobenzophenone. The degree of sulfonation was realized by controlling quantities of the sulfonated monomer. The structure of SPAEKS- x was confirmed by proton nuclear magnetic resonance and Fourier transform infrared instrument. The tough, flexible, and transparent films of SPAEKS- x were obtained by solution casting. These membranes with desired ion-exchange capacity (IEC) values showed good thermal stability and mechanical properties. The proton conductivity of SPAEKS- x with the IEC of 1.44 meq. g−1 is very close to that of Nafion 117 in a temperature range from 20°C to 100°C. SPAEKS- x copolymers, which combine the advantages of the sufficiently high proton transport conductivity and enhanced physical properties, will be the potential alternative materials to Nafion for proton exchange membrane fuel cell.