Homopolymer-like sulfonated phenyl- and diphenyl-poly(arylene ether ketone)s for fuel cell applications

Two series of homopolymer-like sulfonated aromatic poly(ether ketone)s (SPEKs) were readily prepared and post-sulfonated using mild conditions. The homopolymer-like SPEKs exhibited advantages in synthesis and physical properties over typical post-sulfonated random copolymers, such as rapid and mild sulfonation conditions, high molecular weights, site specificity and control over IEC, as well as an excellent combination of dimensional swelling stability, low methanol permeability and high proton conductivity. These beneficial membrane properties are reflected in the attractive direct methanol fuel cell (DMFC) and polymer electrolyte membrane fuel cell (PEMFC) performance of these homopolymer-like SPEKs as compared with typical random copolymer SPEKs.