Construction of proton transport channels on the same polymer chains by covalent crosslinking

Abstract

A series of novel crosslinked sulfonated poly(arylene ether ketone sulfone)polymers containing amino and carboxyl groups (Am-C-SPAEKS) were prepared by nucleophilic polycondensation reactions. The amino and carboxyl groups were introduced into the same polymer chains. The polymers were characterized by FT-IR and 1H NMR spectroscopy. TEM images of the polymers showed the formation of a continuous proton transport channel after the crosslinking. The proton conductivity of Am-C-SPAEKS was 0.088Scm−1, as high as that of Nafion under the same conditions. Interestingly, the amount of proton transport channels increased with increasing degree of crosslinking. However, the methanol permeability of Am-C-SPAEKS-30 membrane was 1.56×10−7cm2s−1 at 25°C, one order of magnitude lower than that of Nafion® 117 membrane.