Multiblock copolymers based on poly(p-phenylene)-co-poly(arylene ether sulfone ketone) with sulfonated multiphenyl pendant groups for polymer electrolyte fuel cell (PEMFC) application

The sPPm-b-PAES-x membranes exhibited proton conductivities comparable to or better than that of Nafion 212 in the hydrated state. The sPPm-b-PAES-16.6 and the sPPm-b-PAES-22 membranes showed outstanding PEM fuel cell performance at 80 °C under conditions of 100% relative humidity. In particular, the sPPm-b-PAES-22 membranes exhibited very high current density (∼1800 mA/cm2 at 0.6 V). Among the synthesized polymers, sPPm-b-PAES-16.6 showed reasonable dimensional change and well-developed nanoscale phase separation morphology; the proton conductivity and cell performance were comparable to those of Nafion 212, with a promising maximum power density of 0.8 W/cm2.