Characterization of multiblock sulfonated poly (arylene ether sulfone) as proton exchange membranes

A new series of hydrophobic-hydrophilic multiblock sulfonated poly(arylene ether ketone)-b-poly (arylene ether ketone) copolymers were successfully synthesized and evaluated for use as proton exchange membranes (PEMs). The membrane properties of block copolymers including ion exchange capacities (IECs), water uptake and proton conductivities were characterized for the multiblock copolymers and compared with random sulfonated poly(arylene ether)s and other multiblock copolymer membranes at similar ion exchange capacity value. This series of multiblock copolymers showed moderate conductivities up to 0.063 S/cm at 80 degrees C with very low water uptake of 19%. Therefore, they are considered to be promising PEM materials for fuel cells.