A self-organized network of nanochannels enhances ion conductivity through polymer films

Graft polymers of well-defined structure consisting of monodisperse poly(sodium styrene sulfonate) graft chains and a polystyrene backbone have been synthesized by stable free radical polymerization. Proton-exchange membranes prepared from these polymers possess phase-separated nanochannels of ionic domains and exhibit larger proton conductivity compared to analogous membranes prepared from random copolymers of sodium styrene sulfonate and styrene.