Surface-charged polyacrylonitrile/poly(vinyl alcohol) (PAN/PVA) colloids used to prepare proton conducting materials

Abstract

Proton exchange membranes exhibiting a well-organized structure were successfully prepared by a novel self-assembling technique using surface-charged latex nanoparticles as building blocks. The nanoparticles were synthesized in water by free-radical copolymerization. Free-standing membranes were obtained by casting the polymer emulsions followed by a cross-linking reaction. The acquired membrane exhibited a high proton conductivity of 0.04 S cm-1 with an ion exchange capacity (IEC) as low as 0.48 mmol g-1. The enhanced proton conductivity is thought to be derived from the formation of a co-continuous ionic network for ion channels by the closely packed surface-charged latex nanoparticles, facilitating proton transportation in the membranes.

Keywords

• polyacrylonitrile
• poly(vinyl alcohol)
• proton conductivity
• ion exchange capacity
• fuel cell