The Polymer Society of Korea

Abstract

Polymers tethered with protogenic groups are promising candidates for proton exchange membranes. As a demand for conductivity increases from these polymers under low humidity conditions, polymers functionalized with phosphonic acid groups are receiving great attention owing to their amphoteric nature and self-dissociation ability. In the present study, we investigate the role of acid group position for phosphonated polymers in determining proton transport properties. For this, a series of stryrenic polymers substituted with phosphonic acid group at ortho or meta or para position of the ring structure were synthesized via controlled radical polymerization. It is revealed that polymers carrying phosphonic acid groups at meta position are beneficial to improve proton transport efficiency, compared with phosphonated polymers functionalized with acid group at para position (most traditional ones) upon suppressing ion clustering as well as creating long-range hydrogen bonding networks.