Development of proton-conductive liquid-crystalline polymer films

Abstract

A zwitterionic liquid crystal containing polymerizable moieties was designed and synthesized to develop nanostructured proton-conductive polymeric matrices. The equimolar mixture of the monomer and benzenesulfonic acid was prepared. Both of the monomer and the mixture exhibited hexagonal columnar liquid-crystalline (LC) phases. Photopolymerization of the monomer and the mixture in the LC states resulted in the formation of free-standing polymer films preserving the LC nanostructures. The photopolymerized mixture showed proton conductivities on the order of 10-7~10-5 S cm-1 between 30~150 °C, while for the polymerized zwitterionic molecule, lower proton conductivities on the order of 10-9~10-8 S cm-1 between 30~150 °C was observed.