Side chain liquid crystalline polypyrrole. Part I: Synthesis and characterization

Abstract

A new class of side chain liquid crystalline polymers containing a polypyrrole main chain has been synthesized. These materials were shown to be promising because they combine orientational behaviour and useful electrical properties. Two chemical processes of polymerization were carried out using ferric chloride or iodine as oxidizing agent. All the polypyrroles obtained exhibited smectic A phases. Polymerization in solution was achieved by ferric chloride in an organic solution containing an additional naphthalenesulphonate dopant; the conditions of polymerization were adjusted in order to obtain melt processible and mesomorphic polymers. Polymerization with iodine was performed in bulk, allowing the reaction to be effected on the oriented mesophase of the monomer. Room temperature conductivities of the polypyrrole synthesized by either process reached about 10⁻²-10⁻⁴S cm⁻¹.