Synthesis and Properties of an N-Substituted Polypyrrole with Liquid Crystalline Moieties
The synthesis and characterisation of two pyrrole monomers substituted at the N-position with a liquid crystal group are reported. Polymerisation of one of these compounds produced a soluble liquid crystalline semiconducting polymer. The side-chain of the polymer had a flexible spacer of nine methylene units, terminated by a mesogenic cyanobiphenyl group. The new compounds were chemically characterised and were found by hot-stage polarised optical microscopy to exhibit liquid crystal mesophases. The polymer was lightly doped p-type by exposure to iodine vapour, and its electrical conductivity was measured. The polymer synthesis and doping/dedoping processes were also briefly studied by cyclic voltammetry.