Abstract 592081 Disclosed are methods of preparing a polyaniline homopolymer or copolymer comprising at least one carboxylic acid group, and homopolymers or copolymers arising therefrom, the methods comprising: preparing a solution of a polyaniline precursor having at least one aromatic amine group and at least one carboxylic acid group (eg. 2-aminobenzoic acid, 3- aminobenzoic acid or 4-aminobenzoic acid) in a solvent selected from aqueous methanesulfonic acid and optionally one or more additional polyaniline precursors (such as aniline) and oxidatively polymerising the polyaniline precursor or precursors.
