Processable forms of conductive polyaniline

A range of sulphonic acid dispersants have been used to dope polyaniline. If polyaniline is treated with dodecylbenzene sulphonic acid (DBSA) in refluxing toluene a stable dispersion is obtained which is shows a large increase in viscosity with time on heating. Paralleling this observation are related increases in conductivity (up to σ = 150 S/cm) and crystallinity for films cast from the dispersions. Similarly the PANI. DBSA complex may be successfully dispersed in various thermoplastic polymers such as SBS rubber or polymethylmethacrylate by melt mixing to give melt processable materials of high conductivity (up to σ = 10 S/cm) at low loadings of conductive material. The long term environmental stability of the new materials has also been evaluated.