Properties of chiral polyaniline in various oxidation states

Optically active polyaniline has been prepared as the conducting emeraldine salts PAn.(+)-HCSA and PAn.(−)-HCSA (HCSA = camphorsulphonic acid). We now report the preparation and chiroptical properties of optically active polyaniline in the following redox and pH states: leucoemeraldine base, emeraldine base, pernigraniline base and pernigraniline salt. These new chiral materials were obtained via the chemical reduction or oxidation of optically active PAn.(+)-HCSA or via de-doping with NH4OH. The reversibe generation of these novel optically active materials is of significance for potential applications.