Eletrosynthesis and properties of self-doped polyaniline

Sulfonic acid ring-substituted aniline was polymerized electrochemically to obtain self-doped and water soluble polyaniline. The electric conductivity values of polymers derived from three isomers of aminobenzenesulfonic acid were in the order of 10−3 Scm−1 for as prepared samples, but increased to 10−1 ∼ 10−2 Scm−1 by chemical doping with Fe(III). The conductivity was unchanged by treating with alkaline solutions. These polymers were easily soluble in water and showed fairly reversible redox peak around 0.6 V (vs. SCE).