ABSTRACT

Polyaniline (PANI) has emerged as an important conducting polymer because of its good environmental stability, low cost, and high conductivity upon doping with acid. The methods proposed to synthesize water-soluble conducting polyaniline involved either the attachment of water-soluble functional groups to its benzene rings or the replacement of in the N–H groups of PANI by water-soluble functional groups. Through a variant of the latter method, an N-substituted water-soluble self-doped PANI, poly-(aniline-co-propanesulfonic acid aniline) [PAPSAH], was synthesized by reacting the emeraldine base first with NaH and subsequently with propane sultone. The PAMPANI solution was concentrated in a vacuum evaporator, and a film was obtained by casting from solution. PAPSAH could be cast into free-standing films directly from its aqueous solution and provided a conductivity of about 10−2 S/cm without external doping.