Preparation and preliminary characterization of a poly(4-vinylpyridine) complex of a water-soluble polyaniline

A polymer complex between a sulfonated water-soluble polyaniline (SPANI) and poly(4-vinylpyridine) (PVP) is formed by mixing an aqueous solution of the protonated (hydrogen chloride) form of PVP, a cationic polyelectrolyte, with an aqueous solution of SPANI. A gel-like precipitate forms which has limited solubility in many common solvents. Thus, the approach represents a possible route to the aqueous solution processing of polyaniline. The nitrogen-to-sulfur ratio of the complex indicates approximately a 1:1 stoichiometry between PVP and SPANI monomer units. The complex exhibits modest conductivity (3.3 × 10−5 S/cm) and is electroactive when immobilized on carbon or platinum electrodes. The swellability of the gel form of the complex is characterized by a solvent content of 16 grams per gram of dry material. Thermal analysis of the dry complex indicates stability to 225 °C.