A series of copolymers between o-toluidine (OT) and vinyl acetate (VA) was synthesized by a chemically oxidative polymerization, which was carried out by three different methods: suspension solution precipitation, emulsion and inverse emulsion copolymerizations by using iron trichloride, and ammonium persulfate as oxidant. The progress in the copolymerization, polymerization yield, structure, and properties of the resulted OT/VA copolymers were systematically characterized by solution potential/ temperature monitor, laser particle size, FTIR, UV-vis, and thermogravimetry techniques. The results show that the diameter, spectral characteristics, solubility, film formability, electrical conductivity, and thermostability of the virgin polymer particles formed exhibit a nonmonotonic dependence on the OT/VA ratio, Suggesting an occurrence of an oxidative copolymerization between OT and VA monomers. (c) 2006 Wiley Periodicals, Inc.