Poly(2-iodoaniline) (PIANI) and poly(aniline-co-2-iodoaniline) [P(An-co-2-IAn)] were synthesized by electrochemical methods in acetonitrile solution containing tetrabutylammonium perchlorate (TBAP) and perchloric acid (HClO4). The voltametry of the copolymer shows characteristics similar to those of conventional polyaniline (PANT), and it exhibits higher dry electrical conductivity than PIANI and lower than PANT. The observed decrease in the conductivity of the copolymer relative to PANT is attributed to the incorporation of the iodine moieties into the PANI chain. The structure and properties of these conducting films were characterized by FTIR and UV-Vis spectroscopy and by an electrochemical method (cyclic voltametry). Conductivity values, FTIR and UV-Vis spectra of the PIANI and copolymer were compared with those of PANT and the relative solubility of the PIANI and the copolymer powders was determined in various organic solvents. (C) 2003 Wiley Periodicals, Inc.