SynopsisPoly(viny1 chloride) (PVC) films were effectively dehydrochlorinated by the reaction with aqueous sodium hydroxide solutions in the presence of tetrabutylammonium bromide (TBAB) or tetrabutylphosphonium bromide (TBPB). The obtained black films were doped with iodine, ferric chloride, or boron trifluoride. By doping, the electric conductivity markedly increased up to the order of S cm-I. The activation energy of the conduction was 0.36 eV. The effects of casting solvent, film thickness, and film drawing gre described. The change in IR spectrum by doping was discussed in terms of the formation of positively charged polyenes due to electron transfer from the dehydrochlorinated PVC to the dopants.