Conducting complexes of polyphenylene sulfides

Poly(p-phenylene) sulfide, poly(m-phenylene) sulfide, and the newly synthesized polymer poly(thio-2,8-dibenzothiophenediyl) have been treated with strong electron acceptors (AsF5, SbF5) to form conducting complexes with p-type electronic conductivities up to 3 S/cm. Near IR to UV absorption spectra and temperature-dependent conductivity measurements suggest a localization of charge carriers even at high doping levels. Elemental analysis and IR spectroscopy demonstrate that heavy exposure to AsF5 causes substantial changes in the backbone structure of these polymers. The dopant appears to predominantly induce the formation of carbon–carbon bonds bridging the sulfur linkages to form thiophene rings. This chemical modification enhances the conductivity of the complex and, in the case of poly(m-phenylene), is shown to be an actual prerequisite for achieving high conductivity.