Chemical interactions at polymer interfaces: poly(p-xylylene-α-tetrahydrothiophene-bromide, chloride) on indium–tin-oxide

Chemical interactions, at the interface between a precursor polymer for poly(p-phenylenevinylene), namely poly(p-xylylene-α-tetrahydrothiophene-chloride), and an indium–tin-oxide transparent electrode, are identified using X-ray photoelectron spectroscopy. The HCl eliminated in the conversion process interacts with the surface of the indium–tin-oxide substrate leading to the formation of indium chloride which then diffuses into the polymer. It appears that indium–tin-oxide, or possibly the indium chloride generated at the interface, acts as a catalyst for the thermal elimination reaction. The results show unequivocally that interfacial interactions are of major importance in understanding, and ultimately improving, the performance of polymer-based electro-luminescent devices.