Electrochemical effects as the source of electromotive force in metal(1) –polymer–metal(2) systems

Abstract

It has been pointed out that the metal–polyethylene-terephthalate–metal, M1-PET-M2, systems employed in the study of thermally stimulated currents behave as primary batteries. The open-circuit voltages largely arise from the electrode reactions likely to occur at these high temperatures, especially the oxide formation on the negative electrode of this battery, although some contribution to the voltage is made by the series internal resistance of the PET itself. The open-circuit voltages, when corrected for the potential drop due to the internal resistance of the PET and other effects, correspond mainly to the electrode potentials of the metal–metal-oxide couples. This analysis is developed and verified on the basis of the recent experimental data of Ieda and co-workers on the M1-PET-M2 systems. It appears that proper attention to the appropriate electrode reactions at metals which sandwich the polymer in M1- (polymer) -M2 systems would perhaps lead to more satisfactory interpretations of the open-circuit voltages observed during investigations of thermally stimulated currents in these systems.