Changes in electrical properties of polystyrene films under the influence of electrical discharges in gases

Abstract

AbstractThis paper describes changes of the following electrical properties of polystyrene films dielectrical permeability, ε, dielectrical loss, tan σ, and conductivity under the influence of electrical discharges in air and nitrogen.It is shown, that under the influence of electrical discharges there occurs an increase in conductivity and dielectrical permeability; furthermore, there appears a new range of losses, tan σ, and a shift of dipole‐elastic losses, tan σ (alphaprocess), to higher temperatures, the latter meaning an increase in the relaxation time of the kinetic fragments.The changes observed in the electrical properties are due to changes in the polymer structure resulting from simultaneously occurring processes of crosslinking degradation and oxidation of polystyrene macromolecules. These processes also lead to changes in mechanical strength and molecular weight of the polymer. The presence of oxygen strongly accelerates these proccesses that proceed on polystyrene films under the influence of electrical discharges.