Influence of Electro Thermal Treatment on Dielectric Properties of PP + ZrO2- Based Polymer Nanocomposites

There have been investigated dielectric properties of PP + ZrO(2)based nanocomposites after exposure to an external electric field. It is shown that beforeE = 10 center dot 10(6) kV/m the dielectric constant (epsilon'), dielectric-loss tangent (tg phi) and specific resistance (lg rho) increase but subsequent increase of electrothermal treatment (ETP) brings about the decrease of magnitude like these. It is expected that the decrease of epsilon', tg phi and lg rho of nanocompositions with the frequency rise is related to the polarization process retardation. At high-frequency values, the change of given parameters appears to be related to the destruction of hole centers and change of stationary charges in polymer near-surface layers.