Interface Role on Temperature Dependent Dielectric Response of LDPE-TiO2 Nanocomposites

Abstract

The temperature dependent dielectric response of the LDPE-TiO2 nanodielectric with 5wt% TiO2 nanoparticles is presented in this paper. The role played by the nanofiller-polymer interface on this dielectric response is discussed based on results obtained by dielectric spectroscopy measurements performed at temperatures between 300 and 350 K and in the frequency range $10^{-2}-10^{6}$ Hz, but also by numerical modeling and data analysis. The obtained results show that the dielectric response of the tested nanodielectric is by far more intense than the one of the unfilled LDPE. Three thermally activated relaxation processes were emphasized in nanodielectric with respect to the unfilled polymer. All these relaxations are mainly due to the dielectric response of the polymer-nanofiller interface region, which dominates the dielectric behavior of the nanodielectric.