Temperature Influence on Electrical Conductivity of PVC-TiO2 Nanocomposites

The role of the TiO2 nanoparticles on the frequency dependent electrical conductivity of PVC and on its variation with temperature is discussed in this paper. Thus, the DC and AC conductivities of PVC-TiO2 nanocomposites and unfilled PVC are analyzed from dielectric spectra of the real part of the complex conductivity and imaginary part of the complex relative permittivity, over a frequency range of 10
^-2
-10
⁶
Hz, and for temperatures from 310 to 340 K. The results obtained show significant lower conductivity values in PVC-TiO2 nanocomposites with respect to those for PVC, and consequently a significant improvement of electrical insulation performances in nanocomposite as compared to the unfilled PVC, for all the tested temperatures. The increase of the temperature leads to higher DC conductivity in both unfilled PVC and nanocomposite, showing that the electrical conduction is a thermally activated process in these materials. The activation energies for the thermally activated DC conduction in PVC-TiO2 nanocomposites and in PVC were obtained from Arrhenius plots.