Temperature dependency of impedance spectroscopy behaviors in side-chain liquid crystalline polymer

Abstract

In this paper, the electrical properties of side-chain liquid crystalline polymer (SLCP) are investigated by impedance spectroscopy technique. We report the measurement of dielectric and conductivity for SLCP from 1 kHz to 10 MHz within the temperature range from 300 to 370 K. The DC conductivity obeys Arrhenius law and it gives a small deviation at 315 K. The activation energies are equal to 0.20 eV and 0.75 eV for high and low temperatures, respectively. The frequency dependence of conductivity satisfies the power law, sigma(AC) = Aw(5), with s = 0.50-0.57. The evaluated power law exponent s exhibits nearly linear decreasing behavior with temperature. This suggests that the Correlated Barrier Hopping (CBH) model is the operating mechanism. (C) 2009 Elsevier B.V. All rights reserved.