Impedance Spectroscopy and Dielectric Properties of Carbon Nanotube-Reinforced Epoxy Polymer Composites

Abstract

Abstract: The aim of this work is to investigate the electric properties of carbon nanotube-reinforced epoxy polymer composites, using impedance spectroscopy, in the frequency range from 1 to 10 and over the temperature range from 25 to 105 . The dielectric response was analyzed using the complex permittivity and the electrical modulus formalisms, depending on temperature and filler concentration in the polymer matrix. Furthermore, an equivalent circuit model is proposed to describe the impedance response of carbon nanotubes/epoxy composites. The impedance studies disclosed the appearance of grain and grain-boundary effects, as confirmed by the Nyquist plot. Keywords: Carbon nanotubes, Composites, Impedance spectroscopy, Equivalent circuit model, Grain effect, Grain-boundary effect.