Structural and low frequency dielectric studies of conducting polymer nanocomposites

Abstract

The intrinsically conducting polymer (ICP), polyaniline (PANI) has been synthesized by chemical polymerization process with the help of water soluble support polymer poly (vinyl pyrrolidone) (PVP). The X-ray diffraction of synthesized PANI-PVP polymer reveals that the polymeric nanocomposites are partially crystalline with orthorhombic phase at room temperature. The morphology of these composite polymers has been studied by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). The dielectric measurement of the sample is performed in the frequency range 100 Hz - 1MHz and temperature range 213-313 K. An analysis of real and imaginary parts of dielectric permittivity and the electric modulus indicate the polydispersive nature of relaxation time as confirmed by Cole-Cole plot of the complex permittivity. The frequency dependence of modulus spectra is found to obey an Arrhenius law with activation energy of 0.07 eV. The frequency dependent electrical data has been analyzed in the framework of the conductivity, These results elucidate that there is an increased coupling among the local dipolar motions (short range order localized motion).