Spectroscopic investigations and electrical properties of PVA/PVP blend filled with different concentrations of nickel chloride

Films of PVA/PVP blend (50/50) filled with different concentrations of NiCl2 were prepared by casting method. The prepared films were investigated by different techniques. XRD scans demonstrated that the peak intensity at 20 approximate to 20 degrees decreased and the band width increased with increase in the concentrations of NiCl2 content, which implied decrease in the degree of crystallization and hence causes increase in the amorphous region. UV-vis analysis revealed that the values of the optical band gap are affected with increase in NiCl2 content. This indicates the formation of charge transfer complexes between the polymer blend and the filler. The rise of conductivity is significant with increased concentration of NiCl2 filler; this reveals an increase in degree of amorphosity. AC conductivity (sigma(ac)) behavior of all the prepared films was investigated over the frequency range 42 Hz-5 MHz and under different isothermal stabilization in the temperature range 313-393 K. It suggests that the hopping mechanism might be playing an important role in the conduction process in high frequency region. The dielectric behavior was analyzed using dielectric permittivity (epsilon', epsilon '') dielectric loss tangent (tan delta) and electric modulus (M ''). The decrease in dielectric permittivity was observed with increase in the concentration of NiCl2 filler. This suggests the role of NiCl2 as filler to improve the electrical conductivity of PVA/PVP blend. (C) 2010 Elsevier B.V. All rights reserved.