Characterization of conducting Polypyrrole filled PVC- PMMA thin film thermo electrets

Abstract

The present study reveals with study of electrical, thermal and optical band gap of polypyrrole filled PVC: PMMA thin films themoelctrets.  Conducting polymer composites have attracted considerable interest in recent years because of their numeric applications in variety of electric and electronic devices. Polypyrrole has been regarded as one of the most studied conducting polymer because of its physical and electrical properties that have led to several applications such as solid state devices and electronics. The electrical conductivity of polypyrrole filled PVC: PMMA thermoelectrets have been studied. Electret effects in polymers can be produced by orientation of dipoles and /or trapping of charge carriers injected from electrodes as well as generated   in the bulk of polymers. It has been shown by thermally stimulated discharge conductivity technique (TSDC) that the characteristics of electrets are very sensitive to the structure of electret forming materials. In this respect TSDC study of composite is likely to yield information about the extent of mixing between the components. Electrets prepared by composites have better charge storage capacity than the individual polymers. Measurements of TSD conductivity have been carried out at different polarizing fields. It has been observed that the conductivity of   polypyrrole filled PVC: PMMA   composite have been increased with increase in percentage of polypyrrole. The X-RD diffractogram reveals the amorphous nature of the films. The thermograms are plotted between logσ and temperature (103/T).From the analysis of the absorption spectra the band gap of polypyrrole filled PVC: PMMA composite have been found to be lie in the range 1.8 eV to 3.3 eV. Thermal stability of Polypyrrole filled PVC: PMMA was investigated by TGA/DSC. It is evident from the results that PPy filled polyblends are more stable