Abstract

We report the results of electrical, structural and thermal investigations on graphite/Silicone blends (G/Silicone), obtained by dispersion of graphite powder in an insulating matrix of rubber silicone. The X-ray diffraction analysis showed crystalline structure for our all studied (G/Silicone) blends. Conductivity measurements were reported in the temperature range of 298 to 423 K. The blends showed percolation behaviour. It was observed that the conductivity of these blends decreases with increasing temperature indicating a metallic behaviour. In addition to the electrical study, we have made a thermal study on these blends. We found that the thermal conductivity of these blends increases when the weight concentration (“p” %) of graphite increases. In order to give a comparative analysis of both electrical and thermal conductivity of blends, we use the Agri’s model which provides a good estimation of thermal conductivity of blends for all weight concentration. The scanning electron microscopy (SEM) analysis shows a good morphology for graphite concentration lower than 60%.

Key words: Polymer-matrix composites (PMCs), electrical properties, thermal properties, percolation.