Probing of dielectric properties of high density poly-ethylene/calcium carbonate (HDPE/CaCO3) nano-micro composite

Abstract

In this experimental investigation, high density poly-ethylene/calcium carbonate (HDPE-CaCO 3 ) micro/nano composite sheets were prepared by melt blending the master batch using twin screw extruder followed by injection molding. The dispersion characteristics were determined by field emission scanning electron microscope (FESEM) and were found to be reasonably uniform. These sheets were then subjected to electrical stresses in order to evaluate their dielectric performance. The dissipation factor (tan) and relative permittivity ( r ) were evaluated as a function of temperature in a practical range of 23 to 80°C. The composite exhibited decreased  r and tan values compared with unfilled HDPE. These results support the multi-layer model proposed in literature for nano-composite. It is also clarified that this nano-micro composite is higher in both ac breakdown strength and partial discharge resistance than for the base polymer.