AC Electrical Properties of Epoxy/Silicon Carbide Whiskers Composites Coated with TiO 2 and Poly(divinylbenzene)

Abstract

This article deals with the alternating current electrical properties of epoxy/silicon carbide whiskers composites coated with titanium dioxide and poly(divinylbenzene). The alternating current conductivity and dielectric properties was studied as a function of frequency in the range from 100 kHz to 2 MHz, and temperature in the range from 30 to 120°C. It was found that alternating current conductivity increases with increasing temperature and frequency. Some alternating current conductivity and dielectric properties of epoxy/SiC whiskers composites coated with titanium dioxide and poly(divinylbenzene) as dielectric constants, activation energy, and relaxation time were determined. The observed enhancement in alternating current conductivity is attributed to increase in the number of conduction paths created by the whiskers contacts in the composite to give higher electrical conductivity. The universal power-law of alternating current conductivity is observed in silicon carbide whiskers composites. The calculated power exponent (less unity) is physically acceptable within this applied model.

Keywords

silicon carbide whiskers composites poly(divinylbenzene)conductivity titanium dioxide activation energy.

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