Electrical conductivity of carbon fibres/polyester resin composites in the percolation threshold region

Abstract

The electrical conductivity of composites of a polyester resin filled with short carbon fibres has been investigated with a special attention to the properties in the percolation threshold region. A very low percolation threshold (0.7-0.8 vol.% of the filler) was confirmed. In contrast, to S-shaped curves calculated according to the percolation theory of composites of globular particles, the experimental conductivity vs. fibre content dependence, after a steep increase in the percolation region, increased almost linearly.