Study of pre-localized graphite/polyvinyl chloride electroconductive composites for sensors

Electroconductive composites were prepared by compression moulding of graphite‐coated polyvinyl chloride (PVC) below and above the glass transition temperature (Tg). Compaction below Tg shows notable effect on percolation concentration and room temperature resistivity. The resistivity as a function of composition and temperature has been studied. For higher compositions zero temperature coefficient of resistivity (ZTCR) is observed. The results of electron microscopy studies indicate that graphite is distributed between the interparticle spaces of PVC resin, forming a network of graphite channels. The thickness of channels increases with the increase of graphite content. The methods of preparation along with the processing parameters significantly affect the resistivity of the composites. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)