English Abstract
PTC Characteristic and Percolation of Conductor-Filled Polymers
Toshitaka Ota
Nagoya Institute of Technology, Ceramics Research Laboratory,Nagoya,Japan
Nippon Gomu Kyokaishi,(2004),77(
2), 48-53 General Review in Japanese.

The electrical conductivity and the PTC (positive temperature coefficient of resistivity) characteristic of conductor-filled polymers are reviewed. In order to interpret the electrical conductivity (resistivity) as a function of the volume fraction for binary composites, percolation and effective media theories, and a genaral effective media (GEM) equation which combines most aspects of both percolation and effective media theories, are introduced, and compared with experimental data of some composites such as phenol resin/copper and silicone rubber/copper. In addition, models based on the packing behavior of the filler and polymer particles are presented to predict critical volume fractions for conduction in conductor-filled polymers, where the electrical resistivity suddenly decreases.

Thermistor, PTC, Percolation, Resistivity, Composite