Atieh Motaghi - Department of Chemical & Biochemical Engineering, the University of Western Ontario, London, Ontario, Canada
Ghodratollah Hashemi Motlagh - Department of Chemical Engineering, Faculty of Engineering, University of Tehran, Tehran
Andrew Hrymak - Department of Chemical & Biochemical Engineering, the University of Western Ontario London, Ontario, Canada

The aim of this study is to characterize the synergy effect of carbon black (CB) and carbon fiber (CF) on the electrical conductivity and percolation threshold of hybrid polymer composites. Different formulation of polystyrene (PS) filled with three (CF/CB) ratios of 1.67, 3.33, 6.67 was compounded through twin screw extruder and then compression molded into sheets. Through-plane and in-plane electrical conductivity were measured by methods of 2 and 4 probes. The results showed synergism when using both fillers in the composite. The hybrid composites had the higher value of electrical conductivity than the single filler composite even at the filler content lower than the percolation threshold of single filler. Standard percolation model was used to determine the percolation threshold. The percolation threshold of hybrid composite moved toward the lower content of whole filler when both CB and CF were present in the composite. The effect of average length size and distribution of CF, CB aggregation size and the morphology on percolation and electrical conductivity was considered by microscopic analysis

Polystyrene, Hybrid, Electrically Conductive, Model, Filler, Thermoplastics