[en] composite ; carbon black ; electrical properties
[en] The macroscopic electrical properties of carbon black filled polyethylene (PE)/poly-styrene (PS) blends depend strongly on the selective localization of carbon black particles in one of the phases of the polyblend. The electrical and dielectric properties of these materials can be understood in the framework of the double percolation theory. It appears that in the vicinity of the carbon black percolation threshold, the electrical conduction is dominated by tunneling. The recent theory of Brouers and Sarychev which includes quantum tunneling in the percolation scaling laws provides the basis for a discussion of the observed frequency dependence of the conductivity and the dielectric constant in the range 10-3 –10° Hz and its relation to the blend morphology.
Center for Education and Research on Macromolecules (CERM)