Electrical and dielectrical properties of the percolating system polystyrene/polypyrrole particles

Percolation is a commonly observed phenomenon in the properties of many composite materials. In two-phase materials, where the electrical conductivity of the disperse phase is significantly different than that of the host phase, the conductivity versus concentration (of the dispersed phase) shows a percolation behaviour. With the main aim of control the percolation threshold, in order to optimise the Radar electromagnetic absorption, new composite materials were prepared, based on polystyrene (PS) and polypyrrole (PPy) particles. The percolation critical concentration was controlled, changing the ratio of the size of that particles, and this will be presented in a next communication. In this paper we report the dc conductivity (σdc), with applied fields up to 100 kV m−1, and the complex permitivitty (ε′, ε′′) at low frequencies (1 mHz