Relative permittivity of the dielectric composite with small doping of conductive nanoparticles

Abstract

We find and investigate the effect of an anomalous increase in the relative dielectric permittivity of a model composite dielectric consisting of a binder (paraffin) and a filler (100 nm particles of technical carbon). It is shown that the relative dielectric permittivity increases by more than 5 times compared with the estimated value for the mixture. The model was developed on the basis of the tendency of the conducting carbon nanoparticles to aggregate into electric dipoles preserving the anomalously large permittivity of the composite. It is shown that the effect depends on the preparation technology. If the melt solidification occurs under ultrasound vibrations the effect decreases by a factor of 3. The proposed model can be successfully used to develop space oriented composites because they should have enhanced conductivity combined with the low relative dielectric permittivity.