Improvement of thermal and electrical properties of Silicone-Ni composites using magnetic field

Thermally and electrically conductive silicone rubber composites filled with nickel particles have been prepared for several filler concentrations and for three different spatial distributions using various magnetic field orientations. The alignment of metallic particles in the polymeric matrix was confirmed by SEM and optical observation of the microstructure of composites. The spatial distribution of the particles does not affect the specific heat behavior of composites; while higher heat and electric transport ability was reached for composites filled with alignment of particles along the main heat flux due to creation of 1D structure of Ni particles. This filler configuration allows enhancement of the thermal conductivity of about 100% compared to the transverse and random distribution of particles; and contributes also to reducing the percolation threshold from 25 to 2 vol.% of nickel particles. Thus a great improvement of both thermal and electrical behavior is obtained by using a magnetic field for the preparation of silicone nickel composite. (C) 2014 Elsevier Ltd. All rights reserved.