Heat-conducting and dielectric characteristics of polyorganosiloxane composites

The article considers the actual problem of improving the physico-mechanical, thermophysical and electrical properties of polyorganosiloxane coatings. In this article, we propose a method for obtaining a multifunctional heat-resistant composition based on oligodimethylsiloxane with terminal hydroxyl groups filled with boron nitride. The curing process of oligodimethylsiloxane and the possible interaction of boron nitride with reactive resin groups are described. The structure of the manufactured composition is investigated, it is established that the filler in the form of dispersed particles touching throughout the volume is evenly distributed in the polymer matrix. The results of experimental studies of the dependence of the tensile strength on the percentage of boron nitride, indicating the hardening of the composite, are graphically presented. Studies of the strength at separation of the cured composition from the substrate (adhesion) of various materials have shown that this value increases with the introduction of boron nitride. The dependence of the thermal conductivity coefficient on the ratio of components is established. The percolation point is determined by the Monte Carlo method. The dependences of the electrical resistivity and temperature dependence on the content of boron nitride are determined. The Poisson equation is solved in MathCad and graphical results of solving the heat transfer problem for traditional and developed composites are presented. Based on the results obtained, the areas of application of the developed composites in construction are proposed.