The effective thermal conductivity of polymer composites filled with high conductive particles and the shell structure

Abstract

AbstractThe addition of fillers with high thermal properties to polymer matrices increases the thermal conductivity of the composites in comparison with pure polymers. In the literature, various models have been proposed for predicting the thermal conductivity of polymer composites, where, in order to agree with the experimental data, some control parameters are introduced, the physical meaning of which is sometimes in doubt. In the present paper, a new effective thermal conductivity model of polymers filled with highly conductive particles is proposed. According to this model, the structure of a polymer composite is represented as the sum of two different parts: a structure with uniformly dispersed in polymer and not in contact with each other filler particles, and a structure with randomly distributed polymer particles, completely covered by monolayers of aggregated filler particles (“shell structure”). The comparison shows good agreement between the results of the proposed model and experimental data, in contrast to the results of the Lichtenecker and Mamunya models. Based on the proposed model, the aggregation abilities of filler particles for some polymer composites have been determined.