Studying Thermophysical Properties of Glass Microspheres and Resultant Composite Materials

The paper examines the issues dealing with making and evaluating the properties of synthetic thermal insulation materials based on polymer matrices and glass microspheres. The aim of this study is to clarify the effect of the volume content of spherical single-shell particles on the thermophysical properties of composite materials. The thermophysical properties of a two-component system consisting of epoxy resin and glass microspheres are investigated. The volume fraction of hollow glass microspheres varies from 0 to 70%. The thermal conductivity of the composite is determined experimentally using the hot plate method. The results suggest that the thermal conductivity decreases with increasing microsphere content from 0.53 W/(m K) for pure resin to 0.4 W/(m K) for a composite with 70% volume filling. The thermal conductivity is determined and compared with theoretical predictions based on an anisotropic material model compiled using the effective medium theory approximation. The values of the thermal conductivity of microspheres and epoxy resin are calculated using the experimental graph of the change in the thermal conductivity plotted against the particle content. The results obtained can be used to design composite materials taking into account the specificity of distributed particles.