THERMAL-PROPERTIES OF POLYMER/PARTICLE COMPOSITES AT LOW-TEMPERATURES

With different models, the thermal conductivity of composite materials is calculated on the basis of the thermal conductivity of the matrix and filler, of the volume fraction and shape of the fillers and with consideration of the thermal boundary resistance in the temperature range below 20 K. Measurements of the thermal conductivity and specific heat of epoxy resins with different fillers (needle-shape Ag, HTSC powders) in the temperature range 2-80 K are presented. Comparison of the measured and calculated thermal conductivity of these composites shows that above 20 K, the thermal conductivity is determined to a high degree, by the shape of the fillers.