THERMALLY CONDUCTIVE POLYMER COMPOSITIONS

While polymers are widely used for their excellent insulating properties there is a growing need for thermally conductive polymer compounds. The thermal conductivity of metal particle, mineral particle, and carbon fiber filled compounds are examined at volume concentrations up to the maximum packing fraction of each filler. From these data the coefficients in Nielsen's model were determined for each type of filler. Gaps in available thermal conductivity data were then predicted using these coefficients the properties of the polymer and filler and the volume concentration of the filler. Gaps were found to exist mostly for compounds containing short fiber reinforced compounds. A comparison of predicted values of thermal conductivity for such systems with the sparse data available shows that Nielsen's model cannot be applied to highly filled fiber reinforced composites because it cannot account for the anisotropy of such compositions.