Thermally conductive plastics: a mineral solution - Thermal management in thermoplastics and thermosets

摘要

For many years additives based on mineral resources have played an important role as fillers in the plastics sector. Special fillers give thermoplastics and thermosets better properties as regards mechanical strength, thermal properties and dielectric properties. Recently however these traditional requirements have been joined by new ones. In particular the use of electrical components with a high energy density (processors, light-emitting diodes, electric motors, and so on) depends on an efficient dissipation of the heat produced while simultaneously maintaining the electrical insulationing function of the plastic materials used. Although plastics have a very low thermal conductivity this can be increased significantly by the incorporation of additives with a high inherent thermal conductivity. The various materials which can be used for conducting heat in thermoplastics and thermo-sets are surveyed. The focus here is placed on thermal conductivity, mechanical properties, and the commercial feasibility of heat-conductive plastics. Important subject areas covered here will be the mechanisms of convection and thermal radiation necessary for heat transfer and also influencing factors such as, for example, filler content, particle size distribution and processability. A comparison is also made of the potential for weight reduction, the costs and the carbon-footprint calculation for manufacturing a heat sink made of aluminum and a heat sink made of plastic (polyamide 6-compound).