WEB Graphite filled thermoplastics for thermally conductive pipesWednesday (01.01.2020) 00:00 - 00:15 Part of:
Aim of an ongoing research project at ZBT is the development of an extrusion process and a thermoplastic-graphite-compound for the production of a plastic pipe with an increased thermal conductivity in the range of 2 - 5 W/mK (in radial direction) and the standardized strength requirements for pipes made of PE and PP. The product dimensions of the pipe to be developed should meet nominal diameters from DN25 to DN32 with an internal pressure resistance of PN6 (6 bar). The choice of this dimension, which is customary in the industry, guarantees a broad industrial applicability of the project results and ensures the basis for further development to other product dimensions. The particle orientation of flacky graphite in an extruded pipe is to be influenced by an innovative extrusion tool in order to achieve a high thermal conductivity with the lowest possible filler content and thus to achieve the required strength and bending stiffness. By orienting the filler particles in the heat-conducting direction (through the tube wall), the required filler content is significantly reduced and the now higher polymer content ensures sufficient mechanical strength and deformability of the tube. On the one hand, applications such as heat exchangers can thus be opened up that were previously reserved for metallic materials, and on the other hand, the efficiency of pure polymer heat exchangers already in use can be significantly improved. Increased potential lies in the area of applications in which heat transfer functions from liquid to liquid media are necessary and high corrosion resistance is required.