Thermoforming of thermally conductive plastics with multimodal fillers

• Applicant: Professor Dr.-Ing. Christian Bonten
• Subject Area: Plastics Engineering
• Term: since 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 394247406

In thermoforming, flat semi-finished products are formed into three-dimensional components. Typically, thermoforming is used for the production of packaging articles or large-area technical components. In the production of technical components, it often competes with injection molding. The advantages of thermoforming are the ability to produce particularly large-area components, the minimum wall thickness and surface quality that can be achieved, and the low investment costs for machine and mold. However, the low investment costs for thermoforming are offset by an in-creased dependence of the component properties on the processing properties of the flat semi-finished products. The development of new materials for thermoforming can also open up previous-ly untapped application possibilities. However, as the functionalization of thermoforming materials increases, for example through the addition of additives, the complexity of the forming behavior also increases. Currently, the influence of high filler contents and different filler combinations on thermoformability and the influence of thermoforming on the resulting filler orientation and thus the thermal conductivity of the components have not yet been researched in depth. Within this research project, the use of multimodal filled thermoforming semifinished products is intended to further increase the thermal conductivity while at the same time ensuring good processability. In this way, customized thermoforming semifinished products can be developed by a clever choice of filler composition. The different filler geometries are combined and, through their interaction, positively influence the material properties. For example, the formation of heat conduction paths is favored by different particle sizes, so that smaller particles can settle between larger ones and establish additional contact. In multi-filler systems, however, other interactions can occur which need to be described in more detail. In particular, the filler interaction and its effect on forming in the thermoforming process has not yet been investigated.

• DFG Programme: Research Grants