Thermoforming of thermally conductive plastics with multimodal fillers

在热成型中，平面半成品被成形成三维部件。通常，热成型用于生产包装物品或大面积技术部件。在技术部件的生产中，它经常与注射成型竞争。热成型的优点是能够生产特别大面积的部件，可以实现最小的壁厚和表面质量，并且机器和模具的投资成本低。然而，热成型的低投资成本被组件性能对平面半成品加工性能的依赖性增加所抵消。热成型新材料的开发也可以开辟以前未开发的应用可能性。然而，随着热成型材料功能化的增加，例如通过添加添加剂，成形行为的复杂性也增加了。目前，高填料含量和不同填料组合对热成型性能的影响，以及热成型对填料取向的影响，从而对组分导热性的影响还没有深入的研究。在本研究项目中，使用多模态填充热成型半成品旨在进一步提高导热性，同时确保良好的可加工性。通过这种方式，可以通过巧妙选择填料成分来开发定制的热成型半成品。不同的填充物几何形状组合在一起，通过它们的相互作用，对材料性能产生积极影响。例如，不同的颗粒尺寸有利于热传导路径的形成，因此较小的颗粒可以在较大的颗粒之间沉淀并建立额外的接触。然而，在多填料系统中，可能发生其他需要更详细描述的相互作用。特别是在热成形过程中，填料的相互作用及其对成形的影响尚未得到研究。

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.