Thermal shield – Different fillers and their effect on rheological behavior and internal structure

Abstract. The use of polymer composite materials in aerospace as heat protection systems has been a common practice for many years. Protecting structures against extreme temperatures are crucial here. These materials must withstand temperatures of up to 3000 °C and particle-loaded flows. These materials are also called thermal shields and are, for example, complex mixtures of a polymer matrix, fibers and particles. The difficulties of such complex heterogeneous mixtures include production and processing. In cooperation with the Ludwig Maximilian University Munich (LMU), Bayern-Chemie (BC) has conducted extensive research on a thermal shield and analogue systems. A special focus was on the influence of the fillers on the internal structure. In order to examine these connections in more detail, the thermal shield and different simplified compositions were examined and compared by means of rheological oscillation measurements. Fiber mixtures have different internal structures compared to particle mixtures. These characteristics have different effects on the structure and influence the thermal shield accordingly in different ways in its rheological behavior.