Thermal degradation of phenolics and their carbon fiber derived composites: A feasible protocol to assess the heat capacity as a function of temperature through the use of common DSC and TGA analysis

Carbon/Phenolic Composites (CPCs) are among most important Thermal Protection System (TPS) materials. In addition to the challenges related to the manufacturing issues - partially covered in this paper - the possibility to properly characterize the thermo-physical and thermo-mechanical properties of CPCs is extremely important. These data are not only used to size the TPS of a space vehicle or the nozzle components of a Solid Rocket Motor (SRM) but they are also essential to model the response of a CPC in a given hyperthermal environment. However, most of the papers reporting the thermo-physical and thermo-mechanical properties of CPCs are based on very old testing facilities and, in many cases, special equipments have been developed ad-hoc. As a result, the aim of this paper was to identify a feasible approach able to assess the heat capacity as a function of temperature (up to 550 °C) of CPCs through the use of common DSC and TGA analysis, taking into account all the degradation steps of the polymeric matrix undergoing charring. The possibility to evaluate the heat of decomposition of high char yield matrices through the introduced protocols was also discussed.