Mechanical and thermal properties of microchannel insulating foams comprising a multifunctional epoxy/polyhedral oligomeric silsesquioxane nanocomposite

Abstract Polymer matrix composites are well suited for applications in space environments due to their excellent specific strengths and moduli, thermal properties, and tailorability. In efforts to further improve their performance, additives based on functionalized polyhedral oligomeric silsesquioxanes (POSS) have been successfully shown to increase long‐term durability by improving Atomic Oxygen (AO) and UV radiation resistance, as well as enhance both the thermal and mechanical properties of the polymer‐based structure. In the present work, an epoxy‐functionalized POSS has been used as a low‐percentage additive in the epoxy matrix structure of microchannel foams, resulting in improved mechanical properties and thermal stability without significantly increasing the resin viscosity, final bulk density, or thermal conductivity of the final foam structures. These nanocomposite POSS resins are also expected to display increased AO and UV longevity in space applications, allowing these multifunctional materials to not only achieve high‐performance capabilities but also be economically suitable for devices used in space environments.