Thermal protection materials based on epoxy‐containing and phenyl‐containing polyhedral oligomeric silsesquioxane modified phenolic resin and phenolic resin/carbon fiber composites

Abstract Epoxy‐containing and phenyl‐containing polyhedral oligomeric silsesquioxane (EP‐POSS) and EP‐POSS modified phenolic resin (PR) was prepared, and its mechanical, thermodynamic and ablative properties were characterized. The results show that EP‐POSS can effectively improve the mechanical properties, thermal stability and ablative performance of PR. In the process of ablative, EP‐POSS decomposition forms a protective layer of silica, which covers the surface of the material, slows down the erosion of the internal material by high temperature heat flow, and effectively reduces the ablative rate of the material. EP‐POSS modified PR/CF (carbon fiber) composite was prepared and its ablative performance was studied. The results show that the modified material has excellent ablative resistance, and its linear ablative rate is close to 0.