Study on phenolic-resin/carbon-fiber ablation composites modified with polyhedral oligomeric silsesquioxanes

This study focuses on phenolic-resin/carbon-fiber (PR/CF) ablation composites modified with polyhedral oligomeric silsesquioxane (POSS) and tetraethoxysilicate (TEOS). Four nanomodifiers based on diglycidyl ether of biphenol A (DGEBA), TEOS-SiO₂ (T-SiO₂), octamethyl-POSS (Me-POSS) and phenyl-POSS (Ph-POSS) were prepared and employed to modify the PR/CF ablation materials. To compare ablation properties of the four modifiers, the correlation of the material structures and ablation properties are discussed with ablation tests and morphology measured by SEM. As a result, the former three is not viable as modifiers to enhance the ablation resistance; on the contrary, the properties of Ph-POSS show that it is suitable and more effective as a modifier for ablation materials.