Oxidation and ablation behaviors of carbon fiber/phenolic resin composites modified with borosilicate glass and polycarbosilane interface

In this work, modified carbon fiber-reinforced phenolic resin composites (CPR) were prepared. To improve the high temperature performance of CPR, borosilicate glass with different concentrations was incorporated and polycarbosilane (PCS) was added as an interface layer. The oxidation and ablation behaviors of the modified CPR composites were studied. It was found that the borosilicate glass filler changed the oxidation mechanism of composites at temperatures higher than 1000 degrees C, and caused the volatilization of borosilicate glass in addition to the oxidation of carbon. The strength of composites after oxidation was significantly improved via this modification. The thermal conductivities of composites decreased with the increase in content of fillers, leading to low back temperature during the ablation process and high heat-shielding performance. The ablation properties were improved via the formation of SiC with high melting point. The above results indicate that these modified composites are promising materials for application in thermal protection systems. (C) 2020 Elsevier B.V. All rights reserved.