Graphene oxide grafted carbon fiber reinforced siliconborocarbonitride ceramics with enhanced thermal stability

Hierarchical structure consisting of graphene oxide (GO) grafted onto carbon fiber (CF) has been synthesized to improve the interfacial properties between the CFs and polymer matrix. The modified CFs are coated with siliconborocarbonitride (SiBCN) preceramic polymer by in situ polymerization to enhance their antioxidant and ablation properties. X-ray photoelectron spectroscopy were used to monitor the composition of the composites. Scanning electron microscopy images revealed that GO was successfully grafted onto CF (CF-g-GO) and coated with SiBCN preceramic polymer (CF-g-GO/SiBCN). Loading of SiBCN preceramic polymer on the surface of CF-g-GO increased remarkably compared to that on the surface of untreated CFs. Pyrolysis of CF-g-GO/SiBCN preceramic polymer at 1400 °C in inert atmosphere led to the formation of SiBCN ceramics with the approximate elemental composition of Si₃N₄/SiC/BN. TG results show that the thermal stability of the CF with ceramic layer has improved noticeably at high temperature.