聚碳硅烷改性短切碳纤维的制备及其复合材料高温抗氧化性能研究OA

Derivative coatings of polycarbosilane are prepared on the surface of short-cut carbon fibers by chemi-cal grafting method,and boron phenolic resin composites reinforced by short-cut carbon fibers are prepared using a molding process.The basic mechanism of the chemical grafting of polycarbosilane is investigated by scanning electron microscopy and Fourier infrared spectroscopy analysis.The flexural strength of the composites after oxidation at room temperature,800 ℃,1 000℃ and 1 200 ℃,as well as the microscopic morphology and physical phase evolution of the ablation center region after oxygen-acetylene flame ablation are tested to investigate the influence of polycar-bosilane-derived coating on the high-temperature oxidation and ablation resistance of the composites.The results show that the flexural strength retention of the poly carbosilane-modified short-cut carbon fiber/phenolic numerical composites is still 12.77％after high-temperature and long-time heat treatment.And the modified short-cut carbon fiber/phenolic composites show excellent ablation resistance under the protection of polycarbosilane-derived coating.The microscopic morphology shows that a composite ceramic film is formed on the surface of the material to enhance the surface densities and protect the internal materials.