A novel carborane–carbosilane–(cyclo-silazane) polymer has been synthesized as precursor of ceramic and applied to the surface treatment of carbon fiber (Cf) by precursor infiltration and pyrolysis method. The preparation of carborane precursor was carried out by hydrosilylation of trivinyltrimethylcyclosilazane with dimethylchlorosilane firstly, and then by polycondensation reaction with hydroxylated 1,1′-hydroxysilylene-2,2′-bis(hydroxydimethylsilyl)biscarborane whose −OH was formed by transferring the newly introduced C–H bond via hydroxylation. Chemical structure of the polymer was studied by liquid-nuclear magnetic resonance while evolution of various ceramic phases was studied by Fourier transform infrared spectroscopy and the thermal curing process was studied by thermogravimetric/differential thermal analysis and pyrolysis-gas chromatography/mass spectrometry. The cross-linked polyborosilazane precursor exhibited higher ceramic yield of 65.6% at 1000°C. The coating on the Cf was identified to be uniform, relatively smooth, and continuous with a thickness ranged from 0.1 to 0.5 μm through scanning electron microscope and energy dispersive spectroscopy. Thermogravimetric analysis revealed high temperature stability of the coated Cf in flowing air up to 600°C.

中文翻译：

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新型碳硼烷陶瓷前驱体的合成、热解及碳纤维涂层

合成了一种新型碳硼烷-碳硅烷-（环硅氮烷）聚合物作为陶瓷的前驱体，并通过前驱体渗透和热解法应用于碳纤维（Cf）的表面处理。先将三乙烯基三甲基环硅氮烷与二甲基氯硅烷进行氢化硅烷化，然后与羟基化的 1,1'-羟基亚甲硅烷基-2,2'-双（羟基二甲基甲硅烷基）双碳硼烷通过转移新引入的羟基形成-OH 缩聚反应制备碳硼烷前驱体。 C-H键通过羟基化。通过液核磁共振研究聚合物的化学结构，通过傅里叶变换红外光谱研究各种陶瓷相的演化，并通过热重/差热分析和热解-气相色谱/质谱分析研究热固化过程。交联的聚硼硅氮烷前驱体在 1000°C 下表现出更高的陶瓷产率为 65.6%。通过扫描电子显微镜和能量色散光谱发现，Cf 上的涂层均匀、相对光滑且连续，厚度范围为 0.1 至 0.5 μm。热重分析显示涂层 Cf 在高达 600°C 的流动空气中具有高温稳定性。通过扫描电子显微镜和能量色散光谱发现，Cf 上的涂层均匀、相对光滑且连续，厚度范围为 0.1 至 0.5 μm。热重分析显示涂层 Cf 在高达 600°C 的流动空气中具有高温稳定性。通过扫描电子显微镜和能量色散光谱发现，Cf 上的涂层均匀、相对光滑且连续，厚度范围为 0.1 至 0.5 μm。热重分析显示涂层 Cf 在高达 600°C 的流动空气中具有高温稳定性。