γ射线辐照聚碳硅烷先驱丝协同热交联制备高强度碳化硅纤维  

FABRICATION OF HIGH STRENGTH SiC FIBER BY PYROLYSIS OF γ-RAY IRRADIATED POLYCARBOSILANE PRECURSOR FIBER

作　　者：黎阳[1] 许云书[1] 

机构地区：[1]中国工程物理研究院核物理与化学研究所

出　　处：《硅酸盐学报》2008年第7期965-968,共4页Journal of The Chinese Ceramic Society

基　　金：中国工程物理研究院科学技术基金重大项目(2004Z0502)

摘　　要：采用γ射线在空气中辐照聚碳硅烷(polycarbosilane,PCS)先驱丝,将吸收剂量低于凝胶点剂量的PCS先驱丝在选定条件下作特殊的热交联处理,然后在惰性气氛保护下热解转化为SiC陶瓷纤维。通过红外光谱、热重分析、拉伸强度和氧含量测试研究了聚碳硅烷先驱丝的化学结构、热分解特性的变化以及烧成SiC纤维的结构与性能。结果表明:经热处理PCS的先驱丝形成了三维网络不熔不溶结构,其陶瓷产率高于未经热处理的先驱丝的陶瓷产率;经热交联处理的先驱丝所烧成的SiC纤维抗拉强度达2.3GPa,较未经热交联处理的先驱丝所制得的SiC纤维的拉伸强度大幅提高;辐照协同热交联法制备的SiC纤维的氧含量低于直接辐照不熔化法制备的SiC纤维的氧含量。Polyearbosilane （PCS） precursor fibers were irradiated by γ-ray under an air atmosphere. The fibers with an absorbed dose below the gel point dose were thermally cured by heat treatment, and then the cured PCS fibers were converted into SiC ceramic fibers in inert atmosphere at high temperature. The chemical structure and thermal decomposition characteristics of the precursor fibers were studied with infrared and thermal gravimetric analysis. The tensile strength and oxygen content of the SiC fiber were also detected. The results show that the thermally cured fibers are infusible and insoluble because of three-dimensional net structures that were formed by cross-linking. The ceramic yield of the thermally treated fiber is higher than that of the fiber without thermal treatment. The tensile strength of SiC fiber made from thermally treated precursor fiber is 2.3 GPa, which is much higher than the one without thermal treatment. The oxygen content of SiC fibers prepared by this method is lower than the irradiation curing method.

关 键 词：聚碳硅烷先驱丝 Γ射线辐照 热交联 碳化硅纤维 氧含量 拉伸强度 

分 类 号：TQ050.4[化学工程] O631.3[理学—高分子化学]