γ辐照联合热交联聚碳硅烷先驱丝热解制备高强度氮化硅陶瓷纤维  

Preparation of High Strength Silicon Nitride Ceramic Fibers From Polycarbosilane Fibers by γ-Ray Irradiation and Thermal Cross-Linking

作　　者：黎阳[1] 高家诚[2] 许云书[3] 

机构地区：[1]贵州师范大学材料与建筑工程学院,贵州贵阳550014 [2]重庆大学材料科学与工程学院,重庆400045 [3]中国工程物理研究院核物理与化学研究所,四川绵阳621900

出　　处：《核化学与放射化学》2014年第5期272-276,共5页Journal of Nuclear and Radiochemistry

基　　金：贵州省教育厅重点实验室资助项目(黔教合KY字[2012]004)

摘　　要：在空气气氛中采用γ射线辐照处理聚碳硅烷(PCS)先驱丝,辐照先驱丝经Ar中热交联、NH3中热解氨化、N2中高温氮化处理制备了氮化硅陶瓷纤维。研究了热交联处理对辐照先驱丝化学结构、凝胶含量、氨化陶瓷产率、抗拉强度、微观形貌及氧含量的影响。结果表明:热交联处理生成了Si—CH2—Si和Si—O—Si桥连结构,桥连结构使PCS先驱丝实现凝胶化;热交联处理不仅大幅提高了辐照PCS先驱丝的氨化陶瓷产率,还提高了热解所得氮化硅陶瓷纤维的抗拉强度,而且还降低了陶瓷纤维的氧含量;吸收剂量为1.0MGy的辐照丝经热交联处理后,其热解所得氮化硅陶瓷纤维抗拉强度达2.05GPa,氧质量分数仅为9.5%。Polycarbosilane （PCS）precursor fibers were irradiated byγ-ray in air.Silicon nitride ceramic fibers were obtained from the irradiated PCS fibers by process of thermal cross-linking treatment in Ar,ammoniation pyrolysis in NH3 and high temperature nitriding treatment in N2 .The effects of thermal cross-linking treatment on chemical structure,gel content,ammoniation ceramic yield,tensile strength,microstructure and oxygen content were studied.The results show that bridge structures of Si—CH2—Si and Si—O—Si are formed in the PCS fibers by thermal cross-linking treatment and make the PCS fibers become gelling.The ammoniation ceramic yield of the irradiated PCS fibers increases sharply after thermal cross-linking treatment.The tensile strength of the silicon nitride ceramic fibers＆amp;nbsp;increases sharply, while the oxygen content decreases. After thermal cross-linking treatment,the tensile strength of the silicon nitride ceramic fibers derived from the PCS fibers with absorbed dose of 1.0 MGy reaches 2.05 GPa and the oxygen mass fraction is 9.5%.

关 键 词：聚碳硅烷 γ射线 辐照 热交联处理 氮化硅陶瓷纤维 

分 类 号：O631.34[理学—高分子化学]