聚钽碳硅烷陶瓷先驱体的制备与表征

Synthesis and Characterization of Polytantalocarbosilane Precursor

为了提高SiC陶瓷纤维的综合性能,利用聚二甲基硅烷热解制得的产物液态聚硅烷(LPS)与五氯化钽(TaCl5)反应,制得含钽SiC陶瓷纤维的先驱体聚钽碳硅烷(PTCS)。研究表明,反应过程中存在LPS的裂解重排反应,Si—H键在反应中显示出很高的活性,PTCS摩尔质量的增加是LPS形成的Si-H键与TaCl5发生交联反应的结果,用LPS与TaCl5为原料不但能够使钽元素成功地引入到先驱体中并分布均匀,而且由于其成本比其它原料相对低廉,便于大批量合成。

In order to improve the properties of SiC ceramic fibers,SiC（Ta） ceramic fibers precursor of Polytantalocarbosilane（PTCS） was synthesized by the reaction of tantalum（v） chloride（TaCl5） with Liquid Polysilane（LPS）,which was prepared by the thermolysis and condensation of polydimethylsilane（PDMS）.When the reaction between LPS with TaCl5 proceeded,an enormous decrease in the number of Si-H bonds in LPS was observed.The tests reflected that the increase of the molecular weight of PTCS was related to the crosslinking reaction of the active Si-H bonds with TaCl5.As a result,Ta was successfully introduced into the precursor and distributed uniformly.And because of the low cost of the raw materials,the precursor can be synthesized in large quantities.