SiC(Al)陶瓷纤维先驱体聚铝碳硅烷的合成与表征  

SYNTHESIS AND CHARACTERIZATION OF PRECURSOR POLYALUMINOCARBOSILANE TO SiC(Al) CERAMIC FIBERS

作　　者：余煜玺[1] 李效东[1] 陈国明[1] 曹峰[1] 冯春祥[1] 

机构地区：[1]国防科技大学陶瓷纤维及其复合材料重点实验室,湖南长沙410073

出　　处：《高分子材料科学与工程》2004年第2期85-88,共4页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(59972042)

摘　　要：利用聚二甲基硅烷(PDMS)热解聚合的液相产物聚硅碳硅烷(PSCS)与乙酰丙酮铝(Al(AcAc)3)反应制备了SiC(Al)陶瓷纤维的先驱体聚铝碳硅烷(PACS)。选用PSCS为原料消除了Al(AcAc)3在合成反应过程中出现的升华现象。合成的PACS化学式为:SiC2.0H7.6O0.13Al0.018,数均分子量Mn=2265。研究反应过程发现PSCS发生裂解重排反应,Si-H键在反应中显示出巨大的活性,反应时伴随有乙酰丙酮气相副产物产生。反应机理研究表明,PACS分子量的增加是PSCS形成的Si-H键与Al(AcAc)3的配位基发生交联反应形成Si-Al键的结果。The precursor Polyaluminocarbosilane (PACS) to SiC(Al) ceramic fibers was synthesized by the reaction of Aluminum acetylacetonate (Al(AcAc)_3) with polysilacarbosilane (PSCS), which was prepared by the thermolysis and condensation of polydimethylsilane (PDMS). The sublimation of Al(AcAc)_3 could be avoided by the use of PSCS as reactant. The empirical formula of PACS is SiC_(2.0)H_(7.6)O_(0.13)Al_(0.018), the number molecular weight is 2265. When the reaction of PSCS with Al(AcAc)_3 proceeds, an enormous decrease in the number of (Si-H) bonds in PSCS is observed, at the same time, gas acetylacetonate is a by-product of the reaction based on the ligands of Al(AcAc)_3, and after the reaction about half of ligands of Al(AcAc)_3 remains in the PACS. The reaction mechanism was found to be related to the increase in the molecular weight of PACS by the cross-linking reaction of (Si-H) bonds in PSCS with Al(AcAc)_3, which leads to the production of (Si-Al) bonds.

关 键 词：先驱体 聚铝碳硅烷 陶瓷纤维 SIC Si-Al键 聚硅碳硅烷 乙酰丙酮铝 裂解 Si-H键 

分 类 号：TQ343.41[化学工程—化纤工业]