含铍聚碳硅烷的合成机理研究

Synthesis reaction mechanism of polyberylliumcarbosilane

含铍SiC陶瓷纤维是一种新型的高性能SiC纤维,而优质含铍聚碳硅烷先驱体(PBCS)的合成是得到该种纤维的重要保证。以乙酰丙酮铍(Be(acac)_2)和聚碳硅烷(PCS)为原料制备得到PBCS,并对其合成机理进行了深入研究,采用PCS和石蜡分别与Be(acac)2进行对比反应,用GC-MS对反应小分子产物进行分析,确定了Be(acac)_2与PCS的成键反应实际是Be与Si—H键反应,C—H键没有参与含铍键的形成反应;根据小分子反应产物的生成途径,合理分析了PBCS的合成反应原理。

SiC ceramic fiber containing Be is a new kind of high performance fiber material,and high quality poly-berylliumcarbonsilane polymer （PBCS）is an important guarantee for this kind of fiber.In this research,Be （acac）2 and PCS were used to synthesize PBCS to study the mechanism of synthesis reaction.Results of reac-tions between Be（acac）2 withPCS,Be（acac）2 with paraffin respectively showed that the reaction between Be （acac）2 and PCS is due to the Si—H bond rather than C—H bond.Besides,according to the products,we spec-ulate the formation path of the PBCS chemical bond rationally.