摘要
将聚碳硅烷(PCS)纤维在环己烯气氛中进行化学气相交联不熔化处理,其氧含量比空气不熔化处理大大降低,组成和结构也发生了变化,气体副产物中存在环己烷和小分子硅烷．在环己烯气氛中,随着温度的升高,PCS分子的Si—H键的反应程度逐渐提高,纤维的凝胶含量逐渐增大．环己烯受热引发PCS分子中的Si—H和Si—CH3键断裂生成Si自由基和Si—CH2自由基,促进PCS分子间形成Si—CH2—Si交联结构;同时,环已烷作为侧基引入到PCS分子结构中,使纤维的碳含量随之增高．随着反应温度的升高,部分环己烷侧基和少量小分子硅烷会从PCS分子主链脱出．
Polycarbosilane （PCS） fibers cured by cyclohexene vapor had much less oxygen than those cured by air. The composition and structure of PCS fiber transformed during cyclohexene curing process, and the gaseous byproducts included cyclohexane and monosilane. Results show that reaction degree of Si-H bond and gel content of PCS fiber rapidly increase with increasing the curing temperature. The mechanism is that Si-H and Si-CH3 bonds in PCS are induced by cyclohexene to cleavage and form Si-central radicals, and the combination of these radicals accelerate the formation of a fully developed crosslinking fibers. Some cyclohexyls bond onto PCS, which makes carbon contents increase. The bonds break off with some monosilane when temperature increases.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2007年第2期177-182,共6页
Chinese Journal of Materials Research
基金
国家自然科学基金50532010资助项目
