氯铂酸催化剂在聚碳硅烷与二乙烯基苯交联中的应用  

APPLICATION OF CHLOROPLATINIC ACID AS CATALYST IN CROSS-LINKING OF POLYCARBOSILANE/ DIVINYLBENZENE

作　　者：陈曼华[1] 陈朝辉[1] 肖安[1] 

机构地区：[1]国防科技大学航天与材料学院重点实验室,长沙410073

出　　处：《硅酸盐学报》2004年第6期759-762,共4页Journal of The Chinese Ceramic Society

基　　金：国防预研资助项目。

摘　　要：为了提高聚碳硅烷与二乙烯基苯(polycarbosilane/divinylbenzene,PCS/DVB)硅氢化交联反应程度,采用改性氯铂酸催化的方法对PCS/DVB交联进行了研究。研究表明:氯铂酸催化性能与其用量、交联温度、以及PCS相对分子量有关。当固体PCS相对分子量低于1500,该反应中氯铂酸催化剂的用量为12.5×10-6,低分子量PCS中Si—H含量较高,且分子链支化程度低,易发生硅氢化反应;高分子量PCS中Si—H含量较低,且分子链自身支化程度高,活性基团被包裹于大分子链中,其Si—H键参加反应空间位阻大。氯铂酸催化剂在低温下催化作用不明显,催化交联的反应温度在150℃以上。The application of chloroplatinic acid as catalyst to enhance the reaction of hydrosilylation in cross-linking of polycarbosilane/ divinylbenzene (PCS/DVB) was investigated. Results indicate that the catalytic performance of chloroplatinic acid depends on quantity of catalyst, reaction temperature and molecular mass of PCS. When solid PCS is under 1 500 of relative molecular mass and mass fraction of chloroplatinic acid used in reaction is 12.5 ×10^(-6), there is more relative content of Si—H and less branches of molecular mass links in PCS of lower relative molecular mass than ones in PCS of higher relative molecular mass, thus the hydrosilylation in cross-linking can be easily reacted. However there is less relative content of Si—H and more branches of molecular links in higher relative molecular mass of PCS and the space resistances of reaction of Si—H are larger because active bases are wrapped in great molecular-links. Catalyzing function of chloroplatinic acid is not obvious at lower temperatures and the optimum catalyzing cross-linking temperature is above 150 ℃.

关 键 词：氯铂酸 聚碳硅烷/_-乙烯基苯 交联 硅氢化反应 

分 类 号：TQ174[化学工程—陶瓷工业] TB32[化学工程—硅酸盐工业]