β-二酮钛配合物／MAO催化P-甲基苯乙烯间规聚合  

Syndiotactic Polymarization of p -Methyistyrene With the β-Diketonate Titanium Complex/MAO Catalyst System

作　　者：闫辉[1] 杨敏[1] 沈晓莉[1] 闫卫东[1] 

机构地区：[1]河北工业大学化工学院高分子科学与工程研究所,天津300130

出　　处：《中国材料科技与设备》2007年第1期85-87,共3页Chinese Materials Science Technology & Equipment

基　　金：国家科学自然基金资助项目（50573018）

摘　　要：本文研究了β-二酮钛配合物在MAO作用下，催化β-甲基苯乙烯间规聚合，讨论了催化剂浓度、铝钛比、反应温度对催化活性的影响，如，在催化剂浓度小于350μmol／L时，聚合活性随浓度的增加而上升，达到7．5×10^5g／molTi·h，之后迅速下降到2．5×10^5g／mol Ti·h附近上下波动，变化基本平稳。并对β-甲基苯乙烯间规聚合物进行了核磁表征。The syndiotactic polymarization ofp -methylstyrene with Ti（ dibenzoylmethanato）3 （OPh） [ （dbm）3Ti （OPh）] / methylaluminoxane （MAO） catalytic system was carried out. The presence of single sharp resonances for the respectively at 142. 8ppm, 44. 2ppm and 40. 4ppm showed that the polymer is highly syndiotactic. It revealed that electron - releasing substituents on the aromatic ring enhances the reactivity of the monomers. The changes of polymerization activity depended on the polymerization conditions, When the C（Ti） was 350μmol/1, polymerization activity was up to 7.5 × 10^5gPPMS/molTi ·h, and the Al/Ti molar ratio is 700, activity reaches the maximum value. The polymerization activity increased with the enhance of temperature from 20℃ to 120℃. But the syndiotacticity and the melting temperature decrease in the certain range. During the reaction initial course, the activity increases slightly. And after 40min, the activity remains constant, This suggests that the β- diketonate catalyst shows the stability of reaction time. The glass transition temperature （Tg） of poly（p - methylstyrene） is about 110℃. There occurs two crystalline form Ⅰ and Ⅲ, their melting temperatures （Tg） of poly（p - methylstyrene） are about 183℃ and 203℃.

关 键 词：间规聚合反应 对甲基苯乙烯 β-二酮钛配合物 活性 性质 

分 类 号：TQ316.31[化学工程—高聚物工业]