芴基胺基二甲基钛配合物催化的乙烯和降冰片烯及其衍生物共聚研究

Copolymerization of ethylene,norbornene and its derivatives catalyzed by fluorenylamino dimethyl titanium complex

本文以制备符合镜头用COC材料性能的光学透明高分子材料为导向,选用芴基胺基二甲基钛类配合物,研究了不同催化剂结构、助催化剂、温度以及共单体投料比等聚合条件对于乙烯与降冰片烯(NB)共聚反应的影响。采用高温GPC、DSC和NMR等表征手段对共聚反应以及共聚产物链结构进行研究。结果表明C_(s)-对称的[t-BuNSiMe_(2)Flu]TiMe_(2)(Ia)配合物在1.2当量比的Ph_(3)CB(C_(6)F_(5))_(4)的活化下共聚活性最高达到2040 kg/(mol·h),且对NB的共聚能力最强,NB的插入率在40.4%~56.7%范围内可控。所得共聚产物的玻璃化转变温度(Tg)与NB的插入率呈线性关系,可在115~175℃范围内可控。同时探究乙烯与双环戊二烯(DCPD)的共聚结果发现,Ia-Ph_(3)CB(C_(6)F_(5))_(4)体系对共聚表现出很高的活性,聚合温度为60℃时共聚合活性高达5190 kg/(mol·h),共聚物中DCPD的插入率最高达46.7%。当两种共单体的插入率相同时,乙烯/DCPD共聚物的Tg高于乙烯/NB共聚物的Tg。

This paper is oriented to the preparation of optically transparent polymer materials that meet the performance of COC materials for lenses.The effects of different catalyst structures,cocatalysts,temperatures and comonomer feed ratios on the copolymerization of ethylene and norbornene(NB)were studied by using fluorenylaminodimethyl titanium complexes.Using high temperature GPC,DSC and NMR testing and other characterization methods to study the copolymerization reaction and the chain structure of the copolymerization product,the results show that when the C_(s)-symmetric[t-BuNSiMe_(2)Flu]TiMe_(2)(Ia)complex is in the 1.2 equivalent ratio of Ph_(3)CB(C_(6)F_(5))_(4),the maximum copolymerization activity under activation reaches 2040 kg/(mol·h),and the copolymerization ability for NB is the strongest.The insertion rate of NB is controllable in the range of 40.4%~56.7%.The glass transition temperature(Tg)of the obtained copolymerization product has a linear relationship with the insertion rate of NB,which can be controlled in the range of 115~175℃.At the same time,the results of the copolymerization of ethylene and dicyclopentadiene(DCPD)found that the Ia-Ph_(3)CB(C_(6)F_(5))_(4) system showed high activity for copolymerization,and the copolymerization activity was as high as 5190 kg/(mol·h)at a polymerization temperature of 60℃.The insertion rate of DCPD in the copolymer is as high as 46.7%.When the insertion rate of the two comonomers is the same,the Tg of the ethylene/DCPD copolymer is higher than the Tg of the ethylene/NB copolymer.