由含的复合物催化活烯聚合的综合特异性活烯聚合,具有含的氧胺酸联体
Makoto Mitani1, Rieko Furuyama, Jun-ichi Mohri
1R & D Center, Mitsui Chemicals, Inc., 580-32 Nagaura, Sodegaura, Chiba, 299-0265, Japan.
Journal of the American Chemical Society
|April 3, 2003
概括
新的催化剂与含的连接物使得在室温下活体和立体特异性烯聚合. 这些催化剂产生高度协同作用的聚烯,由链末机制和位点逆转控制.
科学领域:
- 聚合物化学 聚合物化学
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
背景情况:
- 烯聚合对于生产多聚烯至关重要.
- 在室温下实现生活和立体特异性聚合仍然是一个挑战.
- 复合物与氧胺配体在烯酸聚合物中表现有前途.
研究的目的:
- 为了研究复合物的烯聚合行为与含的氧胺联体.
- 了解生活和立体特异性聚合的背后机制.
- 探索连接体结构对催化性能的影响.
主要方法:
- 合成和表征复合物与含的氧胺联体.
- 使用甲基氧 (MAO) 作为辅助催化剂的烯聚合实验.
- 密度函数理论 (DFT) 计算以阐明反应机制.
- (13)C核磁共振 ((13) C NMR) 光谱法用于确定聚合物微观结构和立体化学.
主要成果:
- 复合物催化了在室温及以上的活体和立体特异性烯聚合.
- DFT的计算表明和β-之间有着有吸引力的相互作用,促进室温生物聚合.
- 生产的聚乙烯具有高度的协同毒性,由链末控制机制和独家1,2-插入,然后是2,1-插入来控制.
- 在生产的聚烯中观察到区域块结构.
- 连接体替代显著影响了催化行为,体体质量对氧氧的整形对高协同选择性至关重要.
- 一个具有三甲基基的特定复合物产生了高度协同作用的,几乎单分散的聚烯,具有高点.
结论:
- 含的氧胺复合物是室温生活和立体特异性聚合物的有效催化剂.
- 观察到的立体特异性和生物性归因于连接体设计和位点逆转机制的组合.
- 连接物修饰,特别是固态因子,为生产先进的聚烯提供了一条微调催化剂性能的途径.
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