在双核d(0) 烯聚合催化过程中的近距离和合作效应. 结构和反应机制的理论分析
Alessandro Motta1, Ignazio L Fragalà, Tobin J Marks
1Dipartimento di Scienze Chimiche, Universita di Catania, and INSTM, UdR Catania, Viale A. Doria 6, 95125 Catania, Italy.
Journal of the American Chemical Society
|March 3, 2009
概括
双金属约束几何学催化剂 (CGCs) 在乙烯聚合过程中表现出独特的合作效应. 金属与金属的接近影响了催化剂的性能,导致聚乙烯的特性发生了变化,例如分支和分子重量.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物科学 聚合物科学
- 催化剂是一种催化剂.
背景情况:
- 约束几何学催化剂 (CGCs) 在烯聚合过程中至关重要.
- 双金属催化剂为新的催化性能提供了潜力.
- 了解金属对金属的近距离效应是催化剂设计的关键.
研究的目的:
- 研究双金属CGCs的合作催化特性.
- 分析金属对金属的接近对乙烯聚合物的影响.
- 阐明了聚合物微观结构中毒性相互作用的作用.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 对预催化剂几何和离子对形成的分析.
- 在olefin聚合过程中审视气体相互作用.
主要成果:
- 双核催化剂表现出增加的离子对解离能.
- 催化剂性能对催化剂组件之间的几何匹配很敏感.
- 阳性相互作用影响聚乙烯分支和分子量.
结论:
- 双金属CGC中的金属-金属相邻性驱动着独特的催化行为.
- 激烈的相互作用对观察到的连锁性质负责.
- 优化Zr-Zr近距离可以提高聚乙烯的性能.
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