烯聚合催化中的结构-活性关系:是关键吗?
Gianluca Ciancaleoni1, Natascia Fraldi, Peter H M Budzelaar
1Dipartimento di Chimica, Università di Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy.
Journal of the American Chemical Society
|September 16, 2010
概括
使用特定催化剂的烯聚合显示出缓慢的传播速率,主要是由于. 这项研究揭示了催化剂设计与管理聚合物聚合的单体捕获过程中的损失之间的关键联系.
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
- 计算化学是一种计算化学.
背景情况:
- 双 (氧胺) 催化剂用于烯聚合.
- 甲基氨酸 (MAO) 是一种常见的联合催化剂.
研究的目的:
- 通过使用含有MAO的bis(phenoxyamine) Zr-dibenzyl催化剂来研究烯聚合的激活参数.
- 为了确定在这个系统中限制链传播速率的因素.
- 探索催化剂行为和单体捕获过程中的损失之间的关系.
主要方法:
- 激活参数的实验测量.
- 密度函数理论 (DFT) 的计算.
- 对烯聚合催化剂的文献综述.
主要成果:
- 实验和DFT计算始终确定了热量为低链传播速率的主要贡献者.
- 传播速率和催化剂在捕获单体时减轻损失的能力之间存在强烈的相关性.
结论:
- 与单体捕获相关的性惩罚在这种催化系统中显著影响了链条传播速率.
- 了解管理对于设计高效的烯酸聚合催化剂至关重要.
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