作为烯聚合抑制剂的二甲基形式胺杂质.
Joaquín Hernández-Fernández1,2,3, Rafael González-Cuello4, Rodrigo Ortega-Toro4
1Chemistry Program, Department of Natural and Exact Sciences, San Pablo Campus, University of Cartagena, Cartagena 130015, Colombia.
Polymers
|September 28, 2023
概括
甲基甲胺 (DMF) 通过强烈结合中心来抑制齐格勒-纳塔催化烯聚合. 增加DMF度降低了催化剂活性,并改变了聚合物特性,如化流量指数.
科学领域:
- 聚合物化学 聚合物化学
- 催化科学 催化科学
- 材料科学 材料科学 材料科学
背景情况:
- 齐格勒-纳塔催化剂对于烯聚合是至关重要的.
- 了解抑制剂效应是控制聚合物特性的关键.
- 甲基甲胺 (DMF) 作为一种潜在的聚合抑制剂正在研究中.
研究的目的:
- 用齐格勒-纳塔催化剂研究二甲基形式胺 (DMF) 对烯聚合物的影响.
- 分析DMF如何影响催化剂活性,聚合物分子量和分支.
- 确定DMF与催化剂系统之间的相互作用机制.
主要方法:
- 实验性聚合以不同的DMF度进行.
- 分析催化剂活性,聚合物分子量和融化流量指数 (MFI).
- 计算方法包括吸附能量和分子轨道计算.
主要成果:
- 随着DMF/Ti比率的增加,催化剂活性显著下降.
- 化流量指数 (MFI) 损失75%在89.92ppm的DMF中观察到,这表明流动性增加.
- 与烯 (~ -5.2 kcal / mol) 相比,DMF对中心具有强烈的亲和力 (吸附能 ~ -46.157 kcal / mol).
结论:
- 甲基甲胺 (DMF) 在齐格勒-纳塔催化烯聚合过程中起到有效的抑制作用.
- DMF与催化剂的中心的强烈结合亲和力是抑制的主要机制.
- 这种相互作用进一步得到了有利的HOMO-SOMO能量差距的支持,影响了聚合动力学和聚合物特性.
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