溶剂对循环多聚甲基的战术性的影响
Sung-Min Hyun1, Arkadios Marathianos2, Parker T Boeck1,3
1University of Florida, Department of Chemistry, Center for Catalysis, P.O. Box 117200, Gainesville, FL, 32611, USA. veige@chem.ufl.edu.
Chemical communications (Cambridge, England)
|November 8, 2023
概括
溶剂的选择显著影响了周期性聚甲基合成期间的聚合物战术性. 托卢有利于cis,syndiotactic结构,而THF产生cis,syn/iso的战术性.
科学领域:
- 聚合物化学 聚合物化学
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 策略性,在聚合物链中重复单元的立体化学排列,是聚合物性质的关键决定因素.
- 在聚合过程中控制战术性对于定制材料特性至关重要.
- 循环多化基 (c-PNB) 合成为研究立体化学控制提供了一个平台.
研究的目的:
- 研究不同溶剂对通过催化方法合成的循环多聚乙烯 (c-PNB) 战术性的影响.
- 了解溶剂极性和协调能力如何影响c-PNB聚合中的立体化学结果.
- 为了建立反应介质和产生的聚合物微观结构之间的关系.
主要方法:
- 诺波伦烯的催化聚合形成循环结构.
- 使用多烯和四水 (THF) 进行溶剂选.
- 使用光谱技术 (例如NMR光谱) 分析聚合物战术性.
主要成果:
- 在二烯中,聚合主要产生 cis,syndiotactic 循环多二烯.
- 在四基 (THF) 中,观察到cis,syndiotactic 和 cis,isotactic 循环多基的混合物.
- 溶剂直接影响聚合物的立体化学路径.
结论:
- 溶剂的选择是控制循环多聚乙烯的战术性的一个关键参数.
- 独特的溶剂效应突出显示了在催化活性部位中溶剂-配体相互作用的重要性.
- 这项研究为设计催化剂和反应条件提供了洞察力,以实现特定的聚合物微观结构.
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