合成,表征和催化行为在异烯聚合物质化中的皮里丁-氧沙-合复合物
Xiuge Hao1, Jin-Kui Liu1, Weize Zhuo1
1College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
Polymers
|March 13, 2024
概括
新的催化剂含有皮里丁-奥克萨林连接体,可以有效地产生cis-1,4-多. 催化剂结构和反应条件显著影响聚合活性,而不是微观结构.
科学领域:
- 协调化学 协调化学
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
背景情况:
- 皮里丁-奥克萨林连接体在协调化学中具有多功能.
- 对于催化应用,还在探索复合物.
研究的目的:
- 合成和表征新型的合复合物. 合成和表征新的合复合物.
- 研究它们在异烯聚合中的催化活性.
- 确定催化剂结构和反应参数对聚合物的影响.
主要方法:
- 合成和表征复合物 (L2CoCl2 3a-h) 的方法.
- 单晶X射线衍射以确定复杂结构.
- 使用活性化复合物的异烯的催化聚合.
- 聚合物分子重量和分散度 (Đ) 的分析.
主要成果:
- 合成和结构特征的复合物 (3a,3d) 与扭曲的四面体中心.
- 皮里丁-奥克萨林连接体作为不寻常的单联接体通过N ((奥克萨林) 协调).
- 活性化复合物显示出高的催化活性 (高达2.5 × 10^6 g·molCo^-1·h^-1) 对于cis-1,4-polyisoprene合成.
- 生产的聚二烯分子重量为4.4-176公斤mol^-1和狭窄的分散度 (1.79-3.42).
- 催化剂结构和反应参数 (共催化剂,温度) 影响了活性,但不影响聚合物微观结构.
结论:
- 新型化-氧化联结的复合物是cis-1,4-多二烯合成的有效催化剂.
- 配体的协调模式和反应条件对于催化性能至关重要.
- 观察到的狭窄的分散性表明一个单位的催化机制.
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