复合物的催化行为 携带在异烯聚合物中的胺-氧化物联体在异烯聚合中
Yuanxu Du1,2, Shuo Gao1, Hui Ma1
1School of Chemistry and Chemical Engineering, Linyi University, Linyi 276000, China.
Polymers
|December 23, 2023
概括
新的复合物与二氧化配体在异烯聚合过程中表现出高活性. 这些催化剂产生具有受控微观结构的高分子量聚二烯,为先进的聚合物合成提供了潜力.
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:
- 科巴尔特复合物在烯聚合过程中被研究其催化活性.
- 二氧化物配体为金属中心提供独特的协调环境.
- 异烯聚合对于生产具有特定性质的合成至关重要.
研究的目的:
- 合成和表征新型 (II) 复合物与二氧化物-氧化物连接体.
- 评估这些复杂物在异烯聚合过程中的催化性能.
- 研究反应参数对聚合活性和聚合物微观结构的影响.
主要方法:
- 通过使用各种胺-氧化物联体,合成四种 (II) 复合物 (Co1-Co4).
- 使用FT-IR,质谱,元素分析和单晶X射线衍射 (对于Co2) 进行了表征.
- 通过二甲基化 (AlClEt2) 在烯中激活的异烯聚合实验.
主要成果:
- 复杂的CO2具有扭曲的八面体中心,由两个6 - 甲基二 - 二氧化连接体协调.
- 复合物Co1-Co4在异烯聚合过程中表现出异常高的催化活性 (高达16.3×10^5 (mol的Co) ^-1(h) ^-1).
- 由此产生的聚二烯具有高分子量,狭窄的分子量分布和高的cis-1,4选择性.
结论:
- 合成的复合物是异烯聚合的高效催化剂.
- 催化剂类型,共催化剂和温度影响聚合活性,但不影响聚合物微观结构.
- 这些发现为合成高性能聚二烯提供了一个有前途的途径.
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