双核氨基-氧化稀土金属复合物:合成和它们在异烯聚合中的催化性能
Xuyang Yan1, Wentao Chen1, Wang Xie2
1Department of Polymer Materials, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China.
Inorganic chemistry
|July 1, 2024
概括
新的双核稀土金属催化剂有效聚合异烯,产生高-1,4-正规聚合物. 双核系统表现出增强的稳定性和活性,证明了独特的双核效应.
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:
- 稀土金属复合物越来越多地被研究为烯聚合物的催化剂.
- 设计新的配体对于调整催化剂性能和聚合物特性至关重要.
- 由于合作效应,双核复合体在单核类型相比具有潜在的优势.
研究的目的:
- 为了合成和表征新的双核稀土金属复合物与氨酸-氧化联体.
- 为了评估这些复杂物在异烯聚合过程中的催化性能.
- 调查桥接连体和金属中心特性对催化活性和选择性的影响.
主要方法:
- 合成双核稀土金属复合物与各种桥接烯基部分 (Para-phenyl,Meta-phenyl,Naphthalenyl,Anthracenyl) 的合成.
- 使用核磁共振 (NMR) 光谱和X射线衍射进行结构性表征.
- 用[Ph3C][B(C6F5) [4]激活后对异烯聚合物的催化评估.
- 分析聚合物微结构 (cis-1,4规律) 和分子量.
主要成果:
- 成功合成并证实了稀土金属复合物的双核结构.
- 所有激活复合物都有效催化了异烯聚合,产生高分子量聚合物,高达96.1%的cis-1,4规律.
- 立体/电子效应和金属半径显著影响了催化活性和cis-1,4-选择性.
- 双核伊特催化剂与帕拉桥证明了与其单核对应物相比更高的热稳定性和催化效率.
结论:
- 新型双核稀土金属氨酸-氧化酸复合物是异烯聚合物的有效催化剂.
- 桥接联体的结构和稀土金属的性质在催化性能中起着关键作用.
- 观察到一种明显的双核效应,增强了催化剂的稳定性和效率,特别是在伊系统中.
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