-胺 (FA) 和复合物:合成,结构和在烯酸聚合物中使用
Thu-Van Nguyen1, Mehmet Jahja1, Jérôme Bayardon1
1Université Bourgogne Europe, CNRS, ICMUB UMR 6302, Dijon F-21000, France.
Inorganic chemistry
|January 9, 2026
概括
合成了新的和二 (基胺) 复合物,并进行了聚合测试. 这些催化剂产生了具有广泛分子量分布的高分子量聚乙烯,表明了多站点行为,而烯聚合则显示了单站点特性.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
背景情况:
- 双基胺基) 连接物为金属复合提供可调节的固态和电子特性.
- 和复合物被广泛研究为烯聚合物的催化剂.
研究的目的:
- 合成和表征新的双和双甲基和复合物.
- 评估这些复合物在乙烯和烯聚合中的催化活性.
- 研究连接物替代剂对聚合性能和聚合物特性的影响.
主要方法:
- 合成二氧化和的复合物.
- 固态结构分析 (X射线衍射).
- 溶液状态的表征 (NMR光谱学).
- 乙烯和的催化聚合利用甲基氨酸 (MAO) 作为辅助催化剂.
- 聚合物特性 (分子量,分子量分布,微观结构).
主要成果:
- 成功合成了新型 bis (氧胺氨酸) Ti 和 Zr 复合物 [FA) 2MX2] .
- 固态结构呈现出扭曲的八面体几何形状,具有特定的O-trans,N-cis,X-cis配置.
- 溶液NMR研究显示,所有复合物的单个C2对称异构体存在.
- 乙烯聚合产生了线性,超高分子量聚乙烯 (Mw高达2,154,000 g/mol) 具有广泛的分子量分布 (Mw/Mn = 14-408),表明多站点催化.
- 在阿里洛基环上含有 tert-butyl 替代物的复合物显示出增强的聚合生产率 (高达 230 kgPE/molcat/h).
- styrene 聚合显示中度活性 (2-39 kgPS/molcat/h),产生具有表明单位行为特征的 atactic 聚烯 (Đ = 1.77-1.86).
结论:
- 合成的基胺 Ti 和 Zr 复合物是乙烯和烯聚合的活性催化剂.
- 乙烯聚合过程通过多位机制进行,产生高分子量聚合物.
- styrene聚合物化表现出单位行为,产生性聚烯.
- 连接物设计,特别是添加三丁基,可以显著提高催化剂的生产率.
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