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调整 2,3-Bis ((arylimino) butan-nickel 高分子量聚乙烯弹性体的预催化剂

Dongzhi Zhu^1,2, Dedong Jia², Qiuyue Zhang²

¹Guangxi Key Laboratory of Advanced Structural Materials and Carbon Neutralization, School of Materials and Environment, Guangxi Minzu University, Nanning 530105, China.

Molecules (Basel, Switzerland)

|May 7, 2025

概括

新的催化剂与重的配体显示在乙烯聚合的高活性,产生超高分子量聚乙烯与调节性质和优良的弹性回收先进材料.

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

背景情况:

α-diiminonickel复合物的催化性能对连接物结构敏感.
固态要求和电子捐赠小组可以影响催化剂的行为.

研究的目的:

为了合成和表征新的不对称的2,3-bis ((arylimino) butan-nickel复合物.
评估这些复合物的乙烯聚合活性和效率.
研究由此产生的聚乙烯的特性及其潜在应用.

主要方法:

不对称的2,3-bis ((arylimino) butan-nickel复合物的合成,具有特定的连接物修饰.
使用FTIR,元素分析和单晶X射线衍射进行了表征.
使用活性复合物的乙烯聚合,并分析聚合物的特性.

主要成果:

合成的复合体显示出偏离理想的四面体几何.
取得了特殊的乙烯聚合活性 (在20°C时高达13.67 × 10⁶g PE mol^-1 (Ni) h^-1,在80°C时保持高活性).
生产的聚乙烯具有超高分子量 (3.33-19.47 × 10⁵ g mol^-1),可调节的分支 (84-217/1000C),以及出色的机械/弹性性能.

结论:

设计的复合体在乙烯聚合过程中表现出卓越的催化性能.
聚乙烯的性能,包括分子量和分支,可以通过聚合温度控制.
由此产生的聚乙烯具有出色的弹性回收,对高性能热塑性弹性体应用具有前景.

关键词:

具有高分子量的分子量.聚乙烯弹性体聚乙烯弹性体结构上的修改.不对称的2,3-bis ((arylimino) -复合体.

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