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Updated: Jun 28, 2025

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

Published on: November 27, 2015

具有高温乙烯homo-/co-聚合物的热坚固的氧胺催化剂,具有重的侧臂

Xin Wang^1,2, Lishuang Ma³, Xiaohua Wang^1,2

¹Shandong Provincial College Laboratory of Rubber Material and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China.

|April 13, 2024

概括

新的复合物与氧胺连接体显示出优异的热稳定性,用于高温乙烯聚合. 庞大的侧臂和π-π堆叠相互作用提高了性能,特定的复合体在110°C时表现出色,在150°C以上保持活跃.

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:

复合物与氧胺联体被研究为olefin聚合.
连接物设计对于调整催化剂活性和稳定性至关重要.

研究的目的:

为了合成和表征一系列由三酸氧胺连接体支持的复合物.
评估这些复合物在高温乙烯聚合和共聚化中的热稳定性和催化活性.

主要方法:

使用氧胺配体 (L1-L7) 和TiCl4.4合成复合物 (Ti1-Ti7).
通过1H和13C核磁共振光谱学进行表征.
密度函数理论 (DFT) 计算用于结构优化和相互作用分析.
在高温下对乙烯的同聚合和与1 octene的共聚合中对催化性能的评估.

主要成果:

通过NMR光谱学证实了复合物的成功合成和表征.
DFT的计算揭示了连接物基团和沙利基胺平面之间的稳定 π-π 堆叠相互作用.
复合物表现出良好的热稳定性,使得高温乙烯聚合 (>150°C).
复合体Ti1,Ti4和Ti5在110°C时表现出优异的性能.
催化剂在乙烯/1-奥克共聚合中是活跃的,尽管与适度的合并.

结论:

合成的复合物显示出由于增强的热稳定性而具有高温烯聚合的巨大潜力.
庞大的侧臂和 π-π 堆叠相互作用是实现热强度和催化活性的关键因素.
这些综合体为开发用于专门生产多烯的先进催化剂提供了一个平台.

关键词:

乙烯聚合乙烯的聚合.氧胺氨酸 (phenoxyimine) 是一种氧胺氨酸.解决方案的聚合化.热强度热强度热强度催化剂是一种催化剂.

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