催化乙烯与乙烯氧化合聚合:一项计算研究
Zhihui Song1, Rong Gao1, Changjiang Wu2
1Department of Polyethylene, SINOPEC (Beijing) Research Institute of Chemical Industry Co., Ltd., Beijing 100013, China.
Polymers
|March 28, 2024
概括
这项研究揭示了催化剂可以与乙烯 vinyltrimethoxysilane 共聚合乙烯,为提供了一个具有成本效益的替代品. 该研究阐明了反应机制,确定了影响功能化聚乙烯生产的关键步骤和硬质因素.
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:
- α-二胺催化剂在乙烯聚合和与极性单体的共聚化方面表现出色.
- α-二胺催化剂在乙烯/极性单体共聚化中通常表现不佳.
- 最近的进展表明,催化剂可以有效地与乙烯氧化乙烯一起聚合乙烯,产生功能化的聚乙烯.
研究的目的:
- 通过使用布鲁克哈特型催化剂,研究乙烯与乙烯三氧化 (VTMoS) 联合聚合的机制.
- 为这个独特且具有成本效益的催化系统提供分子层面的理解.
- 为了比较催化剂的性能与昂贵的同行.
主要方法:
- 密度功能理论 (DFT) 的计算被用来优化复合物和活性物种.
- 对于同聚合和共聚合的链启动,传播和终结的机械探索.
- 链内和链末西兰链的能量分析,包括极地基板分布.
主要成果:
- 链启动是由α-二胺Ni复合体催化的乙烯同聚合的主要步骤.
- 对VTMoS的1,2和2,1插入的类似能量障碍解释了对五和四成员酸盐的实验观测.
- 在VTMoS插入后重新插入乙烯是决定速度的步骤,受到硬质障碍的影响.
结论:
- 布鲁克哈特型催化剂为乙烯/VTMoS共聚合提供了一个可行的,具有成本效益的替代方案.
- 连锁结尾试用koxysilane结合的主要途径涉及链路行走,环开放和乙烯插入.
- 锡兰基与进来的乙烯之间的绝缘排斥有利于链末的链内合并.
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