基板稳定的卡比尔伊米诺皮里迪尔NiII复合物用于olefin聚合
Hasaan S Rauf1, Yu-Sheng Liu1, Muhammad Arslan1
1Department of Chemistry, Center of Excellence in Polymer Chemistry (CPEC), University of Houston, 3589 Cullen Boulevard, Houston, Texas 77004, United States.
ACS catalysis
|September 12, 2024
概括
新的催化剂通过化物抽象激活,使得无需复杂的连接体设计,可以控制多烯结构. 这种方法利用明确的离子对来实现更高的分子量和量身定制的分支.
科学领域:
- 催化剂是一种催化剂.
- 聚合物化学 聚合物化学
- 有机金属化学 有机金属化学
背景情况:
- 传统的Ni催化烯聚合工艺在很大程度上依赖于连接体设计来控制多烯结构.
- 尼II预催化剂的激活过程通常涉及到in situ化,这可能是复杂的,并限制了催化剂的范围.
研究的目的:
- 开发仅通过化物提取激活的稳定于空气的Ni(II) 预催化剂.
- 为了研究催化剂衍生的离子对在烯聚合中的作用.
- 通过操纵激活过程来实现对聚烯分子重量和微观结构的更广泛控制.
主要方法:
- 设计和合成空气稳定的基或基功能化Ni (II) 预催化剂.
- 使用有机和有机共催化剂激活预催化剂.
- 在高乙烯压力下进行聚合研究.
- 密度函数理论 (DFT) 计算以阐明反应机制.
主要成果:
- 通过化物抽象激活的前催化剂与传统方法相比,产生了更高分子量的同型/共聚物.
- 有机可催化剂形成了明确的离子对,导致比有机可催化剂更受控的聚合.
- 高乙烯压力使得分支密度更大,并逐渐纳入短链分支.
- 与甲基替代类似物相比,桥梁碳上的基增加了聚合物的分子量.
结论:
- 通过化物提取激活的稳定于空气的Ni(II) 预催化剂为聚烯胺合成提供了一条新的途径.
- 离子对相互作用对于控制聚合结果至关重要,精确定义的离子对促进了更高的分子量.
- 这种方法为调整多聚烯微型和宏型结构提供了一个多功能平台,减少了对复杂连接体设计的依赖.
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