通过哈夫尼介导的高度同型特异性共聚合物获得功能化的超高分子量多 (α-olefin)
Guanglin Zhou1,2, Hongliang Mu1, Zhongbao Jian1,2
1State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Renmin Street 5625, Changchun, 130022, China.
Macromolecular rapid communications
|May 16, 2024
概括
具有异原子组的新型胺催化剂显著增强α-olefin聚合和共聚合,产生高分子量聚合物. 催化剂Cat-CF3产生了分子量最高的同位性聚合物.
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:
- 众所周知,含有异原子的组会影响过渡金属催化剂的活性.
- 胺连接物在过渡金属早期催化中是有效的.
研究的目的:
- 设计和合成具有不同异构原子替代物 (OMe,CF3,C6F5) 的新型胺哈催化剂.
- 评估这些新催化剂在α-olefin聚合和与极性单体共聚的性能.
- 研究催化剂修饰和极性单体合并对聚合物的特性,特别是分子量和立体选择性的影响.
主要方法:
- 用OMe,CF3和C6F5替代物的新型胺哈催化剂的合成.
- 使用合成的催化剂和已建立的基准 (Cat-H,Cat-iPr) 来聚合α-olefins (1-hexene,1-octene,4M1P).
- α-olefins与设计的极性单体的共聚化.
- 聚合物分子量 (Mw) 和立体选择性的分析.
主要成果:
- 所有新的催化剂都在α-olefin聚合中表现出高活性.
- 催化剂Cat-CF3产生了具有最高分子量 (1649公斤mol-1) 的同位性聚合物.
- 催化剂Cat-OMe在与极性单体的共聚化中产生了具有最高分子量 (2990公斤mol-1) 的同位性共聚合物.
- 催化剂Cat-C6F5在聚-α-olefin合成中表现出降低的立体选择性.
结论:
- 在pyridylamido hafnium催化剂中含有异性原子的组可以显著增强聚合物分子重量并影响立体选择性.
- 这些发现凸显了改造早期过渡金属催化剂以合成具有定制性质和新型结构的聚合物的潜力.
- 开发的催化剂为先进的聚合物合成提供了有前途的途径,特别是对于高性能材料.
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