增强高活性和可调节的单体链的异烯聚合,使用循环合伊米诺皮里丁铁前催化剂
Nighat Yousuf1,2,3, Yanping Ma1, Qaiser Mahmood2
1Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. whsun@iccas.ac.cn.
Dalton transactions (Cambridge, England : 2003)
|December 12, 2023
概括
新的铁复合物有效催化异二烯聚合,产生高分子量聚二烯. 最好的预催化剂表现出高活性和热稳定性,允许控制聚合物微观结构.
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:
- 开发高效的催化剂以聚合异二烯是生产合成聚二烯的关键.
- 铁复合物为传统聚合催化剂提供了成本高效和可调节的替代品.
- 结构刚性的配体可以影响催化剂活性和聚合物特性.
研究的目的:
- 为了合成和表征新型的循环基融合的伊米诺皮里丁铁复合物.
- 通过使用甲基氨酸联合催化剂,研究它们作为异烯聚合物的前催化剂的性能.
- 探索连接体结构和反应条件对催化活性和聚合物微观结构的影响.
主要方法:
- 铁复合物的一个合成.
- 使用FTIR,元素分析和单晶X射线衍射进行结构性表征.
- 使用不同催化剂负载,温度和体硬质障碍的异烯聚合研究.
主要成果:
- 成功合成了结构刚性循环环合的伊米诺皮里丁铁复合体.
- 最活跃的前催化剂 (FeH) 证明了高分子量聚烯的产生,转化率>99%.
- 在低催化剂负载 (0.0025 mol%) 和广泛的热稳定性 (-20 °C 到 100 °C) 的情况下,异常活性 (4.0 × 10^6 g_PI (mol_Fe,h) ^-1).
- 可调节的1,4/3,4区域选择性 (9/91至69/31) 和高cis-1,4立体选择性 (>99/1) 通过调整固态替代剂和温度来实现.
结论:
- 连接体框架中的固体阻碍在异烯聚合过程中显著影响了催化性能.
- FeH预催化剂表现出卓越的活性,稳定性和对聚合物微观结构的控制.
- 这些发现凸显了定制铁复合物的潜力,以实现高效和选择性的异烯聚合.
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