在Hf催化烯聚合过程中可催化剂效应:考虑到精确定义的Al-基酸盐
Gaia Urciuoli1,2,3, Francesco Zaccaria1,3, Cristiano Zuccaccia2,3
1Department of Chemical Sciences, Federico II University of Naples, via Cinthia, 80126 Napoli, Italy. francesco.zaccaria@unina.it.
Dalton transactions (Cambridge, England : 2003)
|January 10, 2024
概括
新的AlHAl共催化剂对催化聚合具有前景,在各种催化剂中提供高生产率和分子量聚合物. 它避免了休眠位置,与其他催化剂不同.
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:
- 催化剂对于烯酸聚合至关重要,但对催化剂选择非常敏感.
- 催化剂中的自由基可以显著影响催化剂的性能.
研究的目的:
- 研究不同催化剂对催化聚合物的作用.
- 评价一种新的{[iBu2(PhNMe2) Al]2(μ-H)}+[B(C6F5)4]- (AlHAl) 联合催化剂与已建立的系统相比.
主要方法:
- 测试了四种不同的哈夫催化剂:Cs-对称 (Hf-CS-Met) 和C2-对称 (Hf-C2-Met) 的金属,以及八面体 (Hf-OOOO) 和五面协调 (Hf-PyAm) 的后金属.
- 与甲基氨酸 (MAO),改性甲基氨酸和三乙酸/三异的性能进行了比较.
- 分析了催化活性,生产力和聚合物分子重量.
主要成果:
- 甲基氨酸 (MAO) 导致了最差的催化性能.
- 最佳的共催化剂取决于特定的催化剂和性能指标.
- 在所有测试的哈夫催化剂中,AlHAl表现出适合性,在一些 (例如,哈夫) 中产生了更高的生产力.
- AlHAl始终生产高分子量聚合物,即使使用易于链转移到的催化剂.
结论:
- 催化剂的选择对于优化催化烯聚合而言至关重要.
- AlHAl表现出与活性物种形成抑制添加物的低倾向,最大限度地减少休眠部位和终止.
- AlHAl代表了用于先进的烯聚合的多功能和有效的共催化剂.
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