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对单位 styrene 聚合物的辅助连接物效应:第 4 组金属 bis ((phenolate) 催化剂的异特异性
Carmine Capacchione1, Antonio Proto, Henner Ebeling
1Dipartimento di Chimica, Università di Salerno, Via S. Allende, I-84081 Baronissi (SA), Italy.
Journal of the American Chemical Society
|April 24, 2003
概括
具有特定 bis ((phenolato) 连接体的 4 组金属复合物使烯的异型特异性聚合成为可能. 这一进步提供了精确的控制聚合物结构使用甲基氨激活.
科学领域:
- 聚合物化学 聚合物化学
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- styrene聚合对于生产各种聚合物至关重要.
- 实现异位特异性聚合,可以对聚合物特性进行更好的控制.
- 第4组金属复合物是已知的烯聚合物的催化剂.
研究的目的:
- 通过使用新型的4组金属复合物,研究 styrene 的同型特异聚合.
- 探索一个C2-对称协调的1,4-dithiabutane-linked bis(phenolato) 连接体在催化活性中的作用.
- 为了评估甲基氨酸作为激活剂的有效性.
主要方法:
- 合成4组金属复合物,其中包括一个C2对称的bis () 联体.
- 这些复合物的催化测试以检测 styrene 的聚合.
- 使用甲基氨酸激活催化系统.
- 对聚合物微观结构的分析以确定异型特异性.
主要成果:
- 第4组的金属复合物在烯聚合过程中表现出高活性.
- 实现了 styrene 的异型聚合,产生具有受控立体化学的聚合物.
- 对于观察到的催化性能,C2-对称 bis ((phenolato) 配体至关重要.
- 甲基氨酸有效地激活了催化系统.
结论:
- 新型的4组金属复合物与C2-对称 bis ((phenolato) 连接物是同类特异性styrene聚合物的有效催化剂.
- 连接体结构和甲基氨酸酸激活是实现高立体控制的关键因素.
- 这种催化系统为合成明确的聚钢提供了一条新途径.
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