使用化二博联合启动剂的异布烯聚合
Stewart P Lewis1, Nicholas J Taylor, Warren E Piers
1Department of Polymer Science, University of Akron, Akron, OH 44325-3909, USA.
Journal of the American Chemical Society
|December 4, 2003
概括
易斯酸二博对异布丁聚合物化是有效的. 它与化和乙醇形成稳定的离子对,在更高的温度下可以进一步反应.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物化学 聚合物化学
背景情况:
- 易斯酸二博是异布丁聚合物的强有力的启动剂.
- 了解二博与电友性物种的反应机制对于控制聚合是至关重要的.
研究的目的:
- 为了研究易斯酸性二博与基化物和基甲基乙醇的反应途径.
- 用先进的光谱技术来描述这些反应中形成的中间物种.
主要方法:
- 使用了可变温度1H和19F核磁共振 (NMR) 光谱.
- 使用X射线晶体学来确定特定离子对的结构.
主要成果:
- 稳定的离子对 (2a,2b) 在低温下在二博和电友性试剂之间形成.
- 在高温下,这些离子对经历循环形成-1,3,3-三甲基 (3) 或离子降解.
- 与Ph3C-Cl的反应产生了一个独特的离子对 (4),与一个弱相关的mu-Cl对离子产生反应.
结论:
- 迪波兰的易斯酸性促进了反应性离子对的形成.
- 观察到的反应突出显示了复杂的机械路径,涉及 diborane 在阴离子聚合起始.
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