固态91Zr核磁共振光谱对烯聚合物聚合催化剂前体的研究
Aaron J Rossini1, Ivan Hung, Samuel A Johnson
1Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada N9B 3P4.
Journal of the American Chemical Society
|December 7, 2010
概括
这项研究表明,91Zr固态NMR (SSNMR) 光谱是分析conocene复合物的强大工具. 该技术提供了详细的分子结构信息,对于了解烯酸聚合催化剂至关重要.
科学领域:
- 固态NMR光谱学 固态NMR光谱学
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
背景情况:
- conocene复合物是olefin聚合中的重要催化剂.
- 了解这些催化剂的精确分子结构对于优化它们的性能至关重要.
- 固态NMR (SSNMR) 光谱学提供了一种潜在的途径,以非破坏性的方式探测这些结构.
研究的目的:
- 调查91Zr SSNMR光谱对一系列conocene化合物的特征的有用性.
- 建立SSNMR参数与这些复合物的分子结构之间的相关性.
- 确定可靠的方法来计算91Zr电场梯度 (EFG) 和化学转移 (CS) 张量.
主要方法:
- 获取各种conocene复合物的静态和魔法角旋转 (MAS) 91Zr SSNMR光谱.
- 测量 91Zr EFG 和 CS 张量参数和欧勒角.
- 量子化学计算以确定EFG和CS张量.
- 在分子框架内的张量定向的可视化.
主要成果:
- 成功获得了各种conocene化合物的91Zr SSNMR光谱.
- 确定了91Zr EFG和CS张量参数及其相对方向.
- 确定了准确的计算方法来预测这些NMR参数.
- 在NMR张量参数,分子对称性和结构之间建立了明确的联系.
结论:
- 91Zr SSNMR光谱是一种多功能技术,用于探测conocene复合物的分子结构.
- 该技术可以区分各种结构图案和对称性.
- 这种方法对同质和异质烯酸聚合催化剂的表征具有显著的前景.
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