动态核极化NMR光谱允许微孔有机聚合物的高通量表征
Frédéric Blanc1, Samantha Y Chong, Tom O McDonald
1Department of Chemistry, §Stephenson Institute for Renewable Energy, and ‡Center for Materials Discovery, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom.
Journal of the American Chemical Society
|September 14, 2013
概括
动态核极化 (DNP) 固态NMR显著提高了微孔有机聚合物的信号噪声比. 这种先进的技术使得分子结构的详细确定和聚合物库的高通量表征成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 分析化学 分析化学
背景情况:
- 微的有机聚合物是复杂的网络,具有具有挑战性的结构特征.
- 固态核磁共振 (NMR) 光谱对于分析聚合物结构至关重要.
- 传统的核磁共振方法通常具有低灵敏度,限制了详细分析.
研究的目的:
- 应用动态核极化 (DNP) 增强的固态NMR,以改善微孔有机聚合物的特征.
- 为了实现自然丰富的 (13) C 和 (15) N 交叉极化神奇角度旋转 (CP MAS) NMR 频谱的高信号噪声比.
- 为了使高分子库的高效,高吞吐量分析.
主要方法:
- 使用了动态核极化 (DNP) 与二氧化二基.
- 采用固态核磁共振 (NMR) 光谱,特别是 (13) C 和 (15) N CP MAS.
- 在高磁场 (14.1 T) 和低温度 (∼105 K) 进行实验.
主要成果:
- 获得了超过10倍的灵敏度增强.
- 获得了高质量的自然丰富性 (13)C和 (15)N CP MAS NMR光谱.
- 揭示了复杂聚合物网络分子结构的前所未有的细节.
结论:
- DNP固态核磁共振是一种强大的技术,用于微孔有机聚合物的详细结构分析.
- 该方法促进了组合聚合物库的高效,高通量表征.
- 这种方法显著推进了对复杂聚合物材料的研究.
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