第一个异常长寿命的阳离子微粒:碳-碳化合物混合表面活性剂的自组装
Yukishige Kondo1, Haruhiko Miyazawa, Hideki Sakai
1Department of Industrial Chemistry, Faculty of Engineering, Tokyo University of Science, and Institute of Colloid and Interface Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan.
Journal of the American Chemical Society
|June 6, 2002
概括
这项研究揭示了碳-碳化合物混合表面活性剂在氧化中形成异常稳定的粒,由于分子间的消化,寿命比典型表面活性剂长1000倍.
科学领域:
- 物理化学 物理化学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 表面活性剂在溶液中的行为对于各种应用至关重要.
- 了解菌形成和动态是控制自我组装的关键.
- 碳化合物-碳化合物混合表面活性剂具有独特的特性.
研究的目的:
- 为了研究碳-碳化合物混合表面活性剂在单体和微粒状态之间的交换动态.
- 为了确定由这种混合表面活性剂形成的细胞的寿命和大小.
- 阐明有助于观察到的细胞稳定性的因素.
主要方法:
- 核磁共振 (NMR) 光谱学,特别是19F NMR和1H NMR.
- 对NMR信号进行线形分析,以估计细胞寿命.
- 脉冲梯度旋回回声 (PGSE) 核磁共振来确定微粒的水力动力半径.
主要成果:
- 两个不同的19F核磁共振信号表明,单体和小细胞状态之间的表面活性剂交换缓慢.
- 微粒生命周期 (陶米) 在临界微粒度 (cmc) 测量为2.0毫秒,比传统表面活性剂要长得多.
- 在低度下,PGSE实验揭示了小微粒半径 (0.6 nm),在高度下增加到1.1 nm.
- 有证据表明,分子间消化有助于延长细胞寿命.
结论:
- 碳化合物-碳化合物混合表面活性剂在氧化中表现出异常长的菌寿命.
- 观察到的稳定性归因于表面活性剂分子在微粒结构中的相互排列.
- 这些发现为新型表面活性剂系统的自我组装和动态提供了洞察力.
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