在单层薄膜的压缩/松过程中,由键诱导的歇斯底里
Jennifer L Sorrells1, Fredric M Menger
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
Journal of the American Chemical Society
|July 16, 2008
概括
具有二基托皮帕拉зин环的新型表面活性剂表现出不寻常的特性,如高克拉夫特温度和低临界菌度. 由于环状,它们的单层显示出独特的歇斯底里.
科学领域:
- 超分子化学 超分子化学
- 表面化学 表面化学
- 材料科学 材料科学 材料科学
背景情况:
- 表面活性剂对于各种应用至关重要,但它们的特性可以通过分子设计来调整.
- 狄基托皮佩拉津 (DKP) 部分具有独特的结构和结合能力.
- 了解接口行为是设计先进的两系统的关键.
研究的目的:
- 合成和表征新型表面活性剂,其中包括一个二基托皮佩拉зин (DKP) 环.
- 研究DKP环对表面活性剂溶解度,聚合行为和界面性质的影响.
- 探索含有DKP的两动物独特的压力/面积等温和和单层行为.
主要方法:
- 表面活性剂的立体异构体的合成,具有可变的碳化合物链和阳离子头组.
- 使用高性能液态染色学 (HPLC),导电性测量和表面张力分析进行表征.
- 核磁共振 (NMR) 和不溶性单层的压力/面积等温的扩散研究.
主要成果:
- 合成的表面活性剂具有较低的水溶性,较高的克拉夫特温度和较低的临界微粒度 (CMC).
- 在最初的压缩/放松周期中,非类同类物体在压力/面积等热体中表现出前所未有的歇斯底里.
- 这种歇斯底里症归因于在空气/水界面上滴滴氨酸环的方向.
结论:
- 基托皮佩拉зин环的结合显著影响表面活性剂的物理化学性质.
- DKP环的重定向和在接口上形成稳定的键的能力解释了观察到的单层行为.
- 这些发现为设计具有可调节界面特征的功能表面活性剂开辟了道路.
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