在Langmuir单层中混合: perfluorotetradecanoic酸和一个没有链接器的Gemini表面活性剂
Srikant Kumar Singh1, Wei Bu2, Pan Sun2
1Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9, Canada.
Langmuir : the ACS journal of surfaces and colloids
|November 6, 2023
概括
将双子表面活性剂与化表面活性剂混合显示出非理想的行为和空气-水界面的相分离. 这项研究阐明了这些二元表面活性剂混合物的分子间相互作用.
科学领域:
- 表面化学 表面化学
- 材料科学是一种材料科学.
- 超分子化学 超分子化学
背景情况:
- 阴性双子表面活性剂,特别是"没有链接器的双子"类型,如C18-0-C18,在接口上形成晶体单层.
- perfluorinated 表面活性剂,如 perfluorotetradecanoic 酸 (PF),是接口研究的基准材料.
研究的目的:
- 研究C18-0-C18与PF混合对单层性质的影响.
- 了解空气-水界面上的二元表面活性剂系统中的混合行为和相分离.
主要方法:
- 表面压力面积 (π-A) 是异热体.
- 测量表面潜力的测量.
- 对单层的直接可视化.
- 在空气-水界面的草地事件X射线衍射 (GIXD).
主要成果:
- C18-0-C18和PF混合物表现出非理想的混合和相位分离.
- 单层稳定性和歇斯底里表现出与成分相关的趋势,C18-0-C18 < PF < 50% PF.
- 混合膜的结晶学数据是单个组件的模式的组合,表明不同的分子间安排.
结论:
- 这项研究阐明了空气-水界面上的二元表面活性剂混合物的分子间行为.
- 阶段分离和非理想的混合是这个C18-0-C18/PF系统的关键特征.
- GIXD为混合表面活性剂单层的结构组织提供了宝贵的见解.
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