在状系统中,连续与细分的疏水性
Fredric M Menger1, Ashley L Galloway
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA. menger@emory.edu
Journal of the American Chemical Society
|December 2, 2004
概括
将基引入表面活性剂链中会产生两种不同的类别. 一类表现出较差的体性质,而另一类表现出正常到增强的性能,影响表面活性剂的自组装和应用.
科学领域:
- 合体和表面化学
- 表面活性剂科学 表面活性剂科学
- 聚合物化学 聚合物化学
背景情况:
- 表面活性剂在各种应用中至关重要,其属性是由分子结构决定的.
- 碳化合物链在表面活性剂中是典型的,但它们的修改提供了新的可能性.
- 在表面活性剂链中对非碳化合物功能的系统研究不足.
研究的目的:
- 研究将非碳化合物功能,特别是基,插入到表面活性剂链中的影响.
- 了解这些修改如何影响表面活性剂的合性质.
- 发现和表征链改性表面活性剂的新类.
主要方法:
- 合成含有基的两类链改性表面活性剂.
- 自组装行为的特征,包括总体大小和组装方式.
- 评估接口属性,例如空气/水接口的占用面积.
- 在固体吸附和溶解 (梅西乙烯) 的性能评估.
主要成果:
- 确定了两种不同的链式改性表面活性剂类别.
- 1类表面活性剂显示非合作性自我组装,形成小聚合物,低发泡,高界面面积和弱吸附/溶解.
- 2类表面活性剂表现出正常到增强的特性,其中一些在乙烯溶解度上超过了传统表面活性剂.
- 差异与碳化合物链分段和最长段的位置有关.
结论:
- 表面活性剂的细分水性,即使插入了基,也可以诱导聚合.
- 碳化合物细分的程度和位置显著改变了成薄膜和片的自我组装模式.
- 链式改性表面活性剂具有可调节的特性,在特定应用 (如溶解) 中有可能提高性能.
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