在剪切流下靠近固体表面的表面活性聚合物的结构变化与散装聚合物的结构变化之间的差异
Fumiya Nemoto1, Fumi Takabatake2, Norifumi L Yamada2
1Department of Materials Science and Engineering, National Defense Academy, Yokosuka 239-8686, Japan.
The Journal of chemical physics
|October 22, 2024
概括
研究了表面附近表面活性剂聚合物的剪切诱导结构. 该研究发现,剪切速率的增加速度影响了五乙烯糖醇单乙烯 (C12E5) 囊泡中的结构变化.
科学领域:
- 软物质物理学 软物质物理学
- 表面科学是一门科学.
- 材料化学 材料化学
背景情况:
- 非离子表面活性剂,如乙烯糖醇单乙烯 (C12E5) 在水中形成多层层囊泡.
- 剪切应用通常会诱导表面活性剂层的屈曲不稳定性.
- 固体基板附近的限制效应可以改变膜波动,但近表面的结构变化尚未研究.
研究的目的:
- 为了研究表面活性剂聚合物的结构变化,在切割下接近固体基板.
- 了解剪切率上升对近地表面结构的影响.
主要方法:
- 用中子反射计 (NR) 来分析结构变化.
- 控制的剪切速率被应用到固体基板之间限制的表面活性剂溶液中.
主要成果:
- 在低剪速时观察到剪切变厚,在高剪速时观察到剪切变薄,与散装行为一致.
- 检测到板状结构的不连续变化和基板附近的表面活性剂凝结.
- 证明了剪切速率坡速度控制了剪切诱导的结构.
结论:
- 这项研究提供了首个关于剪切率上升速度控制表面活性聚合物的近表面结构化的实验证据.
- 接近表面的结构重组不同于在剪切下的散装行为.
- 中子反射计对于在剪切软物质中探测界面现象是有效的.
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