软湿:在柔软的超水表面上滴滴落下来的接触角度
Youhua Jiang1,2,3, Zhijia Xu1, Bin Li1,2,3
1Department of Mechanical Engineering (Robotics), Guangdong Technion─Israel Institute of Technology, Shantou, Guangdong 515063, China.
Langmuir : the ACS journal of surfaces and colloids
|October 19, 2023
概括
柔软的超疏水表面表现出独特的滴滴行为. 随着柱子的柔软性而降低下降的接触角度,而密集的包装可以增加角度,与刚性表面不同.
科学领域:
- 表面科学是一门学科.
- 材料科学 材料科学 材料科学
- 流体动力学 流体动力学
背景情况:
- 滴滴退缩的接触角度对于超水性表面的湿透性和粘附性至关重要.
- 软表面结构,机械性能和滴滴行为之间的定量联系尚未得到充分理解.
研究的目的:
- 调查软柱阵列的机械性能与滴滴退缩接触角度之间的相关性.
- 了解在柔软的超疏水表面上控制滴滴柱相互作用的基础物理.
主要方法:
- 系统地改变软柱阵列的几何尺寸和机械性能 (弹常数).
- 在不同的条件下测量滴滴回落的接触角度.
- 开发了一种结合毛细管和弹性的分析模型.
主要成果:
- 随着支柱弹常数的减少 (柔软度的增加),倒退的接触角度会减少.
- 密集的柱子可以产生比稀疏的柱子更大的退缩接触角度,与刚性表面相反.
- 毛细体的集体效应,液体-蒸汽界面扭曲和柱子偏移影响滴滴的分离.
结论:
- 柔软的超疏水表面的机械性能显著影响滴滴退缩的接触角度.
- 一个分析模型准确地根据材料特性,柱体几何形状和机械特性预测退缩的接触角度.
- 这些发现挑战了对刚性表面的现有范式,并为软超性材料提供了新的设计原则.
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