| 摘要: |
| 超疏水性表面的液滴撞击是普遍存在的现象,研究具有不同尺寸和形状宏观结构的超疏水性表面对液滴撞击行为和接触时间的影响,对于其潜在应用具有重要的理论指导作用。 采用等离子体纳米织构化方法在平整与具有矩形、半圆形和三角形宏观结构的聚乙烯表面上制备超疏水性纳米线结构,通过高速摄像机观察超疏水性聚乙烯表面的液滴撞击行为,分析撞击液滴的形状演变和接触时间变化。 研究表明:超疏水性聚乙烯表面的矩形、半圆形和三角形宏观结构可显著改变液滴的撞击行为,液滴铺展后回缩过程的缩减加速了超疏水性表面液滴的弹离,有效降低了超疏水性表面的固液接触时间。 超疏水性聚乙烯表面的矩形、半圆形和三角形宏观结构尺寸小于液滴直径时,均可造成高速撞击液滴分裂,液滴的分裂回弹导致固液接触时间进一步降低,接触时间最低可达到约 4. 8 ms。 疏水性表面的宏观结构有利于固液接触时间降低,具有宏观结构的疏水表面展现出抗水滴高速撞击的去润湿性能。 |
| 关键词: 超疏水性 宏观结构 接触时间 撞击行为 |
| DOI：10.11933/j.issn.10079289.20210429003 |
| 分类号:TG156;TB114 |
| 基金项目:国家自然科学基金资助项目(51975086, 52111530043, 51611530706) |
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| Effect of Macrostructures on Impacting Behaviors of Water Droplets on Superhydrophobic Polymer Surfaces |
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LI Xiaoyu, LI Yupeng, HUO Lei, LEI Mingkai
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School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 , China
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| Abstract: |
| Impact of droplet is a common phenomenon on the superhydrophobic surfaces. To study the effect of macrostructures with different morphologies and sizes of the superhydrophobic surfaces on the contact behaviors and contact time of water droplets during impacting is the potential applications of the superhydrophobic surfaces. The plasma nanotexturing was used to fabricate the superhydrophobic polyethylene (PE) surfaces with rectangle, semicircle and triangle macrostructures. The impacting processes of water droplets at different impact speed on the superhydrophobic PE surfaces were investigated by a high-speed camera and the evolution of the solid-liquid contact behaviors and contact time during impacting of water droplets were analyzed. The results showed that the rectangle, semicircle and triangle macrostructures on the superhydrophobic PE surfaces remarkably changed the contact behaviors of water droplets during impacting. The elimination of the retraction process of water droplets after spreading accelerated the rebound of water droplets to decrease powerfully the solid-liquid contact time on the superhydrophobic surfaces. The breaking of water droplets into small droplets during impacting was observed on the superhydrophobic surfaces with the rectangle, semicircle and triangle macrostructures smaller than the diameters of droplets. The rebounding of small droplets resulted in a further reduction in the solid- liquid contact time that can reach~ 4. 8 ms. The macrostructures on the superhydrophobic PE surfaces benefit to reduce the solid-liquid contact time. The superhydrophobic surface with macrostructures exhibits antiwetting property under the impacting droplet at a high speed. |
| Key words: superhydrophobic macrostructure contact time contact behavior |
