Wet-adhesion properties of microstructured surfaces inspired by newt footpads
Wet-adhesion properties of microstructured surfaces inspired by newt footpads
复制标题
受蝾螈足垫启发的微结构表面的湿粘附特性
DOI：
10.1088/1361-665x/aad6d2
复制
发表时间：
2018-11-01
影响因子：
4.1
通讯作者：
Wang, Xiaojie
中科院分区：
文献类型：
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作者：
Gong, Ling;Yu, Haiwu;Wang, Xiaojie
为了了解蝾螈足垫的湿附着力，我们首先在三种不同的润湿条件下测试和评估蝾螈的附着和攀爬能力。利用扫描电子显微镜对蝾螈足垫的微结构进行了表征。通过观察蝾螈足垫的微纳米结构特征，设计并在PDMS上制备了四种不同的微图案，包括圆形柱、六边形柱以及闭合和半闭合六边形脊的两种混合图案。分别用多功能表面仪和附着力测试仪测量了微结构表面的静摩擦力和附着力。实验研究了微图案对静摩擦力的影响，以及回缩速度、液体量、接近回缩周期对附着力的影响。结果表明，大量的液体降低粘附和摩擦，但少量的液体增加粘附和摩擦。结果发现，存在一个最佳量的液体（约0.1 μ l），可以提高粘附。我们的研究结果可以提供洞察的重复剪切运动的蝾螈的足垫在流的条件下，以及可能的功能，密集的纳米柱阵列上的蝾螈足垫。
To understand wet adhesion of newt foot pads, we firstly examined and evaluated the attachment and climbing abilities of newts under three different wetting conditions. Then we characterized the micro and nanostructures of newts' foot pads by using the scanning electron microscopy. Followed by observing the micro and nanoscale structural features of newts' foot pads, four different micropatterns, including round pillars, hexagonal pillars, and two hybrid patterns with closed and semi-closed hexagonal ridges, were designed and fabricated on PDMS. The static friction and adhesion of microstructured surfaces were measured by using a multi-functional surface meter and an adhesion testing equipment, respectively. Effects of micropattern on static friction, and effects of retraction speed, amount of liquid, approach-retraction cycle on adhesion were investigated experimentally. Results suggested that a larger amount of liquid decreases the adhesion and friction, but a little liquid increases the adhesion and friction. It was found that there exists an optimum amount of liquid (about 0.1 mu l) that can enhance the adhesion. Our results can give insights into the repeated shear movements of a newt's foot pads in the stream condition as well as the possible functions of dense nanopillar arrays on newt foot pads.