自然界中的蓮花葉面具有超疏水之特性，其接觸角約150°、滑動角約5°。其表面具能防水、自潔和流體滑動於界面之能力，可應用於玻璃清潔、太陽能電池、浴室及交通工具之清潔。基於仿生學建立超疏水表面之結構，在近幾年引發極廣泛的基礎應用研究。然而該凸柱狀結構之結構強度低、大量複製困難，並易受外力受損失去自潔性的缺點。
本研究在於設計與分析創新微米級微結構，相對於凸柱狀之蓮花結構，提出一種多層次半封閉微結構，其封閉處可困住空氣，產生超疏水性之機制包括回復力、基材彈性與封閉性之空氣彈簧。此半封閉性之反蓮花結構，其接觸角可達168°、滑動角約於5°，水滴可於微結構表面反彈。但是在實際應用上，若表面受到油脂汙染其超疏水性也會遭受破壞，故製作出具疏水及疏油性之表面是相當重要的。實驗主要利用特殊塗料來改變PDMS表面特性並探討此結構之疏水特性及疏油特性，也從實際應用上討論其潛力與可行性。

In this study, we show an innovative novel super-hydrophobic micro-structure. Opposite to the pillar lotus structure, the structure is multi-leveled concaved with trapped air. The mechanisms for waterproof include the restoring force, the elastic deformation of the structure and the air spring force resulting from the concaved structure with trapped air. The semi-mural micro-structure of negative lotus structure has the following characteristics which the contact angle is 168°, sliding angle is about 5°.In fact, the super-hydrophobicity of the surface will be destroyed by oil pollution. It is important that fabricating a surface with both super-hydrophobic and super-oleophobic functions. The experiment use special coating to change the characteristics of PDMS surface and proof the super-hydrophobicity and super-oleophobicity of this surface. Also, we discuss its potential and feasibility in the practical applications.

Keywords: Lotus effect, Contact angle, PDMS, Super-hydrophobicity, oleophobicity, Air spring.

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