超疏水(或蓮花效應)是大家熟知且廣泛研究的一項課題，其形成的原因主要是表面具有由適當官能基組成或修飾的微米及奈米結構。由於超疏水表面具有大接觸角與極小滑落角之特性(或自潔能力)，也被應用在日常生活許多方面上，如玻璃及雨具等。
目前製造超疏水表面的方法及材料有許多，本研究提出利用氣-液與液-液溶膠-凝膠法反應兩種方式在PDMS與玻璃基板上製備超疏水表面。有關氣-液溶膠-凝膠法反應，本研究係以旋轉塗佈方式將反應物塗佈在高分子PDMS表面，使PDMS膨潤後，藉由氣相催化劑的擴散，在PDMS表層與內部同時反應產生SiO2粒子。而利用液-液相溶膠-凝膠法反應，則是透過潤浸塗佈(dip coating)方式將基材(PDMS與玻璃)置於含有粒子之溶膠-凝膠溶液，使SiO2粒子附著於基板表面。
由實驗結果顯示，以氣-液溶膠-凝膠法反應所得到的SiO2粒子可以鑲嵌於PDMS基材表面，再經由silane改質過後表面產生皺褶狀結構，進而得到一接觸角160˚之超疏水表面；而以液-液相溶膠-凝膠法反應經潤浸塗佈方式得到的表面，不需再經過改質便可得到一水滴完全無法沾附的超疏水表面，此外，我們藉由降低潤浸塗佈速度與降低粒子在溶液中的分散密度，可得到較透光之表面。

Superhydrophobicity (or the lotus effect), a well-known phenomenon and widely studied research topic, results from a surface having the micro/nanostructures composed of either proper and/or being modified functional groups. Owing to its larger contact angle (>150o) and smaller sliding angle (<10o) (or self-cleaning), superhydrophobicity has been found in many applications such as rain coat, window and so on.
There are numerous methods to construct superhydrophobic surface. In this study, we proposed the gas-liquid phase sol-gel process and utilized the liquid-liquid phase sol-gel process to construct superhydrophobic surface on polydimethyl siloxane (PDMS) and/or glass substrates. For the gas-liquid phase sol-gel process, the reactant was spin-coated on the PDMS substrate, followed by the diffusion of the vapours of the reactant and catalyst into the PDMS substrate. For the liquid-liquid phase sol-gel process, the generated hydrophobic SiO2 particles were deposited on the PDMS and glass substrates through dip coating. The results show that the SiO2 particles are formed and inlaid in the PDMS surface via the gas-liquid phase sol-gel process. Two layers of SiO2 particles are prepared and the wrinkle-like structures are obtained on the 2nd layer of SiO2 particles after silane modification. The contact angle of the surface as constructed is approximately 160o. As to the liquid-liquid phase sol-gel process, there is no need for further modification of the surface and the water droplet will not stay on the surface. By lowering the dip coating speed and concentration of the particles in the solution, a translucent superhydrophobic surface can be obtained.

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