由於其廣泛的應用性，超疏水和超親水材料在研究領域上一直是熱門的選擇，於材料表面製備微陣列並透過接觸角的分析，可以了解並透過特定參數去轉換表面的親疏水程度。本研究利用CNC微鑽法及光微影製程，製備出不同尺寸的微柱陣列模具，透過PDMS翻模，在具有圓柱陣列的PDMS表面上塗佈PNIPAM，以探討其熱敏性表現與微柱結構的關係。
研究結果顯示，PNIPAM的濃度對熱敏性表現影響不大，且接觸角會隨著時間變化，因此在測量上會固定一時間為比較基準。相對於平板熱敏性表面而言，有微柱陣列的熱敏性表面在其臨界溫度LCST上下可以提高接觸角的差值。當圓柱直徑為200 μm、間距為50 μm、高度為200 μm，可以得到最大的接觸角差值88°。

Superhydrophobic and superhydrophilic surfaces have been used in various applications. To fabricate the surface with both properties via temperature control, in this study, PDMS with a micro-pillar array was constructed, followed by being coated with thermoresponsive polymer, PNIPAM. The contact angle change between the temperature below and above LCST was examined.
The results showed that the concentration of PNIPAM has little effect on the thermoresponsive behavior when it was coated on the flat surface. In addition, the wetting model of PNIPAM above its LCST was Wenzel's state like. As for the polymer coating method, the performance of PNIPAM on the micropillared surface prepared by spin coating method was better than casting. Compared with a flat thermoresponsive polymer surface, the contact angle difference above and below its critical temperature (LCST) was increased for the thermoresponsive polymer surface with the micro-pillar array increased. The maximum contact angle difference of 88° was obtained for the PDMS surface with micro-pillars having 200 μm in diameter, 50 μm in spacing, and 200 μm in height.

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