本研究將二氧化矽奈米球以單層形式製備於常見的高分子聚合物,分別為聚苯乙烯(PS)、聚對苯二甲酸乙酯(PET),利用CF4電漿進行表面改質,使用CA、FE-SEM、XPS、UV-vis等儀器分析並探討疏水疏油性質、表面物理結構、表面化學組成及透光度之變化,搭配OES分析電漿中物種濃度之變化。 改變操作壓力對表面製備單層奈米球的聚苯乙烯膜材(PS-sphere)進行表面改質,發現操作壓力低時疏水性質較佳(~155°)、蝕刻速率快且奈米柱較易形成,也發現保有奈米柱之膜材透光性質較佳。改變電漿功率發現各功率下PS-sphere皆能達到超疏水、疏油表面,發現電漿功率較低(50 W)時 ,有較佳的表面自潔效果,且膜材保有良好透光性。 電漿改質PS-sphere探討出最適化電漿參數,將PS、PET及PET-sphere進行改質,發現表面製備奈米球的膜材有助於提升疏水性質,且氟碳比皆比未製備奈米球膜材更高,PET-sphere膜材雖然形成奈米柱結構但未達超疏水之標準,由XPS發現原因為氟碳比略低,且氧碳比偏高。 沉積C2H2F4疏水薄膜於表面有奈米柱結構之PET膜材(PET-pillar),疏水性質即大幅提升(~169°),氟碳比大幅上升,且氧碳比大幅下降,沉積後奈米球及奈米柱仍近似原來的表面型態,透光度比原始PET略下降10~20%,仍保有良好透光性質。
In this study, polystyrene and PET polymers covered with silica nanospheres in the form of monolayer were modified by CF4 plasma to form nanostructured surface. The plasma diagnostics (OES) and surface analysis (CA, FE-SEM, XPS, UV-vis) were used to elucidate the process-structure-property relationship. The results revealed that super-hydrophobic surface with water contact angle of 155° were achieved on polystyrene polymers. The surface consisted of nano-pillars of about 300 nm in height and 100 nm in diameter, and the fluorine-to-carbon atomic ratio was about 0.8. The surface was also oleophobic as the CH2I2 contact angle reached 110°. Moreover, the surface exhibited good self-cleaning effect and visible light transmittance. Due to its high oxygen content in the pristine PET polymer, the CF4 plasma modified PET surface was not super-hydrophobic. Although nano-pillars were formed on PET surface, but its fluorine-to-carbon ratio was lower and oxygen-to-carbon ratio was higher than the plasma modified polystyrene. Therefore, a thin layer of fluorocarbon film of about 30 nm was deposited on CF4 plasma modified PET surface. Consequently, the surface hydrophobicity (~169°) and fluorine-to-carbon ratio (1) was increased dramatically and oxygen-to-carbon ratio was significantly decreased. The modified PET surface exhibited excellent self-cleaning effect since the WCA hysteresis was about 5° and the sliding angle was less than 8° in dynamic contact angle analysis.