丙二醇單甲醚乙酸酯為溶劑合成二氧化矽奈米粒子溶膠及其混成薄膜的製備與分析

本研究用丙二醇單甲醚乙酸酯(PGMEA)作為溶劑，使用溶膠-凝膠法將四乙氧基矽烷(TEOS)水解縮合合成出二氧化矽奈米粒子後，加入3-(三甲氧基矽烷基)丙基甲基丙烯酸酯(MSMA)作為偶合劑進行表面改質，透過偶合劑分子兩端的有機和無機官能基，可使無機二氧化矽分子與有機高分子結合。將改質後的二氧化矽奈米粒子溶膠和多官能基壓克力單體 DPHA 混和後透過旋轉塗佈、紫外光硬化等技術製作單層有機-無機混成薄膜，接著比較在不同溶劑(IPA、PGMEA)下，觀察合成出來的膜的型態與性質。以 PGMEA 為溶劑時，薄膜的厚度和粗糙度皆小於以 IPA 為溶劑製備的薄膜。在測量熟化 120 天二氧化矽溶膠，IPA 為溶劑的粒徑約為 35.5 nm，而 PGMEA 為溶劑的粒徑約為 22.3 nm。除了熟化 50 天以上，以 IPA 為溶劑的溶膠製備的混合薄膜外，所有製備的混合薄膜都是高度透明的。這表示 PGMEA 比 IPA 更適合作為合成二氧化矽奈米粒子和製備混成薄膜的溶劑。二氧化矽混成薄膜的厚度(h)對固成分(c)及旋轉塗佈轉速(ω)之關係符合 h=Ac^α ω^(-β) 之經驗式。以 IPA 為溶劑之溶膠塗佈液，α 值在 β 值不同轉速及固成分下變動不大，平均分別在 1.17 跟 0.46；以 PGMEA 為溶劑之溶膠塗佈液，α值在 β 值不同轉速及固成分下也變動不大，平均分別在 1.68 跟 0.53。針對熟化時間發現， α 值隨著熟化天數增加而略增。

關鍵字

溶膠-凝膠法；二氧化矽奈米粒子；旋轉塗佈；薄膜厚度；丙二醇單甲醚乙酸酯

並列摘要

In this study, PGMEA was used as the solvent to synthesize silica nanoparticles by a sol-gel method of hydrolysis and condensation of tetraethoxysilane (TEOS), and then 3-(trimethoxysilyl)propyl acrylate (MSMA) was added as the coupling agent for surface modification of the nanoparticle. Through the organic and inorganic functional groups at the two ends of the coupling agent molecule, the inorganic silica can be combined with organic polymer. After mixing silica sol, multifunctional acrylic monomer, and photoinitiator, organic-inorganic hybrid thin films were prepared on plastic substrates or silicon wafers by spin coating and UV curing. Different solvent (IPA or PGMEA) was used to understand the morphology and properties of the prepared thin films. When PGMEA was used as the solvent, both the thickness and the roughness of the thin film were less than those of the thin film prepared by using IPA as the solvent. The particle size of the silica in the IPA sol was about 35.5 nm after aging 120 days while that in the PGMEA sol was about 22.3 nm. All the prepared hybrid thin films were highly transparent except for that prepared from the IPA sol aged for more than 50 days. It means that PGMEA is more suitable than IPA as the solvent to synthesize silica nanoparticles and prepare hybrid thin films. The relationship between the film thickness (h) and the spin rate (ω) or the solid content (c) can be conformed to the formula: h=Ac^α ω^(-β). For the IPA coating solutions, the average α and β values were 1.17 and 0.46, respectively. For the PGMEA coating solutions, the average α and β values were 1.68 and 0.53, respectively. It was found that the α values increased slightly with the increase of the aging days of the sol.