| 摘要: | 本研究中，將奈米氧化鋯結晶粉體進行雙重改質，使可以分散於極性範圍相當大的各種有機溶劑中，並以之與不同壓克力單體混合製作出高折射率之透明光學材料。以往本實驗室大於4個碳的單一有機酸進行奈米氧化鋯改質，僅能分散在非極性溶劑（如苯，甲苯等）中。而醋酸螯合之氧化鋯則幾乎完全不分散。本次研究中，我們將已經用有機酸(乙酸、丁酸、甲基壓克力酸)改質之粉體，再以壓克力基之矽烷(3-(trimethoxysilyl) propylmethacrylate, MPTS) 進行雙重表面改質。透過此一作法可擴大粉體與更多溶劑相容。透過Hansen溶度參數（HSP）以30種溶劑來歸納其分散性質。我們並利用熱重分析(TGA)，液態和固態核磁共振(NMR)分析，透過合理的計算法，可估算此兩種改質劑在奈米氧化鋯表面分別的螯合量。
經過不同有機酸與矽烷的配比，改質後奈米粉體除可同時分散於極性-非極性的溶劑，更可分散於甲基丙烯酸(MMA)、苯乙烯(styrene)與數種壓克力樹酯單體。其中含有乙酸及甲基壓克力酸之兩種粉體(ZAS，ZMS)，可直接分散於含有苯基之高折射壓克力單官能機單體PHEA(2-Phenoxy ethyl acryate, EM210,折射率硬化前1.51,硬化後1.53)或雙官能機單體 TMPTA (Trimethylolpropane triacrylate, EM231,折射率硬化前1.47,硬化後1.49)，達到高無機含量(55~60 wt. %)之完全無溶劑塗料。因為塗料之黏度隨氧化鋯添加量迅速增加。假若要獲得更多的無機含量，就必須借助溶劑來降低黏度。研究中又發現不論是單官能機或雙官能機的單體，若只添加單一原料，所得到之複合材料塗佈固化後，會產生折射率梯度，於低粉體添加量下更為明顯。研究中又發現不論是單官能基、三官能基的單體或混合不同單體做為混合樹酯，於低濃度下仍會得到折射率不均勻的厚膜。最終我們以商用高折射率之壓克力配方HG147(折射率硬化前1.58,硬化後1.61)並在有溶劑幫助的條件下混合約82.3 wt% 之ZMS，則可製作出折射率1.725的均勻厚膜。
Redispersible nanoparticle treated with dual modifiers in a broad range of solvents is a notable achievement in this work. We reported the dispersion behavior of zirconia nanoparticle by mixing grafted with one specific carboxylic acid and 3-(trimethoxysilyl)propylmethacrylate (MPTS). This is a major improvement compared to that modified with carboxylic acid along, and enable the blending with acrylate monomers. In previous works of our lab, nanoparticles grafted with single carboxylic acid with more than 4 carbons could only be dispersed in non-polar solvents such as benzene, toluene, while that modified with acetic acid could not be dispersed in any organic solvent. After further modifying with MPTS, it became dispersible in both polar and non-polar solvents. In test of fillers in 30 common solvents with Hansen solubility parameters (HSP), it was found that the compatible solvents can be represented better with two spheres in the HSP space than just a single sphere, as done in the original HSP theory.
This study reported three kinds of dual modifier nano-zirconia, respectively, to distinguish between organic acids: acetic acid / MPTS (ZAS), butyric acid / MPTS (ZBS), acrylic acid / MPTS (ZMS), these powders appearing a wide range of organic solvent dispersion (polar - non-polar), and the number of species dispersible resin monomers was special, such as: methyl methacrylate (MMA), styrene (styrene) and acrylic monomers, and ZAS and ZMS dispersed in PHEA (EM210) with high content (55 ~ 60 wt.%), but we couldn’t obtain uniform film without index gradient at low zirconia content . Finally, we use commercially sol HG147 with ZMS (82.3 wt.%) in EA, the highest refractive index 1.725 thick film obtained. |
