Publication Date:
2013-10-07
Description:
Perfluoro-2-methyl-3-oxahexanoic acid/silica nanocomposites [R F -CO 2 H/SiO 2 ] were prepared by the sol–gel reaction of tetraethoxysilane in the presence of silica nanoparticles and the corresponding fluorinated carboxylic acid under alkaline conditions. R F -CO 2 H/SiO 2 nanocomposites were found to exhibit no weight loss in proportion to the contents of fluorinated carboxylic acid in the composites even after calcination at 800 °C. The modified glass surface treated with the R F -CO 2 H/SiO 2 nanocomposites was shown to give a good oleophobicity with superhydrophilicity imparted by fluorinated carboxylic acid in the composites. R F -CO 2 H/SiO 2 nanocomposites were also applied to the encapsulation of a variety of low molecular weight aromatic and aliphatic compounds such as bisphenol AF [BPAF], bisphenol A [BPA], 4,4′-biphenol [BPOH], octafluoro-4,4′-biphenol [FBPOH], 4,4′-bis(triethoxysilyl)-1,1′-biphenyl [BTSBP], 3-(trihydroxysilyl)propane-1-sulfonic acid [THSP], α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), and γ-cyclodextrin (γ-CD). Encapsulated aromatic compounds possessing acidic hydroxyl groups such as BPAF, BPA, and FBPOH in the R F -COOH/SiO 2 nanocomposites were found to exhibit no weight loss corresponding to the contents of aromatic compounds in the composites even after calcination at 800 °C. On the other hand, encapsulated aromatic compounds possessing no acidic hydroxyl groups such as BTSBP and aliphatic compounds (THSP, α-, β-, and γ-CD) gave a clear weight loss corresponding to the contents of these compounds in the composites after calcination. In addition, the fluorinated silica nanocomposite-encapsulated these compounds were applied to the surface modification of glass to exhibit a good oleophobicity with superhydrophilicity imparted by fluorinated carboxylic acid on the surface. Figure ᅟ
Print ISSN:
0303-402X
Electronic ISSN:
1435-1536
Topics:
Chemistry and Pharmacology
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Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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