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Fluoroalkyl end-capped acrylic acid oligomer [R F-(ACA) n-R F ]/hexagonal boron nitride (h-BN) nanocomposites [R F-(ACA) n-R F /h-BN] were prepared by reaction of the corresponding oligomer with h-BN nanoparticles (mean diameter: 50 nm) under non-catalytic or alkaline conditions, respectively.

Fluoroalkyl end-capped vinyltrimethoxysilane oligomer/anatase titanium oxide nanocomposite-encapsulated low molecular weight aromatic compounds [R F -(VM-SiO 2 ) n -R F /an-TiO 2 /Ar-H] were prepared by the sol-gel reactions of the corresponding oligomer in the presence of anatase titanium oxide nanoparticles (an-TiO 2 ) and the aromatic compounds such as bisphenol A [BPA], 1,1′-bi(2-naphthol) [BINOL], and fullerene under alkaline conditions. Thermogravimetric analyses measurements show that R F -(VM-SiO 2 ) n -R F /an-TiO 2 nanocomposite-encapsulated BPA and BINOL, in which the theoretical contents in the composites are 25∼32 %, were found to give no weight loss corresponding to the contents of these aromatic compounds even after calcination at 800°C. On the other hand, the corresponding nanocomposite-encapsulated fullerene exhibited weight loss behavior related to the presence of fullerene under similar conditions; however, UV-vis spectra showed the presence of the residual fullerene in the composites even after calcination. An-TiO 2 in these fluorinated nanocomposites can keep its crystalline structure without phase transformation into rutile even after calcination at 1,000°C, although the parent an-TiO 2 nanoparticles underwent a complete phase transformation into rutile under similar conditions. Notably, R F -(VM-SiO 2 ) n -R F /an-TiO 2 /Ar-H nanocomposites can give a good photocatalytic activity even after calcination at 1,000°C for the decolorization of methylene blue under UV light irradiation. More interestingly, these fluorinated nanocomposites before and after calcination were found to exhibit a higher photocatalytic activity at the initial UV light irradiation from 1 to 3 min than that of the corresponding R F -(VM-SiO 2 ) n -R F /an-TiO 2 nanocomposites under similar conditions.