Amorphous low molecular weight aromatic compounds possessing no weight loss behavior in fluoroalkyl end-capped vinyltrimethoxysilane oligomeric silica/hexagonal boron nitride nanocomposites even after calcination at 800°C

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Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(CH2CHSi(OMe)3)n-RF; n = 2, 3; RF = CF(CF3)OC3F7] undergoes the sol–gel reactions in the presence of hexagonal boron nitride (h-BN) nanoparticles and low molecular weight aromatic compounds (ArHs) such as bisphenol AF (BPAF) and 1-(2-naphthyl)ethanol (Naph-EtOH) under alkaline conditions at room temperature to afford the corresponding fluorinated oligomeric silica/h-BN/ArHs nanocomposites [RF-(VM-SiO3/2)n-RF/h-BN/ArHs]. TG–DTA analyses and XRD spectra measurements show that the encapsulated ArHs in the fluorinated oligomeric silica/h-BN nanocomposites exhibit an amorphous structure, affording no weight loss corresponding to the contents of the ArHs in the nanocomposites even after calcination at 800°C, although the simple blend hybrids of the RF-(VM-SiO3/2)n-RF/h-BN nanocomposites and the original ArHs provide not only the crystal characteristic toward the ArHs but also a clear weight loss behavior in proportion to the contents of the ArHs in the blend hybrids after calcination at 800°C. 1H MAS NMR spectra, UV–Vis spectra, and fluorescent spectra of the RF-(VM-SiO2)n-RF/h-BN/ArHs nanocomposites obtained through the sol–gel reactions under alkaline conditions showed the presence of the ArHs in the nanocomposites, respectively.