Low molecular weight aromatic compounds possessing nonflammable and flammable characteristics in calcium fluoride nanocomposite matrices after calcination at 800 °C

Calcium chloride reacted with potassium fluoride in the presence of low molecular weight aromatic compounds ( ArH ) such as bisphenol AF, bisphenol A, bisphenol F, biphenyl, and 1-(2-naphthyl)ethanol under alkaline conditions to afford new calcium fluoride/ ArH composites. Dynamic light scattering and field emission scanning electron micrographs measurements show that these calcium fluoride/ ArH composites are nanometer size-controlled fine particles and have a good dispersibility and stability in water, tetrahydrofuran, 1,2-dichloroethane, methanol, dimethyl sulfoxide, N , N -dimethylformamide, and 2-propanol. Interestingly, aromatic compounds possessing acidic hydroxyl groups in the calcium fluoride nanocomposites were found to exhibit a nonflammable characteristic even after calcination at 800 °C, although the corresponding aromatic compounds possessing neither acidic hydroxyl groups nor hydroxyl groups in the nanocomposites exhibited a usual flammable characteristic under similar conditions. In contrast, calcium fluoride/ ArH nanocomposites, which were prepared under no catalytic conditions, afforded a clear weight loss corresponding to the contents of ArH in the composites to exhibit a usual flammable characteristic. Figure Ar-OH can exhibit a nonflammable characteristic in calcium fluoride nanocomposite matrices even after calcination at 800°C