Abstract
A study was made on the hydrophobic modification of γ-alumina and boehmite powders with isopropyl triisostearyl titanate (TTS). The TTS treatment was performed by dipping 10g of each powder in 200ml of TTS benzene solution for described time. The powders showed hydrophobic properties and thus floated on water, as a result of treating them with TTS solutions of over 1×10-2mol/l concentration for γ-alumina and of over 1×10-3mol/l concentration for boehmite. Dipping was enough for 15 minutes. In hydrophobing of the powders, the de-alkoxylation reaction between TTS and the surface hydroxyl groups of the powders takes place as -OH→-O-Ti-(OCO(CH2)14 CH (CH3)2)3. It was presumed that the number of reacted surface hydroxyl groups was about 4% of the number of surface hydroxyl groups.
