The Ultrasonic Wave-Assisted Preparation and Modification by KH-550 of SiO<sub>2</sub> Aerogels

Under ultrasonic wave and using aminopropyltriethoxysilane as modifier and acid catalyst, hydrophobic SiO 2 aerogel was prepared through fractional hydrophobic modification and ambient pressure drying of the raw material, tetraethoxysilane (TEOS), in the process of sol-gel and acid-base catalysis.SiO 2 aerogels were analyzed and compared using scanning electron microscopy, Brunauer-Emmett-Teller analysis method, Fourier transform infrared spectroscopy. The results indicate that modifiering by the ultrasonic wave and aminopropyltriethoxysilane, the temperature tolerance of the SiO 2 aerogels was 407°C.the specific surface area of the SiO 2 aerogels was 877.17m 2 /g. Pore distribution in micro -pore range was 0.5～1nm. Pore distribution in meso -pore range was 1.8～2.5nm. Thermal stability of the hydrophobic SiO 2 aerogels prepared through fractional modification assisted by the ultrasonic wave method was increased with the hydrophobic angle at160°, which showed super hydrophobicity.