The Ultrasonic Wave-Assisted Preparation and Modification by KH-550 of SiO2 Aerogels

Abstract

Under ultrasonic wave and using aminopropyltriethoxysilane as modifier and acid catalyst, hydrophobic SiO2aerogel 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.SiO2aerogels 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 SiO2aerogels was 407°C.the specific surface area of the SiO2aerogels was 877.17m2/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 SiO2aerogels prepared through fractional modification assisted by the ultrasonic wave method was increased with the hydrophobic angle at160°, which showed super hydrophobicity.