SILANIZED SILICA

摘要

The present invention provides a silanized pyrogenically- produced silica with the following physico-chemical properties: Specific surface area m2/g 80 - 400 Primary particle size nm 7 - 40 Tamped density g/l 50 - 300 pH value 3 - 10 Carbon content % 0.1 - 15 DBP number % < 200. The invention also provides a method of producing the above silanized pyrogenically-produced silica, comprising spraying pyrogenically-produced silica in a mixing container under intensive mixing, first with water or dilute acid and then with hexamethyldisilazane, mixing for 15 to 30 minutes, and tempering at a temperature of 100 to 400.degree.C for a period of 1 to 6 h.