Patent ID: 9120928
Filing Date: 2015-09-01
Classification: B82Y,C01P,C09C

Abstract:
1. A method for preparing silica modified by a silane coupling agent, comprising: (a) adding water to an organic solvent; (b) adjusting pH value of the mixture of step (a) to either below 6 by adding an acid or over 8 by an alkali; (c) adding the coupling agent to the mixture of step (b), wherein the molar ratio of the coupling agent to water is in the range of 1:0.1-1:10000; (d) letting the mixture of step (c) stand for 0.5-48 h, whereby a stabilized sol solution of the coupling agent is formed; (e) adding silica to the sol solution to produce precipitated silica in an amount less than 10 g/ml and fumed silica in an amount less than 1 g/ml, g/ml being a mass to volume ratio of the silica to the so solution; (f) dispersing the silica fully into the sol solution to make a uniformly-dispersed turbid solution by one of the following dispersing methods: (g) stirring and evaporating the uniformly-dispersed turbid solution at room temperature to produce a mixture having a weight that is 0.1%-50% of the weight of the turbid solution of step (f); (h) heating a stirring the mixture of step (g) at 50-80° C. for 0.5-120 h and then at 81-260° C. for 0.5-48 h; and (i) drying and crushing the mixture of step (h), wherein each of steps (a)-(g) and (l) is carried out, at a temperature less than 50° C., whereby, silica modified by the coupling agent is obtained.