Claims
- 1. In a silica organosol consisting of silica dispersed in a water-miscible organic solvent, a process for treating the silica with a trialkoxysilane to make the silica more organophilic while minimizing the self condensation of the trialkoxysilane, which process comprises:
- (a) admixing water and a catalytic amount of acid with the silica organosol; and
- (b) gradually adding a trialkoxysilane to the admixture under reactive conditions; and
- (c) removing substantially all of the water;
- wherein the trialkoxysilane is present at a level up to about 30% by weight based upon the weight of the silica and the water is added at an amount up to about 15% by weight based upon the weight of the water-miscible organic solvent.
- 2. The process of claim 1 further characterized in that the silica is a colloidal silica.
- 3. The process of claim 1 further characterized in that the water is removed by azeotropic distillation.
- 4. The process of claim 1 further characterized in that the trialkoxysilane is present at a level of up to about 20% by weight based upon the weight of the silica.
- 5. The process of claim 4 further characterized in that the trialkoxysilane is present at a level of from about 5 to about 12% by weight based upon the weight of the silica.
- 6. The process of claim 1 further characterized in that the water is present in an amount ranging from about 1 to about 10% by weight based upon the weight of the water-miscible organic solvent.
- 7. The process of claim 1 further characterized in that the trialkoxy silane is gradually added to the admixture of water, acid and silica organosol while the admixture is maintained at a temperature ranging from about 25.degree. to about 140.degree. C.
- 8. The process of claim 7 further characterized in that the admixture is maintained at a temperature ranging from about 90.degree. to about 120.degree. C.
- 9. A surface treated silica prepared by the process of claim 1.
Parent Case Info
This application is a continuation of U.S. Ser. No. 629,644, filed July 11, 1984, now abandoned.
US Referenced Citations (28)
Foreign Referenced Citations (1)
Number |
Date |
Country |
WO8202403 |
Jul 1982 |
WOX |
Non-Patent Literature Citations (4)
Entry |
Surface and Colloid Science, vol. 6, 1973, Egon Matijevic, pp. 74-79. |
Chem Abstracts, 97:57221e, Inagaki et al. |
Chem Abstracts, 90:105220h, Arakawa et al. |
Chem Abstracts, 92:23635z, Suzuki et al. |
Continuations (1)
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Number |
Date |
Country |
Parent |
629644 |
Jul 1984 |
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