Claims
- 1. The method of altering the hydrophobicity of particulate silica comprising treating the silica with an organosilane in varying amounts in order to chemically bond the organosilane to the surface of the particulate silica, the organosilane having the general formula selected from the group consisting of ##STR10## wherein, in each formula, R is an alkyl radical of 1 to 4 carbon atoms or hydrogen;
- a has a value of 0, 1 or 2;
- R' is a methyl or ethyl radical;
- R" is an alkylene group of 1 to 4 carbon atoms;
- R'" and R"" are each independently selected from the group consisting of alkyl radicals of 1 to 18 carbon atoms, --CH.sub.2 C.sub.6 H.sub.5, --CH.sub.2 CH.sub.2 OH, --CH.sub.2 OH, and --(CH.sub.2).sub.x NHC(O)R.sup.vi, wherein x has a value of from 2 to 10 and R.sup.vi is a perfluoroalkyl radical having from 1 to 12 carbon atoms;
- R.sup.v is selected from the group consisting of alkyl radicals of 16 or 18 carbon atoms, --CH.sub.2 C.sub.6 H.sub.5, --CH.sub.2 CH.sub.2 OH, --CH.sub.2 OH, and --(CH.sub.2).sub.x NHC(O)R.sup.vi, wherein x has a value of from 2 to 10 and R.sup.vi is a perfluoroalkyl radical having from 1 to 12 carbon atoms; and
- X is chloride, bromide, fluoride, iodide, acetate or tosylate.
- 2. The method of claim 1 wherein the organosilane is 3-(trimethoxysilyl)propyl dimethyloctadecyl ammonium chloride.
- 3. The method of claim 1 in which the organosilane is present in an amount sufficient to provide a hydrophilic silica.
- 4. The method of claim 1 in which the organosilane is present in an amount sufficient to provide a hydrophobic silica.
- 5. The method of claim 1 in which the treatment is conducted in an aqueous solvent.
- 6. The method of claim 1 in which the treatment is conducted in a non-aqueous solvent.
- 7. The method of claim 1 wherein R.sup.v is an alkyl radical of sixteen carbon atoms.
- 8. The method of claim 1 wherein R.sup.v is an alkyl radical of eighteen carbon atoms.
- 9. The method of claim 2 wherein the antimicrobial agent has the formula ##STR11##
- 10. A method of destabilizing foams produced by surfactants in a foaming liquid comprising adding to the liquid a particulate material having an organosilane chemically bonded to the surface of the particulate, the organosilane having the general formula selected from the group consisting of ##STR12## wherein, in each formula, R is an alkyl radical of 1 to 4 carbon atoms or hydrogen;
- a has a value of 0, 1 or 2;
- R' is a methyl or ethyl radical;
- R" is an alkylene group of 1 to 4 carbon atoms;
- R'" and R"" are each independently selected from the group consisting of alkyl radicals of 1 to 18 carbon atoms, --CH.sub.2 C.sub.6 H.sub.5, --CH.sub.2 CH.sub.2 OH, --CH.sub.2 OH, and --(CH.sub.2).sub.x NHC(O)R.sup.vi, wherein x has a value of from 2 to 10 and R.sup.vi is a perfluoroalkyl radical having from 1 to 12 carbon atoms;
- R.sup.v is selected from the group consisting of alkyl radicals of 16 or 18 carbon atoms, --CH.sub.2 C.sub.6 H.sub.5, --CH.sub.2 CH.sub.2 OH, --CH.sub.2 OH, and --(CH.sub.2).sub.x NHC(O)R.sup.vi, wherein x has a value of from 2 to 10 and R.sup.vi is a perfluoroalkyl radical having from 1 to 12 carbon atoms; and
- X is chloride, bromide, fluoride, iodide, acetate or tosylate.
- 11. The method of claim 10 wherein the organosilane is 3-(trimethoxysilyl)propyl dimethyloctadecyl ammonium chloride.
- 12. The method of claim 10 in which the organosilane is present in an amount sufficient to provide a hydrophilic particulate.
- 13. The method of claim 10 in which the organosilane is present in an amount sufficient to provide a hydrophobic particulate.
- 14. The method of claim 12 wherein the weight ratio of the organosilane to the particulate material is between 0.1 to less than 0.25.
- 15. The method of claim 13 wherein the weight ratio of the organosilane to the particulate material is at least 0.25.
- 16. The method of claim 10 wherein R.sup.v is an alkyl radical of sixteen carbon atoms.
- 17. The method of claim 10 wherein R.sup.v is an alkyl radical of eighteen carbon atoms.
RELATED PATENT APPLICATIONS
This application is a division of application Ser. No. 378,563 filed Jul. 7, 1989, now U.S. Pat. No. 5,073,298, which is a continuation-in-part of application U.S. Ser. No. 07/221,581, filed Jul. 20, 1988, now abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4395352 |
Kulkarni et al. |
Jul 1983 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
378563 |
Jul 1989 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
221581 |
Jul 1988 |
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