Claims
- 1. A method for improving the stability of a mixture comprising carbonyl iron powder and a silicone resin containing SiO.sub.4/2 siloxane units and SiOH sites, said method comprising mixing a viscosity-stabilizing amount of an halosilane with said mixture.
- 2. A method according to claim 1 wherein the silicone resin is a liquid silicone resin containing SiO.sub.4/2 siloxane units, SiH sites and SiOH sites which has been prepared by
- (A) forming an acidic homogeneous mixture comprising
- (a) an organic solvent solution of from 40 to 60 parts by weight of a resinous copolymeric siloxane containing silicon-bonded hydroxyl radicals and consisting essentially of (CH.sub.3).sub.3 SiO.sub.1/2 siloxane units and SiO.sub.4/2 siloxane units wherein the ratio of the former to the latter, on a molar basis, has a value of from 0.6/1 to 0.9/1, and
- (b) 40 to 60 parts by weight of a methylhydrogenpolysiloxane having the formula Me.sub.3 SiO(Me.sub.2 SiO).sub.x SiMe.sub.3 wherein Me denotes the methyl radical and x has a value of from 35 to 70; and
- (B) heating the homogenous mixture to remove substantially all of the organic solvent therefrom; and the halosilane is a chlorosilane.
- 3. A method according to claim 2 wherein the chlorosilane has the formula R.sub.3 SiCl, wherein R denotes a monovalent hydrocarbon radical having 1 to 6 carbon atoms, which is mixed in an amount equal to from about 0.1 to 0.4 millimols per 100 parts by weight of the basic carbonyl iron powder.
- 4. A method according to claim 3 wherein the chlorosilane is vinyldimethylchlorosilane.
- 5. A method according to claim 3 wherein the mixture is vacuumed at a temperature of up to 100.degree. C. before the chlorosilane is mixed therewith.
- 6. A method according to claim 5 wherein the chlorosilane is vinyldimethylchlorosilane.
- 7. A method according to claim 3 wherein the mixture is vacuumed at ambient temperature before the chlorosilane is mixed therewith.
- 8. A method according to claim 7 wherein the chlorosilane is vinyldimethylchlorosilane.
- 9. The composition produced by the method of claim 1.
- 10. The composition produced by the method of claim 2.
- 11. The composition produced by the method of claim 3.
- 12. The composition produced by the method of claim 4.
- 13. The composition produced by the method of claim 5.
- 14. The composition produced by the method of claim 6.
- 15. The composition produced by the method of claim 7.
- 16. The composition produced by the method of claim 8.
BACKGROUND OF THE INVENTION
The Government has rights in this invention pursuant to Contract No. F33615-83-C-5084 awarded by the Department of the Air Force.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4582754 |
Ryoke et al. |
Apr 1986 |
|
4731191 |
Swihart |
Mar 1988 |
|
4985166 |
Leising et al. |
Jan 1991 |
|
Foreign Referenced Citations (1)
Number |
Date |
Country |
319828 |
Jun 1989 |
EPX |