US5169908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Curable boron modified hydropolysilazane polymers
Assignee: Dow Silicones Corp
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Filing: 1991-12-20
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Granted: 1992-12-08
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Expires: 2011-12-20
Abstract
Abstract The present invention relates to a method of preparing boron modified hydropolysilazane polymers. The method comprises reacting a hydropolysilazane polymer with borane for a time sufficient to form the boron modified hydropolysilazane polymer. The invention also relates to the novel polymers produced by the above process.
Inventors
- 👤 Gregg A. Zank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:27
CPC Classifications
C; C08; C08G; C08G79/00; C08G79/08; C08G77/00; C08G77/48; C08G77/56
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
106 words
A method of forming a boron modified hydropolysilazane polymer comprising: reacting a R 3 SiNH-containing hydropolysilazane polymer with borane for a time sufficient to form the boron modified hydropolysilazane polymer, wherein the R 3 SiNH-containing hydropolysilazane polymer is formed by a process consisting of contacting and reacting, in an inert, essentially anhydrous atmosphere, trichlorosilane with a disilazane at a temperature in the range of 25° to 300° C. while distilling by-produced volatile products, wherein said disilazane has the general formula (R 3 Si) 2 NH where R is selected from the group consisting of vinyl, hydrogen, phenyl, and alkyl radicals containing 1 to 3 carbon atoms.
Claim 2
Independent Claim
106 words
A method of forming a boron modified hydropolysilazane polymer comprising: reacting a R 3 SiNH-containing hydropolysilazane polymer with borane for a time sufficient to form the boron modified hydropolysilazane polymer, wherein the R 3 SiNH-containing hydropolysilazane polymer is formed by a process consisting of contacting and reacting, in an inert, essentially anhydrous atmosphere, trichlorosilane with a disilazane at a temperature in the range of 25° to 300° C. while distilling by-produced volatile products, wherein said disilazane has the general formula (R 3 Si) 2 NH where R is selected from the group consisting of vinyl, hydrogen, phenyl, and alkyl radicals containing 1 to 3 carbon atoms.
Claim 3
Dependent Claim
10 words
The method of claim 1 wherein the disilazane is hexamethyldisilazane.
Claim 4
Dependent Claim
17 words
The method of claim 1 wherein the borane is in the form of a borane-lewis base complex.
Claim 5
Dependent Claim
15 words
The method of claim 3 wherein the borane is in the form of borane-tetrahydrofuran complex.
Claim 6
Dependent Claim
32 words
The method of claim 1 wherein the amount of borane used in this reaction is in the range of from about 0.01 to about 1 equivalent borane per 100 g hydropolysilazane polymer.
Claim 7
Dependent Claim
32 words
The method of claim 5 wherein the amount of borane used in this reaction is in the range of from about 0.05 to about 0.5 equivalent borane per 100 g hydropolysilazane polymer.
Claim 8
Dependent Claim
31 words
The method of claim 1 wherein the reaction of the hydropolysilazane polymer with the borane is conducted in a solvent selected from the group consisting of alkanes, ethers, and aromatic hydrocarbons.
Claim 9
Dependent Claim
12 words
The boron modified hydropolysilazane polymer produced by the process of claim 1.
Claim 10
Dependent Claim
12 words
The boron modified hydropolysilazane polymer produced by the process of claim 2.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-12-08 | 1996-06-08 | 1996-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-08 | 2000-06-08 | 2000-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-08 | 2004-06-08 | 2004-12-08 | $7700.00 | Window Closed / Lapsed |