US4987201A
Expired / Lapsed
US
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Boron-carbon-silicon polymers and the ceramic thereof
Assignee: National Aeronautics and Space Administration
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Filing: 1989-06-05
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Granted: 1991-01-22
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Expires: 2009-06-05
Abstract
Abstract The present invention relates to a process for the production of an organoborosilicon preceramic polymer of the structure: <IMAGE> <IMAGE> wherein R1 is selected from alkyl having from 1 to 10 carbon atoms or phenyl, and x is selected from 0, 1, 2 or 3; which is pyrolyzable to produce a refractory material comprising inorganic compounds of Si, C and B, which process comprises: contacting a silicon containing compound of the structure: (R1)x-Si (CH=CH2)4-x or (R1)x Si(C=CH)4-x with a boron containing compound selected from H3B:BH3, H3B:NH3, BH3:N(R2)3 wherein R2 is selected from methyl, ethyl, propyl, butyl or phenyl in an inert atmosphere at a temperature of between about 90 DEG and 170 DEG C. for between about 0.1 and 20 hr and recovering the prepolymer. The prepolymer is pyrolyzed to produce a ceramic article useful in high temperature (e.g., aerospace) or extreme environmental applications.
Inventors
- 👤 Salvatore R. Riccitiello
- 👤 Ming-Ta S. Hsu
- 👤 Timothy S. Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:50
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/60; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565; C04B35/571; C08G79/00; C08G79/08
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
134 words
A process for the production of an organoborosilicon ceramic prepolymer of the structure: ##STR8## wherein R 1 is selected from alkyl having from 1 to 10 carbon atoms or phenyl, and x is selected from 0, 1, 2 or 3; which prepolymer is pyrolyzable to produce a refractory material comprising ceramic compounds of Si, C and B, which process comprises: contacting a silicon containing compound of the structure: (R.sup.1).sub.x --Si (CH═CH.sub.2).sub.4-x with a boron containing compound selected from H 3 B:BH 3 , H 3 B:NH 3 , or BH 3 :N(R 2 ) 3 wherein R 2 is selected from methyl, ethyl, propyl, butyl, or phenyl in an inert anhydrous atmosphere at a temperature of between about 90° and 170° C. for between about 0.1 and 120 hr; and recovering the ceramic prepolymer.
Claim 2
Dependent Claim
134 words
A process for the production of an organoborosilicon ceramic prepolymer of the structure: ##STR8## wherein R 1 is selected from alkyl having from 1 to 10 carbon atoms or phenyl, and x is selected from 0, 1, 2 or 3; which prepolymer is pyrolyzable to produce a refractory material comprising ceramic compounds of Si, C and B, which process comprises: contacting a silicon containing compound of the structure: (R.sup.1).sub.x --Si (CH═CH.sub.2).sub.4-x with a boron containing compound selected from H 3 B:BH 3 , H 3 B:NH 3 , or BH 3 :N(R 2 ) 3 wherein R 2 is selected from methyl, ethyl, propyl, butyl, or phenyl in an inert anhydrous atmosphere at a temperature of between about 90° and 170° C. for between about 0.1 and 120 hr; and recovering the ceramic prepolymer.
Claim 3
Dependent Claim
25 words
The process of claim 1 wherein in the silicon containing compound, x is 0 and the boron containing compound is BH 3 :BH 3 .
Claim 4
Dependent Claim
51 words
The process of claim 1 wherein the silicon containing compound, x is 0, and the boron containing compound is H 3 B:NH 3 , with the proviso that when H 3 B:NH 3 is used, nitrogen remains in the organoborosilicon ceramic prepolymer in between about 1.5 and 13 percent by weight.
Claim 5
Dependent Claim
31 words
The process of claim 1 wherein in the silicon containing compound, R 1 is methyl, x is 2, and the boron containing compound is H 3 B:N(R 2 ) 3 .
Claim 6
Dependent Claim
19 words
The process of claim 1 wherein the molecular weight of the prepolymer, is between about 500 and 100,000 daltons.
Claim 7
Dependent Claim
11 words
The organic/inorganic ceramic prepolymer produced by the process of claim 1.
Claim 8
Dependent Claim
11 words
The organic ceramic prepolymer produced by the process of claim 2.
Claim 9
Dependent Claim
11 words
The organic/inorganic ceramic prepolymer produced by the process of claim 3.
Claim 10
Dependent Claim
133 words
A process for the production of an organoborosilicon ceramic prepolymer of the structure: ##STR9## wherein R 1 is selected from alyl having from 1 to 10 carbon atoms or phenyl, and x is selected from 0, 1, 2 or 3; which prepolymer is pyrolyzable to produce a refractory material comprising ceramic compounds of Si, C and B, which process comprises: contacting a silicon containing compound of the structure: (R.sup.1).sub.x --Si--(C.tbd.CH).sub.4-x with a boron containing compound selected from H 3 B:BH 3 , H 3 B:NH 3 , or BH 3 :N(R 2 ) 3 wherein R 2 is selected from methyl, ethyl, propyl, butyl, or phenyl in an inert anhydrous atmosphere at a temperature of between about 90° and 170° C. for between about 0.1 and 120 hr; and recovering the ceramic prepolymer.
Claim 11
Dependent Claim
133 words
A process for the production of an organoborosilicon ceramic prepolymer of the structure: ##STR9## wherein R 1 is selected from alyl having from 1 to 10 carbon atoms or phenyl, and x is selected from 0, 1, 2 or 3; which prepolymer is pyrolyzable to produce a refractory material comprising ceramic compounds of Si, C and B, which process comprises: contacting a silicon containing compound of the structure: (R.sup.1).sub.x --Si--(C.tbd.CH).sub.4-x with a boron containing compound selected from H 3 B:BH 3 , H 3 B:NH 3 , or BH 3 :N(R 2 ) 3 wherein R 2 is selected from methyl, ethyl, propyl, butyl, or phenyl in an inert anhydrous atmosphere at a temperature of between about 90° and 170° C. for between about 0.1 and 120 hr; and recovering the ceramic prepolymer.
Claim 12
Dependent Claim
25 words
The process of claim 9 wherein in the silicon containing compound, x is 0 and the boron containing compound is BH 3 :BH 3 .
Claim 13
Dependent Claim
51 words
The process of claim 9 wherein the silicon containing compound, x is 0, and the boron containing compound is H 3 B:NH 3 , with the proviso that when H 3 B:NH 3 is used, nitrogen remains in the organoborosilicon ceramic prepolymer in between about 1.5 and 13 percent by weight.
Claim 14
Dependent Claim
31 words
The process of claim 9 wherein in the silicon containing compound, R 1 is methyl, x is 2, and the boron containing compound is H 3 B:N(R 2 ) 3 .
Claim 15
Dependent Claim
19 words
The process of claim 9 wherein the molecular weight of the prepolymer is between about 500 and 100,000 daltons.
Claim 16
Dependent Claim
11 words
The organic/inorganic ceramic prepolymer produced by the process of claim 9.
Claim 17
Dependent Claim
11 words
The organic/inorganic ceramic prepolymer produced by the process of claim 10.
Claim 18
Dependent Claim
11 words
The organic/inorganic ceramic prepolymer produced by the process of claim 11.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-01-21 | 1994-07-23 | 1995-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-21 | 1998-07-23 | 1999-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-21 | 2002-07-23 | 2003-01-22 | $7700.00 | Window Closed / Lapsed |