US4910173A
Expired / Lapsed
US
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Preceramic compositions and ceramic products
Assignee: Ethyl Corp
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Filing: 1989-04-14
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Granted: 1990-03-20
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Expires: 2009-04-14
Abstract
Abstract Preceramic compositions which have particular utility in providing protective ceramic coatings having low moisture sensitivity on carbon/carbon composites, graphite, carbon fibers, and other normally oxidizable materials are prepared by dispersing about 0.1-1.0 part by weight of a Group IIA metal salt with an organoborosilazane polymer solution obtained by reacting about 0.25-20 parts by weight of a trialkoxy-, triaryloxy-, or tri(arylalkoxy)boroxine with one part by weight of a polysilazane in an organic solvent and, if desired, heating the dispersion to convert it to a solution.
Inventors
- 👤 Leonard M. Niebylski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:39
CPC Classifications
C; C08; C08L; C08L83/00; C08L83/16; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/589; C04B41/00; C04B41/45; C04B41/4505; C04B41/455; C04B41/4554; C04B41/80; C04B41/81; C08G; C08G79/00; C23; C23C; C23C18/00; C23C18/02; C23C18/12; C23C18/1204; C23C18/1208; C23C18/122
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
47 words
A process which comprises dispersing about 0.1-1.0 part by weight of a Group IIA metal salt in an organoborosilazane polymer solution obtained by reacting about 0.25-20 parts by weight of a trialkoxy-, triaryloxy-, or tri(arylalkoxy)boroxine with one part by weight of a polysilazane in an organic solvent.
Claim 2
Dependent Claim
47 words
A process which comprises dispersing about 0.1-1.0 part by weight of a Group IIA metal salt in an organoborosilazane polymer solution obtained by reacting about 0.25-20 parts by weight of a trialkoxy-, triaryloxy-, or tri(arylalkoxy)boroxine with one part by weight of a polysilazane in an organic solvent.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein the salt is a fluoride, tetrafluoroborate, oxide, oxyfluoride, or oxynitride.
Claim 4
Dependent Claim
11 words
The process of claim 2 wherein the salt is calcium tetrafluoroborate.
Claim 5
Dependent Claim
11 words
The process of claim 2 wherein the salt is barium fluoride.
Claim 6
Dependent Claim
9 words
The process of claim wherein the boroxine is trimethoxyboroxine.
Claim 7
Dependent Claim
51 words
The process of claim 1 wherein the polysilazane is a polymer prepared by reacting an organodihalosilane with ammonia, treating the ammonolysis product with a basic catalyst which is capable of deprotonating an NH group that is adjacent to an SiH group, and quenching the resultant product with an electrophilic quenching reagent.
Claim 8
Dependent Claim
17 words
The process of claim 6 wherein the organodihalosilane is methyldichlorosilane and the basic catalyst is potassium hydride.
Claim 9
Dependent Claim
34 words
The process of claim 1 wherein the composition obtained by dispersing the salt in the polymer solution is heated at about 120°-150° C. until at least a portion of the salt has been solubilized.
Claim 10
Dependent Claim
62 words
The process of claim 8 wherein about 0.1-1.0 part by weight of calcium tetrafluoroborate is dispersed in an organoborosilazane polymer solution obtained by reacting about 3-4 parts by weight of trimethoxyboroxine with one part by weight of a polysilazane prepared by reacting methyldichlorosilane with ammonia, treating the ammonolysis product with potassium hydride, and quenching the resultant product with an electrophilic quenching reagent.
Claim 11
Dependent Claim
62 words
The process of claim 8 wherein about 0.1-1.0 part by weight of barium fluoride is dispersed in an organoborosilazane polymer solution obtained by reacting about 3-4 parts by weight of trimethoxyboroxine with one part by weight of a polysilazane prepared by reacting methyldichlorosilane with ammonia, treating the ammonolysis product with potassium hydride, and quenching the resultant product with an electrophilic quenching reagent.
Claim 12
Dependent Claim
9 words
A dispersion prepared by the process of claim 1.
Claim 13
Dependent Claim
9 words
A solution prepared by the process of claim 8.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-03-19 | 1993-09-18 | 1994-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-19 | 1997-09-18 | 1998-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-19 | 2001-09-18 | 2002-03-20 | $7700.00 | Window Closed / Lapsed |