US4581468A
Expired / Lapsed
US
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Boron nitride preceramic polymers
Assignee: ULTRASYSTEMS Inc A CORP OF
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Filing: 1985-05-13
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Granted: 1986-04-08
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Expires: 2005-05-13
Abstract
Abstract B-triamino-N-tris(trialkylsilyl)borazines, their condensation products, and the transformation of these into preceramic polymers amenable to fiber drawing and ultimately boron nitride fiber formation.
Inventors
- 👤 Kazimiera J. L. Paciorek
- 👤 Reinhold H. Kratzer
- 👤 David H. Harris
- 👤 Mark E. Smythe
- 👤 Patrick F. Kimble
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:03
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/62227; C04B35/515; C04B35/58; C04B35/583; C07; C07F; C07F7/00; C07F7/02; C07F7/08; C07F7/10; C08; C08G; C08G79/00; C08G79/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
18 words
B-triamino-N-tris(trialkylsilyl)borazines ##STR3## wherein R is methyl, ethyl, or butyl of the general formula C n H 2n+1 .
Claim 2
Dependent Claim
18 words
B-triamino-N-tris(trialkylsilyl)borazines ##STR3## wherein R is methyl, ethyl, or butyl of the general formula C n H 2n+1 .
Claim 3
Dependent Claim
2 words
B-triamino-N-tris(trimethylsilyl)borazine ##STR4##
Claim 4
Dependent Claim
2 words
B-triamino-N-tris(trimethylsilyl)borazine ##STR4##
Claim 5
Dependent Claim
32 words
Condensed B-triamino-N-tris(trialkylsilyl)borazines, singly and doubly bridged and mixtures thereof ##STR5## where R is methyl, ethyl, or butyl of the general formula C n H 2n+1 and where x is a positive integer.
Claim 6
Dependent Claim
32 words
Condensed B-triamino-N-tris(trialkylsilyl)borazines, singly and doubly bridged and mixtures thereof ##STR5## where R is methyl, ethyl, or butyl of the general formula C n H 2n+1 and where x is a positive integer.
Claim 7
Dependent Claim
19 words
Condensed B-triamino-N-tris(trimethylsilyl)borazines, singly and doubly bridged and mixtures thereof ##STR6## where x=1, 2, 3, 4, 5, 6, 7, 8.
Claim 8
Dependent Claim
19 words
Condensed B-triamino-N-tris(trimethylsilyl)borazines, singly and doubly bridged and mixtures thereof ##STR6## where x=1, 2, 3, 4, 5, 6, 7, 8.
Claim 9
Independent Claim
73 words
A method for condensing B-triamino-N-tris(trialkylsilyl)borazines and their dimers, trimers, tetramers, and octamers having the formula ##STR7## where R is methyl, ethyl, or butyl of the general formula C n H 2n+1 and where x is a positive integer from 1 to 8, into preceramic polymers by gradual heat treatment from about 50° C. to 300° C. over a period of time varying from about 8 hr to 250 hr in an inert atmosphere.
Claim 10
Independent Claim
73 words
A method for condensing B-triamino-N-tris(trialkylsilyl)borazines and their dimers, trimers, tetramers, and octamers having the formula ##STR7## where R is methyl, ethyl, or butyl of the general formula C n H 2n+1 and where x is a positive integer from 1 to 8, into preceramic polymers by gradual heat treatment from about 50° C. to 300° C. over a period of time varying from about 8 hr to 250 hr in an inert atmosphere.
Claim 11
Dependent Claim
18 words
The method of claim 8 wherein the compounds are condensed B-triamino-N-tris(trimethylsilyl)borazines, singly and doubly bridged and mixtures thereof.
Claim 12
Dependent Claim
37 words
The process of claim 6 further comprising heating the preceramic polymers in an ammonia atmosphere from about 60° C. to 1000° C. over time periods from about 8 hours to 27 days to form carbon-free boron nitride.
Claim 13
Dependent Claim
37 words
The process of claim 5 further comprising heating the preceramic polymers in an ammonia atmosphere from about 60° C. to 1000° C. over time periods from about 8 hours to 27 days to form carbon-free boron nitride.
References Cited (Backward Citations)
US3382279A
Cited
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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) | 1989-04-07 | 1989-10-07 | 1990-04-08 | $2000.00 | Window Closed / Lapsed |
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