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US4745205A
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Novel preceramic polymers derived from cyclic silazanes and halogenated disilanes and a method for their preparation
Assignee: Dow Silicones Corp
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Filing: 1986-11-03
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Granted: 1988-05-17
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Expires: 2006-11-03
Abstract
Abstract Novel polymethyl(disilyl)silazanes are prepared from cyclic silazanes and certain halogenated disilanes. Thus, the reaction of a mixture of {(CH3)2 SiNH}x, where x is 3 and 4, and halogenated mixed disilanes give one of the inventive products.
Inventors
- 👤 Loren A. Haluska
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:15
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/60; C08G77/62; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565; C04B35/571; C04B35/58; C04B35/584; C04B35/589
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
148 words
A method of preparing a preceramic polymer comprising contacting and reacting in an inert, essentially anhydrous atmosphere, a chlorine-containing disilane or a mixture of chlorine-containing disilanes, of the general formula (Cl d R' e Si) 2 with a cyclic silazane, or a mixture of cyclic silazanes selected from the group consisting of cyclic silazanes having the general formula (i) (CH 3 R"SiNH) x and (ii) (C 6 H 5 R"SiNH) x at a temperature in the range of 22° C. to 280° C. while distilling by produced volatile products, wherein R' and R" are each independently selected from the group consisting of hydrogen, vinyl, phenyl and alkyl radicals containing 1 to 3 carbon atoms; d has a value of 0.5 to 3; e has a value of 0 to 2.4 and the sum of (d+e) is equal to three and x is an integer of 3 to 6.
Claim 2
Independent Claim
148 words
A method of preparing a preceramic polymer comprising contacting and reacting in an inert, essentially anhydrous atmosphere, a chlorine-containing disilane or a mixture of chlorine-containing disilanes, of the general formula (Cl d R' e Si) 2 with a cyclic silazane, or a mixture of cyclic silazanes selected from the group consisting of cyclic silazanes having the general formula (i) (CH 3 R"SiNH) x and (ii) (C 6 H 5 R"SiNH) x at a temperature in the range of 22° C. to 280° C. while distilling by produced volatile products, wherein R' and R" are each independently selected from the group consisting of hydrogen, vinyl, phenyl and alkyl radicals containing 1 to 3 carbon atoms; d has a value of 0.5 to 3; e has a value of 0 to 2.4 and the sum of (d+e) is equal to three and x is an integer of 3 to 6.
Claim 3
Dependent Claim
28 words
A method as claimed in claim 1 wherein the disilane is a mixture of chlorine-containing disilanes and the cyclic silazane is {(CH 3 ) 2 SiNH} x .
Claim 4
Dependent Claim
14 words
A method as claimed in claim 2 wherein x has a value of 4.
Claim 5
Dependent Claim
14 words
A method as claimed in claim 2 wherein x has a value of 3.
Claim 6
Dependent Claim
38 words
A method as claimed in claim 1 wherein the disilane is a mixture of chlorine-containing disilanes and the cyclic silazanes are a mixture of {(CH 3 ) 2 SiNH} 4 and {(CH 3 ) 2 SiNH} 3 .
Claim 7
Dependent Claim
22 words
A method as claimed in claim 1 wherein the product is further treated with ammonia in an otherwise inert, essentially anhydrous atmosphere.
Claim 8
Dependent Claim
11 words
A composition of matter prepared by the method of claim 1.
Claim 9
Dependent Claim
30 words
A composition of matter as claimed in claim 7 wherein the disilane is a mixture of chlorine-containing disilanes and the cyclic silazane is {(CH 3 ) 2 SiNH} x .
Claim 10
Dependent Claim
16 words
A composition of matter as claimed in claim 8 wherein x has a value of 4.
Claim 11
Dependent Claim
16 words
A composition of matter as claimed in claim 8 wherein x has a value of 3.
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) | 1991-05-17 | 1991-11-16 | 1992-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-17 | 1995-11-16 | 1996-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-17 | 1999-11-16 | 2000-05-17 | $7700.00 | Window Closed / Lapsed |