US4772494A
Expired / Lapsed
US
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Method of spinning fibers and coating from an organopolysilazane composition containing free radical generators and capable of being crosslinked by an energy input
Assignee: Rhone Poulenc Specialites Chimiques
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Filing: 1987-10-01
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Granted: 1988-09-20
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Expires: 2007-10-01
Abstract
Abstract Method of spinning fibers and coating from an organopolysilazane composition that can be crosslinked by an energy input. The organopolysilazane composition comprises an organopolysilazane and a free radical generator in an amount effective to crosslink the organopolysilazane. The energy input capable of generated the radical may be provided in the form of heat, ultraviolet radiation, an electron beam, and the like. The crosslinked organopolysilazane compositions exhibit good thermal behavior and, in particular, can be used, after pyrolysis, as precursors of ceramic products.
Inventors
- 👤 Hugues Porte
- 👤 Jean-Jacques Lebrun
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:40
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/589; C04B41/45; C04B41/50; C04B41/5025; C04B41/5035; C04B41/80; C04B41/81; C04B41/85; C04B41/87; C08; C08G; C08G77/00; C08G77/60; C08G77/62; C08L; C08L83/00; C08L83/16; G; G03; G03F; G03F7/00; G03F7/004; G03F7/075; G03F7/0757
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
49 words
A method of spinning fibers comprising the step of spinning a fiber of an organopolysilazane composition that is capable of being crosslinked by an energy input, the organopolysilazane composition comprising (a) an organopolysilazane, and (b) at least one free radical generator in an amount effective to crosslink the organopolysilazane.
Claim 2
Independent Claim
49 words
A method of spinning fibers comprising the step of spinning a fiber of an organopolysilazane composition that is capable of being crosslinked by an energy input, the organopolysilazane composition comprising (a) an organopolysilazane, and (b) at least one free radical generator in an amount effective to crosslink the organopolysilazane.
Claim 3
Dependent Claim
23 words
The method of claim 1, wherein the organopolysilazane is chosen so that the viscosity at 25° C. is greater than 5,000 mPa s.
Claim 4
Dependent Claim
19 words
The method of claim 1, wherein the organopolysilazane composition is in the molten state in the absence a solvent.
Claim 5
Dependent Claim
13 words
The method of claim 1, wherein the organopolysilazane composition is in a solvent.
Claim 6
Dependent Claim
70 words
A process for covering a substrate with a ceramic material, comprising the steps of: (a) covering a substrate with an organopolysilazane composition comprising an organopolysilazane and a free radical generator in an amount effective to crosslink the organopolysilazane; (b) crosslinking the organopolysilazane composition; and (c) pyrolyzing the crosslinked organopolysilazane composition in a thermal treatment at a temperature in the range of from about the crosslinking temperature to about 2,000° C.
Claim 7
Dependent Claim
70 words
A process for covering a substrate with a ceramic material, comprising the steps of: (a) covering a substrate with an organopolysilazane composition comprising an organopolysilazane and a free radical generator in an amount effective to crosslink the organopolysilazane; (b) crosslinking the organopolysilazane composition; and (c) pyrolyzing the crosslinked organopolysilazane composition in a thermal treatment at a temperature in the range of from about the crosslinking temperature to about 2,000° C.
Claim 8
Dependent Claim
20 words
The process according to claim 5, wherein the thermal treatment range is from the crosslinking temperature to about 1500° C.
Claim 9
Dependent Claim
18 words
The process according to claim 5, wherein in step (a), the substrate is coated with the organopolysilazane composition.
Claim 10
Dependent Claim
18 words
The process according to claim 5, wherein in step (a), the substrate is impregnated with the organopolysilazane composition.
Claim 11
Dependent Claim
31 words
The process according to claim 5, wherein the organopolysilazane contains at least one SiR 1 group per molecule with R 1 being a hydrocarbon radical containing an unsaturated alkene or alkyne.
Claim 12
Dependent Claim
23 words
The process according to claim 5, wherein the free radical generator is selected from the group consisting of azo compounds and organic peroxides.
Claim 13
Dependent Claim
22 words
The process according to claim 10, wherein the organic peroxide is selected from the group consisting of cumyl peroxide and 2,5-dimethyl-2,5-di(tert-butylperoxy) hexane.
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) | 1991-09-20 | 1992-03-21 | 1992-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-20 | 1996-03-21 | 1996-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-20 | 2000-03-21 | 2000-09-20 | $7700.00 | Window Closed / Lapsed |