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US4800221A
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Silicon carbide preceramic polymers
Assignee: Dow Silicones Corp
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Filing: 1987-08-25
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Granted: 1989-01-24
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Expires: 2007-08-25
Abstract
Abstract Preceramic polymers composed of [R 2 SiC.tbd.CSiR 2 ] and, optionally, [R 2 Si] units are described where R is hydrogen, an alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, or vinyl radicals. These preceramic polymers may be converted into silicon carbide-containing ceramic materials by pyrolysis at elevated temperatures.
Inventors
- 👤 Ollie W. Marko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:38
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/60; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565; C04B35/571
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
58 words
A preceramic polymer composed of ##STR8## units where there are present 0 to 25 mole percent [R 2 Si] units and 75 to 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units and where each R is independently selected from the group consisting of hydrogen, alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, and vinyl radicals.
Claim 2
Dependent Claim
58 words
A preceramic polymer composed of ##STR8## units where there are present 0 to 25 mole percent [R 2 Si] units and 75 to 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units and where each R is independently selected from the group consisting of hydrogen, alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, and vinyl radicals.
Claim 3
Dependent Claim
33 words
A perceramic polymer as defined in claim 1 where there are present 0 to 10 mole percent [R 2 Si] units and 90 to 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units.
Claim 4
Dependent Claim
21 words
A perceramic polymer as defined in claim 2 where there are present 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units.
Claim 5
Dependent Claim
12 words
A perceramic polymer as defined in claim 1 where R is methyl.
Claim 6
Dependent Claim
12 words
A perceramic polymer as defined in claim 2 where R is methyl.
Claim 7
Dependent Claim
12 words
A perceramic polymer as defined in claim 3 where R is methyl.
Claim 8
Dependent Claim
21 words
A preceramic polymer as defined in claim 1 where the preceramic polymer has a softening temperature of 50° to 300° C.
Claim 9
Dependent Claim
21 words
A preceramic polymer as defined in claim 2 where the perceramic polymer has a softening temperature of 50° to 300° C.
Claim 10
Dependent Claim
21 words
A preceramic polymer as defined in claim 3 where the preceramic polymer has a softening temperature of 50° to 300° C.
Claim 11
Independent Claim
149 words
A method of preparing a preceramic polymer composed of ##STR9## units where there are present 0 to 25 mole percent [R 2 Si] units and 75 to 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units and where each R is independently selected from the group consisting of hydrogen, alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, and vinyl radicals, said method consisting of reacting under anhydrous conditions in solution a mixture containing 0 to 25 mole percent of a silane of formula R 2 SiX 2 and 75 to 100 mole percent of acetylenic compound of formula R 2 XSiC.tbd.CSiXR 2 where each R is independently selected from the group consisting of hydrogen, alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, and vinyl radicals and X is halogen in the presence of a metal selected from the group consisting of lithium, sodium, and potassium.
Claim 12
Independent Claim
149 words
A method of preparing a preceramic polymer composed of ##STR9## units where there are present 0 to 25 mole percent [R 2 Si] units and 75 to 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units and where each R is independently selected from the group consisting of hydrogen, alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, and vinyl radicals, said method consisting of reacting under anhydrous conditions in solution a mixture containing 0 to 25 mole percent of a silane of formula R 2 SiX 2 and 75 to 100 mole percent of acetylenic compound of formula R 2 XSiC.tbd.CSiXR 2 where each R is independently selected from the group consisting of hydrogen, alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, and vinyl radicals and X is halogen in the presence of a metal selected from the group consisting of lithium, sodium, and potassium.
Claim 13
Dependent Claim
18 words
A method as defined in claim 10 where the metal is sodium and X is chlorine or bromine.
Claim 14
Dependent Claim
46 words
A method as defined in claim 10 where the mixture contains 0 to 10 mole percent of a silane of formula R 2 SiX 2 and 90 to 100 mole percent of acetylenic compound of formula R 2 XSiC.tbd.CSiXR 2 and X is chlorine or bromine.
Claim 15
Dependent Claim
41 words
A method as defined in claim 11 where the mixture contains 0 to 10 mole percent of a silane of formula R 2 SiX 2 and 90 to 100 mole percent of acetylenic compound of formula R 2 XSiC.tbd.CSiXR 2 .
Claim 16
Dependent Claim
24 words
A method as defined in claim 12 where the mixture contains 100 mole percent of acetylenic compound of formula R 2 XSiC.tbd.CSiXR 2 .
Claim 17
Dependent Claim
24 words
A method as defined in claim 13 where the mixture contains 100 mole percent of acetylenic compound of formula R 2 XSiC.tbd.CSiXR 2 .
Claim 18
Dependent Claim
11 words
A method as defined in claim 10 where R is methyl.
Claim 19
Dependent Claim
11 words
A method as defined in claim 13 where R is methyl.
Claim 20
Dependent Claim
11 words
A method as defined in claim 15 where R is methyl.
Claim 21
Dependent Claim
20 words
A method as defined in claim 10 where the preceramic polymer has a softening temperature of 50° to 300° C.
Claim 22
Independent Claim
102 words
A method of preparing a silicon carbide-containing ceramic material, which method consists of heating a preceramic polymer to at least 750° C. in an inert atmosphere or in a vacuum until the preceramic polymer is converted into a silicon carbide-containing ceramic material where the preceramic polymer is composed of ##STR10## units where there are present 0 to 25 mole percent [R 2 Si] units and 75 to 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units and where each R is independently selected from the group consisting of hydrogen, alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, and vinyl radicals.
Claim 23
Independent Claim
102 words
A method of preparing a silicon carbide-containing ceramic material, which method consists of heating a preceramic polymer to at least 750° C. in an inert atmosphere or in a vacuum until the preceramic polymer is converted into a silicon carbide-containing ceramic material where the preceramic polymer is composed of ##STR10## units where there are present 0 to 25 mole percent [R 2 Si] units and 75 to 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units and where each R is independently selected from the group consisting of hydrogen, alkyl radicals containing 1 to 8 carbon atoms, phenyl radicals, and vinyl radicals.
Claim 24
Dependent Claim
36 words
A method as defined in claim 20 where in the preceramic polymer there are present 0 to 10 mole percent [R 2 Si] units and 90 to 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units.
Claim 25
Dependent Claim
24 words
A method as defined in claim 20 where in the preceramic polymer there are present 100 mole percent [R 2 SiC.tbd.CSiR 2 ] units.
Claim 26
Dependent Claim
11 words
A method as defined in claim 20 where R is methyl.
Claim 27
Dependent Claim
11 words
A method as defined in claim 21 where R is methyl.
Claim 28
Dependent Claim
11 words
A method as defined in claim 22 where R is methyl.
Claim 29
Dependent Claim
20 words
A method as defined in claim 20 where the preceramic polymer has a softening temperature of 50° to 300° C.
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) | 1992-01-24 | 1992-07-25 | 1993-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-24 | 1996-07-25 | 1997-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-24 | 2000-07-25 | 2001-01-24 | $7700.00 | Window Closed / Lapsed |