US4657991A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Precursor composition of silicon carbide
Assignee: Shin-Etsu Chemical Co Ltd
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Filing: 1985-10-15
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Granted: 1987-04-14
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Expires: 2005-10-15
Abstract
Abstract The precursor composition of silicon carbide fibers provided by the invention has greatly improved spinnability and can be spun at a very high spinning velocity to give a green filament which has a much larger tensile strength than those of conventional precursor materials and is capable of giving silicon carbide fibers having increased tensile strength by the infusibilization and calcination of the green filament of the composition under tension. The composition comprises from 80 to 99.9 parts by weight of a polycarbosilane polymer and from 20 to 0.01 part by weight of a silmethylene polymer having a degree of polymerization larger than the specified lower limit.
Inventors
- 👤 Minoru Takamizawa
- 👤 Taishi Kobayashi
- 👤 Toshinobu Ishihara
- 👤 Yoshihumi Takeda
- 👤 Akira Hayashida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:25
CPC Classifications
C; C08; C08G; C08G79/00; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565; C04B35/571; C08L; C08L83/00; C08L83/16
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
182 words
A precursor composition of silicon carbide which comprises: (a) from 80 to 99.9% by weight of a polycarbosilane polymer having a three-dimensional molecular structure obtained by heating at a temperature of 300°-650° C. in an atmosphere of an inert gas, a polysilane compound composed of one or a combination of one or more units selected from the group consisting of ##STR2## in which R 2 is a hydrogen atom or a monovalent hydrocarbon group selected from the class consisting of methyl, ethyl, vinyl and phenyl groups, or, a copolymer of said polysilane compound, and an organometallic compound containing a metal atom selected from the group consisting of boron, aluminum, titanium and zirconium, to effect pyrolytic polycondensation reaction, and (b) from 0.1 to 20 parts by weight of a polymeric organosilicon compound having a linear molecular structure represented by the general formula R.sup.1 --SiR.sub.2 --CH.sub.2).sub.m H, in which R is a monovalent hydrocarbon group, R 1 is a monovalent group selected from the class consisting of hydroxy, amino, monovalent hydrocarbon and trialkylsiloxy groups and m is a positive integer not smaller than 100.
Claim 2
Dependent Claim
182 words
A precursor composition of silicon carbide which comprises: (a) from 80 to 99.9% by weight of a polycarbosilane polymer having a three-dimensional molecular structure obtained by heating at a temperature of 300°-650° C. in an atmosphere of an inert gas, a polysilane compound composed of one or a combination of one or more units selected from the group consisting of ##STR2## in which R 2 is a hydrogen atom or a monovalent hydrocarbon group selected from the class consisting of methyl, ethyl, vinyl and phenyl groups, or, a copolymer of said polysilane compound, and an organometallic compound containing a metal atom selected from the group consisting of boron, aluminum, titanium and zirconium, to effect pyrolytic polycondensation reaction, and (b) from 0.1 to 20 parts by weight of a polymeric organosilicon compound having a linear molecular structure represented by the general formula R.sup.1 --SiR.sub.2 --CH.sub.2).sub.m H, in which R is a monovalent hydrocarbon group, R 1 is a monovalent group selected from the class consisting of hydroxy, amino, monovalent hydrocarbon and trialkylsiloxy groups and m is a positive integer not smaller than 100.
Claim 3
Dependent Claim
46 words
The precursor composition of silicon carbide as claimed in claim 1 wherein the organometallic compound is an organoboron compound composed of the units represented by the general formula (--BR 3 --NR 4 --), in which R 3 and R 4 are each a monovalent hydrocarbon group.
Claim 4
Dependent Claim
18 words
The precursor composition of silicon carbide as claimed in claim 2 wherein the organoboron compound is 1,3,5-trimethyl-2,4,6-triphenyl borazine.
Claim 5
Dependent Claim
55 words
The precursor composition of silicon carbide as claimed in claim 1 wherein the organometallic compound is a compound represented by the general formula M(OR 3 ) 4 , in which M is an atom of a metal selected from the group consisting of aluminum, titanium and zirconium and R 3 is a monovalent hydrocarbon group.
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) | 1990-04-13 | 1990-10-13 | 1991-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-13 | 1994-10-13 | 1995-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-13 | 1998-10-13 | 1999-04-14 | $7700.00 | Window Closed / Lapsed |