US4950381A
Expired / Lapsed
US
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Polysilazane and method for synthesis thereof
Assignee: JNC Corp
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Filing: 1988-06-10
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Granted: 1990-08-21
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Expires: 2008-06-10
Abstract
Abstract There is provided a new polysilazane product from a specific precursor. Desired molecular weight of the polysilazane can be obtained by selecting the proper molar ratio of R 1 SiHX 2 and R 2 R 3 SiX 2 as raw materials. The polysilazane is stable during storage without gelation. The polymerization of the precursor can be carried out without gelation even at a high temperature and hence can be completed in a short time. The polysilazane can be made into ceramic fibers by spinning from a solution and subsequent firing.
Inventors
- 👤 Hiroyuki Takeuchi
- 👤 Kaneo Noake
- 👤 Tamio Serita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:22
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/589; C04B35/56; C04B35/565; C04B35/571; C08; C08G; C08G77/00; C08G77/60; C08G77/62
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
128 words
An organic polymer comprising a polysilazane derived from a mixture of organohalosilanes comprising solely those represented by the formulas R 1 SiHX 2 and R 2 R 3 SiX 2 and having cyclic units with the skeletal backbone units: ##STR16## formed from the units: ##STR17## the cyclic units joined to one another by units: ##STR18## wherein R 1 , R 2 , R 3 each represents a lower alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted vinyl group, a substituted or unsubstituted allyl group, a substituted or unsubstituted lower aryl group having 6 to 10 carbon atoms, or tri (lower)alkyl- or di(lower)alkylsilyl group, or di(lower)alkyl-amino group, with R 1 , R 2 , and R 3 being the same or different from one another.
Claim 2
Dependent Claim
128 words
An organic polymer comprising a polysilazane derived from a mixture of organohalosilanes comprising solely those represented by the formulas R 1 SiHX 2 and R 2 R 3 SiX 2 and having cyclic units with the skeletal backbone units: ##STR16## formed from the units: ##STR17## the cyclic units joined to one another by units: ##STR18## wherein R 1 , R 2 , R 3 each represents a lower alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted vinyl group, a substituted or unsubstituted allyl group, a substituted or unsubstituted lower aryl group having 6 to 10 carbon atoms, or tri (lower)alkyl- or di(lower)alkylsilyl group, or di(lower)alkyl-amino group, with R 1 , R 2 , and R 3 being the same or different from one another.
Claim 3
Dependent Claim
20 words
A polysilazane as claimed in claim 1, wherein the content of the unit (B) in said precursor is 1≈60 mol%.
Claim 4
Dependent Claim
25 words
A polysilazane as claimed in claim 1, wherein R 1 , R 2 , and R 3 in said each formula are all methyl group.
Claim 5
Dependent Claim
157 words
A process for producing a polysilazane which comprises: (a) a reacting anhydrous ammonia with a mixture of organohalosilanes comprising solely those represented by the formulas R 1 SiHX 2 and R 2 R 3 SiX 2 in a solution, thereby forming a cyclic or linear silazane precursor, and (b) deprotonating, cyclizing, and crosslinking said precursor in the presence of a basic catalyst capable of deprotonating hydrogen from a nitrogen atom adjacent to a silicon atom, thereby forming a polymer wherein R 1 , R 2 and R 3 each represents a lower alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted vinyl group, a substituted or unsubstituted allyl group, a substituted or unsubstituted lower aryl group having 6 to 10 carbon atoms, or tri(lower)alkyl- or di(lower)alkylsilyl group, or di(lower)alkyl-amino group, with R 1 , R 2 , and R 3 being the same or different from one another and X represents a halogen atom.
Claim 6
Dependent Claim
157 words
A process for producing a polysilazane which comprises: (a) a reacting anhydrous ammonia with a mixture of organohalosilanes comprising solely those represented by the formulas R 1 SiHX 2 and R 2 R 3 SiX 2 in a solution, thereby forming a cyclic or linear silazane precursor, and (b) deprotonating, cyclizing, and crosslinking said precursor in the presence of a basic catalyst capable of deprotonating hydrogen from a nitrogen atom adjacent to a silicon atom, thereby forming a polymer wherein R 1 , R 2 and R 3 each represents a lower alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted vinyl group, a substituted or unsubstituted allyl group, a substituted or unsubstituted lower aryl group having 6 to 10 carbon atoms, or tri(lower)alkyl- or di(lower)alkylsilyl group, or di(lower)alkyl-amino group, with R 1 , R 2 , and R 3 being the same or different from one another and X represents a halogen atom.
Claim 7
Dependent Claim
31 words
A process for producing a polysilazane as claimed in claim 4, wherein the molar ratio of R 1 SiHX 2 to R 2 R 3 SiX 2 is 2:3 to 100:1.
Claim 8
Dependent Claim
29 words
A process for producing a polysilazane as claimed in claim 4, wherein R 1 , R 2 , and R 3 in said each formula are all methyl group.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-08-20 | 1994-02-19 | 1994-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-20 | 1998-02-19 | 1998-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-20 | 2002-02-19 | 2002-08-21 | $7700.00 | Window Closed / Lapsed |