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US4656300A
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Process for a thermal treatment of a polysilazane containing .tbd.SiH groups and .tbd.Si--NH-- groups
Assignee: Rhone Poulenc Specialites Chimiques
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Filing: 1986-06-25
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Granted: 1987-04-07
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Expires: 2006-06-25
Abstract
Abstract A process for the thermal treatment of a polysilazane at a temperature from about 40° C. to 220° C. The polysilazane contains on average at least two, preferably at least three, .tbd.SiH groups per molecule and at least two ##STR1## groups and, if appropriate, unsaturated aliphatic hydrocarbon groups bonded to the silicon atoms. The polysilazanes treated in this manner have good thermal behavior and can be used in particular as precursors of ceramic products with a high yield of inorganic products.
Inventors
- 👤 Jean-Jacques Lebrun
- 👤 Hugues Porte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:16
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; C08L; C08L83/00; C08L83/16
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
47 words
A process for the treatment of a polysilazane comprising the step of thermally treating at least one polysilazane at a temperature of from about 40° C. to 220° C., the polysilazane comprising on average at least two .tbd.SiH groups and at least two ##STR15## groups per molecule.
Claim 2
Dependent Claim
47 words
A process for the treatment of a polysilazane comprising the step of thermally treating at least one polysilazane at a temperature of from about 40° C. to 220° C., the polysilazane comprising on average at least two .tbd.SiH groups and at least two ##STR15## groups per molecule.
Claim 3
Dependent Claim
16 words
The process of claim 1, wherein the polysilazane has at least three .tbd.SiH groups per molecule.
Claim 4
Dependent Claim
34 words
The process of claim 1, wherein said at least one polysilazane is thermally treated along with a second polysilazane free of .tbd.SiH groups but containing unsaturated aliphatic hydrocarbon groups bonded to the silicon atom.
Claim 5
Dependent Claim
24 words
The process of claim 3, wherein the molar ratio of SiH groups to the unsaturated aliphatic hydrocarbon groups is from about 0.5 to 5.
Claim 6
Dependent Claim
14 words
The process of claim 4, wherein the molar ratio is from 0.8 to 2.
Claim 7
Dependent Claim
21 words
The process of claim 1, wherein the thermal treatment is conducted at a temperature from about 100° C. to 220° C.
Claim 8
Dependent Claim
16 words
The process of claim 6, wherein the polysilazane has at least three .tbd.SiH groups per molecule.
Claim 9
Dependent Claim
21 words
The process of claim 1, wherein the thermal treatment is conducted for a time from about 1 minute to 24 hours.
Claim 10
Dependent Claim
19 words
The process of claim 1, wherein the thermal treatment is carried out at a pressure greater than atmospheric pressure.
Claim 11
Dependent Claim
15 words
The process of claim 1, wherein the thermal treatment is carried out at atmospheric pressure.
Claim 12
Dependent Claim
19 words
The process of claim 1, wherein the thermal treatment is carried out at a pressure less than atmospheric pressure.
Claim 13
Dependent Claim
16 words
The process of claim 1, wherein the thermal treatment is carried out in an inert atmosphere.
Claim 14
Dependent Claim
21 words
The process of claim 1, wherein the polysilazane has a viscosity from about 10 mPas to 5000 mPas at 25° C.
Claim 15
Dependent Claim
15 words
The process of claim 12, wherein the viscosity is from 100 mPas to 1000 mPas.
Claim 16
Dependent Claim
17 words
The process of claim 1, wherein the thermal treatment is carried out in an organic solvent solution.
Claim 17
Dependent Claim
18 words
The process of claim 1, wherein the thermal treatment is carried out in the absence of a solvent.
Claim 18
Dependent Claim
19 words
The process of claim 1, wherein said polysilazane also contains unsaturated aliphatic hydrocarbon groups bonded to the silicon atoms.
Claim 19
Dependent Claim
24 words
The process of claim 17, wherein the molar ratio of SiH groups to the unsaturated aliphatic hydrocarbon groups is from about 0.5 to 5.
Claim 20
Dependent Claim
9 words
A polysilazane produced by the process of claim 1.
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) | 1990-04-06 | 1990-10-06 | 1991-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-06 | 1994-10-06 | 1995-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-06 | 1998-10-06 | 1999-04-07 | $7700.00 | Window Closed / Lapsed |