US4866149A
Expired / Lapsed
US
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Process for catalytic treatment of a polysilazane containing on average at least two hydrocarbon groups having aliphatic unsaturation per molecule
Assignee: Rhone Poulenc Specialites Chimiques
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Filing: 1986-11-28
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Granted: 1989-09-12
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Expires: 2006-11-28
Abstract
Abstract A process for treating a polysilazane, characterized in that a polysilazane possessing on average at least two, and preferably at least three, hydrocarbon groups having aliphatic unsaturation per molecule is treated catalytically in the presence of a catalytically efficient amount of a co-ordination catalyst. The polysilazanes treated in this manner possess high thermal resistance and can be used, in particular, as precursors of ceramic products, with a high yield of inorganic product.
Inventors
- 👤 Jean-Jacque Lebrun
- 👤 Hugues Porte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:40
CPC Classifications
C; C08; C08F; C08F4/00; C08F4/06; C08L; C08L83/00; C08L83/16; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/589; C08G; C08G77/00; C08G77/60; C08G77/62
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
50 words
A process for catalytic treatment of a polysilazane comprising catalytically contacting at least one starting polysilazane having on average at least two hydrocarbon groups having aliphatic unsaturation in each molecule, with a catalytically effective amount of a catalyst for coordination of aliphatic unsaturation, wherein said catalyst is a Bronsted acid.
Claim 2
Dependent Claim
50 words
A process for catalytic treatment of a polysilazane comprising catalytically contacting at least one starting polysilazane having on average at least two hydrocarbon groups having aliphatic unsaturation in each molecule, with a catalytically effective amount of a catalyst for coordination of aliphatic unsaturation, wherein said catalyst is a Bronsted acid.
Claim 3
Dependent Claim
23 words
A process according to claim 1 wherein said polysilazane has on average at least three hydrocarbon groups having aliphatic unsaturation in each molecule.
Claim 4
Dependent Claim
21 words
A process according to claim 1 wherein said catalyst is selected from the group consisting of strong organic or inorganic acids.
Claim 5
Dependent Claim
29 words
A process according to claim 3 wherein said catalyst is present at a concentration between about 10 ppm and 5,000 ppm of acid with respect to said starting polysilazane.
Claim 6
Dependent Claim
21 words
A process according to claim 3 wherein said catalyst is selected from the group consisting of strong organic or inorganic acids.
Claim 7
Dependent Claim
31 words
A process according to claim 5 wherein said catalyst is selected from the group consisting of trifluoromethanesulphonic, perchloric, trichloromethanesulphonic, trichloromethanecarboxylic, trichloroacetic, hydrochloric, acetic, nitric, picric, pyrophosphoric, chromic, p-toluenesulphonic and chloroplatinic acids.
Claim 8
Dependent Claim
29 words
A process according to claim 5 wherein said catalyst is selected from the group consisting of ion exchange resins posessing strong acid anions absorbed or bound to the resin.
Claim 9
Dependent Claim
35 words
A process according to claim 5 wherein said catalyst is selected from the group consisting of acid earths and porous inorganic supports covered with a polymeric film bearing a sulphonic acid or phosphoric acid group.
Claim 10
Dependent Claim
17 words
A process according to claim 1 wherein said treatment of a polysilazane is conducted without a solvent.
Claim 11
Dependent Claim
21 words
A process according to claim 1 wherein said treatment of a polysilazane is conducted in the presence of an organic solvent.
Claim 12
Dependent Claim
21 words
A process according to claim 2 wherein said treatment of a polysilazane is conducted in the presence of an organic solvent.
Claim 13
Dependent Claim
24 words
A process according to claim 10 wherein said solvent is selected from the group consisting of toluene, methylene chloride, benzene, xylene, hexane and heptane.
Claim 14
Dependent Claim
20 words
A process according to claim 3 wherein said treatment is conducted at a temperature between 20° C. and 180° C.
Claim 15
Dependent Claim
18 words
A process as recited in claim 13 wherein said treatment is conducted between 120° C. and 160° C.
Claim 16
Dependent Claim
17 words
A process according to claim 4 wherein said treatment is conducted between 120° C. and 160° C.
Claim 17
Dependent Claim
17 words
A process according to claim 15 wherein said reaction time is between 30 minutes and 30 hours.
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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) | 1992-09-11 | 1993-03-13 | 1993-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-11 | 1997-03-13 | 1997-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-11 | 2001-03-13 | 2001-09-12 | $7700.00 | Window Closed / Lapsed |