US4952670A
Expired / Lapsed
US
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Polymeric hydridothiosilazanes, processes for the preparation thereof, silicon nitride-containing ceramic materials which can be prepared therefrom, and the preparation thereof
Assignee: Hoechst AG
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Filing: 1988-12-22
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Granted: 1990-08-28
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Expires: 2008-12-22
Abstract
Abstract Polymeric hydridothiosilazanes, processes for the preparation thereof, silicon nitride-containing ceramic materials which can be prepared therefrom, and the preparation thereof. The invention relates to novel polymeric hydridothiosilazanes, the preparation thereof, the conversion thereof into silicon nitride-containing ceramic material, and this material itself. To prepare the polymeric hydridothiosilazanes, oligohydridoalkylsilazanes (RSiHNH) n are reacted with elemental sulfur and ether as solvents. The polymeric hydridothiosilazanes can then be pyrolyzed to form silicon nitride-containing ceramic material.
Inventors
- 👤 Tilo Vaahs
- 👤 Hans-Jerg Kleiner
- 👤 Marcellus Peuckert
- 👤 Martin Bruck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:44
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/60; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/589
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
54 words
A process for the preparation of a polymeric hydridothiosilazane, which comprises reacting an oligohydridoalkylsilazane of the formula (RSiHNH) n in which n is approximately 3 to 12 and R is C 1 -C 6 -alkyl or C 2 -C 6 alkenyl, with elemental sulfur in an ether as solvent at 30° to 120° C.
Claim 2
Dependent Claim
54 words
A process for the preparation of a polymeric hydridothiosilazane, which comprises reacting an oligohydridoalkylsilazane of the formula (RSiHNH) n in which n is approximately 3 to 12 and R is C 1 -C 6 -alkyl or C 2 -C 6 alkenyl, with elemental sulfur in an ether as solvent at 30° to 120° C.
Claim 3
Dependent Claim
53 words
A process for the preparation of a polymeric hydridothiosilazane, which comprises reacting an oligohydridoalkylsilazane obtained by reacting a dichlorohydridoalkylsilane RSiHCl 2 with NH 3 , with elemental sulfur in an ether as a solvent at 30° to 120° C., where R is C 1 -C 6 -alkyl or C 2 -C 6 -alkenyl.
Claim 4
Dependent Claim
53 words
A process for the preparation of a polymeric hydridothiosilazane, which comprises reacting an oligohydridoalkylsilazane obtained by reacting a dichlorohydridoalkylsilane RSiHCl 2 with NH 3 , with elemental sulfur in an ether as a solvent at 30° to 120° C., where R is C 1 -C 6 -alkyl or C 2 -C 6 -alkenyl.
Claim 5
Dependent Claim
15 words
The process as claimed in claim 1 or 2, wherein R is methyl or vinyl.
Claim 6
Dependent Claim
24 words
The process as claimed in claim 1, wherein the molar ratio between sulfur and an RSiHNH unit of the oligohydridoalkylsilazane is 0.1:1 to 1:1.
Claim 7
Dependent Claim
36 words
A polymeric hydriodothiosilazane of the formula ##STR4## where R is C 1 -C 6 -alkyl or C 2 -C 6 -alkenyl and x and y denote the molar fractions of the two structural, and x+y=1 units.
Claim 8
Dependent Claim
36 words
A polymeric hydriodothiosilazane of the formula ##STR4## where R is C 1 -C 6 -alkyl or C 2 -C 6 -alkenyl and x and y denote the molar fractions of the two structural, and x+y=1 units.
Claim 9
Dependent Claim
14 words
A polymeric hydriodothiosilazane as claimed in claim 5, wherein y is 0.6 to 0.8.
Claim 10
Dependent Claim
14 words
A polymeric hydriodothiosilazane as claimed in claim 5, wherein R is methyl or vinyl.
Claim 11
Dependent Claim
12 words
A polymeric hydridothiosilazane obtainable by the process as claimed in claim 1.
References Cited (Backward Citations)
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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) | 1993-08-27 | 1994-02-26 | 1994-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-27 | 1998-02-26 | 1998-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-27 | 2002-02-26 | 2002-08-28 | $7700.00 | Window Closed / Lapsed |