US5196559A
Expired / Lapsed
US
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Equilibration of cyclic siloxanes with novel catalysts
Assignee: Dow Silicones Corp
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Filing: 1992-01-23
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Granted: 1993-03-23
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Expires: 2012-01-23
Abstract
Abstract A process for preparing cyclosiloxanes by the redistribution of a cyclosiloxane or mixture of cyclosiloxanes in the presence of a rearrangement catalyst.
Inventors
- 👤 William J. Schulz, Jr.
- 👤 Joseph B. Lambert
- 👤 Lidia Kania
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:19
CPC Classifications
C; C07; C07F; C07F7/00; C07F7/02; C07F7/08; C07F7/0834; C07F7/0838; C07F7/0872; C07F7/0874; C07F7/18; C07F7/21
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
33 words
A process, said process comprising, contacting at least one cyclic siloxane with at least one catalyzing organosilicon compound at a temperature and a time sufficient to redistribute said cyclic siloxane under anhydrous conditions.
Claim 2
Dependent Claim
33 words
A process, said process comprising, contacting at least one cyclic siloxane with at least one catalyzing organosilicon compound at a temperature and a time sufficient to redistribute said cyclic siloxane under anhydrous conditions.
Claim 3
Dependent Claim
122 words
A process, said process comprising, contacting at least one cyclic siloxane having the general formula (R 2 SiO)x with a catalyzing organosilicon compound having the general formulas (R' 3 SiA) and ##STR4## at a temperature from -78° C. to 80° C.; and for a time of 1 to 72 hours under anhydrous conditions wherein R' and R" are selected from the group comprising alkyl, aryl, aralkyl, alkenyl, haloalkyl, thioalkyl, diakylamino, diarylamino, alkylarylamino, thioaryl, alkoxy, aryloxy, and alkaryl groups having one to sixteen carbon atoms; and R and R" are hydrogen or R'; x is an integer having a value of from three to twelve; n is an integer having a value of from two to seven; and A is a non-nucleophilic anion.
Claim 4
Dependent Claim
122 words
A process, said process comprising, contacting at least one cyclic siloxane having the general formula (R 2 SiO)x with a catalyzing organosilicon compound having the general formulas (R' 3 SiA) and ##STR4## at a temperature from -78° C. to 80° C.; and for a time of 1 to 72 hours under anhydrous conditions wherein R' and R" are selected from the group comprising alkyl, aryl, aralkyl, alkenyl, haloalkyl, thioalkyl, diakylamino, diarylamino, alkylarylamino, thioaryl, alkoxy, aryloxy, and alkaryl groups having one to sixteen carbon atoms; and R and R" are hydrogen or R'; x is an integer having a value of from three to twelve; n is an integer having a value of from two to seven; and A is a non-nucleophilic anion.
Claim 5
Dependent Claim
11 words
The process of claim 2, wherein each alkyl group is methyl.
Claim 6
Dependent Claim
13 words
The process of claim 2, wherein R is methyl and R' is phenyl.
Claim 7
Dependent Claim
15 words
The process of claim 2, wherein the temperature range is 25° C. to 80° C.
Claim 8
Dependent Claim
15 words
The process of claim 2, wherein the temperature is from 25° C. to 50° C.
Claim 9
Dependent Claim
14 words
The process of claim 2, wherein the time is from 2 to 50 hours.
Claim 10
Dependent Claim
14 words
The process of claim 2, wherein the time is from 2 to 30 hours.
Claim 11
Dependent Claim
11 words
The process of claim 2, wherein additionally a solvent is present.
Claim 12
Dependent Claim
14 words
The process of claim 9, wherein said solvent is CH 2 Cl 2 .
Claim 13
Dependent Claim
12 words
The process of claim 9, wherein said solvent is CH 3 CN.
Claim 14
Dependent Claim
17 words
The process of claim 2, wherein the siloxanes (R 2 SiO)x are a mixture of cyclic siloxanes.
Claim 15
Dependent Claim
21 words
The process of claim 2, wherein the concentration of R' 3 SiA is 10 -5 to 10 -2 moles per liter.
Claim 16
Dependent Claim
15 words
The process of claim 2, wherein the contact takes place using an inert gas atmosphere.
Claim 17
Dependent Claim
21 words
The process of claim 14, wherein the said gas is selected from a group consisting essentially of argon, nitrogen and helium.
Claim 18
Dependent Claim
15 words
The process of claim 2, wherein R' 3 SiA is PhMe 2 SiClO 4 .
Claim 19
Dependent Claim
7 words
The process of claim 2, wherein ##STR5##
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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) | 1996-03-22 | 1996-09-21 | 1997-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-03-22 | 2000-09-21 | 2001-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-03-22 | 2004-09-21 | 2005-03-23 | $7700.00 | Window Closed / Lapsed |