US4128568A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the continuous preparation of polydiorganosiloxanes
Assignee: Momentive Performance Materials GmbH
•
Filing: 1978-02-02
•
Granted: 1978-12-05
•
Expires: 1998-02-02
Abstract
Abstract A process for the production of polymeric organosiloxanes comprising reacting diorganosiloxanes with substances regulating the chain length in the presence of alkaline and/or acid reaction catalysts and wherein the polymerization takes place in a reactor consisting of several zones and is provided with stirring or conveying elements, the arrangement of the stirring or conveying elements being such that the flow of material produced by the stirring or conveying element in each zone is the opposite of that in the adjacent zone or zones.
Inventors
- 👤 Werner Buchner
- 👤 Bruno Degen
- 👤 Ludwig Fries
- 👤 Judat Helmut
- 👤 Rudolf Mundil
- 👤 Karl-Heinz Rudolph
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:07
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/04; C08G77/06
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
98 words
In a process for the continuous production of high polymer viscous organosiloxanes comprising reacting diorganosiloxanes with substances regulating the chain length in the presence of alkaline or acid catalysts and wherein the reactants are mixed mechanically and wherein the reaction takes place in a reactor which consists of several zones and which is provided with stirring or conveying elements the improvement which comprises that the arrangement of the stirring or conveying elements being such that the flow of material produced by the stirring or conveying element in each zone is the opposite of that in the adjacent zone.
Claim 2
Dependent Claim
98 words
In a process for the continuous production of high polymer viscous organosiloxanes comprising reacting diorganosiloxanes with substances regulating the chain length in the presence of alkaline or acid catalysts and wherein the reactants are mixed mechanically and wherein the reaction takes place in a reactor which consists of several zones and which is provided with stirring or conveying elements the improvement which comprises that the arrangement of the stirring or conveying elements being such that the flow of material produced by the stirring or conveying element in each zone is the opposite of that in the adjacent zone.
Claim 3
Dependent Claim
39 words
A process as claimed in claim 1 wherein the stirrers are mounted in one or more shafts which rotate about their longitudinal axes within the reactor, said axes being coaxial with or parallel to the axis of the reactor.
Claim 4
Dependent Claim
18 words
A process as claimed in claim 1 wherein the reactor consists of about 5 to about 30 zones.
Claim 5
Dependent Claim
13 words
A process as claimed in claim 1 wherein said diorganosiloxanes are cyclic diorganosiloxanes.
Claim 6
Dependent Claim
51 words
A process as claimed in claim 3 wherein the cyclic diorganosiloxane is one of the general formula ##STR4## wherein, R and R 1 each independently represent an optionally substituted alkyl or alkenyl radical, a vinyl radical or an optionally substituted aryl radical, and x is an integer from 3 to 8.
References Cited (Backward Citations)
US3803195A
Cited
US3903047A
Cited
US3853934A
Cited
US3853933A
Cited
US3939195A
Cited
US3978104A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-12-04 | 1982-06-05 | 1982-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-04 | 1986-06-05 | 1986-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-04 | 1990-06-05 | 1990-12-05 | $7700.00 | Window Closed / Lapsed |