US3915909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of rubber as a powder from its aqueous dispersion
Assignee: Bayer AG
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Filing: 1974-06-18
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Granted: 1975-10-28
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Expires: 1994-06-18
Abstract
Abstract A process for isolating rubbers from their aqueous dispersions (latices), wherein a cellulose ether is added to an aqueous rubber dispersion in a quantity of 0.1 to 10 % by weight, based on the rubber, and a water-soluble alkali metal, alkaline earth metal, aluminium or zinc salt is added in a quantity of 0.02 to 10 % by weight, based on the rubber and the water is removed from this mixture.
Inventors
- 👤 Hildegard Schnoring
- 👤 Gottfried Pampus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:14
CPC Classifications
C; C08; C08C; C08C1/00; C08C1/14; C08C1/16
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
180 words
A PROCESS FOR RECOVERING A ITS AQUEOUS DISPERSION, SAID RUBBER BEING SELECTED FROM THE GROUP CONSISTING OF POLYMERS OF DIENES, POLYMERS OF ETHYLENE, POLYMERS OF PROPYLENE, ETHYLENEPROPYLENE TERPOLYMERS AND POLYALKENAMERS, SAID PROCESS COMPRISING ADDING TO THE AQUEOUS DISPERSION OF SAID RUBBER 0.1 TO 10% BY WEIGHT OF A CELLULOSE ETHER SELECTED FROM THE GROUP CONSISTING OF A C1-C4 ALKYL CELLULOSE, A HYDROXY C2-C10 ALKYL CELLULOSE AND SAID HYDROXY C2-C10 ALKYL CELLULOSE HAVING AT LEAST ONE CH2 GROUP REPLACED BY -0-AND 0.02 TO 10% BY WEIGHT OF A SALT SELECTED FROM THE GROUP CONSISTING OF WATER-SOLUBLE ALKALI METAL SALTS WATER-SOLUBLE ALKALINE EARTH METAL SALTS, WATER-SOLUBLE ALUMINUM SALTS AND WATERSOLUBLE ZINC SALTS SAD PERCENTAGES BEING BASED ON THE WEIGHT OF RUBBER IN SAID AQUEOUS DISPERSION THEREOF AND THERE BEING FROM 20 TO 100 PARTS BY WEIGHT OF SAID SELECTED SALT PER 100 PARTS OF SAID SELECTED CELLULOSE ETHER, MIXING SAID AQUEOUS DISPERSION OF SAID RUBBER, SAID SELECTED CELLULOSE ETHER AND SAID SELECTED WATER-SOLUBLE SALT WITH WATER UNTIL THE RUBBER OF SAID AQUEOUS DISPERSION COAGULATES, SEPARATING RESULTING COAGULATE AND DRYING SAID SEPARATED COAGULATE.
Claim 2
Dependent Claim
180 words
A PROCESS FOR RECOVERING A ITS AQUEOUS DISPERSION, SAID RUBBER BEING SELECTED FROM THE GROUP CONSISTING OF POLYMERS OF DIENES, POLYMERS OF ETHYLENE, POLYMERS OF PROPYLENE, ETHYLENEPROPYLENE TERPOLYMERS AND POLYALKENAMERS, SAID PROCESS COMPRISING ADDING TO THE AQUEOUS DISPERSION OF SAID RUBBER 0.1 TO 10% BY WEIGHT OF A CELLULOSE ETHER SELECTED FROM THE GROUP CONSISTING OF A C1-C4 ALKYL CELLULOSE, A HYDROXY C2-C10 ALKYL CELLULOSE AND SAID HYDROXY C2-C10 ALKYL CELLULOSE HAVING AT LEAST ONE CH2 GROUP REPLACED BY -0-AND 0.02 TO 10% BY WEIGHT OF A SALT SELECTED FROM THE GROUP CONSISTING OF WATER-SOLUBLE ALKALI METAL SALTS WATER-SOLUBLE ALKALINE EARTH METAL SALTS, WATER-SOLUBLE ALUMINUM SALTS AND WATERSOLUBLE ZINC SALTS SAD PERCENTAGES BEING BASED ON THE WEIGHT OF RUBBER IN SAID AQUEOUS DISPERSION THEREOF AND THERE BEING FROM 20 TO 100 PARTS BY WEIGHT OF SAID SELECTED SALT PER 100 PARTS OF SAID SELECTED CELLULOSE ETHER, MIXING SAID AQUEOUS DISPERSION OF SAID RUBBER, SAID SELECTED CELLULOSE ETHER AND SAID SELECTED WATER-SOLUBLE SALT WITH WATER UNTIL THE RUBBER OF SAID AQUEOUS DISPERSION COAGULATES, SEPARATING RESULTING COAGULATE AND DRYING SAID SEPARATED COAGULATE.
Claim 3
Dependent Claim
31 words
The process of claim 1 wherein said selected cellulose ether and said selected water-soluble salt are added to the aqueous dispersion of said rubber in the form of an aqueous dispersion.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |