Patent US3972939A successfully refreshed from Google Patents.
US3972939A
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Process for the preparation of polyethylene-polyamine salts of low viscosity
Assignee: Bayer AG
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Filing: 1974-10-09
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Granted: 1976-08-03
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Expires: 1994-10-09
Abstract
Abstract Polyethylene-polyamine salts of low viscosity and high retention action, are prepared by subjecting polyethylene-polyamine salts of higher viscosity to a thermal degradation by heating their aqueous solutions in closed reaction vessels to temperatures of 100° to 180° C under pressures of 2 to 10 atmospheres.
Inventors
- 👤 Georg Spielberger
- 👤 Knut Hammerstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:11
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/54; C08; C08G; C08G73/00; C08G73/02; C08G73/0206; D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/54; D21H17/56
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
85 words
A process for preparing a polyethylene-polyamine salt of relatively low viscosity and high retention action comprising subjecting a polyethylene polyamine salt, of a viscosity of 900-10,000 cp at 25° C in substantially 25% strength aqueous solution and having high retention action, to thermal degradation by heating its aqueous solutions in a closed reaction vessel at 100°-180° C and at a pressure of 2-10 atmospheres, thereby reducing the viscosity of said salt to a viscosity of 300-600 cp at 25° C in substantially 25% aqueous solution.
Claim 2
Dependent Claim
85 words
A process for preparing a polyethylene-polyamine salt of relatively low viscosity and high retention action comprising subjecting a polyethylene polyamine salt, of a viscosity of 900-10,000 cp at 25° C in substantially 25% strength aqueous solution and having high retention action, to thermal degradation by heating its aqueous solutions in a closed reaction vessel at 100°-180° C and at a pressure of 2-10 atmospheres, thereby reducing the viscosity of said salt to a viscosity of 300-600 cp at 25° C in substantially 25% aqueous solution.
Claim 3
Dependent Claim
12 words
A process according to claim 1 wherein the temperature is 105°-120° C.
Claim 4
Dependent Claim
24 words
A process according to claim 1 wherein the viscosity of the polyethylene polyamine salt of reduced viscosity is subsequently raised by addition of dichloroethane.
References Cited (Backward Citations)
US3751474A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-03 | 1980-02-02 | 1980-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-03 | 1984-02-02 | 1984-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-03 | 1988-02-02 | 1988-08-03 | $7700.00 | Window Closed / Lapsed |