US4053696A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of vinylpyrrolidone polymers
Assignee: BASF SE
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Filing: 1975-11-17
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Granted: 1977-10-11
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Expires: 1995-11-17
Abstract
Abstract A process for the continuous manufacture of vinylpyrrolidone polymers of low K values, wherein vinylpyrrolidone, with or without comonomers copolymerizable therewith, is polymerized in organic solvents at elevated temperatures and superatmospheric pressures in the presence of a source of free radicals.
Inventors
- 👤 Karl Herrle
- 👤 Hermann Gausepohl
- 👤 Wolfgang Schwarz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:37
CPC Classifications
C; C08; C08F; C08F26/00; C08F26/06; C08F26/10
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
131 words
A process for the continuous manufacture of polyvinylpyrrolidone having a K value of from 10 to 35 which comprises: continuously polymerizing a monomer consisting essentially of vinylpyrrolidone in at least one continuous polymerization zone at a temperature of from 100° to 300° C., in the presence of from 0.1 to 5% by weight, based on said monomer, of a free radical initiator selected from the group consisting of dicumyl peroxide, di-tert.-butyl peroxide and 2,2di-tert.-butyl peroxybutane, and in an organic solvent selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, dioxane, tetrahydrofuran, chloroform, methylene chloride, tetrachloroethane, hexachloroethane, xylene, cumene, alkylbenzenes or mixtures thereof, said continuous polymerization being carried out at a pressure greater than 1 bar and within a residence time in the polymerization zone of about 3 to 120 minutes.
Claim 2
Dependent Claim
131 words
A process for the continuous manufacture of polyvinylpyrrolidone having a K value of from 10 to 35 which comprises: continuously polymerizing a monomer consisting essentially of vinylpyrrolidone in at least one continuous polymerization zone at a temperature of from 100° to 300° C., in the presence of from 0.1 to 5% by weight, based on said monomer, of a free radical initiator selected from the group consisting of dicumyl peroxide, di-tert.-butyl peroxide and 2,2di-tert.-butyl peroxybutane, and in an organic solvent selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, dioxane, tetrahydrofuran, chloroform, methylene chloride, tetrachloroethane, hexachloroethane, xylene, cumene, alkylbenzenes or mixtures thereof, said continuous polymerization being carried out at a pressure greater than 1 bar and within a residence time in the polymerization zone of about 3 to 120 minutes.
Claim 3
Dependent Claim
30 words
A process as claimed in claim 1 wherein the concentration of said vinylpyrrolidone monomer in said organic solvent, based on the weight of the solution, is from 5 to 75%.
Claim 4
Dependent Claim
20 words
A process as claimed in claim 1 wherein the polymerization is carried out in two or more successive polymerization zones.
Claim 5
Dependent Claim
18 words
A process as claimed in claim 1 carried out at a temperature of from 140° to 220° C.
Claim 6
Dependent Claim
23 words
A process as claimed in claim 1 carried out to yield a vinylpyrrolidone homopolymer having a K value of from 12 to 25.
Claim 7
Dependent Claim
18 words
A process as claimed in claim 1 carried out at a pressure of from 2 to 100 bars.
Claim 8
Dependent Claim
18 words
A process as claimed in claim 1 carried out at a pressure of from 5 to 45 bars.
Claim 9
Dependent Claim
18 words
A process as claimed in claim 1 carried out within a residence time of 5 to 50 minutes.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-10 | 1981-04-11 | 1981-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-10 | 1985-04-11 | 1985-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-10 | 1989-04-11 | 1989-10-11 | $7700.00 | Window Closed / Lapsed |