US2983717A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymerization process for watersoluble polymers
Assignee: Wyeth Holdings LLC
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Filing: 1957-07-25
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Granted: 1961-05-09
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Expires: 1977-07-25
Abstract
No abstract record available.
Inventors
- 👤 Ernest J Henley
- 👤 Robert C Bell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:27
CPC Classifications
C; C08; C08F; C08F4/00; C08F20/00; C08F20/62
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
188 words
A METHOD OF PREPARING WATER-SOLUBLE POLYMERS WHICH COMPRISES POLYMERIZING IN AQUEOUS SOLUTION MONOMERIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF ACRYLAMIDE, METHACRYLAMIDE, ACRYLIC ACID AND METHACRYLIC ACID AND WATER-SOLUBLE MIXTURES THEREOF WITH NOT MORE THAN 25% OF A MONOETHYLENICALLY UNSATURATED MONOMER COPOLYMERIZABLE THEREWITH BY DISPERSING INTO SAID AQUEOUS SOLUTION OF MONOMERIC MATERIAL FROM ABOUT 0.001 TO ABOUT 0.5% OF A REDOX CATALYST, THE OXIDIZING COMPONENT A AND THE REDUCING COMPONENT B OF SAID CATALYST BEING PRESENT IN APPROXIMATELY STOICHIOMETRICALLY EQUIVALENT AMOUNTS, AND ADDITIONALLY DISPERSING IN SAID SOLUTION AN AMOUNT OF BETWEEN ABOUT 0.5 TO 4 TIMES THE AMOUNT OF SAID REDOX CATALYST, OF THE OXIDIZING COMPONENT A BUT NO FURTHER AMOUNT OF THE REDUCING COMPONENT B, SAID A COMPONENT HAVING A POLYMERIZATION ACTIVATION TEMPERATURE HIGHER THAN THE STOICHIOMETRICALLY EQUIVALENT FRACTION OF SAID CATALYST WHICH COMBINES WITH B, THEREBY BEING ACTIVATED AT AN ADVANCED STAGE OF THE POLYMERIZATION REACTION; AND EFFECTING POLYMERIZATION OF SAID MONOMERIC MATERIAL WITH NO ADDITIONAL AMOUNTS OF CATALYST BY INITIATING THE POLYMERIZATION AT A TEMPERATURE BETWEEN ABOUT 35*C. AND 55*C. AND COMPLETING THE ADVANCED STAGE OF THE POLYMERIZATION AT A TEMPERATURE HIGHER THAN ABOUT 65*C.
Claim 2
Independent Claim
188 words
A METHOD OF PREPARING WATER-SOLUBLE POLYMERS WHICH COMPRISES POLYMERIZING IN AQUEOUS SOLUTION MONOMERIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF ACRYLAMIDE, METHACRYLAMIDE, ACRYLIC ACID AND METHACRYLIC ACID AND WATER-SOLUBLE MIXTURES THEREOF WITH NOT MORE THAN 25% OF A MONOETHYLENICALLY UNSATURATED MONOMER COPOLYMERIZABLE THEREWITH BY DISPERSING INTO SAID AQUEOUS SOLUTION OF MONOMERIC MATERIAL FROM ABOUT 0.001 TO ABOUT 0.5% OF A REDOX CATALYST, THE OXIDIZING COMPONENT A AND THE REDUCING COMPONENT B OF SAID CATALYST BEING PRESENT IN APPROXIMATELY STOICHIOMETRICALLY EQUIVALENT AMOUNTS, AND ADDITIONALLY DISPERSING IN SAID SOLUTION AN AMOUNT OF BETWEEN ABOUT 0.5 TO 4 TIMES THE AMOUNT OF SAID REDOX CATALYST, OF THE OXIDIZING COMPONENT A BUT NO FURTHER AMOUNT OF THE REDUCING COMPONENT B, SAID A COMPONENT HAVING A POLYMERIZATION ACTIVATION TEMPERATURE HIGHER THAN THE STOICHIOMETRICALLY EQUIVALENT FRACTION OF SAID CATALYST WHICH COMBINES WITH B, THEREBY BEING ACTIVATED AT AN ADVANCED STAGE OF THE POLYMERIZATION REACTION; AND EFFECTING POLYMERIZATION OF SAID MONOMERIC MATERIAL WITH NO ADDITIONAL AMOUNTS OF CATALYST BY INITIATING THE POLYMERIZATION AT A TEMPERATURE BETWEEN ABOUT 35*C. AND 55*C. AND COMPLETING THE ADVANCED STAGE OF THE POLYMERIZATION AT A TEMPERATURE HIGHER THAN ABOUT 65*C.
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) | 1964-05-08 | 1964-11-07 | 1965-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-05-08 | 1968-11-07 | 1969-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-05-08 | 1972-11-07 | 1973-05-09 | $7700.00 | Window Closed / Lapsed |