US3168500A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gelation of polyacrylamide
Assignee: Wyeth Holdings LLC
•
Filing: 1960-11-25
•
Granted: 1965-02-02
•
Expires: 1980-11-25
Abstract
No abstract record available.
Inventors
- 👤 Tzeng J Suen
- 👤 Donald F Rossler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:54
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/30; Y; Y10; Y10S; Y10S526/00; Y10S526/915
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
46 words
A PROCESS WHICH COMPRISES HEATING AN AQUEOUS SOLUTION OF A WATER-SOLUBLE POLYMER OF ACRYLAMIDE WHICH IS SUBSTANTIALLY FREE FROM MONOMERIC MATERIAL WITH A WATER-SOLUBLE, FREE RADICAL CATALYST AT A TEMPERATURE OF FROM ABOUT 45*C. TO ABOUT 100*C. UNTIL SAID POLYMER IS CONVERTED INTO A WATER-INSOLUBLE GEL.
Claim 2
Dependent Claim
46 words
A PROCESS WHICH COMPRISES HEATING AN AQUEOUS SOLUTION OF A WATER-SOLUBLE POLYMER OF ACRYLAMIDE WHICH IS SUBSTANTIALLY FREE FROM MONOMERIC MATERIAL WITH A WATER-SOLUBLE, FREE RADICAL CATALYST AT A TEMPERATURE OF FROM ABOUT 45*C. TO ABOUT 100*C. UNTIL SAID POLYMER IS CONVERTED INTO A WATER-INSOLUBLE GEL.
Claim 3
Dependent Claim
6 words
A CROSS-LINKED, WATER-INSOLUBLE HOMOPOLYMER OF ACRYLAMIDE.
Claim 4
Dependent Claim
6 words
A CROSS-LINKED, WATER-INSOLUBLE HOMOPOLYMER OF ACRYLAMIDE.
References Cited (Backward Citations)
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Cited
US2628214A
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GB646714A
Cited
US2486192A
Cited
US2901468A
Cited
US2870128A
Cited
US2820777A
Cited
US2960486A
Cited
US3075956A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-02-02 | 1968-08-03 | 1969-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-02-02 | 1972-08-03 | 1973-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-02-02 | 1976-08-03 | 1977-02-02 | $7700.00 | Window Closed / Lapsed |