Patent US4900448A successfully refreshed from Google Patents.
Patent US2597438A successfully refreshed from Google Patents.
US2597438A
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Cation-exchange polymers of the sulfonic type
Assignee: Rohm and Haas Co
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Filing: 1951-05-12
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Granted: 1952-05-20
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Expires: 1971-05-12
Abstract
No abstract record available.
Inventors
- 👤 George W Bodamer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 10:02
CPC Classifications
B; B01; B01J; B01J39/00; B01J39/08; B01J39/16; B01J39/18; B01J39/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
57 words
A PROCESS FOR PREPARING SOLID, WATER-INSOLUBLE, CATION-EXCHANGE RESINS WHICH COMPRISES PROLIFEROUSLY POLYMERIZING STYRENE AT A TEMPERATURE FROM ABOUT 20* C. TO ABOUT 80* C. IN THE SUBSTANTIALLY COMPLETE ABSENCE OF OXYGEN AND IN THE PRESENCE OF A SEED OF A PREVIOUSLY PREPARED PROLIFEROUS POLYMER, THEN SULFONATING THE RESULTANT PROLIFEROUS POLYMER, AND THEREAFTER ISOLATING THE RESULTANT CATION-EXCHANGE RESIN.
Claim 2
Dependent Claim
57 words
A PROCESS FOR PREPARING SOLID, WATER-INSOLUBLE, CATION-EXCHANGE RESINS WHICH COMPRISES PROLIFEROUSLY POLYMERIZING STYRENE AT A TEMPERATURE FROM ABOUT 20* C. TO ABOUT 80* C. IN THE SUBSTANTIALLY COMPLETE ABSENCE OF OXYGEN AND IN THE PRESENCE OF A SEED OF A PREVIOUSLY PREPARED PROLIFEROUS POLYMER, THEN SULFONATING THE RESULTANT PROLIFEROUS POLYMER, AND THEREAFTER ISOLATING THE RESULTANT CATION-EXCHANGE RESIN.
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) | 1955-05-20 | 1955-11-19 | 1956-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-05-20 | 1959-11-19 | 1960-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-05-20 | 1963-11-19 | 1964-05-20 | $7700.00 | Window Closed / Lapsed |