Patent US2597440A successfully refreshed from Google Patents.
US2597440A
Expired / Lapsed
US
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Strongly basic anion-exchange resins
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
2026-10-23 13:23
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/44
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
95 words
A PROCESS FOR PREPARING SOLID, WATER-INSOLUBLE, ANION-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 CHLOROMETHYLATING THE RESULTANT PROLIFEROUS POLYMER WHEREBY CHLOROMETHYL GROUPS ARE ATTACHED TO THE AROMATIC NUCLEI IN AN AMOUNT EQUAL TO AT LEAST ONE CHLORMETHYL GROUP FOR EVERY FIFTEEN AROMATIC NUCLEI IN SAID PROLIFEROUS POLYMER, REACTING THE RESULTANT CHLOROMETHYLATED PROLIFEROUS POLYMER WITH A TERTIARY AMINE, AND THEREAFTER ISOLATING THE RESULTANT ANION-EXCHANGE RESIN.
Claim 2
Dependent Claim
95 words
A PROCESS FOR PREPARING SOLID, WATER-INSOLUBLE, ANION-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 CHLOROMETHYLATING THE RESULTANT PROLIFEROUS POLYMER WHEREBY CHLOROMETHYL GROUPS ARE ATTACHED TO THE AROMATIC NUCLEI IN AN AMOUNT EQUAL TO AT LEAST ONE CHLORMETHYL GROUP FOR EVERY FIFTEEN AROMATIC NUCLEI IN SAID PROLIFEROUS POLYMER, REACTING THE RESULTANT CHLOROMETHYLATED PROLIFEROUS POLYMER WITH A TERTIARY AMINE, AND THEREAFTER ISOLATING THE RESULTANT ANION-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 |