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Patent US2546238A successfully refreshed from Google Patents.
US2546238A
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Inhibition of acrylonitrile polymerization
Assignee: EIDP Inc
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Filing: 1947-02-18
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Granted: 1951-03-27
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Expires: 1967-02-18
Abstract
No abstract record available.
Inventors
- 👤 Richards John Cadwallader
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:03
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/38; C08F2/12; C08F2/16; C08F20/00; C08F20/02; C08F20/42; C08F20/44
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
57 words
IN THE POLYMERIZATIONS OF ACRYLONITRILE TO POLYMERS CONTAINING AT LEAST 85% ACRYLONITRILE, A PROCESS FOR SUBSTANTIALLY STOPPING SAID POLYMERIZATIONS, WHICH COMPRISES ADJUSTING THE POLYMERIZATION SYSTEMS, DURING POLYMERIZATION TO A PH FROM 6.0 TO 10.0, THE SAID SYSTEMS CONTAINING A PERSULFATE CATALYST AND A BISULFITE ACTIVATOR AND BEING HEATED TO A TEMPERATURE FROM 30* C TO 50* C.
Claim 2
Dependent Claim
57 words
IN THE POLYMERIZATIONS OF ACRYLONITRILE TO POLYMERS CONTAINING AT LEAST 85% ACRYLONITRILE, A PROCESS FOR SUBSTANTIALLY STOPPING SAID POLYMERIZATIONS, WHICH COMPRISES ADJUSTING THE POLYMERIZATION SYSTEMS, DURING POLYMERIZATION TO A PH FROM 6.0 TO 10.0, THE SAID SYSTEMS CONTAINING A PERSULFATE CATALYST AND A BISULFITE ACTIVATOR AND BEING HEATED TO A TEMPERATURE FROM 30* C TO 50* 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) | 1954-03-26 | 1954-09-25 | 1955-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-03-26 | 1958-09-25 | 1959-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-03-26 | 1962-09-25 | 1963-03-27 | $7700.00 | Window Closed / Lapsed |