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US2640819A
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Process for polymerizing styrene and maleic compounds
Assignee: Monsanto Chemicals Ltd
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Filing: 1950-04-29
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Granted: 1953-06-02
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Expires: 1970-04-29
Abstract
No abstract record available.
Inventors
- 👤 Gerald R Barrett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:26
CPC Classifications
C; C08; C08F; C08F222/00; C08F222/04; C08F222/06; C08F222/08; C08F222/10; C08F222/12; C08F222/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
102 words
A PROCESS OF MASS POLYMERIZING STYRENE AND MALEIC COMPOUNDS WHICH COMPRISES SUBJECTING A MIXTURE OF STYRENE AND A MALEIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF MALEIC ANHYDRIDE, ALKYL HALF ESTERS OF MALEIC ACID AND MIXTURES OF SAID ANHYDRIDE AND SAID ESTERS TO FREE RADICAL INDUCING CONDITIONS IN THE PRESENCE OF FROM ABOUT 0.01 TO TO 2% BY WEIGHT, BASED ON THE MONOMERS IN THE MIXTURE, OF 2,5 DITERTIARY BUTYL PARABENZOQUINONE UNTIL THE RESULTING MASS IS SUBSTANTIALLY FREE OF UNREACTED STYRENE AND MALEIC COMPOUND, SAID STYRENE AND MALEIC COMPOUND BEING PRESENT IN SAID MIXTURE IN A MOL RATIO BETWEEN 1:1 AND 1.5:1.
Claim 2
Dependent Claim
102 words
A PROCESS OF MASS POLYMERIZING STYRENE AND MALEIC COMPOUNDS WHICH COMPRISES SUBJECTING A MIXTURE OF STYRENE AND A MALEIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF MALEIC ANHYDRIDE, ALKYL HALF ESTERS OF MALEIC ACID AND MIXTURES OF SAID ANHYDRIDE AND SAID ESTERS TO FREE RADICAL INDUCING CONDITIONS IN THE PRESENCE OF FROM ABOUT 0.01 TO TO 2% BY WEIGHT, BASED ON THE MONOMERS IN THE MIXTURE, OF 2,5 DITERTIARY BUTYL PARABENZOQUINONE UNTIL THE RESULTING MASS IS SUBSTANTIALLY FREE OF UNREACTED STYRENE AND MALEIC COMPOUND, SAID STYRENE AND MALEIC COMPOUND BEING PRESENT IN SAID MIXTURE IN A MOL RATIO BETWEEN 1:1 AND 1.5:1.
References Cited (Backward Citations)
US2047398A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-01 | 1956-12-01 | 1957-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-01 | 1960-12-01 | 1961-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-01 | 1964-12-01 | 1965-06-02 | $7700.00 | Window Closed / Lapsed |