Process for the preparation of bis-maleimides
Abstract
Abstract 1. IN A PROCESS FOR THE PREPARATION OF BIS-MALEIMIDES, WHICH COMPRISES EFFECTING REACTION BETWEEN A BIS-MALEAMIC ACID WHICH HAS THE GENERAL FORMULA HOOC-CH=CH-CO-NH-D-NH-CO-CH=CH-COOH IN WHICH D HAS ONE OF THE FOLLOWING MEANINGS: A LINEAR OR BRANCHED ALKYLENE RADICAL OF 2-12 CARBON ATOMS; PHENYLENE; CYCLOHEXYLENE; NAPHTHYLENE; A PLURALITY OF PHENYLENE OR CYCLOHEXYLENE RADICALS LINKED BY A SIMPLE VALENCY BOND OR BY AN ATOM OR GROUP WHICH IS INERT UNDER THE REACTION CONDITIONS; AND A LOWER CARBOXYLIC ACID ANHYDRIDE IN THE PRESENCE OF A TERTIARY AMINE AND AN ORGANIC DILUENT WHICH IS LIQUID UNDER THE REACTION CONDITIONS, THE IMPROVEMENT WHEREIN THE REACTION IS CARRIED OUT IN THE PRESENCE OF A CATALYTIC AMOUNT OF A CATALYST CONSISTING OF A NICKEL SALT OR DIVALENT NICKEL COMPLEX WHICH IS SOLUBLE IN THE LIQUID PHASE OF THE REACTION MIXTURE, FROM 0.2 TO 1 MOLE OF TERTIARY AMINE BEING USED PER MOLE OF BIS-MALEAMIC ACID.
Inventors
- 👤 M Bargain
Bibliographic Details
Claims Analysis
Total Claims: 2References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1977-09-30 | 1978-04-01 | 1978-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-30 | 1982-04-01 | 1982-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-30 | 1986-04-01 | 1986-10-01 | $7700.00 | Window Closed / Lapsed |