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US4876358A
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Oxyethylene bismaleimide derivatives
Assignee: Huntsman Corp
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Filing: 1987-11-25
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Granted: 1989-10-24
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Expires: 2007-11-25
Abstract
Abstract Novel bismaleimides of the formula ##STR1## wherein n=1, 2, or 3 are formed in two steps by reacting a diamine and maleic anhydride to form a bismaleamic acid which is reacted with acetic anhydride in the presence of acetone to form the bismaleimide. The bismaleimide monomer and prepolymers and the polybismaleimides formed from them may have improved flexibility, processibility, toughness and solubility.
Inventors
- 👤 David C. Alexander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:09
CPC Classifications
C; C07; C07D; C07D207/00; C07D207/02; C07D207/44; C07D207/444; C07D207/448; C07D207/452; C08; C08G; C08G65/00; C08G65/02; C08G65/32; C08G65/329; C08G65/333; C08G65/33331; C08G65/33337; C08G65/33396
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
26 words
A liquid bismaleimidoaspartimide prepolymer comprising 60 to 90 weight percent bismaleimide of the formula: ##STR11## wherein n=2 and 10 to 40 weight percent triethylene glycol diamine.
Claim 2
Dependent Claim
26 words
A liquid bismaleimidoaspartimide prepolymer comprising 60 to 90 weight percent bismaleimide of the formula: ##STR11## wherein n=2 and 10 to 40 weight percent triethylene glycol diamine.
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) | 1992-10-23 | 1993-04-24 | 1993-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-23 | 1997-04-24 | 1997-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-23 | 2001-04-24 | 2001-10-24 | $7700.00 | Window Closed / Lapsed |