Patent US4564683A successfully refreshed from Google Patents.
US4564683A
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Bismaleimide compounds
Assignee: United States Department of Energy
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Filing: 1984-04-10
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Granted: 1986-01-14
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Expires: 2004-04-10
Abstract
Abstract Bismaleimides of the formula ##STR1## wherein R 1 and R 2 each independently is H, C 1-4 -alkyl, C 1-4 -alkoxy, C1 or Br, or R 1 and R 2 together form a fused 6-membered hydrocarbon aromatic ring, with the proviso that R 1 and R 2 are not t-butyl or t-butoxy; X is O, S or Se; n is 1-3; and the alkylene bridging group, optionally, is substituted by 1-3 methyl groups or by fluorine, form polybismaleimide resins which have valuable physical properties. Uniquely, these compounds permit extended cure times, i.e., they remain fluid for a time sufficient to permit the formation of a homogeneous melt prior to curing.
Inventors
- 👤 Johnnie E. Adams
- 👤 Donald R. Jamieson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:47
CPC Classifications
C; C08; C08F; C08F22/00; C08F22/36; C08F22/40; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/12; C08G73/123; C08G73/124; C08G73/125
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
77 words
A bismaleimide of the formula ##STR4## wherein R 1 and R 2 each independently is H, C 1-4 -alkyl, C 1-4 -alkoxy, Cl or Br, or R 1 and R 2 together form a fused 6-membered hydrocarbon aromatic ring, with the proviso that R 1 and R 2 are not t-butyl or t-butoxy; X is O, S or Se; n is 1-3; and the alkylene bridging group, optionally, is substituted by 1-3 methyl groups or by fluorine.
Claim 2
Dependent Claim
77 words
A bismaleimide of the formula ##STR4## wherein R 1 and R 2 each independently is H, C 1-4 -alkyl, C 1-4 -alkoxy, Cl or Br, or R 1 and R 2 together form a fused 6-membered hydrocarbon aromatic ring, with the proviso that R 1 and R 2 are not t-butyl or t-butoxy; X is O, S or Se; n is 1-3; and the alkylene bridging group, optionally, is substituted by 1-3 methyl groups or by fluorine.
Claim 3
Dependent Claim
11 words
A bismaleimide of claim 1 wherein X is S or Se.
Claim 4
Dependent Claim
27 words
A bismaleimide of claim 1 or 2 wherein one of R 1 and R 2 is H and the other is CH 3 , Cl or Br.
Claim 5
Dependent Claim
18 words
A bismaleimide of claim 1 or 2 wherein both R 1 and R 2 are Cl or Br.
Claim 6
Dependent Claim
17 words
A bismaleimide of claim 1 or 2 wherein n is 2 and the alkylene group is unsubstituted.
Claim 7
Dependent Claim
6 words
1,2-bis(2-maleimidophenylthio)ethane, a compound of claim 1.
Claim 8
Dependent Claim
48 words
A process for preparing a compound of claim 1 comprising reacting, at a temperature of 40°-60° C. and in an inert aprotic solvent, maleic anhydride with a diamine of the formula ##STR5## wherein R 1 , R 2 , X and n are as defined in claim 1.
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) | 1989-01-13 | 1989-07-15 | 1990-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-13 | 1993-07-15 | 1994-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-13 | 1997-07-15 | 1998-01-14 | $7700.00 | Window Closed / Lapsed |