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Patent US4205151A successfully refreshed from Google Patents.
US4205151A
Expired / Lapsed
US
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Polymeric N-substituted maleimide antioxidants
Assignee: ATK Launch Systems LLC
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Filing: 1977-08-02
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Granted: 1980-05-27
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Expires: 1997-08-02
Abstract
Abstract N-substituted maleimide polymers comprising the recurring structural units: <IMAGE> wherein R and R' independently are lower alkyl groups of from 1 to 5 carbon atoms and n is an integer of from about 2 to about 2,000, are disclosed. Their preparation as well as the preparation of their monomer precursors and the preferred use of the polymers as antioxidants, particularly nonabsorbable food antioxidants, are also disclosed.
Inventors
- 👤 James A. Dale
- 👤 Steve Y. W. Ng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:03
CPC Classifications
A; A23; A23B; A23B2/00; A23B2/70; A23B2/725; A23B2/729; A23B2/762; C; C08; C08F; C08F22/00; C08F22/36; C08F22/40; C11; C11B; C11B5/00; C11B5/0042; C11B5/0057
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
33 words
A polymeric maleimide comprising n ##STR9## units, wherein R and R' independently are lower saturated alkyls of from 1 to 5 carbon atoms and n is an integer from 20 to about 1500.
Claim 2
Dependent Claim
33 words
A polymeric maleimide comprising n ##STR9## units, wherein R and R' independently are lower saturated alkyls of from 1 to 5 carbon atoms and n is an integer from 20 to about 1500.
Claim 3
Dependent Claim
18 words
The polymeric maleimide of claim 1, wherein said polymeric maleimide consists essentially of a homopolymer of repeating ##STR10##
Claim 4
Dependent Claim
14 words
The polymeric maleimide of claim 1, wherein R and R' are each t-butyl groups.
Claim 5
Dependent Claim
14 words
The polymeric maleimide of claim 2, wherein R and R' are each t-butyl groups.
Claim 6
Dependent Claim
29 words
The polymeric maleimide of claim 1, having a molecular size which is too large to permit substantial passage of said polymeric maleimide through the walls of the gastrointestinal tract.
Claim 7
Dependent Claim
25 words
The polymeric maleimide of claim 5, having a molecular weight of from 1,000 to 100,000 as determined by gel permeation chromatography compared to polystyrene references.
Claim 8
Dependent Claim
28 words
The polymeric maleimide of claim 1, additionally comprising from 0.1 to 2.0 parts by weight per part of maleimide of copolymeric component selected from the group of ##STR11##
Claim 9
Dependent Claim
57 words
The process for preparing the polymeric maleimide of claim 1, which comprises contacting an N-substituted maleimide of the formula: ##STR12## wherein R and R' independently are lower saturated alkyl groups of from 1 to 5 carbon atoms with a catalytically effective amount of a material selected from the group consisting of cationic and free radical polymerization initiators.
Claim 10
Dependent Claim
12 words
The process of claim 8, wherein R and R' are tert-butyl groups.
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) | 1983-05-27 | 1983-11-26 | 1984-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-27 | 1987-11-26 | 1988-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-27 | 1991-11-26 | 1992-05-27 | $7700.00 | Window Closed / Lapsed |