US3890272A
Expired / Lapsed
US
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Polymerizing bis-maleimides
Assignee: University of Notre Dame
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Filing: 1973-05-25
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Granted: 1975-06-17
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Expires: 1993-05-25
Abstract
Abstract Processes for preparing polyimides from bis-maleimides are provided. In these processes, a bis-maleimide is polymerized in the presence of a catalytic amount (usually about 0.01 to 5% by weight of the bis-maleimide) of an alkali metal salt of a Bronsted acid. Preferably, the polymerization is also conducted in the presence of a small amount (usually 0.01 to 5% by weight of the bis-maleimide) of an activator for the catalyst. The activator is an aprotic organic compound having a dielectric constant between about 35 and 45. Melt polymerization is preferred at a preferred temperature of 150* to 275*C.
Inventors
- 👤 Alelio Gaetano Francis D
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:23
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/12; C08G73/126; C08G73/125; C08G73/127
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
9 words
A PROCESS FOR CONVERTING A BIS-MALEIMIDE OF THE FORMULA:
Claim 2
Dependent Claim
9 words
A PROCESS FOR CONVERTING A BIS-MALEIMIDE OF THE FORMULA:
Claim 3
Dependent Claim
45 words
The process of claim 1 wherein the polymerization is conducted in the presence of about 0.01 to 5% by weight of the bis-maleimide of an activator for the catalyst, said activator being an aprotic organic compound having a dielectric constant between about 35 and 45.
Claim 4
Dependent Claim
14 words
The process of claim 2 wherein the catalyst and activator are premixed before polymerization.
Claim 5
Dependent Claim
27 words
The process of claim 2 wherein the catalyst is mixed with a portion of bis-maleimide and the activator is mixed with another portion of bis-maleimide before polymerization.
Claim 6
Dependent Claim
18 words
The process of claim 1 wherein the temperature Is in the range of about 150* to 275* C.
Claim 7
Dependent Claim
17 words
The process of claim 2 wherein the temperature is in the range of about 150* to 275*C.
Claim 8
Dependent Claim
20 words
The process of claim 1 wherein the catalyst is an alkali metal salt of a monocarboxylic acid or dicarboxylic acid.
Claim 9
Dependent Claim
20 words
The process of claim 5 wherein the catalyst is an alkali metal salt of a monocarboxylic acid or dicarboxylic acid.
Claim 10
Dependent Claim
26 words
The process of claim 2 wherein the aprotic organic compound is selected from the group consisting of dimethylacetamide, dimethylformamide, N-methyl pyrrolidone, dimethyl sulfoxide, butyrolactone and caprolactam.
Claim 11
Dependent Claim
20 words
The process of claim 9 wherein the catalyst is an alkali metal salt of a monocarboxylic acid or dicarboxylic acid.
Claim 12
Dependent Claim
14 words
The process of claim 1 wherein Ar is selected from the group consisting of
Claim 13
Dependent Claim
9 words
A process for converting a bis-maleimide of the formula:
Claim 14
Dependent Claim
9 words
A process for converting a bis-maleimide of the formula:
Claim 15
Dependent Claim
14 words
The process of claim 12 wherein Ar is selected from the group consisting of
Claim 16
Dependent Claim
20 words
The process of claim 13 wherein the salt is sodium acetate or disodium maleate and the aprotic compound is dimethylacetamide.
Claim 17
Dependent Claim
26 words
The process of claim 1 wherein the bis-maleimide is dissolved in an organic solvent and polymerized to an ungelled fusible stage soluble in the same solvent.
Claim 18
Dependent Claim
17 words
A thermally stable polymer derived from the completely cyclized bis-maleimides according to the process of claim 1.
Claim 19
Dependent Claim
19 words
The polymers of claim 16 having a TGA inflection point, measured at 10*C. per minute of at least 400*C.
Claim 20
Dependent Claim
30 words
The process of claim 1 wherein the bis-maleimide is polymerized in the presence of 0.1 to 2.5 moles of a monomaleimide per mole of bis-maleimide, said maleimide having the formula
Claim 21
Dependent Claim
9 words
A copolymer according to the process of claim 18.
Claim 22
Dependent Claim
11 words
The copolymer of claim 19 in which the monomaleimide is N-phenylmaleimide.
Claim 23
Dependent Claim
7 words
A copolymer of 0.1 to 2.5 moles
Claim 24
Dependent Claim
7 words
A copolymer of 0.1 to 2.5 moles
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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |