US3728348A
Expired / Lapsed
US
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Dicarboxylic acids containing diketopiperazine groups and polymers prepared therefrom
Assignee: Honeywell International Inc
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Filing: 1970-05-21
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Granted: 1973-04-17
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Expires: 1990-05-21
Abstract
Abstract Dicarboxylic acids having the formula WHEREIN R1 represents a phenylene or alkylene radical and R2 represents a divalent organic radical, are prepared by reacting a tricarboxylic acid having the formula HOOCR1N(CH2COOH)2, such as nitrilotriacetic acid, with a diamine having the formula H2NR2NH2, such as hexamethylene diamine, in a substantially 2:1 molar ratio in the presence of an inert solvent. The dicarboxylic acids are useful as monomers in preparing linear film and fiberforming polyamides and polyesters in accordance with conventional methods for preparing such polymers from dicarboxylic acids.
Inventors
- 👤 M Litt
- 👤 L Lee
- 👤 E Pearce
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:59
CPC Classifications
C; C07; C07D; C07D241/00; C07D241/02; C07D241/06; C07D241/08; C08; C08G; C08G63/00; C08G63/68; C08G63/685; C08G63/6854; C08G63/6856; C08G69/00; C08G69/02; C08G69/26; C08G73/00; C08G73/06; C08G73/10; C08G73/14
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
10 words
A dicarboxylic acid of claim 1 wherein R1 is methylene.
Claim 2
Dependent Claim
39 words
A dicarboxylic acid of claim 1 wherein R2 has the formula -(CH2)n- wherein n is an integer from 1 to 10, or the formula -(CH2)pZ (CH2)p - wherein Z is a phenylene group is 0, 1, 2 or 3.
Claim 3
Dependent Claim
24 words
A dicarboxylic acid of claim 1 wherein R2 is phenylene or has the formula -(CH2)n- wherein n is an integer from 2 to 10.
Claim 4
Dependent Claim
10 words
A dicarboxylic acid of claim 4 wherein R1 is methylene.
Claim 5
Independent Claim
10 words
A method of preparing a dicarboxylic acid having the formula
Claim 6
Dependent Claim
9 words
A method of claim 6 wherein R1 is methylene.
Claim 7
Dependent Claim
35 words
A method of claim 6 wherein R2 has the formula -(CH2)n-wherein n is an integer from 1 to 10, or the formula -(CH2)pZ(CH2)p- wherein Z is phenylene and p is 0, 1, 2 or 3.
Claim 8
Dependent Claim
9 words
A method of claim 8 wherein R1 is methylene
Claim 9
Dependent Claim
23 words
A method of claim 19 wherein R2 is phenylene or has the formula -(CH2)n- wherein n is an integer from 2 to 10.
Claim 10
Dependent Claim
12 words
A method of claim 20 wherein the temperature is 80*C. to 180*C.
References Cited (Backward Citations)
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Cited
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US3485833A
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US3496148A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |