Patent US4389510A successfully refreshed from Google Patents.
US4389510A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water soluble polyimide prepared from 1,2,3,4 butane tetracarboxylic acid and method of preparation
Assignee: RTX Corp
•
Filing: 1981-04-17
•
Granted: 1983-06-21
•
Expires: 2001-04-17
Abstract
Abstract A water soluble polyimide is described comprising the reaction product of butane tetracarboxylic acid (BTC), a multifunctional amine of the formula: <IMAGE> and a diamine, where the multifunctional amine constitutes at least 5% of the total amine equivalents of the reactants and preferably 15% to 40%. An aqueous solution of this polyimide, a method of coating electrical conductors with this polyimide, and the electrical conductors insulated with the polyimide are also described. The polyimide, particularly useful as an insulation coating for magnet wire, is made by reacting the multifunctional amine with the BTC followed by reaction with the diamine, removing the condensed water produced during the reaction.
Inventors
- 👤 Charles W. McGregor
- 👤 Lionel J. Payette
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:39
CPC Classifications
C; C08; C08L; C08L79/00; C08L79/04; C08L79/08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1003; C08G73/1007; C08G73/1028; C08G73/1042; H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/308
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
58 words
A water soluble polyimide comprising the reaction product of 1, 2, 3, 4 butane tetracarboxylic acid, a multifunctional amine of the formula: ##STR5## and at least one diamine; where n=0.3, the multifunctional amine constitutes at least 5% of the total amine equivalents of the reactants and the butane tetracarboxylic acid to amine molar ratio is 100:94.8 to 100:98.
Claim 2
Dependent Claim
58 words
A water soluble polyimide comprising the reaction product of 1, 2, 3, 4 butane tetracarboxylic acid, a multifunctional amine of the formula: ##STR5## and at least one diamine; where n=0.3, the multifunctional amine constitutes at least 5% of the total amine equivalents of the reactants and the butane tetracarboxylic acid to amine molar ratio is 100:94.8 to 100:98.
Claim 3
Dependent Claim
19 words
The water soluble polyimide of claim 1 wherein the diamine comprises a mixture of methylene dianiline and hexamethylene diamine.
Claim 4
Dependent Claim
23 words
The water soluble polyimide of claim 1 wherein the multifunctional amine constitutes at least 40% of the total amine equivalents of the reactants.
Claim 5
Independent Claim
92 words
A method of making a water soluble polyimide comprising (a) at least partially reacting 1, 2, 3, 4 butane tetracarboxylic acid with a multifunctional amine of the formula: ##STR6## (b) adding an aromatic diamine to the reaction mixture and heating to effect further reaction, (c) adding an aliphatic diamine to the reaction mixture, the butane tetracarboxylic acid to amine molar ratio being about 100:94.8 to 100:98, and (d) driving off all reaction condensed water and heating to effect further reaction, thereby forming a water soluble polyimide with a nondispersed molecular weight distribution.
Claim 6
Independent Claim
92 words
A method of making a water soluble polyimide comprising (a) at least partially reacting 1, 2, 3, 4 butane tetracarboxylic acid with a multifunctional amine of the formula: ##STR6## (b) adding an aromatic diamine to the reaction mixture and heating to effect further reaction, (c) adding an aliphatic diamine to the reaction mixture, the butane tetracarboxylic acid to amine molar ratio being about 100:94.8 to 100:98, and (d) driving off all reaction condensed water and heating to effect further reaction, thereby forming a water soluble polyimide with a nondispersed molecular weight distribution.
Claim 7
Dependent Claim
26 words
The method of claim 4 further comprising (d) adding an aqueous solution of ammonia to the reaction mixture to make an aqueous solution of the polyimide.
Claim 8
Dependent Claim
20 words
The method of claim 4 or 5 where the aromatic diamine is methylene dianiline and the aliphatic diamine is hexamethylene-diamine.
Claim 9
Dependent Claim
63 words
The process of claim 4 or 5 where in step (a) the reaction takes place at 50° C. to 100° C. for up to one hour, in step (b) the reaction takes place at 50° C. to 105° C. for up to one hour and in step (c) the reaction takes place at 100° C. to 200° C. for up to 12 hours.
References Cited (Backward Citations)
US3673145A
Cited
US3840495A
Cited
DE2434176A1
Cited
US3925313A
Cited
JPS5077141A
Cited
DE2519673A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-06-20 | 1986-12-20 | 1987-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-20 | 1990-12-20 | 1991-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-20 | 1994-12-20 | 1995-06-21 | $7700.00 | Window Closed / Lapsed |