US4539392A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing polyimide prepolymer from ethylenically unsaturated dicarboxylic acid compound
Assignee: Toray Industries Inc
•
Filing: 1984-07-03
•
Granted: 1985-09-03
•
Expires: 2004-07-03
Abstract
Abstract Polyimide prepolymers having excellent heat resistance can be prepared in one stage by the reaction of polyamines and aromatic double bond-containing dicarboxylic acids or derivatives thereof in the presence of oxide compounds of phosphorus without isolating any intermediate in the course of said reaction.
Inventors
- 👤 Sho Kadoi
- 👤 Toshihiko Aya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:40
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/12; C08G73/121
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
99 words
A method for preparing a polyimide prepolymer, which comprises effecting reaction between a polyamine which has the following general formula (I), R(NH.sub.2).sub.n (I) in which R is an organic group having not less than 2 carbon atoms ad n is an integer of 2 or above, and a compound selected from the group consisting of dicarboxylic acids having at least one aliphatic double bond and derivatives thereof in the ratio of 0.52-0.95 mole of the latter per mole of amino group contained in the polyamine used, in contact with an effective ring closing amount of an oxide of phosphorus.
Claim 2
Independent Claim
99 words
A method for preparing a polyimide prepolymer, which comprises effecting reaction between a polyamine which has the following general formula (I), R(NH.sub.2).sub.n (I) in which R is an organic group having not less than 2 carbon atoms ad n is an integer of 2 or above, and a compound selected from the group consisting of dicarboxylic acids having at least one aliphatic double bond and derivatives thereof in the ratio of 0.52-0.95 mole of the latter per mole of amino group contained in the polyamine used, in contact with an effective ring closing amount of an oxide of phosphorus.
Claim 3
Dependent Claim
24 words
The method according to claim 1 wherein said oxide compound of phosphorus is selected from the group consisting of phosphorus pentaoxide and polyphosphoric acid.
Claim 4
Dependent Claim
82 words
The method according to claim 1 wherein said R in formula (I) is a radical selected from the group consisting of a benzene ring or radicals consisting of not less than 2 benzene rings linked to each other by a direct bond or a bonding group selected from the group consisting of --O--, --S--, --CO--, --SO 2 -- and ##STR3## wherein R' is a radical selected from the group consisting of hydrogen, an aliphatic group, an aromatic group and an alicyclic group.
Claim 5
Dependent Claim
11 words
The method according to claim 1 wherein said polyamine is 4,4'-diaminodiphenylmethane.
Claim 6
Dependent Claim
34 words
The method according to claim 1 wherein said compound selected from the group consisting of dicarboxylic acids having aliphatic double bonds and the derivatives thereof is a dicarboxylic anhydride having an aliphatic double bond.
Claim 7
Dependent Claim
18 words
The method according to claim 5 wherein said dicarboxylic anhydride having an aliphatic double bond is maleic anhydride.
Claim 8
Dependent Claim
41 words
The method according to claim 1 wherein the oxide compound of phosphorus is used in an amount of 0.4--3 dehydrating equivalent per mole of compound selected from the group consisting of dicarboxylic acids having aliphatic double bonds and the derivatives thereof.
Claim 9
Dependent Claim
42 words
The method according to claim 1 wherein the compound selected from the group consisting of dicarboxylic acids having aliphatic double bonds and the derivatives thereof is used in an amount of 0.6-0.8 mole per mole of amino group contained in said polyamine.
Claim 10
Dependent Claim
16 words
The method according to claim 1 wherein the reaction is effected in the absence of solvent.
Claim 11
Dependent Claim
16 words
The method according to claim 1 wherein the reaction is effected in an aprotic polar solvent.
Claim 12
Dependent Claim
25 words
The method according to claim 10 wherein the reaction is started after the oxide compound of phosphorus is previously dissolved in an aprotic polar solvent.
Claim 13
Dependent Claim
22 words
The method according to claim 10 wherein said aprotic polar solvent is selected from the group consisting of dimethylformamide, N-methylpyrrolidone and dimethylacetamide.
Claim 14
Dependent Claim
33 words
The method according to claim 1 wherein the reaction is started in an organic medium capable of dissolving the reactants but not of dissolving more than 50 weight % of the resulting product.
Claim 15
Dependent Claim
14 words
The method according to claim 13 wherein said organic medium is a halogenated hydrocarbon.
Claim 16
Dependent Claim
18 words
The method according to claim 1 wherein the reaction is effected at a temperature of 70-200 ° C.
References Cited (Backward Citations)
US3732189A
Cited
US4465823A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |