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US4303779A Expired / Lapsed US ⏱️ 0.0 years remaining

Thermosetting imide resins from dihydrazide

Assignee: Evonik Operations GmbH
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Filing: 1979-11-27
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Granted: 1981-12-01
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Expires: 1999-11-27
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Abstract

Abstract Novel imide resins are prepared by reacting a mixture of a bisimide of an unsaturated dicarboxylic acid and a monoimide with a dihydrazide of a dicarboxylic acid, preferably in an organic solvent or diluent at elevated temperature for a period of time insufficient to yield an insoluble, infusible, fully cured imide resin. Solutions of the resulting prepolymerization product are stable at room temperature and their viscosity remains substantially unchanged for a prolonged period of time. Fully cured imide resins and articles thereof of a high heat resistance are obtained by heating said prepolymerized imide resin or materials such as fibers, metal wire webs, and others impregnated therewith, if desired, in the presence of curing catalysts, inhibitors, fillers and other materials to curing temperature up to 350° C.

Inventors

  • 👤 Horst Stenzenberger

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 00:16
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/12; C08G73/121; C08G73/122; C08G73/08; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31721

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 126 words
A thermosetting imide resin comprising the reaction product of (a) a mixture of an N,N'-bisimide of an unsaturated dicarboxylic acid of the general formula of ##STR10## and a monoimide of the general formula (II) ##STR11## wherein the residue A signifies a divalent organic group with at least two carbon atoms, E is selected from the group consisting of alkyl, cycloalkyl, and aryl groups and B a divalent organic group of the formulas indicated hereinbelow ##STR12## with (b) the dihydrazide of an organic dicarboxylic acid of the general formula (III) ##STR13## wherein D represents a divalent organic group, the molar proportion of the reaction between the unsaturated imide groups contained in the mixture and the hydrazide groups contained in the mixture ##EQU2## being between 1.1 and 100.
Claim 2
Dependent Claim 126 words
A thermosetting imide resin comprising the reaction product of (a) a mixture of an N,N'-bisimide of an unsaturated dicarboxylic acid of the general formula of ##STR10## and a monoimide of the general formula (II) ##STR11## wherein the residue A signifies a divalent organic group with at least two carbon atoms, E is selected from the group consisting of alkyl, cycloalkyl, and aryl groups and B a divalent organic group of the formulas indicated hereinbelow ##STR12## with (b) the dihydrazide of an organic dicarboxylic acid of the general formula (III) ##STR13## wherein D represents a divalent organic group, the molar proportion of the reaction between the unsaturated imide groups contained in the mixture and the hydrazide groups contained in the mixture ##EQU2## being between 1.1 and 100.
Claim 3
Dependent Claim 63 words
The imide resin of claim 1 wherein the bisimide is a bisimide selected from the group consisting of 1,2-bismaleimido ethane, 1,4-bismaleimido butane, 1,6-bismaleimido hexane, 1,12-bismaleimido dodecane, 1,6-bismaleimido-(2,2,4-trimethyl)hexane, 1,3-bismaleimido benzene, 1,4-bismaleimido benzene, 4,4'-bismaleimido diphenyl methane, 4,4'-bismaleimido diphenyl ether, 4,4'-bismaleimido diphenyl sulfide, 4,4'-bismaleimido diphenyl sulfone, 4,4'-bismaleimido dicyclohexyl methane, 2,4-bismaleimido toluene, 2,6-bismaleimido toluene, N,N'-m-xylylene bismaleimide, N,N'-p-xylylene bismaleimide, N,N'-m-phenylene biscitraconic acid imide, N,N'-4,4'-diphenylmethane citraconimide, and N,N-4,4'-diphenylmethane bisitaconimide.
Claim 4
Dependent Claim 35 words
The imide resin of claim 1 wherein the monoimide is a monoimide selected from the group consisting of N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-dodecylmaleimide, N-isobutylmaleimide, N-isopropylmaleimide, N-phenylmaleimide, N-phenylcitroconimide, N-phenylitaconimide, N-toluylmaleimide, N-mono-chlorophenylmaleimide, N-biphenylmaleimide, N-naphthylmaleimide, N-vinylmaleimide, N-allylmaleimide, and N-cyclohexylmaleimide.
Claim 5
Dependent Claim 67 words
The imide resin of claim 1 wherein the dicarboxylic acid dihydrazide is a dihydrazide selected from the group consisting of: oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, pimelic acid dihydrazide, suberic acid dihydrazide, sebacic acid dihydrazide, cyclohexane dicarboxylic acid dehydrazide, terephthalic acid dihydrazide, isophthalic acid dihydrazide, 2,6-naphthalene dicarboxylic acid dihydrazide, 2,7-naphthalene dicarboxylic acid dihydrazide and mixtures of said dihydrazides.
Claim 6
Dependent Claim 20 words
The imide resin of claim 1, said resin being prepared by using a mixture of bisimides as the bisimide reactant.
Claim 7
Dependent Claim 20 words
The imide resin of claim 1, said resin being prepared by using a mixture of monoimides as the monoimide reactant.
Claim 8
Dependent Claim 22 words
The imide resin of claim 1, said resin being prepared by using a mixture of dicarboxylic acid dihydrazide as the dihydrazide reactant.
Claim 9
Dependent Claim 19 words
The imide resin of claim 1, said resin being prepared by reacting 4,4'-bismaleimido diphenylmethane, maleimidobenzene and isophthalic acid dihydrazide.
Claim 10
Dependent Claim 13 words
The imide resin of claim 1 containing an organic peroxide as curing catalyst.
Claim 11
Dependent Claim 10 words
The imide resin of claim 1 containing a curing inhibitor.
Claim 12
Dependent Claim 175 words
In a process of producing a thermosetting imide resin, the step which comprises heating (a) a mixture of an N,N'-bisimide of an unsaturated dicarboxylic acid of the general formula of ##STR14## and a monoimide of the general formula (II) ##STR15## wherein the residue A signifies a divalent organic group with at least two carbon atoms, E is selected from the group consisting of alkyl, cycloalkyl, and aryl groups and B a divalent organic group of the formulas indicated hereinbelow ##STR16## with (b) the dihydrazide of an organic dicarboxylic acid of the general formula (III) ##STR17## wherein D represents a divalent organic group, the molar proportion of the reaction between the unsaturated imide groups contained in the mixture and the hydrazide groups contained in the mixture ##EQU3## being between 1.1 and 100 in a molar proportion of imide groups to dihydrazide group between about 1.1 and about 100 in an organic diluent to a temperature not substantially exceeding about 180° C. for a period of time to yield a moldable and curable, thermosetting prepolymerized imide resin.
Claim 13
Dependent Claim 175 words
In a process of producing a thermosetting imide resin, the step which comprises heating (a) a mixture of an N,N'-bisimide of an unsaturated dicarboxylic acid of the general formula of ##STR14## and a monoimide of the general formula (II) ##STR15## wherein the residue A signifies a divalent organic group with at least two carbon atoms, E is selected from the group consisting of alkyl, cycloalkyl, and aryl groups and B a divalent organic group of the formulas indicated hereinbelow ##STR16## with (b) the dihydrazide of an organic dicarboxylic acid of the general formula (III) ##STR17## wherein D represents a divalent organic group, the molar proportion of the reaction between the unsaturated imide groups contained in the mixture and the hydrazide groups contained in the mixture ##EQU3## being between 1.1 and 100 in a molar proportion of imide groups to dihydrazide group between about 1.1 and about 100 in an organic diluent to a temperature not substantially exceeding about 180° C. for a period of time to yield a moldable and curable, thermosetting prepolymerized imide resin.
Claim 14
Dependent Claim 15 words
The process of claim 11, in which the diluent is an inert, polar organic solvent.
Claim 15
Dependent Claim 27 words
The process of claim 12, in which the inert, polar organic solvent is a solvent selected from the group consisting of dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and tetramethyl urea.
Claim 16
Dependent Claim 47 words
The process of claim 11, comprising the additional step of hardening and curing the prepolymerized imide resin by further heating the same to a temperature between about 100° C. and about 350° C. to yield a substantially insoluble, infusible, cross-linked polymerized imide resin of high thermal stability.
Claim 17
Dependent Claim 21 words
The process of claim 14, in which the additional step is carried out with the addition of a curing accelerating catalyst.
Claim 18
Dependent Claim 26 words
The process of claim 11, in which the step of producing the prepolymerized imide resin is carried out with the addition of a curing inhibiting agent.
Claim 19
Dependent Claim 39 words
The solution of moldable and curable, thermosetting, prepolymerized imide resin of claim 1 in an inert, polar, organic solvent, said solution being stable on storage for a prolonged period of time without its viscosity substantially increasing during said storage.

References Cited (Backward Citations)

US3562223A Cited
US4211860A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-11-30 1985-06-01 1985-12-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-11-30 1989-06-01 1989-12-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-11-30 1993-06-01 1993-12-01 $7700.00 Window Closed / Lapsed

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