Patent US1784544A successfully refreshed from Google Patents.
Patent US4065345A successfully refreshed from Google Patents.
US4065345A
Expired / Lapsed
US
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Polyimide adhesives
Assignee: National Aeronautics and Space Administration
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Filing: 1976-10-22
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Granted: 1977-12-27
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Expires: 1996-10-22
Abstract
Abstract A process of preparing aromatic polyamide-acids for use as adhesives by reacting an aromatic dianhydride to an approximately equimolar amount of an aromatic diamine in a water or lower alkanol miscible ether solvent and wherein the polyamide-acids are converted to polyimides by heating to the temperature range of 200 DEG - 300 DEG C. and wherein the polyimides are thermally stable and insoluble in ethers and other organic solvents.
Inventors
- 👤 Donald J. Progar
- 👤 Vernon L. Bell
- 👤 Terry L. St. Clair
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:51
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067; C08G73/1003; C08G73/1007; C08G73/1028; C08G73/1032; C08G73/1046; C08G73/1053; C08G73/1057; C08G73/106
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
41 words
A method for preparing an adhesive solution comprising: reacting an aromatic dianhydride with an approximately equimolar quantity of an aromatic diamine, the reactants being previously dissolved in a liquid selected from the group consisting of 1,2-dimethoxyethane, bis(2-methoxyethyl)ether, 1,2,bis(2-methoxyethoxy)ethane and bis-[2-(2-methoxyethoxy) ethyl]ether.
Claim 2
Independent Claim
41 words
A method for preparing an adhesive solution comprising: reacting an aromatic dianhydride with an approximately equimolar quantity of an aromatic diamine, the reactants being previously dissolved in a liquid selected from the group consisting of 1,2-dimethoxyethane, bis(2-methoxyethyl)ether, 1,2,bis(2-methoxyethoxy)ethane and bis-[2-(2-methoxyethoxy) ethyl]ether.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein the diamine is selected from the grou pf diamines consisting of: 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,5-diaminobenzophenone, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, and 4,4'-diaminodiphenyl sulfone.
Claim 4
Dependent Claim
33 words
The method of claim 1 wherein the dianhydride is selected from the group of dianhydrides consisting of: 3,3'4,4'-benzophenone tetracarboxylic acid dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, bis(3,4-dicarboxyphenyl)sulfone dianhydride bis-4-(3',4'-dicarboxphenyoxy)sulfone dianhydride, bis(3,4-dicarboxphenyl)dimethysilane diandride, and 1,4-bis-(3',4'-dicarboxylphenyl dimethylsilyl)benzene dianhydride.
Claim 5
Dependent Claim
53 words
The method of claim 1 wherein the initial reactant product is an aromatic polyimide-acid having reccuring units of the formula: ##STR7## where Z is selected from the group consisting of ##STR8## R 2 being from alkyl and aryl groups; R 1 is ##STR9## and, Z' is selected from the group consisting of ##STR10##
Claim 6
Dependent Claim
75 words
Themethod of claim 4 including the further steps of applying the adhesive solution to substrate surfaces, allowing some or all of the solvent to evaporate, assembling together the treated substrate surfaces and heating the polyamide-acid in the temperature range of 200° C. to 300° C. for at least one hour to complete the evaporation of the solvent and to conver the polyamide-acid into a thermally resistant cyclic polyimidae having recurring units of the formula: ##STR11##
Claim 7
Dependent Claim
32 words
A high molecular weight polyimide adhesive resin bond prepared according to the method of claim 5, and having the inherent physical property characteristic of being insoluble in ethers and other organic solvents.
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) | 1980-12-26 | 1981-06-27 | 1981-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-26 | 1985-06-27 | 1985-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-26 | 1989-06-27 | 1989-12-27 | $7700.00 | Window Closed / Lapsed |