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US4311615A
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Electrically conductive palladium containing polyimide films
Assignee: National Aeronautics and Space Administration
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Filing: 1980-03-28
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Granted: 1982-01-19
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Expires: 2000-03-28
Abstract
Abstract This invention relates to improved lightweight, high temperature resistent, electrically conductive, palladium containing, polyimide films and methods of preparing same for use in aerodynamic and space application. A palladium (II) ion-containing polyamic acid solution is prepared by reacting an aromatic dianhydride with an equimolar quantity of a palladium II ion-containing salt or complex and the reactant product is cast as a thin film onto a surface and cured at approximately 300 DEG C. to produce a flexible electrically conductive cyclic palladium containing polyimide. The source of palladium ions is selected from the group of palladium II compounds consisting of LiPdCl4, Pd[S(CH3)2]2Cl2,Na2PdCl4, and PdCl2.
Inventors
- 👤 with respect to an invention of Frosch Robert A. Administrator of the National Aeronautics and Space Administration
- 👤 Larry T. Taylor
- 👤 Anne K. St. Clair
- 👤 Vicki C. Carver
- 👤 Thomas A. Furtsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:14
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/06; H01B1/12; C; C08; C08L; C08L79/00; C08L79/04; C08L79/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
98 words
A method for preparing a palladium (II) ion-containing polyamic acid solution which comprises: reacting an aromatic dianhydride with an equimolar quantity of an aromatic diamine followed by the addition of a palladium (II) ion-containing salt or complex selected from the group consisting of Li 2 PdCl 4 , Pd[S(CH 3 ) 2 ] 2 Cl 2 and PdCl 2 ; the dianhydride and diamine reactants being previously dissolved in a solvent or mixture of solvents at least one of which is selected from the group consisting of, N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl-2-pyrrolidone, dimethylsulfone, tetrahydrofuran, m- or p-dioxane, bis(2-methoxyethyl)ether, and 1,2-bis(2-methoxyethoxy)ethane.
Claim 2
Independent Claim
98 words
A method for preparing a palladium (II) ion-containing polyamic acid solution which comprises: reacting an aromatic dianhydride with an equimolar quantity of an aromatic diamine followed by the addition of a palladium (II) ion-containing salt or complex selected from the group consisting of Li 2 PdCl 4 , Pd[S(CH 3 ) 2 ] 2 Cl 2 and PdCl 2 ; the dianhydride and diamine reactants being previously dissolved in a solvent or mixture of solvents at least one of which is selected from the group consisting of, N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl-2-pyrrolidone, dimethylsulfone, tetrahydrofuran, m- or p-dioxane, bis(2-methoxyethyl)ether, and 1,2-bis(2-methoxyethoxy)ethane.
Claim 3
Dependent Claim
38 words
The method of claim 1 wherein the diamine is selected from the group of aromatic diamines consisting of: 3,3'-, 3,4'-, or 4,4'-oxydianiline; 3,3'-, 3,4-, or 4,4'-diaminobenzophenone; 3,3'-, 3,4'-, or 4,4'-diaminodiphenylmethane; meta- or para-phenylenediamine; and 3,3'-, 3,4'-, or 4,4'-diaminodiphenylsulfone.
Claim 4
Dependent Claim
37 words
A method of claim 1 wherein the dianhydride is selected from the group of aromatic 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'-dicarboxyphenoxy)diphenyl sulfone dianhydride, 2,2-bis(3,4-carboxyphenyl)hexafluoropropane dianhydride, pyromellitic dianhydride, and 4,4'-bis-(3,4-dicarboxyphenoxy)diphenylsulfide dianhydride.
Claim 5
Dependent Claim
61 words
The method of claim 1 wherein the diamine-dianhydride-palladium salt reactant product is a palladium ion-containing aromatic polyamic acid which has recurring units of the formula: ##STR2## where R 1 is selected from the group consisting of ##STR3## where Z is selected from ##STR4## and, where R 2 is selected from the group consisting of ##STR5## where Z' is selected from ##STR6##
Claim 6
Dependent Claim
21 words
The method of claim 1 wherein the source of palladium (II) ions is lithium tetrachloropalladate (II) (Li 2 PdCl 4 ).
Claim 7
Dependent Claim
24 words
The method of claim 1 wherein the source of palladium (II) ions is bis(dimethylsulfide)dichloropalladium (II) (Pd[S(CH 3 ) 2 ] 2 Cl 2 ).
Claim 8
Dependent Claim
18 words
The method of claim 1 wherein the source of palladium (II) ions is palladium chloride (PdCl 2 ).
Claim 9
Dependent Claim
95 words
The method of claim 1 including the further step of recovering an electrically conductive palladium containing polyimide film by casting a thin film of the palladium ion-containing polyamic acid solution onto a surface, and heating the film in air at 300° C. to produce a flexible, electrically conductive, cyclic palladium containing polyimide having the recurring units of the formula: ##STR7## where R 1 is selected from the group consisting of ##STR8## where Z is selected from ##STR9## and, where R 2 is selected from the group consisting of ##STR10## where Z' is selected from ##STR11##
Claim 10
Dependent Claim
35 words
The method of claim 8 wherein the volume resistivity of the recovered polyimide film is on the order of 6.1×10 10 ohm-cm and the film surface resistivity in on the order of 4.5×10 -7 ohm-cm.
Claim 11
Dependent Claim
20 words
The method of claim 9 wherein the palladium ion source for the conductive film is Li 2 PdCl 4 .
Claim 12
Dependent Claim
44 words
The method of claim 8 wherein the volume resistivity of the recovered polyimide film is on the order of 3.3×10 10 ohm-cm and the film surface resistivity is of such a low value as to prevent measurement by the standard ASTM method of testing.
Claim 13
Dependent Claim
24 words
The method of claim 11 wherein the palladium ion source for the conductive film is Pd[S(CH 3 ) 2 ] 2 Cl 2 .
References Cited (Backward Citations)
US3073784A
Cited
US3718488A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-01-18 | 1985-07-20 | 1986-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-18 | 1989-07-20 | 1990-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-18 | 1993-07-20 | 1994-01-19 | $7700.00 | Window Closed / Lapsed |