US5428102A
Expired / Lapsed
US
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Low dielectric polyimides
Assignee: National Aeronautics and Space Administration
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Filing: 1994-05-02
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Granted: 1995-06-27
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Expires: 2014-05-02
Abstract
Abstract A series of polyimides based on the dianhydride of 1,4-bis(3,4-dicarboxyphenoxy)benzene (HQDEA) or on 2,2-bis[4(3-aminophenoxy)phenyl]hexafluoropropane (3-BDAF) are evolved from high molecular weight polyamic acid solutions yielding flexible free-standing films and coatings in the fully imidized form which have a dielectric constant in the range of 2.5 to 3.1 at 10 GHz.
Inventors
- 👤 Anne K. St. Clair
- 👤 Terry L. St. Clair
- 👤 William P. Winfree
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:00
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1003; C08G73/1007
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
35 words
A low dielectric polymer composition comprising a linear aromatic polyimide formed as the reaction product of 2,2-bis[4(3-aminophenoxy)phenyl]hexafluoropropane and 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, the linear aromatic polyimide having the following general structural formula: ##STR6## where n is 10-100.
Claim 2
Dependent Claim
35 words
A low dielectric polymer composition comprising a linear aromatic polyimide formed as the reaction product of 2,2-bis[4(3-aminophenoxy)phenyl]hexafluoropropane and 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, the linear aromatic polyimide having the following general structural formula: ##STR6## where n is 10-100.
Claim 3
Dependent Claim
44 words
A low dielectric polymer composition having the following general structural formula: ##STR7## where n is 10-100, the low dielectric polymer composition comprising a linear aromatic polyimide formed as the reaction product of 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride and an aromatic diamine selected from the group consisting of:
Claim 4
Dependent Claim
44 words
A low dielectric polymer composition having the following general structural formula: ##STR7## where n is 10-100, the low dielectric polymer composition comprising a linear aromatic polyimide formed as the reaction product of 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride and an aromatic diamine selected from the group consisting of:
Claim 5
Dependent Claim
6 words
2-bis[4(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-oxydianiline, 3,3'-oxydianiline, 1,3-bis(aminophenoxy)benzene, and 3,3'-diaminobenzophenone.
Claim 6
Dependent Claim
6 words
2-bis[4(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-oxydianiline, 3,3'-oxydianiline, 1,3-bis(aminophenoxy)benzene, and 3,3'-diaminobenzophenone.
Claim 7
Dependent Claim
43 words
A low dielectric polymer composition having the following general structural formula: ##STR8## where n is 10-100, the low dielectric polymer composition comprising a linear aromatic polyimide formed as the reaction product of 2,2-bis[4(3-aminophenoxy)phenyl]hexafluoropropane with an aromatic dianhydride selected from the group consisting of:
Claim 8
Dependent Claim
43 words
A low dielectric polymer composition having the following general structural formula: ##STR8## where n is 10-100, the low dielectric polymer composition comprising a linear aromatic polyimide formed as the reaction product of 2,2-bis[4(3-aminophenoxy)phenyl]hexafluoropropane with an aromatic dianhydride selected from the group consisting of:
Claim 9
Dependent Claim
16 words
2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 4,4'-oxydiphthalic anhydride, pyromellitic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 3,3'-4,4'-benzophenone tetracarboxylic dianhydride, and isopropylidene diphthalic anhydride.
Claim 10
Dependent Claim
16 words
2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 4,4'-oxydiphthalic anhydride, pyromellitic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 3,3'-4,4'-benzophenone tetracarboxylic dianhydride, and isopropylidene diphthalic anhydride.
Claim 11
Dependent Claim
10 words
A film prepared from a polyimide according to claim 2.
Claim 12
Dependent Claim
10 words
A coating prepared from a polyimide according to claim 2.
Claim 13
Dependent Claim
10 words
A film prepared from a polyimide according to claim 3.
Claim 14
Dependent Claim
10 words
A coating prepared from a polyimide according to claim 3.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1998-06-26 | 1998-12-26 | 1999-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-06-26 | 2002-12-26 | 2003-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-06-26 | 2006-12-26 | 2007-06-27 | $7700.00 | Window Closed / Lapsed |