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US5021540A
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Polyimides from diaminobenzotrifluorides
Assignee: Occidental Chemical Corp
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Filing: 1990-09-18
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Granted: 1991-06-04
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Expires: 2010-09-18
Abstract
Abstract Polyimides are made by imidization of the product of reaction of dianhydrides with diaminobenzotrifluoride and bis(trifluoromethyl) oxydianilines. In preferred embodiments the polyimides are end capped with monoanhydride or monoamine residues.
Inventors
- 👤 Andrea Leone-Bay
- 👤 Steven L. Peake
- 👤 Stanley S. Kaminski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:58
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1003; C08G73/1007; C08G73/101; C08G73/1017; C08G73/1014; C08G73/1042
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
27 words
A polyimide resin made by reaction of a dianhydride, its diester or tetracid derivative having at least one aromatic ring in the molecule and a bis(trifluoromethyl) oxydianiline.
Claim 2
Dependent Claim
27 words
A polyimide resin made by reaction of a dianhydride, its diester or tetracid derivative having at least one aromatic ring in the molecule and a bis(trifluoromethyl) oxydianiline.
Claim 3
Dependent Claim
15 words
A polyimide resin defined by claim 1 wherein the bis(trifluoromethyl) oxydianiline is 4,4'(2,2' trifluoromethyl) oxydianiline.
Claim 4
Dependent Claim
35 words
A polyimide resin defined by claim 2 wherein the dianhydride is a member selected from the group consisting of pyromellitic dianhydride, 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'oxydiphthalic anhydride, 3,3',4,4'-diphenyl tetracarboxylic dianhydride, and 3,3',4,4'-sulfonyldiphthalic anhydride.
Claim 5
Dependent Claim
22 words
A polyimide resin defined by claim 1 wherein the diester is selected from the group of pyromellitic diester and 3,3',4,4'-benzophenone tetracarboxylic diester.
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) | 1994-06-03 | 1994-12-03 | 1995-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-03 | 1998-12-03 | 1999-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-03 | 2002-12-03 | 2003-06-04 | $7700.00 | Window Closed / Lapsed |