US4569988A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyimides of 4,4'-(hexafluoroisopropylidene)bis(o-phthalic anhydride) and aliphatic diamines
Assignee: RTX Corp
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Filing: 1984-12-24
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Granted: 1986-02-11
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Expires: 2004-12-24
Abstract
Abstract A low temperature processable, thermoplastic polyimide and methods for making and using the same. The polyimide has repeating polymer units of the formula ##STR1## wherein n is 2 to about 20 and the molecular weight of the polymer chain is about 5,000 to about 50,000. The polymer is made by reacting 4,4'-(hexafluoroisopropylidene)bis(o-phthalic anhydride) with a diamine having the formula H 2 N(CH 2 ) n NH 2 wherein n is 2 to about 20 to form a polyamic acid. The polyamic acid is imidized to form the polyimide described above. The polyimide is particularly adapted to use as a hot melt adhesive by placing it between two articles and applying heat and pressure.
Inventors
- 👤 Daniel A. Scola
- 👤 Ruth H. Pater
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:18
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1039
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
42 words
A thermoplastic polyimide consisting essentially of repeating polymer units of the formula ##STR7## wherein n is 2 to about 20 and the molecular weight of the polymer chain is about 5,000 to about 50,000, said polymer exhibiting the property low temperature processability.
Claim 2
Dependent Claim
42 words
A thermoplastic polyimide consisting essentially of repeating polymer units of the formula ##STR7## wherein n is 2 to about 20 and the molecular weight of the polymer chain is about 5,000 to about 50,000, said polymer exhibiting the property low temperature processability.
Claim 3
Dependent Claim
15 words
The polyimide as recited in claim 1 wherein n is about 10 to about 14.
Claim 4
Dependent Claim
11 words
A polyimide as recited in claim 1 wherein n is 12.
Claim 5
Dependent Claim
61 words
A method of making the polyimide recited in claim 1 comprising reacting an anhydride with a diamine to form a polyamic acid and imidizing the polyamic acid to form a polyimide wherein the anhydride is 4,4'-(hexafluoroisopropylidene)bis(o-phthalic anhydride) and the diamine is a compound having the formula H 2 N(CH 2 ) n NH 2 where n is 2 to about 20.
Claim 6
Dependent Claim
28 words
The method as recited in claim 4 wherein the anhydride is mixed with the diamine by adding the anhydride to the diamine over about 25 to 30 minutes.
References Cited (Backward Citations)
US3310573A
Cited
GB1062435A
Cited
US3356648A
Cited
GB1216505A
Cited
US4063984A
Cited
US4336175A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-02-10 | 1989-08-12 | 1990-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-10 | 1993-08-12 | 1994-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-10 | 1997-08-12 | 1998-02-11 | $7700.00 | Window Closed / Lapsed |