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US4634760A
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Novel copolyimides and polyamic acid precursors therefor
Assignee: General Electric Co
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Filing: 1985-11-14
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Granted: 1987-01-06
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Expires: 2005-11-14
Abstract
Abstract Copolyimides having good solvent resistance, thermal stability and processability contain about 2-50 mole percent of structural units derived from a tetracarboxybiphenyl, in combination with other structural units typically derived from bisphenol A dianhydride.
Inventors
- 👤 Tohru Takekoshi
- 👤 Donald C. Clagett
- 👤 Stephen M. Cooper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:02
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067; C08G73/1042; C08G73/1057; C08G73/1064; C08G73/1071
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
122 words
A polymer comprising structural units having the formulas ##STR4## wherein: X 1 is OH and Y is NH, or X 1 and Y taken together are N; R 1 is an aromatic hydrocarbon radical containing about 6-20 carbon atoms, or a halogenated derivative thereof, an alkylene or cycloalkylene radical containing about 2-20 carbon atoms, or a bis-alkylene poly(dialkylsiloxane) radical; Z 1 is --R 2 --, --O--, --CO--, --S x --, --SO 2 --, --O--Q--O--, --S--Q--S-- or --SO 2 --Q--SO 2 --; R 2 is a divalent aliphatic or alicyclic radical containing about 1-12 carbon atoms; Q is a divalent aliphatic or aromatic radical; and x is 1 or 2; said polymer containing about 2-50 mole percent of structural units having formula I.
Claim 2
Dependent Claim
122 words
A polymer comprising structural units having the formulas ##STR4## wherein: X 1 is OH and Y is NH, or X 1 and Y taken together are N; R 1 is an aromatic hydrocarbon radical containing about 6-20 carbon atoms, or a halogenated derivative thereof, an alkylene or cycloalkylene radical containing about 2-20 carbon atoms, or a bis-alkylene poly(dialkylsiloxane) radical; Z 1 is --R 2 --, --O--, --CO--, --S x --, --SO 2 --, --O--Q--O--, --S--Q--S-- or --SO 2 --Q--SO 2 --; R 2 is a divalent aliphatic or alicyclic radical containing about 1-12 carbon atoms; Q is a divalent aliphatic or aromatic radical; and x is 1 or 2; said polymer containing about 2-50 mole percent of structural units having formula I.
Claim 3
Dependent Claim
19 words
A polymer according to claim 1 which is a copolyimide wherein X 1 and Y taken together are N.
Claim 4
Dependent Claim
16 words
A polymer according to claim 2 wherein the units of formula I are derived from 3,3',4,4'-tetracarboxybiphenyl.
Claim 5
Dependent Claim
13 words
A polymer according to claim 3 wherein Z 1 is --R 2 --.
Claim 6
Dependent Claim
11 words
A polymer according to claim 4 wherein R 2 is --O--Q--O--.
Claim 7
Dependent Claim
36 words
A polymer according to claim 5 wherein Q has the formula ##STR5## wherein R 4 is a straight chain or branched alkylene radical containing 1-5 carbon atoms and each X 2 is independently hydrogen or halogen.
Claim 8
Dependent Claim
14 words
A polymer according to claim 6 wherein R 1 is an aromatic hydrocarbon radical.
Claim 9
Dependent Claim
18 words
A polymer according to claim 7 wherein the units of formula I comprise about 5-25 mole percent thereof.
Claim 10
Dependent Claim
17 words
A polymer according to claim 8 wherein R 4 is isopropylidene and each X 2 is hydrogen.
Claim 11
Dependent Claim
18 words
A polymer according to claim 9 wherein the units of formula II are derived from the bis(3,4-dicarboxyphenoxy) compound.
Claim 12
Dependent Claim
15 words
A polymer according to claim 10 wherein R 1 is the m-phenylene or bis(4-phenylene)methane radical.
Claim 13
Dependent Claim
11 words
A polymer according to claim 11 wherein R 1 is m-phenylene.
Claim 14
Dependent Claim
11 words
A polymer according to claim 11 wherein R 1 is bis(4-phenylene)methane.
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) | 1990-01-05 | 1990-07-07 | 1991-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-05 | 1994-07-07 | 1995-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-05 | 1998-07-07 | 1999-01-06 | $7700.00 | Window Closed / Lapsed |