Patent US4297474A successfully refreshed from Google Patents.
US4297474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyetherimides prepared by self-condensation of hydroxyaryl phthalimide salts
Assignee: General Electric Co
•
Filing: 1980-02-29
•
Granted: 1981-10-27
•
Expires: 2000-02-29
Abstract
Abstract Polyetherimides are provided which are based on the self-condensation in a dipolar aprotic solvent of a hydroxyaryl phthalimide salt having a nuclear bound leaving radical on the phthalimide ring. The polyetherimides are injection-moldable high performance thermoplastics.
Inventors
- 👤 Frank J. Williams, III
- 👤 Howard M. Relles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:20
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/12; C08G73/125; C08G73/124
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
35 words
Polyetherimides comprising chemically combined units of the formula, ##STR11## where R is a trivalent C.sub.(6-13) aromatic organic radical, R 1 is a divalent C.sub.(6-30) aromatic organic radical and X is selected from --O--, or --S--.
Claim 2
Dependent Claim
35 words
Polyetherimides comprising chemically combined units of the formula, ##STR11## where R is a trivalent C.sub.(6-13) aromatic organic radical, R 1 is a divalent C.sub.(6-30) aromatic organic radical and X is selected from --O--, or --S--.
Claim 3
Dependent Claim
11 words
A polyetherimide in accordance with claim 1, where R is ##STR12##
Claim 4
Dependent Claim
11 words
A polyetherimide in accordance with claim 1, where R is ##STR13##
Claim 5
Dependent Claim
12 words
A polyetherimide in accordance with claim 1, where R 1 is ##STR14##
Claim 6
Dependent Claim
12 words
A polyetherimide in accordance with claim 1, where R 1 is ##STR15##
Claim 7
Dependent Claim
12 words
A polyetherimide in accordance with claim 1, where R 1 is ##STR16##
Claim 8
Independent Claim
83 words
A method for making polyetherimide which comprises (1) heating a mixture comprising a phthalimide salt of the formula, ##STR17## in a dipolar aprotic solvent, (2) allowing the mixture of (1) to cool to ambient temperatures and (3) effecting the precipitation of polyetherimide from the mixture of (2), where R is a trivalent C.sub.(6-30) aromatic organic radical, R 1 is a divalent C.sub.(6-30) aromatic organic radical, X is selected from --O--, or --S--, and M is an alkali metal ion or an ammonium salt.
Claim 9
Independent Claim
83 words
A method for making polyetherimide which comprises (1) heating a mixture comprising a phthalimide salt of the formula, ##STR17## in a dipolar aprotic solvent, (2) allowing the mixture of (1) to cool to ambient temperatures and (3) effecting the precipitation of polyetherimide from the mixture of (2), where R is a trivalent C.sub.(6-30) aromatic organic radical, R 1 is a divalent C.sub.(6-30) aromatic organic radical, X is selected from --O--, or --S--, and M is an alkali metal ion or an ammonium salt.
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) | 1984-10-26 | 1985-04-27 | 1985-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-26 | 1989-04-27 | 1989-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-26 | 1993-04-27 | 1993-10-27 | $7700.00 | Window Closed / Lapsed |