US4294954A
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Polycarbonate copolymers
Assignee: General Electric Co
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Filing: 1979-12-13
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Granted: 1981-10-13
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Expires: 1999-12-13
Abstract
Abstract Polycarbonate copolymers are provided consisting essentially of chemically combined bisphenol carbonate units and having from about 5 to 70 mole percent of such chemically combined bisphenol carbonate units in the form of o,p'-bisphenol dichloroethylene carbonate units. The polycarbonate copolymers have been found to possess valuable flame retardant properties and improved processability.
Inventors
- 👤 Charles M. Orlando
- 👤 George R. Loucks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:32
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/04; Y; Y10; Y10S; Y10S260/00; Y10S260/24
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
66 words
Polycarbonates consisting essentially of about (a) 5 to 70 mole percent of carbonate units of the formula, ##STR12## chemically combined with about (b) 95 to 30 mole percent of carbonate units of the formula, ##STR13## where R is a C.sub.(6-13) divalent aromatic organic radical, Z is a member selected from --S--, --O--, ##STR14## and a C.sub.(4-8) cycloaliphatic radical and a is equal to 0 or 1.
Claim 2
Dependent Claim
66 words
Polycarbonates consisting essentially of about (a) 5 to 70 mole percent of carbonate units of the formula, ##STR12## chemically combined with about (b) 95 to 30 mole percent of carbonate units of the formula, ##STR13## where R is a C.sub.(6-13) divalent aromatic organic radical, Z is a member selected from --S--, --O--, ##STR14## and a C.sub.(4-8) cycloaliphatic radical and a is equal to 0 or 1.
Claim 3
Dependent Claim
36 words
Polycarbonates consisting essentially of from about (a) 5 to 70 mole percent of carbonate units of the formula, ##STR15## chemically combined with about (b) 95 to 30 mole percent of carbonate units of the formula, ##STR16##
Claim 4
Dependent Claim
36 words
Polycarbonates consisting essentially of from about (a) 5 to 70 mole percent of carbonate units of the formula, ##STR15## chemically combined with about (b) 95 to 30 mole percent of carbonate units of the formula, ##STR16##
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) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |