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US4576991A
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UV-Resistant flame retardant compositions of polycarbonates and halogenated alkenyl aromatic copolymers
Assignee: General Electric Co
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Filing: 1984-06-25
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Granted: 1986-03-18
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Expires: 2004-06-25
Abstract
Abstract Flame retardant blends of an aromatic polycarbonate, preferably a tetraalkylsubstituted aromatic polycarbonate, and a copolymer of an alkenyl aromatic compound and a halogenated alkenyl aromatic compound are described. The ultraviolet light resistance and impact strength of articles molded from such compositions is superior to that of moldings prepared from corresponding blends of the polycarbonate, a polystyrene homopolymer and a conventional low molecular weight halogenated flame retardant agent.
Inventors
- 👤 Glenn D. Cooper, deceased
- 👤 Sai-Pei Ting
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:03
CPC Classifications
C; C08; C08L; C08L25/00; C08L25/18; C08L69/00
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
149 words
A flame retardant thermoplastic composition, comprising: (a) an aromatic polycarbonate consisting essentially of a tetraalkyl-substituted aromatic polycarbonate; and (b) a copolymer consisting of units of a non-halogenated alkenyl aromatic compound having the formula ##STR7## wherein R 1 , R 2 , R 3 , R 4 , R 5 and R 6 selected from the group consisting of hydrogen and lower alkyl groups having from 1 to 6 carbon atoms; and units of a brominated alkenyl aromatic compound having the formula ##STR8## wherein R 7 and R 8 are selected from the group consisting of hydrogen and lower alkyl groups having from 1 to 6 carbon atoms, R 9 is bromine and, R 10 , R 11 are selected from the group consisting of hydrogen, bromine and lower alkyl groups having from 1 to 6 carbon atoms, and n represents the number of R 9 substituents on the ring.
Claim 2
Dependent Claim
149 words
A flame retardant thermoplastic composition, comprising: (a) an aromatic polycarbonate consisting essentially of a tetraalkyl-substituted aromatic polycarbonate; and (b) a copolymer consisting of units of a non-halogenated alkenyl aromatic compound having the formula ##STR7## wherein R 1 , R 2 , R 3 , R 4 , R 5 and R 6 selected from the group consisting of hydrogen and lower alkyl groups having from 1 to 6 carbon atoms; and units of a brominated alkenyl aromatic compound having the formula ##STR8## wherein R 7 and R 8 are selected from the group consisting of hydrogen and lower alkyl groups having from 1 to 6 carbon atoms, R 9 is bromine and, R 10 , R 11 are selected from the group consisting of hydrogen, bromine and lower alkyl groups having from 1 to 6 carbon atoms, and n represents the number of R 9 substituents on the ring.
Claim 3
Dependent Claim
65 words
A composition according to claim 1, in which in component (a) at least 50 percent of the linear chains comprise units of the formula ##STR9## in which R represents C 1 -C 3 alkyl and X represents a single bond, --O--, --CO--, --SO--, C 1 -C 10 alkylene, C 1 -C 10 alkylidene, C 5 -C 15 cycloalkylene, C 5 -C 15 cycloalkylidene, or ##STR10##
Claim 4
Dependent Claim
15 words
A composition according to claim 1, in which component (a) is an 0,0,0',0'-tetraalkyl-substituted bisphenol-A polycarbonate.
Claim 5
Dependent Claim
15 words
A composition according to claim 3, in which component (a) is an 0,0,0',0'-tetramethyl-substituted bisphenol-A polycarbonate.
Claim 6
Dependent Claim
13 words
A composition according to claim 1, in which component (b) is rubber modified.
Claim 7
Dependent Claim
24 words
A composition according to claim 1, in which component (b) comprises from about 10 to about 90 percent by weight of the brominated units.
Claim 8
Dependent Claim
24 words
A composition according to claim 1, in which component (b) comprises from about 35 to about 70 percent by weight of the brominated units.
Claim 9
Dependent Claim
17 words
A composition according to claim 1, in which component (b) is a copolymer of styrene and bromostyrene.
Claim 10
Dependent Claim
20 words
A composition according to claim 1, in which component (b) is a polybutadiene rubber modified copolymer of styrene and bromostyrene.
Claim 11
Dependent Claim
31 words
A composition according to claim 1, which includes one or more additives selected from the group consisting of flame retardant agents, mineral fillers, fibrous reinforcing agents, plasticizers, colorants and impact modifiers.
Claim 12
Dependent Claim
51 words
A flame retardant thermoplastic molding composition, comprising (a) from 10 to 90 parts by weight of an aromatic polycarbonate derived from 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane; and (b) from 90 to 10 parts by weight of a copolymer of styrene and bromostyrene containing from about 35 to about 70 percent by weight of the bromostyrene.
Claim 13
Dependent Claim
51 words
A flame retardant thermoplastic molding composition, comprising (a) from 10 to 90 parts by weight of an aromatic polycarbonate derived from 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane; and (b) from 90 to 10 parts by weight of a copolymer of styrene and bromostyrene containing from about 35 to about 70 percent by weight of the bromostyrene.
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) | 1989-03-17 | 1989-09-16 | 1990-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-17 | 1993-09-16 | 1994-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-17 | 1997-09-16 | 1998-03-18 | $7700.00 | Window Closed / Lapsed |