US4624979A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flame retardant polyphenylene ether-polystyrene blends of increased heat resistance and method of achievement
Assignee: General Electric Co
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Filing: 1984-11-28
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Granted: 1986-11-25
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Expires: 2004-11-28
Abstract
Abstract A method for increasing the heat distortion temperature of certain blends of polyphenylene ether resin and styrene polymers is described in which an admixture is formed of a polyphenylene ether resin and a flame retardant copolymer of styrene and up to 50 percent dibromostyrene. The resulting compositions can be formulated to include one or more additional ingredients and are moldable into articles characterized by good flame retardancy and light stability, as well as a higher heat distortion temperature compared with articles formed from corresponding blends using homopolystyrene or styrene-bromostyrene copolymer.
Inventors
- 👤 Robert J. Axelrod
- 👤 Glenn D. Cooper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:27
CPC Classifications
C; C08; C08L; C08L25/00; C08L25/02; C08L25/04; C08L25/08; C08L25/18; C08L71/00; C08L71/08; C08L71/10; C08L71/12; C08L71/123
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
56 words
A method for increasing the heat distortion temperature after molding of a flame retardant blend of a polyphenylene ether resin and a styrene polymer, comprising forming a compatible admixture of a polyphenylene ether resin and a flame retardant copolymer of styrene and dibromostyrene, said copolymer containing no more than 50 percent by weight of the dibromostyrene.
Claim 2
Independent Claim
56 words
A method for increasing the heat distortion temperature after molding of a flame retardant blend of a polyphenylene ether resin and a styrene polymer, comprising forming a compatible admixture of a polyphenylene ether resin and a flame retardant copolymer of styrene and dibromostyrene, said copolymer containing no more than 50 percent by weight of the dibromostyrene.
Claim 3
Dependent Claim
35 words
A method according to claim 1, in which the admixture of a minor amount of polyphenylene ether resin and a major amount of styrene-dibromostyrene copolymer is formed by coprecipitating the two from a common solvent.
Claim 4
Dependent Claim
19 words
A method according to claim 1, in which the copolymer is comprised of greater than 30 percent of 3,4-dibromostyrene.
Claim 5
Dependent Claim
60 words
A method according to claim 1, in which the polyphenylene ether resin is a homopolymer or copolymer of the formula ##STR4## wherein Q, Q', Q" and Q'", are independently selected from the group consisting of hydrogen, halogen, hydrocarbon, halohydrocarbon, hydrocarbonoxy, and halohydrocarbonoxy; and n represents the total number of monomer units and is an integer of at least about 20.
Claim 6
Dependent Claim
16 words
A method according to claim 1, in which the polyphenylene ether resin is poly(2,6-dimethyl-1,4-phenylene ether) resin.
Claim 7
Dependent Claim
20 words
A method according to claim 1, which further comprises including at least one additional flame retardant agent in the blend.
Claim 8
Dependent Claim
17 words
A method according to claim 6, in which the additional flame retardant agent is an aromatic phosphate.
Claim 9
Dependent Claim
14 words
A method according to claim 7, in which the aromatic phosphate is triphenyl phosphate.
Claim 10
Dependent Claim
17 words
A method according to claim 1, which further comprises including an impact resistance improver in the blend.
Claim 11
Dependent Claim
16 words
A method according to claim 9, in which the impact improver is a styrene-butadiene elastomeric copolymer.
Claim 12
Dependent Claim
20 words
A method according to claim 1, which comprises the additional step of thermally forming the blend into a shaped article.
Claim 13
Dependent Claim
15 words
A method according to claim 1, in which the shaping is carried out by molding.
Claim 14
Dependent Claim
44 words
A flame retardant, light stable article produced by the method of claim 12, which is characterized by a higher heat distortion temperature in comparison with a corresponding article from a composition in which (b) is a homopolystyrene or a copolymer of styrene and monobromostyrene.
Claim 15
Dependent Claim
39 words
A flame retardant composition comprising a compatible admixture of (a) a polyphenylene ether resin; and (b) a flame retardant amount of a copolymer of styrene and dibromostyrene which contains no more than 50 percent by weight of the dibromostyrene.
Claim 16
Dependent Claim
39 words
A flame retardant composition comprising a compatible admixture of (a) a polyphenylene ether resin; and (b) a flame retardant amount of a copolymer of styrene and dibromostyrene which contains no more than 50 percent by weight of the dibromostyrene.
Claim 17
Dependent Claim
60 words
A composition according to claim 14, in which the polyphenylene ether resin is a homopolymer or copolymer of the formula ##STR5## wherein Q, Q', Q" and Q'" are independently selected from the group consisting of hydrogen, halogen, hydrocarbon, halohydrocarbon, hydrocarbonoxy, and halohydrocarbonoxy; and n represents the total number of monomer units and is an integer of at least about 20.
Claim 18
Dependent Claim
16 words
A composition according to claim 15, in which the polyphenylene ether resin is poly(2,6-dimethyl-1,4-phenylene ether) resin.
Claim 19
Dependent Claim
15 words
A composition according to claim 14, in which the copolymer contains 3,4-dibromostyrene or 2,4-dibromostyrene units.
Claim 20
Dependent Claim
16 words
A composition according to claim 14, in which includes at least one additional flame retardant agent.
Claim 21
Dependent Claim
16 words
A composition according to claim 18, in which the flame retardant agent is an aromatic phosphate.
Claim 22
Dependent Claim
14 words
A composition according to claim 19, in which the aromatic phosphate is triphenyl phosphate.
Claim 23
Dependent Claim
13 words
A composition according to claim 14, which includes an impact resistance improving polymer.
Claim 24
Dependent Claim
17 words
A composition according to claim 21, in which the impact resistance improver is a styrene-butadiene elastomeric copolymer.
Claim 25
Dependent Claim
11 words
A composition according to claim 14, which contains a mineral filler.
Claim 26
Dependent Claim
14 words
A composition according to claim 23, in which the mineral filler is titanium dioxide.
Claim 27
Dependent Claim
30 words
A method according to claim 1, in which the admixture of a minor amount of polyphenylene ether resin and a major amount of styrene-dibromostyrene copolymer is formed by melt blending.
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) | 1989-11-24 | 1990-05-26 | 1990-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-24 | 1994-05-26 | 1994-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-24 | 1998-05-26 | 1998-11-25 | $7700.00 | Window Closed / Lapsed |