US4059545A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crosslinked styrene polymer foam having suppressed ignition properties
Assignee: Dow Chemical Co
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Filing: 1975-12-22
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Granted: 1977-11-22
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Expires: 1995-12-22
Abstract
Abstract A monovinylidene aromatic polymer foam having reduced propensity to ignite is produced by (1) foaming a copolymer of monovinylidene aromatic monomer and an ethylenically unsaturated carboxylic anhydride wherein a portion of the copolymer contains halogen moiety and (2) subsequently crosslinking the copolymer foam by contacting it with a crosslinking agent such as alkylene polyamine. The resultant copolymer foam does not melt or drip upon exposure to flame.
Inventors
- 👤 John M. Corbett
- 👤 Richard E. Skochdopole
- 👤 Anthony L. Scaggs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:12
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J2325/00; Y; Y10; Y10S; Y10S521/00; Y10S521/907
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
81 words
A non-melting copolymer foam of a monovinylidene aromatic monomer and an ethylenically unsaturated carboxylic anhydride, said copolymer having chemically bonded thereto an amount of a halogenated moiety containing chlorine and/or bromine sufficient to reduce the propensity of the copolymer to propagate combustion, said copolymer containing at least 1 milliequivalent of anhydride moiety per gram of copolymer, and said copolymer being crosslinked with a polyfunctional compound through the anhydride moiety to a degree sufficient to render it non-melting upon exposure to flame.
Claim 2
Dependent Claim
81 words
A non-melting copolymer foam of a monovinylidene aromatic monomer and an ethylenically unsaturated carboxylic anhydride, said copolymer having chemically bonded thereto an amount of a halogenated moiety containing chlorine and/or bromine sufficient to reduce the propensity of the copolymer to propagate combustion, said copolymer containing at least 1 milliequivalent of anhydride moiety per gram of copolymer, and said copolymer being crosslinked with a polyfunctional compound through the anhydride moiety to a degree sufficient to render it non-melting upon exposure to flame.
Claim 3
Dependent Claim
25 words
The copolymer foam of claim 1 wherein crosslinking is effected by contacting the copolymer with a gaseous polyamine containing at least 2 primary amino groups.
Claim 4
Dependent Claim
32 words
The copolymer foam of claim 2 which is a copolymer of styrene and maleic anhydride wherein the anhydride is partially esterified with alcohol containing chlorine and/or bromine to provide said halogenated moiety.
Claim 5
Dependent Claim
14 words
The copolymer foam of claim 3 wherein the alcohol is a brominated aliphatic alcohol.
Claim 6
Dependent Claim
13 words
The copolymer foam of claim 4 wherein the brominated aliphatic alcohol is 2,2,2-tris(bromomethyl)ethanol.
Claim 7
Dependent Claim
14 words
The copolymer foam of claim 3 wherein the alcohol is a brominated aromatic alcohol.
Claim 8
Dependent Claim
13 words
The copolymer foam of claim 6 wherein the brominated aromatic alcohol is tribromophenoxyethanol.
Claim 9
Dependent Claim
11 words
The copolymer foam of claim 2 wherein the polyamine is ethylenediamine.
Claim 10
Dependent Claim
13 words
The copolymer foam of claim 1 wherein the monovinylidene aromatic monomer is ar-bromostyrene.
Claim 11
Dependent Claim
34 words
The copolymer foam of claim 1 wherein the copolymer contains (1) from about 15 to about 45 weight percent bromine and (2) at least about 1 milliequivalent of anhydride moiety per gram of copolymer.
Claim 12
Dependent Claim
41 words
The copolymer foam of claim 2 wherein the copolymer is a copolymer containing from about 40 to about 90 weight percent of copolymerized monovinylidene aromatic monomer and from about 10 to about 50 weight percent of copolymerized α,β-ethylenically unsaturated carboxylic anhydride.
Claim 13
Dependent Claim
34 words
The copolymer foam of claim 11 wherein the copolymer contains from about 45 to about 88 weight percent of copolymerized styrene and from about 12 to about 32 weight percent of copolymerized maleic anhydride.
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) | 1980-11-21 | 1981-05-23 | 1981-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-21 | 1985-05-23 | 1985-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-21 | 1989-05-23 | 1989-11-22 | $7700.00 | Window Closed / Lapsed |