US4069288A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for preparing fire retardant molding compositions
Assignee: Bayer Antwerpen NV
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Filing: 1976-04-26
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Granted: 1978-01-17
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Expires: 1996-04-26
Abstract
Abstract Disclosed herein is a method for preparing fire retardant styrenic polymer molding compositions with improved impact strength which compositions contain a metal oxide and a halogenated fire retardant additive. The method comprises dispersing the metal oxide into a minor portion of the styrene polymer component using high intensity mixing and temperatures at or above the fusion temperature of the styrene polymer in order to obtain a uniform dispersion. The metal oxide-polystyrene dispersion is then blended with the other ingredients of the polyblend. The resulting blend is compounded at temperatures greater than 255 DEG C. and then comminuted to form a molding composition.
Inventors
- 👤 Raymond A. Barkhuff, Jr.
- 👤 William E. Sprenkle, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:58
CPC Classifications
C; C08; C08K; C08K13/00; C08K13/02; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08K5/00; C08K5/04; C08L; C08L25/00; C08L25/02; C08L25/04; C08L51/00; C08L51/04; C08L53/00; C08L53/02; C08L2201/00; C08L2201/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
121 words
An improved process for compounding fire retardant polystyrene compositions, which comprise a polystyrene component, a metal oxide and a fire retardant halogen additive which method comprises: A. mixing the metal oxide with a minor amount of the polystyrene component; B. subjecting the mixture to high intensity mixing at or above the fusion temperature of the polystyrene for a time sufficient to uniformly disperse the metal oxide in the molten polystyrene; C. comminuting the polystyrene-metal oxide mixture obtained in Step B above; D. blending the comminuted polystyrene-metal oxide mixture with the other ingredients of the composition; E. compounding the blend from (D) above at temperatures above 255° C. and below the temperature at which degradation occurs; and F. comminuting the compounded blend.
Claim 2
Dependent Claim
121 words
An improved process for compounding fire retardant polystyrene compositions, which comprise a polystyrene component, a metal oxide and a fire retardant halogen additive which method comprises: A. mixing the metal oxide with a minor amount of the polystyrene component; B. subjecting the mixture to high intensity mixing at or above the fusion temperature of the polystyrene for a time sufficient to uniformly disperse the metal oxide in the molten polystyrene; C. comminuting the polystyrene-metal oxide mixture obtained in Step B above; D. blending the comminuted polystyrene-metal oxide mixture with the other ingredients of the composition; E. compounding the blend from (D) above at temperatures above 255° C. and below the temperature at which degradation occurs; and F. comminuting the compounded blend.
Claim 3
Dependent Claim
23 words
A process as in claim 1 wherein the polystyrene is modified with a diene rubber which has been grafted with a polystyrene superstrate.
Claim 4
Dependent Claim
20 words
A process as in claim 2 wherein the composition further contains a second rubber component which is a block copolymer.
Claim 5
Dependent Claim
33 words
A process as in claim 1 wherein the intensive mixing of the polystyrene component and the metal oxide is carried out at a temperature in the range of from 150° to 300° C.
Claim 6
Dependent Claim
23 words
A process as in claim 1 wherein the blend is extruded at a temperature in the range of from 260° to 290° C.
Claim 7
Dependent Claim
119 words
An improved method for compounding fire retardant polystyrene compositions, which comprise a polystyrene component, antimony oxide and a fire retardant halogen additive which method comprises: A. mixing the antimony oxide with a minor amount of the polystyrene component; B. subjecting the mixture to high intensity mixing at a temperature in the range of from 160° to 230° C. for a time sufficient to uniformly disperse the antimony oxide in the molten polystyrene; C. comminuting the mixture obtained in Step B above; D. blending the comminuted polystyrene-antimony oxide mixture with the other ingredients of the composition; E. extruding the blend from (D) above at temperatures in the range of from 260° to 290° C.; and F. comminuting the extruded blend.
Claim 8
Dependent Claim
119 words
An improved method for compounding fire retardant polystyrene compositions, which comprise a polystyrene component, antimony oxide and a fire retardant halogen additive which method comprises: A. mixing the antimony oxide with a minor amount of the polystyrene component; B. subjecting the mixture to high intensity mixing at a temperature in the range of from 160° to 230° C. for a time sufficient to uniformly disperse the antimony oxide in the molten polystyrene; C. comminuting the mixture obtained in Step B above; D. blending the comminuted polystyrene-antimony oxide mixture with the other ingredients of the composition; E. extruding the blend from (D) above at temperatures in the range of from 260° to 290° C.; and F. comminuting the extruded blend.
Claim 9
Dependent Claim
24 words
A process as in claim 6 wherein the polystyrene matrix is modified with a butadiene rubber which has been grafted with a polystyrene superstrate.
Claim 10
Dependent Claim
22 words
A process as in claim 7 wherein the composition further contains a second rubber component which is a styrene butadiene block copolymer.
Claim 11
Dependent Claim
20 words
A process as in claim 7 wherein the composition further contains a second rubber component which is a polychloroprene rubber.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-16 | 1981-07-18 | 1982-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-16 | 1985-07-18 | 1986-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-16 | 1989-07-18 | 1990-01-17 | $7700.00 | Window Closed / Lapsed |