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US4074032A
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Manufacture of heat-stable brominated oligomers of monovinyl-aromatic compounds
Assignee: BASF SE
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Filing: 1976-07-14
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Granted: 1978-02-14
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Expires: 1996-07-14
Abstract
Abstract A process for the manufacture of heat-stable, brominated oligostyrenes by brominating selectively hydrogenated oligostyrenes in halogenated solvents in the presence of Lewis acids at from -25° to +20° C. The brominated oligomers are highly heat-stable and can be processed, by themselves or as components of mixtures with other thermoplastics, to give various shaped articles.
Inventors
- 👤 Herbert Naarmann
- 👤 Klaus Penzien
- 👤 Hermann Gausepohl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:38
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/093; C07C17/10; C07C17/12; C08; C08F; C08F8/00; C08F8/18; C08F8/20; C08F8/22
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
75 words
A process for the manufacture of heat-stable, brominated oligomers of monovinyl-aromatic compounds which comprises: dissolving selectively hydrogenated oligomers of the monovinyl-aromatic compounds a halogenated solvents; reacting the hydrogenated oligomers with bromine in the presence of a Lewis acid catalyst at a temperature of from -25° C to +20° C while starting the reaction solution; washing the reaction solution with water to eliminate bromide ions; and thereafter isolating the brominated reaction product from the reaction solution.
Claim 2
Dependent Claim
75 words
A process for the manufacture of heat-stable, brominated oligomers of monovinyl-aromatic compounds which comprises: dissolving selectively hydrogenated oligomers of the monovinyl-aromatic compounds a halogenated solvents; reacting the hydrogenated oligomers with bromine in the presence of a Lewis acid catalyst at a temperature of from -25° C to +20° C while starting the reaction solution; washing the reaction solution with water to eliminate bromide ions; and thereafter isolating the brominated reaction product from the reaction solution.
Claim 3
Dependent Claim
29 words
A process as set forth in claim 1, in which the selectively hydrogenated oligomers of the monovinyl-aromatic compounds have a molecular weight of from 400 to 8,000 before bromination.
Claim 4
Dependent Claim
30 words
A process set forth in claim 1, in which the selectively hydrogenated oligomers of the monovinyl-aromatic compounds are brominated to a bromide content of from 0.5 to 71% by weight.
Claim 5
Dependent Claim
37 words
A process set forth in claim 1, in which from 0.005 to 15% by weight of a high-boiling organic phosphite are added to the reaction solution after extraction with water but before isolating the brominated reaction product.
Claim 6
Dependent Claim
17 words
A process as set forth in claim 1 wherein the monovinyl-aromatic compound is a homo-oligomer of styrene.
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) | 1981-02-13 | 1981-08-15 | 1982-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-13 | 1985-08-15 | 1986-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-13 | 1989-08-15 | 1990-02-14 | $7700.00 | Window Closed / Lapsed |