CA1124947A - Process for the manufacture of brominated products of polystyrene - Google Patents
Process for the manufacture of brominated products of polystyreneInfo
- Publication number
- CA1124947A CA1124947A CA351,279A CA351279A CA1124947A CA 1124947 A CA1124947 A CA 1124947A CA 351279 A CA351279 A CA 351279A CA 1124947 A CA1124947 A CA 1124947A
- Authority
- CA
- Canada
- Prior art keywords
- polystyrene
- iron
- bromine
- process according
- catalyst
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
- C08F8/18—Introducing halogen atoms or halogen-containing groups
- C08F8/20—Halogenation
- C08F8/22—Halogenation by reaction with free halogens
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- General Chemical & Material Sciences (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Treatments Of Macromolecular Shaped Articles (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Polyoxymethylene Polymers And Polymers With Carbon-To-Carbon Bonds (AREA)
- Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
Abstract
Case 3-12341/CGM 229/1+2 Process for the manufacture of brominated products of polystyrene Abstract of the Disclosure The direct bromination at low temperature, in a partially halogenated hydrocarbon as solvent and in the presence of a divalent and/or trivalent iron salt or iron oxide as catalyst, of polystyrene which has been obtained by radically initiated polymerisation, results in thermally stable, soluble and uncrosslinked polystyrene products with a high bromine content and at most an insignificant natural colour. These brominated polystyrenes are useful in particular as flame retardants for plastics.
Description
11249~7 Case 3-12341/CGM 229/1+2 Process for the manufacture of brominated products of polystyrene The present invention relates to a process for the manufacture, by direct bromination, of brominated products of polystyrene obtained by radically initiated polymerisation, said products having a high bromine content.
The halogenation of polystyrenes is desirable whenever it is intended that the final products should have flame-resistant properties. A relatively low bromine content usually suffices for this purpose. However, if it is desired to incorporate halogenated polystyrene as flame retardant in other plastics, a high bromine content is advantageous in order that only small amounts of flame retardant may be used. For this utility, the halogenated polystyrene should have at most an insignificant natural colour and sufficient thermal stability.
The direct bromination at low temperature,and using relatively short reaction times,of polystyrenes obtain~d by radically initiated polymerisation to produce products having the desired properties, has proved to be an insoluble problem. It is, however, most desirable, as the use of these commercially available polystyrenes would be more economic. The known difficulties which occur in the direct bromination of these polystyrenes in halogen-containing solvents at low temperature and in the presence of a Lewis acid catalyst, are described e.g. in German Auslegeschrift 2 537 385 and German Offenlegungsschrift , 9~
llZ49~7
The halogenation of polystyrenes is desirable whenever it is intended that the final products should have flame-resistant properties. A relatively low bromine content usually suffices for this purpose. However, if it is desired to incorporate halogenated polystyrene as flame retardant in other plastics, a high bromine content is advantageous in order that only small amounts of flame retardant may be used. For this utility, the halogenated polystyrene should have at most an insignificant natural colour and sufficient thermal stability.
The direct bromination at low temperature,and using relatively short reaction times,of polystyrenes obtain~d by radically initiated polymerisation to produce products having the desired properties, has proved to be an insoluble problem. It is, however, most desirable, as the use of these commercially available polystyrenes would be more economic. The known difficulties which occur in the direct bromination of these polystyrenes in halogen-containing solvents at low temperature and in the presence of a Lewis acid catalyst, are described e.g. in German Auslegeschrift 2 537 385 and German Offenlegungsschrift , 9~
llZ49~7
2 651 435: premature precipitation by gel formation, low bromine content of the products, pronounced natural colour, and thermal instability. These disadvantages are overcome in the prior art by reacting selectively hydrogenated oligomers of styrene,or polystyrene freshly prepared by cationic polymerisation, with bromine.
It is known from Chemical Abstracts77,75 880 k (1972) and 85,6331 k (1976) to carry out the direct bromination of polystyrene in CC14 at elevated temperature in the presence of iron as catalyst. Although a premature gel formation is prevented in this physiologically hazardous solvent, a noticeable and undesirable reduction in the molecular weight of the brominated polystyrene is observed.
It has also been found that, at low temperature, only an insufficient bromine content is obtained.
Accordingly, it is the object of the present invention to provide a process for the direct bromination of commercially available polystyrene, i.e. polystyrene obtained by radically initiated polymerisation, which process overcomes the disadvantages referred to and yields thermally stable brominated products having at most an insignificant natural colour, a high bromine content, and good solubility in the reaction medium.
The present invention therefore relates to a process for the manufacture of brominated products of polystyrene which contain at least 50% by weight of bromine, by direct bromination of polystyrene obtained by radically initiated polymerisation, in solution and in the presence of a Lewis acid catalyst at low temperature, which process comprises carrying out the bromination in a partially halogenated 112494~
hydrocarbon as solvent, in the presence of a divalent and/or trivalent iron salt as catalyst, in the temperature range from -30 to +30C.
It is preferred to use bromine or bromine chloride as brominating agent in the direct bromination. The bromine chloride can be obtained in known manner, e.g. by continuously adding bromine and passing a flow of chlorine gas through the reaction solution. This procedure may also result in the formation to an insignificant degree of chlorinated final products.
The process of the invention affords the particular advantage that it is possible to use essentially polystyrene which is ready prepared and commercially available. The brominated polystyrenes obtained in the process of this invention have a bromine content of preferably at least 55% by weight, most preferably of at least 60% by weight.
The degree of polymerisation of the polystyrene employed is preferably at least 100 and is especially between 500 and 2500, most preferably between 1000 and 2500. Partially halogenated hydrocarbons are used as solvents. These can have aromatic and especially aliphatic or cycloaliphatic character and additionally contain at least one hydrogen atom in the molecule. Preferred halogens are bromine, fluorine and especially chlorine. The use of readily volatile halogenated hydrocarbons is also advantageous, as they are easiest to remove from the products obtained.
Examples of such solvents are: chloroform, methylene chloride, dibromomethane, chloroethane, bromoethane, dibromoethane, chlorobenzene, hexafluorobenzene, as well as correspondingly mixed halogenated hydrocarbons or mixtures of partially halogenated hydrocarbons. Preferred solvents are methylene chloride and 1,2-dichloroethane.
llZ4947 The amount of polystyrene is not crucial for the process. It is advantageous to employ an amount of 5 to 60% by weight, based on the reaction solution.
Divalent and/or trivalent iron salts or oxides are used as catalysts. These can be both salts of inorganic and organic acids and complex salts. Examples are: iron fluoride, iron chloride, iron bromide, iron sulfate, iron nitrate, iron phosphate, iron oxalate, iron acetate or iron benzoate, as well as hexacyanoferrate and iron oxides such as Fe304. When using an iron bromide, it is especially advantageous to form this in situ by reacting iron with bromine. Iron is therefore used in this case, and the catalytically active iron bromide is formed during the bromination. The catalyst is normally used in an amount of 0.05 to 20V/o by weight, with the preferred amount being from 0.5 to 5% by weight, based on the polystyrene employed.
Preferred catalysts are iron halides, especially FeC13, and iron. However, very good results are also obtained by substituting other iron salts for these catalysts in the process of the invention.
The bromination is preferably carried out in the temperature range from 0 to 25C in apparatus ordinarily used for the purpose. To avoid secondary reactions, it is advantageous to perform the reaction while excluding light.
The reaction can be performed e.g. by dissolving the polystyrene in the partially halogenated hydrocarbon, then adding the catalyst, e.g. iron powder. Then, while excluding light and with stirring and cooling, the required amount of bromine, if desired dissolved in the same solvent, 11~4947 is slowly added dropwise. The reaction mixture can be stirred for a time in order to bring the reaction to completion.
The reaction mixture is worked up by conventional methods. Excess bromine can be removed by a reducing agent, e.g. an aqueous hydrogen sulfite solution. The reaction solution is then washed free of bromide with water. The brominated polystyrene can then be isolated by removing the solvent e.g. by distillation. However, it is also possible to precipitate the brominated polystyrene from the solution by addition of a polar solvent e.g. an alcohol. The isolated brominated polystyrene can then be dried at elevated temperature and in vacuo in order to remove the solvent more completely.
The brominated polystyrenes obtained by the process of this invention are soluble, uncrosslinked thermoplastic products which are distinguished by a high bromine content, an insignificant natural colour, and very good thermal stability. Surprisingly, these products are obtained by the process o~f the invention using radically polymerised polystyrene as simple starting material. These brominated polystyrenes are useful flame retardants for plastics, especially for thermoplastics.
The invention is illustrated in more detail by the following Examples.
11~4947 Example 1: 26 g of commercially available polystyrene (Hostyren N 5000) are dissolved in 600 ml of methylene chloride. After addition of 0.5 g of iron powder, 99.8 g of bromine are slowly added dropwise at 0C while excluding light and with stirring and cooling. After stirring for 6 hours at 0C, the methylene chloride solution is stirred at room temperature with 100 ml of 3% sodium hydrogen sulfite solution and then washed free of bromide with water (S x 500 ml). The methylene chloride solution is then poured into lS00 ml of methanol with stirring.
The precipitated product is filtered with suction and dried for 12 hours at 60C/1 mbar, affording 59 g of brominated polystyrene in the form of a colourless powder with a bromine content of 64.9%. The product starts to decompose at 315C (determination by thermogravimetric analysis).
Example 2: 26 g of commercially available polystyrene are dissolved in 600 ml of methylene chloride. After addition of 1 g of iron powder, 99.8 g of bromine are added slowly dropwise at 15-20C while excluding light and with stirring and cooling. After stirring for 6 hours at 15-20C, the reaction mixture is washed free of bromide as in Example 1. The methylene chloride solution is concentrated and the residue is kept for a further hour at 250C/10 mbar, affording 61 g of slightly yellowish brominated polystyrene with a bromine content of 64.4 % by weight. The product starts to decompose at 325C
(determination by thermogravimetric analysis).
Example 3: 26 g of commercially available polystyrene are dissolved in 600 ml of dichloroethane. After addition of 1 g of iron powder, 99.8 g of bromine are slowly added 11~4947 dropwise at 15-20C while excluding light and with stirring and cooling. After atirring for 6 hours at 15-20C, the reaction mixture is washed free of bromide as in Example 1. Precipitation of the polymer solution in methanol yields 58 g of almost colourless polystyrene with a bromine content of 64.3% by weight. The product starts to decompose at 305C (determination by thermogravimetric analysis).
Example 4: 26 g of commercially available polystyrene are dissolved in 600 ml of methylene chloride. After addition of 0.5 g of iron powder, 79.9 g of bromine are slowly added dropwise at -10C while excluding light and with stirring and cooling. After stirring for 24 hours at -10C, the reaction mixture is washed free of bromide as in Example 1. Precipitation of the polymer solution in methanol yields 55 g of almost colourless brominated polystyrene with a bromine content of 61.6% by weight.
The product starts to decompose at 325C (determination by thermogravimetric analysis).
Example 5: 26 g of commercially available polystyrene are dissolved in 300 ml of methylene chloride. After addition of 4 g of FeP04, 79.9 g of bromine are slowly added dropwise at 0C while excluding light and with stirring and cooling. After stirring for 24 hours at 0C, the reaction mixture is washed free of bromide as in Example 1. Precipitation yields 62 g of brominated polystyrene in the form of a yellowish powder with a bromine content of 62.4% by weight. The product starts to decompose at 318C(determination by thermogravimetric analysis).
11~4947 Example 6: 26 g of commercially available polystyrene are dissolved in 300 ml of methylene chloride. After addition of 2 g of dried Fe(II) oxalate (10 hours/140C/l mbar), 51.3 g of bromine and 21.3 g of chlorine are added at 0C
in the course of 4 hours while excluding light and with stirring and cooling. The addition of the halogens is made as follows: first only bromine (1 hour), later bromine and chlorine simultaneously (2 hours) and finally only chlorine (1 hour). The reaction mixture is stirred for 18 hours, then washed free of bromide as in Example 1 and worked up, affording 69.6 g of brominated polystyrene in the form of a yellowish powder with a bromine content of 63.3% by weight and a chlorine content of 0.9% by weight.
The product starts to decompose at 349C (determination by thermogravimetric analysis).
Example 7: 26 g of commercially available polystyrene are dissolved in 300 ml of methylene chloride. After addition of 2 g of finely powdered Fe304, 51.3 g of bromine and 21.3 g of chlorine are added in the manner described in Example 6. The reaction mixture is stirred for 18 hours and worked up as in Example 1, affording 72.6 g of bromin-ated polystyrene in the form of a yellowish powder with a bromine content of 64.0% by weight and a chlorine content of 1.2% by weight. The product starts to decompose at 334C (determination by thermogravimetric analysis).
Comparison Example: 26 g of commercially available polystyrene are brominated as described in Example 1 using CCl4 as solvent. The brominated polystyrene has a bromine content of only 45% by weight.
It is known from Chemical Abstracts77,75 880 k (1972) and 85,6331 k (1976) to carry out the direct bromination of polystyrene in CC14 at elevated temperature in the presence of iron as catalyst. Although a premature gel formation is prevented in this physiologically hazardous solvent, a noticeable and undesirable reduction in the molecular weight of the brominated polystyrene is observed.
It has also been found that, at low temperature, only an insufficient bromine content is obtained.
Accordingly, it is the object of the present invention to provide a process for the direct bromination of commercially available polystyrene, i.e. polystyrene obtained by radically initiated polymerisation, which process overcomes the disadvantages referred to and yields thermally stable brominated products having at most an insignificant natural colour, a high bromine content, and good solubility in the reaction medium.
The present invention therefore relates to a process for the manufacture of brominated products of polystyrene which contain at least 50% by weight of bromine, by direct bromination of polystyrene obtained by radically initiated polymerisation, in solution and in the presence of a Lewis acid catalyst at low temperature, which process comprises carrying out the bromination in a partially halogenated 112494~
hydrocarbon as solvent, in the presence of a divalent and/or trivalent iron salt as catalyst, in the temperature range from -30 to +30C.
It is preferred to use bromine or bromine chloride as brominating agent in the direct bromination. The bromine chloride can be obtained in known manner, e.g. by continuously adding bromine and passing a flow of chlorine gas through the reaction solution. This procedure may also result in the formation to an insignificant degree of chlorinated final products.
The process of the invention affords the particular advantage that it is possible to use essentially polystyrene which is ready prepared and commercially available. The brominated polystyrenes obtained in the process of this invention have a bromine content of preferably at least 55% by weight, most preferably of at least 60% by weight.
The degree of polymerisation of the polystyrene employed is preferably at least 100 and is especially between 500 and 2500, most preferably between 1000 and 2500. Partially halogenated hydrocarbons are used as solvents. These can have aromatic and especially aliphatic or cycloaliphatic character and additionally contain at least one hydrogen atom in the molecule. Preferred halogens are bromine, fluorine and especially chlorine. The use of readily volatile halogenated hydrocarbons is also advantageous, as they are easiest to remove from the products obtained.
Examples of such solvents are: chloroform, methylene chloride, dibromomethane, chloroethane, bromoethane, dibromoethane, chlorobenzene, hexafluorobenzene, as well as correspondingly mixed halogenated hydrocarbons or mixtures of partially halogenated hydrocarbons. Preferred solvents are methylene chloride and 1,2-dichloroethane.
llZ4947 The amount of polystyrene is not crucial for the process. It is advantageous to employ an amount of 5 to 60% by weight, based on the reaction solution.
Divalent and/or trivalent iron salts or oxides are used as catalysts. These can be both salts of inorganic and organic acids and complex salts. Examples are: iron fluoride, iron chloride, iron bromide, iron sulfate, iron nitrate, iron phosphate, iron oxalate, iron acetate or iron benzoate, as well as hexacyanoferrate and iron oxides such as Fe304. When using an iron bromide, it is especially advantageous to form this in situ by reacting iron with bromine. Iron is therefore used in this case, and the catalytically active iron bromide is formed during the bromination. The catalyst is normally used in an amount of 0.05 to 20V/o by weight, with the preferred amount being from 0.5 to 5% by weight, based on the polystyrene employed.
Preferred catalysts are iron halides, especially FeC13, and iron. However, very good results are also obtained by substituting other iron salts for these catalysts in the process of the invention.
The bromination is preferably carried out in the temperature range from 0 to 25C in apparatus ordinarily used for the purpose. To avoid secondary reactions, it is advantageous to perform the reaction while excluding light.
The reaction can be performed e.g. by dissolving the polystyrene in the partially halogenated hydrocarbon, then adding the catalyst, e.g. iron powder. Then, while excluding light and with stirring and cooling, the required amount of bromine, if desired dissolved in the same solvent, 11~4947 is slowly added dropwise. The reaction mixture can be stirred for a time in order to bring the reaction to completion.
The reaction mixture is worked up by conventional methods. Excess bromine can be removed by a reducing agent, e.g. an aqueous hydrogen sulfite solution. The reaction solution is then washed free of bromide with water. The brominated polystyrene can then be isolated by removing the solvent e.g. by distillation. However, it is also possible to precipitate the brominated polystyrene from the solution by addition of a polar solvent e.g. an alcohol. The isolated brominated polystyrene can then be dried at elevated temperature and in vacuo in order to remove the solvent more completely.
The brominated polystyrenes obtained by the process of this invention are soluble, uncrosslinked thermoplastic products which are distinguished by a high bromine content, an insignificant natural colour, and very good thermal stability. Surprisingly, these products are obtained by the process o~f the invention using radically polymerised polystyrene as simple starting material. These brominated polystyrenes are useful flame retardants for plastics, especially for thermoplastics.
The invention is illustrated in more detail by the following Examples.
11~4947 Example 1: 26 g of commercially available polystyrene (Hostyren N 5000) are dissolved in 600 ml of methylene chloride. After addition of 0.5 g of iron powder, 99.8 g of bromine are slowly added dropwise at 0C while excluding light and with stirring and cooling. After stirring for 6 hours at 0C, the methylene chloride solution is stirred at room temperature with 100 ml of 3% sodium hydrogen sulfite solution and then washed free of bromide with water (S x 500 ml). The methylene chloride solution is then poured into lS00 ml of methanol with stirring.
The precipitated product is filtered with suction and dried for 12 hours at 60C/1 mbar, affording 59 g of brominated polystyrene in the form of a colourless powder with a bromine content of 64.9%. The product starts to decompose at 315C (determination by thermogravimetric analysis).
Example 2: 26 g of commercially available polystyrene are dissolved in 600 ml of methylene chloride. After addition of 1 g of iron powder, 99.8 g of bromine are added slowly dropwise at 15-20C while excluding light and with stirring and cooling. After stirring for 6 hours at 15-20C, the reaction mixture is washed free of bromide as in Example 1. The methylene chloride solution is concentrated and the residue is kept for a further hour at 250C/10 mbar, affording 61 g of slightly yellowish brominated polystyrene with a bromine content of 64.4 % by weight. The product starts to decompose at 325C
(determination by thermogravimetric analysis).
Example 3: 26 g of commercially available polystyrene are dissolved in 600 ml of dichloroethane. After addition of 1 g of iron powder, 99.8 g of bromine are slowly added 11~4947 dropwise at 15-20C while excluding light and with stirring and cooling. After atirring for 6 hours at 15-20C, the reaction mixture is washed free of bromide as in Example 1. Precipitation of the polymer solution in methanol yields 58 g of almost colourless polystyrene with a bromine content of 64.3% by weight. The product starts to decompose at 305C (determination by thermogravimetric analysis).
Example 4: 26 g of commercially available polystyrene are dissolved in 600 ml of methylene chloride. After addition of 0.5 g of iron powder, 79.9 g of bromine are slowly added dropwise at -10C while excluding light and with stirring and cooling. After stirring for 24 hours at -10C, the reaction mixture is washed free of bromide as in Example 1. Precipitation of the polymer solution in methanol yields 55 g of almost colourless brominated polystyrene with a bromine content of 61.6% by weight.
The product starts to decompose at 325C (determination by thermogravimetric analysis).
Example 5: 26 g of commercially available polystyrene are dissolved in 300 ml of methylene chloride. After addition of 4 g of FeP04, 79.9 g of bromine are slowly added dropwise at 0C while excluding light and with stirring and cooling. After stirring for 24 hours at 0C, the reaction mixture is washed free of bromide as in Example 1. Precipitation yields 62 g of brominated polystyrene in the form of a yellowish powder with a bromine content of 62.4% by weight. The product starts to decompose at 318C(determination by thermogravimetric analysis).
11~4947 Example 6: 26 g of commercially available polystyrene are dissolved in 300 ml of methylene chloride. After addition of 2 g of dried Fe(II) oxalate (10 hours/140C/l mbar), 51.3 g of bromine and 21.3 g of chlorine are added at 0C
in the course of 4 hours while excluding light and with stirring and cooling. The addition of the halogens is made as follows: first only bromine (1 hour), later bromine and chlorine simultaneously (2 hours) and finally only chlorine (1 hour). The reaction mixture is stirred for 18 hours, then washed free of bromide as in Example 1 and worked up, affording 69.6 g of brominated polystyrene in the form of a yellowish powder with a bromine content of 63.3% by weight and a chlorine content of 0.9% by weight.
The product starts to decompose at 349C (determination by thermogravimetric analysis).
Example 7: 26 g of commercially available polystyrene are dissolved in 300 ml of methylene chloride. After addition of 2 g of finely powdered Fe304, 51.3 g of bromine and 21.3 g of chlorine are added in the manner described in Example 6. The reaction mixture is stirred for 18 hours and worked up as in Example 1, affording 72.6 g of bromin-ated polystyrene in the form of a yellowish powder with a bromine content of 64.0% by weight and a chlorine content of 1.2% by weight. The product starts to decompose at 334C (determination by thermogravimetric analysis).
Comparison Example: 26 g of commercially available polystyrene are brominated as described in Example 1 using CCl4 as solvent. The brominated polystyrene has a bromine content of only 45% by weight.
Claims (9)
1. A process for the manufacture of brominated products of polystyrene,said products containing at least 50% by weight of bromine, by direct bromination of polystyrene obtained by radically initiated polymerisation, in solution and in the presence of a Lewis acid catalyst at low temperature, which process comprises carrying out the bromination in a partially halogenated hydrocarbon as solvent, in the presence of a divalent and/or trivalent iron salt or oxide as catalyst, in the temperature range from -30° to +30°C.
2. A process according to claim 1, wherein the solvent is a partially chlorinated aliphatic hydrocarbon.
3. A process according to claim 2, wherein the solvent is 1,2-dichloroethane or methylene chloride.
4. A process according to claim 1, wherein the iron salt is used in an amount of 0.05 to 20% by weight, based on the polystyrene.
5. A process according to claim 1, wherein an iron halide is used as catalyst.
6. A process according to claim 1, wherein the reaction temperature is in the range from 0° to 25°C.
7. A process according to claim 1, wherein the direct bromination is carried out with bromine or bromine chloride.
8. A process according to claim 1, wherein an iron salt is used as catalyst.
9. A process according to claim 1, wherein the catalyst is iron(II) oxalate, iron(III) phosphate or iron(III) oxide.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH4256/79-0 | 1979-05-07 | ||
| CH425679 | 1979-05-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1124947A true CA1124947A (en) | 1982-06-01 |
Family
ID=4272723
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA351,279A Expired CA1124947A (en) | 1979-05-07 | 1980-05-05 | Process for the manufacture of brominated products of polystyrene |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0020294B1 (en) |
| JP (1) | JPS55151007A (en) |
| AT (1) | ATE1781T1 (en) |
| BR (1) | BR8002787A (en) |
| CA (1) | CA1124947A (en) |
| DE (1) | DE3061057D1 (en) |
| ES (1) | ES491190A0 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4879353A (en) * | 1987-01-28 | 1989-11-07 | Great Lakes Chemical Corporation | Bromination of polystyrene using bromine as the reaction solvent |
| US7632893B2 (en) | 2005-06-30 | 2009-12-15 | Albemarle Corporation | Brominated styrenic polymers and their preparation |
Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0611856B2 (en) * | 1983-10-25 | 1994-02-16 | 三菱瓦斯化学株式会社 | Flame-retardant polyphenylene ether resin composition |
| EP0201411A3 (en) * | 1985-05-03 | 1989-02-08 | The Dow Chemical Company | Brominated polymers of alkenyl aromatic compounds |
| JPH02215807A (en) * | 1989-02-17 | 1990-08-28 | Nippon Kayaku Co Ltd | Preparation of brominated polystyrene |
| US5637650A (en) | 1996-06-14 | 1997-06-10 | Ferro Corporation | Brominated polysytrene having improved thermal stability and color and process for the preparation thereof |
| US6518368B2 (en) | 1996-06-14 | 2003-02-11 | Albemarle Corporation | Brominated polystyrene having improved thermal stability and color and process for the preparation thereof |
| US6235844B1 (en) | 1996-09-26 | 2001-05-22 | Albemarle Corporation | Brominated polystyrenic resins |
| US6232408B1 (en) | 1996-09-26 | 2001-05-15 | Albemarle Corporation | Brominated polstyrenic resins |
| US6326439B1 (en) | 1996-09-26 | 2001-12-04 | Albemarle Corporation | Process for brominating polystyrenic resins |
| US6133381A (en) * | 1996-09-26 | 2000-10-17 | Albelmarle Corporation | Brominated polystyrenic flame retardants |
| JP4328388B2 (en) | 1996-09-26 | 2009-09-09 | アルベマール・コーポレーシヨン | Method for brominating styrene polymers |
| US6521714B2 (en) | 1996-09-26 | 2003-02-18 | Albemarle Corporation | Brominated polystyrenic resins |
| US5767203A (en) * | 1996-09-26 | 1998-06-16 | Albemarle Corporation | Process for brominated styrenic polymers |
| US6235831B1 (en) | 1996-09-26 | 2001-05-22 | Albemarle Corporation | Polymer compositions containing brominated polystyrenic resins |
| US6232393B1 (en) | 1996-09-26 | 2001-05-15 | Albemarle Corporation | Polymers flame retarded with brominated polystyrenic resins |
| CN105504106A (en) * | 2015-12-24 | 2016-04-20 | 深圳爱易瑞科技有限公司 | Brominated polystyrene with high thermal stability and preparation method of brominated polystyrene |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2651435C3 (en) * | 1976-11-11 | 1980-11-27 | Basf Ag, 6700 Ludwigshafen | Process for the preparation of brominated styrene polymerization products |
| DE2800012B2 (en) * | 1978-01-02 | 1981-08-13 | Chemische Werke Hüls AG, 4370 Marl | Process for the production of heat-resistant, core-brominated polystyrenes |
-
1980
- 1980-04-30 EP EP80810143A patent/EP0020294B1/en not_active Expired
- 1980-04-30 AT AT80810143T patent/ATE1781T1/en not_active IP Right Cessation
- 1980-04-30 DE DE8080810143T patent/DE3061057D1/en not_active Expired
- 1980-05-05 CA CA351,279A patent/CA1124947A/en not_active Expired
- 1980-05-06 ES ES491190A patent/ES491190A0/en active Granted
- 1980-05-06 BR BR8002787A patent/BR8002787A/en unknown
- 1980-05-07 JP JP6048580A patent/JPS55151007A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4879353A (en) * | 1987-01-28 | 1989-11-07 | Great Lakes Chemical Corporation | Bromination of polystyrene using bromine as the reaction solvent |
| US7632893B2 (en) | 2005-06-30 | 2009-12-15 | Albemarle Corporation | Brominated styrenic polymers and their preparation |
| US8168723B2 (en) | 2005-06-30 | 2012-05-01 | Albemarle Corporation | Brominated styrenic polymers and their preparation |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0020294A1 (en) | 1980-12-10 |
| BR8002787A (en) | 1980-12-16 |
| ATE1781T1 (en) | 1982-11-15 |
| ES8104339A1 (en) | 1981-04-16 |
| DE3061057D1 (en) | 1982-12-16 |
| ES491190A0 (en) | 1981-04-16 |
| JPS55151007A (en) | 1980-11-25 |
| EP0020294B1 (en) | 1982-11-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1124947A (en) | Process for the manufacture of brominated products of polystyrene | |
| EP1032602B9 (en) | Process for the preparation of brominated polystyrene having improved color characteristics | |
| Howells et al. | Trifluoromethanesulfonic acid and derivatives | |
| US4200703A (en) | Process for the manufacture of heat-stable, nuclear-brominated polystyrenes | |
| US4879353A (en) | Bromination of polystyrene using bromine as the reaction solvent | |
| EP0277429B1 (en) | Aromatic bromination of polystyrene using bromine as the reaction solvent | |
| EP0063874A1 (en) | Production of aromatic polyketones | |
| US4568700A (en) | Process for the production of halomethylating agents which are of low volatility | |
| DE2517142C2 (en) | ||
| US4522952A (en) | Process for the fluorination of polymers, and perfluorinated ion exchangers | |
| CA1037642A (en) | Process for the chloromethylation of styrene-divinylbenzene copolymers | |
| Zefirov et al. | Oxidatively assisted nucleophilic substitution of iodine in alkyl iodides by nucleofugic anions | |
| JPH10158202A (en) | Production of diphenylethane bromide | |
| Seyferth et al. | Communications-The Action of Phenyllithium on Bromomethyl-and Iodomethyltriphenylphosphonium Halides | |
| US4054596A (en) | Carboxy and carbohydrocarbyloxy-substituted 1,1-bis(perfluoroalkylsulfonyl)propanes | |
| CA1038525A (en) | Method for producing bis-(bromomethyl)-tetrachlorobenzenes and the use thereof as a fireproofing agent | |
| CA1158381A (en) | Thermally stable smoke suppressant additives to polymeric compositions | |
| Boudakian et al. | Reactions of pyrosulfuryl fluoride | |
| EP0023014B1 (en) | Process for preparing hexafluoropropene oxide | |
| DE2725124A1 (en) | CROSS-LINKED SULPHONATED STYRENE HOMO OR MIXED POLYMERIZES AND PROCESS FOR THEIR PRODUCTION | |
| JP3674196B2 (en) | Method for producing brominated polystyrene | |
| US4351776A (en) | Preparation of iodophthalonitrile | |
| US3935251A (en) | 2,4,8-Trichloro-tri and tetra bromodibenzofurans | |
| US3448159A (en) | Ethyl vinyl sulfone production | |
| US4473710A (en) | Process for the synthesis of tertiary phosphine oxides, and new tertiary phosphine oxides |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |