Method for preparing flame retardant brominated polystyrene by using composite catalyst

A technology for brominated polystyrene and polystyrene, which is applied in the field of preparing brominated polystyrene with composite catalysts, and can solve the problem of low melting point

Inactive Publication Date: 2005-06-29
EAST CHINA UNIV OF SCI & TECH
View PDF1 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0010] The most important defect of the brominated polystyrene obtained by the prior art is that the melting point is low (200~220°C)

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0017] Said brominated polystyrene preparation method of the present invention comprises the steps:

[0018] Dissolve polystyrene (molecular weight 500-1,500,000) in haloalkane solvent to make 5-20 wt% (optimally 5-10%) polystyrene solution, add 0.1-30 wt% polystyrene weight to the solution % (the best is 0.2~5%) dehydrating agent and the weight is the composite catalyst of polystyrene weight 0.01~20% (the best is 0.1~5%), at -20~80 ℃ (the best is 0~20 ℃) condition, drop brominating agent, the molar ratio of brominating agent and polystyrene is 1:1~3.5 (the best is 1:2~3.3), react for 1~20 hours (in 3~5 hours should) add sodium hydroxide or sodium bisulfite solution to terminate the reaction, wash with water or alkaline solution until neutral, then add the organic phase dropwise to alcohol to precipitate brominated polystyrene, filter and dry to obtain the target product.

[0019] The present invention is a method for preparing flame retardant brominated polystyrene in the pr...

Embodiment 1

[0022] Weigh 10.4g (0.1 mol in terms of styrene repeating unit) polystyrene and add it into a 250ml four-necked bottle equipped with a mechanical stirrer, a thermometer, a dropping funnel and a condenser tube, add solvent 100ml1,2-dichloroethane ( EDC) to make it dissolve, and add 0.4g phosphorus pentoxide for dehydration, after the polystyrene is completely dissolved, add 0.1g antimony trichloride and 0.025g zinc powder, after lowering the temperature to 0°C, slowly dissolve 43.6g liquid bromine Add it dropwise to the reaction solution. After the dropwise addition, raise the temperature to 10°C and keep it warm for 3 hours. After the reaction is over, wash the catalyst and dehydrating agent with water. After the water and oil are completely separated, add the organic phase to ethanol to precipitate the product. After filtering and drying, 30.5 g of brominated polystyrene was obtained, the product yield was 95%, the bromine content was 68%, and the melting point was 250°C.

Embodiment 2

[0024] Add 15.6g (0.15 moles in terms of styrene units) polystyrene into a 500ml four-neck flask equipped with a stirrer, thermometer, funnel and condenser tube, add 200ml of solvent 1,2-dichloroethane (EDC) to dissolve it , and add 0.5g of phosphorus pentoxide for dehydration, after the polystyrene is completely dissolved, add 0.2g of aluminum trichloride and 0.04g of nickel powder, adjust the temperature to 10°C, slowly add 65g of liquid bromine dropwise into the reaction solution After the dropwise addition, continue for 2 hours. After the reaction is completed, wash the catalyst and dehydrating agent with water. After the water and oil are completely separated, add the organic phase to methanol to precipitate the product, filter and dry to obtain 47g of brominated polystyrene, and the product is recovered The rate is 98%, the bromine content is 68.5%, and the melting point is 255°C.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Melting pointaaaaaaaaaa
Melting pointaaaaaaaaaa
Melting pointaaaaaaaaaa
Login to view more

Abstract

The invention relates to a method to prepare polystyrene bromide with compound catalyst system. Use polystyrene as the raw material, alkyl halide as solvent, with the existence of catalyst and dehydrating agent, the polystyrene bromide is made by bromination of brominating agent. Its characteristics include: the catalyst is composed of ó° family metal, ó�B family metal, tin or stibium and lewis acid, and the polystyrene bromide has large content of bromine (the largest-one can be 60%), high melt point (30-50% higher) and productivity (larger than 95%). It can be applied for antiflaming of resin such as PET, PBT and nyloen nylon.

Description

technical field [0001] The invention relates to a preparation method of a brominated flame retardant, in particular to a method for preparing brominated polystyrene by using a composite catalyst. technical background [0002] Brominated polystyrene (BPS) has been widely used as a flame retardant in PET, PBT, polyphenylene ether, nylon 66, nylon 6, etc. , polyimide and thermosetting plastics such as syndiotactic polystyrene, unsaturated polyester and epoxy resin. [0003] The reported preparation methods of brominated polystyrene are summarized as follows: [0004] (1) Barda, Gray et al. describe a preparation method of a tribrominated polystyrene flame retardant in U.S. Patent (U.S.Pat 4,352,909), which uses a single Lewis acid (antimony trichloride) as a catalyst, in halogen Brominated polystyrene is prepared by reacting high molecular weight polystyrene resin with brominating agent (bromine chloride) in a hydrocarbon solvent. The bromine content of the final product is ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C08F8/20C08F112/08
Inventor 辛忠公维光
Owner EAST CHINA UNIV OF SCI & TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products