Production process for synthetizing brominated SBS (Styrene-butadiene-styrene block copolymer) by one-step method

Abstract

The invention discloses a production process for synthetizing brominated SBS (Styrene-butadiene-styrene block copolymer) by a one-step method, and belongs to the technical field of production of the brominated SBS. The production process comprises the following steps: dissolving SBS by an organic solvent; adding a brominating agent diluted by the organic solvent, wherein the brominating agent adopts a mixture of bromine and tribromide, and the tribromide is trimethylphenylammonium tribromide; adding a catalyst, wherein the catalyst is tin tetrachloride, the bromination reaction temperature is10 to 40 DEG C, and the reaction time is 2 to 8 h; sequentially performing decolourization, water washing and crystallization treatment on material liquid obtained after a reaction is finished; and then pouring crystallization materials into a centrifugal machine, centrifuging, then performing water washing, filtering and drying to a brominated SBS product. The bromine and few tribromides are added in a production process as the brominating agents; by adding a proper number of catalysts, a hydrogen bond substitution reaction is inhibited, and an addition reaction is given priority to; side reactions are reduced; the product structure is more stable; the heat stability of the brominated SBS is improved; the reaction is a one-step method production technique; and the production efficiency isimproved.

Description

technical field [0001] The invention relates to the technical field of brominated SBS production, in particular to a production process for one-step synthesis of brominated SBS. Background technique [0002] Brominated SBS, as a new environmentally friendly brominated flame retardant, is easier to shape in mechanical processing than hexabromocyclododecane, and brominated SBS is in the process conditions of melting mixture, injection molding, and extruding foam. The bearing capacity is very small, almost no thermal degradation, the process temperature can reach above 230°C, and the thermal stability is good. In addition, its flame retardant compatibility is good, and it will not have a negative impact on the mechanical properties of the added material. It was then determined by the US Environmental Protection Agency as a safe substitute for the flame retardant hexabromocyclododecane. [0003] There are many types of brominating agents to choose from in the existing brominate...

AI Technical Summary

Problems solved by technology

[0003] There are many types of brominating agents to choose from in the existing brominated SBS synthesis method, but there are still some problems, such as directly using bromine as the brominating agent, bromine has high energy, lively properties, and is very easy to bond with hydrogen in SBS A substitution reaction occurs, thereby inhibiting its addition reaction with the double bond in SBS, resulting in an increase in side reactions. Because of its imperfect structure, it further causes thermal weight loss to decrease and thermal stability to deteriorate; while only using a brominating agent to react Sometimes, the cost is high, the process steps are cumbersome, and often the reaction requires a two-step method, which affects production efficiency

In addition, the bromination reaction is rapid and the degree of reaction is difficult to control, resulting in incomplete reaction, and the resulting brominated SBS product has poor thermal stability and cannot meet the needs of use, which limits the large-scale production and general application of brominated SBS