Preparation method of 4, 4'-dichlorodiphenyl sulfone

Abstract

The invention discloses a preparation method of 4, 4'-dichlorodiphenyl sulfone. The method comprises the following steps: with chlorobenzene and parachlorobenzenesulfonyl chloride as raw materials, reacting in the presence of a catalyst and a small amount of polymerization inhibitor to obtain the 4, 4'-dichlorodiphenyl sulfone. A finished product with purity larger than 99.5% and yield larger than 90.0%is obtained by decolorization and recrystallization. The preparation method disclosed by the invention is simple in raw materials, and the use of a strong acid is avoided to reduce the corrosion on equipment; little equipment is involved in the whole process, so that the production cost is reduced; the generated HCl gas can be absorbed by alkali liquor and chloride obtained by treatment can be comprehensively used, thus the method is environment-friendly; the catalyst AlCl3 is cheap and available and the reaction time is greatly shortened; the reaction can be carried out at a low temperature, thereby reducing the generation of byproducts in the reaction process and improving the percent conversion of the product; the aftertreatment process is simplified, the yield is high and the purity is high, so that the preparation method is suitable for industrial production.

Description

technical field [0001] The invention belongs to the field of chemical synthesis, in particular to a preparation method of 4,4'-dichlorodiphenyl sulfone. Background technique [0002] Sulfone polymer materials such as polysulfone, polyethersulfone, polyarylsulfone, etc. are a class of aromatic non-crystalline high-performance thermoplastic engineering plastics containing sulfone groups on the main chain of the molecule, which have excellent heat resistance, physical and mechanical properties. , insulation properties, chemical resistance properties, so it has been widely used in various important industrial fields and daily life (patent CN1623982A). [0003] 4,4'-Dichlorodiphenylsulfone (DDS for short) is the main intermediate for the manufacture of new special engineering plastics such as polysulfone and polyarylethersulfone. Its manufacturing cost and product quality are the basis for the development of sulfone polymer materials; At the same time, it is also the raw materia...

AI Technical Summary

Problems solved by technology

Although this method has low production cost and simple raw materials, the reaction temperature is high, the reaction pressure is high, the conversion rate is low, and the reaction time is long (patent CN102304073A)

The sulfur trioxide method first makes chlorobenzene and SO 3 The reaction produces p-chlorobenzenesulfonic acid, and then with SOCl 2 Carry out acyl chloride reaction, use DMF, dimethyl sulfoxide, etc. as catalysts, react at 155 °C for 4 hours to generate p-chlorobenzenesulfonyl chloride, and finally react with chlorobenzene, use FeCl 3 , SbCl 5 4,4′-dichlorodiphenyl sulfone is obtained by reacting at 150-160°C for 7 hours. The yield is relatively high, but the reaction time is long, the equipment is seriously corroded, the entire process route is long, and the refining process route is complicated, etc. Disadvantages (patent CN102304072A)

The reaction needs to be carried out under microwave conditions, which requires high equipment in industrial applications, is difficult to realize, and isomers are easily generated, and the product quality is not high; the patent CN102295588A of Wujiang Beiku Shengyuan Textile Auxiliary Factory first uses chlorobenzene and React fuming sulfuric acid at 90-100°C for 5 hours to produce p-chlorobenzenesulfonic acid, and then use the complex acid composed of polyphosphoric acid and phosphorus pentoxide as a catalyst to react with chlorobenzene at about 60°C for 7-8 hours to obtain 4 , 4′-dichlorodiphenyl sulfone, the production cost of this method is higher, the production cycle is longer, it is difficult to reach the requirement of industrial production; React at 60°C for 2 hours to prepare p-chlorobenzenesulfonyl chloride, and then use tris(trifluoromethyl)sulfonate bismuth and antimony pentachloride as catalysts to react with chlorobenzene for 3-5 hours to synthesize 4,4'-dichloro Diphenylsulfone

Although the Friedel-Crafts reaction can be completed at normal temperature, the reaction time is also shorter, but bismuth tris(trifluoromethylsulfonate) is expensive, and antimony pentachloride is a highly toxic chemical, so it is not suitable for large-scale industrial production ; Patent CN102351756A uses chlorobenzene and SOCl 2 As raw material, with AlCl 3 As a catalyst, first synthesize the intermediate 4,4'-dichlorodiphenylsulfoxide, and then use acetic acid as a catalyst to react with hydrogen peroxide to prepare 4,4'-dichlorodiphenylsulfone

Although the reaction conditions of this method are relatively mild and the reaction yield is high, there are disadvantages such as long reaction time, large amount of acetic acid, serious corrosion to equipment, and difficult post-processing.

[0006] In short, the above methods have problems such as high reaction temperature, long reaction cycle, large material consumption, strong corrosion to production equipment, dark color of the produced product, many impurities produced by side reactions, high manufacturing cost, and large amount of three wastes.

Moreover, the purity of 4,4'-dichlorodiphenylsulfone produced by these methods is generally below 99%, which is difficult to meet the requirements of producing high-quality polysulfone polymer materials

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