Preparation method of polyphenylene sulfide

Abstract

The invention relates to the field of high molecular material synthesis, in particular to a preparation method of polyphenylene sulfide. The preparation method comprises the following steps of: adding Na2S.9H2O, N-methyl pyrrolidone and a reaction assistant into a polymerization kettle, supplying nitrogen to replace air, then heating to 180 DEG C for dehydration at a dehydration rate of 80-95%, adding an N-methylpyrrolidine solution containing p-dichlorobenzene into a dehydrated system in Step (1) for reaction for 3-8h at 190-230 DEG C, after the reaction finishes, obtaining a size mixture, filtering the size mixture, adding a filter cake into boiled pure water, stirring, washing, and performing 90Hz ultrasonic treatment for 15-30min, repeatedly washing for 2-3 times, and obtaining PPS (polyphenylene sulfide) resin after drying. The method has the advantageous effects that the product hue can be obviously improved since sodium thiosulfate is added, even a water content of the system is higher (the dehydration rate is 80%) and the reaction temperature is higher, and the ultrasonic washing can effectively remove inorganic salt impurities included due to macromolecular chain bending and winding in a reaction process.

Description

technical field [0001] The invention relates to the field of polymer material synthesis, more specifically a preparation method of polyphenylene sulfide. Background technique [0002] Polyphenylene sulfide (PPS) is a new type of engineering plastic with excellent performance that was produced in the 1970s and developed rapidly. It has excellent properties such as molding processability, thermal stability, chemical corrosion resistance, physical and mechanical properties, electrical conductivity, low toxicity, heat resistance, and flame retardancy, so it is widely used in mechanical chemical industry, electrical industry, automobile industry, aviation, food processing, etc. Widely used in various fields. [0003] The Philips method is the earliest method to realize industrialized production in the world, and it is also the most mainstream industrialized production method at present. The process is to dissolve p-dichlorobenzene (P-DCB) and sodium sulfide or sodium bisulfide...

AI Technical Summary

Problems solved by technology

Hexamethylphosphoric triamide (HMPA) is better as a solvent than N-methylpyrrolidone (NMP), but it is expensive and consumes too much

[0005]Philips method has easy-to-obtain raw materials, high yield, and better product quality than other processes, but this process also has its disadvantages. The price of the solvent N-methylpyrrolidone (NMP) Expensive, high consumption; NMP itself is reactive and will form PPS with pyrrolidone end groups, which will affect the solvent resistance of PPS; high temperature and pressure reaction will promote the decomposition of solvent NMP, and the solvent recovery rate is low