Polyphenylene sulfide production method

Abstract

The invention discloses a polyphenylene sulfide production method. The production method comprises the following steps: (1) firstly pumping an NMP solvent and liquid p-dichlorobenzene into a pre-dissolving vessel with a metering pump to carry out pre-dissolving to form a pre-solution, wherein the weight ratio of the NMP solvent to liquid p-dichlorobenzene added to the pre-dissolving vessel is 1 to (1-1.5); (2) then adding the NMP solvent to a reaction kettle with the metering pump, then adding water-containing sodium sulfide and an alkali chloride catalyst to the reaction kettle, then filling nitrogen, raising the temperature to 170-195 DEG C and maintaining the temperature for 20-30 minutes and removing the moisture, wherein the weight ratio of water-containing sodium sulfide to the alkali chloride catalyst to liquid p-dichlorobenzene is 1 to (0.2-0.5) to (1.1-1.3); (3) after dehydration is completed, adding the NMP solvent to the reaction kettle with the metering pump, then heating the materials to 170-195 DEG C and then stopping filling nitrogen; (4) pumping the pre-solution into the reaction kettle with the metering pump; (5) raising the temperature to 280-300 DEG C to carry out condensation polymerization to generate polyphenylene sulfide. The production method has the advantage of quickness and safety in production of polyphenylene sulfide.

Description

technical field [0001] The invention relates to a production method of polyphenylene sulfide. Background technique [0002] The sodium sulfide method is a commonly used production method of polyphenylene sulfide at home and abroad. The raw materials used to prepare polyphenylene sulfide in the sodium sulfide method currently used are sodium sulfide and solid p-dichlorobenzene, and the solvent used is N- Methylpyrrolidone (NMP for short). The production steps of the currently used sodium sulfide method are: first add water-containing sodium sulfide, part of NMP solvent, and catalyst in the reactor, then raise the temperature to dehydrate the water-containing sodium sulfide, cool down after the dehydration finishes, and then dehydrate the solid state to two Chlorobenzene is added into the reactor, and then the remaining NMP solvent is added, and then the temperature is raised to carry out polycondensation reaction to produce polyphenylene sulfide. The disadvantages of the ab...

AI Technical Summary

Problems solved by technology

The disadvantages of the above-mentioned production method are: (1) It is a large amount of labor for workers to add solid p-dichlorobenzene; (2) it is not easy to accurately control the dosage of solid p-dichlorobenzene; (3) because solid p-dichlorobenzene is volatile Toxic p-dichlorobenzene gas is produced, which is very easy to cause harm to the health of feeding workers; (4) solid p-dichlorobenzene is injected into the reactor from the top of the reactor at one time, and cannot be in good contact with sodium sulfide, and will (5) During the process of putting solid p-dichlorobenzene into the reactor, it is easy to bring part of the air into the reactor, so that sodium sulfide and other substances are easily oxidized and deteriorated under high temperature conditions, which affects the performance of the polycondensation reaction. went smoothly