The present invention provides a method for producing granular polyarylene sulfide (PAS) with increased average particle size and enhanced particle strength, a method for increasing the average particle size of granular PAS, a method for enhancing the particle strength of granular PAS, and granular PAS. The method for producing PAS according to the present invention includes: step 1: a preparation step of preparing a mixture containing an organic amide solvent, a sulfur source, water, a dihalo aromatic compound, and an alkali metal hydroxide; step 2: a pre-stage polymerization step of initiating a polymerization reaction by heating the mixture to produce a prepolymer having a dihalo aromatic compound conversion ratio of not less than 50% in the presence of less than an equimolar amount of an alkali metal hydroxide per 1 mol of the sulfur source; step 3: a post-stage polymerization step of continuing the polymerization reaction in the presence of not less than an equimolar amount of an alkali metal hydroxide per 1 mol of the sulfur source to obtain a reaction product mixture; and step 4: a cooling step of cooling the reaction product mixture after the post-stage polymerization step; wherein step 4 is performed in the presence of at least one type of auxiliary agent such as a carboxylate.

The present invention provides a method for producing granular polyarylene sulfide (PAS) with increased average particle size and enhanced particle strength, a method for increasing the average particle size of granular PAS, a method for enhancing the particle strength of granular PAS, and granular PAS. The method for producing PAS according to the present invention includes: step 1: a preparation step of preparing a mixture containing an organic amide solvent, a sulfur source, water, a dihalo aromatic compound, and an alkali metal hydroxide; step 2: a pre-stage polymerization step of initiating a polymerization reaction by heating the mixture to produce a prepolymer having a dihalo aromatic compound conversion ratio of not less than 50% in the presence of less than an equimolar amount of an alkali metal hydroxide per 1 mol of the sulfur source; step 3: a post-stage polymerization step of continuing the polymerization reaction in the presence of not less than an equimolar amount of an alkali metal hydroxide per 1 mol of the sulfur source to obtain a reaction product mixture; and step 4: a cooling step of cooling the reaction product mixture after the post-stage polymerization step; wherein step 4 is performed in the presence of at least one type of auxiliary agent such as a carboxylate.

Provided is a continuous production apparatus and a continuous production method capable of preventing the countercurrent of evaporation components generated at the time of polymerization so that continuous solution polymerization reactions can progress reliably. A continuous production apparatus (100) includes a housing chamber (2) configured to house a plurality of reaction vessels (1a to 1d); wherein a reaction mixture is formed by subjecting monomers to a polymerization reaction in a solvent in at least one of the reaction vessels; the reaction vessels communicate with one another via a gas phase part (4); the reaction vessels are sequentially connected; the reaction mixture successively moves to each of the reaction vessels; and the housing chamber includes a baffle (9) configured to narrow the cross-sectional area of the gas phase part at the boundary between at least one pair of adjacent reaction vessels or in the vicinity of the boundary.

A continuous production device and a continuous production method which are configured to produce a polymer and can efficiently advance solution polycondensation with a simple device configuration which is easy to wash and maintenance. A continuous production device (100) includes a reactor main body (1), divider plates (6a to 6c) configured to divide the interior of the reactor main body into a plurality of reaction vessels (2a to 2d), and a raw material supply unit. The divider plate has a rotation center. Gas-phase parts of the reaction vessels adjacent to each other are communicating with each other, and liquid-phase parts of the reaction vessels adjacent to each other are communicating with each other. A reaction mixture generated in the reaction vessel sequentially moves through the reaction vessels.

A continuous production device and a continuous production method which are configured to produce a polymer and can efficiently advance solution polycondensation with a simple device configuration which is easy to wash and maintenance. A continuous production device (100) includes a reactor main body (1), divider plates (6a to 6c) configured to divide the interior of the reactor main body into a plurality of reaction vessels (2a to 2d), and a raw material supply unit. The divider plate has a rotation center. Gas-phase parts of the reaction vessels adjacent to each other are communicating with each other, and liquid-phase parts of the reaction vessels adjacent to each other are communicating with each other. A reaction mixture generated in the reaction vessel sequentially moves through the reaction vessels.

A method for producing polyarylene sulfide of the present invention includes the steps of: supplying reaction raw materials to at least one of a plurality of reaction vessels mutually communicated through a gas phase; carrying out a polymerization reaction; and removing at least some of the water present in the reaction vessels. Each of the steps is carried out in parallel, and a reaction mixture is transferred sequentially between the reaction vessels. At that time, the amount of heat that is removed in the polymerization reaction is less than the amount of reaction heat of the polymerization reaction.

A method for producing polyarylene sulfide of the present invention includes the steps of: supplying reaction raw materials to at least one of a plurality of reaction vessels mutually communicated through a gas phase; carrying out a polymerization reaction; and removing at least some of the water present in the reaction vessels. Each of the steps is carried out in parallel, and a reaction mixture is transferred sequentially between the reaction vessels. At that time, the amount of heat that is removed in the polymerization reaction is less than the amount of reaction heat of the polymerization reaction.

The present invention relates to a method of preparing a polyphenylene sulfide and a high-viscosity polyphenylene sulfide prepared using the method. In this method, the ratio of an organic phase to an aqueous phase is controlled by controlling dehydration conditions, so that high viscosity may be realized without adversely affecting a reaction or physical properties during preparation of the polyphenylene sulfide.

Provided is a PAS production method and a PAS production apparatus wherein, in a gas-liquid system including a gas phase containing water, a dihalo aromatic compound, and hydrogen sulfide and a liquid phase containing a polar organic solvent and PAS, the dihalo aromatic compound and the hydrogen sulfide that can be volatilized at the time of dehydration from the gas phase can be recovered. The PAS production method according to the present invention includes: a condensation step of obtaining a first intermediate gas phase containing a dihalo aromatic compound and hydrogen sulfide and a first intermediate liquid phase containing water, a dihalo aromatic compound, and a sulfur source by condensation from the gas phase in the gas-liquid; a first recovery step of bringing the first intermediate gas phase into contact with a polar organic solvent to obtain a first recovered gas phase containing hydrogen sulfide and a first recovered liquid phase containing a polar organic solvent, a dihalo aromatic compound, and a sulfur source; and a second recovery step of bringing the first recovered gas phase into contact with an alkali metal hydroxide aqueous solution to obtain a second recovered liquid phase containing water, a sulfur source, and an alkali metal hydroxide.

Provided is a PAS production method and a PAS production apparatus wherein, in a gas-liquid system including a gas phase containing water, a dihalo aromatic compound, and hydrogen sulfide and a liquid phase containing a polar organic solvent and PAS, the dihalo aromatic compound and the hydrogen sulfide that can be volatilized at the time of dehydration from the gas phase can be recovered. The PAS production method according to the present invention includes: a condensation step of obtaining a first intermediate gas phase containing a dihalo aromatic compound and hydrogen sulfide and a first intermediate liquid phase containing water, a dihalo aromatic compound, and a sulfur source by condensation from the gas phase in the gas-liquid; a first recovery step of bringing the first intermediate gas phase into contact with a polar organic solvent to obtain a first recovered gas phase containing hydrogen sulfide and a first recovered liquid phase containing a polar organic solvent, a dihalo aromatic compound, and a sulfur source; and a second recovery step of bringing the first recovered gas phase into contact with an alkali metal hydroxide aqueous solution to obtain a second recovered liquid phase containing water, a sulfur source, and an alkali metal hydroxide.