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 are a method of producing a polyarylene sulfide (PAS) by a polymerization reaction of a sulfur source and a dihalo aromatic compound in an organic amide solvent, in which the PAS having a high degree of polymerization can be obtained at a high yield and the generation of a byproduct that imposes a large burden of a waste treatment can be effectively reduced; and a PAS having a high degree of polymerization.

The method of producing a PAS includes a preparation step of preparing a charged mixture containing an organic amide solvent, a sulfur source, water, and a dihalo aromatic compound; a first-stage polymerization step of performing a polymerization reaction on the charged mixture at a temperature of from 170 to 280 C. to produce a prepolymer having a conversion ratio of the dihalo aromatic compound of 50% or greater; and a second-stage polymerization step of continuing the polymerization reaction in a phase-separated state at a temperature of from 245 to 290 C. in a reaction system containing the prepolymer, and includes adding a polyfunctional compound to the reaction system in the phase-separated state. A PAS having a melt viscosity (310 C., shear rate: 1216 sec.sup.1) of from 0.1 to 8000 Pa.Math.s is produced by the method.

Provided are a method of producing a polyarylene sulfide (PAS) by a polymerization reaction of a sulfur source and a dihalo aromatic compound in an organic amide solvent, in which the PAS having a high degree of polymerization can be obtained at a high yield and the generation of a byproduct that imposes a large burden of a waste treatment can be effectively reduced; and a PAS having a high degree of polymerization.

The method of producing a PAS includes a preparation step of preparing a charged mixture containing an organic amide solvent, a sulfur source, water, and a dihalo aromatic compound; a first-stage polymerization step of performing a polymerization reaction on the charged mixture at a temperature of from 170 to 280 C. to produce a prepolymer having a conversion ratio of the dihalo aromatic compound of 50% or greater; and a second-stage polymerization step of continuing the polymerization reaction in a phase-separated state at a temperature of from 245 to 290 C. in a reaction system containing the prepolymer, and includes adding a polyfunctional compound to the reaction system in the phase-separated state. A PAS having a melt viscosity (310 C., shear rate: 1216 sec.sup.1) of from 0.1 to 8000 Pa.Math.s is produced by the method.

The present invention relates to a polyarylene sulfide which has more improved compatibility with other polymer materials or fillers, and a method for preparing the same. The polyarylene sulfide is characterized in that at least part of end groups of the main chain of the polyarylene sulfide is hydroxyl group (OH), the polyarylene sulfide contains iodine bonded to its main chain and free iodine, and the content of iodine bonded to the main chain and free iodine is 10 to 10,000 ppmw.

The present invention relates to a polyarylene sulfide which has more improved compatibility with other polymer materials or fillers, and a method for preparing the same. The polyarylene sulfide is characterized in that at least part of end groups of the main chain of the polyarylene sulfide is hydroxyl group (OH), the polyarylene sulfide contains iodine bonded to its main chain and free iodine, and the content of iodine bonded to the main chain and free iodine is 10 to 10,000 ppmw.

The present invention relates to a polyarylene sulfide-based resin composition, which has excellent thermal conduction efficiency in the horizontal and vertical directions and excellent mechanical properties such as tensile strength and impact strength, and to a molded article thereof.

The present invention relates to a polyarylene sulfide-based resin composition, which has excellent thermal conduction efficiency in the horizontal and vertical directions and excellent mechanical properties such as tensile strength and impact strength, and to a molded article thereof.

A resin composition which comprises a polyarylene sulfide resin having a reduced chlorine content and a reduced sodium content and a filler and is excellent in weld strength and moist heat resistance while it retains the excellent characteristic properties of the polyarylene sulfide resin. The resin composition comprises 100 parts by weight of the polyarylene sulfide resin (component A) and 10 to 300 parts by weight of the filler (component B) and has a total chlorine content of not more than 500 ppm and a total sodium content of not more than 39 ppm.

The present invention provides an a polyarylene sulfide (PAS) production device provided with a supply tube for loading corrosive materials such as a strong alkali into a reaction vessel, wherein prescribed amounts of various raw materials or the like can be accurately loaded into the reaction vessel without causing decreases in production efficiency due to the replacement of the supply tube or the repair of the reaction vessel in response to the corrosion of the supply tube or the like. The present invention is a production device, and a PAS production device, in particular, provided with a reaction vessel equipped with one or a plurality of supply tubes, at least one of the supply tubes having an insert pipe, which is preferably detachable, to be inserted into an outer supply tube; and a tip opening of the insert pipe being positioned further inward than an inside wall of the reaction vessel.