A method of producing a polyarylene sulfide composed of amino groups, the method including allowing at least a dihalogenated aromatic compound, an inorganic sulfurizing agent and a compound (A) to react in an organic polar solvent and in the presence of an alkali metal hydroxide, wherein: said compound (A) is present in an amount of 0.04 moles or more and 0.5 moles or less with respect to 1 mole of said inorganic sulfurizing agent, in a reaction vessel; and said compound (A) is a compound comprising at least one aromatic ring, and having, on said one aromatic ring, an amino group, and at least one functional group selected from the group consisting of hydroxyl group, a salt of hydroxyl group, thiol group and a salt of thiol group.

To provide a method for producing PAS by which PAS having a small particle size of 50 μm or greater and 550 μm or less as an average particle size can be produced.

In the method for producing PAS, including: (1) a preparation step of preparing a prepared mixture containing an organic polar solvent, a sulfur source, and a dihalo aromatic compound; (2) a pre-stage polymerization step of initiating a polymerization reaction by heating the prepared mixture to produce a prepolymer; (3) a phase separation step of adding water as a phase separation agent to a reaction mixture in a reaction system to form a phase separation state; and (4) a post-stage polymerization step of continuing the polymerization reaction after the phase separation step, in which an organic sulfonic acid metal salt having a specific solubility in water is contained in the prepared mixture or the reaction mixture.

To provide a method for producing PAS by which PAS having a small particle size of 50 μm or greater and 550 μm or less as an average particle size can be produced.

In the method for producing PAS, including: (1) a preparation step of preparing a prepared mixture containing an organic polar solvent, a sulfur source, and a dihalo aromatic compound; (2) a pre-stage polymerization step of initiating a polymerization reaction by heating the prepared mixture to produce a prepolymer; (3) a phase separation step of adding water as a phase separation agent to a reaction mixture in a reaction system to form a phase separation state; and (4) a post-stage polymerization step of continuing the polymerization reaction after the phase separation step, in which an organic sulfonic acid metal salt having a specific solubility in water is contained in the prepared mixture or the reaction mixture.

Provided is a resin composition for molding containing a polyarylene sulfide resin that forms a molded body having all of mechanical strength, heat cycle characteristics, and thermal conductivity in a well-balanced manner. Specifically, provided are a resin composition for molding containing a plate-like filler having an aspect ratio of 10 to 500 (A), a polyarylene sulfide resin (B), a thermoplastic resin having a glass transition temperature (Tg) of 20° C. or lower (C), and glass fibers (D) as essential components, the plate-like filler (A) being contained in an amount of 30 to 70 parts by mass relative to 100 parts by mass of the sum of the plate-like filler (A), the polyarylene sulfide resin (B), the thermoplastic resin (C), and the glass fibers (D), and a molded body of the resin composition for molding.

A polymer (B) essentially contains units represented by the following formulas (1), (2) and (3), wherein the number of moles of unit (1) is 0 to 95, the number of moles of unit (2) is 0 to 50, and the number of moles of unit (3) is 2 to 80 when the total number of moles of units (1), (2) and (3) is 100:

##STR00001##

In units (1) to (3), “X” is a recurring unit having a benzene ring, in unit (2), —CH.sub.3 is substituted on the benzene ring, “m” is an integer of 1-6, unit (3) is obtained by substituting a hydrogen of —CH.sub.3 in unit (2) by a substituent “Z” derived from a carboxylic acid or anhydride thereof, “n” is an integer of 1-6 indicative of the number of substitutions, l+n=m, and unit (3) is a unit in which “n” is an integer of 1-6 or a combination thereof.

A polymer (B) essentially contains units represented by the following formulas (1), (2) and (3), wherein the number of moles of unit (1) is 0 to 95, the number of moles of unit (2) is 0 to 50, and the number of moles of unit (3) is 2 to 80 when the total number of moles of units (1), (2) and (3) is 100:

##STR00001##

In units (1) to (3), “X” is a recurring unit having a benzene ring, in unit (2), —CH.sub.3 is substituted on the benzene ring, “m” is an integer of 1-6, unit (3) is obtained by substituting a hydrogen of —CH.sub.3 in unit (2) by a substituent “Z” derived from a carboxylic acid or anhydride thereof, “n” is an integer of 1-6 indicative of the number of substitutions, l+n=m, and unit (3) is a unit in which “n” is an integer of 1-6 or a combination thereof.

A polyarylene sulfide in which when the cumulative integral value from the molecular weight of 100 to the molecular weight of 10,000 in a molecular weight distribution curve is 100, the cumulative integrated value at the molecular weight of 4000 is 48 to 53, and when the melt flow rate of the polyarylene sulfide is defined as MFR1, and when the melt flow rate obtained after mixing the polyarylene sulfide with an epoxy silane coupling agent at a weight ratio of 100:1 and heating the resulting mixture at 315.5° C. for 5 minutes is defined as MFR2, the rate of change represented by MFR2/MFR1 is not more than 0.085.

A polyarylene sulfide in which when the cumulative integral value from the molecular weight of 100 to the molecular weight of 10,000 in a molecular weight distribution curve is 100, the cumulative integrated value at the molecular weight of 4000 is 48 to 53, and when the melt flow rate of the polyarylene sulfide is defined as MFR1, and when the melt flow rate obtained after mixing the polyarylene sulfide with an epoxy silane coupling agent at a weight ratio of 100:1 and heating the resulting mixture at 315.5° C. for 5 minutes is defined as MFR2, the rate of change represented by MFR2/MFR1 is not more than 0.085.

A method of producing polyarylene sulfide (PAS) by subjecting a sulfur source and a dihalo aromatic compound (DHA) to polymerization reaction in an organic amide solvent under alkaline conditions, the method suppressing side reactions or the like and yielding PAS having a high degree of polymerization at a high yield is provided; and PAS having a high degree of polymerization are provided.

A method of producing PAS, including: a preparation step of preparing a preparation mixture containing an organic amide solvent, a sulfur source, an alkali metal hydroxide, water, and DHA, and having a pH of 12.5 or higher; a first-stage polymerization step of heating the preparation mixture to 170° C. or higher to initiate a polymerization reaction and continuing the polymerization reaction at 240 to 280° C., thereby forming a prepolymer having a DHA conversion rate of 50% or greater (at this time, a temperature increasing rate from 220° C. to 240° C. is lower than a temperature increasing rate for 240° C. or higher); and a second-stage polymerization step of adding, in the reaction system, an alkali metal hydroxide in an amount of 1 to 20 mol % per 1 mol of the sulfur source in the presence of a phase separation agent to continue the polymerization reaction at 245 to 290° C. PAS having a melt viscosity (310° C.; shear rate: 1216 sec.sup.-1) of 0.1 to 8000 Pa.Math.s produced by the method.

A method of producing polyarylene sulfide (PAS) by subjecting a sulfur source and a dihalo aromatic compound (DHA) to polymerization reaction in an organic amide solvent under alkaline conditions, the method suppressing side reactions or the like and yielding PAS having a high degree of polymerization at a high yield is provided; and PAS having a high degree of polymerization are provided.

A method of producing PAS, including: a preparation step of preparing a preparation mixture containing an organic amide solvent, a sulfur source, an alkali metal hydroxide, water, and DHA, and having a pH of 12.5 or higher; a first-stage polymerization step of heating the preparation mixture to 170° C. or higher to initiate a polymerization reaction and continuing the polymerization reaction at 240 to 280° C., thereby forming a prepolymer having a DHA conversion rate of 50% or greater (at this time, a temperature increasing rate from 220° C. to 240° C. is lower than a temperature increasing rate for 240° C. or higher); and a second-stage polymerization step of adding, in the reaction system, an alkali metal hydroxide in an amount of 1 to 20 mol % per 1 mol of the sulfur source in the presence of a phase separation agent to continue the polymerization reaction at 245 to 290° C. PAS having a melt viscosity (310° C.; shear rate: 1216 sec.sup.-1) of 0.1 to 8000 Pa.Math.s produced by the method.