A method is provided for preparing a low temperature thermosetting polyarylene sulfide having significantly low crystallinity while maintaining a low melt flow rate at a high polymerization yield, so as to ensure excellent laser welding property and mechanical properties even when used in a molded product on the transmitting side of laser beam by a laser welding method.

A method is provided for preparing a low temperature thermosetting polyarylene sulfide having significantly low crystallinity while maintaining a low melt flow rate at a high polymerization yield, so as to ensure excellent laser welding property and mechanical properties even when used in a molded product on the transmitting side of laser beam by a laser welding method.

The present invention provides a production method and a production apparatus for a polyarylene sulfide (PAS), thus the formation of a floating polymer and the leakage of the floating polymer to the outside of the vessel in a washing step are prevented, to achieve steady production of the polymer with high quality, to improve the yield of the polymer and to reduce environmental load, wherein the floating polymer refers to a particles of the polymer which are floating on the surface of a washing solution, in the upper part of the inside of a washing vessel, as a result of the adhesion of a gas onto the surface of the particles of the polymer. The present invention provides a production method for a PAS comprising step (I), performing polymerization, step (II), separating and collecting a polymer, step (III), washing a slurry, and step (IV), collecting the polymer after washing, wherein an aqueous medium is sprayed onto a PAS floating on the surface of the aqueous washing solution in the upper part of the inside of the washing vessel in step (III) (step (IIIa), washing a slurry using a counter current, and/or step (IIIb), treating a slurry with acid using a counter current, or the like); and a production apparatus for a PAS comprising a washing device (counter current washing device and/or a counter current contact/acid treatment device or the like) having an aqueous medium spray means.

The present invention provides a production method and a production apparatus for a polyarylene sulfide (PAS), thus the formation of a floating polymer and the leakage of the floating polymer to the outside of the vessel in a washing step are prevented, to achieve steady production of the polymer with high quality, to improve the yield of the polymer and to reduce environmental load, wherein the floating polymer refers to a particles of the polymer which are floating on the surface of a washing solution, in the upper part of the inside of a washing vessel, as a result of the adhesion of a gas onto the surface of the particles of the polymer. The present invention provides a production method for a PAS comprising step (I), performing polymerization, step (II), separating and collecting a polymer, step (III), washing a slurry, and step (IV), collecting the polymer after washing, wherein an aqueous medium is sprayed onto a PAS floating on the surface of the aqueous washing solution in the upper part of the inside of the washing vessel in step (III) (step (IIIa), washing a slurry using a counter current, and/or step (IIIb), treating a slurry with acid using a counter current, or the like); and a production apparatus for a PAS comprising a washing device (counter current washing device and/or a counter current contact/acid treatment device or the like) having an aqueous medium spray means.

Provided is a method of producing polyarylene sulfide (PAS) that suppresses side reactions and produces PAS with a high purity and a high molecular weight at a high yield. A method of producing PAS in which a sulfur source and a dihalo aromatic compound are polymerized in an organic amide solvent, the method of producing PAS comprising the following steps 1 to 3: 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 in an amount that is less than an equimolar amount relative to the sulfur source; step 2: a first-stage polymerization step of initiating a polymerization reaction by heating the mixture, and producing a prepolymer having a dihalo aromatic compound conversion rate of 50% or greater; and step 3: a second-stage polymerization step of adding from 0.11 to 0.3 mol of an alkali metal hydroxide per 1 mol of the sulfur source, and continuing the polymerization reaction. A PAS polymerization reaction solution having a low content of byproduct. PAS having an average particle diameter of 10 to 5,000 m, a melt viscosity (temperature 310 C., shear rate 1,216 sec.sup.1) of 0.1 to 3,000 Pa.Math.s, and a nitrogen content of 750 ppm or less.

Provided is a method of producing polyarylene sulfide (PAS) that suppresses side reactions and produces PAS with a high purity and a high molecular weight at a high yield. A method of producing PAS in which a sulfur source and a dihalo aromatic compound are polymerized in an organic amide solvent, the method of producing PAS comprising the following steps 1 to 3: 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 in an amount that is less than an equimolar amount relative to the sulfur source; step 2: a first-stage polymerization step of initiating a polymerization reaction by heating the mixture, and producing a prepolymer having a dihalo aromatic compound conversion rate of 50% or greater; and step 3: a second-stage polymerization step of adding from 0.11 to 0.3 mol of an alkali metal hydroxide per 1 mol of the sulfur source, and continuing the polymerization reaction. A PAS polymerization reaction solution having a low content of byproduct. PAS having an average particle diameter of 10 to 5,000 m, a melt viscosity (temperature 310 C., shear rate 1,216 sec.sup.1) of 0.1 to 3,000 Pa.Math.s, and a nitrogen content of 750 ppm or less.

A branched polyarylene sulfide resin includes an S substituent group with a cleaved disulfide compound, which has a halogen content of 4,000 ppm or less, a melt viscosity as measured at a temperature of 330 C. and a shear rate of 2 sec.sup.1 of 1.010.sup.4 to 50.0 x 10.sup.4 Pa.Math.s, and a melt viscoelasticity tan as measured at a temperature of 310 C. and an angular velocity of 1 rad/sec of 0.1 to 0.6.

A branched polyarylene sulfide resin includes an S substituent group with a cleaved disulfide compound, which has a halogen content of 4,000 ppm or less, a melt viscosity as measured at a temperature of 330 C. and a shear rate of 2 sec.sup.1 of 1.010.sup.4 to 50.0 x 10.sup.4 Pa.Math.s, and a melt viscoelasticity tan as measured at a temperature of 310 C. and an angular velocity of 1 rad/sec of 0.1 to 0.6.

A method for forming a polyarylene sulfide resin is provided. The method comprises reacting an arylene sulfide polymer containing halogen end groups with an end group-modifying compound to form the polyarylene sulfide resin, wherein the end group-modifying compound includes an organic salt of an aminoalkyl carboxylic acid.

A method for forming a polyarylene sulfide resin is provided. The method comprises reacting an arylene sulfide polymer containing halogen end groups with an end group-modifying compound to form the polyarylene sulfide resin, wherein the end group-modifying compound includes an organic salt of an aminoalkyl carboxylic acid.