JP2024022460A - Method for producing polyarylene sulfide resin - Google Patents

Abstract

To provide a method for producing, without increasing steps, a polyarylene sulfide (PAS) resin which suppresses increase in a gas generation amount of when a PAS oligomer is recovered, and is excellent in reactivity to other materials.SOLUTION: There is provided a production method of a PAS resin which includes: a step 1 of reacting a polyhalo aromatic compound with a sulfidizing agent in an organic polar solvent to obtain a crude reaction mixture; a step 2 of adding an acid to the crude reaction mixture; a step 3 of solid-liquid separating the crude reaction mixture by a quench method to obtain a solid-phase component (A); a step 4 of cleaning the solid-phase component (A), removing the alkali metal halide to obtain a solid-phase component (B); and a step 5 of washing the solid-phase component (B) with hot water to obtain a mixture (C) having a pH of 7.0-12.0. The method is characterized in, in addition to comprising the steps, that: the steps 3 to 4 add an oligomer mixture, and the oligomer mixture is an organic polar solvent containing at least a PAS oligomer which is obtained by solid-liquid separation, after a crude reaction mixture is obtained by reacting a polyhalo aromatic compound with a sulfidizing agent in an organic polar solvent.SELECTED DRAWING: None

Description

The present invention relates to a method for producing polyarylene sulfide resin.

Polyarylene sulfide (hereinafter sometimes abbreviated as PAS) resin, represented by polyphenylene sulfide (hereinafter sometimes abbreviated as PPS) resin, has excellent heat resistance, chemical resistance, etc., and is used in electrical and electronic parts, automobile parts, It is widely used for water heater parts, textiles, films, etc.

PPS resin contains almost no reactive sites in its basic skeleton, so while it has excellent chemical resistance, it has poor reactivity when mixed with other materials such as elastomers and silane coupling agents that have reactive functional groups. . When using a PPS resin as a matrix in a resin composition, it is essential to adjust the reactivity of the resin, since the interfacial strength with other materials greatly affects the mechanical properties of the resin composition.

A method for improving the reactivity of PPS resin includes, for example, converting a COONa moiety included as a terminal functional group to COOH (Patent Document 1, etc.). However, since this method also changes the crystallization characteristics of the resin, the shapes that can be suitably used are limited, and there are issues with using this method for parts that take a relatively long time to mold, such as extrusion molded products and large molded products. there were.

Further, the PPS resin can be obtained by a method of polymerizing a sulfidating agent and a polyhaloaromatic compound in a polar organic solvent such as N-methyl-2-pyrrolidone (NMP). At this time, by-products such as PPS oligomers, residual sulfidating agents, and sodium chloride are also produced, but these by-products are considered impurities and have not been utilized in the past. In particular, most of the PPS oligomers were discarded as industrial waste, resulting in a large loss in production in terms of raw material cost loss and disposal cost.

However, when PPS oligomers are recovered into PPS resins, their volatilization temperature is lower than that of resins due to their small molecular weights, and the amount of gas generated during melt-kneading and melt-molding tends to increase. Although it was possible to reduce the amount of gas generated by refining the PPS oligomer in advance, there were problems in cost and environmental impact due to the increase in the number of steps.

Japanese Patent Application Publication No. 2008-247955

Therefore, the problem to be solved by the present invention is to suppress the increase in gas generation when PAS oligomer is recovered without increasing the number of steps, and to provide a PAS resin that has excellent reactivity with other materials. be.

As a result of various studies, the inventors of the present application found that the pH of the resulting mixture was adjusted by adding an acid to the crude reaction mixture of the PAS resin and adding a base in a subsequent specific washing step, and By adding PAS oligomer in a specific process, it is possible to produce PAS resin with excellent reactivity with other materials, and the increase in gas generated due to addition can be suppressed without refining the PAS oligomer in advance. This discovery led to the completion of the present invention.

That is, the present invention allows a polyhaloaromatic compound to react with (i) an alkali metal sulfide, or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide, in an organic polar solvent, Step (1) of obtaining a crude reaction mixture containing at least a PAS resin (a), an alkali metal halide, and an organic polar solvent;
step (2) of adding an acid to the crude reaction mixture;
Step (3) of removing the liquid phase component from the crude reaction mixture by solid-liquid separation using a quench method to obtain a solid phase component (A) containing at least a PAS resin (a) and an alkali metal halide;
a step (4) of washing the solid phase component (A) and removing the alkali metal halide to obtain a solid phase component (B) containing at least the PAS resin (a);
a step (5) of washing the solid phase component (B) with hot water to obtain a mixture (C) having a pH of 7.0 to 12.0, and
In the step (3) to the step (4), adding an oligomer mixture to at least one of the crude reaction mixture, the solid phase component (A), and the solid phase component (B), and
The oligomer mixture is prepared by reacting a polyhaloaromatic compound with (i) an alkali metal sulfide, or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in an organic polar solvent, and at least , PAS resin (b), a PAS oligomer, and an organic polar solvent containing at least a PAS oligomer obtained by removing a solid phase component by solid-liquid separation after obtaining a crude reaction mixture containing a PAS oligomer and an organic polar solvent. The present invention relates to a method for producing a PAS resin characterized by the following.

In the present invention, a polymerization product having 2 to 40 repeating units (dimer to 40mer) may be referred to as an "oligomer."

According to the present invention, it is possible to provide a method for producing a PAS resin that suppresses an increase in the amount of gas generated when PAS oligomers are recovered without increasing the number of steps, and has excellent reactivity with other materials.

Hereinafter, one embodiment of the present invention will be described in detail, but the scope of the present invention is not limited to the one embodiment described here, and various changes can be made without departing from the spirit of the present invention. Additionally, if multiple upper and lower limit values are listed for a specific parameter, any of these upper and lower limit values may be combined to form a suitable numerical range. can.

<Method for manufacturing PAS resin>
The method for producing a PAS resin of the present invention comprises combining a polyhaloaromatic compound and (i) an alkali metal sulfide, or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in an organic polar solvent. A step (1) of reacting to obtain a crude reaction mixture containing at least a PAS resin (a), an alkali metal halide, and an organic polar solvent;
step (2) of adding an acid to the crude reaction mixture;
Step (3) of removing the liquid phase component from the crude reaction mixture by solid-liquid separation using a quench method to obtain a solid phase component (A) containing at least a PAS resin (a) and an alkali metal halide;
a step (4) of washing the solid phase component (A) and removing the alkali metal halide to obtain a solid phase component (B) containing at least the PAS resin (a);
The solid phase component (B) is washed with hot water to obtain a mixture (C) having a pH of 7.0 to 12.0 (5). The details will be explained below.

Process (1)
Step (1) involves reacting a polyhaloaromatic compound with (i) an alkali metal sulfide, or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in an organic polar solvent, This is a step of obtaining a crude reaction mixture containing at least the PAS resin (a), an alkali metal halide, and an organic polar solvent.

Here, in the present invention, the polyhaloaromatic compound is, for example, a halogenated aromatic compound having two or more halogen atoms directly bonded to an aromatic ring, and specifically, p-dichlorobenzene, o -Dichlorobenzene, m-dichlorobenzene, trichlorobenzene, tetrachlorobenzene, dibromobenzene, diiodobenzene, tribromobenzene, dibromnaphthalene, triiodobenzene, dichlorodiphenylbenzene, dibromodiphenylbenzene, dichlor Dihaloaromatic compounds such as benzophenone, dibrombenzophenone, dichlorodiphenyl ether, dibromodiphenyl ether, dichlordiphenyl sulfide, dibromodiphenylsulfide, dichlorbiphenyl, dibrombiphenyl, and mixtures thereof are mentioned, and these compounds can be blocked. May be copolymerized. Among these, preferred are dihalogenated benzenes, and particularly preferred are those containing 80 mol% or more of p-dichlorobenzene. Further, in order to increase the viscosity of the PAS resin by creating a branched structure, a polyhaloaromatic compound having three or more halogen substituents in one molecule may be used as a branching agent as desired. Examples of such polyhaloaromatic compounds include 1,2,4-trichlorobenzene, 1,3,5-trichlorobenzene, and 1,4,6-trichloronaphthalene. Furthermore, polyhaloaromatic compounds having functional groups with active hydrogen such as amino groups, thiol groups, and hydroxyl groups can be mentioned, and specifically, 2,6-dichloroaniline, 2,5-dichloroaniline, etc. , 2,4-dichloroaniline, dihaloanilines such as 2,3-dichloroaniline; 2,3,4-trichloroaniline, 2,3,5-trichloroaniline, 2,4,6-trichloroaniline, 3, Trihaloanilines such as 4,5-trichloroaniline; dihaloaminodiphenyl ethers such as 2,2'-diamino-4,4'-dichlorodiphenyl ether and 2,4'-diamino-2',4-dichlorodiphenyl ether Examples include compounds in which the amino group is replaced with a thiol group or a hydroxyl group in a mixture thereof. In addition, active hydrogen-containing polyhaloaromatic compounds in which the hydrogen atom bonded to the carbon atom forming the aromatic ring in these active hydrogen-containing polyhaloaromatic compounds are substituted with other inert groups, for example, hydrocarbon groups such as alkyl groups. Aromatic compounds can also be used.

Among these various active hydrogen-containing polyhaloaromatic compounds, active hydrogen-containing dihaloaromatic compounds are preferred, and dichloroaniline is particularly preferred.

Examples of polyhaloaromatic compounds having a nitro group include mono- or dihalonitrobenzenes such as 2,4-dinitrochlorobenzene and 2,5-dichloronitrobenzene; 2-nitro-4,4'-dichlorodiphenyl ether, etc. dihalonitrodiphenyl ethers; dihalonitrodiphenyl sulfones such as 3,3'-dinitro-4,4'-dichlorodiphenylsulfone; 2,5-dichloro-3-nitropyridine, 2-chloro-3,5 - Mono- or dihalonitropyridines such as dinitropyridine; or various dihalonitronaphthalenes.

Further, in the present invention, an alkali metal sulfide or an alkali hydrosulfide and an alkali metal hydroxide (hereinafter sometimes referred to as a sulfidating agent) are used as raw materials.

In the present invention, the alkali metal sulfide includes lithium sulfide, sodium sulfide, rubidium sulfide, cesium sulfide, and mixtures thereof. Such alkali metal sulfides can be used as hydrates or aqueous mixtures or as anhydrides. Moreover, an alkali metal sulfide can also be derived by a reaction between an alkali metal hydrosulfide and an alkali metal hydroxide. Note that a small amount of alkali metal hydroxide may be added in order to react with alkali metal hydrosulfide and alkali metal thiosulfate, which are usually present in a small amount in the alkali metal sulfide.

Further, the alkali metal hydrosulfide includes lithium hydrogen sulfide, sodium hydrogen sulfide, rubidium hydrogen sulfide, cesium hydrogen sulfide, and mixtures thereof. Such alkali metal hydrosulfides can be used as hydrates or aqueous mixtures or as anhydrides.

Further, the alkali metal hydrosulfide is used together with an alkali metal hydroxide. Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, etc. Each of these may be used alone, or two or more types may be used in combination. It may also be used as Among these, lithium hydroxide, sodium hydroxide, and potassium hydroxide are preferred because they are easily available, and sodium hydroxide is particularly preferred.

The method for producing PAS resin of the present invention can also use a hydrous sulfidating agent as a raw material. In that case, the PAS resin is It is preferable to subject it to a polymerization reaction. In addition, when the amount of the aprotic polar solvent charged is small, for example, when it is less than 1 mol per 1 mol of sulfur atoms of the sulfidating agent, in the presence of the polyhaloaromatic compound, the water-containing sulfidating agent and the non-protic polar solvent are It is preferable to dehydrate the protic polar solvent.

The dehydration step of the hydrous sulfidating agent is performed by adding at least an aprotic polar solvent and a hydrous alkali metal sulfide or a hydrous alkali hydrosulfide and an alkali metal hydroxide as the hydrous sulfidating agent to a reaction vessel equipped with a distillation apparatus. Water is removed by distillation by heating to a temperature at which water is removed azeotropically, specifically in the range of 300°C or lower, preferably in the range of 80 to 220°C, more preferably in the range of 100 to 200°C. This is done by discharging it out of the system. In the dehydration step, dehydration is performed until the amount of water in the system performing the polymerization reaction becomes 5 mol or less, more preferably in the range of 0.01 to 2.0 mol, per 1 mol of sulfur atoms of the sulfidating agent. It is preferable.

In the present invention, examples of organic polar solvents include formamide, acetamide, N-methylformamide, N,N-dimethylacetamide, tetramethylurea, N-methyl-2-pyrrolidone, 2-pyrrolidone, N-methyl-ε-caprolactam. , ε-caprolactam, hexamethylphosphoramide, N-dimethylpropylene urea, amides such as 1,3-dimethyl-2-imidazolidinonic acid, urea and lactams; sulfolanes such as sulfolane and dimethylsulfolane; benzonitrile, etc. nitriles; ketones such as methylphenylketone and mixtures thereof; among these, N-methyl-2-pyrrolidone, 2-pyrrolidone, N-methyl-ε-caprolactam, ε-caprolactam, hexamethyl Amides having an aliphatic cyclic structure such as phosphoramide, N-dimethylpropylene urea, and 1,3-dimethyl-2-imidazolidinonic acid are preferred, and N-methyl-2-pyrrolidone is more preferred.

The polymerization reaction of the PAS resin in the PAS polymerization step involves reacting the alkali metal sulfide as a sulfidating agent with a polyhaloaromatic compound in the presence of these organic polar solvents. Alternatively, in the polymerization reaction of the PAS resin, the alkali metal hydrosulfide and alkali metal hydroxide as a sulfidizing agent are reacted with a polyhaloaromatic compound in the presence of these organic polar solvents. Polymerization conditions generally range from 200 to 330° C. and pressure should be such as to maintain the polymerization solvent and monomer polyhaloaromatic substantially in the liquid phase, generally 0. The pressure is selected from the range of 1 to 20 MPa, preferably 0.1 to 2 MPa. The amount of the polyhaloaromatic compound charged is in the range of 0.2 mol to 5.0 mol, preferably in the range of 0.8 to 1.3 mol, more preferably in the range of 0.8 to 1.3 mol, per 1 mol of sulfur atom of the sulfidating agent. The amount is adjusted to be in the range of 0.9 to 1.1 mol. Further, the amount of the aprotic polar solvent to be charged is in the range of 1.0 to 6.0 mol, preferably in the range of 2.5 to 4.5 mol, per 1 mol of sulfur atom of the sulfidating agent. adjust. Note that the polymerization reaction is preferably carried out in the presence of a small amount of water, and the ratio is preferably adjusted as appropriate in consideration of the polymerization method, the molecular weight of the resulting polymer, and productivity. Specifically, dehydration is performed so that the amount is 2.0 mol or less, preferably 1.6 mol or less, per 1 mol of sulfur atoms of the sulfidating agent, and further dehydration is performed in the presence of a polyhaloaromatic compound. When performing the operation (for example, the method "5)" in the following specific embodiment), 0.9 mol or less, preferably 0.05 to 0.3 mol, more preferably 0.01 to 0.02 mol or less The dehydration operation may be performed so that the

Specific embodiments of polymerizing the sulfidating agent and the polyhaloaromatic compound in the presence of the aprotic polar solvent described above include, for example,
1) A method using a polymerization aid such as an alkali metal carboxylate or lithium halide;
2) A method using a branching agent such as an aromatic polyhalogen compound,
3) A method of carrying out a polymerization reaction in the presence of a small amount of water, and then adding water and further polymerizing;
4) A method of cooling the gas phase portion of the reaction vessel during the reaction between the alkali metal sulfide and the aromatic dihalogen compound to condense a portion of the gas phase in the reaction vessel and refluxing it to a liquid phase;
5) In the presence of a polyhaloaromatic compound, an alkali metal sulfide, or a hydrous alkali metal hydrosulfide and an alkali metal hydroxide, and an amide, urea or lactam having an aliphatic cyclic structure are reacted while being dehydrated. After producing the slurry, a polar organic solvent such as NMP is further added and water is distilled off to perform dehydration. In the resulting slurry, a polyhaloaromatic compound, an alkali metal hydrosulfide, and an alkali metal salt of the hydrolyzate of an amide, urea, or lactam having an aliphatic cyclic structure are mixed in 1 mol of a polar organic solvent such as NMP. On the other hand, there is a method for producing a PAS resin which has as an essential production step a step of polymerizing the reaction in a state where the amount of water present in the reaction system is 0.02 mol or less.

In this way, by polymerizing the dihalo aromatic compound and the sulfidating agent in an organic polar solvent, a PAS resin is obtained as a product, but in addition to that, a PAS oligomer is also produced as a by-product. Substances contained in the crude reaction mixture may also include by-products such as alkali metal-containing inorganic salts, carboxyalkylamino group-containing compounds, terminal SH group-containing compounds, unreacted raw materials, and water. good.

Process (2)
Step (2) is a step of adding an acid to the crude reaction mixture. By adding an acid in this step and performing subsequent steps, the reactivity, crystallization temperature, alkali metal content, etc. of the resulting PAS resin can be controlled. Examples of the acid used here include hydrochloric acid, sulfuric acid, carbonic acid, acetic acid, oxalic acid, citric acid, etc. Among these, acetic acid, oxalic acid, etc. are preferred.

The amount of acid added in this step is not particularly limited, but for example, preferably 0.2 mol%, particularly preferably 0.5 mol%, and preferably 10.0 mol%, based on 1 mol of the charged alkali metal sulfide. The range is mol % or less, particularly preferably 6.0 mol % or less.

The method of adding the acid to the crude reaction mixture in this step is not particularly limited, but when the acid is liquid, it is added as is or diluted with another solvent, preferably the organic polar solvent used in step (1). When the acid is a solid, it is preferable to dissolve the acid in an appropriate medium such as water or the above-mentioned organic polar solvent, and then add the acid.

The temperature of the acid treatment is not particularly limited, but can preferably be any temperature from room temperature to the polymerization reaction temperature of the PAS resin, particularly preferably from room temperature to 250°C. If the treatment temperature is less than the above lower limit, the effects of the present invention cannot be fully achieved. The acid treatment time varies depending on the treatment temperature, the properties of the PAS resin to be treated, etc., but is preferably 5 minutes to 24 hours, particularly preferably 20 minutes to 3 hours. If the treatment time is less than the above lower limit, the effects of the present invention cannot be sufficiently achieved as described above. Moreover, there is no particular restriction on the pressure, and the treatment is preferably carried out by injecting acid into the reaction vessel after the reaction is completed.

Process (3)
Step (3) is to remove a liquid phase component from the crude reaction mixture that has passed through step (2) through solid-liquid separation using a quench method to obtain a solid phase component (A) containing at least the PAS resin (a) and an alkali metal halide. ). Solid-liquid separation methods can be roughly divided into two types: a flash method and a quench method, which will be described later. However, in the present invention, it is preferable to use the quench method.

The flash method is a method in which the solvent in the crude reaction mixture is evaporated to recover the solvent and solids are recovered at the same time.Generally, the crude reaction mixture is flashed from a high temperature and high pressure state into an atmosphere at normal pressure or reduced pressure. In this method, the solvent is distilled off and recovered, and at the same time, the solid material containing the PAS resin is turned into powder and recovered.

On the other hand, the quench method is a method of gradually cooling the crude reaction mixture to recover particulate PAS resin. Generally, the crude reaction mixture is gradually cooled from a high temperature and high pressure state to recover the PAS resin in the reaction system. This is a method in which the solid content containing the PAS resin is recovered as granules by crystallizing the PAS resin and then performing solid-liquid separation by filtration or the like. There is no particular restriction on the cooling time, but the preferred range is usually 0.1°C/min to 3°C/min. In addition, there is no need to slow-cool at the same rate throughout the slow-cooling process; the speed should be in the range of 0.1°C/min to 1°C/min until the PAS resin granules crystallize, and then 1°C/min thereafter. A method of cooling at a rate of 1 minute or more is also preferable. It is preferable to finally cool the mixture to 70° C. or higher, preferably 100° C. or higher and 200° C. or lower, and then perform solid-liquid separation to recover the solid content containing the PAS resin. Solid-liquid separation in the quench method is performed by separating using filtration or a centrifugal separator such as a screw decanter, then adding water directly to the resulting filtration residue to form a slurry, and then repeating solid-liquid separation, or by repeatedly performing solid-liquid separation. For example, the remaining solvent may be removed by heating the filtration residue under a non-oxidizing atmosphere. The quench method is more preferable in this step because it makes it difficult for impurities such as the by-products and unreacted raw materials to be incorporated into the polymer particles during crystallization, and more PAS oligomers can be recovered.

Process (4)
Step (4) is a step of washing the solid phase component (A) and removing the alkali metal halide to obtain a solid phase component (B) containing at least the PAS resin (a).

In this step, the solid phase component (A) is washed with water. After washing with water, the PAS resin is separated by filtration to perform solid-liquid separation, for example, a reaction slurry obtained by solid-liquid separation of the aprotic polar solvent from the crude reaction mixture obtained in the PAS manufacturing process described below A method in which water is added to the mixture, stirred, and then filtered using a filtration device, and water is added again to the filtration residue containing water obtained by the above-mentioned filtration (hereinafter abbreviated as "water-containing cake") to form a slurry. Examples include a method in which the cake is filtered afterwards, or a method in which water is added again to the water-containing cake while it is held in a filter and the cake is filtered.

During the water washing, the amount of water added to the solid phase component (A) is preferably in the range of 2 to 10 times the theoretical yield of the PAS resin finally obtained, from the viewpoint of washing efficiency. It is preferable to divide the above amount of water into 2 to 10 times, preferably 2 to 4 times, for washing. The washing with water is preferably carried out in a nitrogen or air atmosphere at a water temperature in the range of 20°C to 100°C, and more preferably in the range of 50°C to 100°C in order to improve the washing efficiency. Furthermore, it is most preferable to conduct the reaction at a temperature in the range of 70°C to 90°C. The water washing can be repeated once or multiple times. When water washing is repeated multiple times, the atmosphere and temperature conditions may be the same or different.

Process (5)
Step (5) is a step of washing the solid phase component (B) with hot water to obtain a mixture (C) having a pH of 7.0 to 12.0.

The temperature of hot water washing in this step is preferably in the range of 100 to 280°C, and more preferably in the range of 120 to 275°C, for good extraction efficiency of alkali metal halides and sulfidating agents remaining in the resin. This is preferable from the point of view. More specifically, the extraction treatment can be carried out with hot water at 140 to 260°C under the condition that the pressure of the gas phase in the reactor is increased, preferably 0.2 to 4.6 MPa (gauge pressure). preferable.

A specific method for carrying out such hot water washing includes a method of washing the PAS resin filtered off after the water washing with water in a pressure vessel under stirring under predetermined pressure and temperature conditions. It is preferable that the amount of water during washing with hot water is 1.5 to 10 times the mass of the PAS resin in order to improve the extraction efficiency of the alkali metal halide and sulfidating agent. The hot water washing may be carried out in two or more times. For example, when hot water washing is repeated twice, filtration is performed between the first hot water washing and the second hot water washing, and the alkali metal halide and sulfidating agent extracted in the first hot water washing are combined with the PAS resin. It is preferable to separate by filtration. Alternatively, filtration may be performed after washing with hot water once, and the above-described washing with water may be performed. This operation can also facilitate the separation and removal of the alkali metal halide and sulfidating agent from the PAS resin. Furthermore, the conditions for the first hot water washing step and the second hot water washing step can be arbitrarily selected from the above conditions, but the temperature for the first hot water washing step is, for example, within the range of 120°C to 200°C. After setting and first filtering and removing the highly alkaline filtrate, the temperature of the second hot water washing step is set to a temperature higher than the temperature of the first hot water washing step, for example, a temperature in the range of 150 ° C. to 275 ° C. It is preferable to carry out the hot water washing from the viewpoint of chemical resistance of the equipment used in the hot water washing.

In this process, it is possible to use a washing tank with an agitator and a centrifugal separator for solid-liquid separation, but it is also possible to use a washing tank with an agitator and a centrifugal separator for separating solid and liquid. It can also be carried out in a container with a mixing function. In addition, even for hot water washing exceeding 100°C, it is possible to use a washing tank with a stirrer to perform hot water washing, and a centrifuge for subsequent filtration at 20 to 100°C. It is also possible to conduct the mixing in a closed type container having wings and a filtration filter disposed at the bottom or a container having a mixing function that can be closed. In the present invention, water washing or hot water washing may be carried out continuously or batchwise.

The pH of the mixture (C) after washing with hot water in this step is preferably 7.0 or higher, more preferably 10.0 or higher, and even more preferably 10.5 or higher. Further, it is preferably 12.0 or less, more preferably less than 12.0, and even more preferably 11.5. By adjusting it within this range, impurities contained in the oligomer mixture can be efficiently removed, thereby reducing the amount of gas generated from the resulting resin.

In addition, in this step, the pH can also be adjusted by adding a base to the mixture (B) in advance before washing with hot water. The base that can be used is not particularly limited, but includes, for example, lithium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, rubidium hydroxide, magnesium hydroxide, calcium hydroxide, barium hydroxide, aluminum hydroxide. , metal hydroxides such as iron hydroxide, or lithium carbonate, sodium carbonate, ammonium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium phosphate, calcium phosphate, sodium hypochlorite, potassium hypochlorite, Examples include calcium hypochlorite and sodium acetate, and among these, sodium hydroxide is preferred.

Further, in the method for producing a PAS resin of the present invention, in the step (3) to the step (4), at least one of the crude reaction mixture, the solid phase component (A), and the solid phase component (B) is It is characterized in that an oligomer mixture is added to the mixture. Specifically, the crude reaction mixture before solid-liquid separation in step (3), the solid phase component (A) before washing in step (4), and the solid phase component (B) after washing in step (4) Oligomer mixtures can be added. The oligomer mixture may be added once, or may be added in two or more parts.

The oligomer mixture used in the present invention reacts a polyhaloaromatic compound with (i) an alkali metal sulfide, or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in an organic polar solvent. to obtain a crude reaction mixture containing at least a PAS resin (b), a PAS oligomer, and an organic polar solvent, and then a solid phase component was removed by solid-liquid separation to obtain an organic polar solvent containing at least a PAS oligomer. It is a solvent. The method for obtaining the oligomer mixture is not particularly limited, but includes, for example, a method of solid-liquid separation of the crude reaction mixture obtained by the same method as step (1). The solid-liquid separation method can be performed in the same manner as in step (3).

The amount of the oligomer mixture added is not particularly limited, but it is preferable that the amount of PAS oligomer contained in the oligomer mixture is 10 parts by mass or less with respect to 100 parts by mass of PAS resin (a) contained in the object to be added. When adding the oligomer mixture in multiple portions, the total amount added is preferably 10 parts by mass or less based on 100 parts by mass of the PAS resin (a). Within this range, PAS oligomer can be efficiently recovered into PAS resin while suppressing generated gas.

The filtered PAS resin is collected, and then it can be dried as it is and used as a PAS resin powder, or it can be further washed, separated into solid and liquid, and dried to be used as a powder or granular PAS resin. It can also be prepared. Furthermore, the obtained powdery or granular PAS resin can be heat-treated to form a crosslinked PAS resin.

The specific numerical value of the terminal carboxyl group of the PAS resin (a) contained in the mixture (C) that has undergone the above steps (1) to (5) does not need to be particularly limited, It is preferably in the range of [μmol/g] or less, more preferably in the range of 20 to 50 [μmol/g], and even more preferably in the range of 30 to 40 [μmol/g]. Note that 0 [μmol/g] preferably means that the terminal carboxy group is not contained, but it usually means that it is below the detection limit. This range is preferable because the resulting PAS resin has excellent reactivity.

Furthermore, the specific numerical value of the terminal metal salt of the PAS resin (a) contained in the mixture (C) that has undergone the above steps (1) to (5) does not need to be particularly limited; The range is preferably from 10 to 30 [μmol/g], more preferably from 10 to 30 [μmol/g]. This range is preferable because when melted, the PAS resin and the PAS oligomer tend to undergo an addition reaction to increase the molecular weight of the PAS resin, and the resin composition and molded product obtained after melt processing have excellent impact resistance.

Note that the PAS resin (a) and the PAS resin (b) in this application are different batches of PAS resin. The PAS resin obtained by the production method of the present application contains PAS resin (a) and does not contain PAS resin (b).

The PAS resin obtained through the production method of the present invention described above has the following characteristics.

PAS resins obtained by the above production method tend to have excellent reactivity. Although the specific reactivity is not particularly limited, for example, in PAS resins of the same viscosity, the kneading torque evaluated by the method of the example tends to show a larger value. As another method, for example, the reaction may be determined by the rate of change between the kneading torque value measured using the method of the example and the kneading torque value measured without adding γ-glycidoxypropyltrimethoxysilane. be able to evaluate gender.

As in the past, the PAS resin obtained by the present invention can be blended with fillers and other resins, melt-kneaded, directly or once formed into pellets, and then processed by injection molding, extrusion molding, compression molding, blow molding, etc. By various melt processing methods, it is possible to make molded products with excellent heat resistance, moldability, dimensional stability, etc. However, in order to further improve performance such as strength, heat resistance, and dimensional stability, it is also possible to use it in combination with various fillers as long as the purpose of the present invention is not impaired. Examples of the filler include fibrous fillers and inorganic fillers. In addition, small amounts of mold release agents, colorants, heat stabilizers, ultraviolet stabilizers, foaming agents, rust preventives, flame retardants, lubricants, and cups may be used as additives during molding without departing from the purpose of the present invention. A ring agent can be included. Furthermore, the following synthetic resins and elastomers can be mixed and used in the same manner. These synthetic resins include polyester, polyamide, polyimide, polyetherimide, polycarbonate, polyphenylene ether, polysulfone, polyethersulfone, polyetheretherketone, polyetherketone, polyarylene, polyethylene, polypropylene, polytetrafluoroethylene, Examples of the elastomer include polydifluoroethylene, polystyrene, ABS resin, epoxy resin, silicone resin, phenol resin, urethane resin, and liquid crystal polymer, and examples of the elastomer include polyolefin rubber, fluorine rubber, and silicone rubber.

Molded products obtained by melt-molding the PAS resin of the present invention or a resin composition containing the same have excellent heat resistance and dimensional stability similar to PAS resins obtained by conventional methods.・Electrical/electronic parts such as encapsulated molded products, automotive parts such as lamp reflectors and various electrical components, interior materials for various buildings, aircraft, and automobiles, and precision parts such as OA equipment parts, camera parts, and watch parts. It can be widely used as injection molded or compression molded products such as, or extrusion molded or pultruded products such as fibers, films, sheets, pipes, etc. Furthermore, since the crystallization speed is slower than PPS resin obtained by conventional methods, it is possible to slow down the solidification of the gate part and apply pressure to the thick part during injection molding, which eliminates the lack of filling in the past. This can prevent a decrease in strength. For this reason, it is particularly suitable for large or thick molded products, preferably injection molded products, such as injection molded products with a wall thickness of 4 mm or more, and large injection molded products with a side of 200 mm or more. preferably available.

The present invention will be specifically described below with reference to Examples. These examples are illustrative and not limiting. In addition, hereinafter, unless otherwise specified, "%" and "part" are based on mass.

<Evaluation>

(1) Quantification of metal terminals The PPS resins obtained in Examples 1 to 8 and Comparative Examples 1 to 8 were weighed into a platinum crucible, and concentrated sulfuric acid (atomic absorption grade) was added thereto to the extent that the crucible was submerged. Heated with HP-103K. After confirming that most of the residue had been incinerated and no smoke was coming out of the residue, it was taken out and further heated in a muffle furnace at 700°C for 5 hours to completely incinerate it. After cooling to room temperature, the obtained ash was dissolved in a 1% aqueous hydrochloric acid solution, and the amount of metal in the aqueous solution was measured using an atomic absorption photometer. The amount of metal in the PPS resin was calculated from the obtained value. The water used in this operation had a conductivity of 18.2 MΩ·cm. The measurement results are shown in Tables 1 to 4.

(2) Quantification of terminal carboxyl groups The PPS resins obtained in Examples 1 to 8 and Comparative Examples 1 to 8 were pressed at 350°C and then rapidly cooled to produce a film exhibiting amorphous properties. Measurement was performed using an external spectrometer (hereinafter abbreviated as "FT-IR device"). In the infrared absorption spectrum, the relative intensity of the absorbance at 1705 cm ^-1 to the absorbance at 630.6 cm ^-1 was determined, and the content of carboxy groups in the measurement sample was determined using a calibration curve prepared by a method described separately later. In addition, the content of the carboxyl group is shown by the number of moles in 1 g of the resin mixture, and its unit is expressed in [μmol/g]. A calibration curve was created using the following method. First, a predetermined amount of 4-chlorophenylacetic acid was added to a PPS resin prepared without acid treatment so as to contain carboxylate at the molecular end, and mixed well. A film similar to the above was prepared, and FT-IR Measurements were made with the device. A calibration curve was created by plotting the relative intensity ratio of the absorbance at the two wavelengths against the carboxy group content calculated from the amount of 4-chlorophenylacetic acid added. The measurement results are shown in Tables 1 to 4.

(3) Evaluation of weight loss 4.0000 g of the PPS resins obtained in Examples 1 to 8 and Comparative Examples 1 to 8 were weighed into an aluminum petri dish using a precision balance. After leaving the sample in a dryer set at 150° C. for 1 hour, the Petri dish was taken out, allowed to cool to room temperature, and then weighed. Next, the petri dish was left to stand in a dryer set at 370° C. for 1 hour, then taken out, allowed to cool to room temperature, and then weighed. The weight loss of each sample was calculated using the following formula. The measurement results are shown in Tables 1 to 4.
{(Weighing value after heating at 150°C) - (Weighing value after heating at 370°C)}/(Weighing value after heating at 150°C) x 100

(4) Measurement of melt viscosity (V6) The melt viscosity (V6) of the PPS resins obtained in Examples 1 to 8 and Comparative Examples 1 to 8 was measured using a flow tester (Model CFT-500C) manufactured by Shimadzu Corporation. The measurement was carried out after holding for 6 minutes at a temperature of 300° C., a load of 1.96 MPa, and an orifice having an orifice length to diameter ratio of 10/1. The measurement results are shown in Tables 1 to 4.

(5) Evaluation of reactivity 0.8% (mass ratio of solid content to PPS resin) of γ-glycidoxypropyltrimethoxysilane was added to the PPS resins obtained in Examples 1 to 8 and Comparative Examples 1 to 8. The sample was used to evaluate the reactivity of the resin from the change in torque during melt-kneading. Melt kneading was carried out using a Laboplast Mill (20-200C, R-60 type mixer, manufactured by Toyo Seiki Seisakusho Co., Ltd.).
℃, 40 rpm, 8 minutes, and the torque [kgf·m] at 8 minutes was measured. The measurement results are shown in Tables 1 to 4.

(6) Quantification of PPS oligomer in oligomer mixture 100.0 g of water was added to 10.0 g of the oligomer mixture obtained in Reference Examples 1 and 2, and the mixture was stirred at room temperature to form a water slurry. After solid-liquid separation of the obtained slurry, the solid phase component was washed with water and thoroughly dried to obtain a PPS oligomer. The mass was measured and the content of PPS oligomer in the oligomer mixture was calculated.

<Reference example 1>
19.413 kg (150 mol) of flaky sodium sulfide (60.3% by mass Na ₂ S) and N-methyl-2- 45.0 kg (454 mol) of pyrrolidone (NMP) was charged. The temperature was raised to 209° C. with stirring under a nitrogen stream, and 4.644 kg of water was distilled out (the amount of remaining water was 1.13 mol per 1 mol of sodium sulfide). Thereafter, the autoclave was sealed and cooled to 180° C., and then 21.631 kg (147 mol) of p-dichlorobenzene (hereinafter abbreviated as p-DCB) and 18.0 kg (182 mol) of NMP were charged. It was further cooled, and at a liquid temperature of 150° C., the liquid temperature was pressurized to 0.1 MPa at a gauge pressure using nitrogen gas, and then the temperature was raised to a liquid temperature of 240° C. over 135 minutes and held for 30 minutes. Thereafter, the temperature of the liquid was raised to 250° C. over 40 minutes, and the temperature was maintained for 73 minutes to allow reaction. Thereafter, the autoclave was cooled. The bottom valve of the autoclave was opened at 100° C., and the reaction slurry was transferred to a 150 L plate filter and filtered under pressure at 120° C., 48.0 kg of NMP was added, and the cake was washed and filtered under pressure again. The mass of the recovered NMP filtrate was 80.0 kg and contained 1.09 kg of PPS oligomer. The NMP filtrate was charged into an evaporator with a can wall temperature of 150° C., and NMP was removed by distillation under reduced pressure to obtain 2.02 kg of a PPS oligomer mixture with an oligomer content of 54% by mass.

<Reference example 2>
The same procedure as in Reference Example 1 was carried out except that the NMP filtrate was charged into an evaporator with a can wall temperature of 250° C., and 3.52 kg of a PPS oligomer mixture having an oligomer content of 31% by mass was obtained.

<Example 1>
Process (1)
19.413 kg of flaky sodium sulfide (60.3% by mass Na ₂ S) and 45.0 kg of NMP were charged into a 150 L autoclave equipped with a stirring blade and a bottom valve connected to a pressure gauge, a thermometer, and a condenser. The temperature was raised to 209° C. with stirring under a nitrogen stream, and 4.644 kg of water was distilled out via a condenser (the amount of water remaining in the autoclave was 1.13 mol per mol of sodium sulfide). Thereafter, the autoclave was sealed and cooled to 180° C., and 22.185 kg of p-DCB was dissolved in 18.0 kg of NMP and charged under reduced pressure. The solution was further cooled, and at a liquid temperature of 150° C., nitrogen gas was used to pressurize the solution to a gauge pressure of 0.1 MPa, thereby starting to raise the temperature. The reaction proceeded by stirring for 3 hours while cooling the autoclave at a liquid temperature of 260° C. by sprinkling water on the upper part of the autoclave. Thereafter, when the liquid temperature was lowered, cooling of the upper part of the autoclave was stopped. The maximum pressure during the reaction was 0.85 MPa.

Process (2)
After the reaction, it was cooled, and at a temperature of 170°C, a solution containing 0.471 kg of oxalic acid dihydrate (2.5 mol%, 3.7 mol relative to the sulfidating agent) in 1.099 kg of NMP was injected under pressure. did. After stirring for 30 minutes, the mixture was cooled to 100°C.

Process (3)
The reaction slurry cooled to 100°C was transferred to a 150L flat plate filter and filtered under pressure at 120°C, and then 16 kg of NMP was added and filtered under pressure. After filtration, NMP was removed by stirring under reduced pressure at 150° C. for 2 hours using a 150 L vacuum dryer equipped with stirring blades, to obtain a mixture (A) containing PPS resin.

Process (4)
1000 g of ion-exchanged water at 70° C. was added to 417 g of the mixture (A), stirred for 20 minutes, and then filtered. The same operation was repeated twice to obtain a mixture (B). The obtained mixture (B), 600 g of ion-exchanged water, and 2% by mass of the PPS oligomer mixture produced in Reference Example 1 as a PPS oligomer were added to the PPS resin contained in the mixture (B), and an aqueous sodium hydroxide solution ( 5 g (0.040 mol %, 59 mmol based on the sulfidating agent) of 48% by mass NaOH was charged into a 1 L autoclave equipped with a stirrer.

Process (5)
The charged mixed solution was stirred at 160°C for 3 hours. After cooling to room temperature, it was filtered and the pH of the filtrate was confirmed to be 7.4. 800 g of ion-exchanged water at 70° C. was added to the obtained water-containing cake and filtered. The obtained water-containing cake was dried in a hot air circulation dryer at 120° C. for 6 hours to obtain a white powdery PPS resin.

<Example 2>
The oligomer mixture used in step (4) was the PPS oligomer mixture produced in Reference Example 2, and the amount added was 3% by mass as PPS oligomer based on the PPS resin contained in mixture (B), and an aqueous sodium hydroxide solution ( Same as Example 1 except that 8 g (0.061 mol %, 90 mmol based on the sulfidating agent) of 48 mass% NaOH) and that the pH of the filtrate in step (5) was 7.5. A white powdery PPS resin was obtained.

<Example 3>
The addition amount of the PPS oligomer mixture produced in Reference Example 1 of step (4) was 3% by mass as PPS oligomer with respect to the PPS resin contained in mixture (B), and the sodium hydroxide aqueous solution (48% by mass NaOH) was The same procedure as in Example 1 was carried out except that 10 g (0.080 mol %, 119 mmol based on the sulfidating agent) and the pH of the filtrate in step (5) was 7.9, and a white powder was obtained. A PPS resin was obtained.

<Example 4>
The addition amount of the PPS oligomer mixture produced in Reference Example 1 to the mixture (A) in step (4) was 3% by mass as PPS oligomer to the PPS resin contained in the mixture (A), and an aqueous sodium hydroxide solution. Same as Example 1 except that 67 g (0.541 mol %, 801 mmol of the sulfidating agent) of (48 mass% NaOH) was used, and that the pH of the filtrate in step (5) was 11.2. A white powdery PPS resin was obtained in the same manner.

<Example 5>
The amount of the PPS oligomer mixture produced in Reference Example 1 added to the mixture containing PPS resin after pressure filtration in step (3) was 3% by mass as PPS oligomer based on the PPS resin contained in the mixture; The sodium hydroxide aqueous solution (48 mass% NaOH) in step (4) was 27 g (0.216 mol%, 320 mmol relative to the sulfidating agent), and the pH of the filtrate in step (5) was 10.7. A white powdery PPS resin was obtained in the same manner as in Example 1 except for the following.

<Example 6>
The oligomer mixture used in step (4) was the PPS oligomer mixture produced in Reference Example 2, and the amount added was 5% by mass as PPS oligomer based on the PPS resin contained in mixture (B), and an aqueous sodium hydroxide solution ( Same as Example 1 except that 48% by mass NaOH) was 14g (0.115% by mole, 169 mmol based on the sulfidating agent) and the pH of the filtrate in step (5) was 8.8. A white powdery PPS resin was obtained.

<Example 7>
The amount of the PPS oligomer mixture produced in Reference Example 1 of step (4) was 7% by mass as PPS oligomer with respect to the PPS resin contained in mixture (B), and the sodium hydroxide aqueous solution (48% by mass NaOH) was The same procedure as in Example 1 was carried out except that 19 g (0.153 mol %, 226 mmol based on the sulfidating agent) and that the pH of the filtrate in step (5) was 9.2, and a white powder was obtained. A PPS resin was obtained.

<Example 8>
The addition amount of the PPS oligomer mixture produced in Reference Example 1 of step (4) was 10% by mass as PPS oligomer with respect to the PPS resin contained in mixture (B), and the sodium hydroxide aqueous solution (48% by mass NaOH) was The same procedure as in Example 1 was carried out except that 60 g (0.487 mol %, 721 mmol based on the sulfidating agent) and that the pH of the filtrate in step (5) was 11.0, and a white powder was obtained. A PPS resin was obtained.

<Comparative example 1>
The PPS oligomer mixture of step (4) was not added, the sodium hydroxide aqueous solution (48 mass% NaOH) was 53 g (0.433 mol %, 641 mmol based on the sulfidating agent), and the step (5) A white powdery PPS resin was obtained in the same manner as in Example 1 except that the pH of the filtrate was 11.0.

<Comparative example 2>
The addition amount of the PPS oligomer mixture produced in Reference Example 1 of step (4) was 5% by mass as PPS oligomer with respect to the PPS resin contained in mixture (B), and the sodium hydroxide aqueous solution (48% by mass NaOH) was A white powdery PPS resin composition was obtained in the same manner as in Example 1, except that no addition was made and the pH of the filtrate in step (5) was 6.3.

<Comparative example 3>
The addition amount of the PPS oligomer mixture produced in Reference Example 1 of step (4) was 5% by mass as PPS oligomer with respect to the PPS resin contained in mixture (B), and the sodium hydroxide aqueous solution (48% by mass NaOH) was The same procedure as in Example 1 was carried out except that 334 g (2.705 mol %, 4003 mmol based on the sulfidating agent) and the pH of the filtrate in step (5) was 12.3, and a white powder was obtained. A PPS resin composition was obtained.

<Comparative example 4>
The amount of the PAP oligomer mixture produced in Reference Example 1 of step (4) was 17% by mass as PPS oligomer with respect to the PPS resin contained in mixture (B), and the aqueous sodium hydroxide solution (48% by mass NaOH) was The procedure was carried out in the same manner as in Example 1, except that 33 g (0.271 mol %, 400 mmol based on the sulfidating agent) and that the pH of the filtrate in step (5) was 10.9, and a white powder was obtained. A PPS resin composition was obtained.

<Comparative example 5>
Process (1)
19.413 kg of flaky sodium sulfide (60.3% by mass Na ₂ S) and 45.0 kg of NMP were charged into a 150 L autoclave equipped with a stirring blade and a bottom valve connected to a pressure gauge, a thermometer, and a condenser. The temperature was raised to 209° C. while stirring under a nitrogen stream, and 4.644 kg of water was distilled out (the amount of remaining water was 1.13 mol per mol of sodium sulfide). Thereafter, the autoclave was sealed and cooled to 180°C, and 22.185 kg of p-DCB and 18.0 kg of NMP were charged. At a liquid temperature of 150° C., the pressure was increased to 0.1 MPa using nitrogen gas, and the temperature was increased. The reaction proceeded with stirring at a liquid temperature of 260° C. for 3 hours, and the autoclave was cooled by sprinkling water on the upper part of the autoclave. The maximum pressure during the reaction was 0.85 MPa.

Process (2)
The autoclave was cooled, and at a temperature of 170°C, a mixed solution of 0.471 kg of oxalic acid dihydrate (2.5 mol %, 3.7 mol relative to the sulfidating agent) and 1.099 kg of NMP was injected under pressure. . Thereafter, the mixture was stirred for 30 minutes and then cooled to 100°C.

Process (3)
After the temperature reached 100° C., the bottom valve of the autoclave was opened and the reaction slurry was taken out into a 150 L vacuum stirring dryer equipped with stirring blades under reduced pressure. Subsequently, NMP was sufficiently removed by stirring at 150° C. under reduced pressure for 2 hours to obtain a powdery mixture of PPS resin and salts.

Process (4)
The process of adding 1000 g of ion-exchanged water at 70° C. to 417 g of the mixture, stirring for 20 minutes, and then filtering was repeated twice. The obtained water-containing cake, 600 g of ion-exchanged water, and the PPS oligomer mixture produced in Reference Example 1 were added to the PPS resin in an amount of 5% by mass as PPS oligomer, and 133 g of an aqueous sodium hydroxide solution (48% by mass NaOH) (in relation to the sulfidation agent). (1.082 mol%, 1601 mmol) was charged into a 1 L autoclave equipped with a stirrer.

Process (5)
The charged mixed solution was stirred at 160°C for 30 minutes. After cooling to room temperature, it was filtered and the pH of the filtrate was confirmed to be 11.5. 800 g of ion-exchanged water at 70° C. was added to the obtained water-containing cake and filtered. The obtained water-containing cake was dried in a hot air circulation dryer at 120° C. for 6 hours to obtain a white powdery PPS resin.

<Comparative example 6>
Do not add oxalic acid dihydrate in step (2), do not add PPS oligomer mixture in step (4), and add 4 g of sodium hydroxide aqueous solution (48% by mass NaOH) (0.0% to sulfidating agent). A white powdery PPS resin was obtained in the same manner as in Example 1, except that the pH of the filtrate in step (5) was 10.7.

<Comparative example 7>
Do not add oxalic acid dihydrate in step (2), and add the amount of the PPS oligomer mixture produced in Reference Example 1 in step (4) to 5 mass as PPS oligomer to the PPS resin contained in mixture (B). %, the sodium hydroxide aqueous solution (48 mass% NaOH) was 4 g (0.032 mol %, 48 mmol relative to the sulfidating agent), and the pH of the filtrate in step (5) was 10.9. A white powdery PPS resin was obtained in the same manner as in Example 1 except for the following.

<Comparative example 8>
The PPS oligomer mixture in step (4) was not added, and the sodium hydroxide aqueous solution (48 mass% NaOH) was 89 g (0.725 mol %, 1073 mmol based on the sulfidating agent), and in step (5). The pH of the filtrate is 11.2, and after washing with hot water in step (5), the PPS oligomer mixture produced in Reference Example 1 is added to the filtered water-containing cake as a PAS oligomer for the PPS resin. A white powdery PPS resin composition was obtained in the same manner as in Example 1 except that 800 g of ion-exchanged water at 70° C. was added and filtered after adding 5% by mass.

From the results in Tables 1 to 4, the resins of the examples achieved both highly efficient recovery of PPS oligomers and suppression of the increase in generated gas, and also showed a higher kneading torque value, indicating that they exhibited excellent reactivity. It has been shown.

Claims (2)

At least a polyarylene sulfide resin is produced by reacting a polyhaloaromatic compound with (i) an alkali metal sulfide, or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in an organic polar solvent. (a), step (1) of obtaining a crude reaction mixture containing an alkali metal halide and an organic polar solvent;
step (2) of adding an acid to the crude reaction mixture;
Step (3) of removing a liquid phase component from the crude reaction mixture by solid-liquid separation using a quench method to obtain a solid phase component (A) containing at least a polyarylene sulfide resin (a) and an alkali metal halide;
a step (4) of washing the solid phase component (A) and removing the alkali metal halide to obtain a solid phase component (B) containing at least the polyarylene sulfide resin (a);
a step (5) of washing the solid phase component (B) with hot water to obtain a mixture (C) having a pH of 7.0 to 12.0, and
In the step (3) to the step (4), adding an oligomer mixture to at least one of the crude reaction mixture, the solid phase component (A), and the solid phase component (B), and
The oligomer mixture is prepared by reacting a polyhaloaromatic compound with (i) an alkali metal sulfide, or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in an organic polar solvent, and at least , a crude reaction mixture containing a polyarylene sulfide resin (b), a polyarylene sulfide oligomer, and an organic polar solvent is obtained, and then a solid phase component is removed by solid-liquid separation, and the mixture contains at least a polyarylene sulfide oligomer. A method for producing a polyarylene sulfide resin, characterized by using an organic polar solvent. The method for producing a polyarylene sulfide resin according to claim 1, wherein the polyarylene sulfide oligomer is in a range of 10 parts by mass or less based on 100 parts by mass of the polyarylene sulfide resin (a).