Polyarylene sulfide

Abstract

To provide a polyarylene sulfide capable of increasing the melt viscosity of polyarylene sulfide without introducing a branched structure into the polyarylene sulfide molecule by blending the polyarylene sulfide with a conventionally known polyarylene sulfide.　A polyarylene sulfide according to the present invention has one epoxy group per molecule and satisfies formula (I): 1000×(Ha+Hb / 2) / (Hs / 3)≥0.5 …(I) when a mixture of an extract of the polyarylene sulfide obtained by Soxhlet extraction using chloroform, 1,3,5-trimethoxybenzene, and deuterated chloroform is measured by 1H-NMR standardized so that a resonance peak based on chloroform in deuterated chloroform is 7.26 ppm and the integrated values of peaks observed within a predetermined range are taken as Hs, Ha, and Hb.

Description

Polyarylene sulfide

[0001] This invention relates to polyarylene sulfide.

[0002] Polyarylene sulfides (hereinafter also referred to as "PAS"), typified by polyphenylene sulfide (hereinafter also referred to as "PPS"), are engineering plastics with excellent heat resistance, chemical resistance, flame retardancy, mechanical strength, electrical properties, and dimensional stability. PAS can be molded into various molded products, films, sheets, fibers, etc., by common melting processes such as extrusion molding, injection molding, and compression molding. For this reason, PAS is widely used in a wide range of technological fields, including electrical equipment, electronic equipment, automotive equipment, and packaging materials.

[0003] However, PAS has a problem in that it is prone to burr formation during molding due to its low melt viscosity. For this reason, it has been proposed to mix in an aminosilane coupling agent to prevent burr formation (see Patent Documents 1 and 2). As for PAS, PAS having amino groups or carboxyl groups as terminal groups is known. When such terminal groups react with a silane coupling agent such as an aminosilane coupling agent, the PAS becomes more viscous in the molten state.

[0004] Japanese Patent Publication No. 08-053592 Japanese Patent Publication No. 2004-244619

[0005] PAS is widely used, particularly in the automotive sector, as a metal substitute material aimed at reducing the weight of automobiles. When using PAS in automotive applications, high toughness is required. PAS is often molded by injection molding. PAS used in injection molding is required to exhibit high melt viscosity. Generally, cross-linked PAS exhibits higher melt viscosity than linear PAS. However, cross-linked PAS has a branched structure and therefore has lower toughness than linear PAS. Although a method of increasing the viscosity of linear PAS using a silane coupling agent is known, this method also introduces a branched structure into the PAS molecular chain, thus reducing toughness. In light of the above circumstances, there is a need for an additive that can increase the melt viscosity of PAS without introducing a branched structure into the PAS.

[0006] The present invention has been made in view of the above problems, and aims to provide a polyarylene sulfide that, when blended with a polyarylene sulfide produced by a conventional method, can increase the melt viscosity of the polyarylene sulfide without introducing a branched structure into the polyarylene sulfide molecule.

[0007] The present inventors have found that the above objective can be achieved by using a polyarylene sulfide having one epoxy group, wherein when 3.0 mg of the extract obtained by Soxhlet extraction of the polyarylene sulfide is measured under predetermined conditions, the polyarylene sulfide satisfies a predetermined inequality (I), and thus completed the present invention. Specifically, the present invention is configured as follows: [1] to [7].

[0008] [1] A polyarylene sulfide having one epoxy group in its molecule, a mixture of 3.0 mg of an extract of the polyarylene sulfide obtained by Soxhlet extraction using chloroform, 5.0 mg of 1,3,5-trimethoxybenzene, and 0.7 mL of deuterated chloroform, normalized so that the resonance peak based on chloroform in the deuterated chloroform is 7.26 ppm. １ Polyarylene sulfide satisfying the following equation (I): 1000 × (Ha + Hb / 2) / (Hs / 3) ≥ 0.5 ... (I), where Hs is the integral of the peak observed in the range of 6.03 to 6.15 ppm by 1H-NMR, Ha is the integral of the peak observed in the range of 4.58 to 4.89 ppm, and Hb is the integral of the peak observed in the range of 4.00 to 4.25 ppm.

[0009] [2] The polyarylene sulfide according to [1], wherein the Hb and Hs satisfy the following formula (IV): 1000 × (Hb / 2) / (Hs / 3) < 0.2 ... (IV).

[0010] [3] A method for producing polyarylene sulfide, comprising: a mixing step of mixing untreated polyarylene sulfide with a compound containing a bifunctional epoxy group; and a reaction step of reacting the mixture obtained in the mixing step at a temperature of 30°C or higher and 230°C or lower under substantially solvent-free conditions, wherein the untreated polyarylene sulfide has a specific surface area of ​​5 m² measured by the BET method (single-point method) using a mixed gas of nitrogen and helium (nitrogen:helium = 30:70 (volume ratio)) as the adsorption gas. ２ The value is greater than or equal to / g, at a temperature of 310°C and a shear rate of 1200 sec. －１ A method for producing polyarylene sulfide, wherein the melt viscosity measured under the following conditions is 1 Pa·s or more, the amount of functional groups that react with epoxy groups is 14 μmol / g or more, and the sodium content is 800 ppm by mass or less.

[0011] [4] The method for producing polyarylene sulfide according to [3], wherein the heating time in the reaction step is 30 minutes or more and 24 hours or less.

[0012] [5] The method for producing polyarylene sulfide according to [3] or [4], wherein the amount of functional groups that react with the epoxy groups of the untreated polyarylene sulfide is the nitrogen atom content.

[0013] [6] A method for producing polyarylene sulfide according to any one of [3] to [5], further comprising a step of washing the untreated polyarylene sulfide at a temperature below the glass transition temperature and / or drying it before the mixing step.

[0014] [7] The method for producing polyarylene sulfide according to any one of [3] to [6], wherein the amount of the bifunctional epoxy group-containing compound in the mixing step is 70 molar times or more relative to the nitrogen atom content of the untreated polyarylene sulfide.

[0015] According to the present invention, it is possible to provide a polyarylene sulfide that, when incorporated into a polyarylene sulfide produced by a conventional method, can increase the melt viscosity of the polyarylene sulfide without introducing a branched structure into the polyarylene sulfide molecule.

[0016] Hereinafter, embodiments of the present invention will be described in detail. The present invention is not limited to the following embodiments, and appropriate modifications can be made without departing from the gist of the present invention.

[0017] In the present specification, a numerical range represented by using "~" means a range including the numerical values described before and after "~" as the lower limit and the upper limit, and "A to B" refers to a range from A to B (inclusive of both endpoints). In addition, unless otherwise specified in the present specification, "room temperature" refers to 20°C or higher and 25°C or lower, and "melt viscosity" refers to a measurement performed at a temperature of 310°C and a shear rate of 1200 sec －１ -1, and "under reduced pressure conditions" refers to an absolute pressure of 10 Torr or less

[0018] The polyarylene sulfide according to the present invention is described below. The polyarylene sulfide according to the present invention is a polyarylene sulfide that has one epoxy group in the molecule and satisfies the above formula (I) (hereinafter, also referred to as "PAS (A)").

[0019] PAS (A) has a repeating unit of -(Ar-S)- as the main structural component, which is a structure in which an arylene group (hereinafter, also referred to as "Ar") is bonded to a sulfide. Examples of Ar include p-phenylene group, m-phenylene group, o-phenylene group, substituted phenylene group, p,p'-diphenylene sulfone group, p,p'-biphenylene group, p,p'-diphenylene ether group, and naphthalene group.

[0020] PAS (A) can be a homopolymer containing any one of the above repeating units alone, or a copolymer containing two or more of the above repeating units. As the homopolymer, polyphenylene sulfide in which Ar has a p-phenylene group is preferable.

[0021] In PAS(A), Ar is preferably at least 50% by weight of any group selected from the group consisting of p-phenylene group, m-phenylene group, and o-phenylene group, more preferably at least 80% by weight of p-phenylene group, further preferably at least 90% by weight, and particularly preferably at least 98% by weight. Such a structure is preferable in terms of heat resistance and crystallinity.

[0022] <Method for producing PAS(A)> The method for producing the above PAS(A) is not particularly limited. One example of a preferable method for producing PAS(A) is a method comprising reacting an untreated polyarylene sulfide (hereinafter also referred to as "untreated PAS") having predetermined characteristics, which is obtained by polymerizing a sulfur source and a dihaloaromatic compound in N-methyl-2-pyrrolidone (hereinafter also referred to as "NMP") according to a known method, with a bifunctional epoxy group-containing compound.

[0023] PAS(A) produced by the above method has one epoxy group in the molecule. As a result, when PAS(A) is blended into a polyarylene sulfide produced by a conventional method (hereinafter also referred to as "conventionally known PAS"), the epoxy group of PAS(A) favorably reacts with a functional group capable of reacting with an epoxy group that is present at the molecular chain end of the conventionally known PAS, and thus the melt viscosity of the conventionally known PAS can be increased without introducing a branched structure into the same. In the present specification, "conventionally known PAS" and "untreated PAS" are distinguished. Untreated PAS is a PAS having the characteristics described below among conventionally known PAS, and refers to PAS that serves as a raw material for PAS(A).

[0024] (Untreated PAS) First, untreated PAS will be described. The untreated PAS has a specific surface area of 5 m ２ / g or more as measured by the BET method (single-point method) using a mixed gas of nitrogen and helium (nitrogen:helium = 30:70 (volume ratio)) as the adsorption gas, has a melt viscosity of 1 Pa·s or more, an amount of functional groups that react with epoxy groups of 14 µmol / g or more, and a sodium content of 800 ppm by mass or less, and can be used without particular limitation.

[0025] The specific surface area of the untreated PAS is 5 m ２ / g or more, preferably 10 m ２ / g or more and 120 m ２ / g or less, more preferably 15 m ２ / g or more and 120 m ２ / g or less, still more preferably 20 m ２ / g or more and 100 m ２ / g or less, particularly preferably 30 m ２ / g or more and 100 m ２ / g or less. When falling within the above numerical range, a good reaction can be achieved between the untreated PAS and the bifunctional epoxy group-containing compound under temperature conditions where the untreated PAS does not dissolve or melt. To obtain such a specific surface area, the product can be obtained by performing, in the production of untreated PAS, a method (quenching method) of collecting the mixture in which PAS after the polymerization reaction is dissolved by slow cooling and crystallization, or a method (flash method) of collecting the reaction mixture by volatilizing the solvent from the reaction mixture at high temperature. In the present specification, the term "specific surface area" refers to a value measured in accordance with ISO 9277 by the BET method (single-point method) using a mixed gas consisting of nitrogen and helium (nitrogen:helium = 30:70 by volume) as the adsorption gas.

[0026] The melt viscosity of the untreated PAS is 1 Pa·s or more, preferably 5 Pa·s or more and 250 Pa·s or less, more preferably 15 Pa·s or more and 250 Pa·s or less, still more preferably 20 Pa·s or more and 200 Pa·s or less, and particularly preferably 20 Pa·s or more and 150 Pa·s or less. Falling within the above numerical range distinguishes the PAS from PAS mainly composed of low-molecular components such as oligomers.

[0027] Examples of functional groups that react with epoxy groups (hereinafter also referred to as "epoxy-reactive functional groups") include phenolic hydroxyl groups, mercapto groups, and MABA terminal groups. The epoxy-reactive functional group is preferably a MABA terminal group from the viewpoint that it can be easily introduced into untreated PAS by using NMP as a polymerization solvent.

[0028] The aforementioned "MABA-terminated group" is derived from the "-NCH" group, a by-product produced when NMP undergoes ring-opening during polymerization, and is contained in untreated PAS manufactured using NMP as a solvent. ３ -CH ２ CH ２ CH ２ This refers to the terminal group represented as "-COOH".

[0029] The amount of epoxy-reactive functional groups is 14 μmol / g or more, preferably 18 μmol / g to 93 μmol / g, and more preferably 36 μmol / g to 93 μmol / g. Within this range, the untreated PAS and the bifunctional epoxy group-containing compound can react well, and epoxy groups can be introduced into the PAS.

[0030] The amounts of phenolic hydroxyl groups and mercapto groups can be measured, for example, by the purge-trap method. Since the amount of MABA terminal groups is the same as the nitrogen atom content of PAS, the nitrogen atom content can be treated as the amount of MABA terminal groups. In other words, the nitrogen atom content and its preferred range correspond to the amount of epoxy-reactive functional groups and its preferred range described above. The nitrogen atom content is measured using the trace nitrogen analyzer described in the examples. The unit of the nitrogen atom content obtained by this method is mass ppm, but this value can be converted to the amount of substance per gram of PAS (μmol / g) by dividing it by the atomic weight of nitrogen (14.00).

[0031] In the method for producing untreated PAS, the amount of MABA terminal groups can be adjusted by performing polymerization under conditions where a sulfur source and dihalo-aromatic compounds are at high concentrations, or by adjusting the amount of alkali metal hydroxide added.

[0032] The sodium content of untreated PAS (hereinafter also referred to as "Na content") is 800 ppm by mass or less, preferably greater than 0 ppm by mass and 800 ppm by mass or less, more preferably greater than 0 ppm by mass and 500 ppm by mass or less, and even more preferably greater than 0 ppm by mass and 200 ppm by mass or less. The Na content is measured by ICP emission spectroscopy using an ICP-AES (for example, Hitachi High-Tech Corporation's ICP emission spectrometer "SPS3500DD") on a sulfuric acid-decomposed sample, as described in the examples. The Na content of untreated PAS can be adjusted by washing the untreated PAS, and within the above-mentioned range, it can react well with difunctional epoxy group-containing compounds.

[0033] (Method for producing untreated PAS) Untreated PAS as described above can be obtained by a general manufacturing method comprising a preparation step of preparing a preparation mixture containing NMP, a sulfur source, and a dihalo-aromatic compound, and a polymerization step of heating the mixture to carry out a polymerization reaction (see, for example, Japanese Patent Publication No. 61-7332, Japanese Patent Publication No. 9-286861, etc.). In addition to the preparation step and polymerization step described above, the method may also include a dehydration step to reduce the amount of water in the mixture, a post-treatment step, a pre-polymerization step to generate a PAS prepolymer, a phase separation step to add a phase separation agent to the mixture to form a phase-separated state, and a post-polymerization step to carry out a further polymerization reaction after phase separation.

[0034] (Sulfur source and dihalo-aromatic compound) The sulfur source and dihalo-aromatic compound are not particularly limited, and those commonly used in the production of PAS can be used. Each of the sulfur source and the dihalo-aromatic compound may be used alone, or two or more may be used in combination, provided that it is possible to produce a PAS having the desired chemical structure. In this specification and in the claims, "dihalo-aromatic compound" means an aromatic compound in which two hydrogen atoms directly attached to the aromatic ring are replaced by halogen atoms.

[0035] Examples of sulfur sources include alkali metal sulfides, alkali metal hydrosulfides, and hydrogen sulfide, with alkali metal sulfides and alkali metal hydrosulfides being preferred, and alkali metal hydrosulfides being more preferred. The sulfur source can be handled in either the form of an aqueous slurry or an aqueous solution, and from the viewpoint of handling, such as metering and transportability, it is preferable to be in the form of an aqueous solution. Examples of alkali metal sulfides include lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, and cesium sulfide. Examples of alkali metal hydrosulfides include lithium hydrosulfide, sodium hydrosulfide, potassium hydrosulfide, rubidium hydrosulfide, and cesium hydrosulfide.

[0036] Examples of dihaloaromatic compounds include o-dihalobenzene, m-dihalobenzene, p-dihalobenzene, dihalotoluene, dihalonaphthalene, methoxy-dihalobenzene, dihalobiphenyl, dihalobenzoic acid, dihalodiphenyl ether, dihalodiphenyl sulfone, dihalodiphenyl sulfoxide, and dihalodiphenyl ketone. The halogen atoms refer to fluorine, chlorine, bromine, and iodine atoms, and two or more halogen atoms in a dihaloaromatic compound may be the same or different. Among these, p-dihalobenzene, m-dihalobenzene, and mixtures thereof are preferred in terms of availability and reactivity, with p-dihalobenzene being more preferred, and p-dichlorobenzene (hereinafter also referred to as "pDCB") being particularly preferred.

[0037] The amount of dihalo-aromatic compound used is preferably 0.90 moles to 1.50 moles, and more preferably 0.92 moles to 1.10 moles, per mole of sulfur source. When the amount used is within the above range, it is easy to generate high molecular weight polymers, and thus an untreated PAS with high melt viscosity can be obtained.

[0038] (NMP) From the viewpoint of the efficiency of the polymerization reaction, the amount of NMP used is preferably 1 mole to 30 moles, and more preferably 3 moles to 15 moles, per mole of sulfur source charged.

[0039] The sulfur source described above may be mixed with NMP and subjected to the dehydration process.

[0040] (Dehydration Process) The dehydration process is a process performed before the charging process in which at least a portion of the water-containing distillate is discharged from the system containing a mixture of NMP and a sulfur source. The mixture subjected to the dehydration process may optionally contain alkali metal hydroxides. The water to be dehydrated in the dehydration process includes water contained in each raw material charged in the dehydration process, the aqueous medium of the aqueous mixture, and water produced as a by-product of the reaction between the raw materials.

[0041] The heating temperature in the dehydration step is not particularly limited, but is preferably 300°C or lower, and more preferably 100°C to 250°C. It is desirable to dehydrate the mixture until the amount of water in the preparation mixture (described later) is 0.5 moles or more and 2.4 moles or less per 1.0 mole of the amount of sulfur source in the preparation mixture (hereinafter also referred to as "preparation sulfur source"). If the amount of water becomes too low in the dehydration step, water can be added in the preparation step preceding the polymerization step to adjust it to the desired amount of water.

[0042] (Preparation Process) The preparation process is the process of preparing a mixture containing NMP, a sulfur source, and a dihalo-aromatic compound. The mixture prepared in the preparation process is also called the "preparation mixture."

[0043] When a dehydration process is performed, the sulfur source used in the brewing process can be calculated by subtracting the amount of hydrogen sulfide volatilized during the dehydration process from the amount of sulfur source added as a raw material.

[0044] When a dehydration process is performed, alkali metal hydroxides and water may be added to the mixture remaining in the system after the dehydration process during the preparation process, as needed. Examples of alkali metal hydroxides include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, and cesium hydroxide, and those commonly used in the production of PAS can be used. Alkali metal hydroxides may be used individually or in mixtures of two or more types.

[0045] The number of moles of alkali metal hydroxide is calculated based on the number of moles of alkali metal hydroxide added as needed during the initial stage, and, if a dehydration stage is performed, the number of moles of alkali metal hydroxide added as needed during the dehydration stage, as well as the number of moles of alkali metal hydroxide generated in conjunction with the generation of hydrogen sulfide during the dehydration stage. The nitrogen atom content of untreated PAS can be adjusted by adjusting the amount of alkali metal hydroxide in the initial mixture. If the sulfur source contains alkali metal sulfides, the number of moles of alkali metal hydroxide per mole of sulfur source in the initial mixture shall be calculated including the number of moles of alkali metal sulfides.

[0046] In the fermentation mixture, the amounts of NMP and dihalo-aromatic compounds used are set, for example, within the ranges indicated above for NMP and dihalo-aromatic compounds per mole of fermentation sulfur source.

[0047] (Polymerization Process) The polymerization process is a process in which the preparation mixture is heated to initiate the polymerization reaction and produce PAS. From the viewpoint of the efficiency of the polymerization reaction, the polymerization temperature is preferably 170°C to 300°C, and more preferably 180°C to 290°C. The temperature may be maintained at a constant level, or it may be raised or lowered in stages or continuously as needed. In order to obtain high molecular weight PAS, the polymerization reaction may be carried out in two or more stages. For example, when a phase separation agent described later is added during polymerization, the process is carried out in two or more stages, and the process of producing a prepolymer before the addition of the phase separation agent is called the pre-polymerization process, and the process of continuing the polymerization reaction after the addition of the phase separation agent is called the post-polymerization process. The mixture heated in the polymerization process is called the "reaction mixture".

[0048] The conversion rate of the dihalo-aromatic compound at the end of the preceding polymerization step is preferably 60 mol% to 98 mol%, more preferably 65 mol% to 98 mol%. The conversion rate of the dihalo-aromatic compound can be calculated by determining the amount of dihalo-aromatic compound remaining in the reaction mixture by gas chromatography, and then calculating the amount of dihalo-aromatic compound and sulfur source added.

[0049] (Phase Separation Step) The phase separation step is the step of adding a phase separation agent to the starting mixture and / or reaction mixture. The phase separation agent can be one that is normally used in the production of PAS. Examples include water, metal carboxylates, metal sulfonic acid salts, alkali metal halides, etc. Among these, water and / or metal carboxylates are preferred, and water is more preferred. The amount of phase separation agent used varies depending on the type of compound used, but is preferably in the range of 0.01 moles to 20 moles per 1 kg of NMP, and when water is used as the phase separation agent, it is preferably 2 moles to 7 moles.

[0050] There is no specific timing for adding the phase separation agent; it may be added during the preparation process, at the start of polymerization, or in the middle of the polymerization process, with addition in the middle of the polymerization process being preferable. The presence of the phase separation agent allows the polymerization reaction to proceed in a phase-separated state. When the phase separation process is performed in the middle of the polymerization reaction, a state with a high concentration of prepolymer can be formed by liquid-liquid phase separation. This binds the prepolymers together, further growing the chains and yielding a high molecular weight polymer. Furthermore, when the phase separation agent is added in the middle of the polymerization process, the specific surface area of ​​the untreated PAS can be increased by reducing the amount of phase separation agent used within a range where phase separation is possible.

[0051] (Post-treatment and recovery steps) The untreated PAS produced by the method described above may be recovered through post-treatment and recovery steps. The post-treatment and recovery steps can be carried out by conventional methods. For example, by cooling the reaction mixture, a slurry containing granular polymer products can be obtained. The untreated PAS can be recovered by filtering the cooled product slurry as is, or after diluting it with water, and then repeatedly filtering, washing, and filtering it to dry it. Drying is preferably carried out under reduced pressure.

[0052] By generating granular untreated PAS using the method described above, the granular untreated PAS can be separated from the reaction solution and recovered by, for example, sieving it using a 100-mesh screen (mesh opening diameter 150 μm). This allows for easy separation of the untreated PAS from by-products and oligomers.

[0053] Suitable washing solvents for untreated PAS include organic solvents such as NMP, ketones (e.g., acetone), alcohols (e.g., methanol), and water. Granular untreated PAS can also be treated with an aqueous solution containing an acidic compound or a salt such as ammonium chloride. It is preferable to use hot water (e.g., 170°C or higher) and / or an acidic aqueous solution as the washing solvent, and more preferably an acidic aqueous solution. In the polymerization of untreated PAS, sodium salts such as sodium chloride are produced as by-products, and may exist as "-COONa" where the hydrogen of the carboxyl group in the MABA terminal group is replaced by sodium. By treating untreated PAS with hot water and / or an acidic aqueous solution, the Na content is reduced, that is, the carboxyl group in the MABA terminal group can be acidified (-COOH), which facilitates the reaction with difunctional epoxy group-containing compounds, especially alicyclic epoxy group-containing compounds.

[0054] Here, when a washing step (hereinafter also referred to as the "washing step" or "washing") and / or drying step (hereinafter also referred to as the "drying step" or "drying") of the untreated PAS is performed, it is preferable that the temperature during washing and / or drying is below the glass transition temperature of the untreated PAS (for example, 93°C or below). By using such temperature conditions, the end groups of the untreated PAS remain on the outer surface of the PAS particles and become end groups with high reaction activity.

[0055] Although the detailed mechanism is not clear, it is thought to be as follows: In organic polar solvents, particularly in NMP, the affinity between the organic polar solvent and the terminal functional groups in untreated PAS is high. Therefore, even if PAS is heated above the glass transition temperature (hereinafter also referred to as "Tg"), where molecular motion is active, the terminal functional groups of the untreated PAS remain on the solvent side, i.e., the outer surface of the PAS. On the other hand, if the process involves contact with water or air, which has low affinity to the terminal functional groups, the terminal functional groups may fold or burrow into the interior of the PAS, which has a higher affinity than water or air. Therefore, it is desirable to process at a temperature where molecular motion is not active. In the case of PPS, a temperature of 93°C or lower, which is below Tg, is preferred, and a temperature of 20°C to 93°C is more preferred. Furthermore, even when washing and drying are performed under temperature conditions higher than Tg, the reaction-active terminal groups described above can be obtained by heating the untreated PAS in an organic polar solvent at a temperature above the Tg of the untreated PAS but below the temperature at which the untreated PAS does not melt (for example, 95°C to 230°C), and drying it at a temperature below the Tg of the PAS. However, as described later, there is a risk that the amount of PAS containing MABA terminal groups will decrease, so it is preferable to wash and dry the untreated PAS at a temperature below Tg.

[0056] The organic polar solvent is not particularly limited as long as it is a solvent commonly used in PAS production, but organic amide solvents having an amide bond in their molecular structure are preferred, and amide compounds having an aliphatic cyclic structure such as N-methyl-ε-caprolactam, NMP, and N-cyclohexyl-2-pyrrolidone are more preferred, with NMP being particularly preferred.

[0057] By using reactive terminal groups, untreated PAS and a bifunctional epoxy group-containing compound can be reacted well even under temperature conditions where the untreated PAS does not melt or dissolve, and under substantially solvent-free conditions. The Tg of PAS can be measured by known methods, for example, using a differential scanning calorimeter (DSC) in accordance with ISO 11357-2 (2020).

[0058] By the method described above, untreated PAS, which is the raw material for PAS(A), can be obtained.

[0059] (Method for producing PAS(A)) PAS(A) can be obtained by reacting the untreated PAS obtained as described above with a compound containing a bifunctional epoxy group.

[0060] A method for producing PAS(A) includes a mixing step of mixing untreated PAS with a bifunctional epoxy group-containing compound, and a reaction step of reacting the mixture obtained in the mixing step at a temperature of 30°C to 230°C under substantially solvent-free conditions. In addition to the above steps, the method may also include a step of washing and / or drying the untreated PAS as described above, and a step of washing and / or drying the PAS(A).

[0061] A difunctional epoxy group-containing compound is a compound having two epoxy groups in one molecule. It is not particularly limited as long as it is a difunctional epoxy group-containing compound. The difunctional epoxy group-containing compound may be a glycidyl group-containing compound, or an alicyclic epoxy group-containing compound having an epoxy group composed of two adjacent carbon atoms and an oxygen atom constituting an alicyclic structure such as an epoxycycloalkyl group; alicyclic epoxy group-containing compounds are preferred. Using an alicyclic epoxy group-containing compound allows for better reaction with untreated PAS with reduced Na content. This allows for the introduction of more epoxy groups at the ends of PAS(A), thus increasing the melt viscosity of polyarylene sulfide when compounded with conventionally known PAS.

[0062] Suitable examples of glycidyl group-containing compounds as difunctional epoxy group-containing compounds include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD ​​type epoxy resin, naphthalene type epoxy resin, and biphenyl type epoxy resin.

[0063] A suitable example of a alicyclic epoxy group-containing compound having an alicyclic epoxy group such as an epoxycycloalkyl group, as a bifunctional epoxy group-containing compound, is the compound represented by the following formula (i).

[0064] In formula (i) above, X represents a single bond or a linking group. Preferred examples of linking groups include one or more selected from the group consisting of a divalent hydrocarbon group, an alkenylene group in which the carbon-carbon double bond is epoxidized (hereinafter also referred to as "epoxidized alkenylene group"), a carbonyl group, an ether bond, a carboxylic acid ester bond, a siloxane bond, a carbonate group, and a carboxylic acid amide group. Note that substituents such as alkyl groups may be attached to the cyclohexene oxide group in formula (i).

[0065] Examples of divalent hydrocarbon groups include linear or branched alkylene groups having 1 to 18 carbon atoms, and divalent alicyclic hydrocarbon groups.

[0066] Examples of linear or branched alkylene groups having 1 to 18 carbon atoms include the methylene group, methylmethylene group (ethane-1,1-diyl group), dimethylmethylene group (propane-2,2-diyl group), ethylene group, propylene group, and trimethylene group.

[0067] Examples of divalent alicyclic hydrocarbon groups include cycloalkylene groups such as 1,2-cyclopentylene, 1,3-cyclopentylene, cyclopentylidene, 1,2-cyclohexylene, 1,3-cyclohexylene, 1,4-cyclohexylene, and cyclohexylidene, or cycloalkylidene groups.

[0068] Examples of alkenylene groups in epoxidized alkenylene groups include linear or branched alkenylene groups having 2 to 8 carbon atoms, such as vinylene group (ethylene-1,2-diyl group), 1-propene-1,3-diyl group, 1-propene-1,2-diyl group, 1-propene-2,3-diyl group, 1-butene-1,4-diyl group, 1-butene-1,3-diyl group, 1-butene-1,2-diyl group, 2-butene-1,4-diyl group, 2-butene-1,3-diyl group, 2-butene-1,2-diyl group, 1-pentene-1,5-diyl group, 1-hexene-1,6-diyl group, 1-heptene-1,7-diyl group, and 1-octene-1,8-diyl group. The epoxidized alkenylene group is preferably an alkenylene group having 2 to 4 carbon atoms in which the carbon-carbon double bond is epoxidized.

[0069] Examples of compounds represented by formula (i) include (3,4,3',4'-diepoxy)bicyclohexyl, bis(3,4-epoxycyclohexylmethyl) ether, 1,2-epoxy-1,2-bis(3,4-epoxycyclohexane-1-yl)ethane, 2,2-bis(3,4-epoxycyclohexane-1-yl)propane, 1,2-bis(3,4-epoxycyclohexane-1-yl)ethane, and compounds represented by the following formulas (i-1) to (i-9). In the following formulas (i-5) and (i-7), l and m represent integers from 1 to 30, respectively. In the following formula (i-5), R' is an alkylene group having 1 to 8 carbon atoms, and linear or branched alkylene groups having 1 to 3 carbon atoms, such as a methylene group, an ethylene group, a propane-1,3-diyl group, and a propane-1,2-diyl group, are preferred.

[0070]

[0071] Examples of compounds having an alicyclic epoxy group include, in addition to the compound represented by formula (i) above, compounds such as the following, and compounds having both an alicyclic epoxy group and a glycidyl group, such as limonene dioxide.

[0072] The amount of the difunctional epoxy group-containing compound used in the mixing step is sufficiently in excess of the amount of epoxy-reactive functional groups present in the untreated PAS. Preferably, the amount of the difunctional epoxy group-containing compound is 70 molar times or more relative to the amount of epoxy-reactive functional groups, and more preferably 70 molar times or more and 500 molar times or less.

[0073] The reaction between untreated PAS and a difunctional epoxy group-containing compound is preferably carried out under substantially solvent-free conditions. "Substantially solvent-free" means that the presence of inert gases or solids in the reaction system is not prevented, as long as they do not adversely affect the reaction and do not substantially reduce the substrate concentration. Specifically, this means that the total amount of untreated PAS and solvent substances other than the difunctional epoxy group-containing compound is 30% by weight or less and 10% by weight or less relative to the total amount of untreated PAS, the difunctional epoxy group-containing compound, and the solvent substances.

[0074] The reaction temperature is not particularly limited as long as the PAS does not melt or dissolve. For example, 30°C to 230°C is preferred, and 60°C to 150°C is more preferred. The reaction time is typically 30 minutes to 24 hours, and 1 hour to 12 hours is more preferred.

[0075] PAS having MABA-terminated groups may have low molecular weight. Therefore, when reacted with epoxy-containing compounds in a solvent, the PAS having MABA-terminated groups tends to dissolve into the solvent, making recovery difficult and hindering the achievement of the effects of the present invention. For this reason, under substantially solvent-free conditions, it is possible to prevent reactive end groups such as MABA-terminated groups from leaching into the solvent, making it easier to achieve the effects of the present invention.

[0076] Furthermore, under conditions where the untreated PAS melts or dissolves, during the granulation process of PAS(A) after the reaction between the untreated PAS and the difunctional epoxy group-containing compound, unreacted difunctional epoxy group-containing compounds may be incorporated into the particles during granulation. If a large amount of unreacted difunctional epoxy group-containing compounds are incorporated into the PAS particles, these compounds may act as plasticizers, potentially reducing the melt viscosity when added to conventionally known PAS, or increasing volatile matter and / or mold deposits during melt molding. In addition, by reacting the PAS under conditions where the untreated PAS does not melt or dissolve, the unreacted difunctional epoxy group-containing compounds can be removed by washing to an extent that does not hinder the effects of the present invention. As a result, the epoxy group-containing compounds can be recovered from the solution after washing and reused as a raw material for reacting with the untreated PAS.

[0077] As described above, after reacting the untreated PAS with the difunctional epoxy group-containing compound, the solid content in the reaction mixture is recovered by filtration. The recovered solid content is then washed with an organic solvent, water, etc., and / or dried as needed to obtain polyarylene sulfide corresponding to PAS(A). The organic solvent used for washing is preferably selected from ketones, alcohols, or ethers that have a high affinity for the difunctional epoxy group-containing compound without having too high an affinity for PAS(A). Any one of these organic solvents may be used, or two or more may be combined. Furthermore, the washing step for PAS(A) is preferably carried out at 80°C or below, and more preferably at 10°C to 40°C, from the viewpoint of efficiently removing unreacted difunctional epoxy group-containing compounds while increasing the recovery efficiency of PAS(A). The drying step may be the same as the method normally used in the production of PAS, and is preferably carried out at 120°C or below under reduced pressure.

[0078] <Polyarylene sulfide (A)> Polyarylene sulfide (A) has one epoxy group in its molecule and is prepared by a mixture of 3.0 mg of the extract of PAS (A) obtained by Soxhlet extraction using chloroform, 5.0 mg of 1,3,5-trimethoxybenzene, and 0.7 mL of deuterated chloroform, normalized so that the resonance peak based on chloroform in the deuterated chloroform is 7.26 ppm. １ When measured by H-NMR (proton nuclear magnetic resonance), if the integral value of the peak observed in the range of 6.03 to 6.15 ppm is Hs, the integral value of the peak observed in the range of 4.58 to 4.89 ppm is Ha, and the integral value of the peak observed in the range of 4.00 to 4.25 ppm is Hb, then the following equation (I): 1000 × (Ha + Hb / 2) / (Hs / 3) ≥ 0.5 ... (I) is satisfied.

[0079] Regarding equation (I), H Ｓ This is the integral value of the peak originating from the hydrogen atoms bonded to the benzene ring in the reference substance, 1,3,5-trimethoxybenzene. The value obtained by integrating with a starting point of 6.03 ppm and an ending point of 6.15 ppm is defined as Hs, and this value is set to 3000. In this case, if the starting point and / or ending point are located above the baseline, the integral value obtained by aligning it with the baseline near the peak is calculated.

[0080] Furthermore, Ha is the integral value of the peak originating from the hydrogen atom bonded to the carbon atom bonded to the non-carbonyl oxygen atom in the ester bond (-O-CO-) in the group formed by the reaction of an alicyclic epoxy group and an MABA terminal group, and Hb is the integral value of the peak originating from the hydrogen atom bonded to the carbon atom bonded to the non-carbonyl oxygen atom in the ester bond (-O-CO-) in the group formed by the reaction of a glycidyl group and an MABA terminal group.

[0081] Since the peaks corresponding to Ha and Hb are small relative to Hs, the peaks corresponding to Ha and Hb can be confirmed by magnifying the vertical axis by approximately 100 to 1000 times and adjusting the display range. Even when the sample for measurement is prepared using the method described below, impurities or isomers may be present in the sample. Due to the presence of impurities or isomers in the sample, multiple peaks may be observed at 4.58 to 4.89 ppm and / or 4.00 to 4.25 ppm. If multiple peaks are observed in this range, the sum of the integral values ​​of the multiple peaks shall be taken as Ha or Hb, respectively. Also, if the start and / or end points of each peak are not on the baseline, the integral value when aligned with the baseline near the peak shall be used. When Hs is set to 3000, if Ha and / or Hb are less than 0.1, it is determined that the structure corresponding to that peak is not present.

[0082] １ For H-NMR measurement, the sample used is an extract obtained by Soxhlet extraction of PAS(A) using chloroform. In this specification, "extract" refers to the solid obtained after Soxhlet extraction by heating the chloroform solution at 80°C or below to remove the chloroform. A combination of drying at room temperature and pressure or heating and vacuum drying at 80°C or below (e.g., solvent removal using an evaporator) may be used. Chloroform removal is continued until the sum of the weight of the container and the weight of the extract in the container no longer decreases. The method for obtaining the extract can be carried out under the same conditions as the method for determining the amount of extract described later. Here, "amount of extract" refers to the weight of the extract.

[0083] The obtained extract is washed and dried by the following method, and the resulting solids are １ ​This sample will be used for H-NMR measurement. Add 500 times or more weight of acetone to the extract volume, perform ultrasonic cleaning for 10 minutes, and collect the solids using a membrane filter. Next, bring the suction filtration bottle to atmospheric pressure, add 600 times or more weight of acetone to the extract volume on the membrane filter, stir with a spatula for 30 seconds, then reduce the pressure inside the suction filtration bottle using an aspirator, and repeat the filtration operation a total of 5 times. One cycle consists of ultrasonic cleaning and cleaning on the membrane filter. This is repeated a total of 3 times to wash the extract. In addition, during ultrasonic cleaning and cleaning on the membrane filter, the extract is immersed in acetone. The washed extract is dried at 80°C or below. １ It can be used as a sample for 1H-NMR measurement. Drying may be carried out under reduced pressure conditions, for example, an absolute pressure of 10 Torr or less. By washing and drying in this manner, impurities such as unreacted monomers can be removed from the extract.

[0084] The fact that Ha, Hb, and Hs satisfy formula (I) means that the ratio of the integrated peak values ​​derived from specific hydrogen atoms in the groups produced by the reaction between alicyclic epoxy groups and / or glycidyl groups and MABA-terminated groups is high to the integrated peak values ​​derived from hydrogen atoms in the reference substance. In other words, PAS(A) can be said to have a certain abundance of alicyclic epoxy groups and / or glycidyl groups derived from difunctional epoxy group-containing compounds.

[0085] Methods to increase the value of 1000 × (Ha + Hb / 2) / (Hs / 3) include increasing the amount of MABA-terminated groups in the untreated PAS and increasing the amount of the bifunctional epoxy group-containing compound reacted with the untreated PAS, and performing the washing and / or drying steps of the untreated PAS at or below the glass transition temperature of the untreated PAS.

[0086] 1000 × (Ha + Hb / 2) / (Hs / 3) should be 0.5 or more, preferably 1.0 or more, more preferably 1.8 to 4.5, and even more preferably 2.5 to 4.0. Being within this range allows PAS(A) to exhibit a higher melt viscosity when added to conventionally known PAS.

[0087] The presence of an epoxy group in PAS(A) means that １ This can also be confirmed using 1H-NMR. For example, prepare a sample under the same conditions as in formula (I), １ When 1H-NMR is measured, the presence of epoxy groups in PAS(A) can be confirmed when peaks in the range of 3.00–3.20 ppm and / or 2.75–2.83 ppm are observed. Specifically, the 3.00–3.20 ppm peak originates from an alicyclic epoxy group, and the presence of epoxy groups can be determined when the integral value of this peak is 2 times or more relative to Ha. The 2.75–2.83 ppm peak originates from a glycidyl group, and the presence of epoxy groups can be determined when the integral value of this peak is 0.5 times or more relative to Hb. However, even after the above-mentioned pretreatment, unreacted difunctional epoxy group-containing compounds may remain, so the presence of one epoxy group can be confirmed using the following formulas (II) and (III).

[0088] (PAS(B)) Next, PAS(B), which is different from PAS(A), will be described. In this specification, PAS(B) refers to PAS having a melt viscosity of 28 Pa·s, a heat of fusion of 47 J / g, an extract obtained by Soxhlet extraction using chloroform under total reflux for 2.5 hours in an amount of 1.5 to 2.5% by weight relative to the weight of PAS before extraction, and a nitrogen atom content of 550 to 650 ppm by mass. Note that the melt viscosity of PAS(B) being 28 Pa·s and the heat of fusion being 47 J / g means that PAS(B) is of the linear type.

[0089] PAS(B) can be obtained by adjusting the temperature and / or time of the preceding polymerization in the method for producing untreated PAS described above.

[0090] The nitrogen atom content of PAS(B) is determined using the same method as for untreated PAS, employing the trace nitrogen analyzer described in the examples.

[0091] The amount of PAS(B) extract is measured by Soxhlet extraction, which involves a 2.5-hour total reflux extraction using chloroform.

[0092] Soxhlet extraction using chloroform can be carried out by the following method. For example, a fully automated Soxhlet extractor, such as the "Soxtherm 414" manufactured by Gerhard Japan, can be used as the Soxhlet extractor. Specifically, the extraction can be carried out by the method described later in the section on measuring the amount of extract.

[0093] When PAS(A) has one epoxy group, let M1 (Pa·s) be the melt viscosity of PAS(A), let M2 (Pa·s) be the melt viscosity of a mixture consisting of 7.11 g of PAS(A) and 12.80 g of PAS(B), and let X (J / g) be the heat of fusion of the mixture, then the following equations (II) and (III) are satisfied: Ln(M2) > 0.357 × Ln(M1) + 2.14 ... (II) ((M2 - 45648 × EXP(-0.155X)) / ((45648 × EXP(-0.155X))) × 100 > -20 ... (III)

[0094] In this specification, the heat of fusion refers to the value measured using DSC under inert gas conditions in the following steps 1 to 3. Step 1) Heat from 50°C to 340°C at a rate of 10°C / min, and hold at 340°C for 1 minute. Step 2) Following step 1, cool from 340°C to 50°C at a rate of 10°C / min. Step 3) Following step 2, heat from 50°C to 340°C at a rate of 10°C / min.

[0095] Equation (II) shows that the measured melt viscosity of a mixture obtained by mixing multiple resin components is greater than the predicted value. The logarithmic mixing rule is known as a method for determining the average properties of a mixture when different resins are uniformly mixed, based on the physical properties of the different resins. For example, the natural logarithm Ln(MZ) of the predicted melt viscosity of a mixture when resins α and β are mixed is given by... ０ ) is expressed by the following formula (1): Ln(MZ０ ) = Wα × Ln(Mα) + Wβ × Ln(Mβ) ... (1) Here, in equation (1), Mα and Mβ represent the melt viscosity of resin α and resin β respectively, Wα and Wβ represent the weight ratio of each resin to the total weight of resin α and resin β, and MZ ０ The following equations show the predicted melt viscosity of a mixture consisting of resin α and resin β. For a mixture consisting of 7.11 g of PAS(A) and 12.80 g of PAS(B), equation (2) below can be derived by applying it to equation (1) above. Equation (2) below can be transformed into equation (3) below to find the predicted melt viscosity (MZ) when PAS(A) and PAS(B) are mixed in the above ratio. Ln(MZ) = (7.11 / (7.11 + 12.80)) × Ln(M1) + (12.80 / (7.11 + 12.80)) × Ln(28) ... (2) Ln(MZ) = 0.357 × Ln(M1) + 2.14 ... (3)

[0096] When 7.11 g of PAS(A) and 12.80 g of PAS(B) are mixed, PAS(A) and PAS(B) react and bond, resulting in a measured melt viscosity of the mixture that is greater than the predicted value. Therefore, the melt viscosity of PAS(A) (M1) and the measured melt viscosity of the mixture of PAS(A) and PAS(B) (M2) satisfy the aforementioned formula (II). For example, when untreated PAS is reacted with a monofunctional epoxy group-containing compound, the untreated PAS reacts with the epoxy group, so formula (I) may be satisfied. However, no epoxy group is introduced into the PAS, and an alcoholic hydroxyl group is produced by the reaction of the untreated PAS with the epoxy group. Since the alcoholic hydroxyl group has poor reactivity with the functional group contained in PAS, it does not tend to increase the melt viscosity when added to PAS(B). Therefore, by satisfying formula (II), it can be determined that PAS(A) contains one or more epoxy groups in its molecule.

[0097] Formula (III) shows that when PAS(A) and PAS(B) are mixed, the PAS molecule produced by the reaction of PAS(A) and PAS(B) is linear.

[0098] Furthermore, the difference between the predicted melt viscosity of the above mixture and the measured melt viscosity can be used to determine whether the PAS molecules produced by the reaction of PAS(A) and PAS(B) are linear. Specifically, the error rate is calculated by subtracting the predicted melt viscosity from the measured melt viscosity of the mixture, relative to the predicted melt viscosity obtained from the relationship between melt viscosity and heat of fusion. If the error rate is greater than -20%, it can be determined that the PAS molecules produced by the reaction of PAS(A) and PAS(B) are linear.

[0099] More specifically, the heat of fusion and melt viscosity were measured for four types of linear PAS (PAS-1 to PAS-4) produced according to the method for producing untreated PAS described above, using the method described above. The measurement results are as follows: PAS-1: Heat of fusion 35 J / g, melt viscosity 220 Pa·s PAS-2: Heat of fusion 37 J / g, melt viscosity 130 Pa·s PAS-3: Heat of fusion 47 J / g, melt viscosity 30 Pa·s PAS-4: Heat of fusion 50 J / g, melt viscosity 20 Pa·s

[0100] The above-mentioned measurement results for heat of fusion and melt viscosity were plotted on a coordinate plane where the x-axis for heat of fusion and the y-axis for melt viscosity are orthogonal, using Microsoft Excel® software. Using the aforementioned Excel function, an exponential approximation formula was obtained for the data plotted on the coordinate plane as described above, resulting in the following equation (4), which represents the relationship between heat of fusion and melt viscosity. Here, x is the heat of fusion (J / g) and y is the melt viscosity (Pa·s). y = 45648 × EXP(-0.155x) ... (4)

[0101] Here, the heat of fusion of a mixture consisting of 7.11 g of PAS(A) and 12.80 g of PAS(B) is X. Therefore, the predicted melt viscosity (MZ) of the mixture is expressed by the following formula (5): MZ = 45648 × EXP(-0.155X) ... (5) In order to suppress sampling irregularities when measuring the heat of fusion, the mixture prepared with the above mixing ratio is melted and kneaded under temperature conditions where the PAS melts but does not decompose (for example, below 310°C) and the resulting mixture is used as the measurement sample. For example, the sample may be one recovered after melt viscosity measurement, and a mixture melted and kneaded in a melting kneader at 310°C for 5 minutes is an example.

[0102] Since the measured melt viscosity of the mixture is M2, the difference between the measured melt viscosity and the predicted melt viscosity of the mixture is expressed as M2 - 45648 × EXP(-0.155X). Therefore, the error rate obtained from the difference between the measured melt viscosity and the predicted melt viscosity of the mixture is expressed by the following formula (6). Crosslinked PAS has a lower degree of crystallinity than linear PAS, so even if the melt viscosity is similar, the heat of fusion will be lower than that of linear PAS. Therefore, when the error rate is greater than -20%, it is judged to be linear PAS. Error rate (%) = ((M2 - 45648 × EXP(-0.155X)) / (45648 × EXP(-0.155X))) × 100 ... (6)

[0103] For example, when untreated PAS is reacted with a polyfunctional epoxy group-containing compound having three or more epoxy groups in one molecule, the untreated PAS and epoxy groups react, so formula (I) may be satisfied. However, because the molecule has two or more epoxy groups, when added to PAS(B), a branched structure is introduced, the heat of fusion becomes smaller relative to the melt viscosity, and as a result the error rate becomes smaller than -20%. Therefore, by satisfying formula (III), it can be determined that PAS(A) does not contain two or more epoxy groups at the same end. Also, since formula (III) is not satisfied when bonded to the arylene group, which is the repeating unit of PAS(A), it can be determined that the PAS(A) epoxy group is at the end of the molecular chain. Therefore, having one epoxy group in a molecule can be rephrased as having at least one epoxy group at one end. Since PAS has two ends per molecule, it may contain one epoxy group at each of the two ends, or it may contain one epoxy group at one end. Furthermore, if the Ar in PAS(A) is a p-phenylene group, an m-phenylene group, an o-phenylene group, a p,p'-diphenylene sulfone group, a p,p'-biphenylene group, a p,p'-diphenylene ether group, and a naphthalene group, and satisfies formula (III), then it can be determined that the epoxy group is at the end of the molecular chain.

[0104] Conventional PAS can contain various terminal functional groups such as the MABA terminal group, phenolic hydroxyl group, and mercapto group mentioned above. Epoxy groups derived from difunctional epoxy group-containing compounds exhibit good reactivity with many of the terminal functional groups contained in conventionally known PAS. Therefore, they can react well with PAS(A) without finely adjusting the amount of functional groups in conventionally known PAS, thus achieving the effects of the present invention. Furthermore, when producing linear PAS with high melt viscosity by polymerization, it is necessary to extend the polymerization time at high temperatures. In this case, it can be difficult to obtain PAS with high melt viscosity due to the simultaneous occurrence of PAS decomposition reactions. On the other hand, in the present invention, linear PAS with high melt viscosity can be obtained without PAS decomposition reactions. Here, PAS(B) used in formulas (II) and (III) above is subject to predetermined conditions, as it is used as a reference substance to indicate that PAS(A) has one epoxy group. Therefore, it can be said that PAS(A) will produce the same effects as the present invention even when used with a linear PAS other than PAS(B). In addition, when a conventionally known PAS reacts with PAS(A), two molecules of alcoholic hydroxyl groups derived from the epoxy group in the bifunctional epoxy group-containing compound are produced. Since alcoholic hydroxyl groups have a strong interaction with silanol groups, the PAS obtained by the reaction of a conventionally known PAS with PAS(A) exhibits excellent adhesion to silicon compounds such as glass fibers.

[0105] In PAS(A), the specific surface area is 5 m². ２ / g or more 120m ２ Preferably less than / g, and 10m ２ / g or more 100m ２ More preferably less than / g, and 30m ２ / g or more 90m ２A value of less than or equal to / g is even more preferable. The fact that the specific surface area of ​​PAS(A) is within the above numerical range indicates that PAS(A) is in the form of a microporous powder, which is a characteristic that distinguishes PAS from resin compositions and molded articles obtained by melt-kneading a composition containing a bifunctional epoxy group-containing compound. Furthermore, being within the above range results in excellent washability, which reduces the amount of gas generated during melt-kneading and prevents deterioration of physical properties due to the plasticizing effect derived from unreacted epoxy group-containing compounds. The specific surface area of ​​PAS(A) is usually adjusted by adjusting the specific surface area of ​​untreated PAS.

[0106] In PAS(A), the melt viscosity should be 1 Pa·s or more, preferably 1 Pa·s to 250 Pa·s, more preferably 15 Pa·s to 100 Pa·s, and even more preferably 20 Pa·s to 100 Pa·s. Furthermore, as shown by the logarithmic mixing rule described above, when using PAS(A), it is preferable to use PAS(A) having a melt viscosity equivalent to or greater than that of conventionally known PAS.

[0107] PAS(A) preferably satisfies the following formula (IV): 1000 × (Hb / 2) / (Hs / 3) < 0.2 ... (IV)

[0108] The fact that Hb and Hs in PAS(A) satisfy formula (IV) indicates that the amount of functional groups produced by the reaction of the glycidyl group and the MABA terminal group is small. In other words, it means that PAS(A) has no glycidyl group or very few glycidyl groups. The lower limit of 1000 × (Hb / 2) / (Hs / 3) is not particularly limited, but may be 0.

[0109] PAS(A) preferably satisfies the following formula (V): 1000 × Ha / (Hs / 3) ≥ 1.8 ... (V)

[0110] The fact that Ha and Hs in PAS(A) satisfy formula (IV) indicates a large amount of functional groups produced by the reaction of the alicyclic epoxy compound with the MABA terminal group. In other words, it indicates that there is a large amount of PAS having epoxy groups derived from the alicyclic epoxy compound. The upper limit of 1000 × Ha / (Hs / 3) is not particularly limited, but is preferably 4.5 or less, and more preferably between 2.5 and 4.0.

[0111] The present invention is not limited to the embodiments described above, and various modifications are possible. Embodiments obtained by appropriately combining the technical means disclosed in this specification are also included within the technical scope of the present invention. Furthermore, all documents cited in this specification are incorporated herein by reference.

[0112] The present invention will be described in more detail below with reference to examples and comparative examples. The methods for measuring various characteristics and physical properties are as follows.

[0113] <Measurement Method> [Method for Measuring Melt Viscosity] The melt viscosity was measured using a Toyo Seiki Capillograph F-1. A 1 mmφ × 10 mm inlet angle die was used as the capillary. 19.9 g to 20.0 g of PPS was placed in a barrel heated to 310°C and held for 5 minutes, then subjected to a shear rate of 1200 sec. －１ The melt viscosity was measured using [method / tool ​​name].

[0114] [Method for Measuring Extract Volume] The amount of extract obtained from 3.0 g of PPS using chloroform was measured using a fully automatic Soxhlet extractor (Soxtherm 414) manufactured by Gerhard Japan. The extraction conditions were a heating temperature of 170°C, a boiling extraction time of 60 minutes, and a washing extraction time of 90 minutes, with 150 mL of chloroform used as the solvent. The total extraction time was 2.5 hours, which is the sum of the boiling extraction time and the washing extraction time. After the extraction operation was completed, the glass container of the Soxhlet extractor containing the extract was left in a fume hood at room temperature for 15 hours to allow some of the chloroform to evaporate. Then, it was placed in a vacuum dryer and dried under reduced pressure at 80°C for 4 hours to dry the extract in the glass container. After removing the glass container from the vacuum dryer, the temperature of the glass container was returned to room temperature in a desiccator. Subsequently, the total weight of the obtained extract and the glass container was measured. The weight of the extract obtained by the extraction procedure was calculated by subtracting the weight of the dry glass container, which was measured before the extraction procedure and stored in a desiccator, from the measured total weight. The extract amount (weight %), which is the ratio of the weight of the extract to the weight of PPS, was calculated using the following formula (7): Extract amount (weight %) = Weight of the extract obtained by the extraction procedure (g) / Weight of the sample used in the extraction procedure (g) × 100 ... (7)

[0115] [Method for measuring nitrogen atom content] 10 mg of PPS was accurately weighed, and the nitrogen atom content (mass ppm) was determined by elemental analysis using a trace nitrogen analyzer (TN-2100H, manufactured by Nitto Seiko Analytech Co., Ltd.). The nitrogen atom content (μmol / g) was calculated by dividing this by the atomic weight of nitrogen (14.00), and this value was taken as the MABA terminal group weight. The temperature of the sample injection section was set to 800°C, the temperature of the reaction section to 900°C, and the gas flow rate to 300 mL / min. A calibration curve was prepared using a toluene solution of pyridine with a known concentration.

[0116] [Method for Measuring Heat of Fusion] 10.0 mg of PPS sample was weighed into an aluminum sample pan, and the heat of fusion was measured using a differential scanning calorimeter (DSC 3+) manufactured by Mettler Toledo. An aluminum sample pan equivalent to the PPS sample container was used as a reference. For the measurements of mixtures 1 to 10 described below, samples were used after the measurement of melt viscosity. Specifically, measurements were performed using a differential scanning calorimeter (DSC) by a method that satisfies the conditions of steps 1 to 3 below, and the heat of fusion was determined from the DSC curve obtained in step 3. The measurements were performed under nitrogen atmosphere conditions. Step 1) Heat from 50°C to 340°C at a rate of 10°C / min, and hold at 340°C for 1 minute. Step 2) Following step 1, cool from 340°C to 50°C at a rate of 10°C / min. Step 3) Following step 2, heat from 50°C to 340°C at a rate of 10°C / min.

[0117] [Method for measuring Na content] 0.5 g of PPS, 5 mL of 96% by mass sulfuric acid, and 2 mL of 33±3% by mass hydrogen peroxide solution were added to a 30 mL Kelder flask and heated for 40 minutes. After heating, the entire volume was transferred to a 50 mL volumetric flask and diluted with pure water. The Na content of the obtained solution was determined by analyzing it using ICP-AES (Hitachi High-Tech Corporation, ICP emission spectrometer "SPS3500DD"). The Na content was determined by interpolation using a calibration curve prepared with commercially available standard solutions.

[0118] [Method for Measuring Specific Surface Area] The specific surface area was measured using the BET method (single-point method) in accordance with ISO 9277, using a specific surface area measuring device (Anton Paar, "Monosorb®"). 0.1 g of PPS was placed in a sample cell, and the sample was heated at 105°C for 3 hours while flowing a mixed gas of nitrogen and helium (nitrogen:helium = 30:70 (volume ratio)). After the heated sample cooled to room temperature (23°C), the sample cell was cooled with liquid nitrogen to adsorb nitrogen gas onto the sample. Adsorption was considered complete when the fluctuation of the nitrogen flow rate stopped. After adsorption was complete, cooling was stopped and nitrogen was desorbed. Desorption was considered complete when the fluctuation of the nitrogen flow rate stopped. The specific surface area of ​​PPS was calculated using the following formula (8). Specific surface area (m²) ２ / g) = Surface area of ​​the sample (m²) calculated from the nitrogen adsorption amount based on ISO 9277 ２ ) / Sample weight (weight after attachment / detachment - container weight) (g) ... (8)

[0119] [ １ H-NMR measurement method] [ １ [Preparation of H-NMR Measurement Sample] 10 mg of Soxhlet extract, obtained by the same method as for measuring the amount of extract, and 5 g of acetone were added to a 30 mL vial, and ultrasonic washing was performed for 10 minutes. The washed extract was recovered by filtration using a membrane filter. On the recovered solids, 6 g of acetone was added to the suction filter bottle under atmospheric pressure, and after stirring with a spatula for 30 seconds, the suction filter bottle was reduced in pressure using an aspirator and filtered. This operation was repeated a total of five times. Furthermore, the ultrasonic washing, filtration, and washing on the membrane filter were repeated two more times to obtain a washed extract. The amount of acetone used in the second and subsequent washing operations was the same as in the first operation. The thus washed extract was dried at 80°C for 4 hours under reduced pressure. １ A sample for H-NMR measurement was obtained.

[0120] [ １ H-NMR measurement conditions] １ A mixture of 3.0 mg of sample for H-NMR measurement, 7.0 mL of deuterated chloroform, and 5.0 mg of 1,3,5-trimethoxybenzene is prepared. １ The sample was prepared for 1H-NMR measurement. The measurement conditions were as follows. The results were analyzed using Delta for Windows v6.3.0 from JEOL Ltd. The chloroform-based resonance peak in deuterated chloroform was normalized to 7.26 ppm. １ Based on the 1H-NMR measurement results, the integral values ​​of the peaks observed in the range of 6.03 to 6.15 ppm were defined as Hs, the integral value of the peaks observed in the range of 4.58 to 4.89 ppm as Ha, and the integral value of the peaks observed in the range of 4.00 to 4.25 ppm as Hb. Equations (I), (IV), and (V) below were calculated. The results are shown in Table 1. The same method was also used in Example 1 and Comparative Example 2, which will be described later. １H-NMR measurements were performed. The values ​​of 1000 × (Ha + Hb / 2) / (Hs / 3) and 1000 × (Hb / 2) / (Hs / 3) calculated based on Ha and Hb are also shown in Table 1. (Measurement conditions) Apparatus: JNM-ECZ600R / S1 (manufactured by JEOL Ltd.) Resonance frequency: 600 MHz Measurement temperature: Room temperature (23°C; no temperature adjustment) Number of cumulative measurements: 8192 (Formulas used for calculation) 1000 × (Ha + Hb / 2) / (Hs / 3) ... (I) 1000 × (Hb / 2) / (Hs / 3) ... (IV) 1000 × Ha / (Hs / 3) ... (V)

[0121] [Synthesis Example 1 (Untreated PPS-1)] 5000g of NMP was placed in a 20L autoclave. After creating a nitrogen gas atmosphere inside the autoclave, the NMP inside the autoclave was heated to 100°C over 1 hour while stirring at a stirrer speed of 250 rpm. After reaching 100°C, 1200g of a 74.0% by mass NaOH aqueous solution, 21.4 moles of NaSH, and Na ２ 2000 g of an aqueous sulfur source solution containing 0.36 moles of sulfur, along with 1000 g of NMP, were added to an autoclave. The mixture in the autoclave was then gradually heated to 200°C over 2 hours. During the heating process to 200°C, 1028 g of water, 760 g of NMP, and 0.36 moles of hydrogen sulfide were discharged from the autoclave.

[0122] Next, the mixture in the autoclave was cooled to 170°C, and at the same temperature, 3359 g of p-dichlorobenzene (p-DCB), 2920 g of NMP, 173 g of water, and 5.9 g of 97% by mass of NaOH were added to the autoclave. At the end of the addition, the temperature of the mixture in the autoclave was 130°C. Next, while stirring at a stirrer speed of 250 rpm, the mixture in the autoclave was heated to 180°C over 30 minutes, and then heated from 180°C to 220°C over 60 minutes. After that, the mixture in the autoclave was heated to 260°C over 90 minutes to carry out the preliminary polymerization.

[0123] After the initial polymerization stage was completed, the stirrer speed was increased to 400 rpm, and 443 g of water was injected into the autoclave as a phase-separating agent. After the injection of water, the temperature of the reaction solution was raised to 260°C in 0.5 hours, and the reaction was continued at the same temperature for 3 hours to carry out the subsequent polymerization stage.

[0124] After the subsequent polymerization was completed, the reaction mixture was cooled to near room temperature and then sieved through a 100-mesh screen to recover granular polymer from the reaction mixture. After sieving, the recovered granular polymer was washed three times with acetone, three times with water, once with a 0.3 wt% aqueous acetic acid solution, and four times with water, in that order, at room temperature (23°C). All washing operations were carried out under conditions where the PPS was fully immersed in washing solvent in an amount at least five times the weight of the PPS recovered by sieving through the screen. The washed granular polymer was dried under reduced pressure at 80°C for 4 hours to obtain untreated PPS-1. The obtained untreated PPS-1 corresponds to the polyarylene sulfide (B) (PAS(B)) described above. Hereinafter, the obtained untreated PPS-1 will also be referred to as PPS(B).

[0125] [Synthesis Example 2 (Untreated PPS-2)] 5000 g of NMP was placed in a 20 L autoclave. After creating a nitrogen gas atmosphere inside the autoclave, the NMP in the autoclave was heated to 100°C over 1 hour while stirring at 250 rpm. After reaching 100°C, 1470 g of a 74.0 mass% NaOH aqueous solution, 2340 g of a 62.4 mass% NaSH aqueous solution, and 1000 g of NMP were added to the autoclave. The mixture in the autoclave was then gradually heated to 200°C over 2 hours. During the heating to 200°C, 1200 g of water, 800 g of NMP, and 0.36 moles of hydrogen sulfide were discharged from the autoclave.

[0126] Next, the mixture in the autoclave was cooled to 170°C, and at the same temperature, 3973 g of p-DCB, 2466 g of NMP, 26 g of water, and 2 g of NaOH at a concentration of 97% by mass were added to the autoclave. At the end of the addition, the temperature of the mixture in the autoclave was 130°C. Next, while stirring at a stirrer speed of 250 rpm, the mixture in the autoclave was heated to 180°C over 30 minutes, and then heated from 180°C to 220°C over 60 minutes. After that, the mixture in the autoclave was heated to 260°C over 90 minutes to carry out the preliminary polymerization.

[0127] After the initial polymerization was completed, the stirrer speed was increased to 400 rpm, and 443 g of water was injected into the autoclave as a phase separating agent. After the injection of water, the temperature of the reaction solution was raised to 260°C over 0.5 hours, and the reaction was continued at the same temperature for 3 hours to carry out the subsequent polymerization.

[0128] The recovery and post-treatment steps following the subsequent polymerization were carried out in the same manner as in Production Example 2 to obtain untreated PPS-2.

[0129] [Synthesis Example 3 (Untreated PPS-3)] Untreated PPS-3 was obtained by using 3379 g of p-DCB as the starting material, and carrying out the recovery and post-treatment steps following the subsequent polymerization in the same manner as in Production Example 1, except that acetone washing was performed three times followed by water washing three times.

[0130] The melt viscosity, heat of fusion, extract amount, nitrogen atom content, specific surface area, and Na content of the untreated PPS-1 to PPS-3 obtained in Synthesis Examples 1 to 3 were measured using the measurement method described above. The measurement results are shown in Table 1.

[0131]

[0132] [Example 1] 16 g of untreated PPS-1 obtained in Synthesis Example 1, 40 g of the bifunctional alicyclic epoxy group-containing compound-1 represented by the above formula (i-9) (X-40-2669, manufactured by Shin-Etsu Chemical Co., Ltd.), and a stirring bar were placed in a 100 mL round-bottom flask. The contents of the round-bottom flask were stirred at 120°C for 8 hours to react the untreated PPS-1 with epoxy compound-1. After the reaction, the mixture was allowed to cool to room temperature, and the solids were collected from the reaction solution in the round-bottom flask using filter paper (No. 5A). The collected solids were transferred to the filter paper, and approximately 50 g of acetone was added to the suction filtration bottle under atmospheric pressure. The mixture was stirred with a spatula for 30 seconds, and then filtered under reduced pressure using an aspirator. This process was repeated a total of three times (i.e., 150 g of acetone was used for washing). Next, the washed solids, 100 g of acetone, and a stirring bar were placed in a 200 mL round-bottom flask. The contents of the flask were then stirred for 30 minutes. After stirring, the solids were collected from the reaction solution in the flask using filter paper. The washing process on the filter paper and the washing in acetone were repeated once. During the washing on the filter paper and the stirring in acetone, the entire solid was immersed in the acetone. The washed solids were dried under reduced pressure at 80°C for 4 hours to obtain PPS modified with the epoxy compound-1 described above (terminated PPS-1).

[0133] [Example 2] End-treated PPS-2 was obtained in the same manner as in Example 1, except that untreated PPS-2 was used.

[0134] [Example 3] 16 g of untreated PPS-2, 40 g of bifunctional bisphenol A type epoxy compound-2 (jER828, manufactured by Mitsubishi Chemical Corporation), and a stirring bar were placed in a 100 mL round-bottom flask. The contents of the round-bottom flask were stirred at 120°C for 8 hours to react the untreated PPS with the bifunctional epoxy compound-1, except that the procedure was the same as in Example 1 to obtain end-treated PPS-3.

[0135] [Comparative Example 1] Untreated PPS-1 was used.

[0136] [Comparative Example 2] The same procedure as in Example 1 was followed, except that untreated PPS-3 was used, to obtain end-treated PPS-4.

[0137] [Comparative Example 3] 16 g of untreated PPS-1, 40 g of epoxy compound-1, 40 g of NMP, and a stirring bar were placed in a 200 mL round-bottom flask and reacted at 120°C for 8 hours. Recovery and washing after the reaction were carried out in the same manner as in Example 1 to obtain end-treated PPS-5.

[0138] [Comparative Example 4] The procedure was carried out in the same manner as in Example 1, except that a monofunctional alicyclic epoxy compound-3 (cyclohexene oxide) was used as the epoxy group-containing compound, to obtain terminally treated PPS-6.

[0139] [Comparative Example 5] The same procedure as in Example 1 was followed, except that a trifunctional alicyclic epoxy compound-3 (KR-470, manufactured by Shin-Etsu Chemical Co., Ltd.) was used as the epoxy group-containing compound, to obtain terminally treated PPS-7.

[0140] In Examples 1 to 3 and Comparative Examples 2 to 5, the end-treated PPS-1 to PPS-7, and in the untreated PPS-1 of Comparative Example 1, the melt viscosity, specific surface area, Na content, and １ H-NMR measurements were performed using the measurement method described above. １ The above equations (I), (IV), and (V) were calculated from the H-NMR measurement results. The results are shown in Table 2.

[0141]

[0142] (Preparation of mixtures with PPS(B)) [Examples 1-3, Comparative Examples 2-5] 7.11 g of the end-treated PPS obtained in Examples 1-3 and Comparative Examples 2-5, and 12.80 g of PPS(B) were placed in an antistatic polyethylene bag and shaken by hand for 1 minute under room temperature (23°C ± 1°C) and relative humidity of 63 RH% to obtain PPS mixtures 1-7. At this time, the number of shakes per minute was at least 60, and the number of shakes in one direction was counted as 1.

[0143] [Comparative Example 1] 19.91 g of untreated PPS-1 and 0.010 g of 3-aminopropyltriethoxysilane were added to an antistatic polyethylene bag and shaken by hand for 1 minute at room temperature (23°C ± 1°C) and relative humidity of 63 RH% to obtain PPS mixture 8.

[0144] [Comparative Example 6] 19.91 g of untreated PPS-1 and 0.150 g of epoxy compound-1 were added to an antistatic polyethylene bag and shaken by hand for 1 minute at room temperature (23°C ± 1°C) and relative humidity of 63 RH% to obtain PPS mixture 9.

[0145] [Comparative Example 7] The same procedure as in Comparative Example 6 was followed, except that the amount of epoxy compound-1 was 0.300 g, to obtain PPS mixture 10.

[0146] (Measurement of melt viscosity and heat of fusion) For mixtures 1 to 10 obtained in Examples 1 to 3 and Comparative Examples 1 to 7, the melt viscosity (M2) and heat of fusion (X) were obtained by measuring them in the same manner as described above.

[0147] (Calculation of Equations (II) to (III)) The melt viscosity (M1) of end-treated PPS1 to 7 and untreated PPS-1, the melt viscosity (M2) of mixtures 1 to 10, and the heat of fusion (X) were substituted into the following equations (II) and (III) to obtain values ​​for each equation. For Comparative Examples 6 and 7, the melt viscosity (M1) was the same as that of untreated PPS-1 as in Comparative Example 1. Ln(M2) > 0.357 × Ln(M1) + 2.14 ... (II) ((M2 - 45648 × EXP(-0.155X)) / (45648 × EXP(-0.155X))) × 100 > -20 ... (III)

[0148] (Evaluation of Thickening Properties) The melt viscosity (M1) of end-treated PPS1 to 7 and untreated PPS-1, and the melt viscosity (M2) of mixtures 1 to 10 were substituted into the following formula (VI) to evaluate the thickening properties when melt-mixed with PPS(B). Note that Ln represents the natural logarithm. Ln(M2) / (0.357 × Ln(M1) + 2.14) ... (VI)

[0149] Formula (VI) is a modified form of formula (II), and if formula (V) is 1.10 or greater, it is determined that sufficient thickening has occurred.

[0150] Table 3 shows the melt viscosity (M2), heat of fusion X, calculation results of formulas (II) to (III), evaluation results of thickening properties, and the number of epoxy groups introduced into the terminal-treated PPS based on the results of formulas (II) and (III) for mixtures 1 to 10 obtained in Examples 1 to 3 and Comparative Examples 1 to 7. In Table 3, "Asi" represents 3-aminopropyltriethoxysilane.

[0151]

[0152] Furthermore, for the mixture 9 obtained in Comparative Example 6, 1 g was taken from the sample after the melt viscosity measurement, and it was pulverized using a pulverizer (Yamamoto Electric Co., Ltd., multi-purpose flour mill New Yomekko-san (without J-cutter)) to be used as the measurement sample. Otherwise, it was measured under the same conditions as the specific surface area measurement method described above. As a result, the specific surface area was 1 m² ２ It was less than / g.

[0153] Tables 2-3 show that PAS having one epoxy group in the molecule and satisfying formula (I) (i.e., PAS satisfying formulas (I) to (III)) can be blended with conventionally known PAS (PPS(B)) to sufficiently increase the melt viscosity of the PAS without introducing a branched structure to the PAS.

[0154] [Discussion] Comparative Examples 2 and 3 showed low viscosity evaluation results of less than 1.10 when mixed with PPS(B). Comparative Example 2 also showed a low value of less than 0.2 for formula (I), suggesting that the reaction between untreated PPS-3 and epoxy group-containing compound-1 did not proceed sufficiently. Since only the type of untreated PPS differed from Example 1, it is thought that untreated PPS with a high Na content is less likely to react with epoxy group-containing compounds. Furthermore, Comparative Example 3 used untreated PPS-1, but differed from Example 1 in that the experiment was conducted in an NMP solvent. It is presumed that the PPS chain having MABA-terminated groups that react with the bifunctional epoxy group-containing compound was easily dissolved in the NMP solvent, which has a high affinity for PPS, making it difficult to recover as solid content.

[0155] Comparative Example 4 did not exhibit thickening properties when mixed with PPS(B). This is thought to be because a monofunctional epoxy group-containing compound was used as the epoxy group-containing compound. When there is only one epoxy group in one molecule, an alcoholic hydroxyl group is introduced at the end of the PPS molecular chain by reaction with the epoxy group. However, conventionally known PPS does not have a functional group that can react with an alcoholic hydroxyl group to form a bond without a catalyst, so no bonding occurs in the PPS chain, and as a result, it did not exhibit thickening properties. Formula (II) also supports the idea that terminal-treated PPS-6 does not have an epoxy group.

[0156] Comparative Example 5 showed a high viscosity of 1.20 when mixed with PPS(B), but its heat of fusion was low and it did not satisfy formula (III). This is thought to be because a trifunctional epoxy compound was used as the epoxy group-containing compound, resulting in the introduction of a branched structure when it reacted with PPS(B).

[0157] In Comparative Example 6, when untreated PPS-1 and a difunctional epoxy group-containing compound were mixed and melt-kneaded without prior end treatment with the difunctional epoxy group-containing compound, formulas (II) and (III) were satisfied, but the viscosity was low at 1.07. In Comparative Example 7, the amount of difunctional epoxy group-containing compound added was increased, but similar results were obtained. This is thought to be because, when added during melt-kneading, sufficient viscosity increase was not achieved due to the volatilization of the difunctional epoxy group-containing compound and the plasticizing effect of the remaining unreacted difunctional epoxy group-containing compound.

[0158] Comparing Examples 1 and 2, Example 2 showed a larger value of formula (I) and exhibited higher viscosity when mixed with PPS(B). This is thought to be due to the amount of MABA end groups in the untreated PPS used as the raw material for the end-treated PPS, resulting in the introduction of epoxy groups to more PPS ends. Comparing Examples 1 and 3, Example 3 showed a smaller value of formula (I) and lower viscosity when mixed with PPS(B). From these results, it can be said that alicyclic epoxy compounds have better reactivity with PPS end functional groups than glycidyl group-containing compounds. The reaction between epoxy groups and PAS end groups such as MABA end groups is considered to be a nucleophilic substitution reaction. In the case of glycidyl group-containing compounds, S Ｎ While reacting in two ways, in the case of alicyclic epoxy group-containing compounds, S Ｎ It reacts in the same way. Therefore, in PPS with reduced Na content, i.e., PPS where the MABA terminal group etc. is acidic, S Ｎ It is presumed that this result was obtained because the alicyclic epoxy compound, which can promote the cleavage of epoxy groups, reacts better with the glycidyl group-containing compound, which reacts in two ways, than with the glycidyl group-containing compound, which reacts in two ways.

Claims

1. A mixture of 3.0 mg of an extract of a polyarylene sulfide having one epoxy group in its molecule, obtained by Soxhlet extraction using chloroform, 5.0 mg of 1,3,5-trimethoxybenzene, and 0.7 mL of deuterated chloroform, normalized so that the resonance peak based on chloroform in the deuterated chloroform is 7.26 ppm. １ Polyarylene sulfide satisfying the following equation (I): 1000 × (Ha + Hb / 2) / (Hs / 3) ≥ 0.5 ... (I), where Hs is the integral of the peak observed in the range of 6.03 to 6.15 ppm by 1H-NMR, Ha is the integral of the peak observed in the range of 4.58 to 4.89 ppm, and Hb is the integral of the peak observed in the range of 4.00 to 4.25 ppm.

2. The polyarylene sulfide according to claim 1, wherein Hb and Hs satisfy the following formula (IV): 1000 × (Hb / 2) / (Hs / 3) < 0.2 ... (IV).

3. A method for producing polyarylene sulfide, comprising: a mixing step of mixing untreated polyarylene sulfide with a compound containing a bifunctional epoxy group; and a reaction step of reacting the mixture obtained in the mixing step at a temperature of 30°C or higher and 230°C or lower under substantially solvent-free conditions, wherein the untreated polyarylene sulfide has a specific surface area of ​​5 m² as measured by the BET method (single-point method) using a mixed gas of nitrogen and helium (nitrogen:helium = 30:70 (volume ratio)) as the adsorption gas. ２ The value is greater than or equal to / g, at a temperature of 310°C and a shear rate of 1200 sec. －１ A method for producing polyarylene sulfide, wherein the melt viscosity measured under the following conditions is 1 Pa·s or more, the amount of functional groups that react with epoxy groups is 14 μmol / g or more, and the sodium content is 800 ppm by mass or less.

4. The method for producing polyarylene sulfide according to claim 3, wherein the heating time in the reaction step is 30 minutes or more and 24 hours or less.

5. The method for producing polyarylene sulfide according to claim 3 or 4, wherein the amount of functional groups that react with the epoxy groups of the untreated polyarylene sulfide is the nitrogen atom content.

6. The method for producing polyarylene sulfide according to claim 3 or 4, further comprising a step of washing the untreated polyarylene sulfide at a temperature below its glass transition temperature and / or drying it, prior to the mixing step.

7. The method for producing polyarylene sulfide according to claim 3 or 4, wherein the amount of the bifunctional epoxy group-containing compound in the mixing step is 70 molar times or more relative to the nitrogen atom content of the untreated polyarylene sulfide.

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