JP2008280495A - Process for producing polyarylene sulfide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process for producing a polyarylene sulfide in a short period of time with good efficiency because of the high rate of polymerization reaction. <P>SOLUTION: The process for producing a polyarylene sulfide comprises subjecting at least a sulfiding agent and a poly-halogenated aromatic compound to polymerization reaction in the presence of an organophosphate having a structural formula represented by formula (I) (wherein R<SP>1</SP>, R<SP>2</SP>, R<SP>3</SP>and R<SP>4</SP>are each independently a substituent including any of hydrogen, an alkyl group, an aromatic group, phosphorus, nitrogen, sulfur and the like; and Q<SP>-</SP>is an anion). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing polyarylene sulfide. More specifically, the present invention relates to a method for producing polyarylene sulfide efficiently in a short time with a high polymerization reaction rate.

  In recent years, special physical properties of organic sulfur compounds, particularly aliphatic sulfur compounds and aromatic sulfur compounds (thiols, thioketones, thioethers, thioacids, etc.) have attracted attention and are frequently used in medicines, agricultural chemicals, industrial chemicals, and the like. In addition, a large number of aromatic polymer compounds (polyarylene sulfide, hereinafter also referred to as PAS) having sulfur as a bond have been produced. Such a sulfur-containing aromatic polymer compound is usually produced by contacting and reacting a halogenated aromatic compound and an alkali metal sulfide to remove the alkali metal halide, for example, polyarylene. The sulfide can be obtained by polymerizing a polyhalogenated aromatic compound and an alkali metal sulfide in contact with each other in an organic polar solvent.

  As a specific method for producing this PAS, an alkali metal sulfide such as sodium sulfide and a polyhalogenated aromatic compound such as p-dichlorobenzene are reacted in an organic amide solvent such as N-methyl-2-pyrrolidone. A method has been proposed, but only PAS with low molecular weight and low melt viscosity can be obtained. In addition, a commonly practiced method is to remove the water contained in the hydrous sodium sulfide by heating sodium sulfide containing a large amount of water of crystallization in one or more moles of an organic amide solvent per mole of the sulfur component of the sodium sulfide. In this method, a sulfidizing agent is prepared by adding p-dichlorobenzene and polymerized by heating. Not only does it take a long time to remove the water from the hydrous sodium sulfide, but also the sulfide obtained by this method. In the agent, 1.0 mol or more of water per 1 mol of sulfur component of the sulfidizing agent remains, so that it takes a long time to obtain PAS (for example, see Patent Document 1). ).

  As a method for solving the problems in the above-described method, that is, a method that requires a long time for the reaction, a method using a highly reactive alkali metal sulfide (see, for example, Patent Document 2 and Patent Document 3) is disclosed. In Patent Document 2, anhydrous alkali metal sulfide is used, and it is considered that the reactivity is high. However, in this method, it is essential to use anhydrous alkali metal sulfide. It required a lot of energy and a long time, so it was not sufficient for commercial production. In Patent Document 3, sodium sulfide hemihydrate is used as an alkali metal sulfide and is considered to have relatively high reactivity. The manufacturing method is complicated and expensive, and lacks industrial qualification.

Furthermore, although a method of polymerizing polyphenylene sulfide in the presence of a quaternary phosphonium salt is also disclosed (see, for example, Patent Document 4), a halogenated aromatic thiol or dithiol is used as a monomer, and these are expensive, Lack of industrial qualification.
Japanese Examined Patent Publication No. 45-3368 (page 13) JP-A-4-145127 (pages 2 and 3) JP-A-64-9229 (pages 3 to 5) JP 59-81335 (first page)

  The present invention has been achieved as a result of studying the solution of the problems in the prior art described above as an issue. Therefore, an object of the present invention is to provide a method for producing a polyarylene sulfide efficiently in a short time with a high polymerization reaction rate.

The present invention employs the following means in order to solve such problems. That is, the present invention is as follows.
1. A method for producing polyarylene sulfide, comprising reacting a sulfidizing agent and a polyhalogenated aromatic compound in an organic solvent in the presence of an organic phosphorus salt represented by the following general formula (I).

(However, R1, R2, R3, and R4 are substituents selected from hydrogen, an alkyl group, an aromatic group, and a group containing any of phosphorus, nitrogen, and sulfur atoms, and R1, R2, R3, and R4 are All of them may be the same or different, and Q ⁻ is an anion in which protons are derived from an inorganic acid or an active hydrogen compound having active hydrogen on an oxygen atom, nitrogen atom or sulfur atom.
2. 2. The method for producing polyarylene sulfide according to 1, wherein the sulfiding agent is an alkali metal sulfide.
3. 3. The method for producing polyarylene sulfide according to either 1 or 2, wherein the organic solvent is an organic amide solvent.
4). The method for producing a polyarylene sulfide according to any one of 1 to 3, wherein the organic phosphorus salt is a quaternary phosphonium salt.
5. 5. The production of polyarylene sulfide according to 4, wherein the organic phosphorus salt represented by the general formula (I) is a quaternary phosphonium salt in which at least one of R1, R2, R3 and R4 is an aromatic group. Method.
6). 4. The method for producing polyarylene sulfide according to any one of 1 to 3, wherein the organic phosphorus salt represented by the general formula (I) is a phosphazenium salt represented by the following general formula (II).

(In the formula, Q ⁻ is an anion in a form in which protons are derived from an inorganic acid or an active hydrogen compound having active hydrogen on an oxygen atom, nitrogen atom or sulfur atom. A, b, c and d are Each is 1 or 0, but all are not simultaneously 0. R may be all the same or different from each other, and each independently represents a hydrocarbon group having 1 to 10 carbon atoms or the same Two Rs on the nitrogen atom may be bonded to each other to form a ring together with the nitrogen atom.)
7). Q ^- is a halogen ion or SH ^- method for producing a polyarylene sulfide according to any one of 1 to 6 is.

  ADVANTAGE OF THE INVENTION According to this invention, the polymerization reaction rate is quick and can provide the method of manufacturing polyarylene sulfide efficiently in a short time.

  The polyarylene sulfide obtained in the present invention is preferably polyphenylene sulfide (hereinafter referred to as PPS resin), and is a polymer having a repeating unit represented by the following structural formula (III).

From the viewpoint of heat resistance, a polymer containing 70 mol% or more, more preferably 90 mol% or more of a polymer containing a repeating unit represented by the above structural formula is preferred. Moreover, about 30 mol% or less of the repeating unit of the PPS resin may be composed of a repeating unit having the following structure.

  Since a PPS copolymer having a part of this structure has a low melting point, a resin composition containing such a PPS copolymer is advantageous in terms of moldability.

  Although there is no restriction | limiting in particular in the melt viscosity of PPS resin obtained by this invention, From the meaning which obtains more excellent mechanical strength, for example, 5 Pa * s (310 degreeC, shear rate 1000 / s) or more is preferable, and 10 Pa * s or more is preferable. Is more preferable. The upper limit is preferably 600 Pa · s or less from the viewpoint of maintaining melt fluidity.

  In addition, the melt viscosity in this invention is the value measured using the Toyo Seiki Co., Ltd. capilograph on the conditions of 310 degreeC and the shear rate of 1000 / s.

  The feature of the present invention is that polyarylene sulfide is polymerized in the presence of an organic phosphorus salt having the structural formula of the following general formula (I).

  Such an organic phosphorus salt is a compound represented by the following structure.

(However, R1, R2, R3, and R4 are substituents selected from hydrogen, an alkyl group, an aromatic group, and a group containing any of phosphorus, nitrogen, and sulfur atoms, and R1, R2, R3, and R4 are All of them may be the same or different, and Q ⁻ is an anion in which protons are derived from an inorganic acid or an active hydrogen compound having active hydrogen on an oxygen atom, nitrogen atom or sulfur atom.

Among the compounds leading to Q ⁻ , examples of the inorganic acid include hydrogen halides such as hydrogen fluoride, hydrogen chloride, hydrogen bromide or hydrogen iodide, hydrogen cyanide, thiocyanic acid or hydrogen azide.

Among the compounds leading to the anion Q ⁻ , the active compound having an active hydrogen atom on the oxygen atom is water; for example, formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, lauric acid, stearic acid, oleic acid, phenylacetic acid. Carboxylic acids having 1 to 20 carbon atoms such as dihydrocinnamic acid, cyclohexanecarboxylic acid, benzoic acid, paramethylbenzoic acid and 2-carboxynaphthalene; for example, succinic acid, malonic acid, succinic acid, maleic acid, fumaric acid, adipic acid, Polyvalent carboxylic acids having 2 to 6 carbon atoms having 2 to 6 carbon atoms such as itaconic acid, butanetetracarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid and pyromellitic acid; , N-diethylcarbamic acid, N-carboxypyrrolidone, N-carboxyl Phosphorus and carbamic acids such as N, N′-dicarboxy-2,4-toluenediamine; for example, methanol, ethanol, normal-propanol, isopropanol, normal-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isopentyl alcohol Tert-pentyl alcohol, normal octyl alcohol, lauryl alcohol, cetyl alcohol, cyclopentanol, cyclohexanol, allyl alcohol, crotyl alcohol, methyl vinyl carbinol, benzyl alcohol, 1-phenylethyl alcohol, triphenyl carbinol and Alcohols having 1 to 20 carbon atoms such as cinnamyl alcohol; for example, ethylene glycol, propylene glycol, diethylene glycol Dipropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanediol, trimethylolpropane, glycerin, diglycerin, pentaerythritol And polyhydric alcohols having 2 to 8 carbon atoms having 2 to 8 carbon atoms such as dipentaerythritol; for example, phenol, o-chlorophenol, m-chlorophenol, p-chlorophenol, 2,4-chlorophenol 2,4,6-chlorophenol, o-bromophenol, m-bromophenol, p-bromophenol, 2,4-bromophenol, 2,4,6-bromophenol, o-iodophenol, m-iodophenol , P-iodophenol, 2,4-iodo And aromatic compounds having 1 to 3 carbon atoms having 6 to 20 carbon atoms such as dophenol, 2,4,6-iodophenol, 2-naphthol, 2,6-dihydroxynaphthalene and bisphenol A. .

Further, among the compounds leading to the anion Q ⁻ , examples of the active compound having an active hydrogen atom on the sulfur atom include the above-described compounds in which the oxygen of the active compound having an active hydrogen atom on the oxygen atom is replaced with sulfur. .

Among them, Q ^- as the anion, chloride ion, fluorine ion, iodine ion, a bromine ion, SH ^- ion, p- chlorothiophenol ions (ClC ₆ H ₅ S ^-) is especially preferred.

  On the other hand, the organic phosphorus cation used in the present invention is represented by the following general formula.

(However, R1, R2, R3, and R4 are substituents selected from hydrogen, an alkyl group, an aromatic group, or a group containing phosphorus, nitrogen, and sulfur atoms, and R1, R2, R3, and R4 are all the same. , May be different.)

  Here, the alkyl group preferably has 1 to 20 carbon atoms, and the aromatic group preferably has 6 to 20 carbon atoms, and may be unsubstituted or substituted.

  Of these, quaternary phosphonium cations and / or phosphazenium cations are particularly suitable. Specific examples of the quaternary phosphonium cation include tetraphenylphosphonium, butyltriphenylphosphonium, dibutyldiphenylphosphonium, ethyltriphenylphosphonium, didiethyldiphenylphosphonium, tetra (n-butyl) phosphonium, tetra (t-butyl) phosphonium, hexa Examples include decyltributylphosphonium, ethyltrioctylphosphonium, ethylenebis [tris (cyanoethyl) phosphonium], and in particular, aromatics such as tetraphenylphosphonium, butyltriphenylphosphonium, dibutyldiphenylphosphonium, ethyltriphenylphosphonium, and didiethyldiphenylphosphonium. A phosphonium cation having a group substituent is particularly useful in that it has excellent heat resistance. Here, the aromatic substituent may be a phenyl group having no substituent, and has a substituent such as an alkyl group, a phenyl group, an amino group, a nitro group, a hydroxyl group, a halo spirit, a carboxyl group, or a carboxylate group. May be.

    Next, the phosphazenium cation is an organophosphorus cation represented by the following general formula. However, the phosphazenium cation is represented by the ultimate structural formula in which the positive charge is localized on the central phosphorus atom (that is, the general formula (II)), but innumerable other extreme structural formulas are drawn. Actually, the positive charge is delocalized as a whole.

(Wherein a, b, c and d are each 1 or 0, but not all are simultaneously 0. R may be the same or different from each other, each independently having 1 to 10 hydrocarbon groups may be represented, or two Rs on the same nitrogen atom may be bonded to each other to form a ring together with the nitrogen atom.)

  In the above general formula, a, b, c and d are each 1 or 0. However, all are not 0 at the same time. Of these, at least three of a, b, c and d are preferably 1. This means that it is a number in the combination of (1, 1, 1, 1) or (0, 1, 1, 1) regardless of the order. More preferably, all of a, b, c and d are 1.

In the above general formula, all Rs may be the same or different from each other. _Two Rs in the notation “R ₂ ” may be different from each other. Each R represents a hydrocarbon group having 1 to 10 carbon atoms, or two Rs on the same nitrogen atom may be bonded to each other to form a ring together with the nitrogen atom.

  When R independently represents a hydrocarbon group, specifically, for example, methyl, ethyl, normal-propyl, isopropyl, allyl, normal-butyl, sec-butyl, tert-butyl, 2-butenyl, 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, isopentyl, tert-pentyl, 3-methyl-2-butyl, neopentyl, normal-hexyl, 4-methyl-2-pentyl, cyclopentyl, cyclohexyl, 1- Heptyl, 3-heptyl, 1-octyl, 2-octyl, 2-ethyl-1-hexyl, 1,1-dimethyl-3,3-dimethylbutyl (common name, tert-octyl), nonyl, decyl, phenyl, 4- Aliphatic or aromatic hydrocarbons such as toluyl, benzyl, 1-phenylethyl and 2-phenylethyl It is selected from the group. Of these, an aliphatic hydrocarbon group having 1 to 10 carbon atoms such as methyl, ethyl, normal-propyl, isopropyl, tert-butyl, tert-pentyl or 1,1-dimethyl-3,3-dimethylbutyl is preferable. A methyl group is more preferable.

  When R is a divalent substituent formed by bonding two Rs to each other on the same nitrogen to form a divalent substituent, the divalent substituent is divalent having a main chain of 4 to 6 carbon atoms. (The ring is a 5- to 7-membered ring containing a nitrogen atom), for example, tetramethylene, pentamethylene, hexamethylene, or the like, or their main chain substituted with an alkyl group such as methyl or ethyl Is preferred. More preferred is tetramethylene or pentamethylene.

  Such a ring structure may be taken for all possible nitrogen atoms in the phosphazenium cation, or a part thereof. In the case where a part of R has a ring structure, examples of the remaining R include the groups exemplified in the case where R represents a hydrocarbon group alone, and preferred groups are also the same.

  These phosphazenium compounds can be synthesized by the method described on pages 12 to 13 of European Patent 0791600B1 or a similar method.

  The amount of the organic phosphorus salt added during polymerization is preferably 0.0001 mol as the lower limit and 5 mol as the upper limit with respect to 1 mol of the sulfidizing agent. When the amount is less than 0.0001 mol, the polymerization promoting effect is remarkably reduced, and even when 5 mol or more is added, the further polymerization promoting effect is not significant. More preferable range of the lower limit is 0.01 mol or more, more preferably 0.1 mol or more, and more preferable range of the upper limit is 2 mol or less, further 1 mol or less, further 0.5 mol or less. Further, the range of 0.2 mol or less, further 0.1 mol or less is particularly useful in view of the polymerization promoting effect. In the present invention, the amount of the sulfidizing agent charged is the residual amount obtained by subtracting the loss from the actual amount charged when a partial loss of the sulfidizing agent occurs before the start of the polymerization reaction due to the dehydration operation described later. Means.

  There is no particular designation as to the timing of addition of these organic phosphorus salts, and they may be added at any time during the start of the pre-process described later, during the pre-process, at the start of the polymerization, or during the polymerization, or divided into multiple times. It may be added.

  Alternatively, the organic phosphorus salt may start polymerization in the state of being present in the system at the start of the polymerization, the organic phosphorus salt may be separated from the reaction solution during the polymerization, and the polymerization may be continued. As a method of separation, a method of separating the organic phosphorus compound by cooling the polymer component once cooled and precipitated in the middle of the polymerization and separating the organic phosphorus compound on the carrier in advance is introduced at the start of polymerization. A method of separating the organic phosphorus salt by transferring the polymerization solution to another reaction tank in the middle and separating it from the organic phosphorus salt-supported carrier, and further the reaction solution continuously under the condition where the organic phosphate salt-supported carrier is installed. By flowing, a method of separating the reaction solution from the reaction solution after contact with the organic phosphorus salt can be exemplified. Examples of the carrier include activated carbon, alumina, silica, barium sulfate, barium carbonate, hydroxyapatite, zeolite, and a layered silicate represented by montmorillonite.

  Next, the contents of the polyhalogen aromatic compound, the sulfidizing agent, the polymerization solvent, the molecular weight regulator, the polymerization aid and the polymerization stabilizer when polymerizing the polyarylene sulfide in the present invention will be described.

[Polyhalogenated aromatic compounds]
The polyhalogenated aromatic compound used in the present invention refers to a compound having two or more halogen atoms in one molecule. Specific examples include p-dichlorobenzene, m-dichlorobenzene, o-dichlorobenzene, 1,3,5-trichlorobenzene, 1,2,4-trichlorobenzene, 1,2,4,5-tetrachlorobenzene, hexa Polyhalogenated aromatics such as chlorobenzene, 2,5-dichlorotoluene, 2,5-dichloro-p-xylene, 1,4-dibromobenzene, 1,4-diiodobenzene, 1-methoxy-2,5-dichlorobenzene Group compounds, and preferably p-dichlorobenzene is used. Further, it is possible to combine two or more different polyhalogenated aromatic compounds into a copolymer, but it is preferable to use a p-dihalogenated aromatic compound as a main component.

  The amount of the polyhalogenated aromatic compound used is 0.9 to 2.0 mol, preferably 0.95 to 1.5 mol, per mol of the sulfidizing agent, from the viewpoint of obtaining a PPS resin having a viscosity suitable for processing. More preferably, the range of 1.005 to 1.2 mol can be exemplified.

[Sulfiding agent]
Examples of the sulfidizing agent used in the present invention include alkali metal sulfides, alkali metal hydrosulfides, and hydrogen sulfide.

  Specific examples of the alkali metal sulfide include lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, cesium sulfide and a mixture of two or more of these, and sodium sulfide is preferably used. These alkali metal sulfides can be used as hydrates or aqueous mixtures or in the form of anhydrides.

  Specific examples of the alkali metal hydrosulfide include, for example, sodium hydrosulfide, potassium hydrosulfide, lithium hydrosulfide, rubidium hydrosulfide, cesium hydrosulfide and a mixture of two or more of these. Preferably used. These alkali metal hydrosulfides can be used as hydrates or aqueous mixtures or in the form of anhydrides.

  A sulfidizing agent prepared in situ in a reaction system from an alkali metal hydrosulfide and an alkali metal hydroxide can also be used. Further, a sulfidizing agent can be prepared from alkali metal hydrosulfide and alkali metal hydroxide, and transferred to a polymerization tank for use.

  Alternatively, a sulfidizing agent prepared in situ in a reaction system from an alkali metal hydroxide such as lithium hydroxide or sodium hydroxide and hydrogen sulfide can also be used. Further, a sulfidizing agent can be prepared from alkali metal hydroxides such as lithium hydroxide and sodium hydroxide and hydrogen sulfide, and transferred to a polymerization tank for use.

  In the present invention, the amount of the sulfidizing agent charged means the residual amount obtained by subtracting the loss from the actual charged amount when a partial loss of the sulfiding agent occurs before the start of the polymerization reaction due to dehydration operation or the like. Shall.

  An alkali metal hydroxide and / or an alkaline earth metal hydroxide can be used in combination with the sulfidizing agent. Specific examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide, lithium hydroxide, rubidium hydroxide, cesium hydroxide, and a mixture of two or more thereof. Specific examples of the metal hydroxide include, for example, calcium hydroxide, strontium hydroxide, barium hydroxide, and sodium hydroxide is preferably used.

  When an alkali metal hydrosulfide is used as the sulfiding agent, it is particularly preferable to use an alkali metal hydroxide at the same time, but the amount used is 0.95 to 1. A range of 20 mol, preferably 1.00 to 1.15 mol, more preferably 1.005 to 1.100 mol can be exemplified.

[Polymerization solvent]
In the present invention, an organic polar solvent is preferably used as the polymerization solvent. Specific examples include N-alkylpyrrolidones such as N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone, caprolactams such as N-methyl-ε-caprolactam, and 1,3-dimethyl-2-imidazolide. Non-, N, N-dimethylacetamide, N, N-dimethylformamide, hexamethylphosphoric acid triamide, dimethyl sulfone, tetramethylene sulfoxide and the like, and mixtures thereof, and the like are all included. It is preferably used because of its high reaction stability. Of these, N-methyl-2-pyrrolidone (hereinafter sometimes abbreviated as NMP) is particularly preferably used.

  The amount of the organic polar solvent used is selected in the range of 2.0 to 10 mol, preferably 2.25 to 6.0 mol, more preferably 2.5 to 5.5 mol per mol of the sulfidizing agent. .

[Molecular weight regulator]
In the present invention, a monohalogen compound (not necessarily an aromatic compound) is converted to the polyhalogenated compound in order to form a terminal end of the pre-treatment PPS resin to be produced or to adjust a polymerization reaction or a molecular weight. It can be used in combination with an aromatic compound.

[Polymerization aid]
In the present invention, in order to obtain a pre-treatment PPS resin having a relatively high degree of polymerization in a shorter time, it is one of preferred embodiments to use a polymerization aid. Here, the polymerization assistant means a substance having an action of increasing the viscosity of the obtained polyarylene sulfide resin. Specific examples of such polymerization aids include, for example, organic carboxylates, water, alkali metal chlorides, organic sulfonates, alkali metal sulfates, alkaline earth metal oxides, alkali metal phosphates and alkaline earths. Metal phosphates and the like. These may be used alone or in combination of two or more. Of these, organic carboxylates and / or water are preferably used.

  The alkali metal carboxylate is a general formula R (COOM) n (wherein R is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, an aryl group, an alkylaryl group, or an arylalkyl group). M is an alkali metal selected from lithium, sodium, potassium, rubidium and cesium, and n is an integer of 1 to 3). Alkali metal carboxylates can also be used as hydrates, anhydrides or aqueous solutions. Specific examples of the alkali metal carboxylate include, for example, lithium acetate, sodium acetate, potassium acetate, sodium propionate, lithium valerate, sodium benzoate, sodium phenylacetate, potassium p-toluate, and mixtures thereof. Can be mentioned.

  The alkali metal carboxylate is an organic acid and one or more compounds selected from the group consisting of alkali metal hydroxides, alkali metal carbonates, and alkali metal bicarbonates, and are allowed to react by adding approximately equal chemical equivalents. You may form by. Among the alkali metal carboxylates, lithium salts are highly soluble in the reaction system and have a large auxiliary effect, but are expensive, and potassium, rubidium and cesium salts are insufficiently soluble in the reaction system. Therefore, sodium acetate, which is inexpensive and has an appropriate solubility in the polymerization system, is most preferably used.

  The amount used in the case of using these polymerization aids is usually in the range of 0.01 mol to 0.7 mol with respect to 1 mol of the charged alkali metal sulfide, and 0.1 to 0.1 in terms of obtaining a higher degree of polymerization. The range of 0.6 mol is preferable, and the range of 0.2 to 0.5 mol is more preferable.

  The use of water as a polymerization aid is one of the effective means for obtaining a resin composition in which fluidity and high toughness are highly balanced. In that case, the addition amount is usually in the range of 0.5 mol to 15 mol with respect to 1 mol of the charged alkali metal sulfide, and in the sense of obtaining a higher degree of polymerization, the range of 0.6 to 10 mol is preferable. The range of 1-5 mol is more preferable.

  There is no particular designation as to the timing of addition of these polymerization aids, which may be added at any time during the previous step, polymerization start, polymerization in the middle to be described later, or may be added in multiple times. When using an alkali metal carboxylate as a polymerization aid, it is more preferable to add it at the start of the previous step or at the start of the polymerization from the viewpoint of easy addition. When water is used as a polymerization aid, it is effective to add the polyhalogenated aromatic compound during the polymerization reaction after charging.

[Polymerization stabilizer]
In the present invention, a polymerization stabilizer may be used to stabilize the polymerization reaction system and prevent side reactions. The polymerization stabilizer contributes to stabilization of the polymerization reaction system and suppresses undesirable side reactions. One measure of the side reaction is the generation of thiophenol, and the addition of a polymerization stabilizer can suppress the generation of thiophenol. Specific examples of the polymerization stabilizer include compounds such as alkali metal hydroxides, alkali metal carbonates, alkaline earth metal hydroxides, and alkaline earth metal carbonates. Among these, alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide are preferable. Since the alkali metal carboxylate described above also acts as a polymerization stabilizer, it is one of the polymerization stabilizers used in the present invention. In addition, when an alkali metal hydrosulfide is used as a sulfidizing agent, it has been described above that it is particularly preferable to use an alkali metal hydroxide at the same time. Oxides can also be polymerization stabilizers.

  These polymerization stabilizers can be used alone or in combination of two or more. The polymerization stabilizer is usually in a proportion of 0.02 to 0.2 mol, preferably 0.03 to 0.1 mol, more preferably 0.04 to 0.09 mol, relative to 1 mol of the charged alkali metal sulfide. Is preferably used. If this ratio is small, the stabilizing effect is insufficient. Conversely, if it is too much, it is economically disadvantageous and the polymer yield tends to decrease.

  The addition timing of the polymerization stabilizer is not particularly specified, and may be added at any time during the previous step, at the start of polymerization, or during the polymerization described later, or may be added in multiple times. It is more preferable to add at the start of the process or at the start of the polymerization from the viewpoint of easy addition.

  Next, the method for producing a pre-treatment PPS resin of the present invention will be described in detail in order, including a pre-process, a polymerization reaction process, a recovery process, and a post-treatment process, but of course, the process is not limited to this method. However, the present technology can be applied to various methods such as batch polymerization or continuous polymerization.

[pre-process]
In the method for producing polyarylene sulfide of the present invention, the sulfiding agent is usually used in the form of a hydrate. Before adding the polyhalogenated aromatic compound, the mixture containing the organic polar solvent and the sulfiding agent is added. It is preferable to raise the temperature and remove excess water out of the system. In addition, when water is removed excessively by this operation, it is preferable to add and replenish the deficient water.

  Further, as described above, an alkali metal sulfide prepared from an alkali metal hydrosulfide and an alkali metal hydroxide in situ in the reaction system or in a tank different from the polymerization tank is also used as the sulfidizing agent. be able to. Although there is no particular limitation on this method, desirably an alkali metal hydrosulfide and an alkali metal hydroxide are added to the organic polar solvent in an inert gas atmosphere at a temperature ranging from room temperature to 150 ° C., preferably from room temperature to 100 ° C. In addition, there is a method in which the temperature is raised to at least 150 ° C. or more, preferably 180 to 260 ° C. under normal pressure or reduced pressure, and water is distilled off. A polymerization aid may be added at this stage. Moreover, in order to accelerate | stimulate distillation of a water | moisture content, you may react by adding toluene etc.

  Further, after distilling water, the distilling is further continued, and the amount of water in the system and the amount of organic amide solvent are adjusted to 0.05 mol or more and less than 0.8 mol, respectively, per 1 mol of sulfur component. Can also be used in the polymerization.

  The amount of water in the polymerization system in the polymerization reaction is preferably 0.5 to 10.0 moles per mole of the charged sulfidizing agent. Here, the amount of water in the polymerization system is an amount obtained by subtracting the amount of water removed from the polymerization system from the amount of water charged in the polymerization system. In addition, the water to be charged may be in any form such as water, an aqueous solution, and crystal water.

[Polymerization reaction step]
In the present invention, it is preferable to produce polyarylene sulfide by reacting a sulfidizing agent with a polyhalogenated aromatic compound in an organic polar solvent within a temperature range of 200 ° C. or higher and lower than 290 ° C.

  When starting the polymerization reaction step, the sulfidizing agent and the polyhalogenated aromatic compound are added to the organic polar solvent in an inert gas atmosphere at a temperature ranging from room temperature to 220 ° C, preferably 100 to 220 ° C. A polymerization aid may be added at this stage. The order in which these raw materials are charged may be out of order or may be simultaneous.

  The mixture is usually heated to a temperature in the range of 200 ° C to 290 ° C. Although there is no restriction | limiting in particular in a temperature increase rate, Usually, the speed of 0.01-5 degreeC / min is selected, and the range of 0.1-3 degreeC / min is more preferable.

  In general, the temperature is finally raised to a temperature of 230 to 290 ° C., and the reaction is usually carried out at that temperature for 0.05 to 50 hours, preferably 0.5 to 20 hours.

  In the stage before reaching the final temperature, for example, a method of reacting at 200 to 260 ° C. for a certain time and then raising the temperature to 270 to 290 ° C. is effective in obtaining a higher degree of polymerization. Under the present circumstances, as reaction time in 200 to 260 degreeC, the range of 0.25 to 20 hours is normally selected, Preferably the range of 0.25 to 10 hours is selected.

  In order to obtain a polymer having a higher degree of polymerization, it is effective to perform polymerization in a plurality of stages. When the polymerization is performed in a plurality of stages, it is effective that the conversion of the polyhalogenated aromatic compound in the system at 245 ° C. reaches 40 mol% or more, preferably 60 mol%.

  The conversion rate of the polyhalogenated aromatic compound (herein abbreviated as PHA) is a value calculated by the following formula. The residual amount of PHA can usually be determined by gas chromatography.

(A) When polyhalogenated aromatic compound is added excessively in a molar ratio with respect to the alkali metal sulfide Conversion rate = [PHA charge (mol) −PHA remaining amount (mol)] / [PHA charge (mol) -PHA excess (mole)]

(B) In cases other than the above (a) Conversion rate = [PHA charge (mol) −PHA remaining amount (mol)] / [PHA charge (mol)]

[Recovery process]
In the method for producing polyarylene sulfide of the present invention, after the polymerization is completed, a solid is recovered from a polymerization reaction product containing a polymer, a solvent, and the like.

The most preferable method for recovering the polyarylene sulfide of the present invention is a method for evaporating the polymerization solvent. One preferable method of this recovery method is a flash method. The flash method is a method in which a polymerization reaction product is flushed from a high-temperature and high-pressure (usually 200 ° C. or higher, 2 kg / cm ² or higher) state to an atmosphere of normal pressure or reduced pressure, and simultaneously with solvent recovery, the polymer is made into a granular form. This is a recovery method, and the term “flush” here means that a polymerization reaction product is ejected from a nozzle. Specific examples of the atmosphere to be flushed include nitrogen or water vapor at normal pressure, and the temperature is usually selected from the range of 150 ° C to 250 ° C.

  The flash method is a recovery method that is excellent in economic efficiency because it can recover the solids simultaneously with the recovery of the solvent and the recovery time can be relatively short. In this recovery method, an ionic compound typified by Na or an organic low-polymerization product (oligomer) tends to be easily taken into the polymer during the solidification process.

  However, the recovery method of the present invention is not limited to the flash method. Of course, it is possible to use a method (quenching method) of slowly cooling and recovering the particulate polymer as long as it satisfies the requirements of the present invention.

[Post-processing process]
The polyarylene sulfide obtained in the present invention may be produced through the above polymerization and recovery steps, and then subjected to acid treatment, carboxylic acid metal salt treatment, hot water treatment, or washing with an organic solvent.

  When acid treatment is performed, it is as follows. The acid used for the acid treatment of polyarylene sulfide in the present invention is not particularly limited as long as it does not have an action of decomposing polyarylene sulfide, and examples thereof include acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, silicic acid, carbonic acid, and propyl acid. Among them, acetic acid and hydrochloric acid are more preferably used, but those that decompose and deteriorate polyarylene sulfide such as nitric acid are not preferable.

  As the acid treatment method, there is a method of immersing the PPS resin in an acid or an acid aqueous solution, and it is possible to appropriately stir or heat as necessary. For example, when acetic acid is used, a sufficient effect can be obtained by immersing polyarylene sulfide in an aqueous solution of pH 4 heated to 80 to 200 ° C. and stirring for 30 minutes. The pH after the treatment may be 4 or more, for example, about pH 4-8. The polyarylene sulfide subjected to the acid treatment is preferably washed several times with water or warm water in order to remove residual acid or salt. The water used for washing is preferably distilled water or deionized water in the sense that it does not impair the preferable chemical modification effect of polyarylene sulfide by acid treatment.

  The carboxylic acid metal salt aqueous solution treatment method includes (A) a method of impregnating polyarylene sulfide in the same manner as the acid treatment described above. Specific examples of the carboxylic acid metal salt used include lithium acetate, sodium acetate, and acetic acid. Potassium, calcium acetate, magnesium acetate, barium acetate, lithium propionate, sodium propionate, potassium propionate, sodium propionate, magnesium propionate, barium propionate, lithium 2-methylpropionate, rubidium butyrate, lithium valerate, Sodium valerate, potassium valerate, calcium valerate, magnesium valerate, barium valerate, cesium hexanoate, lithium heptanoate, lithium 2-methyloctanoate, potassium dodecanoate, rubizi 4-ethylethradecanoate , Sodium octadecanoate, sodium heneicoate, lithium cyclohexanecarboxylate, calcium cyclohexanecarboxylate, magnesium cyclohexanecarboxylate, cesium cyclododecanecarboxylate, cesium 3-methylcyclopentanecarboxylate, potassium chlorohexyl acetate, calcium chlorohexyl acetate, siloxyhexyl acetate Magnesium, potassium benzoate, calcium benzoate, magnesium benzoate, barium benzoate, aluminum benzoate, potassium m-toluate, lithium phenylacetate, calcium phenylacetate, magnesium phenylacetate, sodium 4-phenylcyclohexanecarboxylate, 4- Calcium phenylcyclohexanecarboxylate, 4-phenylcyclohexanecarboxylic acid magne , Potassium p-tolylacetate, calcium p-tolylacetate, magnesium p-tolylacetate, lithium 4-ethylcyclohexylacetate, calcium 4-ethylcyclohexylacetate, magnesium 4-ethylcyclohexylacetate, and other similar salts, and their A mixture etc. are mentioned, Sodium acetate, calcium acetate, and magnesium acetate are preferable. Preferred conditions for the treatment temperature, time, and number of washings include the same conditions as in the acid treatment described above.

  When performing hot water treatment, it is as follows. In the hydrothermal treatment of the polyarylene sulfide obtained in the present invention, the temperature of the hot water is preferably 100 ° C. or higher, more preferably 120 ° C. or higher, further preferably 150 ° C. or higher, and particularly preferably 170 ° C. or higher. . It is preferable to perform the hydrothermal treatment in such a temperature range because a preferable chemical modification effect of polyarylene sulfide can be obtained.

  The water used is preferably distilled water or deionized water in order to express the preferable chemical modification effect of the polyarylene sulfide by the hot water washing of the present invention. There are no particular restrictions on the operation of the hot water treatment, and a predetermined amount of polyarylene sulfide is charged into a predetermined amount of water and heated and stirred in a pressure vessel, or a continuous hydrothermal treatment method is performed. The ratio of polyarylene sulfide to water is preferably larger, but usually a bath ratio of 200 g or less of polyarylene sulfide is selected with respect to water 1.

  Further, since the decomposition of the terminal group is not preferable, the treatment atmosphere is preferably an inert atmosphere in order to avoid this. Further, the polyarylene sulfide after the hydrothermal treatment operation is preferably washed several times with warm water in order to remove remaining components.

  When washing with an organic solvent, it is as follows. The organic solvent used for washing the polyarylene sulfide obtained in the present invention is not particularly limited as long as it does not have an action of decomposing polyarylene sulfide. For example, N-methyl-2-pyrrolidone, dimethylformamide, dimethyl Nitrogen-containing polar solvents such as acetamide, 1,3-dimethylimidazolidinone, hexamethylphosphoramide, piperazinones, sulfoxide / sulfon solvents such as dimethyl sulfoxide, dimethyl sulfone, sulfolane, acetone, methyl ethyl ketone, diethyl ketone, acetophenone, etc. Ketone solvents, ether solvents such as dimethyl ether, dipropyl ether, dioxane, tetrahydrofuran, chloroform, methylene chloride, trichloroethylene, ethylene dichloride, perchlorethylene, Halogen solvents such as chloroethane, dichloroethane, tetrachloroethane, perchlorethane, chlorobenzene, alcohols such as methanol, ethanol, propanol, butanol, pentanol, ethylene glycol, propylene glycol, phenol, cresol, polyethylene glycol, polypropylene glycol Examples thereof include phenol solvents and aromatic hydrocarbon solvents such as benzene, toluene and xylene. Among these organic solvents, use of N-methyl-2-pyrrolidone, acetone, dimethylformamide, chloroform and the like is particularly preferable, and these organic solvents are used alone or in combination of two or more.

  As a method of washing with an organic solvent, there is a method of immersing polyarylene sulfide in an organic solvent, and if necessary, stirring or heating can be appropriately performed. There is no restriction | limiting in particular about the washing | cleaning temperature at the time of wash | cleaning polyarylene sulfide with an organic solvent, Arbitrary temperature of about normal temperature-about 300 degreeC can be selected. Although the cleaning efficiency tends to increase as the cleaning temperature increases, a sufficient effect is usually obtained at a cleaning temperature of room temperature to 150 ° C. It is also possible to wash under pressure in a pressure vessel at a temperature above the boiling point of the organic solvent. There is no particular limitation on the cleaning time. Depending on the cleaning conditions, in the case of batch-type cleaning, a sufficient effect can be obtained usually by cleaning for 5 minutes or more. It is also possible to wash in a continuous manner.

  These acid treatment, hot water treatment or washing with an organic solvent can be carried out by appropriately combining them.

Pre-treatment PPS resin obtained by the above production method can be subjected to thermal oxidation treatment by heating in an oxygen atmosphere or by adding a peroxide such as H ₂ O ₂ or a vulcanizing agent such as S. It is. A thermal oxidation treatment method by heating in an oxygen atmosphere is particularly preferred because of the simplicity of the treatment.

  The heating device for the thermal oxidation treatment may be a normal hot air dryer or a heating device with a rotary type or a stirring blade. However, for efficient and more uniform processing, a rotary type or a stirring blade is used. It is more preferable to use the heating device. The oxygen concentration during the thermal oxidation treatment is preferably 2% by volume or more, and more preferably 8% by volume or more. Although there is no restriction | limiting in particular in the upper limit of oxygen concentration, About 50 volume% is a limit and 25 volume% or less is more preferable. Preferred temperature conditions for the thermal oxidation treatment are as described above. Treatment time includes 0.5 to 50 hours, more preferably 0.5 to 20 hours, and further preferably 0.5 to 10 hours.

  Further, before and after the thermal oxidation treatment, it is possible to suppress thermal oxidation cross-linking and perform a dry heat treatment for the purpose of removing volatile components and moisture. The temperature is preferably 130 to 250 ° C, and more preferably 160 to 250 ° C. In this case, the oxygen concentration is preferably less than 2% by volume. The treatment time is preferably 0.5 to 50 hours, more preferably 1 to 20 hours, and further preferably 1 to 10 hours. The heat treatment apparatus may be a normal hot air dryer or a heating apparatus with a rotary blade or a stirring blade. However, for efficient and more uniform treatment, a heating device with a rotary blade or a stirring blade is used. Is more preferable.

  The polyarylene sulfide of the present invention thus obtained is excellent in heat resistance, chemical resistance, flame retardancy, electrical properties and mechanical properties, and is suitably applied particularly to injection molding applications.

  In addition, it is also possible to add other resin to the polyarylene sulfide obtained by the present invention within a range not impairing the effects of the present invention. For example, the flexibility and impact resistance can be further improved by adding a small amount of a highly flexible thermoplastic resin. However, if this amount exceeds 50% by weight of the total composition, the original characteristics of the PPS resin are impaired, and in particular, addition of 30% by weight or less is preferably used. Specific examples of thermoplastic resins include epoxy group-containing olefin copolymers, acid anhydride group-containing olefin copolymers and other olefin resins, polyamide resins, polybutylene terephthalate resins, polyethylene terephthalate resins, polyphenylene ether resins, Polysulfone resin, polyallylsulfone resin, polyketone resin, polyetherimide resin, polyarylate resin, liquid crystal polymer, polyethersulfone resin, polyetherketone resin, polythioetherketone resin, polyetheretherketone resin, polyimide resin, polyamide Examples thereof include imide resins and tetrafluoropolyethylene resins.

  Moreover, the following compounds can be added for the purpose of modification. Coupling agents such as isocyanate compounds, organosilane compounds, organotitanate compounds, organoborane compounds, epoxy compounds, polyalkylene oxide oligomer compounds, thioether compounds, ester compounds, organophosphorus compounds, etc. , Talc, kaolin, organophosphorus compounds, crystal nucleating agents such as polyetheretherketone, montanic acid waxes, metal soaps such as lithium stearate and aluminum stearate, ethylenediamine / stearic acid / sebacic acid polycondensates, silicone compounds Other additives such as mold release agents such as hypophosphites, lubricants, UV inhibitors, colorants, foaming agents and the like can be blended. If any of the above compounds exceeds 20% by weight of the total composition, the original properties of the PPS resin are impaired, and therefore it is not preferred, and 10% by weight or less, more preferably 1% by weight or less is added.

  The polyarylene sulfide obtained in the present invention has at least one selected from an epoxy group, an amino group, an isocyanate group, a hydroxyl group, a mercapto group, and a ureido group for the purpose of improving mechanical strength, toughness and the like. You may add the alkoxysilane which has the functional group of. Specific examples of such compounds include epoxy group-containing alkoxysilanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. Compounds, mercapto group-containing alkoxysilane compounds such as γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, γ-ureidopropyltrimethoxysilane, γ- (2-ureidoethyl) ) Ureido group-containing alkoxysilane compounds such as aminopropyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropyltrimethoxysilane, γ-isocyanatopropylmethyldimethoxysilane, Isocyanato group-containing alkoxysilane compounds such as γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropylethyldimethoxysilane, γ-isocyanatopropylethyldiethoxysilane, γ-isocyanatopropyltrichlorosilane, γ- (2- Amino group-containing alkoxysilane compounds such as aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, and γ-hydroxypropyltrimethoxysilane, γ- Examples thereof include a hydroxyl group-containing alkoxysilane compound such as hydroxypropyltriethoxysilane.

  A suitable addition amount of such a silane compound is selected in a range of 0.05 to 5 parts by weight with respect to 100 parts by weight of polyarylene sulfide.

  The polyarylene sulfide obtained in the present invention can be used by blending a filler as long as the effects of the present invention are not impaired. Specific examples of such fillers include glass fiber, carbon fiber, basalt fiber, potassium titanate whisker, zinc oxide whisker, calcium carbonate whisker, wollastonite whisker, aluminum borate whisker, aramid fiber, alumina fiber, silicon carbide fiber, ceramic fiber. , Fibrous fillers such as asbestos fiber, stone fiber, metal fibers, or silicates such as talc, wollastonite, zeolite, sericite, mica, kaolin, clay, pyrophyllite, bentonite, asbestos, alumina silicate, oxidation Metal compounds such as silicon, magnesium oxide, alumina, zirconium oxide, titanium oxide and iron oxide, carbonates such as calcium carbonate, magnesium carbonate and dolomite, sulfates such as calcium sulfate and barium sulfate, calcium hydroxide Non-fibrous fillers such as hydroxides such as magnesium hydroxide and aluminum hydroxide, glass beads, glass flakes, glass powder, ceramic beads, carbon nanotubes, fullerene, boron nitride, silicon carbide, carbon black and silica, graphite These may be hollow, and two or more of these fillers may be used in combination. These fillers may be used after pretreatment with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound, and an epoxy compound.

  The amount of the inorganic filler is usually preferably in the range of 0.0001 to 500 parts by weight and more preferably in the range of 0.001 to 400 parts by weight with respect to 100 parts by weight of the polyarylene sulfide. The content of the inorganic filler can be appropriately changed depending on the application from the balance of strength, rigidity, and other characteristics.

  The kneading machine is a method of kneading at a processing temperature of the melting peak temperature of the PPS resin +5 to 60 ° C. by supplying it to a generally known melt kneader such as a single-screw, twin-screw extruder, Banbury mixer, kneader, and mixing roll. Can be cited as a representative example. When using the auxiliary materials, the mixing order of the raw materials is not particularly limited, and a method in which all raw materials are blended and then melt-kneaded by the above method, a part of the raw materials are blended and then melt-kneaded by the above method, and the remaining raw materials Any method may be used, such as a method of blending and melt-kneading a mixture of materials, or a method of mixing the remaining raw materials using a side feeder during melt-kneading with a single-screw or twin-screw extruder after blending some raw materials. Good. As for the small amount additive component, other components can be kneaded by the above-mentioned method and pelletized, then added before molding and used for molding.

  The polyarylene sulfide obtained in the present invention can be applied to injection molded articles, films, sheets, fibers and the like.

  The polyarylene sulfide resin (composition) thus obtained is particularly suitable for injection molding applications. Specific examples of such applications include sensors, LED lamps, connectors, sockets, resistors, relay cases, switches, Coil bobbin, condenser, variable capacitor case, optical pickup, oscillator, various terminal boards, transformer, plug, printed circuit board, tuner, speaker, microphone, headphones, small motor, magnetic head base, power module, semiconductor, liquid crystal, FDD carriage, Electrical / electronic parts such as FDD chassis, motor brush holder, parabolic antenna, computer-related parts; VTR parts, TV parts, irons, hair dryers, rice cooker parts, microwave oven parts, acoustic parts, audio Audio equipment parts such as laser discs and compact discs, lighting parts, refrigerator parts, air conditioner parts, typewriter parts, word processor parts, household electrical appliance parts, office computer-related parts, telephone-related parts, facsimile-related Machine-related parts such as parts, copier-related parts, cleaning jigs, motor parts, lighters, typewriters, etc .: Optical equipment such as microscopes, binoculars, cameras, watches, precision machine-related parts; Tops, mixing faucets, pump parts, pipe joints, water flow control valves, relief valves, hot water temperature sensors, water volume sensors, water meter housings, and other water-related parts; valve alternator terminals, alternator connectors, IC regulators, light deer potions Ome -Various valves such as base and exhaust gas valves, various pipes related to fuel, exhaust system and intake system, air intake nozzle snorkel, intake manifold, fuel pump, engine coolant joint, carburetor main body, carburetor spacer, exhaust gas sensor, coolant sensor Oil temperature sensor, throttle position sensor, crankshaft position sensor, air flow meter, brake pad wear sensor, thermostat base for air conditioner, heating hot air flow control valve, brush holder for radiator motor, water pump impeller, turbine vane, wiper motor Related parts, distributor, starter switch, starter relay, transmission wire harness, Window washer nozzle, air conditioner panel switch board, fuel-related electromagnetic valve coil, fuse connector, horn terminal, electrical component insulation plate, step motor rotor, lamp socket, lamp reflector, lamp housing, brake piston, solenoid bobbin, engine oil filter Automobile / vehicle-related parts such as ignition device case, vehicle speed sensor, cable liner, engine control unit case, engine driver unit case, condenser case, motor insulation material, hybrid car control system case, and other various applications .

  The present invention will be described more specifically with reference to the following examples.

<Reaction rate of monomer (p-dichlorobenzene)>
The unreacted monomer (p-dichlorobenzene) remaining in the polymerization system was quantified by gas chromatography analysis, and the p-dichlorobenzene reaction rate was calculated based on the following formula.
Reaction rate (%) = (1− (X−Z) / (Y−Z)) × 100
X: Number of moles of residual unreacted p-dichlorobenzene Y: Number of moles of p-dichlorobenzene at the time of charging Z: Number of moles of excess p-dichlorobenzene with respect to the sulfur source at the time of charging It shows that.

<GPC measurement>
In order to measure the weight average molecular weight (Mw) of the polymer, the polymer was prepared to be 0.1% by weight with respect to 1-chloronaphthalene and dissolved at 250 ° C., and then the sample solution was subjected to gel permeation chromatography. (GPC) and calculated in terms of polystyrene. The measurement conditions for GPC are shown below.
Apparatus: SSC-7100 (Senshu Science)
Column name: GPC3506 (Senshu Science)
Eluent: 1-chloronaphthalene detector: differential refractive index detector Column temperature: 210 ° C
Pre-constant temperature: 250 ° C
Pump bath temperature: 50 ° C
Detector temperature: 210 ° C
Flow rate: 1.0 mL / min
Sample injection amount: 300 μL (slurry: about 0.1% by weight)

[Example 1]
In a 1 liter autoclave with a stirrer made of SUS316, 116.9 g of a sodium hydrosulfide aqueous solution with a concentration of 48 wt% (1.0 mol in terms of sodium hydrosulfide) and a purity of 96 wt. An aqueous sodium oxide solution 86.6 g (1.04 mol in terms of sodium hydroxide), NMP 163.6 g (1.65 mol), anhydrous sodium acetate 27.1 g (0.33 mol), and ion-exchanged water 30 g were charged at room temperature. It is. While stirring through nitrogen at normal pressure, the temperature was gradually raised to 240 ° C. over about 3 hours, and 136.3 g of water was distilled. Thereafter, the mixture was cooled to 160 ° C., and 149.2 g (1.04 mol) of p-dichlorobenzene, 37.5 g of tetraphenylphosphonium chloride (0.1 mol; manufactured by Aldrich), and 133.8 g (1.35 mol) of NMP were added. And sealed under nitrogen gas. Thereafter, the temperature was raised to 210 ° C., held for 120 minutes, then cooled to 50 ° C., and the reaction product was recovered.

  The residual p-dichlorobenzene in the contents was quantified to calculate the monomer (p-dichlorobenzene) reaction rate, which was 70%.

  The reaction product recovered after the polymerization was washed four times with 70 ° C. ion exchange water having a bath ratio of 10, and the obtained wet cake was dried at 120 ° C. for 3 hours to obtain a dry PPS. Mw of the obtained PPS was 10,000.

[Example 2]
Instead of tetraphenylphosphonium chloride, tetrakis [tris (dimethylamino) phosphoranylideneamino] phosphonium chloride: [(Me ₂ N) ₃ P═N] ₄ P ⁺ , Cl ⁻ 38.8 g (0.05) The same operation as in Example 1 was performed except that Mol; manufactured by Fluka) was used.

  The reaction rate of the monomer (p-dichlorobenzene) was 87%.

  Further, the Mw of PPS obtained by washing and drying in the same manner as in Example 1 was 14000.

[Comparative Example 1]
Polymerization was performed in the same manner as in Example 1 except that tetraphenylphosphonium chloride was not added, and the reaction product was recovered.

The reaction rate of the monomer (p-dichlorobenzene) was 58%.
Further, the Mw of PPS obtained by washing and drying in the same manner as in Example 1 was 5600.

  In Examples 1 and 2, the monomer reaction rate was higher than that in Comparative Example 1 in which no organic phosphorus salt was added. Moreover, the molecular weights of Examples 1 and 2 are also higher than those of Comparative Example 1, indicating that the polymerization is promoted.

Claims (7)

A method for producing polyarylene sulfide, comprising reacting a sulfidizing agent and a polyhalogenated aromatic compound in an organic solvent in the presence of an organic phosphorus salt represented by the following general formula (I).

(However, R1, R2, R3, and R4 are substituents selected from hydrogen, an alkyl group, an aromatic group, and a group containing any of phosphorus, nitrogen, and sulfur atoms, and R1, R2, R3, and R4 are All of them may be the same or different, and Q ⁻ is an anion in which protons are derived from an inorganic acid or an active hydrogen compound having active hydrogen on an oxygen atom, nitrogen atom or sulfur atom. The method for producing polyarylene sulfide according to claim 1, wherein the sulfiding agent is an alkali metal sulfide. The method for producing polyarylene sulfide according to claim 1, wherein the organic solvent is an organic amide solvent. The method for producing a polyarylene sulfide according to any one of claims 1 to 3, wherein the organic phosphorus salt is a quaternary phosphonium salt. 5. The polyarylene sulfide according to claim 4, wherein the organic phosphorus salt represented by the general formula (I) is a quaternary phosphonium salt in which at least one of R1, R2, R3, and R4 is an aromatic group. Manufacturing method. The method for producing a polyarylene sulfide according to any one of claims 1 to 3, wherein the organic phosphorus salt represented by the general formula (I) is a phosphazenium salt represented by the following general formula (II).

(In the formula, Q ⁻ is an anion in a form in which protons are derived from an inorganic acid or an active hydrogen compound having active hydrogen on an oxygen atom, nitrogen atom or sulfur atom. A, b, c and d are Each is 1 or 0, but all are not simultaneously 0. R may be all the same or different from each other, and each independently represents a hydrocarbon group having 1 to 10 carbon atoms or the same Two Rs on the nitrogen atom may be bonded to each other to form a ring together with the nitrogen atom.) Q ^- is a halogen ion or SH ^- method for producing a polyarylene sulfide according to any one of the is claims 1-6.