JP2016204590A - Manufacturing method of polyarylene sulfide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide polyarylene sulfide having reduced crystallization temperature and solidification temperature and less in gas generation amount during heating, of which achievements are difficult with conventional technologies.SOLUTION: There is provided a method of manufacturing polyarylene sulfide (c) by heating cyclic polyarylene sulfide (a) in the presence of a sulfide compound (b) represented by the formula (B1) or (B2) of 0.1 to 10 mol% based on a sulfur atom in the cyclic polyarylene sulfide. (B1) (B2), where X and Y are O, S, COor SO, M is an alkali earth metal, Z is a C1 to 3 carboxyl group and l and m are integers of 0 or 1.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a polyarylene sulfide excellent in molding processability in which a crystallization temperature is lowered and a solidification rate is suppressed.

  In recent years, organic sulfur compounds (such as thiols, thioketones, thioethers, and thioacids) have attracted attention due to their unique properties and are used in medicines, agricultural chemicals, industrial chemicals, and the like. In addition, a large number of aromatic polymer compounds (polyarylene sulfide, hereinafter sometimes abbreviated as PAS) having sulfur as a bond are also produced. PAS typified by polyphenylene sulfide (hereinafter sometimes abbreviated as PPS) is a resin having properties suitable as engineering plastics, such as heat resistance, barrier properties, chemical resistance, electrical insulation properties, moist heat resistance, and flame resistance. It can be molded into molded parts, films, sheets, fibers, etc. by injection molding and extrusion molding, so it is widely used in fields requiring heat resistance and chemical resistance, such as electrical / electronic parts, mechanical parts, and automotive parts. Yes. Among them, PAS used for extrusion molding of fibers and films is required to have a low crystallization temperature in order to suppress yarn breakage during melt spinning and film breakage / cracking during melt film formation (patent) Reference 1).

  Currently, the industrial production method of PAS, which has become the mainstream, comprises alkali metal sulfide such as sodium sulfide and polyhaloaromatic compound such as p-dichlorobenzene in an organic amide solvent such as N-methyl-2-pyrrolidone. It is a reaction. PAS produced by this method has a large dispersion index expressed by the ratio of the weight average molecular weight to the number average molecular weight, and contains many low molecular weight components. Therefore, the amount of volatile components generated during heating, that is, gas generation during heating. There is a problem that the amount is large. Since the generation of volatile components causes mold / die contamination during melt molding, reduction of the volatile components is desired from the viewpoint of improving quality and productivity. As a method for producing PAS with reduced generation of volatile components during heating, a method for producing PAS in which cyclic polyarylene sulfide is heated in the absence of a solvent has been proposed (Patent Document 2).

  As a known technique related to the above technique, as a method for producing a PAS containing a reactive functional group, when a cyclic polyarylene sulfide is heated, a sulfide compound having a functional group represented by an amino group is allowed to coexist. In addition to the proposed method (Patent Document 3), as a method for improving the polymerization rate in producing PAS, a method in which an ionic compound typified by a sodium salt of thiophenol and a Lewis acid coexist (Patent Document 4). ), A method of coexisting a metal carboxylate (Patent Document 5) has been proposed.

Japanese Patent Laying-Open No. 2005-225931 International Publication No. 2007/034800 International Publication No. 2012/057319 Japanese Patent Laid-Open No. 5-301962 JP 2011-173953 A

  In the method described in Patent Document 2, since a solvent is not used when PAS is produced, the obtained PAS is highly pure, and the content of low molecular weight components is low, the weight during heating is reduced. It is believed that a PAS with reduced reduction is obtained. However, this method has a problem that it is difficult to obtain a PAS having a low crystallization temperature suitable for melt spinning and film formation.

  Among known techniques, PAS obtained by the methods described in Patent Documents 3 and 4 reduces the crystallization temperature, although the amount of gas generated during heating is small, similar to PAS obtained by the method described in Patent Document 2. No effect has been found, and PAS obtained by the method described in Patent Document 5 has a problem that the amount of gas generated during heating increases.

  It is an object of the present invention to provide a polyarylene sulfide that has been difficult to achieve in the prior art and has a reduced crystallization temperature and a solidification temperature, and generates a small amount of gas during heating.

That is, the present invention is as follows.
1. The cyclic polyarylene sulfide (a) is 0.1 mol% to 10 mol% of the sulfide compound (b) represented by the following formula (B1) or (B2) with respect to the sulfur atom in the cyclic polyarylene sulfide. A process for producing polyarylene sulfide (c), which is heated in the presence;

S is a sulfur atom, X and Y are, -O -, - S -, - CO 2 -, - SO 3 - either, M is an alkaline earth metal, Z is located at the carboxyl group having 1 to 3 carbon atoms , L and m each represents an integer of 0 or 1.
2. 2. The cyclic polyarylene sulfide (a) comprises at least 50% by weight or more of the cyclic compound represented by the following formula (A), and the repeating number n in the formula is 4 to 50 Production method of polyarylene sulfide (c);

Ar represents an arylene group.
3. The method for producing polyarylene sulfide (c) according to 1 or 2 above, wherein the heating is performed in the absence of a solvent,
4). The weight average molecular weight of the resulting polyarylene sulfide (c) is 10,000 or more, and the polydispersity index represented by the weight average molecular weight / number average molecular weight is 2.5 or less. A process for producing the polyarylene sulfide (c) according to any one of the above,
5. The method for producing a polyarylene sulfide (c) according to any one of claims 1 to 4, wherein the weight loss when the resulting polyarylene sulfide (c) is heated satisfies the following formula:
ΔWr = (W ₁₀₀ −W ₃₃₀ ) / W ₁₀₀ × 100 ≦ 0.18 (%)
ΔWr is a weight loss rate, and when thermogravimetric analysis was performed at a temperature rising rate of 20 ° C./min from 50 ° C. to an arbitrary temperature of 330 ° C. or higher in a non-oxidizing atmosphere at normal pressure, when the temperature reached 100 ° C. This is a value obtained from the sample weight (W ₁₀₀ ) and the sample weight (W ₃₃₀ ) when reaching 330 ° C.
6). 6. The poly according to any one of 1 to 5 above, wherein X and Y contained in the sulfide compound (b) represented by the formula (B1) or (B2) are either —O— or —CO ₂ —. Production method of arylene sulfide (c),
7). The method for producing polyarylene sulfide (c) according to any one of 1 to 6 above, wherein the alkaline earth metal contained in the sulfide compound (b) represented by the formula (B1) or (B2) is calcium. is there.

  According to the present invention, in the production of polyarylene sulfides for heating cyclic polyarylene sulfides, the production of polyarylene sulfides having a reduced crystallization temperature and solidification temperature while maintaining the feature of low gas generation during heating. Is possible. That is, it is possible to provide a polyarylene sulfide having a low crystallization temperature and a solidification temperature and a small amount of gas generation during heating.

  Hereinafter, the present invention will be described in detail. The method for producing a polyarylene sulfide of the present invention is characterized in that the cyclic polyarylene sulfide (a) is converted to the polyarylene sulfide (c) by heating in the presence of the sulfide compound (b).

(1) Cyclic polyarylene sulfide (a)
The cyclic polyarylene sulfide in the method for producing polyarylene sulfide of the present invention is the following general formula (A)

It is a composition containing the cyclic compound represented by these. The cyclic polyarylene sulfide preferably contains at least 50 wt% or more of a cyclic compound containing 80 mol% or more of a repeating unit of — (Ar—S) — in the structural unit, preferably 70 wt% or more. More preferably, it contains 80% by weight or more, more preferably 90% by weight or more.

  Ar includes units selected from the following formulas (C) to (M), among which the unit represented by formula (C) is particularly preferable.

R1 and R2 are substituents selected from hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an arylene group having 6 to 24 carbon atoms, and a halogen group, and R1 and R2 may be the same May be different.

  The cyclic compound of the formula (A) may be a random copolymer containing a plurality of repeating units selected from the formula (C) to the formula (M), or may be a block copolymer. Or a mixture thereof. Typical examples of these include cyclic polyphenylene sulfide, cyclic polyphenylene sulfide sulfone, cyclic polyphenylene sulfide ketone, cyclic random copolymers thereof, cyclic block copolymers, and mixtures thereof. Particularly preferred cyclic compounds of the formula (A) include p-phenylene sulfide units as the main structural unit.

Is a cyclic polyphenylene sulfide containing 80 mol% or more, particularly 90 mol% or more.

  Although there is no restriction | limiting in particular in the repeating number n of the cyclic compound of the said formula (A) contained in cyclic polyarylene sulfide, 4-50 are preferable. The upper limit of the repeating number n is more preferably 25 or less, and further preferably 15 or less. As described later, the conversion of the cyclic polyarylene sulfide to the polyarylene sulfide by heating is preferably performed at a temperature equal to or higher than the temperature at which the reaction mixture containing the cyclic polyarylene sulfide is melted. Since the melting temperature of the cyclic polyarylene sulfide tends to increase as the number of repetitions n increases, the conversion of the cyclic polyarylene sulfide to the polyarylene sulfide can be performed at a lower temperature. It is advantageous to set the number of repetitions n within the above range.

  The cyclic compound of the formula (A) contained in the cyclic polyarylene sulfide may be either a single compound having a single repeating number or a mixture of cyclic compounds having different repeating numbers. Since a mixture of cyclic compounds having different numbers of repetitions tends to have a lower melting temperature than a single compound having a single number of repetitions, the temperature during the conversion to polyarylene sulfide can be lowered. preferable.

  The cyclic polyarylene sulfide may be a mixture containing components other than the cyclic compound of the formula (A). The cyclic compound of the formula (A) is preferably contained at least 50% by weight, more preferably 70% by weight or more, further preferably 80% by weight or more, and further preferably 90% by weight or more. The upper limit of the amount of the cyclic compound of the formula (A) contained in the cyclic polyarylene sulfide is not particularly limited, but 98% by weight or less, preferably 95% by weight or less can be exemplified as a preferable range. Usually, the higher the weight ratio of the cyclic compound in the cyclic polyarylene sulfide, the higher the molecular weight of the polyarylene sulfide obtained after heating. That is, it is possible to easily adjust the molecular weight of the polyarylene sulfide obtained by adjusting the weight ratio of the cyclic compound in the cyclic polyarylene sulfide. In addition, when the weight ratio of the cyclic compound in the cyclic polyarylene sulfide exceeds the upper limit described above, the melting temperature of the reaction mixture tends to increase, so that the weight ratio of the cyclic compound is in the above range, This is preferable because the temperature during the conversion of the cyclic polyarylene sulfide to the polyarylene sulfide can be further lowered.

  The component other than the cyclic compound of the formula (A) in the cyclic polyarylene sulfide is particularly preferably a linear polyarylene sulfide oligomer. Here, the linear polyarylene sulfide oligomer is a linear homo-oligomer or co-oligomer having a repeating unit of-(Ar-S)-as a main constituent unit, preferably containing 80 mol% or more of the repeating unit. . Ar includes units represented by the formulas (C) to (M) and the like, and among them, a unit represented by the formula (C) is particularly preferable.

  Typical examples of these include polyphenylene sulfide oligomers, polyphenylene sulfide sulfone oligomers, polyphenylene sulfide ketone oligomers, random copolymers, block copolymers, and mixtures thereof. Particularly preferred polyarylene sulfide oligomers include p-phenylene sulfide units as the main structural unit of the polymer.

Is a polyphenylene sulfide oligomer containing 80 mol% or more, particularly 90 mol% or more.

  Examples of the molecular weight of the linear polyarylene sulfide oligomer include those having a molecular weight lower than that of the polyarylene sulfide, and specifically, the molecular weight is preferably less than 10,000.

  The upper limit of the molecular weight of the cyclic polyarylene sulfide used for the production of the polyarylene sulfide of the present invention is preferably 10,000 or less, more preferably 5,000 or less, and further preferably 3,000 or less in terms of weight average molecular weight. On the other hand, the lower limit of the molecular weight is preferably 300 or more, preferably 400 or more, and more preferably 500 or more in terms of weight average molecular weight.

(2) Sulfide compound (b)
The sulfide compound in the method for producing polyarylene sulfide of the present invention is a compound represented by the formula (B1) or (B2).

In the sulfide compound represented by the formula (B1) or (B2), X and Y represent any of —O—, —S—, —CO ₂ —, and —SO ₃ —. X and Y are preferably any of —O—, —CO ₂ —, and —SO ₃ — from the viewpoint of the stability of the sulfide compound. X and Y are preferably any of —O—, —S—, and —CO ₂ — from the viewpoint of availability. X and Y may be the same or different.

In the sulfide compound represented by the formula (B1) or (B2), the position where X and Y are bonded is any of the ortho, meta, and para positions of the sulfide bond in the formulas (B1) and (B2). The position can be taken. Among these, when synthesizing a sulfide compound, from the viewpoints of less steric hindrance and improved yield, the meta and para positions are more preferable, and the para position is more preferable. On the other hand, when X and Y are —CO ₂ — or —SO ₃ —, these substituents exhibit electron-withdrawing properties, so that bonding to the ortho-position and para-position synthesizes a sulfide compound. This is preferable from the viewpoint of improving the yield.

  M represents an alkaline earth metal and is any one of calcium, strontium, and barium. Among these, calcium is preferable from the viewpoint of availability.

Z represents a carboxyl group having 1 to 3 carbon atoms, and is any one of a formic acid residue, an acetic acid residue, and a propionic acid residue. If the formula is used, it can be expressed as RCOO-, where R is any one of hydrogen, a methyl group, and an ethyl group.
l and m are integers representing 0 or 1;

  When the structure of the sulfide compound having an alkaline earth metal salt structure is symmetric, it is particularly preferable from the viewpoint of easy preparation.

  The lower limit of the amount of sulfide compound added in the method for producing polyarylene sulfide of the present invention is preferably 0.1 mol% or more, more preferably 1 mol% or more, based on the sulfur atom in the cyclic polyarylene sulfide. On the other hand, the upper limit of the addition amount is preferably 10 mol% or less, more preferably 5 mol% or less, and even more preferably 3 mol% or less with respect to the sulfur atom in the cyclic polyarylene sulfide (a). If the addition amount of the sulfide compound is less than the above range, it is difficult to obtain the effect of lowering the crystallization temperature and the solidification temperature of the polyarylene sulfide, which is the effect of the present invention. Conversely, if the addition amount exceeds the above range, the polyarylene sulfide This is not preferable because it causes an increase in the amount of gas generated during heating and a decrease in the mechanical strength of the molded product.

  Specific examples of the sulfide compound include those shown in Formula (B1a) to Formula (B1n) and Formula (B2a) to Formula (B2i).

  M is any one of calcium, strontium, and barium, and R3 is any one of hydrogen, a methyl group, and an ethyl group.

  The sulfide compound can be prepared from the corresponding sulfide compound. The preparation method is not limited. For example, in the case of a compound represented by the formula (B2f), 4 mol of sodium hydroxide is added to 1 mol of 5,5′-thiodisalicylic acid in ion-exchanged water. By making it act, it is set as the aqueous solution of the sodium salt of 5, 5'- thiodisalicylic acid. The target compound is produced and precipitated by adding an aqueous solution containing 4 mol or more of alkaline earth metal acetate. The precipitate can be filtered and washed with ion-exchanged water to remove the water-soluble metal salt for purification.

(3) Polyarylene sulfide The polyarylene sulfide in the present invention is a homopolymer or copolymer having a repeating unit of the formula:-(Ar-S)-as a main structural unit. Here, a main structural unit means that the said structural unit contains 80 mol% or more in all the structural units contained in a polymer. Ar includes a unit represented by a structural formula selected from the above formulas (C) to (M), among which the unit represented by the formula (C) is particularly preferable.

  As long as the repeating unit of the formula (C) to the formula (M) is a main constituent unit, it can contain a small amount of branching units or crosslinking units represented by the following formulas (N) to (P). The copolymerization amount of these branch units or cross-linking units is preferably in the range of 0 mol% to 1 mol% with respect to the arylene sulfide unit represented by-(Ar-S)-.

  The polyarylene sulfide may be any of a random copolymer, a block copolymer, and a mixture thereof.

  Typical examples of the polyarylene sulfide include polyphenylene sulfide, polyphenylene sulfide sulfone, polyphenylene sulfide ketone, random copolymers thereof, block copolymers, and mixtures thereof. Particularly preferred polyarylene sulfides include p-phenylene sulfide units as the main structural unit of the polymer.

Is polyphenylene sulfide containing 80 mol% or more, preferably 90 mol% or more.

(4) Production method of polyarylene sulfide (c) In the present invention, the polyarylene sulfide (c) is obtained by heating the cyclic polyarylene sulfide (a) in the presence of the sulfide compound (b).

  The heating temperature is preferably a temperature at which the cyclic polyarylene sulfide (a) melts. When the heating temperature is lower than the melting temperature of the reaction mixture, the heating time required to obtain polyarylene sulfide tends to be long.

  The temperature at which the cyclic polyarylene sulfide (a) melts varies depending on the composition and molecular weight of the cyclic polyarylene sulfide (a) and the environment during heating. For example, the reaction mixture is analyzed with a differential scanning calorimeter. By doing so, it is possible to grasp the melting temperature. As a minimum of heating temperature, 180 ° C or more can be illustrated, preferably 200 ° C or more, more preferably 220 ° C or more, still more preferably 240 ° C or more. In this temperature range, the cyclic polyarylene sulfide (a) melts and the polyarylene sulfide (c) can be obtained in a short time. On the other hand, if the temperature is too high, an undesirable side reaction represented by a crosslinking reaction or a decomposition reaction tends to occur, and the characteristics of the resulting polyarylene sulfide may be deteriorated. It is desirable to avoid temperatures where the reaction occurs significantly. As an upper limit of heating temperature, 400 degrees C or less can be illustrated, Preferably it is 360 degrees C or less, More preferably, it is 340 degrees C or less. Below this temperature, the adverse effects on the properties of the resulting polyarylene sulfide due to undesirable side reactions tend to be suppressed, and polyarylene sulfide (c) having excellent properties can be obtained.

  The heating time is uniform because it varies depending on the content of the cyclic compound of the formula (A) in the cyclic polyarylene sulfide (a), the number n of repetitions, the molecular weight and other conditions, and the conditions such as the heating temperature. However, it is preferable to set so that the above-mentioned undesirable side reaction does not occur as much as possible. Examples of the heating time include 0.05 hours to 100 hours, preferably 0.1 hours to 20 hours, and more preferably 0.1 hours to 10 hours.

  It is preferable to heat the reaction mixture composed of the cyclic polyarylene sulfide (a) and the sulfide compound (b) under conditions that do not substantially contain a solvent. In the case of carrying out under such conditions, in addition to being able to reduce the gas component derived from the solvent, it is possible to raise the temperature in a short time, so that polyarylene sulfide (c) tends to be obtained in a short time. Here, the condition containing substantially no solvent means that the solvent in the reaction mixture is 10% by weight or less, more preferably 3% by weight or less, and still more preferably no solvent at all.

  The heating may be performed by a method using a normal polymerization reaction apparatus, or may be performed in a mold for producing a molded product, or may be performed by using an extruder or a melt kneader. If it is an apparatus, it can carry out without a restriction | limiting especially, and well-known methods, such as a batch system and a continuous system, are employable.

  The atmosphere for heating the reaction mixture composed of the cyclic polyarylene sulfide (a) and the sulfide compound (b) is preferably a non-oxidizing atmosphere, and it is also preferably performed under reduced pressure. Moreover, when it carries out under pressure reduction conditions, it is preferable to make it the pressure reduction conditions after making the atmosphere in a reaction system once non-oxidizing atmosphere. This tends to suppress the occurrence of undesirable side reactions such as cross-linking reactions and decomposition reactions between cyclic polyarylene sulfides and polyarylene sulfides produced by heating, and between polyarylene sulfides and cyclic polyarylene sulfides. is there. Note that the non-oxidizing atmosphere is an atmosphere in which the oxygen concentration in the gas phase in contact with the reaction mixture is 5% by volume or less, preferably 2% by volume or less, more preferably an oxygen-free atmosphere, that is, nitrogen, helium, argon or the like. It indicates an inert gas atmosphere, and among these, a nitrogen atmosphere is particularly preferable from the viewpoints of economy and ease of handling. The reduced pressure condition means that the reaction system is lower than atmospheric pressure, and the upper limit is preferably 50 kPa or less, more preferably 20 kPa or less, and even more preferably 10 kPa or less. An example of the lower limit is 0.1 kPa or more. Below the preferred lower limit, depending on the reaction temperature, the cyclic compound having a low molecular weight contained in the cyclic polyarylene sulfide (a) tends to be volatilized.

  Further, the reaction mixture composed of the cyclic polyarylene sulfide (a) and the sulfide compound (b) can be heated in the presence of a filler. Examples of the filler include non-fibrous glass, non-fibrous carbon, and inorganic fillers such as calcium carbonate, titanium oxide, and alumina.

  It is also possible to use various catalyst components that promote conversion during heating of the reaction mixture comprising the cyclic polyarylene sulfide (a) and the sulfide compound (b). As such a catalyst component, for example, various zero-valent transition metal compounds disclosed in JP 2012-176607 A are used. As the zero-valent transition metal, groups 8 to 11 of the periodic table and the fourth period are used. To 6th period metals are preferably used. For example, nickel, palladium, platinum, iron, ruthenium, rhodium, copper, silver, and gold can be exemplified as the metal species. Various complexes are suitable as the zero-valent transition metal compound. For example, triphenylphosphine, tri-t-butylphosphine, tricyclohexylphosphine, 1,2-bis (diphenylphosphino) ethane, 1 , 1'-bis (diphenylphosphino) ferrocene, dibenzylideneacetone, dimethoxydibenzylideneacetone, cyclooctadiene, and carbonyl complexes. Specifically, bis (dibenzylideneacetone) palladium, tris (dibenzylideneacetone) dipalladium, tetrakis (triphenylphosphine) palladium, bis (tri-t-butylphosphine) palladium, bis [1,2-bis (diphenylphosphine) Fino) ethane] palladium, bis (tricyclohexylphosphine) palladium, [P, P′-1,3-bis (di-i-propylphosphino) propane] [P-1,3-bis (di-i-propyl) Phosphino) propane] palladium, 1,3-bis (2,6-di-i-propylphenyl) imidazol-2-ylidene (1,4-naphthoquinone) palladium dimer, 1,3-bis (2,4 , 6-Trimethylphenyl) imidazol-2-ylidene (1,4-naphthoquinone) palladium dimer, bi (3,5,3 ′, 5′-dimethoxydibenzylideneacetone) palladium, bis (tri-t-butylphosphine) platinum, tetrakis (triphenylphosphine) platinum, tetrakis (trifluorophosphine) platinum, ethylenebis (tri Phenylphosphine) platinum, platinum-2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane complex, tetrakis (triphenylphosphine) nickel, tetrakis (triphenylphosphite) nickel, Examples thereof include bis (1,5-cyclooctadiene) nickel, dodecacarbonyltriiron, pentacarbonyliron, dodecacarbonyltetrarhodium, hexadecacarbonyl6rhodium, dodecacarbonyltriruthenium, and the like. These polymerization catalysts may be used alone or in combination of two or more. When such a zero-valent transition metal compound is used as a catalyst component, cyclic polyarylene sulfide can be highly polymerized in a short time, and generation of volatile components due to undesirable side reactions can be suppressed. preferable.

(5) Polyarylene sulfide obtained by the present invention The polyarylene sulfide obtained by the production method of the present invention has a temperature drop crystallization temperature in the range of 140 ° C to 220 ° C in a preferred embodiment, and a temperature drop crystallization in a more preferred embodiment. The temperature satisfies the range of 140 ° C to 200 ° C. The temperature-falling crystallization temperature in the present invention represents the peak top temperature of an exothermic peak observed when the molten polyarylene sulfide is cooled at 40 ° C./min and crystallized in differential scanning calorimetry.

  The temperature-falling crystallization temperature can be measured by general differential scanning calorimetry. In measuring the temperature-falling crystallization temperature, it is important to perform the measurement from a state where the entire sample is melted. When the total amount of the sample is not melted, the influence on the crystallization by the infusible resin cannot be ignored, and it is difficult to accurately compare the crystallization characteristics of the samples. The heating conditions under which the total amount of the sample in the measurement of the temperature-falling crystallization temperature is in a molten state differ depending on the structural unit and molecular weight of the polyarylene sulfide, the heating rate during heating, etc. Can be exemplified by 240 ° C. to 340 ° C., and the holding time at the melting temperature can be exemplified by 1 minute to 5 minutes. Among them, it is preferable to maintain the melting condition at 340 ° C. for 1 minute when measuring the temperature-falling crystallization temperature of polyphenylene sulfide as the main structural unit of p-phenylene sulfide.

  In addition, the cooling condition in the measurement of the temperature-falling crystallization temperature is not particularly limited as long as it can be set by a general differential scanning calorimeter, but the cooling rate can be 10 ° C / min to 100 ° C / min. An example of the ultimate temperature after cooling is 100 ° C. or lower. Among them, the cooling rate is preferably 10 ° C./min to 50 ° C./min for the purpose of comparing the crystallization characteristics at the time of extrusion molding.

  The temperature-falling crystallization temperature is desirably measured with a sample amount of about 10 mg, and the shape of the sample is desirably a fine particle of about 2 mm or less.

  Further, the polyarylene sulfide obtained by the production method of the present invention satisfies a solidification temperature range of 170 ° C. to 240 ° C. in a preferred embodiment, and a solidification temperature range of 170 ° C. to 230 ° C. in a more preferred embodiment. What is the solidification temperature in the present invention? In the measurement of viscoelasticity, the polyarylene sulfide in a molten state is cooled at 10 ° C / min, and the temperature at which the viscosity rises with the solidification of the polyarylene sulfide (solidification start temperature) and solidification is completed. The intermediate temperature of the temperature at which the viscosity increase ends (solidification end temperature) is expressed.

  The solidification temperature can be measured by general viscoelasticity measurement. In measuring the solidification temperature, it is important to perform the measurement from a state where the entire sample is melted. When the total amount of the sample is not melted, the influence on the solidification by the infusible resin cannot be ignored, and it is difficult to accurately compare the solidification characteristics of the samples. Although the heating conditions under which the total amount of the sample in the measurement of the solidification temperature is in a molten state differ depending on the structural unit and molecular weight of polyarylene sulfide, the heating rate during heating, etc., it cannot be defined uniformly, but the melting temperature is 240. C. to 340.degree. C. can be exemplified, and the holding time at the melting temperature can be exemplified by 1 to 5 minutes. Among these, it is preferable to maintain the melting condition at 320 ° C. for 1 minute when measuring the solidification temperature of polyphenylene sulfide having p-phenylene sulfide as a main structural unit.

  In addition, the cooling condition in the measurement of the solidification temperature is not particularly limited as long as it can be set by a general viscoelasticity measuring apparatus, but the cooling rate can be exemplified as 5 ° C./min to 20 ° C./min. Examples of the ultimate temperature include 120 ° C. or lower. Among them, the cooling rate is preferably 10 ° C./min to 20 ° C./min for the purpose of comparing solidification characteristics during extrusion molding.

  The measurement of the solidification temperature is desirably performed with a sample amount of about 0.7 g, and the shape of the sample is desirably a pellet or fine particle of about 3 mm or less.

  The measurement conditions of the temperature-falling crystallization temperature and the solidification temperature described above are based on the temperature change when melt-molding polyarylene sulfide represented by polyphenylene sulfide. Therefore, the temperature-falling crystallization temperature and the solidification temperature under the preferred measurement conditions are low. It can be said that polyarylene sulfide has a low cooling crystallization / solidification rate during melt molding. Such polyarylene sulfides with a low temperature crystallization / solidification rate are less susceptible to yarn breakage during melt spinning and film tearing / cracking during melt casting in extrusion applications such as fibers and films. It can be said that it is a high and excellent polyarylene sulfide.

  Further, the polydispersity index represented by the spread of the molecular weight distribution of the polyarylene sulfide obtained by the production method of the present invention, that is, the ratio between the weight average molecular weight and the number average molecular weight (weight average molecular weight / number average molecular weight) is a preferred embodiment. And 2.5 or less in a more preferred embodiment. The weight average molecular weight and the number average molecular weight are molecular weights obtained by measuring standard substances having known absolute molecular weights such as polystyrene and polymethyl methacrylate using size exclusion chromatography equipped with a differential refractive index detector. It is possible to create a calibration curve from the relationship between the retention time and the retention time. As the measurement conditions for size exclusion chromatography, a combination of a solvent and a temperature capable of dissolving polyarylene sulfide at a concentration of 0.1% by weight can be used. Examples of the solvent (eluent) include 1-chloronaphthalene or N-methyl-ε-caprolactam. The measurement temperature can be exemplified by a range of 50 ° C. to 250 ° C., but may be different for each process constituting the apparatus such as a column and a detector.

  The polyarylene sulfide having a small polydispersity index represented by the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) obtained by the above measurement tends to have a low content of low molecular components. It can be said that this is an excellent polyarylene sulfide having a high quality since it generates a small amount of gas when melt-molding and a small amount of eluted components when it comes into contact with a solvent.

In addition, the polyarylene sulfide obtained by the production method of the present invention is different from the one obtained by a general synthesis method, and has a feature that the amount of gas generated during heating is small. Equation (1) is satisfied.
ΔWr = (W ₃₃₀ −W ₁₀₀ ) / W ₁₀₀ × 100 ≦ 0.18 (%) (1)
ΔWr is the weight loss rate, and when it reaches 100 ° C. when thermogravimetric analysis is performed at a rate of temperature increase of 20 ° C./min from 50 ° C. to an arbitrary temperature of 330 ° C. or higher in a non-oxidizing atmosphere at normal pressure This is a value obtained from the sample weight (W ₁₀₀ ) and the sample weight (W ₃₃₀ ) when reaching 330 ° C.

  The ΔWr satisfies 0.18% or less in a preferred embodiment, 0.12% or less in a more preferred embodiment, 0.10% or less in a further preferred embodiment, and 0.085% or less in a still more preferred embodiment.

  The weight reduction rate ΔWr can be obtained by a general thermogravimetric analysis. As the atmosphere in this analysis, a normal pressure non-oxidizing atmosphere is used. The non-oxidizing atmosphere is an atmosphere in which the oxygen concentration in the gas phase in contact with the sample is 5% by volume or less, preferably 2% by volume or less, and more preferably substantially free of oxygen. The atmosphere containing substantially no oxygen means an atmosphere of an inert gas such as nitrogen, helium, or argon. Among these, a nitrogen atmosphere is particularly preferable from the viewpoints of economy and ease of handling. The normal pressure is atmospheric pressure, that is, a pressure in the vicinity of the standard state of the atmosphere, and is a pressure condition in the vicinity of 101.3 kPa as an absolute pressure. For measurements other than the above, such as when polyarylene sulfide is oxidized during measurement, or when it is very different from the atmosphere actually used for molding polyarylene sulfide It may not be possible.

  In the measurement of the weight reduction rate ΔWr, the thermogravimetric analysis is performed by increasing the temperature from 50 ° C. to an arbitrary temperature of 330 ° C. or more at a temperature increase rate of 20 ° C./min. Preferably, after holding at 50 ° C. for 1 minute, the temperature is increased at a rate of temperature increase of 20 ° C./min to perform thermogravimetric analysis. This temperature range is a temperature range frequently used when polyarylene sulfide typified by polyphenylene sulfide is actually used. Also, it is frequently used when a solid polyarylene sulfide is melted and then molded into an arbitrary shape. It is also a temperature range. The weight reduction rate in the actual use temperature region is related to the amount of gas generated from the polyarylene sulfide during actual use, the amount of components adhering to the die or mold during molding, and the like. Therefore, a polyarylene sulfide having a small ΔWr can be said to be an excellent polyarylene sulfide having a high quality. The weight reduction rate is desirably measured with a sample amount of about 10 mg, and the shape of the sample is desirably a fine particle of about 2 mm or less.

  Further, the polyarylene sulfide obtained by the production method of the present invention has a feature that the amount of lactone type compound and / or aniline type compound generated when heated is remarkably small. Examples of the lactone type compound include β-propiolactone, β-butyrolactone, β-pentanolactone, β-hexanolactone, β-heptanolactone, β-octanolactone, β-nonalactone, and β-decalactone. , Γ-butyrolactone, γ-valerolactone, γ-pentanolactone, γ-hexanolactone, γ-heptanolactone, γ-octalactone, γ-nonalactone, γ-decalactone, δ-pentanolactone, δ-hexa Nolactone, δ-heptanolactone, δ-octanolactone, δ-nonalactone, δ-decalactone, etc. can be exemplified, and aniline type compounds include aniline, N-methylaniline, N, N-dimethylaniline, N -Ethylaniline, N-methyl-N-ethylaniline, 4-chloro-aniline, 4-chloro-N-methyl Niline, 4-chloro-N, N-dimethylaniline, 4-chloro-N-ethylaniline, 4-chloro-N-methyl-N-ethylaniline, 3-chloro-aniline, 3-chloro-N-methylaniline, Examples include 3-chloro-N, N-dimethylaniline, 3-chloro-N-ethylaniline, 3-chloro-N-methyl-N-ethylaniline and the like.

  Generation of lactone-type compounds and / or aniline-type compounds when polyarylene sulfide is heated causes factors such as resin foaming during molding and mold contamination, as well as deterioration of molding processability, as well as contamination of the surrounding environment. Therefore, it is desired to reduce the generation amount as much as possible, and the generation amount of the lactone type compound is preferably 500 ppm or less, more preferably 300 ppm, based on the weight of the polyarylene sulfide before heating. More preferably, it is 100 ppm or less, and still more preferably 50 ppm or less. Similarly, the amount of aniline type compound generated is preferably 300 ppm or less, more preferably 100 ppm, still more preferably 50 ppm or less, and even more preferably 30 ppm or less. As a method for evaluating the amount of lactone-type compound and / or aniline-type compound generated when polyarylene sulfide is heated, the gas generated when treated at 320 ° C. for 60 minutes in a non-oxidizing atmosphere is gas chromatographed. An example is a method of dividing and quantifying.

  In the production method of the present invention, the conversion rate of cyclic polyarylene sulfide to polyarylene sulfide is preferably 70% or more, more preferably 80% or more, from the viewpoint of obtaining a polyarylene sulfide having the above-mentioned characteristics. 90% or more is more preferable.

  The polyarylene sulfide obtained by the present invention exhibits excellent low gas properties, low crystallization / solidification temperature, excellent heat resistance, chemical resistance, mechanical properties, injection molding, injection compression molding, blow molding In addition, it has characteristics suitable for extrusion molding applications such as sheets, films, fibers and pipes.

  Hereinafter, the method of the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In addition, the measuring method of a physical property is as follows.

<Molecular weight measurement>
The molecular weights of polyarylene sulfide sulfide and cyclic polyarylene sulfide were measured by gel permeation chromatography (GPC), which is a type of size exclusion chromatography (SEC), under the following conditions, and the molecular weight was calculated in terms of polystyrene.
Apparatus: SSC-7110 manufactured by Senshu Scientific
Column name: Showex Denko Shodex UT-806M × 2
Detector: Differential refractive index detector Column temperature: 210 ° C
Pre-constant temperature: 250 ° C
Pump bath temperature: 50 ° C
Detector temperature: 210 ° C
Eluent: 1-chloronaphthalene flow rate: 1.0 mL / min
Sample concentration: 0.1% by weight
Sample injection volume: 300 μL.

<Measurement of weight loss during heating>
The weight change rate during heating of the polyarylene sulfide was measured under the following conditions using a thermogravimetric analyzer. The weight reduction rate ΔWr is calculated using the above equation (1) from the sample weight (W ₁₀₀ ) when reaching 100 ° C. and the sample weight (W ₃₃₀ ) when reaching 330 ° C. when the temperature is raised from 50 ° C. to 350 ° C. did. In addition, the sample used the fine granule of 2 mm or less.
Equipment: TGA7 manufactured by PerkinElmer
Measurement atmosphere: Sample preparation weight under nitrogen stream: 10 mg
Measurement condition:
・ Hold at 50 ° C. for 1 minute.

<Analysis of gas components generated during heating>
The gas component generated when polyarylene sulfide was heated was quantified by the following method. In addition, the sample used the fine granule of 2 mm or less.

Collection of gas generated during heating:
About 10 mg of polyarylene sulfide was heated at 320 ° C. under a nitrogen stream (50 ml / min) for 60 minutes, and the generated gas component was collected in a thermal trap tube carbotrap 400 for collecting air.

Analysis of gas components:
The gas component collected in the tube was thermally desorbed by raising the temperature from room temperature to 280 ° C. over 5 minutes using a thermal desorption apparatus TDU (manufactured by Supelco). The thermally desorbed component was divided into components by gas chromatography, and γ-butyrolactone and 4-chloro-N-methylaniline in the gas were quantified.

<Measurement of falling crystallization temperature>
The thermal characteristics of polyarylene sulfide were measured under the following conditions using a differential scanning calorimeter. The value of the peak top temperature of the second run endothermic peak was used as the melting point, and the value of the peak top temperature of the first run exothermic peak was used as the cooling crystallization temperature. In addition, the sample used the fine granule of 2 mm or less.
Apparatus: Q20 manufactured by TA Instruments
Measurement atmosphere: Sample preparation weight under nitrogen stream: 10 mg
Measurement condition:
(First Run)
-Hold at 50 ° C for 1 minute-Increase the temperature from 50 ° C to 340 ° C at a heating rate of 40 ° C / minute-Hold at 340 ° C for 1 minute-Cool from 340 ° C to 100 ° C at a cooling rate of 40 ° C / minute (Second Run)
• Hold at 100 ° C. for 1 minute • Increase the temperature from 100 ° C. to 340 ° C. at a temperature increase rate of 40 ° C./min. • Hold at 340 ° C. for 1 minute.

<Measurement of solidification temperature>
The solidification temperature of the polyarylene sulfide is measured under the following conditions using a viscoelasticity measuring device. The solidification temperature is a temperature at which the viscosity increase starts with the solidification of the polyarylene sulfide (solidification start temperature), and the viscosity increases when the solidification is completed. Was determined as an intermediate temperature between the temperatures at which the saturation ends (solidification completion temperature).
Apparatus: Physica MCR501 manufactured by Anton Paar
Plate: 25 mmφ parallel plate Measurement mode: Vibration shear stress: 1000 Pa
Frequency: 1Hz
Measurement conditions: Cooling from 320 ° C. to 120 ° C. at a cooling rate of 10 ° C./min.

[Reference Example 1]
<Preparation of slurry containing polyphenylene sulfide mixture>
A stainless steel reactor 1 equipped with a stirrer was charged with 1169 kg (10.0 kgmol) of 48% aqueous sodium hydrosulfide, 841 kg (10.1 kgol) of 48% aqueous sodium hydroxide, 1983 kg, 50% sodium acetate aqueous solution 322 kg, and gradually heated to about 240 ° C. over about 3 hours while passing nitrogen at normal pressure, and distilled water 1200 kg and NMP 26 kg through the rectification tower. did. In addition, 0.02 mol% hydrogen sulfide of the sulfur atoms charged during this liquid removal operation scattered out of the system.

  Subsequently, after cooling to about 200 degreeC, the content was transferred to the stainless steel reactor 2 with another stirrer. The reactor 1 was charged with 932 kg of NMP, the inside was washed, and the washing liquid was transferred to the reactor 2. Next, 1477 kg (10.0 kgol) of p-dichlorobenzene was added to the reactor 2, sealed under nitrogen gas, and heated to 200 ° C. with stirring. Next, the temperature was raised from 200 ° C. to 270 ° C. at a rate of 0.6 ° C./min, and held at this temperature for 140 minutes. While 353 kg of water was injected over 15 minutes, it was cooled to 250 ° C. at a rate of 1.3 ° C./min. Thereafter, it was cooled to 220 ° C. at a rate of 0.4 ° C./min, and then rapidly cooled to about 80 ° C. to obtain a slurry (A).

  This slurry (A) was diluted with 2623 kg of NMP to obtain a slurry (B). The slurry (B) heated to 80 ° C. was filtered through a sieve (80 mesh, opening 0.175 mm) to obtain a granular PPS resin containing the slurry as a mesh-on component and a slurry (C) as a filtrate component. .

[Reference Example 2]
<Preparation of polyphenylene sulfide mixture>
1000 kg of the slurry (C) obtained in Reference Example 1 was charged into a stainless steel reactor, the inside of the reactor was replaced with nitrogen, and then treated at 100 ° C. to 150 ° C. under reduced pressure for about 1.5 hours with stirring. Most of the solvent was removed.

  Next, 1200 kg of ion-exchanged water was added, and the mixture was stirred at about 70 ° C. for 30 minutes to form a slurry. The slurry was filtered to obtain a white solid. Add 1200 kg of ion-exchanged water to the obtained solid, stir again at 70 ° C. for 30 minutes, re-slurry in the same way, and after filtration, dry at 120 ° C. in a nitrogen atmosphere, and then dry under reduced pressure at 80 ° C. 11.6 kg of product was obtained.

  From the absorption spectrum in the infrared spectroscopic analysis of the solid, it was found that the solid was a polyphenylene sulfide mixture composed of phenylene sulfide units.

[Reference Example 3]
<Preparation of cyclic polyphenylene sulfide>
10 kg of the polyphenylene sulfide mixture obtained by the method of Reference Example 2 was collected, and 150 kg of chloroform was used as the solvent, and the mixture was stirred for 1 hour under reflux at normal pressure to bring the polyphenylene sulfide mixture into contact with the solvent. Subsequently, solid-liquid separation was performed by hot filtration to obtain an extract. After adding 150 kg of chloroform to the solid matter separated here and stirring for 1 hour under reflux at normal pressure, solid-liquid separation was similarly performed by hot filtration to obtain an extract, which was mixed with the previously obtained extract. . The obtained extract was in the form of a slurry partially containing solid components at room temperature.

  By treating this extract slurry under reduced pressure, a portion of chloroform was distilled off until the weight of the extract reached about 40 kg to obtain a slurry. Next, this slurry mixture was added dropwise to 600 kg of methanol with stirring. The resulting precipitate was filtered to recover the solid content, and then dried under reduced pressure at 80 ° C. to obtain 3.0 kg of white powder.

  From the absorption spectrum in the infrared spectroscopic analysis of this white powder, it was confirmed that the white powder was a compound composed of phenylene sulfide units. In addition, mass spectrum analysis (device: Hitachi M-1200H) of components separated from high performance liquid chromatography (device; Shimadzu LC-10, column; C18, detector; photodiode array), MALDI-TOF From the molecular weight information by -MS, it was found that this white powder was a mixture mainly composed of cyclic polyphenylene sulfide having 4 to 12 repeating units, and the weight fraction of cyclic polyphenylene sulfide was about 94%. Moreover, as a result of performing GPC measurement of this mixture, the weight average molecular weight was 900.

[Reference Example 4]
<Preparation of granular polyphenylene sulfide>
Here, preparation of polyphenylene sulfide obtained by a conventional method is shown.

  About 100 kg of NMP was added to 100 kg of the granular polyphenylene sulfide containing the slurry obtained in Reference Example 1, washed at 85 ° C. for 30 minutes, and filtered through a sieve (80 mesh, opening of 0.175 mm). The obtained solid was diluted with 500 kg of ion-exchanged water, stirred at 70 ° C. for 30 minutes, filtered through an 80-mesh sieve, and the operation of collecting the solid was repeated 5 times in total. The solid material thus obtained was dried at 130 ° C. in a nitrogen atmosphere to obtain granular polyphenylene sulfide.

  The obtained granular polyphenylene sulfide was completely dissolved in 1-chloronaphthalene at 210 ° C. As a result of GPC measurement, the weight average molecular weight was 48,600, and the degree of dispersion was 2.66. As a result of measuring the weight loss rate during heating of the obtained product, ΔWr was 0.230%. Furthermore, as a result of analyzing the generated gas component at the time of heating for the polyphenylene sulfide obtained here, 618 ppm of γ-butyrolactone and 416 ppm of 4-chloro-N-methylaniline were detected with respect to the weight of the polyphenylene sulfide before heating. It was. As a result of measuring the melting point and the cooling crystallization temperature using a differential scanning calorimeter, the melting point was 280 ° C. and the cooling crystallization temperature was 177 ° C. Moreover, solidification temperature was 241 degreeC as a result of the solidification temperature measurement using the viscoelasticity measuring apparatus.

[Reference Example 5]
<Preparation of sulfide compound (Q)>
Here, a method for preparing the sulfide compound represented by the following formula (Q) will be described. Weigh 2.18 g (0.01 mol) of bis (4-hydroxyphenyl) sulfide and 0.81 g (0.02 mol) of sodium hydroxide in a 200 mL beaker, add a stirrer chip and 50 g of ion-exchanged water, and add magnetic. Stirring was started with a stirrer and it was confirmed that a transparent aqueous solution was obtained. The total amount of calcium propionate aqueous solution prepared by dissolving 7.45 g (0.04 mol) of calcium propionate in 50 g of ion-exchanged water was added dropwise over 10 minutes, and stirring was continued for 30 minutes after completion of the addition. At this time, compound (Q) was produced, and a white precipitate was formed in the aqueous solution. The precipitate was collected by filtration, washed 3 times with 50 g of ion exchange water, and then vacuum dried at 70 ° C. for 10 hours to obtain 1.69 g of a white solid. As a result of infrared spectroscopic analysis of this white solid, the disappearance of the peak derived from OH stretching vibration around 3300 cm ⁻¹ observed in the raw material bis (4-hydroxyphenyl) sulfide was confirmed. In addition, the weight of calcium carbonate obtained by thermally decomposing white solid in an electric furnace at 550 ° C. for 5 hours is 44.5% based on the weight before pyrolysis, and is based on the molecular weight of compound (Q). Since it was close to the required theoretical value of 45.2%, it was suggested that the main component of the white solid was the compound (Q).

[Reference Example 6]
<Preparation of sulfide compound (R)>
Here, a method for preparing the sulfide compound represented by the following formula (R) will be described. Weigh out 3.06 g (0.01 mol) of 5,5′-thiodisalicylic acid and 1.60 g (0.04 mol) of sodium hydroxide in a 200 mL beaker, add a stirrer chip and 50 g of ion-exchanged water, and add magnetic. Stirring was started with a stirrer and it was confirmed that a transparent aqueous solution was obtained. The total amount of calcium acetate aqueous solution prepared by dissolving 14.1 g (0.08 mol) of calcium acetate monohydrate in 50 g of ion-exchanged water was added dropwise over 10 minutes, and stirring was continued for 30 minutes after completion of the addition. It was. At this time, compound (R) was produced, and a white precipitate was formed in the aqueous solution. The precipitate was collected by filtration, washed three times with 50 g of ion exchange water, and then vacuum dried at 70 ° C. for 10 hours to obtain 1.72 g of a white solid. As a result of infrared spectroscopic analysis of this white solid, the disappearance of the peak derived from OH stretching vibration in the vicinity of 3100 cm ⁻¹ observed in 5,5′-thiodisalicylic acid as a raw material was confirmed. In addition, the weight of calcium carbonate obtained by thermally decomposing white solid by heating at 550 ° C. for 5 hours in an electric furnace is 51.2% on the basis of the weight before pyrolysis, and is based on the molecular weight of compound (R). Since the obtained theoretical value was close to 52.3%, it was suggested that the main component of the white solid was the compound (R).

[Example 1]
4.00 g of the cyclic polyphenylene sulfide obtained in Reference Example 3 and 164 mg of the compound (Q) obtained in Reference Example 5 (1 mol% based on the sulfur atom in the cyclic polyphenylene sulfide) were stirred with a stirring blade, a vacuum adapter, After putting in a vacuum stirrer and a test tube equipped with a nitrogen introduction tube and depressurizing the system, the operation under a nitrogen atmosphere was repeated three times. The mixture was kept at 340 ° C. for 5 hours while stirring under reduced pressure, and then the stirring was stopped and the mixture was allowed to cool to obtain a polymer. The obtained polymer was found to have a polyphenylene sulfide structure from the absorption spectrum obtained by infrared spectroscopy. Further, GPC measurement of the obtained polyphenylene sulfide revealed a weight average molecular weight of 62,000 and a polydispersity index of 2.30. Moreover, as a result of measuring the weight decreasing rate at the time of the heating of the obtained polyphenylene sulfide, (DELTA) Wr was 0.070%. Furthermore, as a result of analyzing the gas components generated during heating of the polyphenylene sulfide obtained here, the lactone type compound and the aniline type compound were below the detection limit. As a result of measuring the melting point and the cooling crystallization temperature using a differential scanning calorimeter, the melting point was 279 ° C. and the cooling crystallization temperature was 183 ° C. Moreover, the solidification temperature was 220 degreeC as a result of the solidification temperature measurement using the viscoelasticity measuring apparatus.

[Example 2]
Example except that 4.00 g of the cyclic polyphenylene sulfide obtained in Reference Example 3 and 141 mg of the compound (R) obtained in Reference Example 6 (1 mol% based on the sulfur atom in the cyclic polyphenylene sulfide) were used. In the same manner as in Example 1, a polymer was obtained. The obtained polymer was found to have a polyphenylene sulfide structure from the absorption spectrum obtained by infrared spectroscopy. Further, GPC measurement of the obtained polyphenylene sulfide revealed that the weight average molecular weight was 59,800 and the polydispersity index was 2.37. Moreover, as a result of measuring the weight loss rate at the time of the heating of the obtained polyphenylene sulfide, (DELTA) Wr was 0.096%. Furthermore, as a result of analyzing the gas components generated during heating of the polyphenylene sulfide obtained here, the lactone type compound and the aniline type compound were below the detection limit. As a result of measuring the melting point and the cooling crystallization temperature using a differential scanning calorimeter, the melting point was 280 ° C. and the cooling crystallization temperature was 194 ° C. Moreover, solidification temperature was 226 degreeC as a result of the solidification temperature measurement using the viscoelasticity measuring apparatus.

[Example 3]
4.00 g of the cyclic polyphenylene sulfide obtained in Reference Example 3 and 14.1 mg of the compound (R) obtained in Reference Example 6 (0.1 mol% with respect to the sulfur atom in the cyclic polyphenylene sulfide) were used. Except for the above, a polymer was obtained in the same manner as in Example 1. The obtained polymer was found to have a polyphenylene sulfide structure from the absorption spectrum obtained by infrared spectroscopy. Further, GPC measurement of the obtained polyphenylene sulfide revealed a weight average molecular weight of 63,800 and a polydispersity index of 2.40. Moreover, as a result of measuring the weight decreasing rate at the time of the heating of the obtained polyphenylene sulfide, (DELTA) Wr was 0.067%. Furthermore, as a result of analyzing the gas components generated during heating of the polyphenylene sulfide obtained here, the lactone type compound and the aniline type compound were below the detection limit. As a result of measuring the melting point and the cooling crystallization temperature using a differential scanning calorimeter, the melting point was 279 ° C. and the cooling crystallization temperature was 211 ° C. Moreover, the solidification temperature was 237 degreeC as a result of the solidification temperature measurement using the viscoelasticity measuring apparatus.

[Comparative Example 1]
A polymer was obtained in the same manner as in Example 1 except that 4.00 g of the cyclic polyphenylene sulfide obtained in Reference Example 3 was used, no additive was added, and the retention time was 6 hours. The obtained polymer was found to have a polyphenylene sulfide structure from the absorption spectrum obtained by infrared spectroscopy. Further, GPC measurement of the obtained polyphenylene sulfide revealed that the weight average molecular weight was 58,900 and the dispersity was 2.33. Moreover, as a result of measuring the weight decreasing rate at the time of the heating of the obtained polyphenylene sulfide, (DELTA) Wr was 0.041%. Furthermore, as a result of analyzing the generated gas component at the time of heating about the PPS resin composition obtained here, the lactone type compound and the aniline type compound were below the detection limit. As a result of measuring the melting point and the cooling crystallization temperature using a differential scanning calorimeter, the melting point was 280 ° C. and the cooling crystallization temperature was 227 ° C. Moreover, the solidification temperature was 250 degreeC as a result of the solidification temperature measurement using the viscoelasticity measuring apparatus.

[Comparative Example 2]
Example 1 was repeated except that 4.00 g of the cyclic polyphenylene sulfide obtained in Reference Example 3 and 70.6 mg of sodium 4-chlorophenylacetate (1 mol% based on the sulfur atom in the cyclic polyphenylene sulfide) were used. As a result, a polymer was obtained. The obtained polymer was found to have a polyphenylene sulfide structure from the absorption spectrum obtained by infrared spectroscopy. Further, as a result of GPC measurement of the obtained polyphenylene sulfide, the weight average molecular weight was 53,200, and the degree of dispersion was 2.43. Moreover, as a result of measuring the weight decreasing rate at the time of the heating of the obtained polyphenylene sulfide, (DELTA) Wr was 0.054%. Furthermore, as a result of analyzing the gas components generated during heating of the polyphenylene sulfide obtained here, the lactone type compound and the aniline type compound were below the detection limit. As a result of measuring the melting point and the cooling crystallization temperature using a differential scanning calorimeter, the melting point was 280 ° C. and the cooling crystallization temperature was 228 ° C. Moreover, the solidification temperature was 250 degreeC as a result of the solidification temperature measurement using the viscoelasticity measuring apparatus.

[Comparative Example 3]
Using 4.00 g of the cyclic polyphenylene sulfide obtained in Reference Example 3 and 80.7 mg of bis (4-hydroxyphenyl) sulfide (1 mol% based on the sulfur atom in the cyclic polyphenylene sulfide), the retention time was 3 hours. A polymer was obtained in the same manner as in Example 1 except that. The obtained polymer was found to have a polyphenylene sulfide structure from the absorption spectrum obtained by infrared spectroscopy. Further, GPC measurement of the obtained polyphenylene sulfide revealed that the weight average molecular weight was 25,800 and the dispersity was 2.08. Moreover, as a result of measuring the weight decreasing rate at the time of the heating of the obtained polyphenylene sulfide, (DELTA) Wr was 0.108%. Furthermore, as a result of analyzing the generated gas component at the time of heating about the PPS resin composition obtained here, the lactone type compound and the aniline type compound were below the detection limit. As a result of measuring the melting point and the cooling crystallization temperature using a differential scanning calorimeter, the melting point was 280 ° C. and the cooling crystallization temperature was 229 ° C. Moreover, solidification temperature was 249 degreeC as a result of the solidification temperature measurement using the viscoelasticity measuring apparatus.

[Comparative Example 4]
Except for using 4.00 g of the cyclic polyphenylene sulfide obtained in Reference Example 3 and 48.9 mg of thiophenol sodium salt (1 mol% with respect to the sulfur atom in the cyclic polyphenylene sulfide), the retention time was 3 hours. A polymer was obtained in the same manner as in Example 1. The obtained polymer was found to have a polyphenylene sulfide structure from the absorption spectrum obtained by infrared spectroscopy. Further, GPC measurement of the obtained polyphenylene sulfide revealed that the weight average molecular weight was 28,700 and the degree of dispersion was 2.28. Moreover, as a result of measuring the weight decreasing rate at the time of the heating of the obtained polyphenylene sulfide, (DELTA) Wr was 0.251%. Furthermore, as a result of analyzing the generated gas component at the time of heating about the PPS resin composition obtained here, the lactone type compound and the aniline type compound were below the detection limit. As a result of measuring the melting point and the cooling crystallization temperature using a differential scanning calorimeter, the melting point was 280 ° C. and the cooling crystallization temperature was 218 ° C. Moreover, as a result of the solidification temperature measurement using the viscoelasticity measuring apparatus, the solidification temperature was 241 ° C. The above results are shown in Table 1.

  From comparison between Examples 1 to 3 and Reference Example 4 in Table 1, it is clear that polyarylene sulfide satisfying a polydispersity index of 2.5 or less can be obtained by using a method of heating cyclic polyarylene sulfide. It is.

  Further, from the comparison between Examples 1 to 3 in Table 1 and Comparative Example 4 and Reference Example 4, a method of heating cyclic polyarylene sulfide was used, and a gas of a polymer obtained such as thiophenol sodium salt was used. It is clear that by using no additive that increases the generation amount, polyarylene sulfide that satisfies ΔWr of 0.18% or less and that generates a small amount of gas during heating can be obtained.

  Furthermore, from the comparison of Examples 1 to 3 and Comparative Examples 1 to 4 in Table 1, by heating the cyclic polyarylene sulfide in the presence of the sulfide compound of the present invention, the cooling crystallization temperature satisfies 220 ° C. or lower. It is apparent that a polyarylene sulfide having a lowered temperature-falling crystallization temperature and a reduced solidification temperature that satisfies a solidification temperature of 240 ° C. or lower can be obtained.

Claims (7)

The cyclic polyarylene sulfide (a) is 0.1 mol% to 10 mol% of the sulfide compound (b) represented by the following formula (B1) or (B2) with respect to the sulfur atom in the cyclic polyarylene sulfide. A process for producing polyarylene sulfide (c), which is heated in the presence;

S is a sulfur atom, X and Y are, -O -, - S -, - CO 2 -, - SO 3 - either, M is an alkaline earth metal, Z is located at the carboxyl group having 1 to 3 carbon atoms , L and m each represents an integer of 0 or 1. The cyclic polyarylene sulfide (a) contains at least 50% by weight or more of the cyclic compound represented by the following formula (A), and the repeating number n in the formula is 4 to 50. Production method of polyarylene sulfide (c);

Ar represents an arylene group. The method for producing polyarylene sulfide (c) according to claim 1 or 2, wherein the heating is carried out in the absence of a solvent. The polyarylene sulfide (c) obtained has a weight average molecular weight of 10,000 or more and a polydispersity index expressed by weight average molecular weight / number average molecular weight of 2.5 or less. The manufacturing method of the polyarylene sulfide (c) in any one. The method for producing a polyarylene sulfide (c) according to any one of claims 1 to 4, wherein the weight loss when the obtained polyarylene sulfide (c) is heated satisfies the following formula.
ΔWr = (W ₁₀₀ −W ₃₃₀ ) / W ₁₀₀ × 100 ≦ 0.18 (%)
ΔWr is a weight loss rate, and when thermogravimetric analysis was performed at a temperature rising rate of 20 ° C./min from 50 ° C. to an arbitrary temperature of 330 ° C. or higher in a non-oxidizing atmosphere at normal pressure, when the temperature reached 100 ° C. This is a value obtained from the sample weight (W ₁₀₀ ) and the sample weight (W ₃₃₀ ) when reaching 330 ° C. Formula (B1) or (B2) X and Y contained in the sulfide compound (b) represented by the -O -, - CO ₂ - polyarylene according to any of claims 1 to 5 is either A method for producing sulfide (c). The method for producing a polyarylene sulfide (c) according to any one of claims 1 to 6, wherein the alkaline earth metal contained in the sulfide compound (b) represented by the formula (B1) or (B2) is calcium.