JPH08157600A - Production of polyarylene sulfide excellent in adhesive properties - Google Patents

Abstract

PURPOSE: To provide a process for producing a polyarylene sulfide resin compsn. excellent in heat resistance, mechanical strengths, and adhesion to an epoxy resin, etc. CONSTITUTION: A polyarylene sulfide is produced by reacting an alkali metal sulfide with a dihaloarom. component in an org. amide solvent under such conditions that: the dihaloarom. component comprises 99.5-90mol% p-dihaloarom. compd. and 0.5-10mol% m-dihaloarom. compd., the latter compd. being added to the reaction system when the conversion of the former compd. in the system is 0--80%; during the reaction a part of the vapor phase in the reactor is cooled, condensed, and returned to the liq. phase; and the resulting polyarylene sulfide is washed with water and treated with an acid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing polyarylene sulfide (hereinafter sometimes abbreviated as PAS), and more specifically, a method for producing PAS excellent in adhesiveness with a thermoplastic resin such as epoxy resin. Regarding

[0002]

2. Description of the Related Art PAS is widely used for electric / electronic parts or mechanical parts because it has excellent heat resistance and molding processability and further has good chemical resistance, flame retardancy and dimensional stability. . However, PAS has relatively poor adhesiveness with other resins, especially with epoxy resin. Therefore, for example, when the PASs are bonded to each other with an epoxy adhesive, the PASs are bonded to another material, or the electric / electronic components are sealed with an epoxy resin, poor adhesion between the PAS and the epoxy resin is a problem. It was.

In view of such problems, various attempts have been made to improve the adhesion between PAS and epoxy resin. For example, JP-A-2-272063 discloses a polyphenylene sulfide (hereinafter sometimes abbreviated as PPS) resin composition containing carnauba wax, JP-A-4-275368.
Japanese Patent Laid-Open No. 5-1711041 discloses a PPS resin composition prepared by mixing a fibrous and / or non-fibrous filler with a polyalkylene ether compound, and Japanese Patent Laid-Open No. 5-171041 discloses a super absorbent polymer such as a crosslinked polyacrylate. A PPS resin composition containing, an aromatic sulfone compound in JP-A-6-57136,
And P containing a fibrous and / or non-fibrous filler
PS resin composition, JP-A-6-107946 discloses a PPS resin composition containing an aliphatic polyester, and a fibrous and / or non-fibrous filler, and JP-A-6-107946.
No. 166816 discloses a P containing a poly (ethylenecyclohexanedimethylene terephthalate) copolymer.
Each PS resin composition is disclosed. However, in any of the above, the addition of a substance having a lower heat resistance than PPS has resulted in a decrease in the heat resistance of the resin composition and, in some resin compositions, a marked decrease in the mechanical strength.

Further, JP-A-4-198267 discloses a PAS resin composition containing a PAS containing a carboxyl group, and JP-A-5-25388 discloses a PAS resin composition containing a PAS containing an amino group. ing. However, these are produced, for example, by copolymerizing dichlorobenzene having a carboxyl group or an amino group, but there is a production problem that these dichlorobenzenes remain in the reaction system, and adhesion of the obtained PAS It was not strong enough.

[0005]

The present invention is based on the conventional PA.
The present invention provides a method for producing a PAS resin composition having excellent heat resistance and mechanical strength of S as well as excellent adhesiveness with an epoxy resin or the like.

[0006]

The present invention relates to a method for producing a polyarylene sulfide by reacting an alkali metal sulfide with a dihalo aromatic compound in an organic amide solvent, wherein the para dihalo aromatic compound and the reaction system are used. When the reaction rate of the paradihaloaromatic compound is 0 to less than 80%, 0.5 to 10 mol% of the metadihaloaromatic compound is added to the reaction system with respect to the total amount of the charged dihaloaromatic compound, and during the reaction, It is characterized in that the polyarylene sulfide obtained by condensing a part of the gas phase in the reaction can by cooling the gas part of the reaction can and refluxing it in the liquid phase is washed with water and treated with an acid. A method for producing a polyarylene sulfide having excellent adhesiveness.

In the present invention, it was unexpected that adhesion would be significantly improved without the need to add a third substance or functional group as in the prior art.

In the para and metadihaloaromatic compounds added in the present invention, the lower limit of the amount of the metadihaloaromatic compound is 0.5 mol%, preferably 1 mol%, and the upper limit of the total amount of the charged dihaloaromatic compounds. Is 10 mol%, preferably 5.0 mol%. If it is less than the above range, the adhesiveness of the produced PAS is inferior, and if it exceeds the above range, the melting point of the produced PAS is remarkably lowered, the heat resistance which is the original property of PAS is impaired, and there is a problem in practicality. It is not preferred.

The metadihaloaromatic compound is added when the reaction rate of the paradihaloaromatic compound in the reaction system is 0 to less than 80%. The reaction rate of paradihalo aromatic compounds is 8
When it is 0% or more, the adhesiveness of the produced PAS is poor, the viscosity is lowered, and the metadihaloaromatic compound remains unreacted in the reaction system, which is not preferable. Preferably the para and metadihalo aromatic compounds are added to the reaction system simultaneously. Thus, by simultaneously adding both of them, the adhesiveness of PAS can be further improved. The total amount of para and metadihalo aromatic compounds added to the polymerization reaction system is based on 1 mol of the alkali metal sulfide.
Preferably 0.9 to 1.1 moles, particularly preferably 0.9
It is 6 to 1.05 mol. By using within this range, high molecular weight PAS can be obtained. If the amount added is less than the above range, only PAS having a remarkably low molecular weight can be obtained, and the reaction rates of the para and metadihalo aromatic compounds decrease, which is economically disadvantageous. If it exceeds the above range, depolymerization occurs, which is not preferable. When the metadihaloaromatic compound is charged during the reaction, for example, the metadihaloaromatic compound is directly or dissolved in N-methylpyrrolidone or the like used as an organic amide solvent, and a reaction vessel using a pressure injection pump is used. It can be performed by press-fitting the inside.

The para and metadihaloaromatic compounds used in the method of the present invention are known. For example, it can be selected from those described in JP-B-45-3368, JP-A-2-103232, or JP-B-4-64618.

Examples of the paradihaloaromatic compound include dihalogenated benzenes such as p-dichlorobenzene, p-dibromobenzene and 1-chloro-4-bromobenzene.
Alternatively, 2,5-dichlorotoluene, 2,5-dichloroxylene, 1-ethyl-2,5-dichlorobenzene, 1
-Ethyl-2,5-dibromobenzene, 1-ethyl-2
-Bromo-5-chlorobenzene, 1,3,4,6-tetramethyl-2,5-dichlorobenzene, 1-cyclohexyl-2,5-dichlorobenzene, 1-phenyl-2
5-dichlorobenzene, 1-benzyl-2,5-dichlorobenzene, 1-phenyl-2,5-dibromobenzene, 1-p-toluyl-2,5-dichlorobenzene, 1
Examples thereof include substituted dihalogenated benzenes such as -p-toluyl-2,5-dibromobenzene and 1-hexyl-2,5-dichlorobenzene. Of the above, dihalogenated benzene is preferable, and of these, p-dichlorobenzene is particularly preferable. Moreover, these compounds can be used individually or as a mixture.

Examples of the metadihalo aromatic compound include dihalogenated benzenes such as m-dichlorobenzene, m-dibromobenzene and 1-chloro-3-bromobenzene.
Alternatively, 2,4-dichlorotoluene, 2,4-dichloroxylene, 1-ethyl-2,4-dibromobenzene, 1
-Ethyl-2-bromo-4-chlorobenzene, 1,2,
4,6-Tetramethyl-3,5-dichlorobenzene, 1
-Cyclohexyl-2,4-dichlorobenzene, 1-phenyl-2,4-dichlorobenzene, 1-benzyl-
2,4-dichlorobenzene, 1-phenyl-2,4-dibromobenzene, 1-p-toluyl-2,4-dichlorobenzene, 1-p-toluyl-2,4-dibromobenzene, 1-hexyl- Substituted dihalogenated benzene such as 2,4-dichlorobenzene and the like can be mentioned. Of the above, dihalogenated benzene is preferable, and of these, m-dichlorobenzene is particularly preferable. These compounds can be used individually or as a mixture.

A method for condensing a part of the gas phase in the reaction vessel by cooling the gas phase portion of the reaction vessel of the present invention and returning it to the liquid phase is described in JP-A-5-222196. Can be used.

The refluxed liquid has a high water content compared to the liquid phase bulk because of the vapor pressure difference between water and the amide solvent.
This reflux liquid having a high water content forms a layer having a high water content on the reaction solution. As a result, the residual alkali metal sulfide (for example, Na ₂ S), alkali metal halide (for example, NaCl), oligomer and the like are contained in a large amount in the layer. In the conventional method, at a high temperature of 230 ° C. or higher, when the generated PAS and the raw materials such as Na ₂ S and by-products are uniformly mixed, not only high-molecular-weight PAS cannot be obtained but Depolymerization of PAS also occurred, and thiophenol by-product was observed. However, in the present invention, by positively cooling the gas phase portion of the reaction vessel and returning a large amount of water-rich reflux liquid to the upper portion of the liquid phase, the above-mentioned inconvenient phenomenon can be avoided and the reaction is inhibited. Of high molecular weight PA
It seems that S can be obtained. However, the present invention is not limited only to the effects due to the above-mentioned phenomenon, and high-molecular weight PAS can be obtained by various influences caused by cooling the gas phase portion.

In the present invention, it is not necessary to add water during the reaction unlike the conventional method. However, the addition of water is not excluded at all. However, some of the advantages of the present invention are lost if the operation of adding water is performed. Therefore, preferably, the total water content in the polymerization reaction system is constant throughout the reaction.

The gas phase portion of the reaction can can be cooled by external cooling or internal cooling, and can be performed by a cooling means known per se. For example, a method of flowing a cooling medium into an internal coil installed in the upper part of the reaction can, a method of flowing a cooling medium into an external coil or jacket wound around the upper part of the outside of the reaction can, and a reflux condenser installed in the upper part of the reaction can are used. The method may be such as sprinkling water or blowing gas (air, nitrogen, etc.) on the upper part of the outside of the reaction can. Any method is effective as long as it has the effect of increasing the reflux amount in the can. May be used. If the outside air temperature is relatively low (for example, room temperature), it is also possible to perform appropriate cooling by removing the heat insulating material conventionally provided on the upper part of the reaction can. In the case of external cooling, water condensed on the reactor wall surface
The amide-based solvent mixture enters the liquid phase along the wall of the reaction vessel. Thus, the water-rich mixture pools on top of the liquid phase,
Keep the water content there relatively high. For internal cooling,
The mixture condensed on the cooling surface likewise travels along the surface of the cooling device or the wall of the reaction vessel into the liquid phase.

On the other hand, the temperature of the liquid phase bulk is maintained at a predetermined constant temperature or controlled according to a predetermined temperature profile. 230 to 275 for constant temperature
It is preferable to carry out the reaction at a temperature of ° C for 0.1 to 20 hours. More preferably, the temperature is 240 to 265 ° C. and the time is 1 to 6 hours. To obtain higher molecular weight PAS, it is preferable to use a reaction temperature profile of two or more steps. This 2
When carrying out the stepwise operation, the first step is preferably carried out at a temperature of 195 to 240 ° C. If the temperature is low, the reaction rate is too slow, which is not practical. If the temperature is higher than 240 ° C., the reaction rate is too fast, PAS having a sufficiently high molecular weight cannot be obtained, and the side reaction rate remarkably increases. The end of the first stage is
Dihalo aromatic compound residual rate in the polymerization reaction system is 1 mol% to 40
It is preferable to carry out at a time of mol% and a molecular weight in the range of 3,000 to 20,000. More preferably, the residual ratio of the dihalo-aromatic compound in the polymerization reaction system is 2 mol% to 15 mol% and the molecular weight is 5,000 to 15,000. Residual rate is 40 mol%
When it is more than 1, the side reaction such as depolymerization is likely to occur in the second step reaction, while when it is less than 1 mol%, the high molecular weight P is finally obtained.
It is difficult to get AS. Thereafter, the temperature is raised, and the reaction in the final stage is preferably carried out at a reaction temperature of 240 to 270 ° C. for 1 to 10 hours. PAS with sufficiently high molecular weight at low temperature
At a temperature higher than 270 ° C., side reactions such as depolymerization are likely to occur, making it difficult to stably obtain a high molecular weight product.

As a practical operation, first, dehydration or water addition is carried out in an inert gas atmosphere so that the amount of water in the alkali metal sulfide in the amide solvent becomes a predetermined amount, if necessary. The water content is preferably alkali metal sulfide 1
The amount is 0.5 to 2.5 mol, especially 0.8 to 1.2 mol per mol. If it exceeds 2.5 mols, the reaction rate will be low, and the amount of by-products such as phenol will increase in the filtrate after the reaction and the degree of polymerization will not increase. If it is less than 0.5 mol, the reaction rate is too fast to obtain a sufficiently high molecular weight product, and unfavorable reactions such as side reactions occur.

In the case of the one-step reaction at a constant temperature, the cooling of the gas phase portion during the reaction is preferably performed from the start of the reaction, but it must be performed at least during the temperature increase of 250 ° C. or less. In the multi-stage reaction, it is preferable to perform cooling from the first-stage reaction, but it is preferable to perform cooling at the latest after the completion of the first-stage reaction. Regarding the degree of cooling effect, the pressure inside the reaction vessel is usually the most suitable index. The absolute value of the pressure varies depending on the characteristics of the reaction vessel, the stirring state, the water content in the system, the molar ratio of the dihalo aromatic compound to the alkali metal sulfide, and the like. However, as compared with the case of not cooling under the same reaction conditions, if the reactor pressure is decreased, the amount of reflux liquid is increased, which means that the temperature at the reaction solution gas-liquid interface is decreased. It is considered that the degree of relative decrease indicates the degree of separation between the layer having a high water content and the layer having no water content. Therefore, it is preferable to cool the reactor so that the internal pressure of the reactor becomes lower than that in the case where no cooling is performed. The degree of cooling can be appropriately set by those skilled in the art according to the equipment used, operating conditions, and the like.

PAS having a desired viscosity can be produced by variously selecting the above reaction conditions.

The organic amide solvent used here is PA
Known for S polymerization, for example N-methylpyrrolidone (NMP), N, N-dimethylformamide,
N, N-dimethylacetamide, N-methylcaprolactam, etc., and mixtures thereof can be used, with NMP being preferred. They all have a lower vapor pressure than water.

Alkali metal sulfides used in the present invention are also known, such as lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, cesium sulfide and mixtures thereof. These hydrates and aqueous solutions may be used. Further, hydrosulfides and hydrates corresponding to these can be used after being neutralized with the corresponding hydroxides. Inexpensive sodium sulfide is preferred.

In order to increase the molecular weight of PAS,
For example, 1,3,5-trichlorobenzene, 1,2,4-
A polyhalo compound such as trichlorobenzene can also be used in a concentration of preferably 5 mol% or less based on the total amount of para and metadihalo aromatic compounds.

Further, as a small amount of other additives, a terminal terminating agent and a monohalo compound as a modifying agent can be used in combination.

In the present invention, the PAS obtained in the above step is washed with water and treated with acid.

Washing with water is preferably carried out by filtering the slurry produced in the PAS manufacturing process and then dispersing the filter cake in water. For example, the PAS slurry obtained as described above is filtered to obtain a PAS cake containing little solvent. The PAS cake is put into water preferably 1 to 5 times by weight, preferably at room temperature to 9
After stirring and mixing at 0 ° C., preferably for 5 minutes to 10 hours,
Filter. The stirring and mixing and filtering operations are preferably 2-1
By repeating 0 times, the solvent adhering to PAS and the by-product salt are removed, and the washing with water is completed. By performing water washing as described above, it becomes possible to perform efficient washing with a small amount of water as compared with the washing method in which water is poured into the filter cake.

The acid treatment is preferably carried out at a temperature of 100 ° C. or lower, particularly preferably at room temperature to 80 ° C.
If the temperature exceeds the above upper limit, the PAS molecular weight after acid treatment decreases, which is not preferable. The pH of the acid solution used for the acid treatment is preferably 3.5 to 6.0, particularly preferably 4.0 to 5.5. By adopting the pH, most of -SNa terminal in PAS which is the object to be treated can be converted to -SH terminal. If the pH is less than the above range, the amount of acid used is large and the cost becomes high. If the pH exceeds the above range, the removal of the Na terminal in PAS becomes insufficient.
The time required for the acid treatment depends on the acid treatment temperature and the concentration of the acid solution, but it is preferably 5 minutes or longer, particularly preferably 10 minutes or longer. Below the above, in PAS-
It is not preferable since the SNa terminal cannot be sufficiently converted to the -SH terminal. Examples of the acid treatment include acetic acid, formic acid, oxalic acid, phthalic acid, hydrochloric acid, phosphoric acid, sulfuric acid, sulfurous acid, nitric acid, boric acid,
Carbonic acid or the like is used, with acetic acid being particularly preferred. By carrying out the treatment, sodium as an impurity in PAS can be reduced.

By performing the above-mentioned washing with water and acid treatment, the amount of sodium in PAS can be remarkably reduced. This improves the dimensional stability of the molded product and also increases the adhesive strength.

The PAS produced by the method of the present invention is
Since rapid crystallization does not proceed, it is possible to suppress the occurrence of cracks due to molding shrinkage and the like, and it has high adhesiveness with a thermoplastic resin such as an epoxy resin. Therefore, it is useful in the field of sealing electric / electronic parts.

When the PAS of the present invention is molded and processed, conventional additives such as powdered fillers such as carbon black, calcium carbonate, silica and titanium oxide, or carbon fibers, glass fibers, asbestos fibers, polyaramid fibers are used. Fibrous fillers such as can be mixed.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0032]

EXAMPLES In the examples, the melt viscosity V ₆ was 300 using a flow tester CFT-500C manufactured by Shimadzu Corporation.
It is a viscosity (poise) measured after holding for 6 minutes at L / D = 10 at a temperature of 20 kgf / cm ² and a load of 20 kgf / cm ² .

According to DSC, the crystallization temperature T _c and the melting point T
_m was measured. As an apparatus, a differential scanning calorimeter SSC / 5200 manufactured by Seiko Instruments Inc. was used, and measurement was performed as follows. 10 mg of the sample was heated from room temperature to 320 ° C. at a heating rate of 20 ° C./min in a nitrogen stream, and then held at 320 ° C. for 5 minutes to melt. It was then cooled at a rate of 10 ° C / min. The exothermic peak temperature at this time was defined as the crystallization temperature _Tc . The endothermic peak temperature when the temperature was raised from room temperature to 320 ° C. at a rate of 10 ° C./min was defined as the melting point T _m .

Paradichlorobenzene (hereinafter p-DC
The reaction rates of B) and metadichlorobenzene (hereinafter sometimes abbreviated as m-DCB) were calculated from the measurement results by gas chromatography. Here, each reaction rate was calculated by the following formula.

[0035]

## EQU1 ## Reaction rate (%) of p-DCB = (1-remaining p-D
CB weight / p-DCB weight) × 100

[0036]

## EQU2 ## Reaction rate (%) of m-DCB = (1-remaining m-D
CB weight / prepared m-DCB weight) × 100 The adhesive strength was measured as follows. Glass fiber (CS 3J-961S, trademark,
40 parts by weight (manufactured by Nitto Boseki Co., Ltd.) were mixed and then kneaded at 320 ° C. using a twin-screw counter-rotating extruder to prepare pellets. From the pellets obtained, the cylinder temperature is 32
With an injection molding machine set to 0 ℃ and mold temperature 130 ℃,
A test piece according to JIS K6850 was prepared. JIS
According to K6850, the obtained test piece was treated with an epoxy resin adhesive [manufactured by Nagase Ciba Co., Ltd., main agent (XNR3101,
(Trademark) / curing agent (XNH3101, trademark) = 100 parts by weight / 33.3 parts by weight] at 90 ° C. for 30 minutes for curing, and then a tensile test at a pulling speed of 5 mm / minute and a chuck distance of 130 mm. Then, the adhesive strength was measured.

[0037]

Example 1 Flake-shaped sodium sulfide (60.4 wt% Na ₂ S) 19.38 was placed in a 150 liter autoclave.
1 kg and N-methyl-2-pyrrolidone (hereinafter NM
45.0 kg was charged. While stirring under a nitrogen stream, the temperature was raised to 209 ° C. and water was reduced to 4.640
kg was distilled (the residual water content was 1.12 mol per mol of sodium sulfide). Then, the autoclave was closed and cooled to 180 ° C, p-DCB21.609kg,
0.441 kg of m-DCB (2.0 mol% based on total DCB) and 18.0 kg of NMP were charged. Liquid temperature 150
The temperature was started by pressurizing to 1 kg / cm ² G with nitrogen gas at 0 ° C. The reaction was allowed to proceed while stirring at a liquid temperature of 260 ° C. for 2 hours, and the upper portion of the autoclave was cooled by watering. Next, the temperature was lowered and the cooling of the upper part of the autoclave was stopped. During cooling of the upper part of the autoclave, the liquid temperature was kept constant so as not to drop. The maximum pressure during the reaction is 8.5
It was 9 kg / cm ² G.

The resulting slurry was filtered to remove the solvent, and then the filter cake was put into warm water at about 80 ° C. (about twice the weight of the filter cake by weight) and stirred sufficiently for about 30 minutes. , Filtered. This operation of washing with water and filtration was repeated 5 times. Next, the filter cake was slurried with water at about 50 ° C., acetic acid was added to the slurry to adjust the pH to 5, and acid treatment was carried out. After the acid treatment, washing with water was repeated three times. Then, it was dried in a hot air circulation dryer at 120 ° C. for about 8 hours to obtain white powdery PPS.

The reaction rate of p-DCB is 98.4%,
The reaction rate of m-DCB was 100%.

[0040]

Example 2 21.940 kg of p-DCB, m-DC
0.110 kg of B (0.5 mol% based on total DCB)
Other than the above, the same conditions as in Example 1 were used.

The reaction rate of p-DCB is 98.9%,
The reaction rate of m-DCB was 100%.

[0042]

Example 3 p-DCB of 20.948 kg, m-DC
1.103 kg of B (5.0 mol% based on total DCB)
Other than the above, the same conditions as in Example 1 were used.

The reaction rate of p-DCB is 98.2%,
The reaction rate of m-DCB was 100%.

[0044]

Example 4 The reaction was carried out under the same conditions as in Example 1 except that the reaction was carried out at a liquid temperature of 220 ° C. for 5 hours and then at a liquid temperature of 260 ° C. for 5 hours.

The reaction rate of p-DCB is 98.7%,
The reaction rate of m-DCB was 100%.

[0046]

Example 5 The reaction was carried out under the same conditions as in Example 1 except that the reaction was carried out at a liquid temperature of 240 ° C. for 2 hours and then at a liquid temperature of 260 ° C. for 2 hours.

The reaction rate of p-DCB is 98.7%,
The reaction rate of m-DCB was 100%.

[0048]

Example 6 20.286 kg of p-DCB and m-DC
1.764 kg of B (8.0 mol% based on total DCB)
Other than the above, the same conditions as in Example 4 were used.

The reaction rate of p-DCB is 98.5%,
The reaction rate of m-DCB was 100%.

[0050]

[Comparative Example 1] 22.06 kg of p-DCB, m-DC
0.044 kg of B (0.2 mol% based on total DCB)
Other than the above, the same conditions as in Example 1 were used.

The reaction rate of p-DCB is 98.8%,
The reaction rate of m-DCB was 100%.

[0052]

[Comparative Example 2] p-DCB was added without adding m-DCB.
The conditions were the same as in Example 1 except that the weight was 2.050 kg.

The reaction rate of p-DCB was 98.8%.

[0054]

[Comparative Example 3] 19.404 kg of p-DCB, m-DC
It carried out on the same conditions as Example 1 except having set B to 2.646 kg (12.0 mol% with respect to all DCB).

The reaction rate of p-DCB is 98.5%,
The reaction rate of m-DCB was 100%.

[0056]

[Comparative Example 4] 21.609 kg of p-DCB was charged, and when the reaction temperature reached 240 ° C. (reaction rate of p-DCB was 85%), 0.441 kg of m-DCB (total DC
Example 2 was carried out under the same conditions as in Example 5, except that (2.0 mol% with respect to B) was press-fitted into the autoclave with a pressurization injection pump.

The reaction rate of p-DCB is 98.6%,
The reaction rate of m-DCB was 100%.

[0058]

Comparative Example 5 The same conditions as in Example 4 were carried out except that the upper part of the autoclave was not cooled. The maximum pressure during the reaction was 10.31 kg / cm ² G.

The reaction rate of p-DCB is 99.1%,
The reaction rate of m-DCB was 100%.

[0060]

[Comparative Example 6] The procedure of Example 1 was repeated, except that acetic acid treatment was not performed, and washing and filtration were performed 9 times.

The reaction rate of p-DCB is 98.4%,
The reaction rate of m-DCB was 100%.

The above results are shown in Table 1.

[0063]

[Table 1] In Examples 1 to 3, the amount of m-DCB added was changed within the range of the present invention. Increasing the amount of m-DCB added increases the adhesive strength. Further, both the crystallization temperature T _c and the melting point T _m decreased. Examples 4 and 5 have a two-step reaction. It was found that the adhesive strength can be increased as compared with Example 1. The melt viscosity V ₆ was increased and a higher molecular weight PPS was obtained. In Example 6, the amount of m-DCB added was increased within the scope of the present invention under the same conditions as in Example 4. As in the case of the one-step reaction, the adhesive strength increased and both T _c and T _m decreased.

On the other hand, in Comparative Examples 1 and 2, under the same conditions as in Example 1, the amount of m-DCB added was reduced to below the range of the present invention, and the amount was not added. As compared with Example 1, the adhesive strength was remarkably low in all cases. In Comparative Example 3, the amount of m-DCB added exceeded the range of the present invention under the same conditions as in Example 1. V ₆ , T _c and T _m
Was extremely low, and the original heat resistance of PAS was impaired, which was not practical. In Comparative Example 4, under the same conditions as in Example 5, m-DCB was added at a reaction rate of p-DCB of 85%. The adhesive strength was lower than that of Example 5. Comparative Example 5 was prepared under the same conditions as in Example 4,
The upper part of the autoclave was not cooled. As compared with Example 4, the adhesive strength of PPS was significantly lower. Comparative Example 6 is one in which acetic acid treatment was not carried out under the same conditions as in Example 1. The adhesive strength was significantly lower than that of Example 1.

[0065]

INDUSTRIAL APPLICABILITY The present invention provides a method for producing a PAS resin composition excellent in adhesiveness with an epoxy resin and the like in addition to the high heat resistance and mechanical strength of conventional PAS.

Claims (5)

[Claims] 1. A method for producing a polyarylene sulfide by reacting an alkali metal sulfide with a dihaloaromatic compound in an organic amide solvent, wherein the reaction rate of the paradihaloaromatic compound and the paradihaloaromatic compound in the reaction system. Is 0 to less than 80%, 0.5 to 10 mol% of metadihaloaromatic compound is added to the reaction system with respect to the total amount of charged dihaloaromatic compound, and the gas phase part of the reaction can is cooled during the reaction. The polyarylene sulfide obtained by condensing a part of the gas phase in the reaction can by refluxing it in a liquid phase is washed with water and treated with an acid, and has excellent adhesiveness. Method for producing sulfide. 2. The method according to claim 1, wherein the paradihaloaromatic compound and the metadihaloaromatic compound are simultaneously added into the reaction system. 3. The method according to claim 1, wherein 1.0 to 5.0 mol% of the metadihaloaromatic compound is added. 4. Washing with water is carried out by filtering the slurry produced in the production process of polyarylene sulfide and then dispersing the obtained filter cake in water.
The method described in any one of. 5. The method according to claim 1, wherein the acid treatment is performed with an acid solution having a pH of 3.5 to 6.0.