JPH02302436A - Method for producing polyarylene sulfide - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing polyarylene sulfide. Specifically, the present invention relates to a method for producing polyarylene sulfide that generates a small amount of gas and has a high molecular weight.

[Prior Art and its Problems] Polyarylene sulfide, typified by polyphenylene sulfide, is produced by a method as disclosed in Japanese Patent Publication No. 45-3368. That is, it is produced by a method in which p-dichlorobenzene and sodium sulfide are reacted in an organic amide scratching solvent such as N-methylpyrrolidone. The polyphenylene sulfide obtained by this method has an extremely low degree of polymerization and is not suitable for use as it is.Industrially, this low degree of polymerization is heated in air, oxidatively crosslinked, and the molecular weight is increased by three-dimensional crosslinking. It is used for practical purposes such as injection molding.

Also known is a method of obtaining polyarylene sulfide with a high degree of polymerization through a polymerization reaction using the above-mentioned raw materials.

For example, as shown in Japanese Patent Publication No. 63-33775, a high molecular weight polymer can be obtained by adding water to the system after the first stage polymerization reaction and carrying out the second stage polymerization reaction. However, the polymer obtained through this polymerization process has problems such as generating a large amount of gas during molding, leaving voids in the molded product, reducing the strength of the molded product, and cracking the molded product. It was also found that there were problems such as corrosion of the mold due to the generated gas.

In addition, it has become clear that there are problems with the viscosity quality during melting, resulting in problems such as dripping from the nozzle of the injection molding machine due to the drop in viscosity and thickening inside the injection molding machine (↓). Ta.

[Problem to be solved by the invention]

An object of the present invention is to provide a method for producing a high molecular weight polyarylene sulfide that generates a small amount of gas during molding using at least one alkali metal hydrosulfide as a sulfur source.

(Means for Solving the Problems) The present invention provides, in the production of polyarylene sulfide, (A) at least one alkali metal hydrosulfide, at least one alkali metal hydroxide, and at least one polyhaloaromatic compound. and at 1000C to 225C in the presence of at least one organic amide polar solvent at 10,1
The first step of reacting for ~50 hours, (B) adding water so that 5 to 40 parts by weight of water including hydration water is present per 100 parts by weight of the organic amide polar solvent, and at 150 ° C. A polyarylene sulfide characterized by being carried out in two steps: a second step in which the temperature is within the range of 290°C and the temperature is raised to a temperature 15°C or more higher than in the first step and the reaction is maintained for 0.5 to 20 hours. Provides a manufacturing method.

The alkali metal bisulfides used in the present invention include lithium bisulfide, sodium bisulfide, potassium bisulfide, rubidium bisulfide, cesium bisulfide, and mixtures thereof. Such an alkali metal hydrosulfide compound can be used in the form of a hydrate and/or an aqueous mixture or an anhydrous form, and there are no restrictions on the shape, and it may be in the form of crystals, flakes, or solutions. As such an alkali metal hydrosulfide compound, sodium hydrosulfide is preferable.

Examples of the alkali metal hydroxide used in the present invention include potassium hydroxide, sodium hydroxide, lithium hydroxide, rubidium hydroxide, cesium hydroxide, and mixtures thereof, with sodium hydroxide being preferred.

The amount of alkali metal hydroxide used in the present invention is usually 0.7 to 1.3 per mole of alkali metal hydrosulfide.
mol, preferably in the range of 0.9 to 1.1 mol.

The polyhaloaromatic compound used in the present invention is a halogenated aromatic compound having two or more halogen atoms directly bonded to an aromatic nucleus, and specifically, p-dichlorobenzene, m
-dichlorobenzene, 0-dichlorobenzene, trichlorobenzene, tetrachlorobenzene, dichloronaphthalene, trichloronaphthalene, dibromobenzene, trichlorobenzene, dibromonaphthalene, dichlorobenzene, triiodobenzene, dichlorodiphenylsulfone,
Examples thereof include dibromidiphenyl sulfone, dichlorhensiphenone, dibrombenzophenone, dichlordiphenyl ether, dibromidiphenyl ether, dichlordiphenyl sulfide, dibromidiphenyl sulfide, dichlorbiphenyl, dibrombiphenyl, and mixtures thereof. Usually dihaloaromatic compounds are used, preferably p-dichlorobenzene. Incidentally, in order to increase the viscosity of the polymer due to the branched structure, a polyhaloaromatic compound having three or more halogen substituents in one molecule may be used in combination with a small amount of a dihaloaromatic compound.

The organic amide polar solvent used in the present invention is N.

N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-
It is selected from pyrrolidone, N-methyl-ε-caprolactam, hexamethylphosphoramide, etc., or a mixture thereof. Among these solvents, N-methyl-2-pyrrolidone (NMP) is particularly preferred.

The amount of the polyhaloaromatic compound used in the present invention is preferably 0.80 in molar ratio to the alkali metal hydrosulfide.
~1.30, more preferably 0.85~1.2
It is in the range of 0. The amount of the organic amide scratching solvent to be used is in a molar ratio of 1.5 to 30, preferably 2.0 to IO, relative to the alkali metal hydrosulfide.

In the first step of the polymerization reaction according to the method of the present invention, the amount of water in the system is 2.0 per mole of alkali metal hydrosulfide.
Must be less than mol. If the amount of water in the system exceeds 2.0 moles per mole of alkali metal hydrosulfide, this is not preferable because decomposition of the solvent during the polymerization reaction and inhibition of polymer chain elongation are likely to occur.

In the method of the present invention, the polymerization reaction temperature in the first step varies depending on the type of monomer used, but generally 1000
C to 255°C, for example, sodium hydrosulfide and p-
In case of dichlorobenzene combination, preferably 190°C
~230°C. The pressure should be within a range that substantially maintains the polymerization solvent and the polyhaloaromatic compound as the polymerization monomer in the liquid phase, and generally varies depending on the type of 7-mer used, but is generally between 200 kg/cs'' and 200 kg/cs.
kg/cm”, for example, sodium hydrosulfide and p
- in the case of dichlorobenzene combinations, preferably 0,5
kg/cab" to 100 kg/cm".

Reaction time varies depending on temperature and pressure, but is generally 0.
．． Within the range of 1 hour to 50 hours, for example, in the case of a combination of sodium hydrosulfide and p-dichlorobenzene,
The heating time is desirably 1 hour to 20 hours, and can be produced by heating preferably under an inert gas atmosphere.

There is no particular restriction on the order in which the components are mixed, and the mixing may be carried out by adding the above-mentioned components in portions in small amounts or all at once during the first step.

The amount of water used in the present invention is preferably within a range that dissolves in the solvent in the reaction system at the end of the first step, and separation will not be promoted even if it is used in an amount exceeding the solubility limit. The amount of water added is in the range of 5 to 40% by weight, preferably 5 to 20% by weight, based on the organic amide polar solvent.

The method of adding water is not particularly limited, but water may be added alone or after water is dispersed or dissolved in a polymerization solvent.

The above water addition time is after the first step, and while adding water, the temperature is raised to the temperature during the second step polymerization reaction.
Stay responsive.

The timing of adding water mentioned here may be before the temperature is raised to the temperature for the second step polymerization reaction, during the temperature rise, or after the temperature rise.

In the method of the present invention, the polymerization reaction temperature in the second step varies depending on the type of monomer used, but is generally 150°C.
The temperature is within the range of ~290°C and 15°C or more higher than that in the first step, for example, in the case of a combination of sodium hydrosulfide and p-dichlorobenzene, it is preferably 230°C ~ 27°C.
It is 0°C.

The pressure should be in a range that keeps the reactants substantially in the liquid phase and will vary depending on the monomers used;
Generally 0.5 kg/cs+" ~ 300 kg/cm
For example, in the case of a combination of sodium hydrosulfide and P-dichlorobenzene, it is preferably within the range of 2.5 k
g/cm2 to 100 kg/cm".The reaction time varies depending on the temperature and pressure, but is generally within the range of 0.5 to 20 hours, and is preferably produced by heating under an inert gas atmosphere. It can be done.

In the method of the present invention, the polymerization reaction is generally terminated by lowering the temperature to a temperature below the polymerization reaction conditions.

For example, it is preferable to flash the polymerization reaction product, in which the solvent substantially maintains a liquid phase, into a container under normal pressure or reduced pressure, and simultaneously lower the temperature. There is also a method of cooling the entire polymerization reaction vessel to complete the polymerization reaction.

In the method of the present invention, it is also preferable to add carbon dioxide during the polymerization reaction or at the end of the polymerization reaction, which not only prevents decomposition of the polymer and contributes to increasing the molecular weight of the resulting polymer, but also It is also effective in preventing decomposition of polymerization solvents.

Furthermore, it is also possible to carry out the dehydration and polymerization in the presence of low molecular weight arylene sulfide polymers in the process of the invention. A typical example of a low molecular weight polymer that can be used is polyphenylene sulfide with an intrinsic viscosity [η] of 0.2 or less, and the layer used is alkali metal hydrosulfide 1
0, O1 to 30 grams per mole, preferably 0.0
It is in the range of 5 to 20 grams.

The arylene sulfide polymer obtained by the method of the present invention can be produced by a conventional method, for example, after the completion of the polymerization reaction, the reaction mixture is filtered and then washed with water, or the reaction mixture is diluted with water, then filtered and washed with water, or a solvent is used. It can be separated from the reaction mixture by distilling and recovering it at normal pressure or reduced pressure, followed by washing with water and filtration.

Specific examples of arylene sulfide polymers produced by the method of the present invention typically include polyphenylene sulfide, including arylene sulfide polymers having other positions. Of course, copolymers of these polymers can also be mentioned. These arylene sulfide polymers can be used for injection molding, compression molding, extrusion molded products such as films, fibers, sheets, tubes, and blow molded products, and for sealing electronic components such as transistors, capacitors, and ICs. .

It is also suitable to incorporate fillers, pigments, flame retardants, stabilizers and other polymers into this polymer if necessary. For example, glass fiber or carbon fiber may be added to improve mechanical strength and heat resistance.

〔Example] The method of the present invention will be explained below according to examples.

215 Really Renesulfide Melt Flow Rate (
(hereinafter abbreviated as MFR) is 315.6°c (600°F)
, under a load of 5 kg with a preheating time of 5 minutes, the molten polymer was
(m, r: 2.095mta) is a numerical value that represents the speed at which the sample flows out through the following formula: L: Time required for the piston to move a specified distance (seconds) Weight of sample flowing out in wet seconds (g) Value calculated according to the formula: It is.

The viscosity stability (MFR2015) during melting is determined by preheating time 2.
The MFR (VFR20) at 0 minutes was measured, and the viscosity change from the MFR at a preheating time of 5 minutes was quantified, and the value was calculated according to 2: M I'I N .

The amount of gas generated was determined as shown in Figure 1 (using the measurement method using an ASTM type melt indexer,
0°F), the amount of gas generated in 8 minutes after 2 minutes of preheating under a load of 345 g, and is expressed by the formula: 1: Distance the load has moved upward (mm) W: Weight of the sample used for measurement ( g) This is the value calculated according to.

(Example 1) 335.3 g of sodium bisulfide 1.08 hydrate (NaSH
(4.271 mol in terms of conversion), then N M P
(Prepare 1500g, and add 327.9g of 48.0% sodium hydroxide aqueous solution (3.9g including NaOH)
35 mol) was charged, and the temperature was gradually raised to 200°C under N2 atmosphere for 2 hours while stirring at about 150 rpm, and a mixture of water and some NMP was distilled out, resulting in a final distillate of 245. 9g was obtained. When the water content in the main distillate was determined, it contained 243.5 g (theoretical amount of distilled water was 249.5 g).
7g), the amount of water remaining in the system at the end of the dehydration step was 0.08 mol to 1 mol of Na5H.

Next, 646.6 g of p-dichlorohenzene was added to this system.
(4,398 mol) and 348.4 g of NMP were added,
After polymerizing at 220°C for 4.5 hours, 79.0 g of water (H20/NMP = 8.7 wt% as a total amount of water) was added, the temperature was raised to 255°C, and polymerization was performed for 3 hours. The internal pressure at the end of the polymerization reaction was 13.2 kg/cab''.

The polymerization reaction was flash transferred via the bottom valve to a stainless steel container at normal pressure of 202, and the temperature of the reaction mixture slurry was lowered to 1.
The process was terminated by lowering the temperature to 00-120°C.

After diluting the reaction mixture slurry with a large amount of hot water according to a conventional method,
After washing with water and drying, 429.6 g (yield: 93.2%) of slightly brown polyphenylene sulfide was obtained.

The MFR of this polymer is 182 (g/10 min), M F
R2015 was 93%.

The amount of gas generated was 49.6 (μl/g).

[Examples 2 to 7 and Comparative Examples 1 to 2] They were produced in the same manner as in Example 1 except that the amount of NMP used and the amount of water added to sodium hydrosulfide were changed. The amounts used are listed in Table 1 along with their physical properties.

Apparently water was added at the beginning of the second step to carry out the polymerization. It can be seen that Examples 2 to 7 have higher molecular weights than Comparative Examples 1 to 2 in which no water is added, and also have higher viscosity stability during melting.

It is also clear that the amount of gas generated is also significantly lower in the example than in the comparative example.

[Example 8] A 4.5°C autoclave equipped with a stirrer and a bottom valve was heated to 48°C.
327.9 g of 0% sodium hydroxide aqueous solution (Na
0111A (calculated as 3.935 mol), then N
1500 g of M P was charged, and 335.3 g of sodium hydrosulfide 1.08 hydrate (4.271 mol in terms of NaS)I) was charged, and the mixture was heated for 160' under N2 atmosphere.
The temperature was gradually raised to C over 40 minutes while stirring at about 150 rpm+*, and a mixture of water and a small amount of NMP was distilled out to finally obtain 228.9 g of distillate. When the water content in the main distillate was quantified, it contained 226.6 g (theoretical amount of distilled water: 249.7 g), and the amount of water remaining in the system at the end of the dehydration step was 0.30 mol to 1 mol of Na5H.

Next, 646.6 g of p-dichlorobenzene was added to this system.
(4,398 mol) and 348.4 g of NMP were added,
After polymerizing at 200°C for 6 hours, 79.0 g of water (11□0/NMP = 8.7 wL% as a total amount of water) was added, and the temperature was raised to 230°C and polymerization was performed for 3 hours. The internal pressure at the end of the polymerization reaction was 9.2 kg/cm2.

The subsequent processing is the same as in the first embodiment.

The physical properties of the obtained polymers are shown in Table 2 for Example 9 and Comparative Example 3.
The results from 6 to 6 are also listed.

[Example 9 and Comparative Examples 3 to 6] Produced in the same manner as Example 8 except that the first step polymerization temperature and time and the second step polymerization temperature were changed. Those conditions are listed in Table 2 along with the physical properties.

The first step polymerization temperature and time, especially the temperature, are important in the main polymerization reaction, and as shown in Comparative Examples 3 and 4, the polymerization reaction does not proceed sufficiently at temperatures below the range of the present invention, and Comparative Example 5 As shown in Comparative Example 6, since side reactions occurred above the claimed range, the amount of gas generated increased, and a strange odor was felt compared to other Examples and Comparative Examples.

The unreacted rate of p-dichlorobenzene was analyzed by gas chromatography of the liquid fraction of the polymerization reaction product.

Comparative Example 7 A product was produced in the same manner as in Example 1, except that the timing of adding water was changed from after the first step to immediately after the second step.

The yield of the polymer obtained after the polymerization reaction was 430.6 g (yield 93.2%), V F R 1800 (g/10 min)
, MFR was 201598 (%), and the amount of gas generated was 340.2 (μil/g).

It can be seen that when water is added at a time other than after the first step, the molecular weight does not increase and the amount of gas generated increases.

[Example 10] 335.3 g of sodium bisulfide 1.08 hydrate (NaS
4.271 mol (calculated as H), then 48.0%
327.9 g of sodium hydroxide aqueous solution (llaO
3.935 mol (calculated as H), and further NMP15
00g was charged, and the temperature was gradually raised to 200°C under N2 atmosphere with stirring at about 15 Orpm over 2 hours, and a mixture of water and some NMP was distilled out, and finally distillate fraction 2
When the water content in the 0 distillate fraction obtained was 58.7g, it was determined that it contained 237.4g (theoretical distillate water amount: 249.7g).
, the amount of water remaining in the system at the end of the dehydration process is 0.16 mol vs. N
It was 1 mol of a5H.

Next, 646.6 g of p-dichlorobenzene was added to this system.
(4,398 mol) and 4 g of NMP 34B were added,
After polymerizing at 220°C for 4.5 hours, 79.0 g of water (HtO/NMP = 8.7 wt% as total water amount) was added, the temperature was raised to 255°C, and polymerization was performed for 3 hours. 0 Polymerization reaction completed. The internal pressure at that time was 9.2 kg/cm''.

The subsequent processing is the same as in the first embodiment.

The physical properties of the obtained polymer are listed in Table 3 together with the results of Example 11 and Comparative Examples 8-9.

[Example 11 and Comparative Examples 8 to 9] Produced in the same manner as in Example 1O except for changing the second step polymerization temperature and time. Those conditions are shown in Table 3 along with the physical properties.
Describe it in

Dotsu [Comparative Example 10] 549.6 g (l (4.271 mol in aslI conversion) of sodium sulfide 2.6 hydrate was used instead of sodium hydrosulfide 1.08 hydrate, and along with 48 % sodium hydroxide aqueous solution used from 327.9 g to 1.2
It was produced in the same manner as in Example 1 except for changing to g.

The polymer obtained after the polymerization reaction had a yield of 1t428.7g (yield 92.8%), an MFR of 260 (g/10 min), an MFR of
It was 2015133 (%). Also, the amount of gas generated is 2
It was 83.5 (μm/g).

[Example 12] NM in a 4.51 autoclave with a stirrer and a bottom valve.
P 1935 g was charged, and then 79.6 g of sodium hydrosulfide 1.08 hydrate solution (1935 g in terms of HaSH) was charged.
．． 014 mol) and further added 77.8 g of 48.0% aqueous sodium hydroxide solution (0.9 mol in terms of HaOH).
93 mol) was charged, and the temperature was gradually raised to 200°C under N2 atmosphere over 2 hours while stirring at about 150 rp++, and a mixture of water and some NMP was distilled out, resulting in a final distillate of 61. 1g was obtained. When the water content in the main distillate was determined, it contained 57.1 g (theoretical distilled water 159.3 g).
, the amount of water remaining in the system at the end of the dehydration process is 0.12 mol vs. Na
It was 1 mol of 5H.

This system was then charged with 291.1 g (1,014 moles) of 4,4'-dichlorodiphenylsulfone and NMP.
After adding 2.3 g of 5B and polymerizing at 180°C for 1 hour,
140.5 g of water (H,0/NMP = total amount of water)
6.4% by weight) was added, the temperature was raised to 200°C, and polymerization was carried out for 2 hours.

The internal pressure at the end of the polymerization reaction was 3.5 kg/cm'.

The subsequent processing is the same as in the first embodiment.

The physical properties of the obtained polymer are listed in Table 4 together with the results of Example 13 and Comparative Examples 11-12.

[Example 13 and Comparative Examples 11-12] Production was performed in the same manner as in Example 12, except that the types of various polyhaloaromatic compounds and the conditions listed in Table 4 were changed.

In Examples 12 to 13 in which water was added, the molecular weight was significantly higher than in Comparative Example 11-1'2 in which no water was added, and the amount of gas generated was also reduced.

[Example 14] 335.3 g of sodium bisulfide 1.08 hydrate (NaS
4.271 mol (calculated as H), then N M
1,500 g of P was charged, and 327.9 g of a 48.0% aqueous sodium hydroxide solution (3.0 g in terms of HaOH) was added.
935 mol) and heated to 200℃ under N2 atmosphere.
The temperature was gradually raised over time while stirring at about 15 Orpm, and a mixture of water and some NMP was distilled out to finally obtain 255.6 g of distillate. When the water content in the main distillate was determined, it contained 238.9 g (theoretical distillate water was 1249.9 g).
7g), the amount of water remaining in the system at the end of the dehydration step was 0.14 mol to 1 mol of Na5H.

Next, 646.6 g of P-dichlorobenzene was added to this system.
(4,398 mol) and 348.4 g of NMP were added,
After polymerizing at 220° C. for 4.5 hours, 79.0 g of water (11□0/NMP = 8.7% by weight as a total amount of water) was added, and the temperature was raised to 255° C. and polymerization was performed for 3 hours. The internal pressure at the end of the polymerization reaction was 13.1 kg/cn+2.

After that, stirring of the reaction mixture slurry was stopped, and 1/3 of the reaction mixture slurry was flash-transferred via the bottom valve to a stainless steel container at normal pressure of 50 to 80 μHg.
, NMP was removed by evaporation under conditions of 100 to 120°C.

This reaction mixture was diluted with a large amount of warm water according to a conventional method, washed with water, and dried to form a slightly brown polyphenylene sulfide 3.
I got 79.7 g.

The MFR of this polymer is 90 (g/10 min), MFR2
015 was 90%.

Further, the amount of gas generated was 49.6 (827 g).

[Example 15] 335.3 g of sodium bisulfide 1.08 hydrate (NaSt
4.271 mol in terms of liter), then N M
Prepare 1500 g of P, and then add 327.9 g (HaO) of 48.0% aqueous sodium hydroxide solution.
．． 935 mol) was charged, and the temperature was gradually raised to 200°C under N2 atmosphere over 2 hours while stirring at about 15° rpm, and a mixture of water and a small amount of NMP was distilled out, resulting in a final distillate of 257 mol). .3g was obtained. When the water content in the main distillate fraction was determined, it contained 242.7 g (theoretical distillate water amount: 249 g).
．． 7g), the amount of water remaining in the system at the end of the dehydration process is 0.09
mole to 1 mole of Na5H.

Next, 646.6 g of p-dichlorobenzene was added to this system.
(4,398 mol) and 348.4 g of NMP were added,
After polymerizing at 220°C for 4.5 hours, 79.0 g of water (HzO/NMP = 8.7 wt% as total water amount) was added, and the temperature was raised to 255°C and polymerization was performed for 3 hours. 0 Polymerization reaction completed. The internal pressure at that time was 13.2 kg/cs''.

After that, the stirring speed of the reaction mixture slurry was reduced to 1/10 of the speed of the polymerization reaction, and 1/1 of the reaction mixture slurry was stirred.
/3 quantity was flash transferred to a stainless steel container at normal pressure of 2ON via the bottom valve, and 50 to 80 anHg, 100 to 1
NMP was removed by evaporation at 20°C. The reaction mixture was diluted with a large amount of warm water in a conventional manner, washed with water, and dried to obtain 388.1 g of slightly brown polyphenylene sulfide.

The VFR of this polymer is 131 (g/10 min), M F
R2015 was 102%.

The amount of gas generated was 63.8 (μl/g).

[Example 16] 335.3 g of sodium bisulfide 1.08 hydrate (NaS
4.271 mol (calculated as H), then N M
1,500 g of P was charged, and 327.9 g of a 48.0% aqueous sodium hydroxide solution (3.0 g in terms of HaOH) was added.
935 mol) and heated to 200℃ under N2 atmosphere.
The temperature was gradually raised over time while stirring at about 15° rpm, and a mixture of water and a small amount of NMP was distilled out to finally obtain 260.5 g of distillate. When the water content in the main distillate was determined, it contained 241.2 g (theoretical distilled water amount: 249.2 g).
7g), the amount of water remaining in the system at the end of the dehydration step was 0.11 mol to 1 mol of Na5H.

Next, 646.6 g of p-dichlorobenzene was added to this system.
(4,398 mol) and 348.4 g of NMP were added,
After polymerizing at 220°C for 4.5 hours, 79.0 g of water (H!0/NMP = 8.7% by weight as the total amount of water) was added, the temperature was raised to 255°C, and polymerization was performed for 3 hours. The internal pressure at the end of the polymerization reaction was 13.4 kg/cm''.

Thereafter, stirring of the reaction mixture slurry was stopped, and 100 g of the reaction mixture slurry was flash transferred to a stainless steel container at normal pressure of 202 via the bottom valve, and the temperature was adjusted to about 80℃.
The temperature was lowered to ℃. Add 40 ml of warm water to this reaction mixture slurry.
After adding 0g and heating using a filter press,
The furnace residue was washed with water, washed and dried to obtain 378.3 g of slightly brown polyphenylene sulfide.

VFR of this polymer is 9B (g/10 min), MFR2
015 was 101%.

Further, the amount of gas generated was 56.7 (μ!/g).

〔Effect of the invention〕

The high molecular weight polymer produced by the method of the present invention has significantly lower volatile components and gas generation than conventional production methods, and also has significantly improved viscosity stability when melted. This is considered to be because the low molecular weight components in the polymer are reduced. Further, along with this, foaming during melt molding, mold corrosion, thermal stability of the product, mechanical properties, etc. are significantly improved.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a melt indexer when measuring the amount of gas generated.

Claims (5)

[Claims] (1) In the production of polyarylene sulfide, (A
) At least one alkali metal hydrosulfide, at least one alkali metal hydroxide, and at least one polyhaloaromatic compound in the presence of at least one organic amide polar solvent at 1000 C to 225 C, 0.1 to 5
First step of reacting for 0 hours, (B) Water is added so that 5 to 40 parts by weight of water including hydration water is present per 100 parts by weight of organic amide polar solvent, and at 150 ° C. to 290 ° C. of polyarylene sulfide, which is carried out in two steps: a second step in which the temperature is raised to a temperature 15 degrees Celsius or more higher than in the first step and the reaction is maintained for 0.5 to 20 hours. Production method. (2) The production method according to claim 1, wherein the reaction mixture obtained is taken out into a takeout container at normal pressure or reduced pressure under heating at a high temperature in which the obtained reaction mixture is substantially in a liquid phase state. (3) The manufacturing method according to claim 2, wherein the solid material produced in the take-out container under normal pressure or reduced pressure is taken out while stirring to such an extent that it does not form into lumps. (4) The manufacturing method according to claim 2, wherein a part of the lower layer is taken out from the reaction mixture which is substantially separated into two layers. (5) Claim 2: A portion of the reaction mixture that has been substantially separated into two layers is taken out from the lower layer, and the remainder is used for the next reaction.
Manufacturing method described in section.