JPH09194592A - Production of polyarylene sulfide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a polyarylene sulfide resin composition useful for an electronic part, a camera, etc., capable of obtaining a dark colored molding and a good black colored one with an additional small amount of carbon black by carrying out a specified treatment. SOLUTION: This polyarylene sulfide resin composition is produced by treating a polyarylene sulfide(PAS) with an aqueous solution containing the corresponding amount of an iron compound such as ferric oxide to 0.005-10 pts.wt iron atom based on 100 pts.wt. PAS. In that case, for example, the powdery PAS is preferably formed into 5-60wt.% slurry (based on the PAS concentration) with the aqueous solution containing the iron compound and treated for contacting each other at a temperature between a normal temperature and 160 deg.C for a period between 5 minutes and 2 hours under a pressure between an atmospheric pressure and about 10kg/cm<2> by stirring.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyarylene sulfide resin composition.

[0002]

2. Description of the Related Art Polyphenylene sulfide (hereinafter referred to as P
Polyarylene sulfide (sometimes abbreviated as PS) (hereinafter sometimes abbreviated as PAS) is a thermoplastic resin having high heat resistance and chemical resistance, and is used as an electric / electronic device component. It is used for automobile equipment parts, chemical equipment parts, etc.

Most of the colors of such PAS molded products are the same as the material color or colored black. The hue of PAS itself varies depending on the manufacturing method, the post-treatment method, and the like. In particular, the hue of so-called cross-linked PAS, which occupies most of the market at present, is 50 or less (dark color) in hot press L value, but the value is different for each product and is wide range. . Therefore, when assembling different parts made of different grades of PAS to make a product, a hue shift between the parts may be a problem. In particular, molded products that require a beautiful appearance, such as electronic parts, home appliance parts,
Alternatively, it has been a problem when used for precision mechanical parts such as cameras and watches. Further, in order to obtain a black molded product, carbon black is added to PAS. However, when components are used in combination, it is necessary to adjust the addition amount of carbon black in order to reduce the difference in hue between the components, which is a drawback that the work becomes complicated. Further, there is also a drawback that PAS physical properties such as mechanical strength are deteriorated as the amount of carbon black added increases.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a PAS resin composition which is capable of obtaining a dark-colored molded article having a good black color by adding a small amount of carbon black.

[0005]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above problems. As a result, they have found that the above problems can be solved by using the following predetermined manufacturing method, and have completed the present invention.

That is, according to the present invention, (1) polyarylene sulfide is treated with an aqueous solution containing an iron compound in an amount corresponding to 0.005 to 10 parts by weight of iron atom based on 100 parts by weight of polyarylene sulfide. And a method for producing a polyarylene sulfide resin composition.

As a preferred embodiment of the present invention, (2) the amount of the iron compound is an amount corresponding to 0.01 to 5 parts by weight of iron atom based on 100 parts by weight of polyarylene sulfide. A method can be mentioned.

Using the manufacturing method of the present invention, it is possible to manufacture a PAS having a desired dark hue. Therefore, the hues of different grades of PAS can be matched. That is, when parts made of different grades of PAS are assembled to produce a product, there is little hue shift between the parts, and a well-balanced hue can be obtained. Further, when the obtained PAS is blackened, a sufficiently satisfactory black molded product can be produced by adding a small amount of carbon black. Therefore, the mechanical strength is not lowered by the addition of a relatively large amount of carbon black, which has been a problem in the past. Further, as described above, since the color balance of the raw material color is good, it is not necessary to adjust the addition amount of carbon black for each component when blackening. Therefore, the manufacturing process of the black product can be simplified.

Japanese Unexamined Patent Publication No. 64-11136 discloses a PA
A method of treating S in a fluidized bed of iron and / or an iron-based compound to produce a highly melt-resistant PAS resin is described. The method uses PAS and / or an iron-based compound as a catalyst.
Is infusibilized, that is, thermally oxidized and crosslinked. In contrast, the present invention treats PAS with an iron compound in water to blacken PAS.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the method for producing a PAS resin composition of the present invention, the upper limit of the amount of iron compound used is 10 parts by weight, preferably 5 parts by weight, and particularly preferably 3 parts by weight, per 100 parts by weight of PAS. It is an amount corresponding to 1 part by weight of iron atoms, and the lower limit is an amount corresponding to 0.005 parts by weight, preferably 0.01 parts by weight, and particularly preferably 0.03 parts by weight. Even if the upper limit is exceeded, the effect of the invention does not increase remarkably and, on the other hand, the electrical properties such as the moldability of the obtained PAS resin composition and the insulating property of the molded product are adversely affected. If it is less than the above lower limit, the iron content in the PAS resin composition becomes low, and the hue of the molded product cannot be made sufficiently dark.

The method of treating PAS with an aqueous solution containing an iron compound is preferably as follows.

First, the solvent and by-products are separated from the PAS slurry produced in the PAS production step, preferably by flash evaporation or filtration to obtain a dry powder or cake PAS. Next, the PAS is preferably made into a water slurry in advance, and then the iron compound is mixed as it is or as an aqueous solution with the water slurry. The treatment is preferably
It can be performed together with the removal of the by-product salt generated in the PAS manufacturing process. For example, the removal of the by-product salt is usually carried out by repeating the operation of making PAS obtained by separating as described above into a slurry with water and filtering it several times. P at any stage of this repeated operation
It can be carried out by mixing an iron compound in a water slurry of AS. Further, the effect of the present invention can be sufficiently achieved even if the iron compound is mixed with the water slurry at any stage. The concentration of PAS in the slurry is preferably 2 to 60% by weight for the convenience of the treatment or the handling after the treatment.
And particularly preferably 5 to 30% by weight. PAS
If the concentration is less than the above lower limit, the treatment time becomes long, and if it exceeds the above upper limit, the fluidity of the slurry is reduced, which is not preferable in the process, and the effect of removing the by-product salt produced in the PAS production step is also reduced. The processing temperature is preferably room temperature to 2
00 ° C., particularly preferably room temperature to 160 ° C. If the upper limit is exceeded, equipment with high withstand voltage is required, and equipment costs increase. The treatment time is preferably 5 minutes to 2 hours, particularly preferably 10 minutes to 1 hour, though it varies depending on the treatment temperature and the nature of the PAS to be treated. Further, the pressure is only required to be able to maintain the water in the mixture as a liquid phase, and is preferably atmospheric pressure to about 10 kg / cm ² . Exceeding the above-mentioned pressure is not preferable because the facility cost becomes high as above.

The above treatment can be carried out in either a batch system or a continuous system. A convenient way to carry out the treatment is to contact the water slurry of eg PAS with the iron compound in a closed tank with a stirrer. The contacting can be done in a single or multiple vessels. Separation of PAS from the slurry after contact and drying thereof can be carried out by using a generally known method.

When the by-product salt produced in the PAS manufacturing process is removed by a washing method in which water is poured into the filter cake, the treatment with an aqueous solution containing an iron compound is
The washing step can be carried out by pouring an aqueous solution containing an iron compound into the filter cake.

The PAS resin composition thus obtained has P
The iron compound (calculated as iron atom) is preferably 0.0005 to 3 parts by weight, particularly preferably 0.001 to 1 part by weight, and further preferably 0.005 parts by weight relative to 100 parts by weight of AS.
~ 0.5 parts by weight. Even if the amount of iron compound is more than the above upper limit, the effect of the present invention does not increase remarkably and, on the other hand, it adversely affects the electrical properties such as moldability and insulating property of the molded product. When the iron compound content is less than the above lower limit, the PAS resin composition does not become dark.

Examples of the iron compound used in the present invention include ferric oxide, ferric tetroxide, ferrous chloride, ferric chloride, ferrous hydroxide, ferric hydroxide, and iron suboxide. Iron sulfate,
Examples thereof include iron sulfide, iron nitrate and iron phosphate. Preferably, iron oxide and / or iron chloride is used, and from the viewpoint of effect and economy, ferric tetroxide or ferric chloride is particularly preferably used.

PAS used in the method of the present invention is a known polymer having an arylene sulfide repeating unit, and particularly preferably PPS. The method for producing the PAS is not particularly limited. For example, Japanese Patent Publication No. 45-336
Method for producing PAS by reacting an alkali metal sulfide with a dihaloaromatic compound in an organic amide-based solvent described in JP-B-8, method using an alkali metal carboxylate described in JP-B-52-12240 U.S. Pat. No. 403
No. 8263, a method using a polymerization aid such as lithium halide, a method using a crosslinking agent such as a polyhaloaromatic compound described in JP-B No. 54-8719,
It can be produced by a method using a multi-step reaction in the presence of different water described in JP-B-63-33775.

[0018] Preferably, in the method described in JP-A-5-222196 for producing PAS by reacting an alkali metal sulfide with a dihaloaromatic compound in an organic amide solvent, a reaction vessel is used during the reaction. It is possible to use a method in which a part of the gas phase in the reaction vessel is condensed by cooling the gas phase part of the above and the solution is refluxed to the liquid phase. By using this method, P having a relatively high melt viscosity V ₆ can be obtained.
AS can be manufactured, and therefore, PAS having high mechanical strength such as tensile strength and impact strength can be obtained, which is preferable.

In this method, the refluxed liquid has a higher water content than the liquid phase bulk because of the difference in vapor pressure between water and the amide solvent. The reflux liquid having a high water content forms a layer having a high water content at the upper portion of the reaction solution. As a result, a large amount of residual alkali metal sulfide (eg, Na ₂ S), alkali metal halide (eg, NaCl), oligomers, and the like are contained in the layer. In the conventional method, 2
At a high temperature of 30 ° C. or more, when the produced PAS is uniformly mixed with raw materials such as Na ₂ S and by-products, not only can a high molecular weight PAS not be obtained, but also a solution of the produced PAS can be obtained. Polymerization also occurs, and by-products of thiophenol are observed. However, in the present invention, the above disadvantageous phenomenon can be avoided by actively cooling the gas phase portion of the reaction vessel and returning a large amount of the water-rich reflux liquid to the upper part of the liquid phase so as to inhibit the reaction. It can be considered that such factors can be effectively eliminated and a high molecular weight PAS can be obtained. However, the present invention is not limited only by the effect of the above phenomenon, and a high molecular weight PAS can be obtained by various effects caused by cooling the gas phase portion.

In this method, it is not necessary to add water during the reaction. However, this does not preclude the addition of water at all. However, with the addition of water, some of the advantages of this method are lost. Therefore,
Preferably, the total amount of water in the polymerization reaction system is constant during 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 through an internal coil installed at an upper part in a reaction can, a method of flowing a cooling medium through an external coil or a jacket wrapped around the upper part of the reaction can, and using a reflux condenser installed at the upper part of the reaction can A method such as spraying water or blowing a gas (air, nitrogen, etc.) on the upper portion of the outside of the reaction vessel is conceivable, but any method can be used as long as it has the effect of increasing the amount of reflux in the vessel as a result. May be used. If the outside air temperature is relatively low (for example, normal temperature), appropriate cooling can be performed by removing a heat insulating material conventionally provided on the upper part of the reaction vessel. In the case of external cooling, water condensed on the reactor wall
The amide-based solvent mixture enters the liquid phase along the reaction vessel wall. 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 down the cooling device surface or the reactor wall and 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 preferred 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 for 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 low, 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 phase,
Dihalo aromatic compound residual rate in the polymerization reaction system is 1 mol% to 40
It is preferable to carry out the reaction at a time point when the molar% is within the range of 3,000 to 20,000. More preferably, the residual ratio of the dihalo aromatic compound in the polymerization reaction system is in the range of 2 mol% to 15 mol%, and the molecular weight is in the range of 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 hard 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
When the temperature is higher than 270 ° C., side reactions such as depolymerization are liable to occur, making it difficult to stably obtain a high molecular weight product.

As an actual operation, first, dehydration or water addition is carried out in an inert gas atmosphere, if necessary, so that the amount of water in the alkali metal sulfide in the amide solvent becomes a predetermined amount. The water content is preferably the 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 moles, 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.

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. The degree of the cooling effect is usually the most suitable index of the pressure in the reactor. 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, when the pressure in the reaction vessel is reduced as compared with the case where the reaction vessel is not cooled under the same reaction conditions, the amount of the reflux liquid increases, which means that the temperature at the gas-liquid interface of the reaction solution decreases. It is considered that the relative degree of decrease indicates the degree of separation between a layer having a high water content and a layer having no water content. Therefore, it is preferable to perform cooling to such an extent that the internal pressure of the reaction vessel is 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.

The organic amide solvent used here is PA
Known for S-polymerization, such as N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylcaprolactam, etc., and mixtures thereof can be used, with N-methylpyrrolidone being preferred . They all have a lower vapor pressure than water. Alkali metal sulfides are also known, for example lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide,
Cesium sulfide and mixtures thereof. These hydrates and aqueous solutions may be used. Hydrosulfides and hydrates corresponding to these can be used after being neutralized with the corresponding hydroxides. Inexpensive sodium sulfide is preferred.

The dihalo aromatic compound is, for example, Japanese Patent Publication No.
It can be selected from those described in JP-A-5-3368, but is preferably p-dichlorobenzene. Further, a copolymer can be obtained by using one or more kinds of para-, meta- or ortho-dihalides of diphenyl ether, diphenyl sulfone or biphenyl in a small amount (20 mol% or less). For example, m-dichlorobenzene, o-dichlorobenzene,
p, p'-dichlorodiphenyl ether, m, p'-dichlorodiphenyl ether, m, m'-dichlorodiphenyl ether, p, p'-dichlorodiphenylsulfone, m, p'-dichlorodiphenylsulfone, m, m '
-Dichlorodiphenyl sulfone, p, p'-dichlorobiphenyl, m, p'-dichlorobiphenyl, m, m'-
Dichlorobiphenyl.

In order to increase the molecular weight of PAS,
It is also possible to use the polyhaloaromatic compound in a concentration of preferably 5 mol% or less based on the dihaloaromatic compound.
The polyhaloaromatic compound is a compound having three or more halogen substituents in one molecule, such as 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene,
1,3,5-trichlorobenzene, 1,3-dichloro-
5-bromobenzene, 2,4,6-trichlorotoluene, 1,2,3,5-tetrabromobenzene, hexachlorobenzene, 1,3,5-trichloro-2,4,6-
Trimethylbenzene, 2,2 ', 4,4'-tetrachlorobiphenyl, 2,2', 6,6'-tetrabromo-
3,3 ', 5,5'-tetramethylbiphenyl, 1,
2,3,4-tetrachloronaphthalene, 1,2,4-tribromo-6-methylnaphthalene and the like and mixtures thereof are mentioned, 1,2,4-trichlorobenzene, 1,
3,5-trichlorobenzene is preferred.

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

The PAS thus obtained can be separated from by-products by post-treatment methods known to those skilled in the art.

Further, in the present invention, PAS obtained by the various methods described above may be further subjected to a thermal oxidative crosslinking treatment.

The PAS resin composition obtained by the method of the present invention may contain an inorganic filler as an optional component. The inorganic filler is not particularly limited, but powdery / scaly fillers, fibrous fillers and the like can be used. Examples of the powdery / scaly filler include silica, alumina, talc, mica, kaolin, clay,
Examples thereof include silica alumina, titanium oxide, calcium carbonate, calcium silicate, calcium phosphate, calcium sulfate, magnesium oxide, magnesium phosphate, silicon nitride, glass, hydrotalcite, zirconium oxide, glass beads and carbon black. Further, as the fibrous filler, for example, glass fiber, asbestos fiber,
Examples thereof include carbon fiber, silica fiber, silica / alumina fiber, potassium titanate fiber, polyaramid fiber and the like. Also,
In addition to this, a filler such as ZnO tetrapot, metal salt (eg, zinc chloride, lead sulfate, etc.), oxide (eg, iron oxide, molybdenum dioxide, etc.), metal (eg, aluminum, stainless steel, etc.) can also be used. These are 1
They may be used alone or in combination of two or more. Further, the surface of the inorganic filler may be treated with a silane coupling agent or a titanate coupling agent. The inorganic filler is used in an amount of 400 parts by weight or less, preferably 300 parts by weight or less, based on 100 parts by weight of PAS. If the amount of the inorganic filler exceeds the above value, the change in viscosity becomes large and molding may not be possible. Further, in order to increase the mechanical strength, it is preferable to add 1 part by weight or more.

Further, known additives and fillers such as antioxidants, ultraviolet absorbers, release agents, heat stabilizers, lubricants and the like can be added, if necessary.

The production of a molded article is carried out, for example, by previously mixing the above components with a mixer such as a Henschel mixer, melt-kneading them with a conventional apparatus such as an extruder, extruding, pelletizing, and then injection molding, It can be carried out by extrusion molding or the like.

The PAS obtained by the method of the present invention
The resin composition is preferably suitable for the addition of carbon black to produce black shaped articles. The total amount of carbon black added is 10 for PAS and iron compounds.
With respect to 0 part by weight, the upper limit is preferably 5 parts by weight, particularly preferably 1 part by weight, and the lower limit is preferably 0.01 part by weight, particularly preferably 0.05 part by weight. If the upper limit is exceeded, the mechanical strength such as impact strength and tensile strength of the molded product will decrease, and if it is less than the lower limit, a satisfactory black molded product cannot be obtained. In the PAS resin composition of the present invention, a sufficiently satisfactory black molded product can be obtained by adding a small amount of carbon black. Therefore, the mechanical strength such as impact strength and tensile strength of the molded product, which has been conventionally caused by the large amount of addition, is not reduced. Furthermore, since the hues of the combined PASs can be matched in advance in the material color, it is not necessary to adjust the addition amount of carbon black in accordance with the hue of the combined PASs when blackening. Therefore, the manufacturing process of the black product can be significantly simplified.

The PAS resin composition obtained by the method of the present invention can be used as a material for automobile equipment parts, electric / electronic equipment parts, chemical equipment parts, and other machine parts. In particular, it is useful for appearances that require beautiful color tones of the molded articles to be combined, such as electronic parts, home electric appliances, or precision machine parts such as cameras and watches.

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

[0037]

EXAMPLES In the examples, the iron content in the PPS composition was measured using an atomic absorption spectrophotometer AA660 manufactured by Shimadzu Corporation. Here, the iron content of each Example and Comparative Example is a value calculated by comparing the PPS of Comparative Example 1 containing no iron compound as a standard sample with the standard sample. The pretreatment was carried out by wet decomposition with H ₂ SO ₄ —HClO ₄ system.

The whiteness (hot press L value) was 1.5 at 320 ° C. after preheating the PPS composition at 320 ° C. for 1.5 minutes.
For 30 min / cm ² at 130 ° C for 1.5 min
A disk-shaped plate was prepared by pressure molding with a hot press at a pressure of 1 and was measured using a color difference meter (Color Ace, manufactured by Tokyo Denshoku Co., Ltd.).

The flow tester used for measuring the melt viscosity V ₆ is a flow tester CFT-500C manufactured by Shimadzu Corporation.
It is.

[0040]

Example 1 Flake sodium sulfide (60.5 wt% Na ₂ S) 19.31 was placed in a 150 liter autoclave.
7 kg and N-methyl-2-pyrrolidone (hereinafter NMP
45.0 kg was charged. While stirring under a nitrogen stream, the liquid temperature was raised to 204 ° C. and water was adjusted to 4.60.
0 kg was distilled off (the amount of residual water was 1.08 mol per mol of sodium sulfide). Then, the autoclave was sealed and cooled to 180 ° C., and 22.463 kg of p-dichlorobenzene (hereinafter sometimes abbreviated as p-DCB) and 18.0 kg of NMP were charged. The temperature was started by pressurizing to 1 kg / cm ² G with nitrogen gas at a liquid temperature of 150 ° C. When the liquid temperature reached 255 ° C, the temperature was stopped and the mixture was stirred for 3 hours as it was.

The obtained slurry is filtered by a conventional method,
Washing with warm water was repeated. Next, the obtained PPS and water were mixed to form a slurry (PPS concentration was 11.0% by weight), and ferric chloride was added so that the iron atoms were 0.05 parts by weight with respect to 100 parts by weight of PPS. Aqueous solution was added. This is stirred at room temperature for 30 minutes, filtered, washed with warm water, and kept at 120 ° C.
PPS in powder form after drying in a hot air circulation dryer for about 5 hours
A composition was obtained.

[0042]

Examples 2 to 5 Each PPS composition was prepared in the same manner as in Example 1 except that the iron compounds and the amounts shown in Table 1 were used.

[0043]

[Example 6] The same procedure as in Example 1 was repeated, except that an aqueous ferric chloride solution was added to an aqueous slurry of PPS and then the mixture was stirred in an autoclave at 150 ° C for 2 hours.
A PPS composition was produced.

[0044]

Examples 7 and 8 Each PPS composition was produced in the same manner as in Example 6, except that the amounts of ferric chloride shown in Table 1 were used.

[0045]

[Comparative Example 1] Except that the ferric chloride aqueous solution was not added,
The same procedure as in Example 1 was carried out to produce PPS.

PP obtained in each of the above Examples and Comparative Examples
Iron content of S composition, hot press L value and melt viscosity V
₆ is shown in Table 1.

[0047]

[Table 1] In Examples 1 to 4, ferric chloride was used as the iron compound, the amount of iron used was varied within the range of the method of the present invention, and the treatment was performed at room temperature. L of the obtained PPS composition
The value was low and a dark PPS composition was obtained. Increasing the amount of iron used increases the iron content in the PPS composition,
It was found that the L value of the hot press can be lowered. In Example 5, ferrous chloride was used as the iron compound and treated at room temperature. The L value was low and a dark PPS composition was obtained. In Examples 6 to 8, the treatment temperature and time were 150 ° C. and 2 at the same iron usage amounts as in Examples 1, 3 and 4, respectively.
It is time. Similar to the above, the L value of the obtained PPS composition was low, and a dark-colored PPS composition was obtained. It was found that when the amount of iron used was increased, the iron content in the PPS composition was increased, and the hot press L value could be lowered. Further, when the treatment temperature was increased, the hot press L value tended to be lower.

On the other hand, Comparative Example 1 was not treated with the iron compound. The hot press L value was high, and when the value was over 50, it was bright and dark-colored PPS was not obtained.

[0049]

Example 9 and Comparative Example 2 For 100 parts by weight of each of the PPS composition obtained in Example 1 and the PPS obtained in Comparative Example 1, glass fiber (CS 3PE945S, trademark, manufactured by Nitto Boseki Co., Ltd.) 66 0.7 parts by weight were blended and pre-mixed for 5 minutes using a Henschel mixer to homogenize, then 2
Using a 0 mmφ twin-screw counter-rotating extruder, temperature 300
Pellets were prepared by melt-kneading at ℃ and rotation speed of 400 rpm. The obtained pellets were supplied to an injection molding machine and injection-molded at a cylinder temperature of 320 ° C. and a mold temperature of 130 ° C. to prepare a box having a length of 4 cm × a width of 8 cm × a height of 3 cm × a thickness of 0.3 cm.

On the other hand, the PPS obtained in Comparative Example 1 was added to 230
It heat-processed for 16 hours in the oven set to ℃. The melt viscosity V ₆ of the obtained crosslinked PPS was 2030 poise,
The hot press L value was 34.0. Using the PPS, in the same manner as above, length 4 cm × width 8 cm × thickness 0.3.
A cm lid was made for the box.

The box made of the PPS composition of Example 1 (L value was 34.5) and the lid were in a well-balanced combination because the hues were almost the same.

On the other hand, the box made of PPS of Comparative Example 1 (L value is 51.0) is remarkably different in hue from the lid, and the box is bright and the lid is unbalanced. It was a good combination and looked bad.

[0053]

Example 10 and Comparative Example 3 A box and a lid were prepared in the same manner as in Example 9 and Comparative Example 2 except that carbon black (HS-D912678, trademark, manufactured by Dainichiseika Kogyo Co., Ltd.) was blended as a colorant. Was molded. At this time, the blending amount of carbon black was 0.15 parts by weight with respect to 100 parts by weight of the PPS composition obtained in Example 1,
The PPS obtained in Comparative Example 1 was 0.45 parts by weight based on 100 parts by weight of the PPS, and the crosslinked PPS obtained by heat treatment was 0.1% by weight based on 100 parts by weight of the PPS.
It was 15 parts by weight.

Table 2 shows the impact strength and tensile strength of each box and lid.
It was as follows.

[0055]

Table 2 Example 10 Comparative Example 3 Box lid Box lid Box lid Izod impact strength 31.0 34.0 22.0 34.0 (kgf · cm / cm) Tensile strength (kgf / cm ² ) 1700 1750 1550 1750 As described above, the impact strength and tensile strength of the box of Example 10 were high, and the color balance between the box and the lid was good and beautiful. On the other hand, the impact strength and tensile strength of the box of Comparative Example 3 were significantly lower than those of Example 10 because a large amount of carbon black was added. Further, in the box of Comparative Example 3, a sufficient black color could not be obtained despite the addition of a large amount of carbon black, and the color balance between the box and the lid was unbalanced.

Here, the impact strength and the tensile strength are 12.7 × 80 × 3 from each box and lid molded as described above.
Cut out a mm-shaped tanzaku-shaped test piece and
It is measured according to TMD256 and ASTM D638.

[0057]

Industrial Applicability The present invention provides a method for producing a PAS resin composition which is capable of obtaining a dark-colored molded product having a good black color by adding a small amount of carbon black.

Claims (2)

[Claims] 1. A polyarylene sulfide is added in an amount of 0.005-1 based on 100 parts by weight of the polyarylene sulfide.
A method for producing a polyarylene sulfide resin composition, which comprises treating with an aqueous solution containing an iron compound in an amount corresponding to 0 part by weight of an iron atom. 2. The method according to claim 1, wherein the amount of the iron compound is an amount corresponding to 0.01 to 5 parts by weight of iron atom based on 100 parts by weight of polyarylene sulfide.