JP6428103B2 - Polyarylene sulfide resin composition - Google Patents

Description

  The present invention relates to a polyarylene sulfide resin composition that is improved in white color tone as an exterior part by suppressing eyes and eyes in the production of the polyarylene sulfide resin composition, and also excellent in impact resistance and molding fluidity. More particularly, the present invention relates to a polyarylene sulfide resin composition that is particularly useful for electronic / electrical parts such as a casing of a portable terminal device such as a mobile personal computer, a tablet, and a mobile phone, or for electric parts such as an automobile electrical part. It is.

  Polyarylene sulfides (hereinafter sometimes abbreviated as PAS) represented by poly (p-phenylene sulfide) (hereinafter also abbreviated as PPS) have excellent mechanical properties, thermal properties, It has electrical properties and chemical resistance, and is widely used for many electrical / electronic equipment members, automotive equipment members, and other OA equipment members.

  PAS can greatly improve mechanical strength, heat resistance, rigidity, and the like by blending fibrous inorganic fillers such as glass fibers and granular inorganic fillers such as calcium carbonate and talc. However, PAS is inferior in white tones compared to other engineering plastics, and its use as an exterior component in electronic and electrical component applications such as the case of mobile terminal devices such as mobile personal computers, tablets and mobile phones is restricted. There is a case.

  As a technique for improving the white color tone of PAS, it is known to add a white pigment or the like to PAS. For example, a resin composition comprising polyphenylene sulfide, a glass filler and anatase-type titanium dioxide as a pigment (see, for example, Patent Document 1), a polyarylene sulfide, a fibrous filler, and a resin composition comprising zinc sulfide as a pigment (for example, Patent Document 2), polyarylene sulfide, a polyarylene sulfide resin composition containing silica (for example, see Patent Document 3), and the like have been proposed.

  However, when producing a polyarylene sulfide resin composition containing these inorganic fillers, when the molten resin flows out from the tip of the extruder die, due to poor dispersion of the inorganic filler or resin degradation, die lip, etc. In some cases, a deteriorated resin called an eye or an aggregate of inorganic filler adheres and accumulates. In the eyes and eyes thus formed, deterioration and discoloration are caused by the heat of the die, and the appearance of the polyarylene sulfide resin composition flowing out from the die is adhered to the surface of the product and the appearance of the product is deteriorated. It will be easy.

  And as a technique for suppressing the eyes of PAS, the thermoplastic resin composition is characterized in that the resin temperature after supplying the filler is maintained at (Tm-40) ° C. or higher (Tm is the melting point of the thermoplastic resin). Manufacturing method (for example, see Patent Document 4), a nozzle die mounting hole provided in a metal die body made of ceramic mainly composed of silicon nitride (for example, see Patent Document 5). Etc. have been proposed.

  In addition, a flame retardant resin composition (see, for example, Patent Document 6) characterized in that it may contain a thermoplastic resin, a metal hydrate, and a metal salt of 12-hydroxystearic acid as an inhibitor to the eyes. Has been.

Japanese Patent Laid-Open No. 5-70624 (see, for example, claims) Japanese Patent Laid-Open No. 5-39417 (for example, refer to the claims) Japanese Patent Laid-Open No. 9-71723 (see, for example, claims) Japanese Patent Laid-Open No. 6-238655 (for example, refer to the claims) Japanese Patent Laid-Open No. 5-77305 (for example, refer to the claims) Japanese Patent Laying-Open No. 2008-7730 (for example, refer to the claims)

  However, in the resin compositions proposed in Patent Documents 1 to 3, although a resin composition excellent in white color tone has been proposed, further white color tone, impact resistance and improvement in molding fluidity are desired, In general, no consideration has been given to resin degradation. In addition, in the proposals of Patent Documents 4 and 5, no consideration is given to modification as a resin composition and use of an inhibitor. Further, regarding the resin composition proposed in Patent Document 6, PAS is of course not described at all for the polyarylene sulfide resin composition excellent in white color tone, impact resistance and molding fluidity.

  Therefore, the present invention aims to improve the white color tone as an exterior part by suppressing eyes and eyes in the production of the polyarylene sulfide resin composition, and to improve the impact resistance and molding fluidity of the polyarylene sulfide resin composition. It is an object of the present invention to provide a polyarylene sulfide resin composition that is particularly useful for use in electronic and electrical parts such as housings of mobile terminal devices such as mobile personal computers, tablets, and mobile phones.

  As a result of intensive studies to solve the above problems, the present inventors are composed of a specific polyarylene sulfide resin, a glass fiber, a specific white pigment, and a 12-hydroxystearic acid metal salt, and have a specific blending ratio. The present inventors have found that the resin composition can be a polyarylene sulfide resin composition excellent in white color tone, impact resistance and molding fluidity, and have completed the present invention.

That is, according to the present invention, an elevated flow having a lightness (L value) of 70 or more formed by compression molding at a melting temperature of 310 ° C. and a pressure of 100 kgf / cm ² and equipped with a die having a diameter of 1 mm and a length of 2 mm. A group consisting of titanium oxide, zinc oxide and zinc sulfide with respect to 100 parts by weight of polyarylene sulfide resin (A) having a melt viscosity of 50 to 1000 poise measured with a tester at a measurement temperature of 315 ° C. and a load of 10 kg. 10 to 50 parts by weight of at least one or more selected white pigment (B), 20 to 40 parts by weight of glass fiber (C) and 0.05 to 2 parts by weight of 12-hydroxystearic acid metal salt (D) It is related with the polyarylene sulfide resin composition characterized by these.

  The present invention is described in detail below.

In the polyarylene sulfide resin composition of the present invention, the lightness (L value) of a molded product compression-molded at a melting temperature of 310 ° C. and an applied pressure of 100 kgf / cm ² is 70 or more, and a die having a diameter of 1 mm and a length of 2 mm is mounted. The polyarylene sulfide resin (A) having a melt viscosity of 50 to 1000 poises measured under the conditions of a measurement temperature of 315 ° C. and a load of 10 kg with a Koka type flow tester, titanium oxide, zinc oxide and 10 to 50 parts by weight of at least one white pigment (B) selected from the group consisting of zinc sulfide, 20 to 40 parts by weight of glass fiber (C) and 0.05 to 12-hydroxystearic acid metal salt (D) By including 2 parts by weight, it is possible to suppress eyes and corners during production and to have excellent impact resistance and molding fluidity.

As the polyarylene sulfide resin (A) constituting the polyarylene sulfide resin composition of the present invention, the lightness (L value) of a molded article compression-molded at a melting temperature of 310 ° C. and a pressure of 100 kgf / cm ² is 70 or more. A polyarylene sulfide resin having a melt viscosity of 50 to 1000 poise measured under conditions of a measurement temperature of 315 ° C. and a load of 10 kg with a Koka flow tester equipped with a die having a diameter of 1 mm and a length of 2 mm, The polyarylene sulfide resin may belong to a category generally called polyarylene sulfide resin. Examples of the polyarylene sulfide resin include p-phenylene sulfide units, m-phenylene sulfide units, o-phenylene sulfide units, phenylene sulfide sulfone units, and phenylene sulfide. Ketone unit, phenylene sul A homopolymer or copolymer comprising a phydeether unit and a biphenylene sulfide unit can be mentioned. Specific examples of the polyarylene sulfide resin include poly (p-phenylene sulfide), polyphenylene sulfide sulfone, polyphenylene sulfide ketone, Examples thereof include polyphenylene sulfide ether, and among them, poly (p-phenylene sulfide) is preferable because a polyarylene sulfide resin composition having particularly excellent heat resistance and strength characteristics is obtained.

And since the polyarylene sulfide resin (A) can obtain a polyarylene sulfide resin composition having particularly excellent whiteness, the lightness of a molded product compression-molded at a melting temperature of 310 ° C. and a pressure of 100 kgf / cm ² ( (L value) is 70 or more, preferably 70 or more and 90 or less. Here, when the L value is less than 70, the resulting composition is inferior in white color tone.

  The polyarylene sulfide resin (A) has a melt viscosity of 50 to 1000 as measured with a Koka flow tester equipped with a die having a diameter of 1 mm and a length of 2 mm at a measurement temperature of 315 ° C. and a load of 10 kg. Poise's polyarylene sulfide resin. Here, when the polyarylene sulfide resin has a melt viscosity of less than 50 poise, the resulting composition is inferior in impact resistance. On the other hand, in the case of a polyarylene sulfide resin having a melt viscosity exceeding 1000 poise, an effect of preventing generation is hardly exhibited in the eyes when the composition is produced, and the resulting composition is inferior in molding fluidity.

  The polyarylene sulfide resin (A) can be produced by a method known as a polyarylene sulfide resin production method. For example, an alkali metal sulfide or polyhaloaromatic compound in a polar solvent. Can be obtained by polymerizing. Examples of the polar organic solvent in this case include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, cyclohexyl pyrrolidone, dimethylformamide, dimethylacetamide and the like. Examples include sodium, rubidium sulfide, and lithium sulfide anhydrides or hydrates. Moreover, as an alkali metal sulfide metal salt, you may react the alkali metal hydrosulfide salt and the alkali metal hydroxide. Examples of the polyhaloaromatic compound include p-dichlorobenzene, p-dibromobenzene, p-diiodobenzene, m-dichlorobenzene, m-dibromobenzene, m-diiodobenzene, 4,4′-dichlorodiphenylsulfone, 4 4,4'-dichlorobenzophenone, 4,4'-dichlorodiphenyl ether, 4,4'-dichlorodibiphenyl, and the like.

  In addition, the polyarylene sulfide resin (A) may be a linear one, a polyhalogen compound of trihalogen or higher added during polymerization to introduce a slight cross-linked or branched structure, and the molecular chain of the polyarylene sulfide resin. A part and / or terminal of the product is modified with a functional group such as a carboxyl group, a carboxy metal salt, an alkyl group, an alkoxy group, an amino group, or a nitro group, or a heat treatment in a non-oxidizing inert gas such as nitrogen. And a mixture of these polyarylene sulfide resins may be used. The polyarylene sulfide resin (A) is washed with an acid, hot water or an organic solvent such as acetone or methyl alcohol, so that sodium atoms, oligomers of polyarylene sulfide resin, salt, 4- (N Impurities such as sodium salt of -methyl-chlorophenylamino) butanoate may be reduced.

  The white pigment (B) constituting the polyarylene sulfide resin composition of the present invention improves the white color tone of the polyarylene sulfide resin composition, and is selected from the group consisting of titanium oxide, zinc oxide, and zinc sulfide. At least one or more white pigments. The shape of the white pigment (B) is not particularly limited, and may be, for example, isotropic such as spherical, or may be fiber, spindle, rod, needle, cylinder, column, plate It may exhibit anisotropy such as a shape. Further, the white pigment (B) can be used either with or without its surface coated, and there is no particular limitation on the surface coating agent when the surface is coated. .

  The white pigment (B) is blended in an amount of 10 to 100 parts by weight of the polyarylene sulfide resin (A) because the polyarylene sulfide resin composition is excellent in white color tone and excellent in molding fluidity. ~ 50 parts by weight. Here, when the amount of the white pigment (B) is less than 10 parts by weight, the resulting composition is not preferable because the white color tone is inferior. On the other hand, when the white pigment (B) exceeds 50 parts by weight, the resulting composition is inferior in molding fluidity and impact resistance, and the effect of improving the white tone with respect to an increase in the blending amount is extremely small. .

  The glass fiber (C) constituting the polyarylene sulfide resin composition of the present invention improves the strength and impact resistance of the polyarylene sulfide resin composition, and the glass fiber (C) is generally a glass fiber. Any one may be used as long as it is called. Specific examples of the glass fibers include chopped strands having an average fiber diameter of 6 to 14 μm, chopped strands composed of flat glass fibers having an aspect ratio of 2 to 4 in the fiber cross section, glass fibers such as milled fibers and rovings; silane fibers Aluminosilicate glass fiber; hollow glass fiber; non-hollow glass fiber, and the like. Among them, since it becomes a polyarylene sulfide resin composition excellent in impact resistance and molding fluidity, the aspect ratio of the fiber cross section is 2 It is preferable that it is a chopped strand which consists of flat glass fiber which is -4. As a chopped strand having a fiber cross-section aspect ratio of 4, for example, (trade name) CSG-3PA 830 (manufactured by Nittobo Co., Ltd.), as a chopped strand having a fiber cross-section aspect ratio of 2, (trade name) And CSG-3PL 830 (manufactured by Nittobo Co., Ltd.). Two or more kinds of these glass fibers (C) can be used in combination, and if necessary, surface treatment is performed in advance with a functional compound or polymer such as an epoxy compound, an isocyanate compound, a silane compound, or a titanate compound. A thing may be used. The blending amount of the glass fiber (C) is, in particular, a polyarylene sulfide resin composition having an excellent balance between strength characteristics and molding fluidity, and therefore, 20 parts per 100 parts by weight of the polyarylene sulfide resin (A). ~ 40 parts by weight. Here, when the glass fiber is less than 20 parts by weight, the resulting composition is inferior in strength characteristics and impact resistance. On the other hand, when the glass fiber exceeds 40 parts by weight, the resulting composition is inferior in molding fluidity.

  The 12-hydroxystearic acid metal salt (D) constituting the polyarylene sulfide resin composition of the present invention suppresses the appearance of the polyarylene sulfide resin composition, thereby preventing the polyarylene sulfide resin composition. The 12-hydroxystearic acid metal salt includes, for example, lithium 12-hydroxystearate, calcium 12-hydroxystearate, magnesium 12-hydroxystearate, zinc 12-hydroxystearate and the like. Among them, among them, a polyarylene sulfide resin composition having excellent white color tone and excellent molding processability is obtained, and therefore, selected from 12-hydroxymagnesium stearate and 12-hydroxyzinc stearate 1 It is preferably not less than.

  The blending amount of the 12-hydroxystearic acid metal salt (D) is, in particular, a polyarylene sulfide resin composition excellent in white color tone and excellent in molding processability. Therefore, 100 parts by weight of the polyarylene sulfide resin (A) Is 0.05 to 2 parts by weight. Here, when the 12-hydroxystearic acid metal salt (D) is less than 0.05 parts by weight, the effect of suppressing eyes and eyes during production of the composition is poor, and the resulting composition is preferably inferior in white color tone. Absent. Moreover, when 12-hydroxy stearic acid metal salt (D) exceeds 2 weight part, while the composition obtained will be inferior to moldability, the improvement effect of the white color tone with respect to the increase in a compounding quantity will become remarkably small.

  Since the polyarylene sulfide resin composition of the present invention is particularly excellent in impact resistance, it is preferable to further blend the modified ethylene copolymer (E). Examples of the modified ethylene copolymer include ethylene-α, β-unsaturated carboxylic acid alkyl ester-maleic anhydride copolymer, ethylene-α, β-unsaturated carboxylic acid glycidyl ester copolymer, ethylene-α, β-unsaturated carboxylic acid glycidyl ester-vinyl acetate copolymer, ethylene-α, β-unsaturated carboxylic acid glycidyl ester-α, β-unsaturated carboxylic acid alkyl ester copolymer and maleic anhydride graft-modified ethylene-α -It is preferably at least one modified ethylene copolymer selected from the group consisting of olefin copolymers. The amount of the modified ethylene copolymer (E) is preferably 15 to 40 parts by weight with respect to 100 parts by weight of the polyarylene sulfide resin (A).

  Since the polyarylene sulfide resin composition of the present invention is particularly excellent in moldability, it is preferable to further blend a mold release agent (F). The release agent (F) is preferably at least one selected from fatty acid amide lubricants and carnauba wax, and commercially available fatty acid amide lubricants and carnauba waxes can be used. Examples of the fatty acid amide-based lubricant include higher fatty acid amides, ethylene bis-stearamide, polycondensates composed of higher fatty acids and diamines, and any of those belonging to this category can be used. (Trade name) Light Amide WH-255 (manufactured by Kyoeisha Chemical Co., Ltd.), which is a polycondensate composed of stearic acid, sebacic acid, and ethylenediamine. As the carnauba wax, any carnauba wax can be used as long as it is generally called carnauba wax. Examples thereof include (trade name) refined carnauba powder No. 1 (manufactured by Nikko Rica Co., Ltd.) and the like. Can do. As a compounding quantity of this mold release agent (F), it is preferable that it is 0.1-3 weight part with respect to 100 weight part of polyarylene sulfide resin (A).

  The polyarylene sulfide resin composition of the present invention is a calcium carbonate, lithium carbonate, magnesium carbonate, zinc carbonate, mica, silica, talc, clay, calcium sulfate, kaolin, wollastonite, zeolite as long as the effects of the present invention are not impaired. Silicon oxide, magnesium oxide, zirconium oxide, tin oxide, magnesium silicate, calcium silicate, calcium phosphate, magnesium phosphate, hydrotalcite, glass powder, glass balloon, and glass flakes may be added.

  In addition, the polyarylene sulfide resin composition of the present invention is a plasticizer such as a polyalkylene oxide oligomer compound, a thioether compound, an ester compound, an organic phosphorus compound, and the like as long as the effects of the present invention are not impaired. One or more usual additives such as a heat stabilizer; a lubricant; an ultraviolet light inhibitor; and a foaming agent may be added.

  Furthermore, the polyarylene sulfide resin composition of the present invention is a range of various thermosetting resins and thermoplastic resins, for example, epoxy resins, cyanate ester resins, phenol resins, polyimides, silicone resins, without departing from the object of the present invention. , Polyester, polyamide, polyphenylene oxide, polycarbonate, polysulfone, polyetherimide, polyethersulfone, polyetherketone, polyetheretherketone, polyamideimide, polyamide elastomer, polyester elastomer, polyalkylene oxide, etc. And may be used.

  The production method for producing the polyarylene sulfide resin composition of the present invention is not particularly limited, and a method known as a general mixing / kneading method can be used. For example, all raw materials are blended. Melting and kneading after mixing a part of the raw materials and then melt kneading the remaining raw materials and mixing and kneading a part of the raw materials; or melting and kneading a part of the raw materials after mixing with a single or twin screw extruder Any method such as a method of mixing the remaining raw materials using a side feeder inside may be used. Moreover, about a small amount of addition component, after kneading | mixing and pelletizing another component by said method etc., you may use it by adding before shaping | molding. As a method for performing melt kneading, a conventionally used heat melt kneading method can be used, for example, a heat melt kneading method using a single or twin screw extruder, a kneader, a mill, a Brabender, or the like. In particular, a melt-kneading method using a twin screw extruder excellent in kneading ability is preferable. Moreover, the kneading | mixing temperature in this case is not specifically limited, Usually, it can select arbitrarily from 260-350 degreeC.

  The polyarylene sulfide resin composition of the present invention is characterized by having properties such as white color tone as an exterior part, impact resistance, and excellent molding fluidity necessary for molding processing. Furthermore, the obtained polyarylene sulfide resin composition can be molded into an arbitrary shape using an injection molding machine, an extrusion molding machine, a compression molding machine, etc., and is a resin composition particularly suitable for injection molding. .

  Since the polyarylene sulfide resin composition of the present invention is particularly excellent in white color tone as an exterior part, when it is formed into a molded body that is injection-molded at a cylinder temperature of 310 ° C. and a mold temperature of 135 ° C., JIS Z8715 It is preferable that the whiteness index W measured in accordance with the above is 85 or more.

  The polyarylene sulfide resin composition of the present invention has characteristics such as white color tone as exterior parts, impact resistance, and excellent molding fluidity required for molding processing. It is suitably used for parts and the like.

  The present invention aims to improve white color tone as an exterior part by suppressing eyes and eyes in the production of a polyarylene sulfide resin composition, and is excellent in impact resistance and molding fluidity required for molding processing. The present invention provides a composition, which is useful for electrical parts such as electronic / electrical parts such as a casing of a portable terminal device such as a mobile personal computer, a tablet, and a mobile phone.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

  Polyarylene sulfide resin (A), white pigment (B), glass fiber (C), 12-hydroxystearic acid metal salt (D), modified ethylene copolymer (E), used in Examples and Comparative Examples, The release agent (F) is shown below.

<Polyarylene sulfide resin (A)>
Poly (p-phenylene sulfide) (hereinafter referred to as PPS (A-1)): melt viscosity 350 poise, lightness (L value) 82.
Poly (p-phenylene sulfide) (hereinafter referred to as PPS (A-2)): melt viscosity 470 poise, lightness (L value) 78.
Poly (p-phenylene sulfide) (hereinafter referred to as PPS (A-3)): melt viscosity 365 poise, lightness (L value) 60.

<White pigment (B)>
Titanium oxide (B-1); Ishihara Sangyo Co., Ltd. titanium oxide, (trade name) CR-60.
Zinc sulfide (B-2); manufactured by Sachtleben, (trade name) Sacritus HD.
Zinc oxide (B-3); manufactured by Hakusuitec Co., Ltd., one type of zinc oxide.

<Glass fiber (C)>
Glass fiber (C-1); chopped strand manufactured by Nittobo Co., Ltd. (trade name) CSG-3PA 830, aspect ratio 4 of fiber cross section.
Glass fiber (C-2); chopped strand manufactured by Nittobo Co., Ltd. (trade name) CSG-3PL 830, aspect ratio 2 of fiber cross section.

<12-hydroxystearic acid metal salt (D)>
12-hydroxy magnesium stearate (D-1); manufactured by Katsuta Chemical Co., Ltd. (trade name) EMS-6P.
Zinc 12-hydroxystearate (D-2); manufactured by Sakai Chemical Industry Co., Ltd. (trade name) SZ-120H.

<Modified ethylene copolymer (E)>
Ethylene-α, β-unsaturated carboxylic acid glycidyl ester-α, β-unsaturated carboxylic acid alkyl ester copolymer (E-1) (hereinafter referred to as modified ethylene copolymer (E-1)): Made by Sumitomo Chemical Co., Ltd. (trade name) Bond First 7M.
Ethylene-α, β-unsaturated carboxylic acid alkyl ester-maleic anhydride copolymer (E-2) (hereinafter referred to as modified ethylene copolymer (E-2)): manufactured by Arkema Co., Ltd. Product Name) Bondine AX8390.

<Release agent (F)>
Fatty acid amide-based lubricant (F-1) (hereinafter referred to as mold release agent (F-1)); manufactured by Kyoeisha Chemical Co., Ltd., (trade name) LIGHT AMIDE WH-255.
Carnauba wax (F-2) (hereinafter referred to as mold release agent (F-2)); manufactured by Nikko Rica Co., Ltd. (trade name), purified carnauba powder No. 1.

<Synthesis Example 1 (Synthesis of PPS (A-1))>
In a 15 liter autoclave equipped with a stirrer, 1814 g of flaky sodium sulfide (Na ₂ S · 2.9H ₂ O), 8.7 g of granular caustic soda (100% NaOH: Wako Pure Chemical), and N-methyl-2-pyrrolidone 3232 g was charged and gradually heated to 200 ° C. while stirring under a nitrogen stream, and 339 g of water was distilled off. After cooling to 190 ° C., 2129 g of p-dichlorobenzene and 1783 g of N-methyl-2-pyrrolidone were added, and the system was sealed under a nitrogen stream. The system was heated to 225 ° C. over 2 hours and polymerized at 225 ° C. for 1 hour, then heated to 250 ° C. over 25 minutes, and polymerized at 250 ° C. for 2 hours. Next, 509 g of distilled water was injected into this system at 250 ° C., the temperature was raised to 255 ° C., and a polymerization reaction was further performed for 2 hours. After completion of the polymerization, the mixture was cooled to room temperature, and the polymerization slurry was subjected to solid-liquid separation with a centrifugal filter. The cake was washed successively with N-methyl-2-pyrrolidone and acetone three times under a nitrogen stream, and further washed with 0.2% hydrochloric acid and warm water under a nitrogen stream. The obtained poly (p-phenylene sulfide) was dried overnight at 105 ° C. to obtain PPS (A-1) having a melt viscosity of 350 poise.
<Synthesis Example 2 (Synthesis of PPS (A-2))>
In a 15 liter autoclave equipped with a stirrer, 1814 g of flaky sodium sulfide (Na ₂ S · 2.9H ₂ O), 8.7 g of granular caustic soda (100% NaOH: Wako Pure Chemical), and N-methyl-2-pyrrolidone 3232 g was charged and gradually heated to 200 ° C. while stirring under a nitrogen stream, and 340 g of water was distilled off. After cooling to 190 ° C., 2100 g of p-dichlorobenzene and 1783 g of N-methyl-2-pyrrolidone were added, and the system was sealed under a nitrogen stream. The system was heated to 225 ° C. over 2 hours and polymerized at 225 ° C. for 1 hour, then heated to 250 ° C. over 25 minutes, and polymerized at 250 ° C. for 2 hours. Next, 509 g of distilled water was injected into this system at 250 ° C., the temperature was raised to 255 ° C., and a polymerization reaction was further performed for 2 hours. After completion of the polymerization, the mixture was cooled to room temperature, and the polymerization slurry was subjected to solid-liquid separation with a centrifugal filter. The cake was washed twice successively with N-methyl-2-pyrrolidone and acetone under a nitrogen stream, and further washed with 0.2% hydrochloric acid and warm water under a nitrogen stream. The obtained poly (p-phenylene sulfide) was dried overnight at 105 ° C. to obtain PPS (A-2) having a melt viscosity of 470 poise.
<Synthesis Example 3 (Synthesis of PPS (A-3))>
A 15-liter autoclave equipped with a stirrer was charged with 1854 g of flaky sodium sulfide (Na ₂ S.2.9H ₂ O), 48 g of 30% sodium hydroxide solution (30% NaOHaq) and 3679 g of N-methyl-2-pyrrolidone, and a nitrogen stream The temperature was gradually raised to 200 ° C. with stirring, and 379 g of water was distilled off. After cooling to 190 ° C., 2140 g of p-dichlorobenzene and 985 g of N-methyl-2-pyrrolidone were added, and the system was sealed under a nitrogen stream. The system was heated to 225 ° C. over 2 hours and polymerized at 225 ° C. for 1 hour, then heated to 250 ° C. over 25 minutes, and further polymerized at 250 ° C. for 3 hours. After polymerization, N-methyl-2-pyrrolidone was recovered from the polymerization slurry under reduced pressure by distillation. The final temperature reached was 172 ° C. and the pressure was 4.6 kPa. The obtained cake was washed with 80 ° C. warm water to give a slurry concentration of 20%, and again warm water was added in the same manner to raise the temperature to 175 ° C., and the poly (p-phenylene sulfide) was washed twice. The obtained polyphenylene sulfide was dried at 105 ° C. overnight. Next, the dried polyphenylene sulfide is filled in a batch-type rotary kiln-type baking apparatus, heated to 240 ° C. in a nitrogen atmosphere, and subjected to a curing treatment by holding for 1 hour, whereby a PPS (A- 3) was obtained.

  Evaluation and measurement methods of the obtained polyarylene sulfide resin and polyarylene sulfide resin composition are shown below.

-Measurement of melt viscosity of polyarylene sulfide resin-
Measurement of melt viscosity under the conditions of a measurement temperature of 315 ° C. and a load of 10 kg using a Koka type flow tester (manufactured by Shimadzu Corporation, (trade name) CFT-500) equipped with a die having a diameter of 1 mm and a length of 2 mm. Went.

-Measurement of lightness (L value) of polyarylene sulfide resin-
A polyarylene sulfide resin is compression-molded at a melting temperature of 310 ° C. and a pressure of 100 kgf / cm ² , and then formed into a molded product of 50 mm × 50 mm × 1 mm thickness at a cooling temperature of 150 ° C., and a color difference meter (Suga Test Instruments) The brightness (L value) was measured at room temperature using a (trade name) SM color computer.

~ In the eyes ~
The raw material of the polyarylene sulfide resin composition was supplied to a 35 mmφ twin screw extruder (manufactured by Toshiba Machine, (trade name) TEM-35-102B) equipped with a strand die, and extruded as a molten strand at an extrusion rate of 10 kg / hr. . The cylinders 1 to 7 were set to 270 ° C., the cylinder 8 to 290 ° C., and the die to 300 ° C. Then, the eyes and eyes adhering to the die lip were observed, and those where no discolored eyes were observed were judged as ◯, and those which were slightly discolored were judged as ×.

-Whiteness index W measurement of polyarylene sulfide resin composition-
The polyarylene sulfide resin composition was injection-molded by an injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., (trade name) SE-75S) with a cylinder temperature of 310 ° C. and a mold temperature of 135 ° C., 70 mm × 70 mm × 2 mm The whiteness index W was measured according to JIS Z8715 using a color difference meter (manufactured by Suga Test Instruments Co., Ltd., (trade name) SM color computer). A value exceeding 85 as the whiteness index W was judged to show a practically sufficient value.

~ Measurement of impact resistance ~
A test piece for measuring Charpy impact strength was measured by an injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., (trade name) SE-75S) having a polyarylene sulfide resin composition having a cylinder temperature of 310 ° C. and a mold temperature of 135 ° C. A notch machine (made by Toyo Seiki Seisakusho Co., Ltd., (trade name) A-3 type) is used to make a notch, and a Charpy impact tester (made by Toyo Seiki Seisakusho Co., Ltd. (trade name) DG-CB type). Was measured in accordance with ISO179. A Charpy impact strength exceeding 12 kJ / m ² was judged to exhibit a practically sufficient value.

~ Measurement of molding fluidity ~
An injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., (trade name) SE75S) is mounted with a mold having a groove with a depth of 1 mm and a width of 10 mm spirally formed. The polyarylene sulfide resin composition was charged into a hopper of the injection molding machine in which the injection pressure was set to 190 MPa, the injection speed was set to maximum, the injection time was set to 1.5 seconds, and the mold temperature was set to 135 ° C. And the length which melted and flowed the spiral groove | channel in a metal mold | die was measured as molding fluidity | liquidity. A molding fluidity exceeding 150 mm was judged to exhibit a practically sufficient value.

~ Molding processability (mold contamination) ~
100 pieces of 70 mm × 70 mm × 2 mm thick molded bodies were continuously formed by injection molding, and the presence or absence of contaminants adhering in the mold cavity was observed. The case where no contaminant was found was judged as ◯, and the case where even a slight amount of contaminant was found was judged as ×. The mold contamination property was judged to be excellent in molding processability when there was no mold contamination when the state was ◯.

Example 1
For 100 parts by weight of PPS (A-1) obtained in Synthesis Example 1, 20 parts by weight of titanium oxide (B-1), 0.6 parts by weight of 12-hydroxy magnesium stearate (D-1), modified ethylene Copolymer (E-1) 20 parts by weight and mold release agent (F-1) 0.5 parts by weight were mixed in advance, and a 35 mmφ twin screw extruder equipped with a strand die (manufactured by Toshiba Machine, (trade name) ) It was put into the hopper of TEM-35-102B). On the other hand, glass fiber (C-1) was introduced from the hopper of the side feeder of the twin screw extruder so as to be 30 parts by weight with respect to 100 parts by weight of PPS (A-1), and melt-kneaded to be pelletized. A poly (p-phenylene sulfide) resin composition (hereinafter referred to as a PPS resin composition) was produced. The whiteness index W, molding fluidity and molding processability of the obtained PPS resin composition were evaluated. The evaluation results are shown in Table 1.

  The obtained PPS resin composition had a practically sufficient white color tone, and had good impact strength and moldability. Also, the molding fluidity was a practically sufficient value.

Examples 2-9
PPS (A-1, A-2), titanium oxide (B-1), zinc sulfide (B-2), zinc oxide (B-3), 12-hydroxymagnesium stearate (D-1), 12-hydroxy Zinc stearate (D-2), modified ethylene copolymers (E-1, E-2) and mold release agents (F-1, F-2) are blended in the constituent ratios shown in Table 1, and the strand Into the hopper of a 35mmφ twin screw extruder equipped with a die for use, and the glass fibers (C-1, C-2) into the hopper of the side feeder of the twin screw extruder so as to have the composition ratio shown in Table 1. A PPS resin composition was prepared by the same method as in Example 1, and evaluated by the same method as in Example 1. The evaluation results are shown in Table 1.

  All of the obtained PPS resin compositions had a practically sufficient white color tone, and had good impact strength and moldability. Also, the molding fluidity was a practically sufficient value.

比較例１〜６
ＰＰＳ（Ａ−１、Ａ−３）、酸化チタン（Ｂ−１），硫化亜鉛（Ｂ−２）、ガラス繊維（Ｃ−１）、１２−ヒドロキシステアリン酸マグネシウム（Ｄ−１）、変性エチレン系共重合体（Ｅ−１）及び離型剤（Ｆ−１）を表２に示す構成割合で配合して、ストランド用ダイスを装備した３５ｍｍφ２軸押出機のホッパーに投入し、ガラス繊維（Ｃ−１）を、表２に示す構成割合になるように、２軸押出機のサイドフィーダーのホッパーに投入し、実施例１と同様の方法によりＰＰＳ樹脂組成物を作製し、実施例１と同様の方法により評価した。評価結果を表２に示す。

Comparative Examples 1-6
PPS (A-1, A-3), titanium oxide (B-1), zinc sulfide (B-2), glass fiber (C-1), magnesium 12-hydroxystearate (D-1), modified ethylene The copolymer (E-1) and the release agent (F-1) were blended in the constituent ratios shown in Table 2, and charged into a hopper of a 35 mmφ twin-screw extruder equipped with a strand die. 1) was put into the hopper of the side feeder of the twin-screw extruder so as to have the composition ratio shown in Table 2, and a PPS resin composition was produced in the same manner as in Example 1, and the same as in Example 1 The method was evaluated. The evaluation results are shown in Table 2.

  The PPS compositions obtained in Comparative Examples 1 and 3 did not have practically sufficient performance in terms of impact resistance and molding fluidity. When the PPS composition obtained in Comparative Example 4 was extruded as a molten strand, adhesion to the eyes and the die slip was recognized, and practically sufficient performance was not obtained even in white color tone. The PPS compositions obtained in Comparative Example 2 and Comparative Example 6 did not have practically sufficient performance in white color tone. In the PPS composition obtained in Comparative Example 5, contaminants were observed in the mold after molding, and practically sufficient performance was not obtained in molding processability.

  The polyarylene sulfide resin composition of the present invention is excellent in white color tone, impact resistance, and molding fluidity as an exterior part, and in particular, the electrical / electricity of a casing of a mobile terminal device such as a mobile personal computer, a tablet, or a mobile phone. It is expected as a resin composition used for electronic parts or electric parts such as automobile electrical parts.

Claims (5)

Using a Koka flow tester equipped with a die with a diameter of 1 mm and a length of 2 mm, the lightness (L value) of the molded product compression-molded at a melting temperature of 310 ° C. and a pressure of 100 kgf / cm ² is measured at a measuring temperature. At least 1 selected from the group consisting of titanium oxide, zinc oxide and zinc sulfide with respect to 100 parts by weight of polyarylene sulfide resin (A) having a melt viscosity of 50 to 1000 poise measured at 315 ° C. and a load of 10 kg White pigment (B) of 10 to 50 parts by weight, 20 to 40 parts by weight of glass fiber (C), and 12- hydroxystearic acid metal salt which is 12- hydroxy magnesium stearate and / or zinc 12-hydroxystearate ( D) A polyarylene sulfide resin composition comprising 0.05 to 2 parts by weight. For 100 parts by weight of the polyarylene sulfide resin (A), an ethylene-α, β-unsaturated carboxylic acid alkyl ester-maleic anhydride copolymer, an ethylene-α, β-unsaturated carboxylic acid glycidyl ester copolymer , Ethylene-α, β-unsaturated carboxylic acid glycidyl ester-vinyl acetate copolymer, ethylene-α, β-unsaturated carboxylic acid glycidyl ester-α, β-unsaturated carboxylic acid alkyl ester copolymer and maleic anhydride 2. The composition according to claim 1, comprising 15 to 40 parts by weight of at least one modified ethylene copolymer (E) selected from the group consisting of graft-modified ethylene-α-olefin copolymers. A polyarylene sulfide resin composition. In addition to 100 parts by weight of the polyarylene sulfide resin (A), it further contains 0.1 to 3 parts by weight of at least one release agent (F) selected from the group consisting of fatty acid amide lubricants and carnauba wax. The polyarylene sulfide resin composition according to claim 1 or 2, wherein The polyarylene sulfide resin composition according to any one of claims 1 to 3, wherein the whiteness index W measured in accordance with JIS Z8715 is 85 or more . 5. The polyarylene sulfide resin composition according to claim 4 , wherein a molded product obtained by injection molding at a cylinder temperature of 310 ° C. and a mold temperature of 135 ° C. has a whiteness index W of 85 or more .