Polyarylene sulfide resin composition and molded article obtained by molding therefrom

Abstract

The present invention provides a resin composition that exhibits excellent extrudeability, thin-wall moldability, and electromagnetic wave shielding properties. [Solution] A resin composition characterized by containing 100 parts by weight of component (A), which consists of 90 to 99.9 parts by weight of polyarylene sulfide resin (component A-1) containing nonpolar functional groups at its ends and 0.1 to 10 parts by weight of at least one organophosphorus flame retardant (component A-2), and 5 to 50 parts by weight of (B) metal-coated carbon fiber (component B).

Description

Technical Field

[0001] The present invention relates to a resin composition comprising a polyarylene sulfide resin, at least one organic phosphorus-based flame retardant, and metal-coated carbon fibers, and having excellent extrusion properties, thin-wall molding properties, and electromagnetic wave shielding properties.

Background Art

[0002] Many devices such as Wi-Fi and Bluetooth have come to communicate wirelessly, and offices and homes filled with electronic devices and electrical appliances are filled with electromagnetic waves. In the future, with the spread of robots and drones that require remote operation, electromagnetic compatibility (EMC countermeasures) of accepting necessary electromagnetic waves and shielding unnecessary electromagnetic waves will become increasingly important. Electronic devices that require electromagnetic shielding are products that apply digital technology, and include a wide range of products such as computers, electronic games, TV games, electronic cash registers, switching power supplies, digital clocks, digital watches, calculators, and word processors. The electromagnetic waves generated from these products are in the frequency band of 200 MHz to 1 GHz.

[0003] In recent years, with the miniaturization and weight reduction of electronic devices, and the resulting increase in circuit integration and density, malfunctions caused by electromagnetic waves have become a problem. Therefore, electronic device casings are required to have electromagnetic shielding properties to shield against external electromagnetic waves and prevent leakage of electromagnetic waves to the outside. To achieve electromagnetic shielding, the electronic device casing needs to be conductive; generally, higher conductivity results in better electromagnetic shielding. Traditionally, metals have been used for such casings, but attempts have been made to use plastics such as polyarylene sulfide resins from the perspective of processability and weight reduction. However, since plastics generally do not have the same conductivity as metals, it is necessary to impart conductivity to counter electromagnetic interference and noise. Typical methods disclosed for imparting electromagnetic shielding properties to plastics include conductive surface treatments such as plating, and methods for incorporating metal powders, metal fibers, carbon fibers, and metal-coated carbon fibers. Patent Document 1 discloses a thermoplastic resin composition containing nickel-metal coated carbon fibers, using carbon fibers obtained by adjusting the O1S / C1S ratio, measured by the ESCA method on the carbon fiber surface, to a specific range. However, this method is not useful for polyarylene sulfide resins, and its electromagnetic shielding properties are not sufficient. Furthermore, while Patent Document 2 discloses a resin composition comprising a polyarylene sulfide resin, a modified polyolefin composition, and a fibrous filler, it does not describe anything about thin-wall moldability, and its electromagnetic shielding properties are not sufficient. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 4674066 [Patent Document 2] Japanese Patent Publication No. 2022-114252 [Overview of the project] [Problems that the invention aims to solve]

[0005] The object of the present invention is to provide a resin composition that is excellent in extrudeability, thin-wall moldability, and electromagnetic wave shielding properties. [Means for solving the problem]

[0006] As a result of diligent research aimed at achieving the above objective, the present inventors have discovered that by blending metal-coated carbon fibers with a component consisting of polyarylene sulfide resin and at least one organophosphorus-based flame retardant, a resin composition with excellent extrudeability, thin-wall moldability, and electromagnetic wave shielding properties can be obtained, thus solving the above problem.

[0007] In other words, the present invention is as follows. 1. A resin composition characterized by containing 100 parts by weight of component (A), which consists of 90 to 99.9 parts by weight of polyarylene sulfide resin (component A-1) containing nonpolar functional groups at its termini and 0.1 to 10 parts by weight of at least one organophosphorus flame retardant (component A-2), and 5 to 50 parts by weight of (B) metal-coated carbon fiber (component B). 2. The resin composition according to item 1 above, characterized in that component A-1 is a polyarylene sulfide resin containing phenyl groups at its termini. 3. The resin composition according to item 1 or 2 above, characterized in that component B is nickel-coated carbon fiber. 4. A molded article obtained by molding any of the resin compositions described in item 1 to 3 above. [Effects of the Invention]

[0008] Because the resin composition of the present invention exhibits excellent extrudeability, thin-wall moldability, and electromagnetic wave shielding properties, molded articles made from the resin composition of the present invention are useful for parts requiring electromagnetic wave shielding, such as electrical and electronic equipment components and automobile parts, and the industrial effects it provides are extremely significant. [Modes for carrying out the invention]

[0009] The details of the present invention will be described below.

[0010] <Regarding Component A> Component A of the present invention is a component composed of 90 to 99.9 parts by weight of a polyarylene sulfide resin (Component A-1) containing a nonpolar functional group at the terminal and 0.1 to 10 parts by weight of at least one organic phosphorus-based flame retardant (Component A-2).

[0011] <Regarding Component A-1> The polyarylene sulfide resin used as Component A-1 of the present invention is a polyarylene sulfide resin containing a nonpolar functional group at the terminal.

[0012] Examples of the nonpolar functional group include a phenyl group, a vinyl group, an aliphatic hydrocarbon group (such as an alkyl group, a cycloalkyl group, etc.), and an aromatic hydrocarbon group (such as an aryl group, an arylene group, etc.). Among them, a phenyl group is preferable. By using a polyarylene sulfide resin containing a nonpolar functional group at the terminal, and blending at least one phosphorus-based flame retardant and metal-coated carbon fibers, the electromagnetic wave shielding property is improved.

[0013] Examples of the polyarylene sulfide resin include those composed of, as its structural units, for example, p-phenylene sulfide units, m-phenylene sulfide units, o-phenylene sulfide units, phenylene sulfide sulfone units, phenylene sulfide ketone units, phenylene sulfide ether units, diphenylene sulfide units, substituent-containing phenylene sulfide units, branched-structure-containing phenylene sulfide units, etc. Among them, those containing 70 mol% or more, particularly 90 mol% or more of p-phenylene sulfide units are preferable, and further, poly(p-phenylene sulfide) is more preferable.

[0014] The degree of dispersion (Mw / Mn), expressed as the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polyarylene sulfide resin, is preferably 2.7 or higher, more preferably 2.8 or higher, and even more preferably 2.9 or higher. If the degree of dispersion is less than 2.7, there may be an increase in burr generation during molding. There is no particular upper limit for the degree of dispersion (Mw / Mn), but it is preferably 10 or lower. Here, the weight-average molecular weight (Mw) and number-average molecular weight (Mn) are values ​​calculated in polystyrene equivalent by gel permeation chromatography (GPC). The solvent used was 1-chloronaphthalene, and the column temperature was 210°C.

[0015] The preferred method for producing polyarylene sulfide resin is the method described in U.S. Patent Nos. 4,746,758, 4,786,713, JP 2013-522385, JP 2012-233210, and Japanese Patent No. 5167276, etc.

[0016] The above manufacturing method includes an iodization step and a polymerization step. In the iodization step, an aryl compound is reacted with iodine to obtain a diiodoaryl compound. In the subsequent polymerization step, a polymerization inhibitor is used to polymerize the diiodoaryl compound with solid sulfur to produce a polyarylene sulfide resin. Iodine is generated in gaseous form in this step, which is recovered and reused in the iodization step. The iodine is essentially a catalyst.

[0017] A typical example of solid sulfur used in the aforementioned manufacturing method is cycloocta-sulfur (S8), in which eight atoms are linked together at room temperature. However, the sulfur compound used in the polymerization reaction is not limited to this form; any form that is solid or liquid at room temperature can be used.

[0018] Typical diiodoaryl compounds used in the above-mentioned manufacturing method include at least one selected from the group consisting of diiodobenzene, diiodonaphthalene, diiodobiphenyl, diiodobisphenol, and diiodobenzophenone. Derivatives of iodoaryl compounds that have alkyl or sulfone groups attached, or into which oxygen or nitrogen has been introduced, are also used. Iodoaryl compounds are classified into different isomers depending on the bond position of the iodine atom. Preferred examples of these isomers are compounds in which iodine is symmetrically located at both ends of the aryl compound molecule, such as p-diiodobenzene, 2,6-diiodonaphthalene, and p,p'-diiodobiphenyl. The content of the iodoaryl compound is preferably 500 to 10,000 parts by weight per 100 parts by weight of solid sulfur. This amount is determined considering the formation of disulfide bonds.

[0019] Typical polymerization inhibitors used in the above-mentioned manufacturing method include diphenyl sulfide, diphenyl disulfide, di-2-naphthyl disulfide, and bis(2,5-dimethylphenyl) disulfide, with diphenyl sulfide and diphenyl disulfide being preferred. By using these compounds as polymerization inhibitors, polyarylene sulfide resins containing non-polar functional groups at the ends can be produced. The content of the polymerization inhibitor is preferably 1 to 30 parts by weight per 100 parts by weight of solid sulfur. This amount is determined considering the formation of disulfide bonds.

[0020] The above manufacturing method may also use a polymerization catalyst, and a typical polymerization catalyst is a nitrobenzene-based catalyst. A preferred example of a nitrobenzene-based catalyst is at least one selected from the group consisting of 1,3-diiodo-4-nitrobenzene, 1-iodo-4-nitrobenzene, 2,6-diiodo-4-nitrophenol, iodonitrobenzene, and 2,6-diiodo-4-nitroamine. The content of the polymerization catalyst is preferably 0.01 to 20 parts by weight per 100 parts by weight of the solid sulfur. This amount is determined considering the formation of disulfide bonds.

[0021] <Regarding the A-2 component> The resin composition of the present invention contains at least one organic phosphorus flame retardant as the A-2 component.

[0022] Examples of the organic phosphorus flame retardant used as the A-2 component of the present invention include phosphazene compounds and aryl phosphate compounds, etc. One or more of these may be used, and they can be arbitrarily selected according to the purpose.

[0023] The phosphazene compound is not particularly limited as long as it does not contain a halogen atom and has a phosphazene structure composed of phosphorus atoms and nitrogen atoms in the molecule. The phosphazene structure referred to here is a structure represented by the formula: -P(R1)=N- [wherein, R1 is an organic group], and the phosphazene compound is a compound represented by general formulas (1) and (2).

[0024] [Chemical formula]

[0025] [Chemical formula] <000011A>

[0026] (In the formula, R1, R2, R3, and R4 represent an organic group that does not contain a hydrogen, hydroxyl group, amino group or halogen atom. Also, n represents an integer of 3 to 10.) I

[0027] In the above formulas (1) and (2), examples of the organic group that does not contain a halogen atom represented by R1, R2, R3, and R4 include an alkoxy group, a phenyl group, an amino group, and an allyl group, etc. As the phosphazene compound, either a linear or cyclic phosphazene compound shown in the above formulas (1) and (2) can be used, but from the viewpoint of flame retardancy, cyclic phosphazene compounds are preferred, and cyclic phenoxyphosphazene is more preferred.

[0028] While various phosphate compounds conventionally known as flame retardants can be used as aryl phosphate compounds, more preferably, one or more phosphate compounds represented by the following general formula (3) can be used.

[0029] [ka]

[0030] (In formula (3), X is a divalent phenol residue derived from a dihydroxy compound selected from the group consisting of hydroquinone, resorcinol, bis(4-hydroxydiphenyl)methane, bisphenol A, dihydroxydiphenyl, dihydroxynaphthalene, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)ketone, and bis(4-hydroxyphenyl)sulfide; n is an integer from 0 to 5, or the average value in the case of a mixture of phosphate esters with different n values; and R5, R6, R7, and R8 are each monovalent phenol residues derived from an aryl group selected from the group consisting of independent phenol, cresol, xylenol, isopropylphenol, butylphenol, and p-cumylphenol.)

[0031] The phosphate compound of general formula (3) described above may be a mixture of compounds having different n numbers, in which case the average n number is preferably in the range of 0.5 to 1.5, more preferably 0.8 to 1.2, even more preferably 0.95 to 1.15, and particularly preferably 1 to 1.14.

[0032] Suitable specific examples of divalent phenols that induce X in the above general formula (3) are resorcinol, bisphenol A, and dihydroxydiphenyl, with resorcinol and bisphenol A being preferred among them.

[0033] Preferable specific examples of the monohydric phenol that induces R5, R6, R7, and R8 in the general formula (3) above include phenol, cresol, xylenol, and 2,6-dimethylphenol, and among them, phenol and 2,6-dimethylphenol are preferable.

[0034] Preferable specific examples of the phosphate compound of the general formula (3) above include monophosphate compounds such as triphenyl phosphate and tri(2,6-xylyl) phosphate, and phosphate oligomers mainly composed of resorcinol bis(di(2,6-xylyl) phosphate), phosphate oligomers mainly composed of 4,4-dihydroxydiphenyl bis(diphenyl phosphate), and phosphate ester oligomers mainly composed of bisphenol A bis(diphenyl phosphate). Among them, phosphate oligomers mainly composed of resorcinol bis(di(2,6-xylyl) phosphate), phosphate oligomers mainly composed of 4,4-dihydroxydiphenyl bis(diphenyl phosphate), and phosphate ester oligomers mainly composed of bisphenol A bis(diphenyl phosphate) are preferable.

[0035] In the present invention, it is possible to contain other phosphorus-based flame retardants as long as the function of the organic phosphorus-based flame retardant is not hindered.

[0036] The content of the A-2 component is 0.1 to 10 parts by weight, preferably 0.5 to 9 parts by weight, and more preferably 1 to 8 parts by weight in 100 parts by weight of the A component. When the content is less than 0.1 part by weight, the thin-wall moldability and electromagnetic wave shielding property deteriorate. When it exceeds 10 parts by weight, the extrudability deteriorates and pelletization becomes difficult.

[0037] <Regarding the B component> The resin composition of the present invention contains metal-coated carbon fibers as the B component. Any carbon fiber commonly referred to as carbon fiber may be used in metal-coated carbon fiber. Examples include PAN-based carbon fiber made from polyacrylonitrile, pitch-based carbon fiber made from petroleum tar or petroleum pitch, vapor-grown carbon fiber made from hydrocarbons, and cellulose-based carbon fiber made from viscose rayon.

[0038] The metals formed on the carbon fiber surface include silver, copper, iron, nickel, and aluminum, with nickel being preferred from the viewpoint of corrosion resistance of the metal layer. Known methods for metal coating include plating and vapor deposition, with plating being particularly preferred. The thickness of the metal coating layer is preferably 0.1 to 1 μm, more preferably 0.15 to 0.5 μm, and even more preferably 0.2 to 0.35 μm.

[0039] The number-average fiber length in the resin composition of component B is preferably 60 to 500 μm, more preferably 80 to 400 μm, and even more preferably 100 to 300 μm. If the number-average fiber length is less than 60 μm, sufficient electromagnetic shielding may not be obtained. On the other hand, if it exceeds 500 μm, the thin-wall moldability may deteriorate. The number-average fiber length is calculated by an image analysis device from optical microscope observation of carbon fiber residue collected from treatments such as high-temperature ashing, dissolution with solvents, and decomposition with chemicals of the molded product. Furthermore, in calculating this value, fibers with a length less than or equal to the fiber diameter are not counted.

[0040] The content of component B is 5 to 50 parts by weight, preferably 8 to 47 parts by weight, and more preferably 10 to 45 parts by weight, per 100 parts by weight of component A. If the content is less than 5 parts by weight, sufficient electromagnetic shielding cannot be obtained. On the other hand, if the content exceeds 50 parts by weight, the extrudeability deteriorates and pelletization becomes difficult.

[0041] <Other ingredients> The resin composition in the present invention may be used in combination with inorganic fillers other than component B, as long as the effects of the present invention are not impaired. Examples of inorganic fillers include fibrous fillers other than component B, powdered fillers, and plate-shaped fillers. Examples of fibrous fillers include glass fibers, aramid fibers, potassium titanate whiskers, zinc oxide whiskers, alumina fibers, silicon carbide fibers, ceramic fibers, asbestos fibers, gypsum fibers, metal fibers, and inorganic fibers coated with non-metallic conductive materials. Specific examples of conductive materials in inorganic fibers coated with non-metallic conductive materials include SnO2 (antimond dope) and In2O3 (antimond dope). Examples of inorganic fibers to be coated include glass fibers, potassium titanate whiskers, zinc oxide whiskers, titanate-based whiskers, and silicon carbide whiskers. Examples of coating methods include vacuum deposition, sputtering, electroless plating, and baking. These may also be surface-treated with surface treatment agents such as titanate-based, aluminum-based, and silane-based coupling agents. Furthermore, pre-treating these fibrous fillers with coupling agents such as isocyanate compounds, organosilane compounds, organotitanate compounds, organoborane compounds, and epoxy compounds is preferable in order to obtain superior mechanical strength. Examples of powdered fillers include carbon black, calcium carbonate, silica, titanium dioxide, graphite, carbon nanotubes, and metal powders, while examples of plate-like fillers include talc and mica.

[0042] The resin composition in the present invention may contain thermoplastic resins other than component A-1, to the extent that the effects of the present invention are not impaired. Examples of thermoplastic resins other than component A-1 include general-purpose plastics such as polyethylene resin, polypropylene resin, and polyalkyl methacrylate resin; engineering plastics such as polyphenylene ether resin, polyacetal resin, cyclic polyolefin resin, and polyarylate resin (amorphous polyarylate, liquid crystalline polyarylate); and so-called super engineering plastics such as polytetrafluoroethylene, polyetheretherketone, polyetherimide, polysulfone, and polyethersulfone.

[0043] The resin composition in this invention may contain, to the extent that it does not impair the effects of the present invention, antioxidants and heat stabilizers (hindered phenols, hydroquinones, phosphates and their derivatives, etc.), weathering agents (resorcinols, salicylates, benzotriazoles, benzophenones, hindered amines, etc.), mold release agents, lubricants (montanic acid and its metal salts, its esters, its half-esters, stearyl alcohol, stearamides, various bisamides, bisurea and polyethylene wax, etc.), pigments (cadmium sulfide, phthalocyanine, carbon black, etc.), dyes (nigrosine, etc.), nucleating agents (talc, silica, kaolin, clay, etc.), and plasticizers (p-oxide). Other additives may include octyl cybenzoate, N-butylbenzenesulfonamide, etc., antistatic agents (alkyl sulfate anionic antistatic agents, quaternary ammonium salt cationic antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine-based amphoteric antistatic agents, etc.), flame retardants other than component A-2 (red phosphorus, melamine cyanurate, hydroxides such as magnesium hydroxide and aluminum hydroxide, ammonium polyphosphate, brominated polystyrene, brominated polyphenylene ether, brominated polycarbonate, brominated epoxy resin, or combinations of these brominated flame retardants with antimony trioxide, etc.), and other polymers.

[0044] <Method for producing resin compositions> The resin composition of the present invention can be manufactured by mixing the above components simultaneously or in any order using a mixer such as a tumbler, V-type blender, Nauter mixer, Banbury mixer, kneading roll, and extruder. Preferably, melt kneading is performed using a twin-screw extruder, and if necessary, it is preferable to supply any component into the other molten-mixed components from a second supply port using a side feeder or the like.

[0045] As described above, the extruded resin is either directly cut and pelletized, or strands are formed and then these strands are cut in a pelletizer to form pellets. If it is necessary to reduce the influence of external dust and other contaminants during pelletization, it is preferable to clean the atmosphere around the extruder. The resulting pellets can take on common shapes such as cylinders, prismatics, and spheres, but cylinders are more preferable. The diameter of such cylinders is preferably 1 to 5 mm, more preferably 1.5 to 4 mm, and even more preferably 2 to 3.5 mm. On the other hand, the length of the cylinders is preferably 1 to 30 mm, more preferably 2 to 5 mm, and even more preferably 2.5 to 4 mm.

[0046] <Molded products> Molded articles made from the resin composition of the present invention can be obtained by molding pellets manufactured as described above. Preferably, they can be obtained by injection molding or extrusion molding. In injection molding, not only conventional molding methods but also injection compression molding, injection press molding, gas-assisted injection molding, foam molding (including the method of injecting supercritical fluid), insert molding, in-mold coating molding, heat-insulating mold molding, rapid heating and cooling mold molding, two-color molding, multi-color molding, sandwich molding, and ultra-high-speed injection molding can be used. Furthermore, both cold runner and hot runner molding methods can be selected. In extrusion molding, various irregularly shaped extruded articles, sheets, films, etc. can be obtained. For molding sheets and films, inflation, calendering, and casting methods can also be used. Furthermore, it is possible to mold them as heat-shrinkable tubes by applying specific stretching operations. It is also possible to mold the resin composition of the present invention into molded articles by rotational molding or blow molding. Furthermore, various surface treatments can be applied to molded articles manufactured by the above various methods. Surface treatment as used here refers to forming a new layer on the surface of a resin molded product, such as vapor deposition (physical vapor deposition, chemical vapor deposition, etc.), plating (electroplating, electroless plating, hot-dip plating, etc.), painting, coating, and printing, and various methods used for resin molded products can be applied. Furthermore, by further applying various vacuum forming, hot press forming, and bending processes to sheet molded products (including ribbon-shaped molded products), various transport containers and electromagnetic shielding covers can also be manufactured. [Examples]

[0047] The present invention will be described below based on examples. However, the present invention is not limited to the following examples, and the following examples can be modified or altered in accordance with the spirit of the invention, without excluding them from the scope of the invention. (1) Extrusion The extrusion properties during pellet production were evaluated as follows. ○: Can be made into pellets. ×: Difficult to pelletize. (2) Thin wall formability Using the square plate (size: 150 mm × 150 mm × 1 mm t) obtained by the following method, the formability was evaluated as follows. A: It can be formed without problems. B: The fluidity is low and it cannot be filled sufficiently. (3) Number average fiber length of component B The central part (size: 50 mm × 50 mm × 2 mm t) of the square plate (size: 150 mm × 150 mm × 2 mm t) obtained by the following method was cut out, ashed at 500 °C, and component B was taken out. A part (about 1000 pieces) of the taken-out component B was observed with a scanner-type image analyzer (manufactured by Jasco International Co., Ltd.), and the number average fiber length was obtained without counting those with lengths below the fiber diameter. (4) Electromagnetic shielding property Using the square plate (size: 150 mm × 150 mm × 2 mm t) obtained by the following method, the shielding effects (dB) of the electric field and magnetic field in the region of 100 kHz to 1 GHz were measured with a network analyzer (manufactured by Keysight Technologies) and a KEC method measuring device (manufactured by JSE), and the highest electric field shielding effect (dB) and magnetic field shielding effect (dB) in the region of 200 MHz to 1 GHz were calculated. In addition, the following materials were used in the examples and comparative examples of the present invention.

[0048] <A-1 component> A-1-1: Polyphenylene sulfide resin obtained by production method 1 [Production method 1] 300.00 g of para-diiodobenzene and 27.00 g of sulfur were charged with 0.60 g of diphenyldisulfide (content of 0.65% by weight based on the weight of the finally polymerized PPS) as a polymerization terminator, heated to 180 °C to completely melt and mix them, then the temperature was raised to 220 °C, and the pressure was reduced to 200 Torr. The obtained mixture was subjected to a polymerization reaction for 8 hours while gradually changing the temperature and pressure so that the final temperature and pressure were 320 °C and 1 Torr, respectively, to obtain a polyphenylene sulfide resin containing a phenyl group at the terminal. A-1-2 (comparative example): Polyphenylene sulfide resin obtained by production method 2 [Manufacturing Method 2] Charge 1814 g of flaky sodium sulfide (Na2S·2.9H2O), 8.7 g of granular caustic soda (100% NaOH: Wako Pure Chemical Industries, special grade), and 3232 g of N-methyl-2-pyrrolidone into a 15-liter autoclave equipped with a stirrer. Gradually heat the mixture to 200 °C while stirring under a nitrogen stream, and distill off 339 g of water. After cooling to 190 °C, add 2129 g of p-dichlorobenzene and 1783 g of N-methyl-2-pyrrolidone, and enclose the system under a nitrogen stream. Heat this system to 225 °C over 2 hours, polymerize it at 225 °C for 1 hour, then heat it to 250 °C over 25 minutes and carry out polymerization at 250 °C for 2 hours. Next, inject 509 g of distilled water into this system at 250 °C, heat it to 255 °C, and further carry out a polymerization reaction for 2 hours. After the polymerization is completed, cool it to room temperature, and separate the solid and liquid of the polymerization slurry with a centrifugal filter. Wash the cake successively 3 times with N-methyl-2-pyrrolidone and acetone under a nitrogen stream, and further wash it successively with 0.2% hydrochloric acid and warm water under a nitrogen stream. By drying the obtained poly(p-phenylene sulfide) at 105 °C for one day and night, a polyarylene sulfide resin that does not contain a phenyl group at the end and contains a thiol group is obtained.

[0049] A - 2 - 1: FCX - 210 (manufactured by Teijin Ltd., 2,4,8,10 - tetraoxa - 3,9 - diphosphaspiro[5,5]undecane, 3,9 - dibenzyl - 3,9 - dioxide) A - 2 - 2: FP - 110T (manufactured by Fushimi Pharmaceutical Co., Ltd., cyclic phenoxyphosphazene) A - 2 - 3: PX - 200 (manufactured by Daihachi Chemical Industry Co., Ltd., resorcinol bis(di - 2,6 - xylyl phosphate)) A - 2 - 4: Adeka Stab FP500 (phosphate ester manufactured by ADEKA Corporation) A - 2 - 5: TPP (phosphate ester manufactured by Daihachi Chemical Industry Co., Ltd.) A - 2 - 6: CR - 741 (phosphate ester manufactured by Daihachi Chemical Industry Co., Ltd.)

[0050] B-1: Tenax-J HT C923 (manufactured by Teijin Limited; fiber diameter: 7.5 μm, cut length: 6 mm; nickel-metal coated carbon fiber) B-2 (Comparative Example): Tenax-J HT C432 (manufactured by Teijin Limited; fiber diameter: 7 μm, cut length: 6 mm; carbon fiber) (Preparation of test specimens)

[0051] [Examples 1-14, Comparative Examples 1-6] Components A-1 and A-2 were supplied from the first feed port, and component B was supplied from the second feed port using a side feeder, and then melted and extruded to form pellets. Here, the first feed port is the feed port at the base, and the second feed port is the feed port located between the extruder die and the first feed port. Melt extrusion was carried out using a 30 mmφ vented twin-screw extruder with side screws [(TEX30α-38.5BW-3V, manufactured by Japan Steel Works Ltd.)]. The extrusion temperatures were set to C1 / C2 / C3~C11 / D = 50℃ / 280℃ / 300℃ / 300℃, the main screw rotation speed was 200 rpm, the side screw rotation speed was 80 rpm, the discharge rate was 20 kg / h, and the vent pressure was 3 kPa. The pellets were dried at 130°C for 6 hours using a hot air circulation dryer, and then 150mm x 150mm x 2mmt square plates and 150mm x 150mm x 1mmt square plates were produced using an injection molding machine (EC130SXII-4Y manufactured by Toshiba Machine Engineering Co., Ltd.) at a cylinder temperature of 300°C and a mold temperature of 140°C.

[0052] The extrudeability, thin-wall formability, and electromagnetic shielding properties described above were evaluated for each example and comparative example. The results are shown in Tables 1 and 2.

[0053] [Table 1]

[0054] [Table 2]

[0055] <Examples 1-14> By blending a polyarylene sulfide resin within the scope of the present invention with at least one organophosphorus flame retardant and metal-coated carbon fibers, excellent extrudeability, thin-wall moldability, and excellent electromagnetic shielding properties with both electric field shielding and magnetic field shielding effects exceeding 40 dB were observed. <Comparative Example 1> Because it does not contain component A-2, the thin-wall moldability and electromagnetic shielding properties have deteriorated. <Comparative Example 2> Because the content of component A-2 exceeded the upper limit, the extrusion properties deteriorated and pellets could not be obtained. <Comparative Example 3> Because it does not contain component B, the electromagnetic shielding performance has deteriorated. <Comparative Example 4> Because the content of component B exceeded the upper limit, the extrusion properties deteriorated and pellets could not be obtained. <Comparative Example 5> Because component A-1 is a different component from the one claimed, the electromagnetic shielding performance deteriorated. <Comparative Example 6> Because component B is a different component from what is claimed, the electromagnetic shielding performance deteriorated.

Claims

1. A resin composition characterized by containing 100 parts by weight of component (A), which consists of 90 to 99.9 parts by weight of polyarylene sulfide resin (component A-1) containing nonpolar functional groups at its termini and 0.1 to 10 parts by weight of at least one organophosphorus flame retardant (component A-2), and 5 to 50 parts by weight of (B) metal-coated carbon fiber (component B).

2. The resin composition according to claim 1, characterized in that component A-1 is a polyarylene sulfide resin containing phenyl groups at its termini.

3. The resin composition according to claim 1 or 2, characterized in that component B is nickel-coated carbon fiber.

4. A molded article obtained by molding the resin composition according to claim 1 or 2.

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