Polyarylene sulfide composition

Abstract

Provided is a polyarylene sulfide composition and an insulated wire suitable for applications such as coating materials and resin pipes because of excellent dielectric characteristics and partial discharge inception voltage and excellent adhesion and coating properties without impairing the inherent heat resistance of polyarylene sulfide.　This polyarylene sulfide composition contains 5-45 parts by weight of a saponified ethylene-vinyl acetate copolymer (B) and 10-45 parts by weight of a high-pressure low-density polyethylene (C) relative to 100 parts by weight of a polyarylene sulfide (A), and has a melt viscosity of 2,000-8,000 poise at 290°C and a load of 10 Kg.

Description

Polyarylene sulfide composition

[0001] The present invention relates to a polyarylene sulfide composition that is excellent in dielectric properties and partial discharge inception voltage, and also in toughness such as tensile break strength and impact resistance, without impairing the heat resistance inherent to polyarylene sulfide, and relates to a polyarylene sulfide composition that is particularly useful for applications such as coating materials, resin pipes, and insulated electric wires, which are produced by extrusion molding and have excellent dielectric withstand voltage.

[0002] The automotive industry is working to develop elemental technologies for increasing the efficiency, size, and weight of many motors and generators installed in electric vehicles, such as those used to drive hybrid vehicles and electric vehicles. One method for achieving higher output is to increase the coil's space factor within the stator core. One way to increase this coil's space factor is to use rectangular wire with a rectangular cross section instead of the round wire that has been commonly used as the coil wire. In this case, the insulating wire coating material is required to have not only long-term heat resistance but also dielectric breakdown strength, especially a high partial discharge inception voltage. The relationship between partial discharge inception voltage and relative permittivity is expressed by the following formula (1) (Dakin's formula). According to formula (1), in order for the wire to have a high partial discharge inception voltage, the insulating coating material must have a low relative permittivity relative to the resin composition. V = 163 (t / εr) ０．４６ (1) (where V is the partial discharge inception voltage (Vrms), t is the thickness of the insulating layer (μm), and εr is the relative dielectric constant of the insulating layer.)

[0003] Furthermore, electric wires used for such applications are continuously formed by extrusion molding, followed by bending, and the end faces of the electric wires are electrically connected by spot welding to form a single long wire. The resin composition used as the insulating coating is also required to have flexibility during bending of the electric wire and adhesion to the conductor. The resin composition used for such an insulating coating or the insulated electric wire produced using the same contains polyarylene sulfide (I) and tetrafluoroethylene / hexafluoropropylene copolymer (II), and the average particle size of the fluororesin (II) is 0.1 μm or more and less than 2.5 μm, and the fluororesin (II) has a carbonyl group at the end of its main chain and has 10 carbon atoms. ６ and an insulated wire (see, for example, Patent Document 1) which is characterized in that the fluorine resin (II) has a melting point of 230°C to 350°C. Also proposed is an insulated wire comprising a conductor and an insulating layer provided around the conductor, the insulating layer having an inner layer and an outer layer, the inner layer being formed from a halogen-free resin composition containing a base polymer (A) containing a thermoplastic resin (a1) which has an aromatic ring in the main chain and does not contain nitrogen atoms, and the outer layer being formed from a crosslinked product obtained by crosslinking a halogen-free flame-retardant resin composition containing a base polymer (B) containing a polyolefin component and a halogen-free flame retardant (see, for example, Patent Document 2).

[0004] Further, a resin composition (see, for example, Patent Document 3) has been proposed, which comprises a polyphenylene sulfide resin (A) and a resin (B) composed of an olefin copolymer resin consisting of at least one member selected from the group consisting of ethylene copolymers (B1) composed of polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, and ethylene glycidyl methacrylate copolymer, resins (B2) composed of isotactic polypropylene, syndiotactic polypropylene, and polymethylpentene, and resins (B3) obtained by modifying resin (B2) with maleic anhydride or glycidyl methacrylate. Also proposed is an insulated electric wire (see, for example, Patent Document 4) which is composed of two or more resin layers as an insulating coating layer, comprising at least one thermosetting resin layer as an inner layer and at least one thermoplastic resin layer as an outer layer, the thermosetting resin being selected from polyamideimide and polyimide, and the thermoplastic resin containing polyether ether ketone or polyphenylene sulfide.

[0005] Furthermore, in order to further improve insulation performance, there is a demand for not only coating materials but also resin pipes with excellent dielectric strength.

[0006] Japanese Patent No. 5737464 Japanese Patent No. 6816419 Japanese Patent No. 5516303 Japanese Patent No. 6839695

[0007] In the insulated wire of Patent Document 1, in order to improve the partial discharge inception voltage, a fluororesin with a low relative dielectric constant is dispersed in a polyarylene sulfide matrix to reduce the dielectric constant of the resin composition, but while an improvement in the partial discharge inception voltage is achieved, the resin has poor adhesion and bonding properties, which causes gaps to form between the coating layer and the conductor, resulting in a decrease in the partial discharge inception voltage and making it difficult to ensure insulation over the long term. Similarly, the insulated wire of Patent Document 2 also has a problem with the adhesion between the conductor and the inner layer of the coating material.

[0008] The isotactic polypropylene, syndiotactic polypropylene, and polymethylpentene proposed in Patent Document 3 are all hydrocarbon polymers. While they have excellent dielectric constants and partial discharge inception voltages, their low polarity and chemical stability result in poor chemical interaction with copper wires and poor adhesion. Therefore, when extrusion-molded into electric wires, gaps may form between the copper wire and the thermoplastic resin layer due to molding shrinkage and differences in linear expansion coefficients, potentially reducing the breakdown voltage. Furthermore, electric wires with internal gaps cannot be measured by simple dimensional measurement alone, making quality assurance on the production line difficult. Furthermore, Patent Document 4 proposes a structure in which the insulation coating layer of an electric wire is composed of two or more layers, with an inner layer of a thermosetting resin that adheres well to the copper wire to prevent gaps from forming between the copper wire and the thermoplastic resin in the outer layer. However, the manufacturing process for electric wires using thermosetting resin involves dissolving or dispersing a monomer in an organic solvent, and then repeating the coating and baking processes multiple times to create a defect-free coating layer. That is, a lot of heat energy and dedicated equipment are required to heat and evaporate the organic solvent and cause the thermosetting reaction of the monomer. In addition, the working environment is poor because the solvent is volatilized, and exhaust equipment is required, which increases the amount of CO2 emitted during production. ２ This is disadvantageous in terms of emissions and energy costs. For this reason, continuous production of insulated wires by extrusion molding of a single layer of thermoplastic resin with high insulating properties is sought as the most inexpensive, environmentally friendly, and labor-intensive manufacturing method.

[0009] Therefore, there is a need for a material that not only has excellent heat resistance, insulation properties, and mechanical properties, but also does not cause problems with the coating even when the insulating coating layer is thin or the production speed is high when forming an electric wire or the like, and can be processed without causing cracks when bending is performed after forming an extrusion-molded product; a material that has excellent insulation withstand voltage properties and can be used as a coating material for bus bar components or as hollow piping (so-called tubes); and an insulated electric wire that has excellent adhesion between the coating material and the conductor and is suitable for motors and / or generators.

[0010] As a result of intensive research to solve the above-mentioned problems, the present inventors have found that a polyarylene sulfide composition containing polyarylene sulfide, saponified ethylene-vinyl acetate copolymer, and high-pressure low-density polyethylene has a low relative dielectric constant while ensuring adhesion to conductors, is compatible with relatively high-speed wire coating molding, and has excellent toughness such as tensile breaking strength and impact resistance, making it suitable for applications such as resin piping, and that when used as a coating material, it results in an insulated wire that has a certain low relative dielectric constant and excellent adhesion between the conductor and the coating material, which has led to the completion of the present invention.

[0011] That is, the present invention resides in the following [1] to

[11] . [1] A polyarylene sulfide composition comprising 5 to 45 parts by weight of a saponified ethylene-vinyl acetate copolymer (B) and 10 to 45 parts by weight of a high-pressure low-density polyethylene (C) relative to 100 parts by weight of a polyarylene sulfide (A), and having a melt viscosity of 2,000 to 8,000 poises at 290°C under a load of 10 kg. [2] The polyarylene sulfide composition according to [1], wherein the saponified ethylene-vinyl acetate copolymer (B) is a saponified ethylene-vinyl acetate copolymer having a degree of saponification of vinyl acetate units of 60% by weight or more as calculated in accordance with JIS K7192. [3] The polyarylene sulfide composition according to [1] or [2], wherein the saponified ethylene-vinyl acetate copolymer (B) is a saponified ethylene-vinyl acetate copolymer having an ethylene unit content of 65 mol% to 90 mol%. [4] The polyarylene sulfide composition according to any one of [1] to [3], wherein the high-pressure low-density polyethylene (C) is a high-pressure low-density polyethylene having a melt tension of 100 mN or more at 260°C and a molecular weight distribution of 9.0 or more as determined by gel permeation chromatography. [5] The polyarylene sulfide composition according to any one of [1] to [4], wherein the high-pressure low-density polyethylene (C) is a heat-melt-treated high-pressure low-density polyethylene. [6] The polyarylene sulfide composition according to any one of [1] to [5], further comprising an ethylene-(meth)acrylic acid ester copolymer (D). [7] An insulating coating material, which is an extrusion molded article of the polyarylene sulfide composition according to any one of [1] to [6]. [8] A resin pipe, which is an extrusion molded article of the polyarylene sulfide composition according to any one of [1] to [6]. [9] An insulated electric wire, which has the insulating coating material according to [7] on the outer periphery of a conductor.

[10] The insulated wire according to [9], wherein the insulating coating material is a single layer having a thickness of 0.05 to 0.3 mm.

[11] The insulated wire according to

[10] , wherein the conductor is made of tough pitch copper and / or pure copper and has a rectangular cross section with short sides of 0.8 to 5 mm and long sides of 1.4 to 8 mm.

[0012] The polyarylene sulfide composition of the present invention has high adhesion while having a low relative dielectric constant without impairing the heat resistance, dielectric breakdown strength, and other properties inherent to polyarylene sulfides, and is therefore suitable for use in applications such as electric / electronic parts or automobile parts, particularly applications such as coating materials for insulated electric wires, inverter bus bars, and hollow molded products such as insulating piping parts and joints. Insulated electric wires using the polyarylene sulfide composition of the present invention as a coating material have excellent heat resistance, dielectric breakdown strength, cold / heat shock cycle resistance, and toughness while ensuring adhesion between the conductor and the coating layer, and are capable of improving the motor efficiency and power generation efficiency of motors, generators, reactors, and the like, and are expected to contribute to energy conservation and miniaturization and weight reduction of electric vehicles and hybrid vehicles.

[0013] 1 is a cross-sectional view schematically showing an example of an embodiment of the insulated wire of the present invention, and FIG. 2 is a cross-sectional view schematically showing another example of an embodiment of the insulated wire of the present invention.

[0014] The present invention will be described in detail below. The PAS (A) constituting the polyarylene sulfide (hereinafter sometimes referred to as PAS) composition of the present invention may be any PAS that falls within the category generally referred to as PAS. Examples of the PAS include homopolymers or copolymers comprising p-phenylene sulfide units, m-phenylene sulfide units, o-phenylene sulfide units, phenylene sulfide sulfone units, phenylene sulfide ketone units, phenylene sulfide ether units, and biphenylene sulfide units. Specific examples of the PAS include poly(p-phenylene sulfide) (hereinafter sometimes simply referred to as PPS), polyphenylene sulfide sulfone, polyphenylene sulfide ketone, and polyphenylene sulfide ether. Among these, PPS is preferred because it provides a PAS composition that is particularly excellent in heat resistance and strength properties.

[0015] The PAS (A) can be produced by a method known for producing PAS, for example, by polymerizing an alkali metal sulfide salt and a polyhalogenated aromatic compound in an aprotic polar solvent. Examples of the polar organic solvent include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, cyclohexylpyrrolidone, dimethylformamide, and dimethylacetamide. Examples of the alkali metal sulfide salt include anhydrous or hydrated sodium sulfide, rubidium sulfide, and lithium sulfide. The alkali metal sulfide salt may also be a product obtained by reacting an alkali metal hydrosulfide salt with an alkali metal hydroxide. Examples of polyhalogenated aromatic compounds include p-dichlorobenzene, p-dibromobenzene, p-diiodobenzene, m-dichlorobenzene, m-dibromobenzene, m-diiodobenzene, 4,4'-dichlorodiphenyl sulfone, 4,4'-dichlorobenzophenone, 4,4'-dichlorodiphenyl ether, and 4,4'-dichlorodiphenyl.

[0016] Examples of PAS (A) include linear PAS, PAS obtained by heat treatment in oxygen to introduce a crosslinked or branched structure, PAS obtained by adding a small amount of a trihalogen or higher polyhalogen compound during polymerization to introduce a slight crosslinked or branched structure, PAS modified at a portion and / or end of the molecular chain 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, PAS obtained by heat treatment in a non-oxidizing inert gas such as nitrogen, and mixtures of these PAS are also acceptable. Among these, PAS modified at a portion of the molecular chain with an amino group is preferred because it has excellent interaction with a saponified ethylene-vinyl acetate copolymer having a polar group, and also excellent reactivity with reactive compounds, particularly polymers having reactive functional groups that may be blended as needed, such as an ethylene-(meth)acrylic acid ester copolymer, and thus allows for the easier production of PAS compositions having excellent toughness, such as impact resistance. The PAS may be one in which impurities such as sodium atoms, PAS oligomers, table salt, and sodium salt of 4-(N-methyl-chlorophenylamino)butanoate have been reduced by acid washing, hot water washing, or washing with an organic solvent such as acetone or methyl alcohol.

[0017] The PAS (A) preferably has a melt viscosity of 200 to 3,000 poise as measured using a high-speed flow tester equipped with a die having a diameter of 1 mm and a length of 2 mm under conditions of a measurement temperature of 315°C and a load of 10 kg, since this will result in excellent moldability when made into a PAS composition. For resin compositions to be used in extrusion molding processes such as molding of resin piping and coating materials, a melt viscosity of 400 to 3,000 poise, more preferably 500 to 2,000 poise, is preferred.

[0018] The saponified ethylene-vinyl acetate copolymer (hereinafter sometimes referred to as saponified EVA) (B) constituting the PAS composition of the present invention is a copolymer having ethylene units and vinyl alcohol structural units, which are the saponification product of vinyl acetate units (and, in some cases, unsaponified vinyl acetate units). Therefore, while having a low dielectric constant, the highly polar hydroxyl groups in the vinyl alcohol units provide excellent dispersibility in PAS. Furthermore, the copolymer exhibits excellent adhesion and bonding properties through interaction with metal oxides present on the surface of metal components, such as copper oxide on the surface of copper alloys. Such saponified EVA (B) can be obtained by saponifying EVA, an ethylene-vinyl acetate copolymer. Among these, EVA with a high degree of saponification and a high amount of hydroxyl groups is preferred, as this enhances the polarity derived from the hydroxyl groups. The degree of saponification of vinyl acetate units, calculated in accordance with JIS K7192 (1999), is preferably 60% by weight or more, more preferably 80% by weight or more, and may even be a fully saponified product of 100% by weight. In addition, the content of ethylene units is preferably 65 mol % or more and 90 mol % or less, since this makes it possible to provide a PAS composition excellent in flexibility and toughness.

[0019] Examples of the saponified EVA (B) include commercially available products such as (trade name) Mersen H6051 (manufactured by Tosoh Corporation) and (trade name) Mersen H6960 (manufactured by Tosoh Corporation). Alternatively, a saponified EVA having a desired degree of saponification may be prepared by subjecting EVA to a heat treatment with an aqueous sodium hydroxide solution. Examples of EVA include (trade name) Ultrathene 751 (vinyl acetate content: 28%) (manufactured by Tosoh Corporation) and (trade name) Ultrathene 750 (vinyl acetate content: 32%) (manufactured by Tosoh Corporation). The saponified EVA (B) preferably has a melt mass-flow rate of 100 g / 10 min or less, as measured in accordance with JIS K6924-1 (under conditions of 190°C and a load of 2160 g), since this provides a PAS composition that has an excellent balance between melt viscosity and melt tension and is easily suitable for high-speed molding and thin-walled construction. The saponified EVA (B) may be one type alone or two or more types in combination for the purpose of adjusting the amount of hydroxyl groups or the melt viscosity, within the scope of the present invention.

[0020] The amount of saponified EVA (B) is 5 to 45 parts by weight per 100 parts by weight of PAS (A), and preferably 10 to 35 parts by weight, since this provides excellent adhesion to metal surfaces and heat and chemical resistance. If the amount of saponified EVA is less than 5 parts by weight, the resulting resin composition will have poor adhesion to metal surfaces, resulting in gaps when formed into an integrated metal part, making it impossible to ensure insulation. On the other hand, if the amount exceeds 45 parts by weight, the resulting resin composition will have poor heat resistance and oil resistance.

[0021] The high-pressure low-density polyethylene (hereinafter sometimes referred to as LDPE) (C) constituting the PAS composition of the present invention may be any known LDPE. LDPE obtained by a high-pressure process is known as a low-density polyethylene with a long-chain branched structure, high melt tension, and a wide molecular weight distribution. It is recognized as having different physical properties and structure from linear low-density polyethylene (sometimes referred to as LLDPE) obtained by a low-pressure process. Furthermore, for the purpose of adjusting the branching number, melt tension, molecular weight distribution, etc., it may be, for example, a commercially available LDPE prepared by heating and melt-kneading it at 130°C to 220°C in the presence of oxygen using a twin-screw extruder or Banbury mixer, i.e., a heat-melt-treated high-pressure low-density polyethylene. LDPE is characterized by its high melt tension. LDPE prepared by the above-described heat preparation method, in particular, has a high melt tension regardless of the mass flow rate (MFR). It can be prepared, for example, by the methods described in Japanese Patent Nos. 6,047,953 and 6,115,130. In particular, when used as a coating material for insulated wires and the like, the melt tension is improved, and good formability is achieved even under high-speed forming conditions, enabling the formation of a thin, uniform coating material. Therefore, it is preferable that the melt tension at 260°C is 100 mN or more and that the molecular weight distribution (hereinafter, sometimes referred to as Mw) which is the ratio of the weight-average molecular weight (hereinafter, sometimes referred to as Mw) to the number-average molecular weight (hereinafter, sometimes referred to as Mn) is 9.0 or more. In particular, it is preferable that the melt tension is 120 mN or more and that the Mw / Mn is 10.0 or more, in order to obtain a PAS composition with excellent extrusion moldability.

[0022] The melt tensions can be measured by known methods. For example, the melt tensions of the LDPE (C) and PAS composition can be measured in a thermostatic chamber set to 23°C, at a temperature of 260°C, by filling 18 g of sample into a capillary viscometer (manufactured by Toyo Seiki Seisakusho, product name: Capilograph) with a barrel diameter of 9.55 mm and equipped with a die having a length of 8 mm, a diameter of 2.095 mm, and an inlet angle of 90°, setting the piston descending speed to 10 mm / min, and the draw ratio to 4.7, and measuring the load (mN) required for take-up as the melt tension. The Mw, Mn, and Mw / Mn of the LDPE (C) can be measured, for example, using gel permeation chromatography (hereinafter sometimes referred to as GPC). The Mw / Mn of the LDPE (C) in the PAS composition can be determined by heating and dissolving the PAS composition in an aprotic nonpolar solvent such as toluene or xylene and then measuring.

[0023] The blending amount of LDPE (C) is 10 to 45 parts by weight per 100 parts by weight of PAS (A). It is preferably 10 to 35 parts by weight, more preferably 15 to 35 parts by weight, because this results in a PAS composition with an excellent balance between moldability and low dielectric properties. If the blending amount of LDPE is less than 10 parts by weight, the resulting resin composition will have insufficient melt tension and poor extrusion moldability. On the other hand, if the blending amount exceeds 45 parts by weight, problems such as moldability due to excessively high melt tension and the non-stickiness of LDPE that inhibits adhesion of saponified EVA to metal parts are likely to occur.

[0024] The PAS composition of the present invention, which contains PAS (A), saponified EVA (B), and LDPE (C), has a melt viscosity of 2,000 to 8,000 poise, preferably 2,000 to 4,000 poise, since this composition exhibits excellent extrusion moldability for resin piping, coating materials, and the like. If the melt viscosity is less than 2,000 poise, the composition will have a low melt viscosity, resulting in poor extrusion moldability for insulated electric wires, hollow piping, and the like. On the other hand, if the melt viscosity exceeds 8,000 poise, the melt viscosity will be too high, making it difficult to increase the production rate (extrusion rate). The melt viscosity can be measured, for example, using a high-performance flow tester equipped with a die having a diameter of 1 mm and a length of 2 mm, at a measurement temperature of 290°C and a load of 10 kg.

[0025] Furthermore, since the PAS composition has excellent dielectric properties and partial discharge inception voltage, it is preferable that the dielectric constant be 3.2 or less, particularly 3 or less, and even more particularly 2.9 or less, as measured on a 70 mm x 3 mm x 1 mm thick strip test piece at a measurement temperature of 23°C and a measurement frequency of 2 GHz in accordance with JIS C-2565. Furthermore, since the PAS composition has excellent flexibility, it is preferable that the tensile break strain be 8% or more, particularly 10% or more, and even more particularly 15% or more, as measured in accordance with JIS K 7161. Furthermore, since the PAS composition of the present invention enables fine dispersion of the saponified EVA (B) and LDPE (C) in the PAS (A), it is preferable to further blend a modified polyolefin copolymer or polyolefin copolymer having a reactive functional group. By achieving a fine dispersion, the PAS composition has good moldability even under high-speed molding conditions when being made into a coating material, etc., and can mold a thin, uniform coating material. Furthermore, the flexibility of the coating material is increased, and when it is bent into an electric wire or the like, it can conform to the conductor or the like without peeling or cracking.

[0026] The modified polyolefin copolymer having a reactive functional group may be any polyolefin copolymer as long as it belongs to the category. Among them, the PAS composition and insulated wire have excellent flexibility during bending after molding into an electric wire and excellent resistance to cold and heat shock. Therefore, the ethylene-acrylic acid ester copolymer (D１ ), ethylene-methacrylic acid ester copolymer (D ２ ) (hereinafter, sometimes collectively referred to as ethylene-(meth)acrylic acid ester copolymer (D)), which belongs to the category of, for example, reactive functional group-modified ethylene-α,β-unsaturated carboxylic acid alkyl ester copolymers, and examples of the α,β-unsaturated carboxylic acid alkyl ester units constituting the copolymer include methyl acrylate units, ethyl acrylate units, propyl acrylate units, butyl acrylate units, hexyl acrylate units, octyl acrylate units, glycidyl acrylate units, methyl methacrylate units, ethyl methacrylate units, propyl methacrylate units, hexyl methacrylate units, octyl methacrylate units, and glycidyl methacrylate units. Examples of the reactive functional groups include epoxy groups, maleic anhydride groups, carboxylic acid groups, amino groups, and isocyanate groups. The ethylene-(meth)acrylic acid ester copolymer (D) can be used to produce a PAS composition and an insulated wire having particularly excellent impact resistance and flexibility. Examples of reactive functional group-modified ethylene-α,β-unsaturated carboxylic acid alkyl ester copolymers 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, and ethylene-α,β-unsaturated carboxylic acid glycidyl ester-α,β-unsaturated carboxylic acid alkyl ester copolymer.

[0027] Examples of ethylene-(meth)acrylic acid ester copolymers and maleic anhydride-modified ethylene-(meth)acrylic acid ester copolymers include (trade name) Lotader AX8700 and AX8750 manufactured by SK Global Chemical Co., Ltd. and (trade name) Bondfast 7M and 7L manufactured by Sumitomo Chemical Co., Ltd. Examples of maleic anhydride-modified ethylene-(meth)acrylic acid ester copolymers include (trade name) Lotader AX5500, (trade name) BONDINE AX8390, LX4110, and TX8030 manufactured by SK Global Chemical Co., Ltd. The amount of modified polyolefin copolymer or polyolefin copolymer having a reactive functional group to be blended is preferably 15 to 50 parts by weight, and particularly preferably 20 to 40 parts by weight, per 100 parts by weight of PAS, since this enables the production of a coating material or exterior material having an excellent balance between toughness such as impact resistance and heat resistance.

[0028] Furthermore, the PAS composition of the present invention may contain fillers such as fibrous fillers and non-fibrous fillers within the scope of the object of the present invention. Examples of fibrous fillers include glass fibers; whiskers such as silicon nitride whiskers, basic magnesium sulfate whiskers, barium titanate whiskers, potassium titanate whiskers, silicon carbide whiskers, boron whiskers, and zinc oxide whiskers; inorganic fibers such as rock wool, zirconia, alumina silica, barium titanate, silicon carbide, alumina, silica, and blast furnace slag; organic fibers such as wholly aromatic polyamide fibers, phenolic resin fibers, and wholly aromatic polyester fibers; and mineral fibers such as wollastonite and magnesium oxysulfate. Examples of non-fibrous fillers include silicates such as wollastonite, zeolite, sericite, kaolin, mica, pyrophyllite, talc, and alumina silicate; oxides such as aluminum oxide, silicon oxide, magnesium oxide, zirconium oxide, titanium oxide, zinc oxide, and iron oxide; carbonates such as calcium carbonate, magnesium carbonate, and dolomite; sulfates such as calcium sulfate and barium sulfate; nitrides such as silicon nitride, boron nitride, and aluminum nitride; glass flakes, glass beads, etc. The fillers may also be surface-treated with an isocyanate compound, a silane coupling agent, a titanate coupling agent, an epoxy compound, or the like.

[0029] Furthermore, the PAS composition of the present invention may contain a silane coupling agent, since this will result in excellent toughness and the like. Examples of the silane coupling agent include silane coupling agents consisting of a trialkoxysilane coupling agent having a glycidyl group and / or a trialkoxysilane coupling agent having an amino group, and specific examples thereof include 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, and N-2-(aminoethyl)-3-aminopropyltrimethoxysilane.

[0030] Furthermore, the PAS composition of the present invention may contain a release agent to improve the appearance of the molded article. Suitable examples of the release agent include polyethylene wax, polypropylene wax, and fatty acid amide wax. Commonly available commercial products can be used as the polyethylene wax and polypropylene wax. The fatty acid amide wax is a polycondensate of a higher aliphatic monocarboxylic acid, a polybasic acid, and a diamine. Any wax that falls within this category can be used. For example, Light Amide WH-255 (trade name, manufactured by Kyoeisha Chemical Co., Ltd.), which is a polycondensate of stearic acid, sebacic acid, and ethylenediamine, can be used.

[0031] The PAS composition of the present invention may be used by mixing various additives within the scope of the present invention, and may contain one or more conventional additives such as conventionally known plasticizers such as polyalkylene oxide oligomer compounds, thioether compounds, ester compounds, and organic phosphorus compounds; antioxidants; heat stabilizers; ultraviolet inhibitors; and foaming agents. Furthermore, the PAS composition may be used by mixing one or more thermoplastic resins such as various thermosetting resins; thermoplastic elastomers which may have reactive functional groups, epoxy resins, cyanate ester resins, phenolic resins, polyimides, silicone resins, polyesters, polyamides, polyphenylene oxides, polycarbonates, polysulfones, polyetherimides, polyethersulfones, polyetherketones, polyetheretherketones, polyamideimides, and polyalkylene oxides.

[0032] Conventional hot melt kneading methods can be used to produce the PAS composition of the present invention. Examples include hot melt kneading methods using a single-screw or twin-screw extruder, kneader, mill, Brabender, or the like. Melt kneading using a twin-screw extruder is particularly preferred, due to its excellent kneading capacity and productivity. Furthermore, a screw length (L1) to screw diameter (D1) ratio (L1 / D1) of 30 or greater is desirable, as this allows for sufficient kneading of the PAS (A), saponified EVA (B), and LDPE (C), and, in some cases, reaction with other additives, thereby enabling the easy production of a PAS composition with excellent adhesion, adhesion, resistance to thermal cycling, toughness, and melt processability. Furthermore, the cylinder temperature of the kneading zone of the extruder is preferably set to 260 to 330°C, more preferably 260 to 310°C, and particularly preferably 260 to 300°C. Furthermore, the peripheral speed of the screw is preferably 50 to 400 mm / sec, with 150 to 300 mm / sec being particularly preferred. The residence time of the molten resin in the extruder is preferably 30 to 120 seconds, and particularly preferably 30 to 100 seconds.

[0033] The PAS composition of the present invention can be molded into any shape using an extrusion molding machine, blow molding machine, transfer molding machine, compression molding machine, or the like, and can be used to make various products and parts such as electrical and electronic components and automobile parts. In particular, because of its excellent electrical insulation properties, dielectric properties, and adhesion, it can be used to make coating materials for insulated electric wires, insulated hollow pipes for bundling electric wires, and insulated joints. Among these, extrusion molding is preferred when molding into insulated electric wires because of its excellent continuous productivity. Furthermore, injection blow molding, extrusion molding, and blow molding are preferred when making into hollow pipes. Furthermore, because of its excellent electrical insulation properties, dielectric properties, and adhesion, the PAS composition of the present invention is particularly suitable for insulated electric wires used as an insulating coating material on the outer periphery of a conductor. The conductor constituting the insulated electric wire in this case may be any known conductor, and is preferably made of, for example, tough pitch copper, pure copper, a copper alloy, aluminum, or an aluminum alloy.

[0034] The shape of the conductor constituting the insulated wire is not particularly limited. Among them, a rectangular wire having a rectangular cross section is preferred in order to improve the coil occupancy rate of the motor. From the viewpoint of workability when bending the insulated wire into a coil, a rectangular wire having a short side of 0.8 to 5 mm and a long side of 1.4 to 8 mm is preferred. A round wire may also be used, which is advantageous in terms of ease of quality control and cost. Similarly, from the viewpoint of workability when forming a coil, the round wire preferably has a diameter of 0.5 to 5 mm. The insulated wire is formed by coating the conductor with the PAS composition described above as a coating material. The thickness of the coating layer is arbitrary as long as the desired dielectric breakdown strength and partial discharge inception voltage are exhibited. A thickness of 0.05 to 0.3 mm is preferred, as this results in an insulated wire with excellent conformability of the insulating coating layer, dielectric breakdown strength, partial discharge inception voltage, and gas permeation resistance. The molding method for coating the PAS composition can be, for example, using a general molding machine such as an extrusion molding machine, an injection molding machine, a heat compression molding machine, or a transfer molding machine. Among these, wire coating molding using an extruder is preferred because it allows continuous coating of conductors having lengths of several hundred meters to several kilometers and is a molding method excellent in terms of continuous productivity of insulated wires.

[0035] 1A and 1B are cross-sectional views showing examples of insulated wires. Reference numeral 1 in Fig. 1A denotes an insulated wire having a rectangular cross section and an insulating coating material 2 on the outer periphery of a rectangular conductor 2, while reference numeral 4 in Fig. 1B denotes an insulated wire having a round cross section and an insulating coating material 6 on the outer periphery of a round conductor 5. As long as the insulated wire has a coating material made of the PAS composition on the outer periphery of the conductor, it may be a single layer made of the PAS composition or a multilayer including another thermoplastic resin layer, a rubber layer, a thermoplastic elastomer layer, or a thermosetting resin layer. In particular, it may have a water vapor or oxygen barrier layer, a heat-resistant coating layer, or the like. To achieve a high breakdown voltage, a multilayer coating may be used in which an additional layer is added to the PAS composition coating material according to the purpose.

[0036] The insulated wire can be used for general purposes. In particular, when the insulated wire is applied to a motor, a generator, a reactor, or the like, it can improve motor efficiency, output, and power generation efficiency, thereby contributing to energy saving, miniaturization, and weight reduction of electric vehicles and hybrid vehicles.

[0037] The present invention will be described in more detail below with reference to examples, but is not limited to these examples. The PAS (A), saponified EVA (B), polyethylene (C), conductors, etc. used in the examples and comparative examples are shown below.

[0038] <PAS (A)> PPS (A-1): melt viscosity 493 poise. PPS (A-2): melt viscosity 1,120 poise. PPS (A-3): Toray Industries, Inc., (trade name) Torelina M2888, melt viscosity 790 poise.

[0039] <Saponified EVA (B)> Saponified EVA (B-1): manufactured by Tosoh Corporation, trade name Mersen H6960 (vinyl acetate content before saponification treatment: 19 mol%, degree of saponification of vinyl acetate units: 90 wt%, MFR: 40 g / 10 min). Saponified EVA (B-2): manufactured by Tosoh Corporation, trade name Mersen H6051K (vinyl acetate content before saponification treatment: 28 mol%, degree of saponification of vinyl acetate units: 96 wt%, MFR: 7 g / 10 min). Saponified EVA (B-3): manufactured by Tosoh Corporation, trade name Mersen H6410M (vinyl acetate content before saponification treatment: 18 mol%, degree of saponification of vinyl acetate units: 20 wt%, MFR: 15 g / 10 min). Saponified EVA (B-4): Tosoh Corporation, trade name Mersen H6822X (vinyl acetate content before saponification treatment: 6 mol %, degree of saponification of vinyl acetate units: 80 wt %, MFR: 214 g / 10 min).

[0040] <EVA (B')> EVA (B'-5): Ultrathene 751 (trade name), manufactured by Tosoh Corporation (vinyl acetate content 28 mol %, not saponified, MFR 8 g / 10 min).

[0041] <Polyethylene (C)> This was prepared according to the method described in Japanese Patent No. 6047953. A counter-rotating twin-screw extruder (manufactured by Toyo Seiki Seisakusho, trade name: Labo Plastomill 2D25S) with intermeshing screws was used as the kneader, and the melt mass flow rate was 1.6 g / 10 min and the density was 919 kg / m ３ LDPE (manufactured by Tosoh Corporation, (trade name) Petrothene 360; melt tension 75 mN) was melt-kneaded under the conditions of a kneading temperature of 160°C, a discharge rate of 1.7 kg / hour, a screw rotation speed of 60 rpm, an oxygen concentration of 21%, and a filling rate of 80%, and extruded into a strand shape and obtained as LDPE pellets (C-1) using a strand cutter (manufactured by Seiwa Iron Works Co., Ltd.). The screw used was a multi-flight type with reverse leads (2S25R type). The Mw / Mn value was 10.0 and the melt tension was 172 mN. LDPE (C'-2): Commercially available LDPE (manufactured by Tosoh Corporation, (trade name) Petrothene 360; melt tension 75 mN, melt mass-flow rate 1.6 g / 10 min, density 919 kg / m ３The Mw / Mn value was 8.1. LLDPE (C'-3): A commercially available linear low-density polyethylene (LLDPE) (manufactured by Tosoh Corporation, trade name Nipolon-L M50; melt tension 9 mN, melt mass-flow rate 3.0 g / 10 min, density 936 kg / m ３ The Mw / Mn value was 3.5.

[0042] <Ethylene-(meth)acrylic acid ester copolymer (D)> Ethylene-ethyl acrylate-maleic anhydride copolymer (D-1); manufactured by SK global chemical Co., Ltd., (trade name) Bondine AX8390, reactive group: maleic anhydride unit, ethylene unit: α,β-unsaturated carboxylic acid ethyl unit: maleic anhydride unit (weight ratio) = 69.7:29:1.3.

[0043] <Conductor> A rectangular copper wire (manufactured by Tanaka Electric Wire Co., Ltd.) made of tough pitch copper and having a rectangular cross section with a long side of 3.2 mm and a short side of 1.6 mm, and a length of about 500 m or more.

[0044] Synthesis Example 1: In a 50-liter autoclave equipped with a stirrer, Na ２ S・2.9H ２ 6,214 g of 2,214 mcg of 2,214 mcg of 2,214 mcg of 3,5-dichloroaniline and 17,000 g of N-methyl-2-pyrrolidone were charged and gradually heated to 205°C while stirring under a nitrogen stream, and 1,355 g of water was distilled off. After cooling the system to 140°C, 7,168 g of p-dichlorobenzene, 12 g of 3,5-dichloroaniline, and 5,000 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 2 hours, then heated to 250°C over 30 minutes, and further polymerized at 250°C for 3 hours. After polymerization was completed, the system was cooled to room temperature, and the solids were isolated using a centrifuge. The solids were washed with hot water at 180°C and dried overnight at 100°C to obtain poly(p-phenylene sulfide). The resulting poly(p-phenylene sulfide) was dried at 240°C for 4 hours under reduced pressure using a vacuum dryer to obtain PPS (A-1), a linear amino group-containing poly(p-phenylene sulfide) having an amino group content of 0.1 mol% relative to the phenyl groups. The melt viscosity of PPS (A-1) was 493 poise.

[0045] Synthesis Example 2: In a 50-liter autoclave equipped with a stirrer, flaky sodium sulfide (Na ２ S・2.9H ２ 6,214 g of 3,5-dichloroaniline and 17,000 g of N-methyl-2-pyrrolidone were charged and gradually heated to 205°C while stirring under a nitrogen stream, and 1,355 g of water was distilled off. After cooling the system to 140°C, 7,278 g of p-dichlorobenzene, 11.7 g of 3,5-dichloroaniline, and 5,000 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 2 hours, then heated to 250°C over 30 minutes, and polymerized at 250°C for an additional 3 hours. After polymerization was completed, the system was cooled to room temperature and the polymer was isolated using a centrifuge. The solids were repeatedly washed with warm water and dried overnight at 100°C to obtain amino-substituted poly(p-phenylene sulfide) with a melt viscosity of 400 poise. The dried amino group-substituted poly(p-phenylene sulfide) was then loaded into a batch rotary kiln-type baking apparatus and subjected to a curing treatment in an air atmosphere at 240°C for 2 hours, thereby obtaining PPS (A-2) with a melt viscosity of 1,120 poise and an amino group content of 0.1 mol% relative to the phenyl groups. The PAS compositions, insulated wires, etc. obtained in the examples and comparative examples were evaluated and measured by the methods shown below.

[0046] (1) Evaluation of Adhesion of PAS Composition Pellets of a PAS composition that had been dried in advance were placed in the hopper of an in-line screw-type electric injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., (product name) SE-75S), and a flat plate (length 70 mm × width 70 mm × thickness 1.0 mm) was obtained under conditions of a cylinder temperature of 290°C and a mold temperature of 80°C. Next, a separately prepared copper sheet (145 mm long x 145 mm wide x 0.1 mm thick, made of pure copper) was placed on a mold frame for hot compression molding (external dimensions: 200 mm long x 200 mm wide x 0.8 mm thick, internal dimensions: 150 mm long x 150 mm wide punched frame). Two injection-molded flat plates of the PAS composition were stacked and set, and a release film (made of polyimide) was added. A hydraulic press (manufactured by Shinto Kogyo Co., Ltd., 50t automatic press) was used to hot compress and press mold the copper and PAS composition to obtain a laminated flat plate (150 mm long x 150 mm wide x 0.7 mm thick). The laminated flat plate was cut to a width of 15 mm, and the four central points were used as test pieces for adhesion evaluation.

[0047] (Adhesion Measurement) Using a tensile tester (Tensilon RTE-1210 (trade name) manufactured by ORIENTEC), the strength when peeling the copper sheet from the PAS layer at 20 mm / sec was measured, and the average value of four tests was taken as the adhesion (unit: N / 15 mm). In this case, a value of 8.0 N / 15 mm or more was determined to be excellent in adhesion.

[0048] (2) Measurement of Relative Dielectric Constant Test pieces for measuring relative dielectric constant (70 mm x 3 mm x 1 mm thick) were prepared by cutting from the injection-molded flat plates obtained by the same method as in (1) above. The relative dielectric constant and dielectric loss tangent of these test pieces were measured at a measurement frequency of 2 GHz in accordance with JIS C-2565 using a relative dielectric constant measuring device (manufactured by AET Corporation, (product name) Cavity Resonator). In this case, materials with a relative dielectric constant of 3.0 or less were considered to have a certain partial discharge inception voltage, and those with a relative dielectric constant of 2.9 or less were considered to be excellent.

[0049] (3) Measurement of Tensile Properties Test pieces for evaluating tensile properties (tensile strength, tensile modulus, tensile breaking strain) were prepared by injection molding using an injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., product name: SE75S) heated to a cylinder temperature of 310°C and a mold temperature of 60°C, from a pre-dried PAS composition. Here, the bending property test was performed in accordance with JIS K7171. In this case, PAS compositions with a tensile breaking strain of 10% or more were considered to have good flexibility, and those with a tensile breaking strain of 15% or more were considered to be excellent.

[0050] (4) Melt Viscosity Measurement The melt viscosity was measured using a high-temperature flow tester (manufactured by Shimadzu Corporation, product name CFT-500) equipped with a die having a diameter of 1 mm and a length of 2 mm, under the conditions of a measurement temperature of 290°C and a load of 10 kg. At this time, for PAS compositions, those having a melt viscosity of 2,000 poise or more and 8,000 poise or less were determined to have good extrusion moldability.

[0051] (5) Melt tension measurement The melt tension was measured by a known method. In a thermostatic chamber set to 23°C, the temperature was set to 260°C, and 18 g of a sample was filled into a capillary viscometer (manufactured by Toyo Seiki Seisaku-sho, Ltd., under the trade name of Capilograph) having a barrel diameter of 9.55 mm and equipped with a die having a length of 8 mm, a diameter of 2.095 mm, and an inlet angle of 90°. The piston descending speed was set to 10 mm / min, and the draw ratio was set to 4.7, and the load (mN) required for take-up was measured as the melt tension.

[0052] (6) Measurement of Mw and Mn The Mw, Mn, and Mw / Mn of LDPE were measured using the GPC method. A measurement sample was weighed, added to a solvent of HPLC-grade 1,2,4-trichlorobenzene (manufactured by Wako Pure Chemical Industries, Ltd.) containing 0.1% BHT (manufactured by Wako Pure Chemical Industries, Ltd.) as an antioxidant, and dissolved by shaking at 140°C for 1 hour to prepare a sample solution. The measurement apparatus used was a Tosoh Corporation (trade name) HLC-8121GPC / HT, and the separation columns used were three connected TSKgel GMHHR-H(20)HT (manufactured by Tosoh Corporation, inner diameter 7.8 mm, length 30 cm). The mobile phase was HPLC-grade 1,2,4-trichlorobenzene (Wako Pure Chemical Industries, Ltd.) with 0.05% BHT (Wako Pure Chemical Industries, Ltd.) added as an antioxidant, and was moved through a separation column maintained at 140°C at a flow rate of 1.0 ml / min. 0.3 ml of a sample solution adjusted to a concentration of 1.0 mg / ml was injected into the mobile phase, and the separated sample components were detected using a differential refractometer. A quintic approximation curve created using standard polystyrene (Tosoh Corporation) was used as a calibration curve to calculate Mn, Mw, and Mw / Mn.

[0053] (7) Evaluation of PAS Compositions Those excellent in adhesion, relative dielectric constant, flexibility and extrusion moldability were evaluated as "◯" (good), and those inferior in any one of these were evaluated as "×" (bad).

[0054] (8) Cross-sectional observation of insulated wire The obtained insulated wire was cut to a length of 1 cm, embedded in colored phenolic resin, and polished with waterproof abrasive paper (#240 to #2000) so that the cross-section could be observed, followed by a mirror finish with buffing (#8000) to create a sample for cross-sectional observation. The film thickness on all four sides of this sample was measured using an optical microscope at approximately 3,000 magnification, and the average value was taken as the film thickness. The interface between the copper and the coating material was observed, and the maximum value of the gap on all four sides was taken as the "gap (μm)."

[0055] (9) Evaluation of bending workability of insulated wires Using a 5 mm diameter half-moon-shaped bending jig (made of carbon steel), the insulated wires were bent at an angle of 180 degrees relative to the short side, and the appearance of the insulating coating after bending was observed visually or with a magnifying glass. Five tests were conducted, and specimens in which the appearance of the insulating coating after bending was good in all specimens were rated as "good." In contrast, specimens in which one or more cracks occurred in the insulating coating outside the arc of the wire after bending were rated as "cracked."

[0056] (10) Judgment of insulated wires If there was no gap between the coating material and the conductor in the cross section of the insulated wire and no cracks occurred in the bending workability evaluation of the insulated wire, it was judged to be suitable as a wire for a motor or generator and given a rating of "○" (good). If either of the criteria was not met, it was judged to be unsuitable as a wire and given a rating of "×" (bad).

[0057] Example 1 100 parts by weight of the PPS (A-1) obtained in Synthesis Example 1, 8 parts by weight of saponified EVA (B-1), and 30 parts by weight of LDPE (C-1) were uniformly mixed in advance and charged into the hopper of a twin-screw extruder (manufactured by The Japan Steel Works, Ltd., (trade name) TEX-25αIII, L1 / D1 = 55) having three kneading zones. The mixture was melt-kneaded at a raw material supply rate of 12 kg / h and a screw rotation speed of 250 rpm (circumferential speed 327 mm / sec) under conditions where the cylinder temperature of the kneading zone was heated to 270°C. The molten PAS composition flowing out of the die after a residence time of 50 seconds was cooled and then cut to prepare a pellet-shaped PAS composition. The obtained PAS composition was measured and evaluated by the above-mentioned methods, and the results are shown in Table 1.

[0058] Examples 2 to 10 Pellets of PAS compositions were prepared in the same manner as in Example 1, except that the blending amounts of PAS (A), saponified EVA (B), and polyethylene (C) were set to the conditions shown in Table 1. Each physical property was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0059]

[0060] Comparative Examples 1 to 6 Pellet-shaped resin compositions were prepared in the same manner as in Example 1, except that the blending amounts of PAS (A), saponified EVA (B), EVA (B'), polyethylene (C), and polyethylene (C') were set to the conditions shown in Table 2. Each physical property was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[0061]

[0062] Example 11 100 parts by weight of the PPS (A-2) obtained in Synthesis Example 2, 8 parts by weight of saponified EVA (B-1), and 30 parts by weight of LDPE (C-1) were uniformly mixed in advance and charged into the hopper of a twin-screw extruder having three kneading zones (manufactured by The Japan Steel Works, Ltd., (trade name) TEX-25αIII, cylinder diameter 25 mm, L1 / D1 = 55). The mixture was melt-kneaded under conditions where the cylinder temperature of the kneading zone was heated to 290°C, the raw material supply rate was 12 kg / h, and the screw rotation speed was 250 rpm (circumferential speed 327 mm / sec). The molten composition flowed out of the die after a residence time of approximately 60 seconds. The molten composition was water-cooled, cut with a rotary cutter, and then dried in a constant temperature bath at 80°C for approximately 3 hours to prepare pellets of a PPS composition.

[0063] The resulting pelletized PPS composition was placed in the hopper of a horizontal single-screw extruder (cylinder diameter 20 mm, cylinder length 500 mm; full-flight screw: compression ratio 3.2) and pressure-fed to the crosshead of a wire coating molding machine at a cylinder temperature of 290°C and a die temperature of 290°C. A rectangular tough-pitch copper wire (long side 3.2 mm, short side 1.6 mm, manufactured by Tanaka Electric Wire Co., Ltd.) was placed in a heating furnace under a nitrogen atmosphere, and the conductor preheated to approximately 180°C was introduced into the crosshead of a wire coating molding machine. The coating material was coated to a thickness of 130±10 μm and molded at a molding speed of 2 m / min to produce an insulated wire. The wire was cooled to 60°C or below at room temperature and cut at approximately 50 cm intervals to obtain an insulated wire for evaluation. The evaluation results of the insulated wires are shown in Table 3.

[0064] Examples 12 to 19 Pellets of PPS compositions and insulated wires were obtained in the same manner as in Example 10, except that the blending amounts of the PAS resin (A), the saponified EVA (B), the polyethylene (C), and the ethylene-(meth)acrylic acid ester copolymer (D) were changed to the amounts shown in Table 3, and the evaluation results are shown in Table 3.

[0065]

[0066] Comparative Examples 7 to 12 Pellet-shaped resin compositions and insulated wires were obtained in the same manner as in Example 10, except that the amounts of PAS resin (A), saponified EVA (B), EVA (B'), and polyethylene (C, C') were changed to the amounts shown in Table 4. The evaluation results are shown in Table 4.

[0067]

[0068] In addition, the claims, specifications, drawings and abstracts of Japanese Patent Application Nos. 2024-062712 and 2024-062713 filed on April 9, 2024, and Japanese Patent Application No. 2025-008608 filed on January 21, 2025 are all cited herein and incorporated by reference as the disclosure of the specification of the present invention.

[0069] The PAS composition of the present invention has a low dielectric constant and adhesion to conductors without impairing the heat resistance, dielectric breakdown strength, etc., inherent to PAS, and therefore can be suitably used for applications such as electric / electronic parts or automobile parts, particularly for applications such as hollow molded products such as coating materials for insulated electric wires, inverter bus bars, and insulating piping parts and joints. Motors, generators, or reactors using these can improve motor efficiency and power generation efficiency, thereby contributing to energy conservation and miniaturization and weight reduction of electric vehicles and hybrid vehicles.

[0070] 1: Insulated wire with rectangular cross section 2: Conductor 3: Insulating coating material 4: Insulated wire with round cross section 5: Conductor 6: Insulating coating material

Claims

1. A polyarylene sulfide composition comprising 100 parts by weight of polyarylene sulfide (A), 5 to 45 parts by weight of saponified ethylene-vinyl acetate copolymer (B), and 10 to 45 parts by weight of high-pressure low-density polyethylene (C), and having a melt viscosity of 2,000 to 8,000 poise at 290°C under a load of 10 kg.

2. The polyarylene sulfide composition according to claim 1, wherein the saponified ethylene-vinyl acetate copolymer (B) is a saponified ethylene-vinyl acetate copolymer having a degree of saponification of vinyl acetate units calculated in accordance with JIS K7192 of 60% by weight or more.

3. The polyarylene sulfide composition according to claim 1 or 2, characterized in that the saponified ethylene-vinyl acetate copolymer (B) is a saponified ethylene-vinyl acetate copolymer having an ethylene unit content of 65 mol% or more and 90 mol% or less.

4. A polyarylene sulfide composition according to any one of claims 1 to 3, characterized in that the high-pressure low-density polyethylene (C) is a high-pressure low-density polyethylene having a melt tension of 100 mN or more at 260°C and a molecular weight distribution determined by gel permeation chromatography of 9.0 or more.

5. The polyarylene sulfide composition according to any one of claims 1 to 4, wherein the high-pressure low-density polyethylene (C) is a heat-melt-treated high-pressure low-density polyethylene.

6. The polyarylene sulfide composition according to any one of claims 1 to 5, further comprising an ethylene-(meth)acrylic acid ester copolymer (D).

7. An insulating coating material, which is an extrusion molded product of the polyarylene sulfide composition according to any one of claims 1 to 6.

8. A resin pipe which is an extrusion molded product of the polyarylene sulfide composition according to any one of claims 1 to 6.

9. An insulated wire comprising a conductor and the insulating covering material according to claim 7 around the conductor.

10. The insulated wire according to claim 9, wherein the insulating covering material is a single layer having a thickness of 0.05 to 0.3 mm.

11. An insulated wire according to claim 10, characterized in that the conductor is made of tough pitch copper and / or pure copper and has a rectangular cross section with short sides of 0.8 to 5 mm and long sides of 1.4 to 8 mm.

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