Resin composition and molded article

Abstract

To provide a polyamide / polyphenylene ether resin composition excellent in fluidity, heat resistance and surface impact strength and also excellent in repeated processability and to provide a molded article comprising the resin composition.SOLUTION: There is provided a resin composition which comprises (a) a polyamide, (b) a polyphenylene ether, (c) a compatibilizer of the polyamide (a) and the polyphenylene ether (b) and (d) a polyhydric alcohol having two or more hydroxyl groups and a number average molecular weight (Mn) of less than 500, wherein the content of the polyhydric alcohol (d) is 0.3 to 5 pts.mass based on the total 100 pts.mass of the polyamide (a) and the polyphenylene ether (b), the ratio (the terminal amino group concentration / the terminal carboxyl group concentration) of the terminal amino group concentration of the polyamide (a) to the terminal carboxyl group concentration is 0.3 to 0.5 and the polyamide (a) forms a continuous phase.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition and a molded article. [Background technology]

[0002] Polyphenylene ether has excellent mechanical properties, electrical properties, and heat resistance, and also has excellent dimensional stability, and is therefore widely used, but when used alone, it has poor moldability.

[0003] To improve this, a technique of blending polyamide was proposed in Patent Document 1 and elsewhere, and currently, various improvements have been made to this polymer alloy, which is used in a variety of applications as a metal substitute for electrical and electronic components, automotive parts, etc.

[0004] Meanwhile, polyamides have traditionally been used in a wide range of fields, including automotive parts, machine parts, and electrical and electronic parts, due to their excellent mechanical strength, heat resistance, chemical resistance, etc. Among these, polyamide 6,6 has traditionally been used for relay blocks installed in the engine compartment of automobiles, but this has had the problem of significant dimensional change when it absorbs water.

[0005] For this reason, they have recently been gradually replaced by polyamide / polyphenylene ether resin compositions. Patent Document 2 discloses a technique for controlling the polyphenylene ether and vinyl aromatic-olefin block copolymer in a composition consisting of polyphenylene ether, polyamide, and vinyl aromatic-olefin block copolymer to a specific dispersion size. Patent Document 3 also discloses a composition containing polyphenylene ether, polyamide, and a water-soluble substance having a specific water solubility. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 45-997 [Patent Document 2] Japanese Patent Application Laid-Open No. 1-79258 [Patent Document 3] Japanese Patent Application Laid-Open No. 2005-231219 [Summary of the Invention] [Problems to be Solved by the Invention]

[0007] Automobile parts, machine parts, electrical and electronic parts, etc. tend to have more complex shapes, and furthermore, there is a current trend towards miniaturization and thinning. Among them, SMT-compatible parts typified by recent relay blocks and connectors, in particular, have increasingly complex, miniaturized, and thinned shapes. Also, from the perspective of resource sustainability, there is a growing demand for designs that allow the reuse of materials. Therefore, materials are required to have fluidity, heat resistance, surface impact strength, and repeat processability during injection molding. However, none of the technologies proposed in Patent Documents 1 to 3 were sufficient to provide a material that retains excellent moldability for thin-walled parts while simultaneously being excellent in heat resistance, surface impact strength, and repeat processability.

[0008] Therefore, an object of the present invention is to provide a polyamide / polyphenylene ether resin composition that is excellent in fluidity, heat resistance, and surface impact strength, and also excellent in repeat processability, and a molded article containing the resin composition. [Means for Solving the Problems]

[0009] As a result of intensive studies to solve the above problems, the present inventors have found that by adding a compatibilizer for polyamide and polyphenylene ether and a specific polyhydric alcohol to a polyamide / polyphenylene ether resin composition using a specific polyamide, the above problems can be solved, and the present invention has been achieved.

[0010] That is, the present invention is as follows. [1] (a) Polyamide, (b) Polyphenylene ether, (c) a compatibilizer for the (a) polyamide and the (b) polyphenylene ether 、 ( d) Polyhydric alcohols having two or more hydroxyl groups and a number average molecular weight (Mn) of less than 500 and (e) As an impact improver, a block copolymer containing at least one block mainly composed of an aromatic vinyl monomer unit and at least one block mainly composed of a conjugated diene monomer unit and / or a hydrogenated product of the block copolymer Including, the content of the (d) polyhydric alcohol is 0.3 to 5 parts by mass relative to 100 parts by mass of the total amount of the (a) polyamide and the (b) polyphenylene ether, the ratio of the terminal amino group concentration to the terminal carboxyl group concentration of the (a) polyamide (terminal amino group concentration / terminal carboxyl group concentration) is 0.3 to 0.5; A resin composition, characterized in that the (a) polyamide forms a continuous phase. [2] The resin composition according to [1], wherein the content of the (a) polyamide is 40 to 90 parts by mass and the content of the (b) polyphenylene ether is 10 to 60 parts by mass, relative to 100 parts by mass of the total amount of the (a) polyamide and the (b) polyphenylene ether. [3] The resin composition according to [1] or [2], wherein the (a) polyamide has a formic acid relative viscosity (VR) of 30 to 40. [4] The resin composition according to any one of [1] to [3], wherein the (a) polyamide is polyamide 6,6. [5] The resin composition according to any one of [1] to [4], wherein the polyhydric alcohol (d) is dipentaerythritol. [6 ] [ 1]~[ 5 10. A molded article comprising the resin composition according to claim 10. [ 7 ] Automotive electrical and electronic parts, 6 ] A molded product described in. [Effects of the Invention]

[0011] According to the present invention, a polyamide / polyphenylene ether resin composition excellent in fluidity, heat resistance, and surface impact strength, and capable of maintaining excellent fluidity and surface impact strength even after repeated extrusion, and a molded article containing the resin composition can be obtained.

Mode for Carrying Out the Invention

[0012] Hereinafter, the content of the present invention will be described in detail.

[0013] [Resin Composition] The resin composition of the present embodiment contains (a) a polyamide, (b) a polyphenylene ether, (c) a compatibilizer for the (a) polyamide and the (b) polyphenylene ether, and (d) one or more polyhydric alcohols having two or more hydroxyl groups and a number average molecular weight (Mn) of less than 500. The content of the (d) polyhydric alcohol is 0.3 to 5 parts by mass with respect to 100 parts by mass of the total amount of the (a) polyamide and the (b) polyphenylene ether. The ratio (terminal amino group concentration / terminal carboxyl group concentration) of the terminal amino group concentration of the (a) polyamide to the terminal carboxyl group concentration is 0.3 to 0.5, and the (a) polyamide forms a continuous phase. By adopting the above configuration, the resin composition of the present embodiment can, for example, suppress the bleed-out phenomenon when formed into an injection molded article, and at the same time, can be a resin composition excellent in fluidity, heat resistance, and surface impact strength. Further, the resin composition of the present embodiment can exhibit the retention of fluidity and surface impact strength even when used repeatedly.

[0014] [(a) Polyamide] The (a) polyamide of the present embodiment (hereinafter, may be simply referred to as the "(a) component") is not particularly limited as long as it has an amide bond {-NH-C(=O)-} in the repeating unit of the polymer main chain.

[0015] Generally, polyamides can be obtained by ring-opening polymerization of lactams, polycondensation of diamines and dicarboxylic acids, polycondensation of ω-aminocarboxylic acids, etc., but are not limited to the resins obtained by these methods.

[0016] Specific examples of lactams include ε-caprolactam, enanthlactam, ω-laurolactam, etc.

[0017] The above diamines can be roughly classified into aliphatic, alicyclic and aromatic diamines. Specific examples of diamines include tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, tridecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, 1,9-nonanediamine, 2-methyl-1,8-octanediamine, ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,12-dodecanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 5-methyl-1,9-nonanediamine and other aliphatic diamines; 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, m-phenylenediamine, p-phenylenediamine, m-xylylenediamine, p-xylylenediamine, etc. The dicarboxylic acids can be roughly classified into aliphatic, alicyclic and aromatic dicarboxylic acids. Specific examples of dicarboxylic acids include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, 1,1,3-tridecanedioic acid, 1,3-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, dimer acid, etc.

[0018] As the aminocarboxylic acid, specifically, ε-aminocaproic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 9-aminononanoic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, 13-aminotridecanoic acid, etc. can be mentioned.

[0019] In this embodiment, any of the copolyamide polyamides obtained by polycondensing these lactams, diamines, dicarboxylic acids, and ω-aminocarboxylic acids alone or as a mixture of two or more can be used.

[0020] Also, those obtained by polymerizing these lactams, diamines, dicarboxylic acids, and ω-aminocarboxylic acids to the stage of low molecular weight oligomers in a polymerization reactor and then increasing the molecular weight with an extruder or the like can also be preferably used.

[0021] Particularly, as the (a) polyamide that can be preferably used in this embodiment, polyamide 6, polyamide 6,6, polyamide 4,6, polyamide 11, polyamide 12, polyamide 6,10, polyamide 6,12, polyamide 6 / 6,6, polyamide 6 / 6,12, polyamide MXD (m-xylylenediamine),6, polyamide 6,T, polyamide 9,T, polyamide 6,I, polyamide 6 / 6,T, polyamide 6 / 6,I, polyamide 6,6 / 6,T, polyamide 6,6 / 6,I, polyamide 6 / 6,T / 6,I, polyamide 6,6 / 6,T / 6,I, polyamide 6 / 12 / 6,T, polyamide 6,6 / 12 / 6,T, polyamide 6 / 12 / 6,I, polyamide 6,6 / 12 / 6,I, etc. can be mentioned. Among these, polyamides obtained by copolymerizing a plurality of polyamides with an extruder or the like can also be used. Among them, preferred polyamides are one or more selected from polyamide 6, polyamide 6,6, polyamide 4,6, polyamide 11, polyamide 12 of aliphatic polyamides; and polyamide 9,T, polyamide 6 / 6,T, polyamide 6,6 / 6,T, polyamide 6,6 / 6,I, polyamide MXD,6 of semi-aromatic polyamides, and more preferably one or more polyamides selected from polyamide 6,6, polyamide 6, polyamide 9,T, polyamide 6,6 / 6,I.

[0022] In this embodiment, the formic acid relative viscosity (VR) can be used as an index of the molecular weight of the (a) polyamide. The formic acid relative viscosity (VR) is the relative viscosity of a formic acid solution of the (a) polyamide, and is a relative viscosity obtained by comparing the viscosity of the formic acid solution of the (a) polyamide with the viscosity of formic acid itself. The higher the VR value, the higher the molecular weight is evaluated to be. The VR is measured in accordance with ASTM-D 789. Specifically, the VR value can be determined by measuring at 25°C a solution prepared by dissolving (a) polyamide in 90% by mass formic acid (10% by mass water) to a concentration of 8.4% by mass. The VR of the (a) polyamide is preferably 25 or more and 45 or less, more preferably 25 or more and 40 or less, and even more preferably 30 or more and 40 or less. When the VR of the (a) polyamide is 25 or more, the mechanical properties tend to be better. On the other hand, when the VR of the (a) polyamide is 45 or less, the flowability tends to be better while maintaining the mechanical properties, and the molding processability tends to be better.

[0023] The (a) polyamide of this embodiment may be a mixture of multiple polyamides with different VRs.

[0024] (a) The terminal groups of polyamides are involved in the reaction with (b) polyphenylene ether. Generally, polyamides have amino or carboxyl groups as terminal groups. Generally, as the concentration of terminal carboxyl groups increases, impact resistance decreases and fluidity improves. Conversely, as the concentration of terminal amino groups increases, impact resistance improves and fluidity decreases. In the present embodiment, the ratio of the terminal amino group concentration to the terminal carboxyl group concentration of (a) polyamide (terminal amino group concentration / terminal carboxyl group concentration) is 0.3 to 0.5, preferably 0.3 to 0.45, and more preferably 0.3 to 0.4. By setting it within this range, the flowability and impact resistance of the composition, as well as the flowability and dart impact strength during repeated extrusion, can be improved.

[0025] In addition, the terminal amino group concentration of the (a) polyamide in this embodiment is preferably 20 to 80 μmol / g, more preferably 20 to 60 μmol / g, and even more preferably 20 to 50 μmol / g. By setting the terminal amino group concentration within the above range, the fluidity and impact resistance of the composition, as well as the fluidity and surface impact strength during repeated extrusion, can be improved more favorably. In addition, the terminal carboxyl group concentration of the (a) polyamide in this embodiment is preferably 40 to 150 μmol / g, more preferably 60 to 120 μmol / g, and even more preferably 70 to 110 μmol / g. By setting the terminal carboxyl group concentration within the above range, the fluidity and impact resistance of the composition, as well as the fluidity and surface impact strength during repeated extrusion, can be improved more favorably.

[0026] Known methods can be used to adjust these terminal groups of the (a) polyamide. For example, a method of adding one or more selected from diamine compounds, monoamine compounds, dicarboxylic acid compounds, monocarboxylic acid compounds, etc. so as to achieve a predetermined terminal concentration during the polymerization of the (a) polyamide can be mentioned.

[0027] The concentrations of the terminal amino group and the terminal carboxyl group referred to in this embodiment can be measured by various methods. 1 In terms of accuracy and simplicity, it is preferable to determine it from the integral value of the characteristic signal corresponding to each terminal group by 1H-NMR. For example, as a specific method for quantifying the terminal group concentration of semi-aromatic polyamide, it is recommended to follow the method described in the examples of JP-A-7-228689.

[0028] When a semi-aromatic polyamide is used as the (a) polyamide of this embodiment, it is preferable that 10 to 95% of the terminal groups of its molecular chain are blocked with a terminal blocking agent. The lower limit of the percentage of molecular chain terminal groups blocked with a terminal blocking agent (terminal blocking rate) is more preferably 40%, and even more preferably 60%. By setting the terminal blocking rate to 10% or more, it is possible to reduce viscosity changes during melt molding of the resin composition of this embodiment, and the resulting molded article tends to have excellent physical properties such as appearance and heat resistance during processing. Furthermore, the upper limit of the terminal blocking rate is more preferably 90%. By setting the terminal blocking rate to 95% or less, it tends to have excellent effects such as excellent impact resistance of the composition and excellent surface appearance of the molded article.

[0029] The terminal blocking rate of the semi-aromatic polyamide as the (a) polyamide of this embodiment can be calculated by measuring the number of terminal carboxyl groups, terminal amino groups, and terminal groups blocked with a terminal blocking agent present in the polyamide resin, and according to the following formula (1): End sealing rate (%)=[(α-β) / α]×100...(1) (wherein α represents the total number of terminal groups in the molecular chain (unit = mole; this is usually equal to twice the number of polyamide molecules), and β represents the total number of carboxyl and amino terminal groups remaining uncapped.)

[0030] The end-capping agent is not particularly limited as long as it is a monofunctional compound reactive with the amino or carboxyl group at the end of the polyamide, but monocarboxylic acids or monoamines are preferred from the viewpoints of reactivity and stability of the blocked end, and monocarboxylic acids are more preferred from the viewpoints of ease of handling, etc. Other usable end-capping agents include acid anhydrides, monoisocyanates, monoacid halides, monoesters, and monoalcohols.

[0031] The monocarboxylic acids used as terminal blocking agents are not particularly limited as long as they have reactivity with amino groups. Examples include aliphatic monocarboxylic acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutyric acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; aromatic monocarboxylic acids such as benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid; and any mixtures thereof. Among these, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, and benzoic acid are preferred from the viewpoints of reactivity, stability of the blocked terminal, price, etc., and acetic acid and benzoic acid are particularly preferred.

[0032] The monoamines used as terminal blocking agents are not particularly limited as long as they have reactivity with carboxyl groups. Examples include aliphatic monoamines such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine; alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine, and naphthylamine; and any mixtures thereof. Among these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are preferred from the viewpoints of reactivity, boiling point, stability of the blocked terminal, price, etc., and butylamine, hexylamine, and octylamine are particularly preferred.

[0033] Further, in the present embodiment, for the purpose of further improving the heat stability imparted to the resin composition by the polyamide, transition metals excluding iron and / or halogens may be present in the resin composition.

[0034] There is no particular limitation on the type of transition metal, but copper, cerium, nickel, and cobalt are preferred, with copper being particularly preferred. Among the halogens, bromine and iodine are preferred.

[0035] The amount of transition metals other than iron, when the total amount of the resin composition is taken as 100 mass%, is preferably 1 mass ppm or more and less than 200 mass ppm, more preferably 5 mass ppm or more and less than 100 mass ppm, and similarly, the amount of halogens is preferably 500 mass ppm or more and less than 1500 mass ppm, more preferably 700 mass ppm or more and less than 1200 mass ppm.

[0036] The method for adding these transition metals and / or halogens to the resin composition is not particularly limited, and examples thereof include a method of adding them as a powder when the polyamide / polyphenylene ether resin composition is melt-kneaded, a method of adding them during polyamide polymerization, a method of preparing master pellets by adding them to the polyamide at a high concentration, and then adding these master pellets to the resin composition, but any of these methods may be used. Among these methods, the preferred methods are the method of adding them during polyamide polymerization, or the method of preparing master pellets by adding them to the polyamide at a high concentration, and then adding them.

[0037] In addition to the above-mentioned transition metals and / or halogens, known organic stabilizers can also be used without any problems in this embodiment. Examples of organic stabilizers include hindered phenol-based antioxidants such as Irganox 1098 (manufactured by Ciba Specialty Chemicals Co., Ltd.), phosphorus-based processing heat stabilizers such as Irgafos 168 (manufactured by Ciba Specialty Chemicals Co., Ltd.), lactone-based processing heat stabilizers such as HP-136 (manufactured by Ciba Specialty Chemicals Co., Ltd.), sulfur-based heat stabilizers, hindered amine-based light stabilizers, etc. Among these organic stabilizers, hindered phenol-based antioxidants, phosphorus-based processing heat stabilizers, or a combination thereof are more preferred. The preferred blending amount of these organic stabilizers is 0.001 to 1 part by mass per 100 parts by mass of (a) polyamide.

[0038] [(b) Polyphenylene ether] Specific examples of the (b) polyphenylene ether (hereinafter, sometimes simply referred to as "component (b)") in this embodiment include poly(2,6-dimethyl-1,4-phenylene ether), poly(2-methyl-6-ethyl-1,4-phenylene ether), poly(2-methyl-6-phenyl-1,4-phenylene ether), poly(2,6-dichloro-1,4-phenylene ether), and the like, as well as polyphenylene ether copolymers such as copolymers of 2,6-dimethylphenol with other phenols (for example, copolymers with 2,3,6-trimethylphenol and copolymers with 2-methyl-6-butylphenol as described in JP-B-52-17880). Among these, particularly preferred polyphenylene ethers are poly(2,6-dimethyl-1,4-phenylene ether), a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol, or a mixture thereof.

[0039] (b) The method for producing polyphenylene ether is not particularly limited as long as it is a known method, and examples thereof include the method described in U.S. Pat. No. 3,306,874, in which a complex of a cuprous salt and an amine is used as a catalyst to oxidatively polymerize 2,6-xylenol, and the production methods described in U.S. Pat. Nos. 3,306,875, 3,257,357, and 3,257,358, JP-A-50-51197, JP-B-52-17880, and JP-B-63-152628, etc.

[0040] The reduced viscosity of the (b) polyphenylene ether in this embodiment (measured using a 0.5 g / dL chloroform solution at 30°C using an Ubbelohde viscometer) is preferably in the range of 0.30 to 0.80 dL / g, more preferably 0.35 to 0.75 dL / g, and most preferably 0.38 to 0.55 dL / g. When the (b) polyphenylene ether has a reduced viscosity in this range, it is preferred because it has excellent properties such as impact resistance and heat resistance. In the polyphenylene ether (b) of this embodiment, a blend of two or more polyphenylene ethers having different reduced viscosities can also be preferably used.

[0041] In addition, various known stabilizers can be suitably used to stabilize the (b) polyphenylene ether. Examples of stabilizers include metal-based stabilizers such as zinc oxide and zinc sulfide, and organic stabilizers such as hindered phenol-based stabilizers, phosphorus-based stabilizers, and hindered amine-based stabilizers. The preferred amount of these stabilizers is less than 5 parts by mass per 100 parts by mass of the (b) polyphenylene ether.

[0042] Furthermore, known additives that can be added to (b) polyphenylene ether may be added in an amount of less than 10 parts by mass per 100 parts by mass of (b) polyphenylene ether.

[0043] [Amount ratio of (a) polyamide to (b) polyphenylene ether] In this embodiment, the preferred contents of (a) polyamide and (b) polyphenylene ether, when the total amount of both is 100 parts by mass, are within the range of 40 to 90 parts by mass of (a) polyamide and 10 to 60 parts by mass of (b) polyphenylene ether. A more preferred range is 50 to 75 parts by mass of (a) polyamide and 25 to 50 parts by mass of (b) polyphenylene ether, and an even more preferred range is 50 to 70 parts by mass of (a) polyamide and 30 to 50 parts by mass of (b) polyphenylene ether. A content ratio of (a) to (b) within this range is preferred, as it provides an excellent balance of heat resistance, fluidity, and dart impact strength. Incidentally, the content of these in the resin composition can be determined by a calibration curve method using Fourier transform infrared spectroscopy (FT-IR).

[0044] In this embodiment, the total content of (a) polyamide and (b) polyphenylene ether in the resin composition is preferably 50% by mass or more, more preferably 60% by mass or more, and still more preferably 70% by mass or more, with the total resin composition being 100% by mass.

[0045] [Dispersion form of (a) polyamide and (b) polyphenylene ether] In the resin composition of this embodiment, the phase containing (a) polyamide is the continuous phase. On the other hand, the phase containing (b) polyphenylene ether may be the dispersed phase. Incidentally, the formation of the continuous phase by (a) polyamide can be determined by dyeing a test piece obtained by molding the resin composition so that (a) polyamide is dyed and observing it at a magnification of 3000 to 25000 times using a scanning electron microscope (SEM). Specifically, it can be determined by the method described in the examples below.

[0046] [(c) Compatibilizer] The (c) compatibilizer of this embodiment (hereinafter, may be simply referred to as the “(c) component”) refers to a polyfunctional compound that interacts with (b) polyphenylene ether, (a) polyamide, or both of them. This interaction may be chemical (e.g., grafting) or physical (e.g., change in the surface characteristics of the dispersed phase). In any case, the resulting polyamide-polyphenylene ether mixture exhibits improved compatibility.

[0047] Examples of compatibilizers that can be used in this embodiment are described in detail in JP-A-8-48869 and JP-A-9-124926, etc. All of these known compatibilizers can be used, and combined use is also possible. Among these various compatibilizers, examples of particularly preferred compatibilizers include one or more selected from citric acid, maleic acid, itaconic acid, and their anhydrides. Among them, maleic anhydride and citric acid are more preferred.

[0048] In this embodiment, the preferred content of the compatibilizer (c) is 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass, when the total amount of (a) polyamide and (b) polyphenylene ether is 100 parts by mass.

[0049] [(d) Polyhydric alcohol] The (d) polyhydric alcohol of this embodiment (hereinafter sometimes simply referred to as the "(d) component") is not particularly limited as long as it has two or more hydroxyl groups and a number average molecular weight (Mn) of less than 500. Specifically, sugar alcohols such as sorbitol, mannitol, and pentaerythritol; sugar alcohol polymers such as dipentaerythritol and tripentaerythritol; amide group-containing polyhydric alcohols such as N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide, N,N'-bis(2-hydroxyethyl)adipamide, and hexamethylenehydroxystearic acid amide; amino group-containing polyhydric alcohols such as polyoxyethylene dodecylamine and polyoxyethylene octadecylamine; allylated ethers having a polyalkylene ether unit such as polyoxyethylene allylated ether; polyoxyethylene lauryl ether; polyoxyethylene allylated ether; Examples of the polyoxyethylene alkyl ethers include ethylene tridodecyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, and other polyoxyethylene alkylphenyl ethers, such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether, and dihydric alcohols having a polyalkylene ether unit, such as polyepichlorohydrin ether, polyoxyethylene bisphenol A ether, polyoxyethylene ethylene glycol, polyoxypropylene bisphenol A ether, and polyoxyethylene polyoxypropylene glycol ether.

[0050] The inclusion of component (d) achieves a balance of fluidity, heat resistance, and dart impact strength during injection molding, and also tends to maintain fluidity and dart impact strength during repeated extrusion. Although the mechanism is unclear, it is believed that the OH groups within the molecule act to relax the intermolecular forces of (a) polyamide, improving fluidity while maintaining heat resistance, and that the increased bonding strength at the interface between (a) polyamide and (b) polyphenylene ether results in excellent dart impact strength. Furthermore, by plasticizing (b) polyphenylene ether, the dispersed size of the (b) polyphenylene ether dispersed phase is maintained during repeated extrusion, thereby maintaining dart impact strength.

[0051] In this embodiment, from the perspective of compatibility, it is preferable that (d) the polyhydric alcohol contains one or more of an amide structure, an ether structure, and an ester structure.

[0052] From the perspectives of achieving good fluidity and surface impact strength during injection molding and maintaining heat resistance, the number average molecular weight (Mn) of component (d) is less than 500, preferably 400 or less, and particularly preferably 350 or less. Also, it is preferably 130 or more, more preferably 180 or more, and still more preferably 250 or more. Note that the number average molecular weight (Mn) of component (d) refers to the value measured by gel permeation chromatography (GPC). Further, component (d) preferably has one or more secondary or lower alcohols in the molecule, more preferably one or more primary alcohols in the molecule. Still more preferably, it has two or more primary alcohols in the molecule.

[0053] When the total amount of (a) polyamide and (b) polyphenylene ether is 100 parts by mass, the content of (d) polyhydric alcohol in this embodiment is 0.3 to 5 parts by mass, preferably 0.5 to 3 parts by mass, and more preferably 0.5 to 2 parts by mass. With the content within the above range, the additive effect of component (d) can be fully exerted, and bleeding out can be more effectively prevented.

[0054] [(e) Impact modifier] In this embodiment, (e) an impact modifier (hereinafter may be simply referred to as “component (e)”) may be further included. The impact modifier (e) in this embodiment refers to a non-hydrogenated block copolymer containing at least one aromatic vinyl polymer block mainly composed of aromatic vinyl monomer units and at least one conjugated diene polymer block mainly composed of conjugated diene monomer units and / or a hydrogenated product of the block copolymer.

[0055] With regard to the aromatic vinyl polymer block, the phrase "mainly composed of aromatic vinyl monomer units" refers to a block in which aromatic vinyl monomer units account for 50% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and most preferably 90% by mass or more. Similarly, the term "mainly composed of conjugated diene monomer units" in the above conjugated diene polymer block refers to a block in which 50% by mass or more of conjugated diene monomer units are more preferably 70% by mass or more, even more preferably 80% by mass or more, and most preferably 90% by mass or more of conjugated diene monomer units.

[0056] The aromatic vinyl polymer block may be, for example, a copolymer block in which a small amount of a conjugated diene compound is randomly bonded to an aromatic vinyl polymer block. Similarly, the conjugated diene polymer block may be, for example, a copolymer block in which a small amount of an aromatic vinyl compound is randomly bonded to a conjugated diene polymer block.

[0057] The aromatic vinyl compound used to form the aromatic vinyl monomer unit is not particularly limited, and examples thereof include styrene, α-methylstyrene, vinyltoluene, etc., and one or more compounds selected from these can be used, with styrene being particularly preferred.

[0058] The conjugated diene compound used to form the conjugated diene polymer block is not particularly limited, and examples thereof include butadiene, isoprene, piperylene, 1,3-pentadiene, etc., and one or more compounds selected from these can be used. Among these, butadiene, isoprene, and combinations thereof are preferred.

[0059] The microstructure of the conjugated diene polymer block portion of the block copolymer preferably has a 1,2-vinyl content or a total amount of 1,2-vinyl content and 3,4-vinyl content (total vinyl bond amount) of 5 to 80%, more preferably 10 to 50%, and even more preferably 15 to 40%. The total vinyl bond amount can be measured using an infrared spectrophotometer.

[0060] The non-hydrogenated block copolymer used for the production of the hydrogenated product (hydrogenated block copolymer) of the block copolymer is preferably a block copolymer in which the aromatic vinyl polymer block (a) and the conjugated diene polymer block (b) have a bonding form selected from a-b type, a-b-a type, and a-b-a-b type. Among these, block copolymers having different bonding forms may be combined and used. Among these, it is more preferably a bonding form selected from a-b-a type and a-b-a-b type, and even more preferably an a-b-a type bonding form.

[0061] Further, the impact modifier (e) used in this embodiment is preferably a partially hydrogenated block copolymer (partially hydrogenated block copolymer).

[0062] The partially hydrogenated block copolymer refers to a product obtained by subjecting the above non-hydrogenated block copolymer to a hydrogenation treatment to control the aliphatic double bonds of the conjugated diene polymer block in a range exceeding 0% and less than 100%. The preferred hydrogenation rate of the partially hydrogenated block copolymer is 50% or more and less than 100%, more preferably 80% or more and less than 100%, and most preferably 98% or more and less than 100%. When it is within this range, it can be particularly preferably used for electrical and electronic components such as nectar, breaker, and magnet switch, electrical components in the automotive field represented by relay blocks, and components in aircraft.

[0063] Furthermore, the impact improver (e) used in this embodiment preferably has a number average molecular weight of 150,000 or more but less than 300,000. When the molecular weight is within this range, a composition with excellent fluidity and impact strength can be obtained.

[0064] The method for evaluating the number-average molecular weight of the (e) impact modifier in a resin composition is as follows. Specifically, a mixture of (b) polyphenylene ether and (e) impact modifier in the composition is separated as an insoluble fraction using a solvent that is soluble in (a) polyamide but poorly soluble in (b) polyphenylene ether and (e) impact modifier, such as aqueous formic acid. The (e) impact modifier is then separated from the insoluble fraction using a solvent that is soluble in (e) impact modifier but poorly soluble in (b) polyphenylene ether, such as chloroform. This is measured using a gel permeation chromatography (GPC) system 21 (Showa Denko K.K.) and an ultraviolet spectrophotometer (UV-41 (Showa Denko K.K.)), and the number-average molecular weight is calculated using standard polystyrene. The measurement conditions may be as follows: solvent: chloroform, temperature: 40°C, columns: sample side (KG, K-800RL, K-800R), reference side (K-805L x 2), flow rate: 10 mL / min, measurement wavelength: 254 nm, pressure: 15 to 17 kg / cm 2 )]. Furthermore, when measuring the number average molecular weight, low molecular weight components may be detected due to catalyst deactivation during polymerization. In such cases, these low molecular weight components are not included in the molecular weight calculation. The low molecular weight components refer to components with a molecular weight of 3,000 or less. The calculated correct molecular weight distribution (weight average molecular weight / number average molecular weight) is usually within the range of 1.0 to 1.1.

[0065] These block copolymers that can be used in these embodiments as (e) impact modifiers may be of different bonding forms, different aromatic vinyl compound species, different conjugated diene compound species, different 1,2-bond vinyl contents or different 1,2-bond vinyl contents and 3,4-bond vinyl contents, different aromatic vinyl compound component contents, different hydrogenation rates, etc., and two or more of each may be mixed and used as long as it does not go against the gist of the present invention. Also, these block copolymers that can be used in this embodiment as (e) impact modifiers may be block copolymers that are wholly or partially modified. The modified block copolymer referred to here means a block copolymer modified with at least one kind of modified compound having at least one carbon-carbon double bond or triple bond and at least one carboxylic acid group, acid anhydride group, amino group, hydroxyl group or glycidyl group in the molecular structure. As the method for producing the modified block copolymer, in the presence or absence of a radical initiator, (1) a method of melt-kneading and reacting with a modified compound in a temperature range of not lower than the softening point temperature of the block copolymer and not higher than 250°C, (2) a method of reacting the block copolymer with the modified compound in a solution at a temperature lower than the softening point of the block copolymer, (3) a method of reacting the block copolymer with the modified compound without melting at a temperature lower than the softening point of the block copolymer, etc. may be mentioned, and any of these methods may be used, but the method (1) is preferred, and among them, the method carried out in the presence of a radical initiator is most preferred. As the "at least one kind of modified compound having at least one carbon-carbon double bond or triple bond and at least one carboxylic acid group, acid anhydride group, amino group, hydroxyl group or glycidyl group in the molecular structure" referred to here, the same modified compounds as those described for the modified polyphenylene ether can be used.

[0066] In this embodiment, the preferred content of the (e) impact modifier is 3 to 20 parts by mass, more preferably 5 to 15 parts by mass, and still more preferably 5 to 10 parts by mass, when the total amount of (a) polyamide and (b) polyphenylene ether is 100 parts by mass.

[0067] [Flame retardant] In this embodiment, a flame retardant may be further included. Examples of the flame retardant include inorganic flame retardants such as magnesium hydroxide and aluminum hydroxide; nitrogen-containing cyclic compounds such as melamine, cyanuric acid, and salts thereof; organic phosphate esters such as triphenyl phosphate, triphenyl phosphate hydroxide, bisphenol A bis(diphenyl phosphate), and derivatives thereof; nitrogen-containing phosphate compounds such as ammonium polyphosphate and melamine polyphosphate; phosphazene compounds described in JP-A-11-181429; boric acid compounds such as zinc borate; silicone oils; red phosphorus; phosphinates described in WO 2007 / 055147; mixtures thereof; and the like. Among them, nitrogen-containing cyclic compounds, organic phosphate esters, nitrogen-containing phosphate compounds, phosphazene compounds, boric acid compounds, silicone oils, and phosphinates are preferred, and bisphenol A bis(diphenyl phosphate) and its derivatives, phosphinates, and mixtures thereof are more preferred.

[0068] The content of the flame retardant in the resin composition of this embodiment is preferably 5 to 30 parts by mass with respect to 100 parts by mass of the total amount of (a) polyamide and (b) polyphenylene ether. In particular, when (e) an impact modifier is included, it is preferably 5 to 25 parts by mass with respect to 100 parts by mass of the total amount of (a) polyamide, (b) polyphenylene ether, and (e) impact modifier.

[0069] [Colorant] In this embodiment, there is no particular limitation on the method for coloring the resin composition, and one or more colorants selected from known organic dyes and pigments and inorganic pigments can be used. Examples of organic dyes and pigments include azo pigments such as azo lake pigments, benzimidazolone pigments, diarylide pigments, and condensed azo pigments; phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green; condensed polycyclic pigments such as isoindolinone pigments, quinophthalone pigments, quinacridone pigments, perylene pigments, anthraquinone pigments, perinone pigments, and dioxazine violet; azine pigments; and carbon black.

[0070] Among these, the carbon black should have a dibutyl phthalate (DBP) absorption of less than 250 mL / 100 g, preferably less than 150 mL / 100 g, and a nitrogen adsorption specific surface area of 900 m 2 / g, more preferably less than 400m 2 When these are in this range, a composition that is particularly excellent in colorability, mechanical strength, and flame retardancy can be obtained. The DBP absorption amount and nitrogen adsorption specific surface area referred to here are values measured by the methods specified in ASTM D2414 and JIS K6217, respectively.

[0071] Examples of azine dyes include Solvent Black 5 (CI 50415, CAS No. 11099-03-9), Solvent Black 7 (CI 50415:1, CAS No. 8005-20-5 / 101357-15-7), and Acid Black 2 (CI 50420, CAS No. 8005-03-6 / 68510-98-5) in the Color Index.

[0072] Examples of inorganic pigments include metal oxides other than iron oxide, such as titanium oxide, zinc oxide, and chromium oxide, and composite metal oxides such as titanium yellow, cobalt blue, and ultramarine.

[0073] The preferred amounts of the colorants added, when the total amount of the resin composition is 100% by mass, are 2% by mass or less for carbon black, 2% by mass or less for azine dyes, and 8% by mass or less for inorganic pigments. More preferred amounts are 1% by mass or less for carbon black, 1% by mass or less for azine dyes, and 5% by mass or less for inorganic pigments. By adding in the above addition amount, the balance of impact resistance and mechanical properties can be maintained well. Also, in the case of applications where flame retardancy is required, from the perspective of flame retardancy, the above addition amount is preferable.

[0074] [Other additives] In the present embodiment, in addition to the above-described components, inorganic fillers and other additive components can be added at any stage as necessary within a range not impairing the effects of the present invention.

[0075] Examples of the inorganic filler include fibrous, granular, plate-like, or needle-like inorganic reinforcing materials such as glass fiber, potassium titanate fiber, gypsum fiber, brass fiber, ceramic fiber, boron whisker fiber, mica, talc, silica, calcium carbonate, kaolin, calcined kaolin, wollastonite, zonotrite, apatite, glass beads, glass flakes, and titanium oxide. These inorganic fillers can be used in combination of two or more. Among these, more preferable inorganic fillers include glass fiber, carbon fiber, and glass beads. Also, the inorganic filler may be one surface-treated by a known method using a surface treatment agent such as a silane coupling agent. However, since natural ore-based fillers often contain a trace amount of iron element, it is necessary to select and use a purified one excluding the iron element. Specific preferable addition amounts of the inorganic filler are each 15% by mass or less, more preferably 13% by mass or less, and still more preferably 10% by mass or less when the entire resin composition is 100% by mass. Also, as for the entire inorganic filler, it is preferably 30% by mass or less, more preferably 25% by mass or less, and still more preferably 20% by mass or less when the entire resin composition is 100% by mass.

[0076] Examples of other additive components include other thermoplastic resins such as polyesters and polyolefins, plasticizers (low-molecular-weight polyolefins, polyethylene glycol, fatty acid esters, etc.), antistatic agents, nucleating agents, flow improvers, anti-dripping agents, reinforcing agents, various peroxides, spreading agents, organic heat stabilizers typified by copper-based heat stabilizers and hindered phenol-based antioxidants, antioxidants, ultraviolet absorbers, and light stabilizers.

[0077] The specific preferred amounts of the other additive components added are 15% by mass or less, more preferably 13% by mass or less, and even more preferably 10% by mass or less, when the entire resin composition is taken as 100% by mass. Furthermore, the total amount of other additive components is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less, when the entire resin composition is taken as 100% by mass.

[0078] In evaluating the bleeding-out phenomenon of the resin composition of this embodiment, it is preferable that the additive does not bleed onto the surface of the molded article after the experiment. The bleeding-out phenomenon is specifically evaluated by the method described in the Examples below.

[0079] The resin composition of the present embodiment preferably has a larger falling weight impact strength (J), which indicates an improvement in dart impact strength. The falling weight impact strength refers to a value measured by the method described in the Examples below.

[0080] The resin composition of this embodiment preferably has a larger melt volume flow rate (cc / 10 min), which indicates improved fluidity. The melt volume flow rate refers to a value measured by the method described in the Examples below.

[0081] The resin composition of this embodiment preferably has a larger deflection temperature under load (DTUL) (°C), which indicates improved heat resistance. Note that the heat deflection temperature under load (DTUL) refers to the value measured by the method described in the examples below.

[0082] (Method for producing resin composition) There is no particular limitation on the specific processing machine for obtaining the composition of the present embodiment. For example, a single-screw extruder, a twin-screw extruder, a roll, a kneader, a Brabender plastograph, a Banbury mixer, etc. can be mentioned. Among them, a twin-screw extruder is preferable, and in particular, a twin-screw extruder having an upstream supply port and at least one downstream supply port is most preferable. The melt-kneading temperature is preferably in the range of 280 to 340°C.

[0083] The melt-kneading for obtaining the resin composition of the present embodiment is not particularly limited. For example, it is preferable to melt-knead (b) polyphenylene ether and (c) compatibilizer, and then add (a) polyamide and (d) polyhydric alcohol and melt-knead them. Further, when the resin composition contains (e) impact modifier, it is preferable to melt-knead it together with (b) polyphenylene ether and (c) compatibilizer in the above melt-kneading. Specifically, it is preferable to use a twin-screw extruder having two supply ports, one each in the upstream and middle parts in the flow direction of the raw materials, and supply (b) polyphenylene ether, (c) compatibilizer, and optionally (e) impact modifier from the upstream supply port, and supply (a) polyamide and (d) polyhydric alcohol from the middle supply port.

[0084] (Molded article and method for producing the same) By molding the resin composition of the present embodiment using a molding method generally used for resin compositions, such as injection molding, extrusion molding, press molding, blow molding, calender molding, and casting molding, molded articles having various shapes can be produced. That is, the molded article of the present embodiment contains the resin composition of the present embodiment.

[0085] For example, a resin composition is melted in the cylinder of an injection molding machine whose cylinder temperature is adjusted to be within the range of (a) the melting point of the polyamide or higher and 350°C or lower, and then injected into a mold of a predetermined shape, thereby producing a molded product of a predetermined shape. Alternatively, a fibrous molded article can be produced by melting the resin composition in an extruder whose cylinder temperature is adjusted to fall within the above range and then spinning it out through a die nozzle. Furthermore, the resin composition can be melted in an extruder with the cylinder temperature adjusted within the above range and extruded through a T-die to produce a film- or sheet-shaped molded product.

[0086] Furthermore, the molded article produced by such a method can be used in a state where a coating layer made of paint, metal, other types of polymers, etc. is formed on the surface of the molded article.

[0087] The resin composition of the present embodiment can be suitably used as a molding material for various parts for automobiles, electrical and electronic applications, industrial materials, engineering materials, daily necessities, household goods, and the like. [Example]

[0088] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. The raw materials and evaluation methods used in the examples and comparative examples are shown below.

[0089] [raw materials] (a) Polyamide (a-1) Polyamide 6,6 having a VR of 36, a terminal amino group concentration of 27 μmol / g, a terminal carboxyl group concentration of 81 μmol / g, and a terminal amino group concentration / terminal carboxyl group concentration ratio of 0.33 was used. (a-2) Polyamide 6,6 having a VR of 45, a terminal amino group concentration of 90 μmol / g, a terminal carboxyl group concentration of 36 μmol / g, and a terminal amino group concentration / terminal carboxyl group concentration ratio of 0.4 was used. (a-3) Polyamide 6,6 with a VR of 36, a terminal amino group concentration of 80 μmol / g, a terminal carboxyl group concentration of 45 μmol / g, and a ratio of terminal amino group concentration / terminal carboxyl group concentration of 0.56 was used. (a-4) Polyamide 6,6 with a VR of 45, a terminal amino group concentration of 53 μmol / g, a terminal carboxyl group concentration of 95 μmol / g, and a ratio of terminal amino group concentration / terminal carboxyl group concentration of 0.56 was used. Note that the VR of (a) polyamide was measured at 25 °C using a solution prepared by dissolving (a) polyamide in 90% by mass formic acid (10% by mass water) to a concentration of 8.4% by mass in accordance with ASTM-D789. Also, the terminal amino group concentration and terminal carboxyl group concentration of (a) polyamide were measured by 1H-NMR according to the measurement method described in the examples of JP-A-7-228689. 1

[0090] (b) Polyphenylene ether (PPE) A polyphenylene ether resin obtained by oxidative polymerization of 2,6-xylenol was used. The reduced viscosity of the polyphenylene ether resin (measured at 0.5 g / dL, chloroform solution, 30 °C) was 0.40 dL / g.

[0091] (c) Compatibilizer Maleic anhydride (manufactured by NOF Corporation, "Crystal MAN")

[0092] (d) Polyhydric alcohol Dipentaerythritol (manufactured by Perstorp, "Dipenta-90") (a hexavalent alcohol with a melting point of 217-222 °C, a number average molecular weight of 254.28, and containing an ether structure) was used.

[0093] (e) Impact modifier A copolymer composed of polystyrene-hydrogenated polybutadiene-polystyrene blocks (manufactured by TSRC (Nanton) Industries.Ltd, "TAIPOL 6154-364-A") was used.

[0094] [Evaluation method] The evaluation tests carried out in the examples and comparative examples were carried out as follows.

[0095] (1)(a) Formation of a continuous phase using polyamide The obtained pellets of the resin composition were fed into a small injection molding machine (product name: IS-100GN, manufactured by Toshiba Machine Co., Ltd.) with a cylinder temperature set to 270-290°C, and ISO dumbbells for evaluation were produced under the following conditions: mold temperature 90°C, injection pressure 70 MPa, injection time 20 seconds, and cooling time 15 seconds. The three ISO dumbbells were stained as follows. Test pieces measuring 5 mm long (in the direction of resin flow) × 5 mm wide × 4 mm thick were cut from the center of three of the above ISO dumbbells. To add length to these test pieces, a 5 mm long × 5 mm wide × 4 mm thick high-impact polystyrene test piece was attached with instant adhesive to prepare a 10 mm long × 5 mm wide × 4 mm thick test piece for staining. A 1 mm square flat surface for cutting thin film sections was prepared on the short side of the test piece for staining, facing the resin composition, using an ultramicrotome (ULTRACUT-N manufactured by Reichert-Nissei). Next, the above-mentioned test piece for dyeing was immersed in a 10% by mass aqueous solution of phosphotungstic acid placed in a heat-resistant container, heated in a water bath at 80°C for 4 hours, then removed and cooled to room temperature. Thereafter, the test piece for dyeing was removed from the heat-resistant container, washed with water, and dried. Next, using the ultramicrotome equipped with a diamond knife filled with water, a 1 mm square, 85 nm thick thin film was cut out from the flat surface of the staining specimen onto the water, and the thin film was scooped up with a Cu mesh for SEM observation. The Cu mesh with the thin film on it was placed on a stainless steel net. This staining procedure stained (a) polyamide, (c) compatibilizer, and (d) polyhydric alcohol, making them appear white when observed under a scanning electron microscope. Furthermore, (b) polyphenylene ether and (e) impact modifier were not stained, making them appear black when observed under a scanning electron microscope. It is believed that (e) impact modifier is contained in the dispersed phase formed by (b) polyphenylene ether. The dyed test piece was photographed using a scanning electron microscope (product name "SU8220", manufactured by Hitachi High-Technologies Corporation) at a magnification of 5,000 and an accelerating voltage of 4.0 kV. The obtained images were observed, and (a) the case where the polyamide-containing phase formed a continuous phase (a white continuous phase was observed) was judged as "Good."

[0096] (2) Melt Volume Flow Rate (MVR) The MVR (cc / 10 min) of the resulting resin composition pellets was measured in accordance with ISO1133 at 280° C. under a load of 2.16 kg. The larger the value, the better the fluidity was judged to be.

[0097] (3) Fluidity after repeated extrusion For the pellets of the resin compositions obtained in the following Examples and Comparative Examples after repeated extrusion, MVR (cc / 10 min) was measured at 280° C. under a load of 2.16 kg in accordance with ISO1133. The fluidity after repeated extrusion was evaluated as follows: pellets with an MVR retention rate of 90% or more compared to the pellets before repeated extrusion were rated as "Excellent", pellets with an MVR retention rate of 80% or more but less than 90% were rated as "Good", and pellets with an MVR retention rate of less than 80% were rated as "Poor".

[0098] (4) Drop weight impact strength The obtained resin composition pellets were fed into a small injection molding machine (product name: IS-100GN, manufactured by Toshiba Machine Co., Ltd.) with a cylinder temperature set to 270-290°C, and molded into a 75mm x 75mm x 3mm flat plate under the following conditions: mold temperature 90°C, injection pressure 70MPa, injection time 20 seconds, and cooling time 15 seconds. The obtained flat plate was subjected to a drop weight impact test in accordance with JIS K 7211-1 in an environment of 23°C using a striker with a tip diameter of 20 mm, and the total absorbed energy (J) required to break the test piece was measured. The larger the value, the better the dart impact strength was judged to be.

[0099] (5) Drop weight impact strength after repeated extrusion Pellets of the resin compositions obtained in the following Examples and Comparative Examples after repeated extrusion were fed into a small injection molding machine (product name: IS-100GN, manufactured by Toshiba Machine Co., Ltd.) with a cylinder temperature set to 270-290°C, and molded into flat plates measuring 75 mm x 75 mm x 3 mm under the following conditions: mold temperature 90°C, injection pressure 70 MPa, injection time 20 seconds, and cooling time 15 seconds. The obtained flat plate was subjected to a drop weight impact test in accordance with JIS K 7211-1 in an environment of 23°C using a striker with a tip diameter of 20 mm, and the total absorbed energy (J) required to break the test piece was measured. The dart impact strength after repeated extrusion was evaluated based on the following criteria: pellets with a total absorbed energy retention rate of 90% or more compared to the pellets before repeated extrusion were rated as "Excellent" (◎), pellets with a total absorbed energy retention rate of 80% or more but less than 90% were rated as "Good" (◯), and pellets with a total absorbed energy retention rate of less than 80% were rated as "Poor" (×).

[0100] (6) Deflection temperature under load (DTUL) The pellets of the obtained resin composition were supplied to a small injection molding machine (trade name: IS-100GN, manufactured by Toshiba Machine Co., Ltd.) with the cylinder temperature set at 270 - 290 °C, and an ISO dumbbell for evaluation was produced under the conditions of a mold temperature of 90 °C, an injection pressure of 70 MPa, an injection time of 20 seconds, and a cooling time of 15 seconds. Further, the ISO dumbbell was cut to produce a test piece for measuring the heat deflection temperature (DTUL). Using the above test piece for measuring the heat deflection temperature, the heat deflection temperature DTUL (ISO 75, 0.45 MPa load) was measured. It was determined that the larger the value, the better the heat resistance.

[0101] (7) Bleed-out The pellets of the obtained resin composition were supplied to a small injection molding machine (trade name: IS-100GN, manufactured by Toshiba Machine Co., Ltd.) with the cylinder temperature set at 270 - 290 °C, and molded into a flat plate of 50 mm × 90 mm × 2 mm under the conditions of a mold temperature of 80 °C, an injection pressure of 70 MPa, an injection time of 10 seconds, and a cooling time of 15 seconds. The produced molded product was placed in an oven at 120 °C, and after 100 hours, it was checked whether powdery substances were deposited (bleed-out) on the surface of the molded product. Those with no bleed-out at all were evaluated as "◎ (excellent)", those with partial occurrence were evaluated as "〇 (good)", and those with overall occurrence were evaluated as "× (poor)".

[0102] [Examples 1 - 6, Comparative Examples 1 - 4] As a manufacturing apparatus for the resin composition, a twin-screw extruder ZSK-25 (manufactured by Coperion) was used. In this twin-screw extruder, a total of 2 supply ports, one at the upstream part and one at the middle part, were provided in the flow direction of the raw materials. At this time, vacuum vents were provided in the block immediately before the cylinder block with the middle supply port and the cylinder block immediately before the die. Also, the method of supplying raw materials to the supply port in the middle part was a method of supplying using a forced side feeder from the side opening of the extruder. Components (a) to (e) were fed into the twin-screw extruder set up as described above in the compositions shown in Table 1, with components (b), (c), and (e) fed from an upstream feed port and components (a) and (d) fed from a midstream feed port. They were melt-kneaded at an extrusion temperature of 280 to 320°C, a screw rotation speed of 400 rpm, and a discharge rate of 20 kg / hour to obtain pellets of the resin composition. To adjust the moisture content of the obtained pellets, after extrusion, they were dried in a dehumidifying dryer set at 120°C and then placed in an aluminum-coated moisture-proof bag. The moisture content of the pellets at this time was approximately 250 to 400 ppm. These pellets were used to perform various evaluation tests. Subsequently, the obtained pellets were melt-kneaded in a twin-screw extruder under conditions of an extrusion temperature of 280, a screw rotation speed of 300 rpm, and a discharge rate of 20 kg / hour to obtain pellets of the resin composition. This process was repeated twice to obtain pellets after repeated extrusion. To adjust the moisture content of the resulting pellets, after extrusion, they were dried in a dehumidifying dryer set at 120°C and then placed in an aluminum-coated moisture-proof bag. The moisture content of the pellets at this time was approximately 250 to 400 ppm. These pellets were used to evaluate fluidity after repeated extrusion and to test their drop impact strength. The evaluation results of the resin composition are shown in Table 1.

[0103] [Table 1] [Industrial Applicability]

[0104] By using the resin composition of the present invention, bleed-out is suppressed, and a resin composition having excellent heat resistance, fluidity, and dart impact strength, and excellent moldability for thin-walled parts can be obtained. Furthermore, the resin composition of the present invention is likely to retain its fluidity and dart impact strength even after repeated extrusion, making the material highly recyclable. As a result, the resin composition of the present invention has industrial applicability, such as being suitable for use as a molding material for various parts for automobiles, electrical and electronic applications, industrial materials, industrial materials, and daily necessities and household goods.

Claims

1. (a) a polyamide, (b) a polyphenylene ether, (c) a compatibilizer for the (a) polyamide and the (b) polyphenylene ether, (d) a polyhydric alcohol having two or more hydroxyl groups and a number average molecular weight (Mn) of less than 500, and (e) as an impact modifier, including a block copolymer containing at least one block mainly composed of an aromatic vinyl monomer unit and at least one block mainly composed of a conjugated diene monomer unit and / or a hydrogenated product of the block copolymer, with respect to 100 parts by mass of the total amount of the (a) polyamide and the (b) polyphenylene ether, the content of the (d) polyhydric alcohol is 0.3 to 5 parts by mass, the ratio of the terminal amino group concentration of the (a) polyamide to the terminal carboxyl group concentration (terminal amino group concentration / terminal carboxyl group concentration) is 0.3 to 0.5, A resin composition, characterized in that the (a) polyamide forms a continuous phase.

2. With respect to 100 parts by mass of the total amount of the (a) polyamide and the (b) polyphenylene ether, the content of the (a) polyamide is 40 to 90 parts by mass, and the content of the (b) polyphenylene ether is 10 to 60 parts by mass. The resin composition according to Claim 1.

3. The resin composition according to Claim 1 or 2, wherein the formic acid relative viscosity (VR) of the (a) polyamide is 30 to 40.

4. The resin composition according to any one of Claims 1 to 3, wherein the (a) polyamide is polyamide 6,6.

5. The resin composition according to any one of Claims 1 to 4, wherein the (d) polyhydric alcohol is dipentaerythritol.

6. A molded article, characterized by containing the resin composition according to any one of Claims 1 to 5.

7. The molded article according to Claim 6, which is a component for automotive electrical and electronic applications.

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