Polyphenylene ether resin composition and molded article

Abstract

The purpose of the present invention is to provide a resin composition which exhibits excellent tracking resistance and which can yield a rigid molded article. The present invention is a poly(phenylene ether) resin composition which contains: (a) a resin component; (b) titanium oxide; and (c) an inorganic filler. The inorganic filler (c) has a thermal conductivity of 2-12 [W / (m·K)]. The resin component (a) contains 50-90 parts by mass of (a1) a poly(phenylene ether) relative to 100 parts by mass of the resin component (a). The amount of titanium oxide (b) is 5-40 parts by mass relative to 100 parts by mass of the resin component (a). The amount of the inorganic filler (c) is 5-50 parts by mass relative to 100 parts by mass of the resin component (a). The mass ratio of titanium oxide (b) and the inorganic filler (c) ((b) / (c)) is 0.2-8.0.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority from Japanese Patent Application No. 2021-055524, filed on March 29, 2021, the contents of which are incorporated herein by reference. [Technical field]

[0002] The present invention relates to a polyphenylene ether resin composition and a molded article. [Background technology]

[0003] In the field of electrical and electronic equipment, to ensure safety against ignition due to electrical load, it is necessary for the equipment to have excellent tracking resistance, which is one of the electrical properties. In recent years, the miniaturization and high density of electrical and electronic equipment parts and electrical components have progressed rapidly. As a result, the insulation distance has become shorter, and the requirements for the tracking resistance of these parts (molded products) have become increasingly strict (see Patent Document 1).

[0004] Furthermore, there is an increasing demand for rigidity in the housings of electric and electronic equipment components and electrical components (see Patent Document 2).

[0005] In order to meet the demand for tracking resistance, for example, a technique is known in which the tracking resistance is improved by adding titanium oxide to a thermoplastic resin (see Patent Documents 3 and 4). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2016-183294 A [Patent Document 2] JP 2001-316587 A [Patent Document 3] Patent No. 5405738 [Patent Document 4] International Publication No. 2015 / 002145 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the thermoplastic resin compositions disclosed in these conventional techniques still have a problem in terms of achieving both high tracking resistance and rigidity.

[0008] In view of the above problems, an object of the present invention is to provide a resin composition which is capable of producing a molded article having excellent tracking resistance and rigidity. [Means for solving the problem]

[0009] The present inventors conducted extensive research to solve the above problems and have now completed the present invention.

[0010] That is, the present invention is as follows. [1] (a) a resin component; (b) titanium dioxide; (c) an inorganic filler; Including, The (c) inorganic filler has a thermal conductivity of 2 to 12 [W / (m K)], The (a) resin component contains 50 to 90 parts by mass of (a1) polyphenylene ether per 100 parts by mass of the (a) resin component, the amount of the (b) titanium oxide is 5 to 40 parts by mass relative to 100 parts by mass of the (a) resin component, The amount of the (c) inorganic filler is 5 to 50 parts by mass relative to 100 parts by mass of the (a) resin component, and A polyphenylene ether resin composition, wherein a mass ratio ((b) / (c)) of the (b) titanium oxide to the (c) inorganic filler is 0.2 to 8.0. [2] The polyphenylene ether resin composition according to [1], wherein the (c) inorganic filler is at least one selected from the group consisting of (c-1) calcium silicate fibrous material and (c-2) talc. [3] The polyphenylene ether resin composition according to [2], wherein the (c) inorganic filler is the (c-1) calcium silicate-based fibrous material. [4] The polyphenylene ether resin composition according to [2], wherein the calcium silicate fibrous material (c-1) is wollastonite. [5] The polyphenylene ether resin composition according to any one of [1] to [4], wherein a total content of the (b) titanium oxide and the (c) inorganic filler is 15 to 90 parts by mass per 100 parts by mass of the (a) resin component. [6] The polyphenylene ether resin composition according to any one of [1] to [5], wherein the (a) resin component contains 1 to 49 parts by mass of an (a2) polystyrene-based resin per 100 parts by mass of the (a) resin component. [7] The polyphenylene ether resin composition according to any one of [1] to [6], wherein the (a) resin component contains 1 to 49 parts by mass of the (a3) ​​hydrogenated block copolymer per 100 parts by mass of the (a) resin component. [8] The polyphenylene ether resin composition according to any one of [1] to [7], further comprising, per 100 parts by mass of the resin component (a), 5 to 30 parts by mass of a phosphate ester-based flame retardant (d). [9] The polyphenylene ether resin composition according to [8], wherein the (d) phosphate ester-based flame retardant is a condensate of a phosphate ester.

[10] A molded article comprising the polyphenylene ether resin composition according to any one of [1] to [9]. Effect of the Invention

[0011] According to the present invention, it is possible to provide a resin composition which is capable of giving a molded article having excellent tracking resistance and imparted rigidity. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, the embodiment for carrying out the present invention (hereinafter, also referred to as "the present embodiment") will be described in detail. Note that the present invention is not limited to the following embodiment, and can be carried out in various modifications within the scope of the spirit thereof.

[0013] In this embodiment, (a) the resin component, (b) titanium oxide, (c) the inorganic filler, (d) the phosphate ester-based flame retardant, (a1) polyphenylene ether, (a2) the polystyrene-based resin, (a3) ​​the hydrogenated block copolymer, (c-1) the calcium silicate-based fibrous material, and (c-2) talc may be simply referred to as the (a) component, the (b) component, the (c) component, the (d) component, the (a1) component, the (a2) component, the (a3) ​​component, the (c-1) component, and the (c-2) component, respectively.

[0014] In the present embodiment, unless otherwise specified, the numerical range is intended to include the lower and upper limits of the range, for example, 50 to 90 parts by mass means 50 parts by mass or more and 90 parts by mass or less.

[0015] [Polyphenylene ether resin composition] The polyphenylene ether resin composition of the present embodiment (hereinafter, simply referred to as "the resin composition of the present embodiment") has (a) a resin component; (b) titanium dioxide; (c) an inorganic filler; Including, The (c) inorganic filler has a thermal conductivity of 2 to 12 [W / (m K)], The (a) resin component contains 50 to 90 parts by mass of (a1) polyphenylene ether per 100 parts by mass of the (a) resin component, the amount of the (b) titanium oxide is 5 to 40 parts by mass relative to 100 parts by mass of the (a) resin component, The amount of the (c) inorganic filler is 5 to 50 parts by mass relative to 100 parts by mass of the (a) resin component, and The mass ratio ((b) / (c)) of the (b) titanium oxide to the (c) inorganic filler is 0.2 to 8.0. This configuration makes it possible to obtain a molded product having excellent tracking resistance and rigidity.

[0016] The components of the resin composition of the present embodiment will be illustrated below.

[0017] [(a) Resin component] The resin component (a) in the resin composition of the present embodiment includes at least (a1) polyphenylene ether. Examples of the resin component (a) other than (a1) polyphenylene ether include (a2) polystyrene resin and (a3) ​​hydrogenated block copolymer.

[0018] [(a1) Polyphenylene ether] Examples of (a1) polyphenylene ether 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), etc. Examples of (a1) polyphenylene ether include copolymers of 2,6-dimethylphenol and other phenols. Examples of such copolymers include copolymers of 2,6-dimethylphenol and 2,3,6-trimethylphenol; and copolymers of 2,6-dimethylphenol and 2-methyl-6-butylphenol. Among these, particularly preferred polyphenylene ethers are poly(2,6-dimethyl-1,4-phenylene ether), copolymers of 2,6-dimethylphenol and 2,3,6-trimethylphenol, or mixtures thereof.

[0019] A portion of the terminal groups of the polyphenylene ether may contain dibutylamine. The presence of dibutylamine in a portion of the terminal groups of the polyphenylene ether can be identified by a peak appearing at 3.620 ppm in NMR.

[0020] The (a1) polyphenylene ether can be produced by a known method. Examples of the method for producing the (a1) polyphenylene ether include the methods described in U.S. Pat. Nos. 3,306,874, 3,306,875, 3,257,357, 3,257,358, JP-A-50-51197, JP-B-52-17880, and JP-B-63-152628.

[0021] (a1) The reduced viscosity of the polyphenylene ether (0.5 g / dL chloroform solution, 30° C., measured with an Ubbelohde viscometer) is preferably in the range of 0.30 dL / g to 0.80 dL / g, more preferably 0.35 dL / g to 0.75 dL / g, and most preferably 0.38 dL / g to 0.55 dL / g, from the viewpoints of impact resistance and heat resistance of the molded article.

[0022] The (a1) polyphenylene ether may be used alone or in combination of two or more different types differing in composition, molecular weight, reduced viscosity, etc.

[0023] To stabilize the polyphenylene ether, known stabilizers can be suitably used. Examples of the stabilizer include metal stabilizers such as zinc oxide and zinc sulfide; and organic stabilizers such as hindered phenol stabilizers, phosphorus stabilizers, and hindered amine stabilizers. The preferred blending amount of the stabilizer is less than 5 parts by mass per 100 parts by mass of the (a1) polyphenylene ether.

[0024] Furthermore, known additives that can be added to polyphenylene ether may be added in an amount of less than 10 parts by mass per 100 parts by mass of the polyphenylene ether (a1).

[0025] The content of (a1) polyphenylene ether is 50 to 90 parts by mass, and preferably 50 to 80 parts by mass, per 100 parts by mass of the resin component, from the viewpoint of achieving a sufficiently good balance between tracking resistance and rigidity.

[0026] [(a2) Polystyrene resin] As the (a) resin component, (a2) a polystyrene-based resin can be used.

[0027] (a2) Examples of polystyrene resins include homopolymers of styrene compounds and copolymers of styrene compounds with other monomers.

[0028] The (a2) polystyrene-based resin may be used alone or in combination of two or more kinds.

[0029] In one embodiment, when the (a2) polystyrene resin is a copolymer of a styrene compound and another monomer, the amount of the structural unit derived from the styrene compound in the copolymer is 5% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass or more. In another embodiment, when the (a2) polystyrene resin is a copolymer of a styrene compound and another monomer, the amount of the structural unit derived from the styrene compound in the copolymer is 95% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, or 5% by mass or less.

[0030] Examples of styrene-based compounds include styrene, α-methylstyrene, 2,4-dimethylstyrene, monochlorostyrene, p-methylstyrene, p-tert-butylstyrene, ethylstyrene, etc. From the viewpoint of practicality of the raw material, styrene is preferred.

[0031] Examples of monomers other than styrene-based compounds include methacrylic acid esters such as methyl methacrylate and ethyl methacrylate; acid anhydrides such as maleic anhydride; and α-olefins such as ethylene.

[0032] (a2) The polystyrene resin may be, for example, atactic polystyrene, rubber-reinforced polystyrene, etc. The rubber-reinforced polystyrene may be, for example, high-impact polystyrene, etc. (a2) The polystyrene resin is preferably at least one selected from the group consisting of atactic polystyrene and high-impact polystyrene.

[0033] The content of the (a2) polystyrene resin may be appropriately adjusted, and from the viewpoint of achieving a sufficiently good balance between processability, heat resistance, tracking resistance, and rigidity, it is 1 to 49 parts by mass, preferably 5 to 49 parts by mass, and more preferably 10 to 49 parts by mass, per 100 parts by mass of the (a) resin component. In one embodiment, the content of the (a2) polystyrene resin is 1 part by mass or more, 5 parts by mass or more, 10 parts by mass or more, 20 parts by mass or more, 30 parts by mass or more, 40 parts by mass or more, or 45 parts by mass or more, per 100 parts by mass of the (a) resin component. In another embodiment, the content of the (a2) polystyrene resin is 49 parts by mass or less, 45 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, 10 parts by mass or less, or 5 parts by mass or less, per 100 parts by mass of the (a) resin component.

[0034] [(a3) Hydrogenated block copolymer] As the (a) resin component, a (a3) ​​hydrogenated block copolymer can be used. The (a3) ​​hydrogenated block copolymer is a hydrogenated block copolymer obtained by hydrogenating a block copolymer of an aromatic vinyl compound and a conjugated diene compound. The block copolymer of an aromatic vinyl compound and a conjugated diene compound is, for example, a block copolymer of styrene and a conjugated diene compound, that is, a block copolymer consisting of a polystyrene block and a conjugated diene compound polymer block.

[0035] The hydrogenation rate of unsaturated bonds derived from the conjugated diene compound by hydrogenation is preferably 60% or more, more preferably 80% or more, and further preferably 95% or more, from the viewpoint of heat resistance stability.

[0036] When the block copolymer before hydrogenation is a block copolymer of styrene and a conjugated diene compound, the structure of the block copolymer before hydrogenation is, for example, SBS, SBSB, (SB-) where the styrene block chain is represented by S, the diene compound block chain is represented by B, and the silicon atom is represented by Si. 4 -Si, SBSBS, etc.

[0037] The microstructure of the diene compound polymer block can be selected arbitrarily.

[0038] The vinyl bond amount (total of 1,2-vinyl bonds and 3,4-vinyl bonds) of the conjugated diene compound polymer block is preferably 2 to 60%, more preferably 8 to 40%, based on the total bond amount (total of 1,2-vinyl bonds, 3,4-vinyl bonds and 1,4-conjugated bonds) of the diene compound polymer.

[0039] The number average molecular weight of the (a3) ​​hydrogenated block copolymer may be appropriately adjusted, and is preferably 100,000 to 400,000, more preferably 150,000 to 350,000, and even more preferably 200,000 to 300,000. When the number average molecular weight is 100,000 or more, a resin composition having excellent impact resistance is obtained. The impact resistance of the resin composition of the present embodiment is improved in proportion to the number average molecular weight of the (a3) ​​hydrogenated block copolymer. In addition, when the number average molecular weight of the (a3) ​​hydrogenated block copolymer is 400,000 or less, a polyphenylene ether resin composition having low load during melt extrusion and excellent processing flowability is obtained, and the dispersibility of the (a3) ​​hydrogenated block copolymer in the polyphenylene ether resin composition is excellent.

[0040] When the (a3) ​​hydrogenated block copolymer has a styrene polymer block chain, at least one of the styrene polymer block chains preferably has a number average molecular weight of 15,000 or more, more preferably 20,000 or more and 50,000 or less, and further preferably all of the styrene polymer block chains have number average molecular weights of 15,000 or more.

[0041] When the (a3) ​​hydrogenated block copolymer has a styrene polymer block chain, the proportion of the styrene polymer block chain in the (a3) ​​hydrogenated block copolymer is not particularly limited as long as at least one styrene polymer block chain has a number average molecular weight of 15,000 or more. From the viewpoint of impact resistance, the proportion is preferably 10 to 70 mass%, more preferably 20 to 50 mass%, and even more preferably 30 to 40 mass%.

[0042] As the (a3) ​​hydrogenated block copolymer, two or more kinds of hydrogenated block copolymers having different compositions or structures may be used in combination. For example, a hydrogenated block copolymer having a bound styrene polymer block content of 50% by mass or more and a hydrogenated block copolymer having a bound styrene polymer block content of 30% by mass or less may be used in combination, hydrogenated block copolymers having different molecular weights may be used in combination, or a block copolymer of styrene and a conjugated diene as described above may be used in combination with a hydrogenated random block copolymer obtained by hydrogenating a block copolymer containing a random copolymer block of styrene and a conjugated diene.

[0043] In this specification, the "bound styrene polymer block content" refers to the proportion of styrene polymer block chains in the (a3) ​​hydrogenated block copolymer.

[0044] The hydrogenated block copolymer (a3) ​​preferably has a Li (lithium) content as a residual metal component of 100 ppm by mass or less. By having a Li content of 100 ppm by mass or less, the resin composition of the present embodiment has excellent long-term heat aging resistance or flame retardancy after heat aging. From the same viewpoint, the Li content of the hydrogenated block copolymer (a3) ​​is more preferably 50 ppm by mass or less, and further preferably 20 ppm by mass or less.

[0045] The Li content can be measured by dry ashing, i.e., pretreating the sample by weighing it, placing it in a crucible, and heat-treating it at 500 to 600°C for 5 to 20 minutes using a burner or an electric furnace, and then applying ICP-AES using a Thermo Fisher Scientific iCAP6300 Duo.

[0046] The (a3) ​​hydrogenated block copolymer may be dispersed in the form of particles in the polyphenylene ether resin composition. When the (a3) ​​hydrogenated block copolymer is dispersed in the form of particles, the average particle size is preferably 0.1 to 3.0 μm, more preferably 0.2 to 2.0 μm, and even more preferably 0.3 to 1.0 μm. When the average particle size is 0.1 μm to 3.0 μm, the resin composition of the present embodiment has excellent impact resistance.

[0047] (a3) The average particle size of the hydrogenated block copolymer refers to the weight average particle size.

[0048] The content of the (a3) ​​hydrogenated block copolymer may be appropriately adjusted, and is, for example, in the range of 1 to 49 parts by mass, preferably 1 to 35 parts by mass, and more preferably 1 to 25 parts by mass, per 100 parts by mass of the (a) resin component. When the content of the (a3) ​​hydrogenated block copolymer is 1 part by mass or more, the resin composition of the present embodiment has excellent impact strength. On the other hand, when the content of the (a3) ​​hydrogenated block copolymer is 49 parts by mass or less, the resin composition has excellent compatibility with the (a3) ​​polyphenylene ether, high impact resistance, and excellent rigidity such as flexural modulus and flexural strength.

[0049] [(b) Titanium oxide] The titanium oxide (b) used in the resin composition of the present embodiment is not particularly limited, and any known titanium oxide can be used.

[0050] (b) The average primary particle size of titanium oxide is preferably 0.01 to 0.5 μm, more preferably 0.05 to 0.4 μm, and even more preferably 0.15 to 0.3 μm, from the viewpoint of the balance between dispersibility, white coloring ability, and handleability during production.

[0051] (b) Titanium oxide may contain at least one of the following surface treatment agents: oxides of metals such as aluminum, magnesium, titanium zirconia, and tin; hydrous oxides of these metals; salts of higher fatty acids such as stearic acid of these metals; and organosilicon compounds.

[0052] (b) Titanium oxide can be produced by a dry method or a wet method.

[0053] The crystal structure of (b) titanium oxide may be either rutile or anatase, with the rutile type being preferred from the standpoint of the white coloring ability and thermal stability of the thermoplastic resin composition used in this embodiment.

[0054] (b) The titanium oxide may be used alone or in combination of two or more kinds.

[0055] Within the range of the mass ratio of (b) to (c) of 0.2 to 8.0 described later, the content of titanium oxide (b) is 5 to 40 parts by mass, preferably 10 to 40 parts by mass, and more preferably 15 to 40 parts by mass, relative to 100 parts by mass of the resin component (a). If the content of titanium oxide (b) is 5 to 40 parts by mass, the balance between processability and tracking resistance performance can be sufficiently good. In one embodiment, the content of component (b) is 5 parts by mass or more, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, 25 parts by mass or more, 30 parts by mass or more, or 35 parts by mass or more relative to 100 parts by mass of component (a). In another embodiment, the content of component (b) is 40 parts by mass or less, 35 parts by mass or less, 30 parts by mass or less, 25 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, or 10 parts by mass or less relative to 100 parts by mass of component (a).

[0056] [(c) Inorganic filler] The resin composition of the present embodiment contains (c) an inorganic filler having a thermal conductivity of 2 to 12 [W / (m·K)]. It is considered that an inorganic filler having a thermal conductivity in this range has a higher thermal conductivity and a better heat dissipation property in the resin than, for example, a general inorganic filler such as glass fiber. Therefore, it is considered that it is difficult to form a carbonized conductive path, and the decrease in tracking resistance that may occur when adding an inorganic filler is small.

[0057] The component (c) is not particularly limited as long as it is an inorganic filler with a thermal conductivity of 2 to 12 [W / (m·K)], and examples thereof include (c-1) calcium silicate fibrous material and (c-2) talc.

[0058] [(c-1) Calcium silicate fibrous material] (c-1) Calcium silicate fibrous material exhibits an effect of maintaining the tracking resistance performance and an effect of improving the physical properties. (c-1) Calcium silicate fibrous material includes CaO and SiO 2 Among them, for example, wollastonite and xonotlite are preferable, and wollastonite is more preferable.

[0059] Wollastonite is CaO SiO 2 It has a composition shown below. There are natural and synthetic wollastonite. Natural wollastonite usually exists as an aggregate of fibers, and is crushed and classified before use. The aspect ratio (fiber length / fiber diameter) of natural wollastonite varies depending on the crushing method and place of origin. Synthetic products are almost uniform.

[0060] Xonotlite is 6CaO 6SiO 2 H 2 It has the composition represented by O. Xonotlite is available in both natural and synthetic forms.

[0061] [(c-2) Talc] Talc is a mineral containing magnesium hydroxide and silicate, and its chemical name is hydrous magnesium silicate. Talc is generally known as SiO 2The main components are approximately 60% silica, approximately 30% MgO, and 4.8% water of crystallization.

[0062] Talc may be treated with a surface treatment agent from the viewpoint of improving affinity with resin. Examples of the surface treatment agent include, but are not limited to, silane coupling agents such as aminosilane and epoxysilane; titanate coupling agents; fatty acids (saturated fatty acids, unsaturated fatty acids); alicyclic carboxylic acids; resin acids; and metal soaps. The amount of the surface treatment agent added is not particularly limited, but is preferably 3% by mass or less, more preferably 2% by mass or less, and most preferably not substantially added, relative to 100% by mass of talc.

[0063] In one embodiment, (c) the thermal conductivity of the inorganic filler is 2.0 [W / (m·K)] or more, 2.5 [W / (m·K)] or more, 3.0 [W / (m·K)] or more, 3.5 [W / (m·K)] or more, 4.0 [W / (m·K)] or more, 4.5 [W / (m·K)] or more, 5.0 [W / (m·K)] or more, 5.5 [W / (m·K)] or more, 6.0 [W / (m·K)] or more, 6.5 [W / ( m·K)] or more, 7.0[W / (m·K)] or more, 7.5[W / (m·K)] or more, 8.0[W / (m·K)] or more, 8.5[W / (m·K)] or more, 9.0[W / (m·K)] or more, 9.5[W / (m·K)] or more, 10.0[W / (m·K)] or more, 10.5[W / (m·K)] or more, 11.0[W / (m·K)] or more, or 11.5[W / (m·K)] or more. In another embodiment, the thermal conductivity of the inorganic filler (c) is 12.0 [W / (m·K)] or less, 11.5 [W / (m·K)] or less, 11.0 [W / (m·K)] or less, 10.5 [W / (m·K)] or less, 10.0 [W / (m·K)] or less, 9.5 [W / (m·K)] or less, 9.0 [W / (m·K)] or less, 8.5 [W / (m·K)] or less, 8.0 [W / (m·K)] or less, 7 .... 0.5 [W / (m·K)] or less, 7.0 [W / (m·K)] or less, 6.5 [W / (m·K)] or less, 6.0 [W / (m·K)] or less, 5.5 [W / (m·K)] or less, 5.0 [W / (m·K)] or less, 4.5 [W / (m·K)] or less, 4.0 [W / (m·K)] or less, 3.5 [W / (m·K)] or less, 3.0 [W / (m·K)] or less, or 2.5 [W / (m·K)] or less.

[0064] The (c) inorganic filler may be used alone or in combination of two or more kinds.

[0065] The resin composition of the present embodiment may or may not contain inorganic fillers (referred to as "other inorganic fillers") having a thermal conductivity of less than 2 [W / (m·K)] or more than 12 [W / (m·K)], other than the (c) inorganic filler. When the resin composition contains other inorganic fillers, the amount of the other inorganic fillers may be, for example, such that the average thermal conductivity of the (c) inorganic filler and the other inorganic fillers is 2 to 12 [W / (m·K)].

[0066] The content of the (c) inorganic filler in the resin composition of this embodiment is 5 to 50 parts by mass, preferably 5 to 45 parts by mass, and more preferably 10 to 40 parts by mass, relative to 100 parts by mass of the (a) resin component, from the viewpoint of achieving a sufficiently good balance between processability, heat resistance, tracking resistance, and rigidity. In one embodiment, the content of the (c) component is 5 parts by mass or more, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, 25 parts by mass or more, 30 parts by mass or more, 35 parts by mass or more, 40 parts by mass or more, or 45 parts by mass or more, relative to 100 parts by mass of the (a) component. In another embodiment, the content of the (c) component is 50 parts by mass or less, 45 parts by mass or less, 40 parts by mass or less, 35 parts by mass or less, 30 parts by mass or less, 25 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, or 10 parts by mass or less, relative to 100 parts by mass of the (a) component.

[0067] [Mass ratio of component (b) to component (c)] In this embodiment, the mass ratio ((b) / (c)) of the (b) component to the (c) component is 0.2 to 8.0. It is presumed that this mass ratio improves tracking resistance by trapping electric charge and stabilizing space charge due to potential wells generated by the (b) component dispersed in the resin when a voltage is applied. It is also considered that a ratio of 0.2 to 8.0 with respect to the (c) component makes it possible to achieve a high level of both tracking resistance and rigidity. The reason for this is that it is considered that the rigidity improving effect of the (c) component is exerted while the decrease in tracking resistance due to the carbonized conductive path formed by the (c) component is appropriately suppressed.

[0068] In one embodiment, the mass ratio ((b) / (c)) is 0.20 or more, 0.50 or more, 0.60 or more, 0.65 or more, 0.70 or more, 0.80 or more, 0.90 or more, 1.00 or more, 1.10 or more, 1.20 or more, 1.30 or more, 1.40 or more, 1.50 or more, 1.60 or more, 1.70 or more, 1.80 or more, 1.90 or more, 2.00 or more, 2.50 or more, 3.00 or more, 3.30 or more, 3.50 or more, 4.00 or more, 4.50 or more, 5.00 or more, 5.50 or more, 6.00 or more, 6.50 or more, 7.00 or more, or 7.50 or more. In another embodiment, the mass ratio ((b) / (c)) is 8.00 or less, 7.50 or less, 7.00 or less, 6.50 or less, 6.00 or less, 5.50 or less, 5.00 or less, 4.50 or less, 4.00 or less, 3.50 or less, 3.00 or less, 2.50 or less, 2.00 or less, 1.90 or less, 1.80 or less, 1.70 or less, 1.60 or less, 1.50 or less, 1.40 or less, 1.30 or less, 1.20 or less, 1.10 or less, 1.00 or less, 0.65 or less, or 0.50 or less. The mass ratio ((b) / (c)) is preferably 0.5 to 5.0, more preferably 0.6 to 4.0, and particularly preferably 0.65 to 3.5.

[0069] From the viewpoint of achieving a good balance between tracking resistance and rigidity, the total content of the (b) component and the (c) component is preferably 15 to 90 parts by mass, more preferably 20 to 80 parts by mass, and particularly preferably 20 to 75 parts by mass, per 100 parts by mass of the (a) resin component.

[0070] [(d) Phosphate-based flame retardants] The resin composition of the present embodiment may contain (d) a phosphate flame retardant. When the resin composition of the present embodiment contains (d) a phosphate flame retardant, the flame retardant-assisting effect of (a1) polyphenylene ether and the flame retardant-imparting effect of (d) the phosphate flame retardant are combined to provide a significant effect in imparting flame retardancy to the resin composition of the present embodiment.

[0071] As the (d) phosphoric acid ester-based flame retardant, a known phosphoric acid ester-based flame retardant can be used. As the (d) phosphoric acid ester-based flame retardant, for example, a phosphoric acid ester represented by the following general formula (1) and a condensate thereof can be mentioned. [ka] (1) In formula (1), R 1 , R 2 , R 3 and R 4 each represents any one selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aryl-substituted alkyl group, an aryl group, a halogen-substituted aryl group, and an alkyl-substituted aryl group, and may be the same or different. X represents an arylene group. n is an integer of 0, 1, 2, 3, 4, or 5. When n=0, the compound of formula (1) represents a phosphate monomer. When n is an integer of 1 to 5, the compound of formula (1) represents a phosphate condensate.

[0072] Representative phosphate monomers include, for example, triphenyl phosphate, tricresyl phosphate, and trixylenyl phosphate.

[0073] For condensates of phosphate esters, typically n can be 1, 2, 3, 4 or 5 on average, and preferably 1, 2 or 3 on average.

[0074] In addition, from the viewpoint of the flame retardancy and heat resistance exhibited when mixed with other resins, R 1 , R 2 , R 3 and R 4 It is preferable that at least one of R is an aryl group, and more preferable that R 1 , R 2 , R 3 and R 4 are all aryl groups. Aryl groups include, for example, phenyl, xylenyl, cresyl, or halogenated derivatives thereof.

[0075] Preferred examples of X include residues of resorcinol, hydroquinone, bisphenol A, biphenol, or halogenated derivatives thereof from which two hydroxyl groups have been eliminated.

[0076] Examples of the condensed phosphate ester compound include a resorcinol-bisphenyl phosphate compound, a bisphenol A-polyphenyl phosphate compound, and a bisphenol A-polycresyl phosphate compound.

[0077] (d) The phosphate ester-based flame retardants may be used alone or in combination of two or more.

[0078] The content of the (d) phosphate ester-based flame retardant may be adjusted as appropriate, but from the viewpoint of a balance between fluidity, heat resistance, and flame retardancy, it is, for example, 5 to 30 parts by mass, preferably 5 to 25 parts by mass, and more preferably 5 to 20 parts by mass, per 100 parts by mass of the (a) resin component.

[0079] [Other ingredients] The resin composition of the present embodiment may contain, in addition to the essential components (a1), (b), and (c) and the optional components (a2), (a3), and (d), other components as necessary within the range that does not impair the tracking resistance and rigidity of the polyphenylene ether resin composition.

[0080] Examples of other components include thermoplastic elastomers (polyolefin-based elastomers), heat stabilizers, antioxidants, metal deactivators, crystal nucleating agents, (d) flame retardants other than phosphate-based flame retardants (e.g., ammonium polyphosphate-based compounds, silicone-based flame retardants, etc.), plasticizers (e.g., low molecular weight polyethylene, epoxidized soybean oil, polyethylene glycol, fatty acid esters, etc.), weather resistance improvers, light resistance improvers, slip agents, organic fillers, organic reinforcing materials (e.g., polyacrylonitrile fibers, aramid fibers, etc.), colorants, and mold release agents.

[0081] The other components may be used alone or in combination of two or more.

[0082] [Method for producing resin composition] The resin composition of the present embodiment can be produced by melt-kneading the essential components and optional components. For example, the apparatus and conditions described in JP 2018-062608 A can be used.

[0083] As a specific method for producing the resin composition of this embodiment, it is preferable to use an extruder in which the oxygen concentration at each raw material supply port is controlled to less than 1.0 volume %, and to carry out the following method 1 or 2. 1. A manufacturing method comprising melt-kneading all or a part of the (a) and (b) components contained in the resin composition of this embodiment (first kneading step), and supplying the remaining components of the resin composition to the molten mixture obtained in the first kneading step and melt-kneading them (second kneading step). 2. A method of melt-kneading all of the components (a) to (d) contained in the resin composition of the present embodiment.

[0084] In the first kneading step and the second kneading step in the above 1, the kneaded product may be in a molten state, and the component (a1) may be melted once and pelletized, and then re-melted, thereby avoiding this.

[0085] [Molded product] The molded article of the present embodiment includes the polyphenylene ether resin composition of the present embodiment. The shape of the molded article of the present embodiment is not particularly limited, and examples thereof include a film shape, a sheet shape, and a box shape.

[0086] The manufacturing method of the molded product of this embodiment is not particularly limited, and a known manufacturing method of a molded product using a resin composition can be used.The manufacturing method of the molded product of this embodiment includes, for example, injection molding (for example, insert molding, hollow molding, multi-color molding, etc.), blow molding, compression molding, extrusion molding, thermoforming, and cutting processing from a thick plate.Among them, injection molding is preferred from the viewpoint of mass production.

[0087] In one embodiment, the molded article of the present embodiment is one or more selected from the group consisting of an injection molded article, a blow molded article, a compression molded article, an extrusion molded article, a thermoformed article, and an article cut from a thick plate, made of the polyphenylene ether resin composition of the present embodiment. In another embodiment, the molded article of the present embodiment is one or more selected from the group consisting of an insert molded article, a hollow molded article, and a multi-color molded article made of the polyphenylene ether resin composition of the present embodiment.

[0088] The flexural modulus is an index of the rigidity of the molded product. The flexural modulus of the molded product is not particularly limited, and is, for example, 2000 MPa or more, 2500 MPa or more, 3000 MPa or more, 3500 MPa or more, 4000 MPa or more, 4500 MPa or more, 5000 MPa or more, 5500 MPa or more, 6000 MPa or more, or 6500 MPa or more. The flexural modulus of the molded product is, for example, 8000 MPa or less, 7500 MPa or less, 7000 MPa or less, 6500 MPa or less, 6000 MPa or less, 5500 MPa or less, 5000 MPa or less, 4500 MPa or less, 4000 MPa or less, 3500 MPa or less, 3000 MPa or less, or 2500 MPa or less. In particular, when the flexural modulus is 3000 MPa or more, the molded product has a rigidity that can be applied to mechanical parts or structures.

[0089] [Application] The use of the resin composition of the present embodiment is not particularly limited. The resin composition of the present embodiment can be used in applications where tracking resistance and rigidity are important, and can be suitably used for electrical parts, electronic parts, and automotive electrical and electronic parts.

[0090] Applications of electrical components include, for example, office machines, measuring instruments, chassis, electrical equipment, power adapters, recording media, recording medium drives, sensor equipment, terminal blocks, secondary batteries, fuel cells, solar cells, generators, smart meters, power transmission equipment, cable terminals, automobiles, connection structures for photovoltaic power generation modules (module connectors, junction boxes, etc.), hybrid automobiles, and electric automobiles. EXAMPLES

[0091] Hereinafter, the present embodiment will be described with reference to specific examples and comparative examples, but the present embodiment is not limited to these.

[0092] Measurement method The measurement methods used in the examples and comparative examples are shown below.

[0093] Rigidity (flexural modulus) The obtained resin composition pellets were fed to a small injection molding machine (product name: EC75SXII, manufactured by Toshiba Machine Co., Ltd.) with a cylinder temperature set at 280°C, and molded under the conditions of a mold temperature of 80°C, an injection pressure of 120 MPa, an injection time of 15 seconds, and a cooling time of 20 seconds to produce an ISO dumbbell for evaluation. The flexural modulus (MPa) of this ISO dumbbell was measured according to ISO 178 to evaluate its rigidity. It was determined that the greater the flexural modulus value, the better the rigidity.

[0094] Tracking resistance (CTI) The obtained pellets of the resin composition were fed to a small injection molding machine (product name: EC75SXII, manufactured by Toshiba Machine Co., Ltd.) with a cylinder temperature set at 280°C, and molded into a flat plate of 70 mm x 70 mm x 3 mm under the conditions of a mold temperature of 80°C and an injection pressure of 120 MPa. The flat plate was measured for the maximum voltage (V) at which tracking breakdown did not occur according to IEC60112:2003 (electrolyte used: solution A, number of drops: 50 drops), and the tracking resistance was evaluated. It was determined that the higher the maximum voltage value, the better the tracking resistance.

[0095] The raw materials used in the examples and comparative examples are shown below.

[0096] (a1) Polyphenylene ether Poly(2,6-dimethyl-1,4-phenylene ether) "Product name: S201A manufactured by Asahi Kasei Corporation", reduced viscosity (0.5 g / dL chloroform solution, measured at 30°C, measured with an Ubbelohde type viscometer): 0.5 dL / g.

[0097] (a2) Polystyrene resin Polystyrene (Product name: Polystyrene 685 manufactured by PSJ) This is polystyrene that does not contain a rubber component, that is, polystyrene that is not rubber reinforced. High impact polystyrene (product name: CT60 manufactured by Petrochemicals)

[0098] (a3) Hydrogenated block copolymer ·SEBS “Product name: TAIPOL6151 Manufactured by TSRC”

[0099] (b) Titanium oxide Titanium oxide "Product name: TIOXIDE R-TC30 manufactured by Huntsman", average particle size (average primary particle size): 0.21 μm, crystal structure: rutile type

[0100] (c) Inorganic filler (c-1) Calcium silicate fibrous material: Wollastonite (product name: KTP-H02S, manufactured by Kansai Matec Co., Ltd.), thermal conductivity 2.7 [W / (m K)] (c-2) Talc "Product name: Crown Talc PK-MMB manufactured by Matsumura Sangyo Co., Ltd.", thermal conductivity 5.2 to 10.7 [W / (m K)]

[0101] Comparative inorganic filler (c'-1) Glass fiber "Product name: ECS03T-249, manufactured by Nippon Electric Glass Co., Ltd." Thermal conductivity 1.0 [W / (m K)] (c'-2) Mica "Product name: C-100IF manufactured by Repco" Thermal conductivity 0.67 [W / (m K)] (c'-3) Fibrous basic magnesium sulfate "Product name: MOS HIGE, manufactured by Ube Materials" Thermal conductivity 0.1 [W / (m K)]

[0102] (d) Phosphate-based flame retardants Aromatic condensed phosphate ester (product name: CR-741, manufactured by Daihachi Chemical Industry Co., Ltd.).

[0103] Example 1 A twin-screw extruder (ZSK-25: manufactured by Coperion) was used, with a first raw material supply port provided upstream of the raw material flow direction, a first vacuum vent, a second raw material supply port, and a third raw material supply port provided downstream of this, and a second vacuum vent provided further downstream. The cylinder temperature was set to 320°C on the upstream side and 300°C on the downstream side. According to the blending ratio (parts by mass) shown in Table 1, component (a) was supplied from the first supply port, component (b) from the second supply port, and component (c) from the third supply port. Liquid phosphate ester-based flame retardant (d) was supplied from a downstream pressure nozzle and melt-kneaded.

[0104] The screw speed was 200 rpm and the discharge rate was 15 kg / h. An opening (vent) was provided in the cylinder block, and the remaining volatile matter was removed by vacuum suction. The degree of vacuum (pressure) at this time was 0.09 MPa.

[0105] The strand extruded from the die was cooled and cut continuously with a cutter to obtain pellets of the resin composition of Example 1 having a length of about 3 mm and a diameter of 3 mm.

[0106] Examples 2 to 13 and Comparative Examples 1 to 6 The same procedure as in Example 1 was carried out except that the composition was changed as shown in Tables 1 to 3, to obtain resin pellets.

[0107] The obtained resin composition pellets were used to evaluate the rigidity and tracking resistance, and the evaluation results are shown in Tables 1 to 3 below.

[0108] [Table 1]

[0109] [Table 2]

[0110] [Table 3] [Industrial Applicability]

[0111] According to the present invention, it is possible to provide a resin composition which is capable of giving a molded article having excellent tracking resistance and imparted rigidity.

Claims

1. (a) a resin component; (b) titanium oxide; (c) an inorganic filler; (d) a phosphate ester flame retardant; and Including, The (c) inorganic filler has a thermal conductivity of 2 to 12 [W / (m K)], The (a) resin component contains 50 to 90 parts by mass of (a1) polyphenylene ether per 100 parts by mass of the (a) resin component, the amount of the (b) titanium oxide is 5 to 40 parts by mass relative to 100 parts by mass of the (a) resin component, the amount of the (c) inorganic filler is 5 to 35 parts by mass relative to 100 parts by mass of the (a) resin component, The mass ratio ((b) / (c)) of the (b) titanium oxide to the (c) inorganic filler is 0.2 to 8.0; and The polyphenylene ether resin composition, wherein the amount of the (d) phosphate ester-based flame retardant is 5 to 30 parts by mass per 100 parts by mass of the (a) resin component.

2. 2. The polyphenylene ether resin composition according to claim 1, wherein the inorganic filler (c) is at least one selected from the group consisting of calcium silicate fibrous material (c-1) and talc (c-2).

3. 3. The polyphenylene ether resin composition according to claim 2, wherein the (c) inorganic filler is the (c-1) calcium silicate-based fibrous material.

4. 3. The polyphenylene ether resin composition according to claim 2, wherein the calcium silicate fibrous material (c-1) is wollastonite.

5. The polyphenylene ether resin composition according to any one of claims 1 to 4, wherein a total content of the (b) titanium oxide and the (c) inorganic filler is 15 to 75 parts by mass per 100 parts by mass of the (a) resin component.

6. The polyphenylene ether resin composition according to any one of claims 1 to 5, wherein the (a) resin component contains 1 to 49 parts by mass of an (a2) polystyrene-based resin per 100 parts by mass of the (a) resin component.

7. The polyphenylene ether resin composition according to any one of claims 1 to 6, wherein the (a) resin component contains 1 to 49 parts by mass of the (a3) ​​hydrogenated block copolymer per 100 parts by mass of the (a) resin component.

8. 2. The polyphenylene ether resin composition according to claim 1, wherein the (d) phosphate ester-based flame retardant is a condensate of a phosphate ester.

9. A molded article comprising the polyphenylene ether resin composition according to any one of claims 1 to 8.

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