Thermoplastic elastomer composition

Abstract

To provide a thermoplastic elastomer composition excellent in moldability.SOLUTION: (A) an ethylene-propylene-nonconjugated polyene copolymerized elastomer, (B) a polypropylene, (C) a hydrogenated product of a block polymer of an aromatic vinyl compound and a conjugated diene compound, and (E) a phenolic resin crosslinking agent, wherein the polypropylene (B) comprises a (0g) polypropylene having a melt mass flow rate of 0.1 to 3 B1 / 10 minutes and a (0g) polypropylene having a melt mass flow rate of more than 3 100g / 10 minutes and not more than B2 / 10 minutes. Preferably, the composition further contains (D) a non-aromatic rubber softener and (F) talc.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a thermoplastic elastomer composition. [Background technology]

[0002] Polyolefin-based thermoplastic elastomer compositions, obtained by melt-kneading a polyolefin (e.g., polypropylene) and an ethylene-propylene-non-conjugated polyene copolymer elastomer (e.g., EPDM) in the presence of a crosslinking agent such as a phenolic resin, have been widely used in various thermoplastic elastomer products for automotive, industrial, and construction applications due to their low specific gravity (allowing for lightweight products), ease of recycling, and excellent heat, aging, ozone, and weather resistance. However, polyolefin-based thermoplastic elastomer compositions have drawbacks, such as insufficient flexibility due to the high polypropylene content, and poor moldability due to the crosslinking of the ethylene-propylene-non-conjugated polyene copolymer elastomer with a phenolic resin, particularly when the polypropylene content is reduced to increase flexibility. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-002085 [Patent Document 2] International Publication No. 2018 / 181106 [Patent Document 3] Japanese Patent Application Laid-Open No. 2009-275213 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a thermoplastic elastomer composition that is excellent in moldability. [Means for solving the problem]

[0005] As a result of extensive research, the present inventors have found that the above object can be achieved by a specific composition.

[0006] That is, the various aspects of the present invention are as follows. [1]. (A) 100 parts by mass of ethylene-propylene-non-conjugated polyene copolymer elastomer, (B) 5 to 250 parts by mass of polypropylene, (C) 5 to 120 parts by mass of a hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound, (D) 0 to 500 parts by mass of a non-aromatic rubber softener, and (E) 0.5 to 25 parts by mass of a phenolic resin crosslinking agent, wherein the component (B) polypropylene is (B1) Polypropylene having a melt mass flow rate of 0.1 to 3.0 g / 10 min measured at a temperature of 230°C and a load of 21.18 N in accordance with JIS K7210-1:2014. (B2) Comprised of polypropylene having a melt mass flow rate of more than 3.0 g / 10 min and less than 100 g / 10 min, measured at a temperature of 230 ° C and a load of 21.18 N in accordance with JIS K7210-1:2014; Thermoplastic elastomer composition. [2]. The thermoplastic elastomer composition according to item [1], further comprising 1 to 100 parts by mass of (F) talc per 100 parts by mass of the component (A) ethylene-propylene-non-conjugated polyene copolymer elastomer. [3]. The thermoplastic elastomer composition according to item [1] or [2], wherein the mass ratio of the blended amount of the component (B1) polypropylene to the blended amount of the component (B2) polypropylene (blended amount of the component (B1) / blended amount of the component (B2)) is 98 / 2 to 5 / 95. [4]. The thermoplastic elastomer composition according to any one of items [1] to [3], wherein the component (B1) polypropylene contains a copolymer of propylene with one or more other α-olefins. [5]. The thermoplastic elastomer composition according to any one of items [1] to [4], wherein the component (B2) polypropylene contains a copolymer of propylene with one or more other α-olefins. [6]. The thermoplastic elastomer composition according to any one of items [1] to [5], wherein the amount of the non-aromatic rubber softener (component (D)) blended is 140 to 400 parts by mass. [7]. The thermoplastic elastomer composition according to any one of items [1] to [6], wherein the component (C), a hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound, comprises a hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound, the hydrogenated product having a structural unit derived from β-farnesene. [8]. An article comprising the thermoplastic elastomer composition according to any one of items [1] to [7]. [9]. An article in which the thermoplastic elastomer composition according to any one of items [1] to [7] is laminated on the surface of a metal or resin core material. [Effects of the Invention]

[0007] The thermoplastic elastomer composition of the present invention has excellent moldability. A preferred thermoplastic elastomer composition of the present invention also has good flexibility and compression set resistance. Therefore, the thermoplastic elastomer composition of the present invention can be suitably used in various thermoplastic elastomer products for automobiles, industrial applications, construction, and the like. DETAILED DESCRIPTION OF THE INVENTION

[0008] In this specification, the term "resin" is used to include a resin mixture containing two or more resins and a resin composition containing components other than resin. The same applies to the term "elastomer."

[0009] In this specification, the term "more than or equal to" in relation to a numerical range means a certain number or more than a certain number. For example, 20% or more means 20% or more than 20%. The term "less than or equal to" in relation to a numerical range means a certain number or less than a certain number. For example, 20% or less means 20% or less than 20%. Furthermore, the symbol "to" in relation to a numerical range means a certain number, more than a certain number and less than another certain number, or another certain number. Here, another certain number is a number greater than the certain number. For example, 10 to 90% means 10%, more than 10% and less than 90%, or 90%. Furthermore, the upper and lower limits of a numerical range can be arbitrarily combined, and embodiments incorporating such combinations can be interpreted. For example, from a statement regarding the numerical range of a certain characteristic such as "usually 10% or more, preferably 20% or more. On the other hand, it is usually 40% or less, preferably 30% or less," or "usually 10 to 40%, preferably 20 to 30%," it can be read that the numerical range of the certain characteristic is 10 to 40%, 20 to 30%, 10 to 30%, or 20 to 40% in one embodiment.

[0010] Other than in the examples, or where otherwise specified, all numerical values ​​used in the specification and claims should be understood to be modified by the term "about." Without attempting to limit the application of the doctrine of equivalents to the claims, each numerical value should be construed in light of the number of significant digits and by applying ordinary rounding techniques.

[0011] In this specification, terms specifying shapes or geometric conditions, such as parallel, orthogonal, and perpendicular, are intended to include not only the strict meanings but also substantially the same states.

[0012] In this specification, when it is explained that "comprises a certain substance," it is to be understood that, in one embodiment, it contains a certain substance, consists of a certain substance, or consists only of a certain substance. For example, from the explanation that "composition A comprises substances a1 and a2," it is to be understood that, in one embodiment, composition A comprises substances a1 and a2, composition A consists of substances a1 and a2, or composition A consists only of substances a1 and a2.

[0013] 1. Thermoplastic elastomer composition: The thermoplastic elastomer composition of the present invention comprises (A) an ethylene-propylene-non-conjugated polyene copolymer elastomer, (B) polypropylene, (C) a hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound, and (E) a phenolic resin crosslinking agent. In one preferred embodiment, the thermoplastic elastomer composition of the present invention may further comprise (D) a non-aromatic rubber softener. In another preferred embodiment, the thermoplastic elastomer composition of the present invention may further comprise (F) talc. Each component is described below.

[0014] (A) Ethylene-propylene-non-conjugated polyene copolymer elastomer: The thermoplastic elastomer composition of the present invention contains the above-mentioned component (A), an ethylene-propylene-non-conjugated polyene copolymer elastomer. The component (A) is a copolymer of ethylene, propylene, and a non-conjugated polyene, and has elastomeric properties, which impart flexibility to the thermoplastic elastomer composition of the present invention.

[0015] Examples of the non-conjugated polyenes include 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 1,7-octadiene, bicyclo[2.2.1]hepta-2-ene (norbornene), 5-ethylidene-2-norbornene (ethylidenenorbornene), and tricyclo[4.3.0.12,5]deca-3,7-diene (dicyclopentadiene), as well as non-conjugated trienes such as 1,3,7-octatriene, 1,5,9-decatriene, (Z)-4-ethylidene-8-methyl-1,7-nonadiene, and bicyclo[2.2.1]hepta-2,5-diene. One or more of these can be used as the non-conjugated polyene.

[0016] From the viewpoint of efficiently carrying out modification with the phenolic resin crosslinking agent (Component (E)), the ethylene-propylene-non-conjugated polyene copolymer elastomer may preferably contain an ethylene-propylene-non-conjugated diene copolymer elastomer, and more preferably may contain a copolymer elastomer of ethylene, propylene, and one or more dienes selected from the group consisting of 5-ethylidene-2-norbornene (ethylidene norbornene), tricyclo[4.3.0.12,5]deca-3,7-diene (dicyclopentadiene), and 1,4-hexadiene.

[0017] From the viewpoint of flexibility, the ethylene-propylene-non-conjugated polyene copolymer elastomer as component (A) may preferably be one polymerized using a metallocene catalyst.

[0018] The Mooney viscosity (ML) of the above component (A) ethylene-propylene-non-conjugated polyene copolymer elastomer was measured in accordance with ASTM D1646 using an L-shaped rotor under the conditions of a preheating time of 1 minute, a rotor rotation time of 4 minutes, and a test temperature of 125°C. 1+4 125°C) may be preferably 5 to 150, more preferably 20 to 120, and even more preferably 40 to 100, from the viewpoint of moldability and compression set characteristics.

[0019] The content of structural units derived from non-conjugated polyene in the component (A) ethylene-propylene-non-conjugated polyene copolymer elastomer may be preferably 0.1 to 10 mass %, more preferably 1 to 8 mass %, and even more preferably 3 to 7 mass %, from the viewpoints of moldability and efficient modification with the component (E) phenolic resin crosslinking agent.

[0020] The content of ethylene-derived structural units in the ethylene-propylene-non-conjugated polyene copolymer elastomer (component (A))) may be preferably 40 to 90% by mass, more preferably 50 to 80% by mass, and even more preferably 60 to 75% by mass, from the viewpoints of flexibility and mechanical strength.

[0021] The ethylene-propylene-non-conjugated polyene copolymer elastomer (component (A)) may contain structural units derived from monomers other than ethylene, propylene, and non-conjugated polyenes (hereinafter referred to as "other monomers"), provided that the object of the present invention is not violated.

[0022] Examples of the other monomers include α-olefins other than ethylene and propylene, such as 1-butene, 1-hexene, and 1-octene; conjugated dienes, such as 1,3-butadiene and isoprene (2-methyl-1,3-butadiene); unsaturated carboxylic acids, such as (meth)acrylic acid; alkyl (meth)acrylate esters, such as methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate; acid anhydrides of unsaturated carboxylic acids, such as maleic anhydride; aromatic vinyl compounds, such as styrene; and compounds having a polymerizable carbon-carbon double bond, such as vinyl acetate. As the other monomers, one or more of these can be used.

[0023] The content of the structural units derived from the other monomers in component (A) may be 10% by mass or less, 5% by mass or less, 3% by mass or less, 1% by mass or less, 0 to 1% by mass, or 0.01 to 10% by mass, with the sum of all structural units in component (A) being 100% by mass.

[0024] In one embodiment, the ethylene-propylene-non-conjugated polyene copolymer elastomer (component (A))) may be free of any of the other monomers described above. Here, "free of any of the other monomers described above" means that the other monomers are not intentionally used. Therefore, "free of any of the other monomers described above" can be rephrased as meaning that the content of structural units derived from the other monomers in component (A) is typically 0.1% by mass or less, preferably 0.05% by mass or less, and more preferably 0 to 0.01% by mass.

[0025] As the component (A), the ethylene-propylene-non-conjugated polyene copolymer elastomer, one or more of these can be used.

[0026] (B) Polypropylene: The thermoplastic elastomer composition of the present invention contains the above-mentioned component (B) polypropylene. The component (B) polypropylene consists of a polypropylene with a relatively high molecular weight (low melt mass-flow rate) and a polypropylene with a relatively low molecular weight (high melt mass-flow rate). Specifically, the component (B) polypropylene consists of (B1) a polypropylene having a melt mass-flow rate of 0.1 to 3.0 g / 10 min, measured in accordance with JIS K7210-1:2014 at 230°C and a load of 21.18 N, and (B2) a polypropylene having a melt mass-flow rate of more than 3.0 g / 10 min and not more than 100 g / 10 min, measured in accordance with JIS K7210-1:2014 at 230°C and a load of 21.18 N.

[0027] The thermoplastic elastomer composition of the present invention contains the above-mentioned component (B1) polypropylene and the above-mentioned component (B2) polypropylene, and therefore exhibits sufficient moldability even when the amount of polypropylene blended is reduced to increase flexibility.

[0028] Without intending to be bound by theory, the reason why the thermoplastic elastomer composition of the present invention, which contains the above-mentioned component (B1) polypropylene and the above-mentioned component (B2) polypropylene, exhibits sufficient moldability even when the amount of polypropylene is reduced to enhance flexibility, is considered to be as follows: When a polypropylene with a high molecular weight (low melt mass-flow rate) is used alone, the high molecular weight results in high shear stress until the composition is extruded from a die or injected into a mold, which (high shear stress) can easily cause molding defects. On the other hand, when a polypropylene with a low molecular weight (high melt mass-flow rate) is used alone, its low molecular weight and high molecular mobility easily cause phase separation between the component (A) ethylene-propylene-non-conjugated polyene copolymer elastomer and the component (C) hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound during the cooling and solidification process after extrusion from a die or injection into a mold, which (phase separation) can easily cause molding defects. In the present invention, since a polypropylene having a high molecular weight and a polypropylene having a low molecular weight are used in combination, it is possible to suppress both molding defects caused by high shear stress and molding defects caused by phase separation.

[0029] The component (B1) polypropylene will now be described. The component (B1) polypropylene is a resin that contains primarily structural units derived from propylene and has a melt mass flow rate of 0.1 to 3.0 g / 10 min, as measured in accordance with JIS K7210-1:2014 at a temperature of 230°C and a load of 21.18 N. Here, "containing primarily structural units derived from propylene" means that the content of structural units derived from propylene is 50 to 100 mol %.

[0030] The melt mass flow rate of the polypropylene component (B1), measured in accordance with JIS K7210-1:2014 at a temperature of 230°C and a load of 21.18 N, may be preferably 0.5 to 2.5 g / 10 min, more preferably 1.0 to 2.0 g / 10 min, from the viewpoint of moldability.

[0031] From the viewpoints of heat resistance and oil resistance, the polypropylene component (B1) may have a melting enthalpy measured by the method described below of preferably 50 J / g or more, more preferably 60 J / g or more, even more preferably 70 J / g or more, and still more preferably 75 J / g or more. From the viewpoint of flexibility, the polypropylene component (B1) may have a melting enthalpy of preferably 115 J / g or less, more preferably 110 J / g or less, even more preferably 105 J / g or less, and still more preferably 100 J / g or less.

[0032] From the viewpoints of heat resistance and oil resistance, the polypropylene component (B1) may have a melting point, measured by the method described below, of preferably 130° C. or higher, more preferably 140° C. or higher, even more preferably 150° C. or higher, and still more preferably 160° C. or higher. From the viewpoints of heat resistance and solvent resistance, the melting point of the polypropylene component (B1) is preferably higher.

[0033] In this specification, the melting point and melting enthalpy of polypropylene are calculated from a DSC second melting curve (the melting curve measured during the final heating process) measured using a differential scanning calorimeter (DSC) in accordance with JIS K7121-1987, using a program that involves holding at 230°C for 5 minutes, cooling to -50°C at 10°C / min, holding at -50°C for 5 minutes, and then heating to 230°C at 10°C / min. The melting point is the peak-top temperature of the melting peak that appears in the second melting curve. When two or more melting peaks are observed, the melting point is the peak-top temperature of the melting peak with the greatest peak-top height. Figure 1 shows a measurement example. The lower curve in Figure 1 is the DSC second melting curve, and the upper curve is the DSC crystallization curve. It should be noted that the melting peak appearing in the DSC second melting curve of polypropylene usually has a long, gradual base on the low-temperature side; and that the baseline should be drawn so that the line extending from the high-temperature side baseline to the low-temperature side in Figure 1 of JIS K7121-1987, Section 9. How to read DTA or DSC curves, coincides with the line extending from the same low-temperature side baseline to the high-temperature side.

[0034] Examples of polypropylenes having the above-described properties that can be used as the component (B1) polypropylene include isotactic polypropylenes such as propylene homopolymers and copolymers (including block copolymers and random copolymers) of propylene with one or more other α-olefins (e.g., ethylene, 1-butene, 1-hexene, 1-octene, and 4-methyl-1-pentene).

[0035] Among these, the polypropylene component (B1) may preferably contain a copolymer of propylene with one or more other α-olefins, from the viewpoint of improving compatibility with the ethylene-propylene-non-conjugated polyene copolymer elastomer component (A) and the hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound component (C) and suppressing phase separation. In this case, the content of structural units derived from the α-olefin in the copolymer of propylene with one or more other α-olefins may be preferably 1 to 50 mol % (50 to 99 mol % of structural units derived from propylene), more preferably 2 to 40 mol % (60 to 98 mol % of structural units derived from propylene), even more preferably 3 to 30 mol % or less (70 to 97 mol % of structural units derived from propylene), and even more preferably 5 to 25 mol % (75 to 95 mol % of structural units derived from propylene).

[0036] As the component (B1) polypropylene, one or more of these can be used.

[0037] The component (B2) polypropylene will now be described. The component (B2) polypropylene is a resin that primarily contains structural units derived from propylene and has a melt mass flow rate of more than 3.0 g / 10 min and not more than 100 g / 10 min, as measured in accordance with JIS K7210-1:2014 at a temperature of 230°C and a load of 21.18 N. Here, "primarily containing structural units derived from propylene" means that the content of structural units derived from propylene is 50 to 100 mol%.

[0038] The melt mass flow rate of the polypropylene component (B2), measured in accordance with JIS K7210-1:2014 at a temperature of 230°C and a load of 21.18 N, may be preferably 4.0 to 80 g / 10 min, more preferably 5.0 to 60 g / 10 min, and even more preferably 6.0 to 50 g / 10 min, from the viewpoint of moldability.

[0039] From the viewpoints of heat resistance and oil resistance, the polypropylene component (B2) may have a melting enthalpy measured by the above-mentioned method of preferably 50 J / g or more, more preferably 60 J / g or more, even more preferably 70 J / g or more, and still more preferably 75 J / g or more. From the viewpoint of flexibility, the polypropylene component (B2) may have a melting enthalpy of preferably 115 J / g or less, more preferably 110 J / g or less, even more preferably 105 J / g or less, and still more preferably 100 J / g or less.

[0040] From the viewpoints of heat resistance and oil resistance, the melting point of the polypropylene component (B1), measured by the above-mentioned method, may be preferably 130° C. or higher, more preferably 140° C. or higher, even more preferably 150° C. or higher, and even more preferably 160° C. or higher. From the viewpoints of heat resistance and oil resistance, the melting point of the polypropylene component (B2) is preferably higher.

[0041] Examples of polypropylenes having the above-described properties that can be used as the component (B2) polypropylene include isotactic polypropylenes such as propylene homopolymers and copolymers (including block copolymers and random copolymers) of propylene with one or more other α-olefins (e.g., ethylene, 1-butene, 1-hexene, 1-octene, and 4-methyl-1-pentene).

[0042] Among these, the polypropylene component (B2) may preferably contain a copolymer of propylene with one or more other α-olefins, from the viewpoint of improving compatibility with the ethylene-propylene-non-conjugated polyene copolymer elastomer component (A) and the hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound component (C) and suppressing phase separation. In this case, the content of structural units derived from the α-olefin in the copolymer of propylene with one or more other α-olefins may be preferably 1 to 50 mol % (50 to 99 mol % of structural units derived from propylene), more preferably 2 to 40 mol % (60 to 98 mol % of structural units derived from propylene), even more preferably 3 to 30 mol % or less (70 to 97 mol % of structural units derived from propylene), and even more preferably 5 to 25 mol % (75 to 95 mol % of structural units derived from propylene).

[0043] As the component (B2) polypropylene, one or more of these can be used.

[0044] The amount of the polypropylene component (B) (the sum of the amount of the polypropylene component (B1) and the amount of the polypropylene component (B2)) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and even more preferably 15 parts by mass or more, per 100 parts by mass of the ethylene-propylene-non-conjugated polyene copolymer elastomer component (A), from the viewpoint of moldability. On the other hand, the amount of the polypropylene component (B), from the viewpoint of flexibility, is usually 250 parts by mass or less, preferably 150 parts by mass or less, more preferably 80 parts by mass or less, even more preferably 50 parts by mass or less, even more preferably 30 parts by mass or less, and most preferably 25 parts by mass or less.

[0045] The mass ratio of the amount of the polypropylene component (B1) to the amount of the polypropylene component (B2) (amount of the component (B1) / amount of the component (B2)) may be preferably 98 / 2 to 5 / 95, more preferably 90 / 10 to 20 / 80, even more preferably 85 / 15 to 40 / 60, and still more preferably 80 / 20 to 50 / 50.

[0046] (C) Hydrogenated block copolymer of aromatic vinyl compound and conjugated diene compound: The thermoplastic elastomer composition of the present invention contains the above-mentioned component (C), a hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound. The above-mentioned component (C), a hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound, serves to suppress bleed-out of the above-mentioned component (D), a non-aromatic rubber softener. Furthermore, the above-mentioned component (C), a hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound, serves to improve flexibility and moldability.

[0047] The hydrogenated block copolymer of component (C) an aromatic vinyl compound and a conjugated diene compound is a substance obtained by adding hydrogen to a block polymer containing one or more aromatic vinyl compound polymer segments (c1) and one or more conjugated diene compound polymer segments (c2), thereby converting some or all of the carbon-carbon double bonds in the block polymer into carbon-carbon single bonds. Examples of the hydrogenated block copolymer of component (C) an aromatic vinyl compound and a conjugated diene compound include those having segment structures such as (c1)-(c2), (c1)-(c2)-(c1), (c2)-(c1)-(c2), (c1)-(c2)-(c1)-(c2), and (c1)-(c2)-(c1)-(c2)-(c1).

[0048] The aromatic vinyl compound is a polymerizable monomer having a polymerizable carbon-carbon double bond and an aromatic ring. Examples of the aromatic vinyl compound include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N,N-diethyl-p-aminoethylstyrene, vinyltoluene, and p-tert-butylstyrene. The aromatic vinyl compound may preferably contain styrene. One or more of these compounds may be used as the aromatic vinyl compound.

[0049] The conjugated diene compound is a polymerizable monomer having a structure in which two carbon-carbon double bonds are bonded by one carbon-carbon single bond. Examples of the conjugated diene compound include 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 1,3-octadiene, 1,3-cyclohexadiene, 2-methyl-1,3-octadiene, 1,3,7-octatriene, 7-methyl-3-methyleneocta-1,6-diene (β-myrcene), 3,7,11-trimethyl-1,3,6,10-dodecatetraene (α-farnesene), 7,11-dimethyl-3-methylene-1,6,10-dodecatriene (β-farnesene), and chloroprene (2-chloro-1,3-butadiene). The conjugated diene compound may preferably contain one or more selected from the group consisting of 1,3-butadiene, isoprene, β-myrcene, α-farnesene, and β-farnesene, and one or more of these can be used as the conjugated diene compound.

[0050] The (c1) aromatic vinyl compound polymer segment is a polymer segment mainly containing structural units derived from the aromatic vinyl compound. Here, "mainly containing" means that the content of structural units derived from the aromatic vinyl compound is 60 to 100% by mass. From the viewpoint of heat resistance, the content of structural units derived from the aromatic vinyl compound may be preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, still more preferably 95% by mass or more, and most preferably 99 to 100% by mass.

[0051] Examples of the (c1) aromatic vinyl compound polymer segment include a homopolymer segment of the aromatic vinyl compound, a copolymer segment of the aromatic vinyl compound and the conjugated diene compound, etc. When there are two or more (c1) aromatic vinyl compound polymer segments, they may have the same structure or different structures.

[0052] The (c2) conjugated diene compound polymer segment is a polymer segment mainly containing structural units derived from the conjugated diene compound. Here, "mainly containing" means that the content of structural units derived from the conjugated diene compound is 60 to 100% by mass. From the viewpoint of flexibility, the content of structural units derived from the conjugated diene compound may be preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, still more preferably 95% by mass or more, and most preferably 99 to 100% by mass.

[0053] Examples of the (c2) conjugated diene compound polymer segment include a homopolymer segment of the conjugated diene compound, a copolymer segment of the conjugated diene compound and the aromatic vinyl compound, etc. When there are two or more (c2) conjugated diene compound polymer segments, they may have the same structure or different structures.

[0054] The hydrogenation rate of the hydrogenated product of the block copolymer of the aromatic vinyl compound and the conjugated diene compound (component (C)) (the ratio of the number of carbon-carbon single bonds resulting from hydrogenation to the number of carbon-carbon double bonds in the block copolymer of the aromatic vinyl compound and the conjugated diene compound before hydrogenation) may be, from the viewpoint of heat resistance, usually 50 mol % or more, preferably 60 mol % or more, more preferably 70 mol % or more, even more preferably 80 mol % or more, and most preferably 90 to 100 mol %.

[0055] The content of structural units derived from the aromatic vinyl compound in the hydrogenated block copolymer of component (C) an aromatic vinyl compound and a conjugated diene compound may be preferably 5 to 60% by mass, more preferably 10 to 50% by mass, and even more preferably 20 to 40% by mass, from the viewpoints of flexibility and heat resistance.

[0056] The mass average molecular weight (Mw) of the hydrogenated block copolymer of the aromatic vinyl compound and the conjugated diene compound (C) is preferably 1.5×10 in terms of polystyrene, as determined from the differential molecular weight distribution curve (hereinafter sometimes abbreviated as "GPC curve") measured by gel permeation chromatography (hereinafter sometimes abbreviated as "GPC"), from the viewpoint of tensile properties. 4 More preferably, 4.5 × 10 4 More preferably, 1.5 × 10 5 On the other hand, from the viewpoint of moldability, the mass average molecular weight (Mw) is preferably 1.5 × 10 6 Less than or equal to 1.2 × 10 6 It may be the following:

[0057] The number average molecular weight (Mn) of the hydrogenated block copolymer of the component (C), an aromatic vinyl compound and a conjugated diene compound, calculated as polystyrene from the GPC curve is preferably 1.0×10 4 More preferably, 3.0 × 10 4 More preferably, 1.0 × 10 5 On the other hand, the number average molecular weight (Mn) is preferably 1.0 × 10 or more from the viewpoint of moldability.6 More preferably, it may be 8.0×10 5 or less.

[0058] The GPC measurement of the hydrogenated product of the block copolymer of the above component (C) aromatic vinyl compound and conjugated diene compound is carried out using the high-performance liquid chromatography system "HLC-8320 (trade name)" of Tosoh Corporation (a system including a degasser, a liquid delivery pump, an autosampler, a column oven, and a RI (differential refractive index) detector) as a system. As GPC columns, two "KF-806L (trade name)" of Shodex, one "KF-802 (trade name)", and one "KF-801 (trade name)" are used in total. A total of 4 columns are connected in series in the order of KF-806L, KF-806L, KF-802, and KF-801 from the upstream side and used. Tetrahydrofuran (excluding stabilizer) is used as the mobile phase, and it can be carried out under the conditions of a column temperature of 40°C, a flow rate of 1.0 mL / min, a sample concentration of 1 mg / mL, and a sample injection volume of 100 μL. The elution volume at each retention volume can be obtained from the detection amount of the RI detector on the assumption that there is no molecular weight dependence on the refractive index of the measurement sample. The calibration curve from each retention volume to the polystyrene-equivalent molecular weight can be created using standard polystyrene. At this time, it should be noted that the standard polystyrene to be used should be appropriately selected so that the retention volume of the measurement sample is interpolated into the plot of the calibration curve. For the theory and practice of GPC, reference can be made to reference books such as "Size Exclusion Chromatography High-Performance Liquid Chromatography of Polymers, Author: Sadao Mori, First Edition, First Printing, December 10, 1991" by Kyoritsu Shuppan Co., Ltd., and "Synthetic Polymer Chromatography, Editors: Hajime Ohtani, Tatsuya Takasaki (the upper part of '崎' is '立'), First Edition, First Printing, July 25, 2013" by Ohmsha, Ltd.

[0059] Examples of component (C), hydrogenated block copolymers of aromatic vinyl compounds and conjugated diene compounds, include styrene-ethylene-butene block copolymer (SEB), styrene-ethylene-propylene block copolymer (SEP), styrene-ethylene-butene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS), styrene-butadiene-butylene-styrene copolymer (partially hydrogenated styrene-butadiene-styrene copolymer: SBBS), partially hydrogenated styrene-isoprene-styrene copolymer, partially hydrogenated styrene-isoprene-butadiene-styrene copolymer, and hydrogenated styrene-β-farnesene block copolymer.

[0060] In one embodiment, the component (C) hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound may include a hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound having structural units derived from β-farnesene, such as the hydrogenated styrene-β-farnesene block copolymer. β-Farnesene is obtained by fermenting sugars from sugarcane, which reduces the environmental impact. Furthermore, the inclusion of structural units derived from β-farnesene can enhance flexibility.

[0061] As the component (C), a hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound, one or more of these can be used.

[0062] The blending amount of the component (C) hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound may be, relative to 100 parts by mass of the component (A) ethylene-propylene-non-conjugated polyene copolymer elastomer, preferably 5 parts by mass or more, more preferably 10 parts by mass or more, even more preferably 15 parts by mass or more, still more preferably 20 parts by mass or more, and most preferably 25 parts by mass or more, from the viewpoint of suppressing bleed-out of the component (D) non-aromatic rubber softener and improving flexibility and moldability. On the other hand, the blending amount of the component (C) hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound may be, from the viewpoint of oil resistance, preferably 120 parts by mass or less, more preferably 100 parts by mass or less, and even more preferably 80 parts by mass or less.

[0063] (D) Non-aromatic rubber softeners: In one preferred embodiment, the thermoplastic elastomer composition of the present invention may further contain the non-aromatic rubber softener (Component (D)), which acts to increase flexibility and suppress molding defects caused by high shear stress.

[0064] The non-aromatic rubber softener (component (D)) is a non-aromatic mineral oil (a hydrocarbon compound derived from petroleum, etc.) or synthetic oil (synthetic hydrocarbon compound). Here, "non-aromatic" means that, for mineral oils, they are not classified as aromatic (the number of aromatic carbon atoms is less than 30%). For synthetic oils, this means that they do not contain aromatic monomers.

[0065] Mineral oils used as rubber softeners are mixtures of one or more of paraffin chains, naphthenic rings, and aromatic rings. They are classified as follows: those with 30 to 45% naphthenic ring carbon atoms are called naphthenic; those with 30% or more aromatic carbon atoms are called aromatic; and those that are neither naphthenic nor aromatic and have 50% or more paraffin chain carbon atoms are called paraffinic.

[0066] Examples of the non-aromatic rubber softener of component (D) include paraffinic mineral oils such as linear saturated hydrocarbons, branched saturated hydrocarbons, and derivatives thereof; naphthenic mineral oils; and synthetic oils such as hydrogenated polyisobutylene, polyisobutylene, and polybutene.

[0067] In one preferred embodiment, the non-aromatic rubber softener (Component (D)) may contain a paraffinic mineral oil, from the viewpoint of making it easier to retain by the hydrogenated block copolymer (Component (C)) of an aromatic vinyl compound and a conjugated diene compound and suppressing bleed-out. In this case, the paraffinic mineral oil may have an aromatic carbon number of preferably 20% or less, more preferably 10% or less, and even more preferably 0 to 5%.

[0068] As the component (D), the non-aromatic rubber softener, one or more of these can be used.

[0069] The amount of the non-aromatic rubber softener (component (D)) is an optional component and is not particularly limited as long as it does not interfere with the objectives of the present invention. To obtain a desired level of flexibility, the amount of the non-aromatic rubber softener (component (D)) may be 0 parts by mass or more, 20 parts by mass or more, 40 parts by mass or more, 60 parts by mass or more, 80 parts by mass or more, 100 parts by mass or more, 120 parts by mass or more, or 140 parts by mass or more per 100 parts by mass of the ethylene-propylene-non-conjugated polyene copolymer elastomer (component (A)). On the other hand, to suppress bleed-out, the amount of the non-aromatic rubber softener (component (D)) may be preferably 500 parts by mass or less, more preferably 450 parts by mass or less, even more preferably 400 parts by mass or less, and even more preferably 350 parts by mass or less.

[0070] (E) Phenolic resin crosslinker: The thermoplastic elastomer composition of the present invention contains the phenolic resin crosslinking agent (component (E)), which crosslinks the ethylene-propylene-non-conjugated polyene copolymer elastomer (component (A)), thereby enhancing heat resistance, oil resistance, and compression set resistance.

[0071] The phenolic resin crosslinking agent (component (E)) can be obtained by condensing a difunctional phenol dialcohol compound, or by condensing phenol or an alkyl-substituted phenol with an aldehyde compound, preferably formaldehyde, in an alkaline medium.

[0072] Examples of the phenolic resin crosslinking agent (E) include condensates of bifunctional phenol dialcohol compounds such as dimethylol alkylphenol resins, condensates of halogenated bifunctional phenol dialcohol compounds such as halogenated dimethylol alkylphenol resins, condensates of phenols and aldehyde compounds such as phenol formaldehyde resins, halides of such condensates, condensates of alkyl-substituted phenols and aldehyde compounds such as alkylphenol formaldehyde resins, and halogenated alkylphenol formaldehyde resins.

[0073] The dimethylol alkyl phenol resin is a condensate of a dimethylol phenol compound having a hydrocarbon group at the p-position, preferably a hydrocarbon group having 1 to 15 carbon atoms, more preferably a saturated hydrocarbon group having 1 to 15 carbon atoms, and even more preferably a saturated hydrocarbon group having 1 to 10 carbon atoms.

[0074] The halogenated dimethylol alkyl phenol resin is a resin having a structure in which at least one of the terminal alcoholic hydroxyl groups of the dimethylol alkyl phenol resin is halogenated with a halogen element such as bromine.

[0075] The alkylphenol formaldehyde resin is a condensate of formaldehyde and an alkyl-substituted phenol having a hydrocarbon group, preferably a hydrocarbon group having 1 to 15 carbon atoms, more preferably a saturated hydrocarbon group having 1 to 15 carbon atoms, and even more preferably a saturated hydrocarbon group having 1 to 10 carbon atoms, at the o-, m-, or p-position, preferably the p-position.

[0076] The halogenated alkylphenol formaldehyde resin is a resin having a structure in which at least one of the terminal alcoholic hydroxyl groups of the alkylphenol formaldehyde resin is halogenated with a halogen element such as bromine.

[0077] As the component (E), the phenolic resin crosslinking agent, one or more of these can be used.

[0078] The amount of the phenolic resin crosslinking agent (Component (E)) may be, from the viewpoints of heat resistance, oil resistance, and compression set resistance, preferably 0.5 parts by mass or more, more preferably 1.0 part by mass or more, even more preferably 2.0 parts by mass or more, and even more preferably 3.0 parts by mass or more, per 100 parts by mass of the ethylene-propylene-non-conjugated polyene copolymer elastomer (Component (A)). On the other hand, from the viewpoint of moldability, the amount of the phenolic resin crosslinking agent (Component (E)) may be, from the viewpoint of moldability, preferably 25 parts by mass or less, more preferably 20 parts by mass or less, even more preferably 15 parts by mass or less, even more preferably 12 parts by mass or less, and most preferably 9 parts by mass or less.

[0079] (F) Talc: In another preferred embodiment, the thermoplastic elastomer composition of the present invention may further contain the above-mentioned component (F) talc. The above-mentioned component (F) talc is a ground substance of a magnesium clay mineral known as hydrous magnesium silicate or talc (generally represented by the chemical formula 4SiO2·3MgO·2H2O), which is a scaly particle with a layered structure.

[0080] When a filler is added to a thermoplastic elastomer composition, moldability is usually reduced. However, surprisingly, the present inventors have discovered that the component (F) talc functions to improve the moldability of the thermoplastic elastomer composition of the present invention. Without intending to be bound by theory, the reason why the component (F) talc improves the moldability of the thermoplastic elastomer composition of the present invention is considered as follows. The component (F) talc is known to function as a crystallization nucleating agent for polypropylene-based resin compositions (see, for example, paragraph 0020 of JP 2023-054403 A). Due to its function as a crystallization nucleating agent, after the thermoplastic elastomer composition of the present invention is extruded through a die or injected into a mold, the component (B) polypropylene solidifies / crystallizes in the form of extremely fine islands, or in other words, while maintaining a well-dispersed state, before phase separation with the component (A) ethylene-propylene-non-conjugated polyene copolymer elastomer or the component (C) hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound proceeds. Furthermore, the talc component (F) has a scaly shape and has the property of easily aligning in one direction in the molten resin flow, resulting in a molded article with a good appearance.

[0081] The 50% diameter value (median diameter D50) in the volume-based cumulative fraction of particle diameter distribution of the component (F) talc, as measured by a laser diffraction / scattering method in accordance with JIS R1629:1997, may be preferably 1 to 40 μm, more preferably 2 to 30 μm, from the viewpoint of moldability.

[0082] As the component (F), talc, one or more of these can be used.

[0083] The amount of talc (component (F)) blended is not particularly limited as long as it does not detract from the object of the present invention, since it is an optional component. From the viewpoint of moldability, the amount of talc (component (F)) blended is preferably 5 to 150 parts by mass, more preferably 10 to 120 parts by mass, even more preferably 15 to 100 parts by mass, and even more preferably 20 to 80 parts by mass per 100 parts by mass of ethylene-propylene-non-conjugated polyene copolymer elastomer (component (A)).

[0084] (G) Crosslinking accelerator: In yet another preferred embodiment, the thermoplastic elastomer composition of the present invention may further contain (G) at least one or two or more crosslinking accelerators selected from the group consisting of zinc oxide, magnesium oxide, and stannous chloride, which allows the crosslinking function of the component (E) phenolic resin crosslinking agent to be more effectively exerted.

[0085] The amount of the crosslinking accelerator (G) is an optional component and is not particularly limited as long as it does not interfere with the objectives of the present invention. To ensure the desired effect of use, the amount of the crosslinking accelerator (G) is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 1 part by mass or more, and even more preferably 2 parts by mass or more, per 100 parts by mass of the ethylene-propylene-non-conjugated polyene copolymer elastomer (A). On the other hand, from the viewpoint of moldability, the amount of the crosslinking accelerator (G) is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, even more preferably 10 parts by mass or less, and even more preferably 6 parts by mass or less.

[0086] The thermoplastic elastomer composition of the present invention may further contain optional components other than the above components (A) to (G), as desired, to the extent that it does not contradict the object of the present invention.

[0087] Examples of the optional components include component (A) ethylene-propylene-non-conjugated polyene copolymer elastomer, component (B) polypropylene, and component (C) other thermoplastic resins other than hydrogenated block copolymers of aromatic vinyl compounds and conjugated diene compounds; component (D) other softeners or plasticizers other than non-aromatic rubber softeners; component (E) phenolic resin crosslinking agent, and component (G) other crosslinking agents or crosslinking accelerators other than crosslinking accelerators; component (F) other fillers other than talc, as well as additives, colorants, and flame retardants.

[0088] Examples of the other thermoplastic resins include ethylene-α-olefin-non-conjugated polyene copolymer elastomers other than component (A) above, polyethylenes such as high-pressure low-density polyethylene, linear low-density polyethylene, and high-density polyethylene, ethylene-α-olefin copolymers (containing no structural units derived from non-conjugated polyenes), ethylene-vinyl acetate copolymers, ethylene-unsaturated carboxylic acid copolymers, ethylene-unsaturated carboxylic acid alkyl ester copolymers, polypropylenes other than component (B) polypropylene, random copolymers of aromatic vinyl compounds and conjugated diene compounds, and hydrogenated products thereof, and block copolymers of aromatic vinyl compounds and conjugated diene compounds (non-hydrogenated).

[0089] Examples of the other softeners or plasticizers include esters of polycarboxylic acids such as di(2-ethylhexyl) phthalate with saturated aliphatic alcohols, plasticizers for polyvinyl chloride such as polyester-based plasticizers, and softeners for aromatic rubbers.

[0090] Examples of the other crosslinking agents or crosslinking accelerators include silicone resin crosslinking agents such as methylhydrogenpolysiloxane and alkylmethylpolysiloxane, maleimide resin crosslinking agents, and organic peroxides such as 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0091] Examples of the other fillers include inorganic fillers such as calcium carbonate, silica (silicon dioxide), mica, clay, hydrotalcite, and zeolite; and organic fillers such as crosslinked acrylic resin particles.

[0092] The inventors believe that, because pulverized mica functions as a crystallization nucleating agent for polypropylene resin compositions similar to the talc component (F) above and has a scaly shape, it will likely function to improve the moldability of the thermoplastic elastomer composition of the present invention. The inventors believe that pulverized mica can be used in the same manner as the talc component (F) above, particularly mica with a median diameter D50 in the same range (preferably 1 to 40 μm, more preferably 2 to 30 μm) and in the same blend amount (preferably 5 to 150 parts by mass, more preferably 10 to 120 parts by mass, even more preferably 15 to 100 parts by mass, and even more preferably 20 to 80 parts by mass).

[0093] Examples of the additives include weathering agents such as antioxidants, light stabilizers, and ultraviolet absorbers; antioxidants such as hindered phenol antioxidants, phosphite antioxidants, thioether antioxidants, and amine antioxidants; lubricants such as acid amides, fatty acids, fatty acid esters, fatty acid metal salts, waxes such as polyethylene wax, modified waxes such as modified polyethylene wax, silicone oils, and modified silicone oils; nucleating agents such as aromatic phosphate metal salts and gelols; antistatic agents such as glycerin fatty acid esters; and mold release agents, processing aids, and antifouling agents.

[0094] Examples of the colorant include inorganic colorants such as titanium dioxide (titania), red iron oxide, ultramarine (ultramarine blue), and carbon black; and organic colorants such as aniline black, quinacridone red, isoindolinone yellow, and phthalocyanine blue.

[0095] Examples of the flame retardant include antimony-based flame retardants, halogen-based flame retardants, metal hydroxides, zinc-based flame retardants, organic phosphate ester-based flame retardants, and nitrogen-containing compound-based flame retardants.

[0096] As the optional component, one or more of these may be used.

[0097] When the optional component is used, the amount of the component is not particularly limited as long as it does not contradict the object of the present invention. In one embodiment, the amount of the optional component may be 50 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, 5 parts by mass or less, 3 parts by mass or less, 1 part by mass or less, 0.5 parts by mass or less, 0 to 0.5 parts by mass, or about 0.01 to 50 parts by mass per 100 parts by mass of the ethylene-propylene-non-conjugated polyene copolymer elastomer (A).

[0098] In one embodiment, the thermoplastic elastomer composition of the present invention may not contain any one or more of the optional components described above.

[0099] As used herein, "not containing a certain component" means that the component is not intentionally blended. In the technical field of thermoplastic elastomer compositions, when a component is intentionally blended, it is typically blended in an amount of 0.01 part by mass or more. Therefore, "not containing a certain component" can also be rephrased as meaning that the content of the component is typically less than 0.01 part by mass, preferably 0.001 part by mass or less, and more preferably 0 to 0.0001 part by mass, per 100 parts by mass of the ethylene-propylene-non-conjugated polyene copolymer elastomer (A) described above.

[0100] 2. Manufacturing method: The thermoplastic elastomer composition of the present invention can be obtained by using any melt kneader to charge the above components (A) to (C), (E), and any optional components used as desired, simultaneously or in any order, and melt kneading, preferably at a resin temperature of 160 to 240° C. The kneading time may be preferably 3 to 20 minutes, more preferably 5 to 10 minutes.

[0101] Examples of the melt kneader include batch kneaders such as pressure kneaders and mixers, extrusion kneaders such as single-screw extruders, co-rotating twin-screw extruders, and counter-rotating twin-screw extruders, and calendar roll kneaders. These may be used in any combination.

[0102] The resulting thermoplastic elastomer composition can be pelletized by any method and then molded into any article by any method, such as hot cutting, strand cutting, or underwater cutting.

[0103] Alternatively, the obtained thermoplastic elastomer composition may be subjected to molding as it is (without going through a pelletizing step).

[0104] 3. Goods: The article of the present invention comprises the thermoplastic elastomer composition of the present invention. In one embodiment, the article of the present invention may be one in which the thermoplastic elastomer composition of the present invention is laminated on the surface of a metal or resin core material or structural member.

[0105] The article of the present invention may be a part of an automobile, building, furniture, home appliance, or the like. In one embodiment, the article of the present invention may be an automobile part or a building part. Examples of the automobile part as the article of the present invention include a window molding, a window seal, a glass run channel, a gasket, a belt molding, a weatherstrip, a door trim, a shift knob, a parking brake, an assist grip, and a seat belt cover. Examples of the building part as the article of the present invention include a window molding, a window seal, a gasket, a window frame, a handrail, and a doorknob. [Example]

[0106] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0107] Measurement method The following tests (a) to (g) were carried out after conditioning the test specimens in an environment of 23±2°C temperature and 50±10% humidity for 16 hours or more, and then under the same temperature and humidity conditions unless otherwise specified.

[0108] (a) Injection moldability: Using the thermoplastic elastomer composition, a sheet measuring 130 mm in length, 130 mm in width, and 2 mm in thickness was injection-molded using an injection molding machine with a clamping pressure of 120 tons under the following conditions: molding temperature 240°C, mold temperature 30°C, injection speed 55 mm / sec, injection pressure 140 MPa, dwell pressure 40 MPa, injection time 5 seconds, and cooling time 20 seconds. The obtained sheet was visually observed and evaluated by touch according to the following criteria. A (very good): No flow marks or sink marks were observed on the sheet, and the surface of the sheet was very smooth and felt very smooth. B (good): No flow marks or sink marks were observed on the sheet, and the surface of the sheet was smooth and felt smooth to the touch. C (pass): No flow marks or sink marks were observed on the sheet, and the surface of the sheet was smooth, but the feel was slightly powdery. D (fail): At least one of flow marks and sink marks was observed on the sheet, or powdery bumps were observed on the surface.

[0109] (b) Extrusion moldability: The thermoplastic elastomer composition was extrusion-molded into a sheet having a width of 50 mm and a thickness of 0.5 mm using a 40 mm extruder at a die outlet resin temperature of 200° C. The obtained sheet was visually observed and evaluated by touch according to the following criteria. A (very good): The shape of the sheet was very stable, the edges of the sheet were very neat, the surface of the sheet was very smooth, and it felt very smooth. B (good): The shape of the sheet was stable, the edges of the sheet were clearly defined, the surface of the sheet was smooth, and it felt smooth to the touch. C (pass): The shape of the sheet was stable, the edges of the sheet were clearly defined, and the surface of the sheet was smooth, but the feel was slightly powdery. D (fail): The sheet shape was unstable, the edges of the sheet were not clean, and powdery bumps were observed on the surface of the sheet.

[0110] FIG. 2(1) shows the extrusion molded sheet of Example 1 (rated A rank), and FIG. 2(2) shows the extrusion molded sheet of Example 2 (rated D rank).

[0111] (c) Durometer hardness (Type A): In accordance with JIS K6253-2012, a 6.3 mm thick press sheet made from the thermoplastic elastomer composition was used as a test piece, and the 15-second value of the durometer hardness (Type A) was measured. In the table, the durometer hardness (Type A) is referred to as "A hardness."

[0112] (d) Tensile properties: In accordance with JIS K6251:2017, a dumbbell-shaped No. 3 test piece was punched out from the sheet obtained in the above test (a) Injection Molding, and a tensile test was performed at a test speed of 500 mm / min. From the obtained stress-strain curve, the tensile stress at break (unit: MPa), 100% strain tensile stress (unit: MPa), and tensile strain at break (unit: %) were calculated. In the table, the 100% strain tensile stress is referred to as the "100% modulus."

[0113] (E) Compression set 1: In accordance with JIS K6262-2003, test pieces were punched out from a 6.3 mm thick press sheet made using the thermoplastic elastomer composition, and the compression set (unit: %) was measured under conditions of 25% compression deformation, a temperature of 70°C, and 22 hours.

[0114] (F) Compression set 2: In accordance with JIS K6262-2003, test pieces were punched out from a 6.3 mm thick press sheet made using the thermoplastic elastomer composition, and the compression set (unit: %) was measured under conditions of 25% compression deformation, a temperature of 120°C, and 22 hours.

[0115] (g) Oil resistance: In accordance with JIS K6258-2016, test pieces were punched out from the sheets obtained in the above test (a) Injection moldability, and No. 3 oil (IRM903) listed in Table A.3 of Appendix A of the JIS standard was used as the test lubricant. After immersion at a temperature of 120°C for 22 hours, the volume change rate (unit: %) was calculated using equation (2) of JIS standard 8.1.3 volume change.

[0116] Raw materials used (A) Ethylene-propylene-non-conjugated polyene copolymer elastomer: (A-1) Ethylene-propylene-ethylidene norbornene copolymer "Nodel 4760P (trade name)" from The Dow Chemical Company, Mooney viscosity (ML 1+4125°C) 60, content of structural units derived from ethylene 67% by mass, content of structural units derived from ethylidene norbornene 4.9% by mass.

[0117] (B1) Polypropylene: (B1-1) Propylene and ethylene block copolymer "VB370A (trade name)" manufactured by Sunallomer Co., Ltd., melt mass flow rate (temperature 230°C, load 21.18 N) 1.3 g / 10 min, melting point 164°C, melting enthalpy 89 J / g. (B1-2) Propylene homopolymer "PX201N (trade name)" manufactured by Sunallomer Co., Ltd., melt mass flow rate (temperature 230°C, load 21.18 N) 0.8 g / 10 min, melting point 163°C, fusion enthalpy 87 J / g. (B1-3) Globalene 7012 (trade name), a propylene and ethylene block copolymer from LCY (Lee Chang Yung Chemical Industry Co., Ltd.), melt mass flow rate (temperature 230°C, load 21.18N) 0.95g / 10min.

[0118] (B2) Polypropylene: (B2-1) "BC3HF (trade name)", a propylene and ethylene block copolymer manufactured by Japan Polypropylene Corporation, with a melt mass flow rate (temperature 230°C, load 21.18 N) of 8.5 g / 10 min, a melting point of 164°C, and a melting enthalpy of 88 J / g. (B2-2) Propylene homopolymer "PM900A (trade name)" from Sunallomer Co., Ltd., melt mass flow rate (temperature 230°C, load 21.18 N) 30 g / 10 min, melting point 163°C, melting enthalpy 106 J / g. (B2-3) Japan Polypropylene Corporation's propylene and ethylene block copolymer "BC08AHA (trade name)", melt mass flow rate (temperature 230°C, load 21.18N) 80g / 10min

[0119] (C) Hydrogenated block copolymer of aromatic vinyl compound and conjugated diene compound: (C-1) Kuraray Co., Ltd. hydrogenated block copolymer of styrene and isoprene (styrene-ethylene-ethylene-propylene-styrene copolymer) "Septon 4044 (trade name)", styrene-derived structural unit content 32% by mass, mass average molecular weight 1.7 × 10 5 , number average molecular weight 1.4×10 5 . (C-2) Kuraray Co., Ltd. hydrogenated block copolymer of styrene and isoprene (styrene-ethylene-ethylene-propylene-styrene copolymer) "Septon 4077 (trade name)", styrene-derived structural unit content 30% by mass, mass average molecular weight 5.4 × 10 5 , number average molecular weight 4.3×10 5 . (C-3) Asahi Kasei Corporation's hydrogenated block copolymer of styrene and 1,3-butadiene (styrene-ethylene-butene-styrene copolymer) "Tuftec N504 (trade name)", with a styrene-derived structural unit content of 32% by mass. (C-4) Kuraray Co., Ltd.'s hydrogenated block copolymer of styrene and β-farnesene, "Septon BIO SF903 (trade name)," with a styrene-derived structural unit content of 30% by mass.

[0120] (D) Non-aromatic rubber softeners: (D-1) Paraffin oil "Diana Process Oil PW-90 (product name)" from Idemitsu Kosan Co., Ltd.

[0121] (E) Phenolic resin crosslinker: (E-1) "Tackirol 202 (trade name)," a phenolic resin crosslinking agent containing alkylphenol formaldehyde resin (CAS number 26678-93-3) manufactured by Taoka Chemical Co., Ltd. as the active ingredient, with an active ingredient content of over 90% by mass. The amounts listed in the table are for "Tackirol 202 (trade name)."

[0122] (F) Talc: (F-1) Matsumura Sangyo Co., Ltd.'s talc "High Filler #17GS (product name)", median diameter D50 is 6.5 μm.

[0123] (G) Crosslinking accelerator: (G-1) Anhydrous stannous chloride. CAS number 7772-99-8. (G-2) Two types of zinc oxide specified in JIS K1410-1995.

[0124] (H) Other ingredients: (H-1) Sakai Chemical Industry Co., Ltd.'s polyethylene wax "LBT-77 (product name)". (H-2) BASF Ltd.'s hindered phenol antioxidant "Irganox 1010 (trade name)".

[0125] Example 1 A blend consisting of 100 parts by weight of component (A-1), 15 parts by weight of component (B1-1), 6 parts by weight of component (B2-1), 53 parts by weight of component (C-1), 320 parts by weight of component (D-1), 6.0 parts by weight of component (E-1) (more than 5.4 parts by weight as active ingredient), 55 parts by weight of component (F-1), 2.0 parts by weight of component (G-1), 2.0 parts by weight of component (G-2), 1.0 part by weight of component (H-1), and 0.2 parts by weight of component (H-2) was melt-kneaded in a 20 L pressure kneader at a resin temperature of 180°C upon discharge for 5 to 10 minutes to obtain a thermoplastic elastomer composition. Tests (a) to (g) were performed. The results are shown in Table 1.

[0126] Examples 2-14 A thermoplastic elastomer composition was obtained in the same manner as in Example 1, except that the formulation was changed as shown in any one of Tables 1 to 3. The above tests (a) to (g) were carried out. The results are shown in any one of Tables 1 to 3.

[0127] [Table 1]

[0128] [Table 2]

[0129] [Table 3]

[0130] The thermoplastic elastomer composition of the present invention was found to have excellent injection moldability and extrusion moldability. The preferred thermoplastic elastomer composition of the present invention was also found to have good flexibility and compression set resistance. Furthermore, since the oil resistance value of the above test (g) for a vulcanized EPDM rubber having a durometer hardness (Type A, 15-second value) of 60 was 180%, the preferred thermoplastic elastomer composition of the present invention was also determined to have good oil resistance. Therefore, it was considered that the thermoplastic elastomer composition of the present invention can be suitably used as a material to be laminated onto the surface of a metal or resin core material or structural member. Furthermore, it was considered that an article in which the thermoplastic elastomer composition of the present invention is laminated onto the surface of a metal or resin core material or structural member can be suitably used as a component for automobiles, buildings, furniture, home appliances, and the like. [Brief explanation of the drawings]

[0131] [Figure 1] 1 is an example of measurement of the melting point and melting enthalpy of polypropylene. [Figure 2] Photographs of extruded sheets of Examples 1 and 2.

Claims

1. (A) 100 parts by mass of ethylene-propylene-non-conjugated polyene copolymer elastomer, (B) 5 to 250 parts by mass of polypropylene, (C) 5 to 120 parts by mass of a hydrogenated block copolymer of an aromatic vinyl compound and a conjugated diene compound, (D) 0 to 500 parts by mass of a non-aromatic rubber softener, and (E) 0.5 to 25 parts by mass of a phenolic resin crosslinking agent, wherein the component (B) polypropylene comprises (B1) Polypropylene having a melt mass flow rate of 0.1 to 3.0 g / 10 min measured at a temperature of 230 ° C and a load of 21.18 N in accordance with JIS K7210-1:2014. (B2) Made of polypropylene having a melt mass flow rate of more than 3.0 g / 10 min and less than 100 g / 10 min, measured in accordance with JIS K7210-1:2014 at a temperature of 230 ° C. and a load of 21.18 N; Thermoplastic elastomer composition.

2. The thermoplastic elastomer composition according to claim 1, further comprising 1 to 100 parts by mass of (F) talc per 100 parts by mass of the component (A) ethylene-propylene-non-conjugated polyene copolymer elastomer.

3. 2. The thermoplastic elastomer composition according to claim 1, wherein the mass ratio of the blended amount of the polypropylene component (B1) to the blended amount of the polypropylene component (B2) (blended amount of the component (B1) / blended amount of the component (B2)) is 98 / 2 to 5 / 95.

4. 2. The thermoplastic elastomer composition according to claim 1, wherein the component (B1) polypropylene comprises a copolymer of propylene with one or more other α-olefins.

5. 2. The thermoplastic elastomer composition according to claim 1, wherein the component (B2) polypropylene comprises a copolymer of propylene with one or more other α-olefins.

6. 2. The thermoplastic elastomer composition according to claim 1, wherein the amount of the non-aromatic rubber softener (D) is 140 to 400 parts by mass.

7. 2. The thermoplastic elastomer composition according to claim 1, wherein the component (C), a hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound, comprises a hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound, the hydrogenated product having a structural unit derived from β-farnesene.

8. An article comprising the thermoplastic elastomer composition according to any one of claims 1 to 7.

9. An article comprising a metal or resin core material and the thermoplastic elastomer composition according to any one of claims 1 to 7 laminated on the surface thereof.

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