Thermoplastic elastomer compositions, injection molded articles, and automotive interior parts

Abstract

To provide a thermoplastic elastomer composition and the like, the composition having excellent fluidity and flexibility of a molded product and capable of reducing the stickiness of a molded product.SOLUTION: There is provided a thermoplastic elastomer composition which comprises a propylene-based polymer (A), an olefin-based copolymer (B) and a softening agent (C), wherein the (B) contains an ethylene / an α-olefin copolymer (B1) containing ethylene and an α-olefin unit having 3 to 20 carbon atoms and an ethylene / propylene / non-conjugated polyene copolymer (B2), the content of the (B1) in the (B) is 0 to 99 mass%, the content of the (B2) is 1 to 100 mass% [provided that the total of the content of (B1) and (B2) is defined as 100 mass%], the content of the (A) is 25 to 300 pts.mass based on 100 pts.mass of the (B) and the content of the (C) is more than 120 pts.mass and 300 pts.mass or less based on 100 pts.mass of the (C).SELECTED DRAWING: None

Description

[Technical Field]

[0001] This disclosure relates to a thermoplastic elastomer composition, an injection-molded article containing the thermoplastic elastomer composition, and an automotive interior part made from the injection-molded article. [Background technology]

[0002] Thermoplastic elastomer compositions produced by so-called dynamic crosslinking, in which a resin that does not exhibit radical crosslinking properties, such as polypropylene (PP), and a radically crosslinkable elastomer are crosslinked while melt-kneading in an extruder in the presence of a radical initiator, are widely used in automotive parts such as interior surface materials.

[0003] Such rubber-based compositions include olefin-based elastomer compositions using ethylene-propylene-diene rubber (EPDM) (see Patent Documents 1 and 2). Compositions in which hydrogenated rubber is dynamically crosslinked are also known (see Patent Documents 3 and 4). Furthermore, thermoplastic elastomer compositions using hydrogenated copolymers of olefin resins, vinyl aromatic compounds, and conjugated diene compounds have been disclosed (see Patent Documents 5 and 6). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 8-120127 [Patent Document 2] Japanese Patent Application Publication No. 9-137001 [Patent Document 3] Patent No. 2737251 [Patent Document 4] Japanese Patent Publication No. 2004-67798 [Patent Document 5] Japanese Patent Publication No. 2001-49051 [Patent Document 6] Japanese Patent Publication No. 2005-89656 [Overview of the project] [Problems that the invention aims to solve]

[0005] Thermoplastic elastomer compositions used in automotive interior surface materials generally require high fluidity and high flexibility in the molded product. While it is common practice to add large amounts of softeners to increase the fluidity of the composition without compromising the flexibility of the molded product, adding large amounts of softeners tends to cause stickiness on the surface of the molded product, impairing its tactile feel. In recent years, from the perspective of automotive design, there has been a demand to suppress the stickiness of the surface of automotive interior upholstery materials while increasing the flexibility of molded products and the fluidity of the composition. Therefore, there is a desire for the realization of thermoplastic elastomer compositions that fully satisfy all of these performance requirements.

[0006] In view of the above situation, this disclosure provides a thermoplastic elastomer composition that is excellent in fluidity and flexibility of molded articles and can suppress stickiness of molded articles, an injection molded article containing the composition, and an automotive interior part made from the injection molded article. [Means for solving the problem]

[0007] [1] A propylene polymer (A) and Olefin copolymer (B) and Softener (C), It contains, The olefin copolymer (B) is Ethylene-α-olefin copolymer (B1) containing ethylene and α-olefin units having 3 to 20 carbon atoms, Ethylene-propylene-non-conjugated polyene copolymer (B2) and It contains, The olefin copolymer (B) contains 0 to 99% by mass of the ethylene-α-olefin copolymer (B1), and the ethylene-propylene-unconjugated polyene copolymer (B2) contains 1 to 100% by mass [provided that the sum of the contents of (B1) and (B2) is 100% by mass]. The content of the propylene-based polymer (A) is 25 to 300 parts by mass with respect to 100 parts by mass of the olefin-based copolymer (B), and a thermoplastic elastomer composition in which the content of the softening agent (C) is more than 120 parts by mass and 300 parts by mass or less with respect to 100 parts by mass of the olefin-based copolymer (B).

[0008] [2] The content of the ethylene·α-olefin copolymer (B1) in the olefin-based copolymer (B) is 0 to 95% by mass, and the content of the ethylene·propylene·non-conjugated polyene copolymer (B2) is 5 to 100% by mass [however, the total content of (B1) and (B2) is 100% by mass]. a thermoplastic elastomer composition according to [1], in which the content of the softening agent (C) is more than 120 parts by mass and 290 parts by mass or less with respect to 100 parts by mass of the olefin-based copolymer (B).

[0009] [3] The thermoplastic elastomer composition further contains a hydrogenated product (D) of a block copolymer, the thermoplastic elastomer composition according to [1] or [2].

[0010] [4] The content of the hydrogenated product (D) of the block copolymer is 30 to 350 parts by mass with respect to 100 parts by mass of the olefin-based copolymer (B), the thermoplastic elastomer composition according to [3].

[0011] [5] ​​​​​​​​​​​ An injection-molded article comprising a thermoplastic elastomer composition as described in any one of [1] to [6].

[0014] [8] Automotive interior parts made from injection molded products as described in [7].

[0015] [9] A propylene polymer (A) and Olefin copolymer (B) and Softener (C), It contains, The olefin copolymer (B) is Ethylene-α-olefin copolymer (B1) containing ethylene and α-olefin units having 3 to 20 carbon atoms, Ethylene-propylene-non-conjugated polyene copolymer (B2) and It contains, The olefin copolymer (B) contains 0 to 99% by mass of the ethylene-α-olefin copolymer (B1), and the ethylene-propylene-unconjugated polyene copolymer (B2) contains 1 to 100% by mass [provided that the sum of the contents of (B1) and (B2) is 100% by mass]. The content of the propylene polymer (A) is 25 to 300 parts by mass per 100 parts by mass of the olefin copolymer (B), and A method for producing a thermoplastic elastomer composition, wherein the content of the softening agent (C) is more than 120 parts by mass and 300 parts by mass or less per 100 parts by mass of the olefin copolymer (B), A method for producing a thermoplastic elastomer composition, comprising the step of dynamically heat-treating the propylene polymer (A), the olefin copolymer (B), and the softener (C) in the presence of a crosslinking agent (F). [Effects of the Invention]

[0016] According to this disclosure, it is possible to provide a thermoplastic elastomer composition that is excellent in fluidity and flexibility of molded articles and can suppress stickiness of molded articles, an injection molded article containing the composition, and an automotive interior part made from the injection molded article. [Modes for carrying out the invention]

[0017] In this disclosure, unless otherwise specified, the expressions "XX or greater and YY or less" and "XX to YY" that represent a numerical range mean a numerical range that includes the lower and upper limits. Furthermore, when numerical ranges are listed in steps, the upper and lower limits of each numerical range can be combined in any way. Furthermore, the phrase "A and / or B" is a concept that includes the cases of A, B, and both A and B.

[0018] <Propylene-based polymer (A)> A propylene-based polymer (A) [hereinafter sometimes referred to as "component (A)"], which is one of the components of the thermoplastic elastomer composition of this disclosure, is a polymer in which the content of propylene-derived structural units among the structural units constituting the polymer is 50 mol% or more, and preferably the content of propylene-derived structural units in component (A) is 90 mol% or more.

[0019] The component (A) according to the present invention may be one type or two or more types. Component (A) of the present invention may be a propylene homopolymer, or a copolymer of propylene and a comonomer other than propylene.

[0020] The structure of component (A) according to the present invention is not particularly limited. For example, the propylene-derived constituent unit portion may be an isotactic, syndiotactic, or atactic structure. Furthermore, the copolymer may be random (also called random PP), block (also called block PP: bPP), or graft type.

[0021] The comonomer can be any other monomer copolymerizable with propylene, and α-olefins having 2 or 4 to 10 carbon atoms are preferred. Specifically, examples include ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, and 1-decene, among which ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, and 1-octene are preferred. One comonomer may be used, or two or more may be used. The content of comonomer-derived structural units in the copolymer is preferably 10 mol% or less, from the viewpoint of heat resistance and mechanical strength.

[0022] Component (A) relating to this disclosure may be synthesized by conventionally known methods or a commercially available product may be used. Examples of commercially available products include polypropylene from Sun Allomer Co., Ltd., Prime Polypropylene from Prime Polymer Co., Ltd., Novatec from Nippon Polypropylene Co., Ltd., and SCG PP from SCG Plastics Co., Ltd.

[0023] Component (A) relating to this disclosure may be a crystalline polymer or an amorphous polymer. Here, crystalline means that a melting point (Tm) is observed in differential scanning calorimetry (DSC). If component (A) of the present disclosure is a crystalline polymer, its melting point (according to the measurement method of JIS K 7121) is preferably 100°C or higher, more preferably 120°C or higher, preferably 180°C or lower, and more preferably 170°C or lower, from the viewpoint of heat resistance and the like.

[0024] The MFR (measured according to the ASTM D 1238-65T method, at 230°C and a 2.16 kg load) of component (A) relating to this disclosure is preferably 0.1 to 100 g / 10 min, more preferably 0.1 to 50 g / 10 min, and even more preferably 0.1 to 5.0 g / 10 min. When the MFR of component (A) relating to this disclosure is within the above range, a composition with excellent heat resistance, mechanical strength, fluidity, and moldability can be easily obtained.

[0025] <Olefin copolymer (B)> One of the components of the thermoplastic elastomer composition of this disclosure, the olefin copolymer (B) [hereinafter sometimes referred to as "component B"], contains ethylene-α-olefin copolymer (B1) containing ethylene and α-olefin units having 3 to 20 carbon atoms, and ethylene-propylene-unconjugated polyene copolymer (B2), wherein the content of ethylene-α-olefin copolymer (B1) in the olefin copolymer (B) is 0 to 99% by mass, preferably 0 to 95% by mass, more preferably 0 to 85% by mass, and even more preferably 0 to 75% by mass, and the content of ethylene-propylene-unconjugated polyene copolymer (B2) is 1 to 100% by mass, preferably 5 to 100% by mass, more preferably 15 to 100% by mass, and even more preferably 25 to 100% by mass [provided that the total content of (B1) and (B2) is 100% by mass].

[0026] Component (B) may be ethylene-propylene-non-conjugated polyene copolymer (B2) alone, but if component (B) also contains ethylene-α-olefin copolymer (B1), the resulting thermoplastic elastomer composition exhibits superior stickiness and fluidity.

[0027] <Ethylene-α-olefin copolymer (B1)> One of the components contained in the olefin copolymer (B) relating to this disclosure is the ethylene-α-olefin copolymer (B1) [hereinafter sometimes referred to as "component (B1)"], which is an ethylene-α-olefin copolymer containing units derived from ethylene and units derived from α-olefins having 3 to 20 carbon atoms.

[0028] The component (B1) relating to this disclosure can be obtained by copolymerizing ethylene with at least α-olefins having 3 to 20 carbon atoms. Examples of α-olefins having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, and 1-dodecene. Among these, α-olefins having 3 to 12 carbon atoms are preferred from the viewpoint of imparting flexibility, propylene, 1-butene, and 1-octene are more preferred, and 1-octene is even more preferred.

[0029] The component (B1) relating to this disclosure typically contains 70 to 99 mol%, preferably 80 to 97 mol%, of units derived from ethylene, and 1 to 30 mol%, preferably 3 to 20 mol%, of units derived from α-olefins having 3 to 20 carbon atoms [provided that the total amount of units derived from ethylene and units derived from α-olefins having 3 to 20 carbon atoms is 100 mol%]. The content ratio of units derived from ethylene being within the above range is preferable for obtaining a thermoplastic elastomer composition with excellent mechanical strength.

[0030] The component (B1) relating to this disclosure typically has an MFR (ASTM D1238 load 2.16 kg, temperature 190°C) of 0.1 to 20 g / 10 min, preferably in the range of 0.3 to 10 g / 10 min. By using component (B1) within the above range as the MFR, a thermoplastic elastomer composition with superior balance characteristics between fluidity and mechanical strength can be obtained. The component (B1) relating to this disclosure typically has a density of 0.8 to 0.9 g / cm³. 3 It is within the range.

[0031] The component (B1) relating to this disclosure can be produced using known polymerization catalysts such as Ziegler-Natta catalysts, vanadium-based catalysts, and metallocene catalysts. The polymerization method is not particularly limited and can be carried out using liquid-phase polymerization methods such as solution polymerization, suspension polymerization, and bulk polymerization, gas-phase polymerization, and other known polymerization methods. Furthermore, these copolymers are not limited as long as they achieve the effects of the present invention and are available as commercial products. Examples of commercial products include Engage 8842 (ethylene-1-octene copolymer) from Dow Chemical, Vistalon® from ExxonMobil, and Esprene®, Tuffmer P®, and Tuffmer A® from Sumitomo Chemical Co., Ltd.

[0032] <Ethylene-propylene-non-conjugated polyene copolymer (B2)> One of the components contained in the olefin copolymer (B) relating to this disclosure, ethylene-propylene-non-conjugated polyene copolymer (B2) [hereinafter sometimes referred to as "component (B2)"], is obtained by copolymerizing ethylene with an α-olefin having 3 to 20 carbon atoms and a non-conjugated polyene. The component (B2) relating to this disclosure is a copolymer having structural units derived from ethylene, structural units derived from α-olefins having 3 to 20 carbon atoms, and structural units derived from non-conjugated polyenes. The component (B2) relating to this disclosure may be used alone or in combination of two or more components.

[0033] Specific examples of α-olefins having 3 to 20 carbon atoms that constitute component (B2) related to this disclosure include propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-nonadecene, 1-eicosene, 9-methyl-1-decene, 11-methyl-1-dodecene, and 12-ethyl-1-tetradecene. As the α-olefin having 3 to 20 carbon atoms, α-olefins having 3 to 12 carbon atoms are preferred, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene and 1-octene are more preferred, and propylene is even more preferred. α-olefins with 3 to 20 carbon atoms can be used individually or in combination of two or more.

[0034] The non-conjugated polyenes constituting component (B2) relating to this disclosure include, specifically, chain-like non-conjugated dienes such as 1,4-hexadiene, 3-methyl-1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 4,5-dimethyl-1,4-hexadiene, and 7-methyl-1,6-octadiene; methyltetrahydroindene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 5-vinylidene-2-norbornene, and 6-chloromethyl-5-isopropane Examples include cyclic non-conjugated dienes such as nyl-2-norbornene, 5-vinyl-2-norbornene, 5-isopropenyl-2-norbornene, 5-isobutenyl-2-norbornene, cyclopentadiene, and norbornadiene; and trienes such as 8-methyl-4-ethlylidene-1,7-nonadienene, 4-ethlylidene-1,7-undecadienene, 2,3-diisopropylidene-5-norbornene, 2-ethlylidene-3-isopropylidene-5-norbornene, 2-propenyl-2,2-norbornadiene, and 4-ethlylidene-8-methyl-1,7-nonadienene. Among these, 5-ethlylidene-2-norbornene and 5-vinyl-2-norbornene are preferred. These non-conjugated polyenes can be used individually or in combination of two or more.

[0035] Examples of the component (B2) relating to this disclosure include ethylene-propylene-5-ethylidene-2-norbornene random copolymer and ethylene-propylene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene random copolymer. The component (B2) relating to this disclosure has a molar ratio of ethylene to α-olefins having 3 to 20 carbon atoms (ethylene / α-olefin), in other words, a molar ratio of ethylene-derived constituent units to α-olefin-derived constituent units having 3 to 20 carbon atoms, which is usually 50 / 50 to 90 / 10, and preferably 50 / 50 to 85 / 15.

[0036] The component (B2) relating to this disclosure contains constituent units derived from non-conjugated polyenes in an amount typically ranging from 1.0 to 25.0% by mass, preferably 3.0 to 20% by mass, and more preferably 4.0 to 15% by mass.

[0037] The iodine value of component (B2) relating to this disclosure is preferably 1 to 50 g / 100 g, more preferably 3.0 to 40.0 g / 100 g, and even more preferably 5.0 to 35.0 g / 100 g. When the iodine value is within the above range, a crosslinked body with a high crosslink density can be obtained, which is preferable because it can improve the oil retention of the thermoplastic elastomer composition.

[0038] The component (B2) relating to this disclosure typically has an intrinsic viscosity [η] measured at 135°C in decalin, preferably 0.5 to 7.0 dl / g, more preferably 1.0 to 5.0 dl / g, and even more preferably 1.0 to 4.0 dl / g. An intrinsic viscosity within this range is preferable because it provides a good balance between physical properties and processability.

[0039] The component (B2) relating to this disclosure may be a commercially available product or a polymer obtained by polymerization.

[0040] Method for producing ethylene-propylene-non-conjugated polyene copolymer (B2) The component (B2) relating to this disclosure can be prepared by conventionally known methods as described in Japanese Patent Publication No. 9-71617, Japanese Patent Publication No. 9-71618, Japanese Patent Publication No. 9-208615, Japanese Patent Publication No. 10-67823, Japanese Patent Publication No. 10-67824, Japanese Patent Publication No. 10-110054, etc., and is not particularly limited, but is preferably manufactured by the following method, for example.

[0041] Component (B2) relating to this disclosure is obtained by random copolymerizing ethylene, an α-olefin having 3 to 20 carbon atoms, and a non-conjugated polyene in the presence of a catalyst mainly composed of a vanadium compound represented by the following general formula (Ia) or the following general formula (Ib) and an organoaluminum compound represented by the following general formula (II), under the conditions of a polymerization temperature of 30 to 60°C, particularly preferably 30 to 59°C, a polymerization pressure of 0.4 to 5.0 MPa, particularly preferably 0.5 to 4.0 MPa, and a molar ratio of the supply amount of non-conjugated polyene to ethylene (non-conjugated polyene / ethylene) of 0.01 to 0.2. Copolymerization is preferably carried out in a hydrocarbon medium.

[0042] [Vanadium compounds] Vanadium compounds are soluble components in the hydrocarbon medium of polymerization reaction systems, and specifically, VO(OR) a X b ...(Ia) or V(OR) c X d ...(Ib) (In the formula, R is a hydrocarbon group, X is a halogen atom, and 0≦a≦3, 0≦b≦3, 2≦a+b≦3, 0≦c≦4, 0≦d≦4, 3≦c+d≦4) Vanadium compounds represented by these, or their electron-donor adducts, can be cited as representative examples.

[0043] More specifically, VOCl3, VO(OC2H5)Cl2, VO(OC2H5)2Cl, VO(O-iso-C3H7)Cl2, VO(On-C4H9)Cl2, VO(OC2H5)3, VOBr3, VCl4, VOCl3, VO(On-C4H9)3, VCl3·2OC6H 12 Examples include OH.

[0044] [Organoaluminum compounds] Organoaluminum compounds are compounds represented by the following general formula (II). R' m AlX'3-m ···(II) (In the formula, R’ is a hydrocarbon group, X’ is a halogen atom, and m is 1 to 3.)

[0045] Specific examples of the organoaluminum compound include trialkylaluminums such as triethylaluminum, tributylaluminum, and triisopropylaluminum; dialkylaluminum alkoxides such as diethylaluminum ethoxide and dibutylaluminum butoxide; alkylaluminum sesquialkoxides such as ethylaluminum sesquiethoxide and butylaluminum sesquibutoxide; partially alkoxylated alkylaluminums having an average composition represented by R 1 0.5 Al(OR 1 ) 0.5 and the like; dialkylaluminum halides such as diethylaluminum chloride, dibutylaluminum chloride, and diethylaluminum bromide; partially halogenated alkylaluminums such as alkylaluminum sesquichlorides such as ethylaluminum sesquichloride, butylaluminum sesquichloride, and ethylaluminum sesquibromide, and alkylaluminum dihalides such as ethylaluminum dichloride, propylaluminum dichloride, and butylaluminum dibromide; partially hydrogenated alkylaluminums such as dialkylaluminum hydrides such as diethylaluminum hydride and dibutylaluminum hydride, and alkylaluminum dihydrides such as ethylaluminum dihydride and propylaluminum dihydride; and partially alkoxylated and halogenated alkylaluminums such as ethylaluminum ethoxychloride, butylaluminum butoxychloride, and ethylaluminum ethoxybromide, etc. can be mentioned.

[0046] In this disclosure, it is preferable to use a blend of a soluble vanadium compound represented as VOCl3 from compound (Ia) and Al(OC2H5)2Cl / Al2(OC2H5)3Cl3 from compound (II) (with a blend ratio (molar ratio) of 1 / 5 or more) as a catalyst component, as this yields the copolymer rubber (A) having an insoluble content of 1% or less after Soxhlet extraction (solvent: boiling xylene, extraction time: 3 hours, mesh: 325).

[0047] Furthermore, as the catalyst used in the copolymerization described above, a so-called metallocene catalyst, such as a metallocene catalyst described in Japanese Patent Publication No. 9-40586 or Japanese Patent Publication No. 2010-241897, may be used. In addition, as the catalyst used in the copolymerization described above, a non-metallocene catalyst, such as a transition metal complex catalyst described in Japanese Patent Publication No. WO2006 / 121086, may also be used.

[0048] <Softener (C)> The softener (C) [hereinafter sometimes referred to as "component (C)"], which is one of the components of the thermoplastic elastomer composition of this disclosure, is not particularly limited, but plasticizers commonly used in rubber can be used. From the viewpoint of compatibility with the above-mentioned propylene polymer (A) and ethylene-α-olefin copolymer (B), a process oil consisting of hydrocarbons such as paraffinic, naphthenic, and aromatic hydrocarbons is preferred. Among these components (C), a process oil mainly composed of paraffinic hydrocarbons is preferred from the viewpoint of weather resistance and colorability, and a process oil mainly composed of naphthenic hydrocarbons is preferred from the viewpoint of compatibility. From the viewpoint of thermal and light stability, the content of aromatic hydrocarbons in the process oil is preferably 10% or less, more preferably 5% or less, and even more preferably 1% or less, in terms of the carbon number ratio specified in ASTM D2140-97.

[0049] <Hydrogenated block copolymer (D)> One of the components of the thermoplastic elastomer composition of this disclosure is a hydrogenated block copolymer (D) [hereinafter sometimes referred to as "component (D)" or "hydrogenated product (D)"], which is a hydrogenated block copolymer having at least one block mainly composed of conjugated diene monomer units and at least one block mainly composed of vinyl aromatic monomer units. Component (D) relating to this disclosure is obtained by hydrogenating (hereinafter sometimes referred to as "hydrogenation") at least a portion of monomer units derived from a conjugated diene monomer.

[0050] Here, "vinyl aromatic monomer unit" refers to the constituent unit of a polymer resulting from the polymerization of vinyl aromatic monomers, and its structure is a molecular structure in which the two carbon atoms of a substituted ethylene group derived from a substituted vinyl group are bonded. Similarly, "conjugated diene monomer unit" refers to the constituent unit of a polymer resulting from the polymerization of conjugated dienes, and its structure is a molecular structure in which the two carbon atoms of an olefin derived from a conjugated diene monomer are bonded.

[0051] In component (D) relating to this disclosure, "mainly" means that the copolymer block contains 50 mol% or more, preferably 60 mol% or more, and more preferably 65 mol% or more, of monomer units derived from a conjugated diene monomer (or vinyl aromatic monomer). For example, a block mainly consisting of conjugated diene monomer units means that the block contains 50 mol% or more, preferably 60 mol% or more, and more preferably 65 mol% or more, of monomer units derived from a conjugated diene monomer.

[0052] The vinyl aromatic monomer in component (D) of this disclosure is not particularly limited, and examples include vinyl aromatic compounds such as styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N,N-dimethyl-p-aminoethylstyrene, and N,N-diethyl-p-aminoethylstyrene. These may be used individually or in combination of two or more. Among these, styrene is preferred from an economic standpoint.

[0053] The conjugated diene monomer in component (D) of this disclosure is a diolefin having one pair of conjugated double bonds, and examples include 1,3-butadiene (butadiene), 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, and 1,3-hexadiene. Among these, butadiene and isoprene are preferred from the viewpoint of economy. These may be used individually or in combination of two or more.

[0054] The arrangement of each block in component (D) relating to this disclosure is not particularly limited, and a suitable arrangement can be adopted as appropriate. For example, if a polymer block consisting of vinyl aromatic monomer units is represented by S, and a polymer block consisting of units in which at least a portion of conjugated diene monomer units is hydrogenated is represented by B, then the hydrogenated products of this block copolymer are SB, S(BS) n1 (Here, n1 represents an integer from 1 to 3.) S(BSB) n2 Linear block copolymers represented by (where n² represents an integer between 1 and 2), etc., and (SB) n3 Copolymers represented by X (where n3 represents an integer from 3 to 6, and X represents a coupling agent residue such as silicon tetrachloride, tin tetrachloride, or a polyepoxy compound) are examples. Among these, linear block copolymers of type 2 (diblock) of SB, type 3 (triblock) of SBS, and type 4 (tetrablock) of SBSB are preferred.

[0055] Here, polymer block B may be a polymer block consisting only of conjugated diene monomer units, or a polymer block mainly containing conjugated diene monomer units and also containing vinyl aromatic monomer units (conjugated diene monomer units and vinyl aromatic monomer units copolymerized), and in either case, at least a portion of the conjugated diene monomer units is hydrogenated.

[0056] The content of vinyl aromatic monomer units in component (D) relating to this disclosure can be measured by nuclear magnetic resonance spectroscopy (NMR). The content of vinyl aromatic monomer unit blocks in component (D) relating to this disclosure is preferably 10% by mass or more, and more preferably 10 to 40% by mass, from the viewpoint of mechanical strength. Here, the content of vinyl aromatic compound polymer blocks in component (D) is defined by the following formula, using the mass of vinyl aromatic compound polymer blocks obtained by a method of oxidative decomposition of the copolymer before hydrogenation with tert-butyl hydroperoxide using osmium tetroxide as a catalyst (the method described in IM Kolthoff, et al., J. Polym. Sci. 1, 429 (1946), hereinafter also referred to as the "osmium tetroxide decomposition method") (where vinyl aromatic compound polymers with an average degree of polymerization of about 30 or less are excluded). Vinyl aromatic compound polymer block content (mass%) = (Mass of vinyl aromatic compound polymer blocks in copolymer before hydrogenation / Mass of copolymer before hydrogenation) × 100

[0057] If multiple polymer blocks exist in component (D) of this disclosure, their molecular weights, compositions, and other structural properties may be the same or different. For example, component (D) may contain a hydrogenated copolymer block containing conjugated diene monomer units and vinyl aromatic monomer units, and a hydrogenated copolymer block mainly composed of conjugated diene monomer units. The boundaries and ends of each block do not necessarily need to be clearly distinguishable. The distribution of vinyl aromatic monomer units in each polymer block is not particularly limited and may be uniform, tapered, stepped, convex, or concave. Furthermore, crystalline portions may be present in the polymer block.

[0058] The distribution of vinyl units of conjugated diene monomer units in each polymer block within component (D) of this disclosure is not particularly limited, and for example, the distribution may be biased. Methods for controlling the distribution of vinyl units include adding a vinylizing agent during polymerization and changing the polymerization temperature. Furthermore, the distribution of hydrogenation rates of conjugated diene monomer units may also be biased. The distribution of hydrogenation rates can be controlled by changing the distribution of vinyl units, or by copolymerizing isoprene and butadiene and then hydrogenating using a hydrogenation catalyst described later, utilizing the difference in hydrogenation rates between isoprene units and butadiene units.

[0059] Component (D) relating to this disclosure is characterized in that, from the viewpoint of heat resistance, aging resistance, and weather resistance, preferably 75 mol% or more, more preferably 85 mol% or more, and even more preferably 97 mol% or more of the unsaturated bonds contained in the conjugated diene monomer unit before hydrogenation are hydrogenated. The hydrogenation catalyst used is not particularly limited and is generally known. (1) Supported heterogeneous hydrogenation catalysts in which metals such as Ni, Pt, Pd, Ru are supported on carbon, silica, alumina, diatomaceous earth, etc. (2) A so-called Ziegler-type hydrogenation catalyst using organic acid salts such as Ni, Co, Fe, Cr or transition metal salts such as acetylacetone salt and a reducing agent such as organoaluminum, (3) Homogeneous hydrogenation catalysts such as organometallic compounds like Ti, Ru, Rh, and Zr, or so-called organometallic complexes, can be used.

[0060] Specific hydrogenation catalysts that can be used include those described in Japanese Patent Publication No. 42-008704, Japanese Patent Publication No. 43-006636, Japanese Patent Publication No. 63-004841, Japanese Patent Publication No. 01-037970, Japanese Patent Publication No. 01-053851, Japanese Patent Publication No. 02-009041, etc. Among these, preferred hydrogenation catalysts include reducing organometallic compounds such as titanocene compounds.

[0061] Examples of titanocene compounds include those described in Japanese Patent Publication No. 08-109219, and specific examples include compounds having at least one ligand with a (substituted) cyclopentadienyl skeleton, an indenyl skeleton, or a fluorenyl skeleton, such as biscyclopentadienyl titanium dichloride and monopentamethylcyclopentadienyl titanium trichloride. Examples of reducing organometallic compounds include organoalkali metal compounds such as organolithium, organomagnesium compounds, organoaluminum compounds, organoboron compounds, and organozinc compounds.

[0062] The polymerization method for the block copolymer before hydrogenation in component (D) relating to this disclosure is not particularly limited, and known methods may be employed. Examples include the methods described in Japanese Patent Publication No. 36-019286, Japanese Patent Publication No. 43-017979, Japanese Patent Publication No. 46-032415, Japanese Patent Publication No. 49-036957, Japanese Patent Publication No. 48-002423, Japanese Patent Publication No. 48-004106, Japanese Patent Publication No. 56-028925, Japanese Unexamined Patent Publication No. 59-166518, Japanese Unexamined Patent Publication No. 60-186577, etc.

[0063] If necessary, component (D) may have a polar group. Examples of polar groups include hydroxyl groups, carboxyl groups, carbonyl groups, thiocarbonyl groups, acid halide groups, acid anhydride groups, thiocarboxylic acid groups, aldehyde groups, thioaldehyde groups, carboxylic acid ester groups, amide groups, sulfonic acid groups, sulfonic acid ester groups, phosphoric acid groups, phosphoric acid ester groups, amino groups, imino groups, nitrile groups, pyridyl groups, quinoline groups, epoxy groups, thioepoxy groups, sulfide groups, isocyanate groups, isothiocyanate groups, silicon halide groups, alkoxysilicon groups, tin halide groups, boronic acid groups, boron-containing groups, boronic acid bases, alkoxytin groups, and phenyltin groups.

[0064] The vinyl bond content in the conjugated diene monomer units in the block copolymer before hydrogenation of component (D) relating to this disclosure is preferably 5 mol% or more from the viewpoint of flexibility and scratch resistance, and preferably 70 mol% or less from the viewpoint of productivity, elongation at break, and scratch resistance. The vinyl bond content in the conjugated diene monomer units is more preferably 10 to 50 mol%, even more preferably 10 to 30 mol%, and still more preferably 10 to 25 mol%. In this context, vinyl bond content refers to the proportion of 1,2- and 3,4-bonded structures within the 1,2-, 3,4-, and 1,4-bonded structures of the conjugated diene before hydrogenation. Vinyl bond content can be measured by NMR.

[0065] The weight-average molecular weight of component (D) before crosslinking is not particularly limited, but from the viewpoint of scratch resistance, it is preferably 50,000 or more, from the viewpoint of moldability, it is preferably 400,000 or less, and more preferably 50,000 to 300,000. The molecular weight distribution (Mw / Mn: weight-average molecular weight / number-average molecular weight) is not particularly limited, but from the viewpoint of scratch resistance, it is preferably close to 1. The weight-average molecular weight and number-average molecular weight can be determined by gel permeation chromatography (GPC; Shimadzu Corporation, instrument name "LC-10") using tetrahydrofuran (1.0 mL / min) as the solvent and an oven temperature of 40°C, with columns: TSKgelGMHXL (4.6 mm ID × 30 cm, 2 columns). The weight-average molecular weight (Mw), number-average molecular weight (Mn), and molecular weight distribution (Mw / Mn) are calculated as polystyrene-equivalent molecular weight.

[0066] <Polyorganosiloxane (E)> The structure of polyorganosiloxane (E), which may be included in the thermoplastic elastomer composition of this disclosure (hereinafter sometimes referred to as "component (E)"), is not particularly limited, but from the viewpoint of abrasion resistance and tactile feel, it is preferable to have a linear, branched, or crosslinked polymer structure.

[0067] Component (E) relating to this disclosure is not particularly limited and known components may be used. Preferred polyorganosiloxanes are polymers containing siloxane units having substituents such as alkyl groups, vinyl groups, and aryl groups, and among these, polyorganosiloxanes having alkyl groups are particularly preferred, and polyorganosiloxanes having methyl groups are more preferred.

[0068] Specific examples of polyorganosiloxanes having methyl groups include, for example, polydimethylsiloxane, polymethylphenylsiloxane, and polymethylhydrogensiloxane. Among these, polydimethylsiloxane is preferred.

[0069] The kinematic viscosity of component (E) relating to this disclosure is not particularly limited, but from the viewpoint of abrasion resistance and scratch resistance, it is preferable that the kinematic viscosity (25°C) specified in JIS Z8803 is 5,000 centistokes (cSt) or higher. Furthermore, from the viewpoint that the dispersibility of component (E) in the resulting thermoplastic elastomer composition tends to improve, resulting in a superior appearance and further improved quality stability during melt extrusion, it is preferable that the kinematic viscosity of component (E) is less than 3 million cSt. More preferably, the kinematic viscosity of component (E) is 10,000 cSt or more and less than 3 million cSt, and even more preferably 50,000 cSt or more and less than 3 million cSt.

[0070] Thermoplastic elastomer composition The thermoplastic elastomer composition of this disclosure contains the above-mentioned propylene polymer (A), the above-mentioned olefin copolymer (B), and the above-mentioned softener (C), wherein the above-mentioned olefin copolymer (B) contains the above-mentioned ethylene-α-olefin copolymer (B1) and the above-mentioned ethylene-propylene-non-conjugated polyene copolymer (B2), the content of the above-mentioned ethylene-α-olefin copolymer (B1) in the above-mentioned olefin copolymer (B) is 0 to 99% by mass, and the content of the above-mentioned ethylene-propylene-non-conjugated polyene copolymer (B2) is 1 to 100% by mass [provided that the total content of (B1) and (B2) is 100% by mass]. The propylene polymer (A) content is 25 to 300 parts by mass, preferably 25 to 250 parts by mass, more preferably 30 to 230 parts by mass, and even more preferably 35 to 200 parts by mass, per 100 parts by mass of the olefin copolymer (B), and the softener (C) content is more than 120 parts by mass and 300 parts by mass or less, preferably 120 parts by mass, per 100 parts by mass of the olefin copolymer (B) Mass part More than 290 parts by mass or less, more preferably 120 Mass part More than 270 parts by mass or less, more preferably 120 Mass part This is a thermoplastic elastomer composition containing more than 250 parts by mass or less.

[0071] The thermoplastic elastomer composition of this disclosure contains the above-mentioned component (A), component (B), and component (C) within the above-mentioned range, thereby providing a composition with excellent fluidity, flexibility, and tactile properties.

[0072] When the thermoplastic elastomer composition of this disclosure includes the above-mentioned hydrogenated block copolymer (D) in addition to the above-mentioned components, a composition with excellent scratch resistance can be obtained. If the thermoplastic elastomer composition of this disclosure contains component (D), the content of component (D) is preferably in the range of 30 to 350 parts by mass, more preferably 40 to 330 parts by mass, and even more preferably 50 to 300 parts by mass, per 100 parts by mass of component (B).

[0073] When the thermoplastic elastomer composition of this disclosure includes the above-mentioned polyorganosiloxane (E) in addition to the above-mentioned components, a composition with excellent abrasion resistance can be obtained. If the thermoplastic elastomer composition of this disclosure contains component (E), the content of the polyorganosiloxane in the composition is preferably in the range of 0.5 to 10% by mass, more preferably 1 to 8% by mass, and even more preferably 1 to 4% by mass.

[0074] The thermoplastic elastomer composition of this disclosure preferably contains a crosslinking agent (F) [hereinafter sometimes referred to as "component (F)"] as needed. Component (F) relating to this disclosure acts as a crosslinking initiator for components (A), (B), and (D), which are components of the thermoplastic elastomer composition of the present invention, by dynamically heat-treating the thermoplastic elastomer composition of the present invention. Component (F) may be a phenolic resin-based crosslinking agent or an organic peroxide-based crosslinking agent, but an organic peroxide-based crosslinking agent is preferred.

[0075] <Organic peroxide> Specific examples of organic peroxides that can be used as organic peroxide crosslinking agents include 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-hexylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)cyclododecane, 1,1-bis(t-butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)octane, n-butyl-4,4-bis(t-butylperoxy)butane, Peroxyketals such as n-butyl-4,4-bis(t-butylperoxy)valerate; dialkylperoxides such as di-t-butylperoxide, dicumylperoxide, t-butylcumylperoxide, α,α'-bis(t-butylperoxy-m-isopropyl)benzene, α,α'-bis(t-butylperoxy)diisopropylbenzene, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, and 2,5-dimethyl-2,5-bis(t-butylperoxy)hexine-3; acetylperoxide Diacyl peroxides such as isobutyryl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, m-trioyl peroxide; t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxy-2-ethylhexanoate, t-butyl peroxylaurate, t-butyl peroxybenzoate, di-t-butyl Examples include peroxyesters such as peroxyisophthalate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-butylperoxymaleic acid, t-butylperoxyisopropyl carbonate, and cumylperoxyoctate; and hydroperoxides such as t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, and 1,1,3,3-tetramethylbutylperoxide.

[0076] Among these components (F), 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, and 2,5-dimethyl-2,5-bis(t-butylperoxy)hexyn-3 are preferred from the viewpoint of thermal decomposition temperature and crosslinking performance.

[0077] The component (F) relating to this disclosure may be used alone or in combination of two or more types. If the thermoplastic elastomer composition of this disclosure contains component (F), its content is preferably 2 to 10 parts by mass, more preferably 2 to 8 parts by mass, per 100 parts by mass of component (B), from the viewpoint of moldability. If the thermoplastic elastomer composition of this disclosure contains component (F), the following crosslinking aid (G) may be used in combination.

[0078] <Crosslinking agent (G)> The crosslinking aid (G) relating to this disclosure includes various known crosslinking aids, specifically monofunctional monomers and polyfunctional monomers. Such crosslinking aids can control the rate of the crosslinking reaction. As monofunctional monomers, for example, radically polymerizable vinyl monomers are preferred, and examples include aromatic vinyl monomers, unsaturated nitrile monomers such as acrylonitrile and methacrylonitrile, acrylic acid ester monomers, methacrylic acid ester monomers, acrylic acid monomers, methacrylic acid monomers, maleic anhydride monomers, and N-substituted maleimide monomers.

[0079] Specific examples of monofunctional monomers include, for example, styrene, methylstyrene, chloromethylstyrene, hydroxystyrene, tert-butoxystyrene, acetoxystyrene, chlorostyrene, acrylonitrile, methacrylonitrile, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, maleic anhydride, methyl maleic anhydride, 1,2-dimethyl maleic anhydride, ethyl maleic anhydride, phenyl maleic anhydride, N-methyl maleimide, N-ethyl maleimide, N-cyclohexyl maleimide, N-lauryl maleimide, and N-cetyl maleimide. Among these, styrene, acrylonitrile, methacrylonitrile, methyl acrylate, maleic anhydride, and N-methyl maleimide are preferred from the viewpoint of ease of reaction and versatility. These monofunctional monomers may be used individually or in combination of two or more.

[0080] A polyfunctional monomer is a monomer having multiple radically polymerizable functional groups, and a monomer having a vinyl group is preferred. The number of functional groups in a polyfunctional monomer is preferably two or three. Specific examples of polyfunctional monomers include divinylbenzene, triallyl isocyanurate, triallyl cyanurate, diacetone diacrylamide, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diisopropenylbenzene, p-quinone dioxime, p,p'-dibenzoylquinone dioxime, phenylmaleimide, allyl methacrylate, N,N'-m-phenylenebismaleimide, diallyl phthalate, tetraallyloxyethane, and 1,2-polybutadiene, with divinylbenzene and triallyl isocyanurate being more preferred. These polyfunctional monomers may be used individually or in combination of two or more.

[0081] If the thermoplastic elastomer composition of this disclosure contains a crosslinking aid (G), it is preferably 1 to 50 parts by mass, more preferably 1 to 30 parts by mass, per 100 parts by mass of component (F).

[0082] <Method for producing thermoplastic elastomer compositions and their physical properties> By dynamically crosslinking the thermoplastic elastomer composition of this disclosure, components (A) and (B) contained in the thermoplastic elastomer composition, and optionally, components (D) if present, at least a portion of said components, are crosslinked. When performing dynamic crosslinking, it is preferable to perform dynamic heat treatment in the presence of component (F), or in the presence of component (F) and the crosslinking aid.

[0083] In this disclosure, "dynamic heat treatment" means kneading in a molten state. Furthermore, the thermoplastic elastomer composition of this disclosure may be referred to as "Composition 1" before dynamic heat treatment, and as "Composition 2" after dynamic heat treatment.

[0084] The dynamic heat treatment in this disclosure is preferably carried out in a closed apparatus and preferably in an inert gas atmosphere such as nitrogen or carbon dioxide. The heat treatment temperature is in the range of 300°C or less from the melting point of component (A), and is usually 150 to 270°C, preferably 170 to 250°C. The mixing time is usually 1 to 20 minutes, preferably 1 to 10 minutes. The shear force applied is usually 10 to 50,000 s in terms of shear rate. -1 Preferably 100 to 10,000 seconds -1 It is within the range.

[0085] The Shore A hardness (10-second value) of composition 2 (according to the measurement method of JIS K 6253) is preferably 50 or higher, more preferably 50 to 80. When the Shore A hardness (10-second value) of composition 2 is within the aforementioned range, a molded article with aesthetic appeal such as a pleasant feel and a high-quality appearance, as well as scratch resistance, can be easily formed. The Shore A hardness (10-second value) can be measured specifically by the method described in the following examples.

[0086] The melt flow rate of composition 2 (according to the measurement method of JIS K 7210, 230°C, 1.2 kg load) is preferably 30 g / 10 min or more, and more preferably 55 g / 10 min or more, from the standpoint of producing a composition with excellent moldability.

[0087] In addition to the above-mentioned component (A), the thermoplastic elastomer composition of this disclosure may also contain inorganic fillers, plasticizers, and other additives. Examples of inorganic fillers include calcium carbonate, magnesium carbonate, silica, carbon black, glass fiber, titanium dioxide, clay, mica, talc, magnesium hydroxide, and aluminum hydroxide. Examples of plasticizers include polyethylene glycol and phthalate esters such as dioctyl phthalate (DOP).

[0088] Other additives include, for example, organic and inorganic pigments such as carbon black, titanium dioxide, or phthalocyanine black; heat stabilizers such as 2,6-di-t-butyl-4-methylphenol and n-octadecyl-3-(3,5'-di-t-butyl-4-hydroxyphenyl)propionate; antioxidants such as trisnonylphenyl phosphite and distearyl pentaerythritol diphosphite; UV absorbers such as 2-(2'-hydroxy-5'methylphenyl)benzotriazole and 2,4-dihydroxybenzophenone; bis-[2,2,6,6-tetramethyl-4-piperidinyl]sebacate, tetramethyl Examples include light stabilizers such as (2,2,6,6-tetramethyl-4-piperidinyl)-1,2,3,4-butanetetracarboxylate; flame retardants such as ammonium polyphosphate, trioctyl phosphate, and magnesium hydroxide; silicone oils such as dimethyl silicone oil and methylphenyl silicone oil; antiblocking agents such as stearic acid amide and erucic acid amide; foaming agents such as sodium bicarbonate and N,N'-dinitrosopentamethylenetetramine; antistatic agents such as palmitate monoglyceride and stearate monoglyceride; and antibacterial agents such as silver ion-supported zeolite and thiosulfite silver complexes.

[0089] ≪Molded product≫ The molded articles relating to this disclosure are not particularly limited as long as they include the thermoplastic elastomer composition of this disclosure, and are molded using any known molding method depending on the application. Examples of molding methods include press molding, injection molding, extrusion molding, calendering, hollow molding, vacuum molding, and compression molding. From the viewpoint of productivity and the ability to easily form complex shapes, injection molded articles formed using injection molding are preferred. The thermoplastic elastomer composition disclosed herein has excellent scratch resistance while possessing hardness that satisfies the required performance, and is not particularly limited in its applications. For example, as a molded article, it is suitable for various known applications such as automotive parts, civil engineering and construction materials, electrical and electronic components, sanitary products, films and sheets, foams, and artificial leather, and is particularly suitable for use as an automotive part such as automotive interior parts and as a surface material such as artificial leather.

[0090] <Automotive parts> Examples of automotive parts that can be used with the molded articles of this disclosure include weatherstrips, headliners, interior seats, bumper moldings, side moldings, air spoilers, air duct hoses, cup holders, handbrake grips, shift knob covers, seat adjustment knobs, flapper door seals, wire harness grommets, rack and pinion boots, suspension cover boots, glass guides, inner beltline seals, roof guides, trunk lid seals, molded quarter window gaskets, corner moldings, glass enclosures, hood seals, glass run channels, secondary seals, various gaskets, bumper parts, body panels, side shields, glass run channels, instrument panel surfaces, door surfaces, headliners, weatherstrip materials, hoses, steering wheels, boots, wire harness covers, seat adjuster covers, etc. Among these, the thermoplastic elastomer composition of this disclosure is particularly preferred because it can improve texture and feel.

[0091] <Civil engineering / building materials supplies> Examples of civil engineering and construction materials that can be used with the molded articles relating to this disclosure include civil engineering materials and construction materials such as ground improvement sheets, water intake panels, and noise prevention walls, as well as various gaskets and sheets for civil engineering and construction, waterproofing materials, joint materials, and building window frames. Among these, the thermoplastic elastomer composition relating to this disclosure is particularly preferred because it can improve texture and feel.

[0092] <Electrical and Electronic Components> Examples of electrical and electronic components that can be used in the molded articles relating to this disclosure include, for example, wire insulation materials, connectors, caps, plugs, and other electrical and electronic components. Among these, the thermoplastic elastomer composition relating to this disclosure is particularly preferred because it can improve texture and feel.

[0093] <Household goods> Examples of lifestyle products to which the molded articles relating to this disclosure can be used include sports equipment such as sports shoe soles, ski boots, tennis rackets, ski bindings, and bat grips, as well as miscellaneous goods such as pen grips, toothbrush grips, hairbrushes, fashion belts, various caps, and shoe insoles. Among these, the thermoplastic elastomer composition relating to this disclosure is particularly preferred because it can improve texture and feel.

[0094] <Film / Sheet> Examples of films and sheets that can be used in molded articles according to this disclosure include intravenous fluid bags, medical containers, automotive interior and exterior materials, beverage bottles, clothing cases, food packaging materials, food containers, retort containers, pipes, transparent substrates, sealants, and the like. Among these, the thermoplastic elastomer composition of this disclosure is particularly preferred because it can improve texture and feel.

[0095] <Artificial leather> Examples of artificial leathers that can be used in molded articles according to this disclosure include chair upholstery, bags, school bags, sports shoes such as athletic shoes, marathon shoes, and running shoes, clothing such as jackets and coats, belts, sashes, ribbons, notebook covers, book covers, keychains, pen cases, wallets, business card holders, and pass cases. Among these, the thermoplastic elastomer composition of this disclosure is particularly preferred because it can improve the texture and feel of the leather. [Examples]

[0096] The following disclosure applies to the examples provided. , reference example The present disclosure is not limited to these examples, although further details will be provided by the comparative examples. Unless otherwise specified in these examples, the numerical values ​​are based on mass. Examples , reference example The polymers used in the comparative examples are shown below.

[0097] [Propylene polymer (A)] (1) As the propylene polymer (A), a propylene homopolymer (A-1) [manufactured by Sun Allomer Co., Ltd., trade name Sun Allomer (registered trademark) PL400A] with an MFR of 2.0 g / 10 min at 230°C and a 2.16 kg load was used.

[0098] [Olefin copolymer (B1)] (1) As the ethylene-α-olefin copolymer (B1-1), ethylene-1-octene copolymer (manufactured by Dow Chemical, trade name "Engage 8842") was used. The copolymer had an ethylene content of 55% by mass and an octene content of 45% by mass, and the MFR at 190°C and a 2.16 kg load was 1.0 g / 10 min.

[0099] [Ethylene-α-olefin-non-conjugated polyene copolymer (B2)] (1) As the ethylene-α-olefin-non-conjugated polyene copolymer (B2-1), ethylene-propylene-5-ethylidene-2-norbornene (ENB) copolymer was used. The ethylene content of this copolymer was 70% by mass, and the ENB content was 4.9% by mass.

[0100] [Softener (C)] (1) As a softening agent (C-1), paraffin-based oil (manufactured by Idemitsu Kosan Co., Ltd., product name "Diana Process Oil PW-100") was used.

[0101] [Hydrogenated block copolymer (D)] (1) Hydrogenated styrene-butadiene block copolymer (manufactured by Asahi Kasei Corporation, SOE trade name S1605) was used as the hydrogenated material (D-1) of the block copolymer. (2) Hydrogenated styrene-butadiene block copolymer (manufactured by Asahi Kasei Corporation, SOE trade name S1606) was used as the hydrogenated material (D-2) of the block copolymer.

[0102] [Polyorganosiloxane (E)] As the polyorganosiloxane (E-1), a masterbatch consisting of 50% by mass of dimethylsiloxane and 50% by mass of polypropylene (manufactured by DuPont-Toray Specialty Materials, product name "MB50-001") was used.

[0103] [Organic peroxide (F)] As the organic peroxide (F-1), 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane (manufactured by Nippon Oil & Fats Co., Ltd., trade name "Perhexa 25B") was used.

[0104] [Crosslinking agent (G)] (1) Divinylbenzene (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the crosslinking aid (G-1).

[0105] [Example 1~ 3. Reference example 4~ 5. Comparative Examples 1-5] A twin-screw extruder (30 mmφ, L / D=74; manufactured by Kobe Steel, Ltd., "KTX-30") with an oil inlet in the center of the barrel was used as the extruder. A two-run screw with kneading sections before and after the inlet was used as the screw. Polymers other than the softener (C-1) listed in Table 1 were mixed together in the parts by mass shown in Table 1, and then introduced into the twin-screw extruder (cylinder temperature 200°C) using a quantitative feeder. Subsequently, the amount of softener (C-1) shown in Table 1 was injected by pump from the inlet in the center of the extruder, and melt extrusion kneading was performed to obtain a dynamically heat-treated thermoplastic elastomer composition. The physical properties of the obtained thermoplastic elastomer composition were evaluated by the following method. The results are shown in Table 1.

[0106] [Flowability of thermoplastic elastomer compositions] The fluidity of the thermoplastic elastomer composition was evaluated by the melt flow rate (MFR). MFR was measured at 230°C under a 1.2 kg load, in accordance with JIS K7210. The measurement results were evaluated according to the following criteria. (Evaluation Criteria) ◎:55g / 10 minutes or more ○: 30g / 10 minutes or more, less than 55g / 10 minutes ×: 30g / less than 10 minutes

[0107] [Flexibility (Shore hardness measurement)] In accordance with JIS K6253, a 2 mm thick press sheet was prepared from a thermoplastic elastomer composition. Three of these press sheets were stacked to obtain a 6 mm thick laminated sheet. The Shore A hardness of this laminated sheet was measured using a Shore A hardness tester, and the value after 10 seconds (10s value) was determined as the Shore hardness. A Shore hardness of 50-80 indicates excellent flexibility.

[0108] [Stickyness (coefficient of kinetic friction (μk)] Injection molding of a thermoplastic elastomer composition was performed using a flat mold measuring 15 cm in length and 9 cm in width, with a leather-grain finish. The injection molding machine used was the "M150CL-DM" manufactured by Meiki Seisakusho Co., Ltd. The molding conditions were a resin temperature of 220°C and a mold temperature of 40°C. The dynamic friction coefficient of the molded body was evaluated using the measurement method described below. Using a static / dynamic friction measuring instrument (Trinity Labs, product name "TL201Ts"), the dynamic friction coefficient of the sample surface was measured by bringing a tactile contact into contact with the molded sample under the conditions of a sliding speed of 100 mm / sec, a vertical load of 50 gf, and a sliding distance of 60 mm. The measurement results were evaluated according to the following criteria. (Evaluation Criteria) ◎: 0.60 μk or less 〇: More than 0.60μk and less than 0.80μk ×: More than 0.80μk

[0109] [Table 1]

[0110] [Table 2]

[0111] As shown in Table 1, Examples 1 to 3 and Reference Example 4~The thermoplastic elastomer composition 5 exhibited excellent fluidity, flexibility, and surface feel, and was confirmed to fully satisfy the performance requirements for a surface material of the present invention, resulting in a favorable overall evaluation. On the other hand, in Comparative Examples 1, 3, and 5, molded products with strong stickiness and excellent tactile properties were not obtained. In Comparative Examples 2 and 4, the MFR was low and did not satisfy the high fluidity required for the surface material. From the above, it was found that the compositions of Comparative Examples 1 to 5 could not achieve both fluidity and tactile properties, and the overall evaluation was poor.

Claims

1. A propylene polymer (A) and Olefin copolymer (B) and Softener (C), It contains, The olefin copolymer (B) is An ethylene-α-olefin copolymer (B1) comprising ethylene and a unit derived from an α-olefin that is 1-butene or 1-octene, Ethylene-propylene-non-conjugated polyene copolymer (B2) and It contains, The olefin copolymer (B) contains 25 to 75% by mass of the ethylene-α-olefin copolymer (B1), and the ethylene-propylene-non-conjugated polyene copolymer (B2) contains 25 to 75% by mass [provided that the total content of (B1) and (B2) is 100% by mass]. The content of the propylene polymer (A) is 25 to 300 parts by mass per 100 parts by mass of the olefin copolymer (B), and A thermoplastic elastomer composition in which the content of the softening agent (C) is more than 120 parts by mass and 300 parts by mass or less, per 100 parts by mass of the olefin copolymer (B).

2. The thermoplastic elastomer composition according to Claim 1, wherein the content of the softening agent (C) is more than 120 parts by mass and 290 parts by mass or less, based on 100 parts by mass of the olefin copolymer (B).

3. The thermoplastic elastomer composition according to claim 1 or 2, further comprising a hydrogenated block copolymer (D).

4. The thermoplastic elastomer composition according to claim 3, wherein the content of the hydrogenated substance (D) in the block copolymer is 30 to 350 parts by mass per 100 parts by mass of the olefin-based copolymer (B).

5. The thermoplastic elastomer composition according to any one of claims 1 to 4, wherein the content of the propylene polymer (A) is 25 to 250 parts by mass per 100 parts by mass of the olefin copolymer (B).

6. The thermoplastic elastomer composition according to any one of claims 1 to 5, wherein at least a portion of the olefin copolymer (B) is crosslinked.

7. An injection-molded article comprising the thermoplastic elastomer composition according to any one of claims 1 to 6.

8. Automotive interior part comprising an injection-molded body as described in claim 7.

9. A propylene polymer (A) and Olefin copolymer (B) and Softener (C), It contains, The olefin copolymer (B) is An ethylene-α-olefin copolymer (B1) comprising ethylene and a unit derived from an α-olefin that is 1-butene or 1-octene, Ethylene-propylene-non-conjugated polyene copolymer (B2) and It contains, The olefin copolymer (B) contains 25 to 75% by mass of the ethylene-α-olefin copolymer (B1), and the ethylene-propylene-non-conjugated polyene copolymer (B2) contains 25 to 75% by mass [provided that the total content of (B1) and (B2) is 100% by mass]. The content of the propylene polymer (A) is 25 to 300 parts by mass per 100 parts by mass of the olefin copolymer (B), and A method for producing a thermoplastic elastomer composition, wherein the content of the softening agent (C) is more than 120 parts by mass and 300 parts by mass or less, per 100 parts by mass of the olefin copolymer (B), The manufacturing method includes a step of dynamically heat-treating the propylene polymer (A), the olefin copolymer (B), and the softener (C) in the presence of a crosslinking agent (F). A method for producing a thermoplastic elastomer composition.

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