Thermoplastic elastomer composition, molded body thereof, and use thereof

Abstract

The objective of this invention is to provide a highly transparent thermoplastic elastomer composition and its molded form that can be suitably used for applications such as interior trim materials without compromising the appearance (designability, texture molding properties, etc.) and moldability of conventional interior trim materials. This thermoplastic elastomer composition comprises: 100 parts by weight of an ethylene-α-olefin-nonconjugated polyene copolymer (A), and an unobservable melting point (Tm). B ) or melting point (Tm) B ) Soft propylene copolymer (B) with a temperature below 115℃, 20-5,000 parts by weight, melting point (Tm) C The soft propylene copolymer (B) comprises 10 to 500 parts by weight of a crystalline polyolefin (C) heated to or above 115°C, 0 to 70 parts by weight of a softener (D), and 0.01 to 10 parts by weight of a crosslinking agent (E). The soft propylene copolymer (B) also satisfies all of the following requirements (b-1) to (b-2): (b-1) it contains 90 to 50 mol% of constituent units from propylene, 0 to 30 mol% of constituent units from 1-butene, and 5 to 30 mol% of constituent units from ethylene; (b-2) the molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is in the range of 1.0 to 3.5.

Description

Technical Field

[0001] This invention relates to thermoplastic elastomer compositions, molded articles thereof, and their uses. Background Technology

[0002] In car cabins, interior materials such as leather-like trim panels are sometimes used to create a sense of luxury. Furthermore, in recent years, cars have incorporated a wide variety of displays and functional components into the driver's dashboard. These include traditional instruments such as speedometers, tachometers, and fuel level indicators; switches for air conditioning, windows, and door locks; displays and controls for the vehicle navigation system; and various external monitors, lighting, and decorative elements.

[0003] When a display device or control unit is installed under the interior trim material, the interior trim material needs to have a degree of transparency that allows visual recognition of the display reflected on the trim panel when the light source of the display device or control unit is emitting light. On the other hand, when the light source is not emitting light (non-illuminating), it needs to have a high degree of design (a sense of luxury, etc.).

[0004] Patent Document 1 discloses a thermoplastic elastomer composition for use as a sealing strip, comprising 10 to 60 parts by weight of a non-crosslinked crystalline polyolefin resin (A), 1 to 20 parts by weight of a propylene-1-butene-ethylene random copolymer (B), 89 to 20 parts by weight of a partially or completely crosslinked ethylene-α-olefin-non-conjugated polyene copolymer rubber (C) composed of ethylene, α-olefins with 3 to 20 carbon atoms, and non-conjugated polyenes, and a softener (D).

[0005] Patent document 2 discloses a thermoplastic resin composition with low viscosity and excellent formability, which comprises a thermoplastic elastomer resin (A), a polyolefin resin (B), a polypropylene resin (C), and an oil (D).

[0006] Patent document 3 discloses a thermoplastic elastomer composition, which is formed by mixing and crosslinking 1 to 98 parts by weight of isotactic polypropylene (A), 2 to 99 parts by weight of a propylene-ethylene (-α-olefin) random copolymer (B) with a propylene content of 45 to 89 mol%, an ethylene content of 10 to 25 mol%, and an α-olefin component unit content of 0 to 30 mol% as needed, and 2 to 1900 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer rubber (C).

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Publication No. 2009-215356

[0010] Patent Document 2: International Publication No. 2018 / 147391

[0011] Patent Document 3: Japanese Patent Application Publication No. 2009-73912 Summary of the Invention

[0012] The problem that the invention aims to solve

[0013] The thermoplastic elastomer compositions described in Patent Documents 1-3 do not achieve a balance between transparency and high design flexibility. Furthermore, it has been found that interior trim materials used in conventional display devices require further transparency. The inventors have also discovered that when olefin-based thermoplastic elastomers are used as interior trim materials (especially in display devices and decorative panels), the difference in refractive index among the components in the composition causes light refraction, making it impossible to achieve sufficient transparency for conventional interior trim materials.

[0014] The object of the present invention is to provide a highly transparent thermoplastic elastomer composition and its molded form that can be suitably used for interior trim materials and other applications without compromising the appearance (designability such as texture molding properties) and moldability of conventional interior trim materials.

[0015] Methods for solving problems

[0016] In order to solve the above-mentioned problems, the inventors conducted in-depth research. As a result, they found that a thermoplastic elastomer composition having the following structure can solve the above-mentioned problems, thereby completing the present invention. The present invention relates, for example, to the following [1] to [8].

[0017] [1] A thermoplastic elastomer composition comprising:

[0018] 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A)

[0019] Melting point (Tm) cannot be observed B ) or melting point (Tm) B 10-5,000 parts by weight of soft propylene copolymer (B) at temperatures below 115°C

[0020] Melting point (Tm) C The composition includes 10-500 parts by weight of crystalline polyolefin (C) with a temperature above 115°C, 0-200 parts by weight of plasticizer (D), and...

[0021] Crosslinking agent (E) 0.01 to 10 parts by weight.

[0022] [2] The thermoplastic elastomer composition as described in [1] above, the soft propylene copolymer (B) also satisfies all of the following requirements (b-1) to (b-2).

[0023] (b-1) contains 90–50 mol% of constituent units from propylene, 0–30 mol% of constituent units from 1-butene, and 5–30 mol% of constituent units from ethylene.

[0024] (b-2) The molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is in the range of 1.0 to 3.5.

[0025] [3] A thermoplastic elastomer composition comprising 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A) with an unobservable melting point (Tm). B ) or melting point (Tm) B 10-5,000 parts by weight of soft propylene copolymer (B) with a melting point (Tm) below 115℃ C The composition is obtained by dynamically crosslinking 10 to 500 parts by weight of a crystalline polyolefin (C) at a temperature above 115°C, 0 to 200 parts by weight of a softener (D), and 0.01 to 10 parts by weight of a crosslinking agent (E).

[0026] [4] The thermoplastic elastomer composition as described in [3] above, wherein at least a portion of the ethylene-α-olefin-nonconjugated polyene copolymer (A) is crosslinked.

[0027] [5] The thermoplastic elastomer composition as described in [3] or [4] above has a Shore A hardness (instantaneous value) (measured according to JISK 6253 by overlapping three sheets of 2 mm thickness) of 40 to 100.

[0028] [6] A molded body comprising the thermoplastic elastomer composition described in any one of [1] to [5] above.

[0029] [7] The molded body described in [6] above is an automotive interior skin material.

[0030] [8] As described in [7] above, the automotive interior skin material is an instrument panel, door trim, armrest or console.

[0031] Preferably, the present invention relates, for example, to the following (1) to (14).

[0032] 《1》A thermoplastic elastomer composition comprising:

[0033] 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A)

[0034] Melting point (Tm) cannot be observed B ) or melting point (Tm) B 20-5,000 parts by weight of soft propylene copolymer (B) at temperatures below 115°C

[0035] Melting point (Tm) C ) is 10-500 parts by weight of crystalline polyolefin (C) with a temperature above 115℃, 0-70 parts by weight of softener (D), and

[0036] Crosslinking agent (E) 0.01-10 parts by weight,

[0037] The aforementioned soft propylene copolymer (B) also satisfies all of the following requirements (b-1) to (b-2):

[0038] (b-1) contains 90–50 mol% of constituent units from propylene, 0–30 mol% of constituent units from 1-butene, and 5–30 mol% of constituent units from ethylene.

[0039] (b-2) The molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is in the range of 1.0 to 3.5.

[0040] 《2》The thermoplastic elastomer composition as described in 《1》, wherein the crosslinking agent (E) is an organic peroxide.

[0041] 《3》The thermoplastic elastomer composition as described in 《1》 or 《2》, has a melt flow rate (determined according to JIS K 7210, at 230°C and 10kg load) of 1 g / 10 min or more and less than 80 g / 10 min.

[0042] 4. The thermoplastic elastomer composition as described in any one of 1 to 3, wherein at least a portion of the ethylene-α-olefin-nonconjugated polyene copolymer (A) is crosslinked.

[0043] 《5》The thermoplastic elastomer composition as described in any one of 《1》 to 《4》, has a Shore A hardness (instantaneous value) (measured according to JIS K 6253, using three sheets of 2 mm thickness stacked together) of 40 to 100.

[0044] 《6》A molded body comprising any one of 《1》 to 《5》.

[0045] The molded body described in "7" as in "6" has an internal haze of less than 80%.

[0046] The molded body described in "8" or "6" or "7" has a total light transmittance of over 83%.

[0047] The molded body as described in any one of the following (6) to (8) is an automotive interior skin material.

[0048] 《10》As described in 《9》, the aforementioned automotive interior skin material is an instrument panel, door trim, armrest, or console.

[0049] 《11》A decorative panel, characterized in that it comprises a molded body containing a thermoplastic elastomer composition and a display device or operating part disposed at the lower part of the molded body.

[0050] The above thermoplastic elastomer composition comprises:

[0051] 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A)

[0052] Melting point (Tm) cannot be observed B ) or melting point (Tm) B 10-5,000 parts by weight of soft propylene copolymer (B) at temperatures below 115°C

[0053] Melting point (Tm) C ) is 10-500 parts by weight of crystalline polyolefin (C) at temperatures above 115℃.

[0054] 0-200 parts by weight of softener (D), and

[0055] Crosslinking agent (E) 0.01 to 10 parts by weight.

[0056] 《12》A method for manufacturing a thermoplastic elastomer composition, wherein the manufacturing method comprises:

[0057] The first step involves mixing 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A) with an unobservable melting point (Tm). B ) or melting point (Tm) B ) Soft propylene copolymer (B) with a temperature below 115℃, 0-5,000 parts by weight, melting point (Tm) C Composition (i) is obtained by dynamically crosslinking 10-500 parts by weight of a crystalline polyolefin (C) heated to above 115°C, 0-70 parts by weight of a softener (D), and 0.01-10 parts by weight of a crosslinking agent (E).

[0058] In the second step, 0 to 5,000 parts by weight of a soft propylene copolymer (B) are added to the above composition (i).

[0059] The total amount of the soft propylene copolymer (B) added in the first and second steps described above is 20 to 5,000 parts by weight.

[0060] The aforementioned soft propylene copolymer (B) also satisfies all of the following requirements (b-1) to (b-2):

[0061] (b-1) contains 90–50 mol% of constituent units from propylene, 0–30 mol% of constituent units from 1-butene, and 5–30 mol% of constituent units from ethylene.

[0062] (b-2) The molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is in the range of 1.0 to 3.5.

[0063] 《13》The method for manufacturing the thermoplastic elastomer composition as described in 《12》, wherein the amount of the soft propylene copolymer (B) added in the first step is 0 parts by mass.

[0064] Invention Effects

[0065] According to the present invention, it is possible to provide a highly transparent composition and its molded form that can be suitably used for purposes such as interior trim materials without compromising the appearance (designability such as texture molding properties) and moldability of conventional interior trim materials. Detailed Implementation

[0066] The embodiments of the present invention will be described in detail below, but the present invention is not limited to the configuration of the following embodiments. It should be noted that, in this specification, the numerical range represented by "~" means a range that includes the values ​​recorded before and after "~" as the lower limit and the upper limit.

[0067] Furthermore, when recording numerical ranges in stages, the upper and lower limits of each numerical range can be combined arbitrarily.

[0068] [Thermoplastic elastomer composition]

[0069] The thermoplastic elastomer composition of the present invention (hereinafter also referred to as "the composition") comprises 100 parts by weight of an ethylene-α-olefin-nonconjugated polyene copolymer (A) with a confirmed melting point (Tm). B ) or melting point (Tm) B 10-5,000 parts by weight of soft propylene copolymer (B) with a melting point (Tm) below 115℃ C The composition comprises 10-500 parts by weight of a crystalline polyolefin (C) with a temperature above 115°C, 0-200 parts by weight of a softener (D), and 0.01-10 parts by weight of a crosslinking agent (E), preferably containing 100 parts by weight of an ethylene-α-olefin-non-conjugated polyene copolymer (A) and a crosslinking agent with a confirmed melting point (Tm). B ) or melting point (Tm) B Soft propylene copolymer (B) with a temperature below 115℃, 20-5,000 parts by weight, melting point (Tm)C The composition comprises 10-500 parts by weight of a crystalline polyolefin (C) heated to or above 115°C, 0-70 parts by weight of a softener (D), and 0.01-10 parts by weight of a crosslinking agent (E). This composition may contain only these components and can be a mixture obtained by mixing only the components or a crosslinked composition obtained by crosslinking at least some of the components.

[0070] <Ethylene-α-olefin-nonconjugated polyene copolymer (A)>

[0071] There are no particular limitations on the ethylene-α-olefin-nonconjugated polyene copolymer (A) as long as it contains constituent units from ethylene, constituent units from α-olefin, and constituent units from nonconjugated polyene. For example, it can be synthesized by conventionally known methods of copolymerizing ethylene, α-olefin, and nonconjugated polyene.

[0072] The ethylene-α-olefin-nonconjugated polyene copolymer (A) contained in this composition may be one type or two or more types.

[0073] When the total content of constituent units from ethylene (hereinafter also referred to as "ethylene content") and constituent units from α-olefin (hereinafter also referred to as "α-olefin content") in the ethylene-α-olefin-nonconjugated polyene copolymer (A) is set to 100 mol%, the ethylene content is preferably 50 mol% or more, more preferably 50 to 95 mol%, even more preferably 55 to 85 mol%, and particularly preferably 60 to 83 mol%, from the perspective of easily obtaining molded articles with good molding appearance.

[0074] There are no particular limitations on the aforementioned α-olefins, but α-olefins with 3 to 20 carbon atoms are preferred. Specific examples of α-olefins with 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, 1-dodecene, 1-tetracene, 1-tetradecene, 1-pentadecadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecadecene, 1-eicosene, 9-methyl-1-decene, 11-methyl-1-dodecene, and 12-ethyl-1-tetradecene. One or more of these α-olefins may be used.

[0075] The preferred α-olefins are propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene, with propylene being more preferred.

[0076] When the total ethylene content and α-olefin content in the ethylene-α-olefin-nonconjugated polyene copolymer (A) are set to 100 mol%, considering that it is easy to obtain molded articles with good molding appearance, the α-olefin content is preferably 50 mol% or less, more preferably 5 to 50 mol%, even more preferably 15 to 45 mol%, and particularly preferably 17 to 40 mol%.

[0077] The above-mentioned ethylene and α-olefin contents can be obtained by utilizing... 13 The result is determined by C-NMR measurements.

[0078] Examples of non-conjugated polyenes include, for example, chain-like non-conjugated dienes, cyclic non-conjugated dienes, and trienes. One or more of these non-conjugated polyenes may be used.

[0079] Examples of chain-like non-conjugated dienes include, for example, 1,4-hexadiene, 1,5-hexadiene, 1,6-hexadiene, 3-methyl-1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 4,5-dimethyl-1,4-hexadiene, 7-methyl-1,6-octadiene, 3,7-dimethyl-1,6-octadiene, 5,7-dimethyl-1,7-octadiene, 8-methyl-4-ethylidene-1,7-nonadiene, and 4-ethylidene-1,7-undecadiene.

[0080] Examples of cyclic non-conjugated dienes include tetrahydroindene, methyltetrahydroindene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-propenyl-2-norbornene, 5-isopropylidene-2-norbornene, 5-vinylidene-2-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene, 5-vinyl-2-norbornene, 5-isopropenyl-2-norbornene, 5-isobutenyl-2-norbornene, 5-cyclohexylidene-2-norbornene, cyclopentadiene, dicyclopentadiene, cyclooctadiene, and norbornene.

[0081] Examples of trienes include, for instance, 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2,2-norbornediene, 4-ethylidene-8-methyl-1,7-nonadiene, 6,10-dimethyl-1,5,9-undecanetriene, 5,9-dimethyl-1,4,8-decanetriene, 6,9-dimethyl-1,5,8-decanetriene, 6,8,9-trimethyl-1,5,8-decanetriene, 6-ethyl-10-methyl-1,5,9-undecanetriene, and 4-ethylidene-1,6 -Octadiene, 7-methyl-4-ethylidene-1,6-octadiene, 7-methyl-4-ethylidene-1,6-nonadiene, 7-ethyl-4-ethylidene-1,6-nonadiene, 6,7-dimethyl-4-ethylidene-1,6-octadiene, 6,7-dimethyl-4-ethylidene-1,6-nonadiene, 4-ethylidene-1,6-decadiene, 7-methyl-4-ethylidene-1,6-decadiene, 7-methyl-6-propyl-4-ethylidene-1,6-octadiene, 4-ethylidene-1,7-nonadiene, 4-ethylidene-1,7-undecadiene.

[0082] Among them, the non-conjugated polyenes are preferably 1,4-hexadiene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, cyclopentadiene, dicyclopentadiene, 4-ethylidene-8-methyl-1,7-nonadiene, and more preferably 5-ethylidene-2-norbornene or 5-vinyl-2-norbornene.

[0083] The content of the non-conjugated polyene constituent units in the ethylene-α-olefin-nonconjugated polyene copolymer (A) is such that the iodine value of the ethylene-α-olefin-nonconjugated polyene copolymer (A) is preferably 1 to 50, more preferably 5 to 40, and particularly preferably 10 to 30. If the iodine value of the ethylene-α-olefin-nonconjugated polyene copolymer (A) is within the above range, then when the ethylene-α-olefin-nonconjugated polyene copolymer (A) (partially) is crosslinked, a uniformly crosslinked thermoplastic elastomer composition can be easily obtained.

[0084] In addition, the content of constituent units from non-conjugated polyenes is typically 2 to 20% by mass relative to 100% by mass of all constituent units constituting the ethylene-α-olefin-nonconjugated polyene copolymer (A).

[0085] As for the ethylene-α-olefin-nonconjugated polyene copolymer (A), considering the ease of obtaining a homogeneous mixture with components (B) to (E) contained in this composition, it is preferable to use the Mooney viscosity [ML] measured according to the method of ASTM D1646-19a. 1+4 [(125℃)] Preferably, the composition is 10 to 250, more preferably 30 to 150.

[0086] When the ethylene-α-olefin-nonconjugated polyene copolymer (A) itself is not within the Mooney viscosity range described above, a substance obtained by oiling using conventionally known methods (e.g., using oiling agents such as softeners described below) can be used as needed. As an oiling agent, a petroleum-based softener such as paraffin-based processing oil is preferred. The amount of oiling agent used during this oiling process is preferably an amount in which the Mooney viscosity of the oiled material is within the aforementioned range, for example, 0 to 150 parts by mass relative to 100 parts by mass of the ethylene-α-olefin-nonconjugated polyene copolymer (A).

[0087] The intrinsic viscosity [η] of the ethylene-α-olefin-nonconjugated polyene copolymer (A), as measured in naphthalene solvent at 135°C, is preferably 1 to 10 dl / g, more preferably 1.5 to 8 dl / g.

[0088] The ethylene-α-olefin-non-conjugated polyene copolymer (A) in this composition may exist in any crosslinked state, such as uncrosslinked, partially crosslinked, or fully crosslinked. When this composition contains at least a portion of the crosslinked ethylene-α-olefin-non-conjugated polyene copolymer (A), there is no particular limitation on the timing of its crosslinking. For example, at least a portion (dynamically) crosslinking of the ethylene-α-olefin-non-conjugated polyene copolymer (A) may be performed before mixing with the soft propylene copolymer (B), crystalline polyolefin (C), softener (D), and crosslinking agent (E) constituting this composition. Alternatively, at least a portion (dynamically) crosslinking of the ethylene-α-olefin-non-conjugated polyene copolymer (A) may be performed after mixing with other components constituting this composition or simultaneously with mixing.

[0089] In this composition, at least a portion of the ethylene-α-olefin-nonconjugated polyene copolymer (A) is preferably crosslinked. If the ethylene-α-olefin-nonconjugated polyene copolymer (A) is crosslinked, a composition and its molded articles with excellent mechanical properties, heat resistance, and molding appearance can be obtained.

[0090] It should be noted that as the degree of crosslinking of the ethylene-α-olefin-nonconjugated polyene copolymer (A) increases, there is a tendency for the compression set of the molded body made from this composition to decrease. Therefore, the degree of crosslinking of the ethylene-α-olefin-nonconjugated polyene copolymer (A) can be inferred from the compression set, oil swelling rate, and effective network density of the molded body made from this composition.

[0091] Considering the ease of obtaining molded articles with the practically required hardness, the content of the ethylene-α-olefin-nonconjugated polyene copolymer (A) in this composition is not particularly limited as long as it falls within the range satisfying the aforementioned molar ratios of the components constituting the composition. Generally, the upper limit is 80% by mass or less, preferably 55% by mass or less, more preferably 45% by mass or less, and even more preferably 25% by mass or less. Furthermore, the lower limit is generally 1% by mass or more, preferably 4% by mass or more.

[0092] Ethylene-α-olefin-nonconjugated polyene copolymer (A) can be synthesized by conventionally known methods or by using commercially available products.

[0093] <Soft propylene copolymer (B)>

[0094] The melting point (Tm) of the soft propylene copolymer (B) of the present invention B The temperature should be below 115°C, preferably below 113°C, more preferably below 110°C, and even more preferably below 108°C. If the melting point (Tm) of the soft propylene copolymer (B) is not observable or is below 115°C, it is preferable that the temperature is not observable or is below 113°C, more preferably below 110°C, and even more preferably below 108°C. B If the composition falls within the above-mentioned range, a composition and molded article with excellent mechanical properties and heat resistance can be obtained. The soft propylene copolymer (B) contained in this composition may be one type or two or more types.

[0095] The melting point of the soft propylene copolymer (B) can be determined specifically by the method described in the examples below.

[0096] The soft propylene copolymer (B) is a propylene polymer selected from propylene homopolymer, propylene-ethylene block copolymer, propylene-butene block copolymer, propylene-α-olefin block copolymer, propylene-ethylene random copolymer, propylene-α-olefin random copolymer, propylene-α-olefin graft copolymer, propylene-α-olefin-ethylene random copolymer, etc.

[0097] Specifically, the α-olefin described in the above-mentioned item <Ethylene-α-olefin-nonconjugated polyene copolymer (A)> is an example of the α-olefin, preferably ethylene or 1-butene, more preferably 1-butene.

[0098] These α-olefins can be one type or two or more types.

[0099] The soft propylene copolymer (B) also satisfies all of the following requirements (b-1) to (b-2).

[0100] (b-1) contains 90–50 mol% of constituent units from propylene, 0–30 mol% of constituent units from 1-butene, and 5–30 mol% of constituent units from ethylene.

[0101] (b-2) The molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is in the range of 1.0 to 3.5.

[0102] Furthermore, the soft propylene copolymer (B) of the present invention preferably satisfies one or more of the following requirements (b-3) to (b-5), and more preferably satisfies all of the requirements (b-3) to (b-5).

[0103] (b-3) The intrinsic viscosity [η] measured at 135 °C in naphthalene solvent is in the range of 0.01 to 10 dl / g.

[0104] (b-4) The regularity (mm fraction) of the three-unit assembly is above 85%.

[0105] (b-5) Heat of fusion (ΔH) is not observed or is below 50 J / g.

[0106] The following is an explanation of each of these requirements.

[0107] (b-1) Content of Constituent Units

[0108] In the soft propylene copolymer (B), considering the ease of obtaining molded articles with high transparency and good molding appearance, when the constituent units constituting the soft propylene copolymer (B) are set to 100 mol%, the content of the constituent units from propylene (hereinafter also referred to as "propylene content") is preferably 90 to 50 mol%, more preferably 85 to 55 mol%, and even more preferably 80 to 65 mol%. The content of the constituent units from 1-butene (hereinafter also referred to as "1-butene content") is preferably 0 to 30 mol%, more preferably 1 to 25 mol%, and even more preferably 1 to 20 mol%. The content of the constituent units from ethylene (hereinafter also referred to as "ethylene content") is preferably 5 to 30 mol%, more preferably 5 to 25 mol%, and even more preferably 5 to 23 mol%.

[0109] The propylene content, 1-butene content, and ethylene content mentioned above can be obtained by utilizing... 13 The determination is made by C-NMR measurements.

[0110] (b-2) Molecular weight distribution (Mw / Mn)

[0111] The molecular weight distribution (Mw / Mn) of the soft propylene copolymer (B) is preferably in the range of 1.0 to 3.5, more preferably in the range of 1.5 to 3.0, and even more preferably in the range of 1.7 to 2.8. By setting the molecular weight distribution (Mw / Mn) within the above range, the moldability of this composition becomes good.

[0112] It should be noted that in this embodiment, the molecular weight distribution (Mw / Mn) is calculated based on the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of polystyrene obtained by gel permeation chromatography (GPC).

[0113] (b-3) Intrinsic Viscosity [η]

[0114] The intrinsic viscosity [η] of the soft propylene copolymer (B), measured at 135°C in naphthalene solvent, is preferably 0.01 to 10 dl / g, more preferably 0.05 to 5.0 dl / g, and even more preferably 1.0 to 4.5 dl / g. By setting the intrinsic viscosity [η] within the above range, a thermoplastic elastomer with excellent weather resistance, ozone resistance, heat aging resistance, and low-temperature properties can be obtained.

[0115] (b-4) Regularity of Three-Unit Assembly (mm fraction)

[0116] The stereoregularity of the soft propylene copolymer (B) can be evaluated by the stereoregularity of the three-unit group (mm fraction), preferably 85% or more, more preferably 88-98%, and even more preferably 90-95%.

[0117] Here, the so-called "mm fraction" is defined as the proportion of methyl groups with the same branching direction when the polymer chain consists of three head-to-tail connected propylene unit chains represented by a serrated surface structure. It can be expressed as: 13 The C-NMR spectrum can be used to determine the mm fraction of the soft propylene copolymer (B) used in this invention. Specifically, the mm fraction can be determined by the method described on page 21, line 7 to page 26, line 6 of International Publication No. 2004 / 087775.

[0118] From the viewpoint of transparency, the soft propylene copolymer (B) used in this invention preferably has a crystallinity of no more than 30% as measured by DSC (differential scanning calorimetry) or X-ray, more preferably 25% or less, more preferably 20% or less, and even more preferably 10% or less.

[0119] (b-5) Heat of fusion (ΔH)

[0120] The heat of fusion (ΔH) of the soft propylene copolymer (B) is preferably unobservable or below 50 J / g. More preferably, it is unobservable or below 45 J / g, and even more preferably, it is unobservable or below 40 J / g. Because the soft propylene copolymer (B) of the present invention satisfies the above range, it tends to have low crystallinity, and the thermoplastic elastomer compositions containing it exhibit excellent transparency.

[0121] There are no particular limitations on the method for manufacturing the soft propylene copolymer (B) of the present invention. It can be manufactured in the presence of a known catalyst capable of stereoregular polymerization of olefins in isotactic or syndiotactic structures, such as a catalyst with solid titanium and organometallic compounds as main components, or a metallocene catalyst using a metallocene compound as one component of the catalyst. Preferably, it is manufactured by copolymerizing propylene, 1-butene, and ethylene in the presence of a metallocene catalyst. As a metallocene catalyst, for example, the catalysts described in Examples e1 to e5 of International Publication No. 2004 / 087775, the catalyst described in Japanese Patent Application Publication No. 2007-186664, etc., are preferred.

[0122] In this composition, relative to 100 parts by weight of the ethylene-α-olefin-nonconjugated polyene copolymer (A), it comprises 10 to 5,000 parts by weight of the soft propylene copolymer (B), preferably 20 to 5,000 parts by weight, more preferably 20 to 4,000 parts by weight, further preferably 25 to 3,000 parts by weight, even more preferably 27 to 2,500 parts by weight, and particularly preferably 30 to 2,500 parts by weight.

[0123] This composition forms an island structure through a phase composed of an ethylene-α-olefin-nonconjugated polyene copolymer (A) and a phase composed of a crystalline polyolefin (C). Since this composition contains a soft propylene copolymer (B) within the aforementioned range, the soft propylene copolymer (B) is compatible with the crystalline polyolefin (C) phase, thereby reducing the refractive index of the crystalline polyolefin (C) phase. Therefore, it is believed that the refractive index difference between the ethylene-α-olefin-nonconjugated polyene copolymer (A) phase and the crystalline polyolefin (C) phase decreases, thus improving transparency.

[0124] <Crystall polyolefin (C)>

[0125] The melting point (Tm) of the crystalline polyolefin (C) of the present invention C The temperature is 115°C or higher. Preferably, it is 115–175°C, more preferably 118–172°C, and even more preferably 120–170°C. If the melting point (Tm) of the crystalline polyolefin (C) is... c If the composition and molded body are within the above range, then compositions and molded bodies with excellent mechanical properties and heat resistance can be obtained.

[0126] The melting point of crystalline polyolefin (C) can be determined specifically by the method described in the examples below.

[0127] The heat of fusion (ΔH) of the crystalline polyolefin (C) of the present invention is preferably 50 J / g or more. More preferably, it is 60 J / g or more, and even more preferably, it is 70 J / g or more. Because the crystalline polyolefin (C) of the present invention satisfies the above range, it tends to have high crystallinity, and the thermoplastic elastomer composition containing it has excellent mechanical properties, heat resistance, and other physical properties.

[0128] As for the method of manufacturing crystalline polyolefin (C) used in this invention, there are no particular limitations as long as a crystalline polymer can be obtained. It is preferred to manufacture it by polymerizing one or more monoolefins through polymerization methods such as gas phase polymerization, liquid phase polymerization, slurry polymerization, bulk polymerization, etc.

[0129] Crystalline polyolefins (C) can be either homopolymers or copolymers. Homopolymers can have either isotactic or syndiotactic structures.

[0130] The aforementioned homopolymers are typically ethylene homopolymers, propylene homopolymers, or 1-butene homopolymers, preferably ethylene homopolymers or propylene homopolymers, and more preferably propylene homopolymers.

[0131] There are no restrictions on the copolymers described above, as long as two or more monoolefins have been polymerized. The copolymer structure can be either random or block.

[0132] Suitable raw material olefins include, specifically, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 2-methyl-1-propene, 3-methyl-1-pentene, 4-methyl-1-pentene, and 5-methyl-1-hexene, which are α-olefins with 2 to 20 carbon atoms. The preferred number of carbon atoms is 2 to 12, more preferably 2 to 6.

[0133] These α-olefins can be used alone or in combination of two or more.

[0134] Examples of copolymers include propylene-ethylene random copolymers, propylene-ethylene block copolymers, ethylene-1-butene copolymers, ethylene-1-hexene copolymers, and ethylene-4-methyl-1-pentene copolymers.

[0135] In addition, representative resins of crystalline polyolefins (C) are also commercially available. Examples of commercially available crystalline polyolefin (C) resins include, for example, Evolue (manufactured by Prime Polymer Co., Ltd.), Prime Polypro (manufactured by Prime Polymer Co., Ltd.), and Novatec. TM Crystalline polyolefins manufactured and sold under trade names such as (manufactured by Polypro Co., Ltd. of Japan) and Sun Aromar [registered trademark] (manufactured by Sun Aromar Co., Ltd.).

[0136] The crystalline polyolefin (C) used in this invention has the effect of improving the flowability and heat resistance of the composition.

[0137] The melt flow rate (MFR: ASTM D 1238-65T, at 230°C and 2.16 kg load) of crystalline polyolefin (C) is typically in the range of 0.01 to 100 g / 10 min, preferably in the range of 0.05 to 80 g / 10 min, more preferably in the range of 0.5 to 50 g / 10 min, and even more preferably in the range of 0.5 to 30 g / 10 min.

[0138] In this composition, relative to 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A), it comprises 10 to 500 parts by weight of crystalline polyolefin (C), preferably 30 to 450 parts by weight, and more preferably 50 to 400 parts by weight.

[0139] <Softener (D)>

[0140] In this composition, a softener is preferably used for purposes such as adjusting flowability and hardness.

[0141] Specific examples of plasticizers include: petroleum-based plasticizers such as processing oils, lubricating oils, paraffin wax, liquid paraffin wax, polyethylene wax, polypropylene wax, petroleum tar, and petroleum jelly; coal tar-based plasticizers such as coal tar and coal tar pitch; fatty oil-based plasticizers such as castor oil, linseed oil, rapeseed oil, soybean oil, and coconut oil; tall oil; rubber substitutes (vulcanized oil pastes); waxes such as beeswax, carnauba wax, and lanolin; and ricinoleic acid, palmitic acid, stearic acid, barium stearate, calcium stearate, and lauric acid. Zinc and other fatty acids or fatty acid salts; naphthenic acids; pine oil, rosin or their derivatives; synthetic polymer softeners such as terpene resins, petroleum resins, coumarin indole resins, and atactic polypropylene; ester softeners such as dioctyl phthalate, dioctyl adipate, and dioctyl sebacate; microcrystalline waxes, liquid polybutadiene, modified liquid polybutadiene, liquid polyisoprene, terminal-modified polyisoprene, hydrogenated terminal-modified polyisoprene, liquid polysulfide rubber (Thiokol), and hydrocarbon-based synthetic lubricants.

[0142] Among them, petroleum-based softeners are preferred, and processed oils are particularly preferred.

[0143] As described above, the softener can be used, for example, by premixing (oil-extruded) with ethylene-α-olefin-nonconjugated polyene copolymer (A), or by using it during the preparation of this composition, or by adding it later when the components in this composition are subjected to dynamic heat treatment.

[0144] In this composition, relative to 100 parts by weight of the ethylene-α-olefin-nonconjugated polyene copolymer (A), it contains 0 to 200 parts by weight of a softener (D), preferably 1 to 200 parts by weight, more preferably 20 to 200 parts by weight, further preferably 40 to 180 parts by weight, and particularly preferably 50 to 150 parts by weight. Additionally, relative to 100 parts by weight of the ethylene-α-olefin-nonconjugated polyene copolymer (A), it is also preferred that this composition contains 0 to 70 parts by weight or 0 to 70.0 parts by weight of the softener (D). Further, relative to 100 parts by weight of the ethylene-α-olefin-nonconjugated polyene copolymer (A), this composition more preferably contains 1 to 70 parts by weight or 1 to 70.0 parts by weight of the softener (D), further preferably 20 to 70 parts by weight or 20 to 70.0 parts by weight, and particularly preferably 40 to 70 parts by weight or 40 to 70.0 parts by weight.

[0145] If the content of the softener is within the above range, there is a tendency to easily obtain the composition with flowability suitable for molding, and further, there is a tendency to easily obtain molded articles with excellent mechanical properties, heat resistance, and heat aging resistance.

[0146] <Crosslinking agent (E)>

[0147] When it is desired to partially or completely crosslink the ethylene-α-olefin-nonconjugated polyene copolymer (A) in this composition, especially when dynamically crosslinking the uncrosslinked composition containing each component, a crosslinking agent (E) is preferably used to prepare a composition in which at least a portion of the components are crosslinked.

[0148] There are no particular limitations on the crosslinking agent (E), and conventionally known crosslinking agents can be used. Specific examples include organic peroxides, sulfur, sulfur compounds, and phenolic crosslinking agents.

[0149] Among them, organic peroxides are preferred from the viewpoints of the resulting composition, the transparency of its molded articles, high designability, heat resistance, and excellent mechanical properties.

[0150] Examples of organic peroxides include, for example, dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxide)hexane, 2,5-dimethyl-2,5-di(tert-butylperoxide)hexyn-3, 1,3-bis(tert-butylperoxide isopropyl)benzene, 1,1-bis(tert-butylperoxide)-3,3,5-trimethylcyclohexane, 4,4-bis(tert-butylperoxide)valerate n-butyl ester, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl perbenzoate, tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, and tert-butyl peroxide.

[0151] Among them, considering odor and coking stability, the preferred choices are 2,5-dimethyl-2,5-di(tert-butylperoxide)hexane, 2,5-dimethyl-2,5-di(tert-butylperoxide)hexyn-3, 1,3-bis(tert-butylperoxide isopropyl)benzene, 1,1-bis(tert-butylperoxide)-3,3,5-trimethylcyclohexane, and 4,4-bis(tert-butylperoxide)valerate n-butyl ester.

[0152] When the composition contains a crosslinking agent (E), considering the ease with which a molded body with excellent hardness can be obtained, the content of the crosslinking agent (E) in the composition is preferably 0.01 to 10 parts by weight relative to 100 parts by weight of the ethylene-α-olefin-nonconjugated polyene copolymer (A), more preferably 0.1 to 8.0 parts by weight, further preferably 0.1 to 5.0 parts by weight, and even more preferably 0.1 to 3.0 parts by weight.

[0153] <Other Ingredients>

[0154] Crosslinking aids

[0155] When using the crosslinking agent (E) described above, from the viewpoint of improving the efficiency of the crosslinking reaction, it is preferable to use a crosslinking aid.

[0156] There are no particular restrictions on crosslinking aids; any previously known crosslinking aids can be used, as long as they are appropriately selected according to the type of crosslinking agent (E).

[0157] When using organic peroxides as crosslinking agents (E), examples of crosslinking aids include, for example, sulfur, p-quinone dioxime, p,p'-dibenzoylquinone dioxime, N-methyl-N,4-dinitrosoaniline, nitrobenzene, diphenylguanidine, trimethylolpropane-N,N'-m-phenylene dimaleimide, divinylbenzene, triallyl cyanurate, vinyl butyrate, vinyl stearate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, allyl methacrylate, and other vinyl or methacrylate monomers.

[0158] Among them, divinylbenzene has good compatibility with the components constituting this composition and has a solubilizing effect on organic peroxides, thus also acting as a dispersing aid for organic peroxides. As a result, it is easy to undergo homogeneous crosslinking during heat treatment, and is therefore preferred. Therefore, by using divinylbenzene as a crosslinking aid, there is a tendency to easily obtain a composition in which flowability and physical properties are balanced.

[0159] When the composition contains a crosslinking aid, the content of the crosslinking aid in the composition is preferably 0.01 to 10.0 parts by weight, more preferably 0.1 to 8.0 parts by weight, further preferably 0.1 to 5.0 parts by weight, and particularly preferably 0.1 to 3.0 parts by weight, relative to 100 parts by weight of the ethylene-α-olefin-nonconjugated polyene copolymer (A).

[0160] Other polymers or additives

[0161] This composition may, as needed and without prejudice to the purpose of the invention, contain other polymers or additives in addition to components (A) to (E).

[0162] Other examples of such polymers include styrene-based thermoplastic elastomers, propylene-α-olefin random copolymers, butyl rubber, polyisobutylene rubber, nitrile rubber (NBR), natural rubber (NR), and silicone rubber.

[0163] Regarding the amount of other polymers added, it is typically 0.1 to 50 parts by weight, preferably 5 to 40 parts by weight, relative to 100 parts by weight of the ethylene-α-olefin-nonconjugated polyene copolymer (A) described above. One or more other polymers or additives may be used.

[0164] Specifically, examples of the aforementioned styrene-based thermoplastic elastomers include styrene-isoprene block copolymers, styrene-isoprene block copolymer hydrides (SEP), styrene-isoprene-styrene block copolymer hydrides (SEPS; polystyrene-polyethylene / propylene-polystyrene block copolymers), styrene-butadiene copolymers (e.g., styrene-butadiene block copolymers), and styrene-butadiene block copolymer hydrides (SEBS; polystyrene-polyethylene / butene-polystyrene block copolymers).

[0165] Other additives include crosslinking aids, antistatic agents, anti-aging agents, flame retardants, slip agents, nucleating agents, fillers, antioxidants, weather stabilizers, and colorants.

[0166] When using these other additives, their total amount relative to 100 parts by mass of the above-mentioned components (A) to (C) is generally 0.01 to 20 parts by mass, preferably 0.1 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass. Furthermore, for the filler, relative to 100 parts by mass of the above-mentioned component (A), it is generally 1 to 50 parts by mass, preferably 1 to 45 parts by mass, and more preferably 1 to 40 parts by mass.

[0167] As nucleating agents mentioned above, non-melting and melting crystallizing nucleating agents can be cited, and they can be used alone or in combination of two or more.

[0168] Examples of non-melting crystallizing nucleating agents include inorganic substances such as talc, mica, silica, and aluminum, brominated diphenyl ether, aluminum hydroxydi-p-tert-butylbenzoate (TBBA), organophosphates, rosin-based crystallizing nucleating agents, substituted triethylene glycol terephthalate esters, and polyester and nylon fibers. Particularly preferred are aluminum hydroxydi-p-tert-butylbenzoate, sodium methylene bis(2,4-di-tert-butylphenyl) phosphate, sodium 2,2'-methylene bis(4,6-di-tert-butylphenyl) phosphate, and rosin-based crystallizing nucleating agents.

[0169] Examples of sorbitol compounds that can be used as melting-type crystallizing nucleating agents include dibenzylidene sorbitol (DBS), substituted DBS, and lower alkyl dibenzylidene sorbitol (PDTS).

[0170] Examples of such lubricants include fatty acid amides, silicone oils, glycerin, waxes, and paraffin-based oils.

[0171] As the aforementioned filler, conventionally known fillers can be cited. Specifically, one or more fillers selected from carbon black, calcium carbonate, calcium silicate, clay, kaolin, talc, silica, diatomaceous earth, mica powder, asbestos, alumina, barium sulfate, aluminum sulfate, calcium sulfate, basic magnesium carbonate, molybdenum disulfide, graphite, glass fiber, glass beads, white sand beads, basic magnesium sulfate whiskers, calcium titanate whiskers, aluminum borate whiskers, etc.

[0172] <Preparation method and physical properties of this composition>

[0173] This composition can be manufactured by mixing and compounding ethylene-α-olefin-nonconjugated polyene copolymer (A), soft propylene copolymer (B), crystalline polyolefin (C), softener (D), crosslinking agent (E), and other additives as needed.

[0174] The composition can be manufactured using common methods employed in the manufacture of resin and elastomer compositions, such as Bamberley internal mixers, kneaders, single-screw extruders, and twin-screw extruders. Among these, a twin-screw extruder is preferred, especially from the viewpoint of effectively achieving dynamic crosslinking. A twin-screw extruder not only enables the uniform and fine dispersion of components (A) to (E), but also promotes the crosslinking reaction by adding other components. As a result, the composition can be manufactured continuously, and is therefore preferred.

[0175] Furthermore, the composition in which at least a portion of the ethylene-α-olefin-nonconjugated polyene copolymer (A) is crosslinked is preferably manufactured by dynamically crosslinking (dynamic heat treatment) an uncrosslinked composition formed by combining the ethylene-α-olefin-nonconjugated polyene copolymer (A), the soft propylene copolymer (B), the crystalline polyolefin (C), the softener (D), the crosslinking agent (E), and other additives as needed. Examples of such dynamic crosslinking include mixing and kneading components (A) to (E), and other polymers or additives as needed, using a mixing and kneading apparatus while heating, preferably while applying shear force. It should be noted that, when performing dynamic crosslinking, at least a crosslinking aid is preferably used as one of the other additives.

[0176] In addition, the soft propylene copolymer (B) in this composition can be added before or after dynamic crosslinking, or it can be added separately before and after dynamic crosslinking.

[0177] By performing dynamic crosslinking, it is possible to obtain a composition containing at least a portion of the crosslinked component of the ethylene-α-olefin-nonconjugated polyene copolymer (A). Here, "at least a portion crosslinked" means that the gel content is in the range of 5 to 98% by mass, preferably 10 to 95% by mass.

[0178] Dynamic crosslinking is preferably carried out in a non-open device, and even more preferably in an inactive gas atmosphere such as nitrogen or carbon dioxide.

[0179] The heating temperature in dynamic crosslinking is usually 125-280℃, preferably 145-240℃, and the mixing and kneading time is usually 1-30 minutes, preferably 3-20 minutes.

[0180] Furthermore, examples of shear forces applied during the aforementioned mixing and kneading processes include shear rates reaching, for example, 10 to 100,000 seconds. -1 Preferably, it is 100 to 50,000 seconds. -1 More preferably, 1,000 to 10,000 seconds. -1 Further preferably 2,000 to 7,000 seconds -1 Shear force.

[0181] As a preferred method for manufacturing this composition, the following methods can be cited as examples.

[0182] A method for manufacturing a thermoplastic elastomer composition, comprising a first step and a second step.

[0183] In the first step described above, composition (i) is obtained by dynamically crosslinking the following components:

[0184] 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A)

[0185] Melting point (Tm) cannot be observed B ) or melting point (Tm) B ) Soft propylene copolymer (B) at temperatures below 115°C: 0-5,000 parts by weight, preferably 10 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, 27 parts by weight or more, 30 parts by weight or more, less than 4,000 parts by weight, less than 3,000 parts by weight, less than 2,500 parts by weight.

[0186] Melting point (Tm) C ) is 10-500 parts by weight of crystalline polyolefin (C) with a temperature above 115℃, 0-70 parts by weight of softener (D), and

[0187] Crosslinking agent (E) 0.01-10 parts by weight,

[0188] In the second process mentioned above,

[0189] Add 0 to 5,000 parts by weight of a soft propylene copolymer (B), preferably 10 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, 27 parts by weight or more, 30 parts by weight or more, 4,000 parts by weight or less, 3,000 parts by weight or less, or 2,500 parts by weight or less to the above composition (i).

[0190] The total amount of the soft propylene copolymer (B) added in the first and second steps described above is 20 to 5,000 parts by weight.

[0191] The aforementioned soft propylene copolymer (B) also satisfies all of the following requirements (b-1) to (b-2):

[0192] (b-1) contains 90–50 mol% of constituent units from propylene, 0–30 mol% of constituent units from 1-butene, and 5–30 mol% of constituent units from ethylene.

[0193] (b-2) The molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is in the range of 1.0 to 3.5.

[0194] The first step described above is a step in which components (A) to (E) are sequentially or simultaneously introduced into an apparatus capable of melting and mixing resin components, preferably into a twin-screw extruder, and dynamically crosslinked according to the conditions described above to obtain composition (i).

[0195] The second step described above is the step of adding a soft propylene copolymer (B) to the composition (i) obtained in the first step.

[0196] In the manufacturing method of this composition, the second step can be carried out after the first step, or the obtained composition (i) can be granulated after the first step and then carried out in the second step.

[0197] In the manufacturing method of the present invention, the soft propylene copolymer (B) may be added only in the first step or only in the second step. Alternatively, a portion may be added in the first step, and the remainder added in the second step. In the manufacturing method of this composition having a first step and a second step, it is preferable to add the soft propylene copolymer (B) only in the second step, that is, the amount of the soft propylene copolymer (B) added in the first step is 0 parts by mass. In addition, in the manufacturing method of the present invention, a portion or all of the softening agent constituting the composition may be added in the second step. It should be noted that when the composition is manufactured by adding the soft propylene copolymer (B) only in the first step, it is also preferable to manufacture the composition only through the first step, that is, without the second step.

[0198] In addition, if the composition contains other components besides components (A) to (E), the other components may be added in the first step or in the second step. If a crosslinking aid is used, the crosslinking aid is preferably added in the first step.

[0199] From the perspective of making the composition with excellent formability, the melt flow rate of this composition (measured according to JIS K7210 method, at 230°C and 10kg load) is preferably 1g / 10min or more and less than 100g / 10min, more preferably 1g / 10min or more and less than 80g / 10min.

[0200] The Shore A hardness (instantaneous value) of this composition (measured according to JIS K 6253) is preferably 40 to 100, more preferably 50 to 95, and even more preferably 55 to 90.

[0201] If the Shore A hardness (instantaneous value) is within the above range, it is possible to obtain compositions and molded articles with excellent design features such as tactile feel and high-end appearance, as well as the scratch resistance required for practical use, which can be suitable for use in automotive interior trim materials and other components.

[0202] Specifically, the Shore A hardness (instantaneous value) described above can be determined by the method described in the examples below.

[0203] This composition exhibits excellent formability, making it suitable for applications requiring design features, such as texture molding. In addition, it also has excellent transparency.

[0204] [Molded body]

[0205] The molded article of the present invention is not particularly limited as long as it contains the present composition, and can be obtained by molding using any known molding method according to its intended use. Examples of molding methods include compression molding, injection molding, extrusion molding, calendering, blow molding, vacuum molding, and compression molding. The molded article of the present invention can be a molded article obtained solely from the present composition, or it can be a molded article obtained by combining it with other materials. Furthermore, the molded article of the present invention can be used alone or in combination with molded articles made of other materials.

[0206] The internal haze of the molded article of the present invention is preferably 80% or less, more preferably 70% or less, and even more preferably 50% or less. If the internal haze is 80% or less, the transparency of the molded article is good. Here, the internal haze of the molded article refers to the haze after removing the haze caused by the shape of the outer surface of the molded article.

[0207] Furthermore, the total light transmittance of the molded article of the present invention is preferably 83% or more, more preferably 85% or more. If the total light transmittance is 85% or more, the molded article has good transparency.

[0208] Specifically, the internal haze and total light transmittance can be determined by the methods described in the examples described later.

[0209] The molded articles of the present invention are suitable for use as automotive interior surface materials.

[0210] As a material used for automotive interior trim, suitable examples include instrument panels, door trim, armrests, or consoles.

[0211] Furthermore, the molded body of the present invention can also be used as part of the interior decoration of buildings (office buildings, hotels, shops, ordinary homes, etc.). In addition, the molded body of the present invention can be applied to various display devices, decorative panels, LCD TVs, lighting switches, bathroom displays, furniture, audio equipment, speakers, and home appliances (rice cookers, microwave ovens, washing machines, air conditioner panels, telephones, remote controls, etc.) for various purposes.

[0212] Decorative Panels

[0213] Molded bodies made from the thermoplastic elastomer composition of the present invention are suitable as surface layers for decorative panels having display devices or operating parts due to the excellent moldability and transparency of the composition. Examples of decorative panels according to the present invention include decorative panels having display devices or operating parts.

[0214] The decorative panel of the present invention comprises a molded body containing a thermoplastic elastomer composition and a display device or operating part disposed at the lower part of the molded body, wherein the thermoplastic elastomer composition comprises:

[0215] 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A)

[0216] Melting point (Tm) cannot be observed B ) or melting point (Tm) B 10-5,000 parts by weight of soft propylene copolymer (B) at temperatures below 115°C

[0217] Melting point (Tm) C The composition includes 10-500 parts by weight of crystalline polyolefin (C) with a temperature above 115°C, 0-200 parts by weight of plasticizer (D), and...

[0218] Crosslinking agent (E) 0.01 to 10 parts by weight.

[0219] The thermoplastic elastomer composition contained in the molded body constituting the decorative panel of the present invention is preferably the composition described above. Specifically, the preferred thermoplastic elastomer composition contained in the molded body constituting the decorative panel of the present invention includes:

[0220] 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A)

[0221] Melting point (Tm) cannot be observed B ) or melting point (Tm) B 20-5,000 parts by weight of soft propylene copolymer (B) at temperatures below 115°C

[0222] Melting point (Tm) C ) is 10-500 parts by weight of crystalline polyolefin (C) at temperatures above 115℃.

[0223] 0-70 parts by weight of softener (D), and

[0224] Crosslinking agent (E) 0.01-10 parts by weight,

[0225] The aforementioned soft propylene copolymer (B) further satisfies the following requirement (b-1).

[0226] (b-1) contains 90–50 mol% of constituent units from propylene, 0–30 mol% of constituent units from 1-butene, and 5–30 mol% of constituent units from ethylene.

[0227] In addition, preferably, the above-mentioned soft propylene copolymer (B) further satisfies the following requirement (b-2).

[0228] (b-2) The molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is in the range of 1.0 to 3.5.

[0229] The decorative panel of the present invention is typically configured such that a display device or operating part is provided at the lower part of a molded body containing a thermoplastic elastomer composition. That is, the molded body containing a thermoplastic elastomer composition is provided on the display device or operating part, so that the display shown by the display device or operating part can be visually identified through the molded body containing the thermoplastic elastomer composition.

[0230] In one embodiment of the decorative panel of the present invention, it can be configured such that when the light source of the display device or the operating unit emits light, the display shown by the display device or the operating unit can be visually identified through the molded body containing the thermoplastic elastomer composition; on the other hand, when the light source does not emit light (non-emitting light), only the surface of the molded body can be visually identified.

[0231] Such a decorative panel of the present invention can be suitably used in the instrument panel of automobiles, various devices with display devices or operating parts, etc., and is especially suitable for applications requiring design in automobile interiors or interiors.

[0232] Example

[0233] The present invention will now be described in detail based on embodiments, but the present invention is not limited to these embodiments. In the following embodiments and other descriptions, unless specifically mentioned otherwise, "parts" means "parts by mass".

[0234] The methods for determining the physical properties of the raw materials used in the examples and comparative examples are as follows.

[0235] [Mass fraction of constituent units]

[0236] The mass fraction (mass%) of each constituent unit in the ethylene-α-olefin-nonconjugated polyene copolymer (A-1) is determined by... 13 The values ​​were obtained from C-NMR measurements. Specifically, an ECX400P nuclear magnetic resonance spectrometer (manufactured by NEC Corporation) was used, under the following conditions: measurement temperature: 120°C; measurement solvent: o-dichlorobenzene / deuterated benzene = 4 / 1 (volume ratio); and cumulative measurements: 8000. The values ​​were obtained from the copolymer (A-1). 13 The C-NMR spectrum was calculated.

[0237] [Weight-average molecular weight (Mw), number-average molecular weight (Mn), and molecular weight distribution (Mw / Mn)]

[0238] The weight-average molecular weight (Mw), number-average molecular weight (Mn), and molecular weight distribution (Mw / Mn) of the soft propylene copolymers (B-1), (B-2), and (B-3) were determined by gel permeation chromatography (GPC) at a column temperature of 140 °C. The weight-average molecular weight (Mw) and number-average molecular weight (Mn) were determined by conversion to standard polystyrene. Mw / Mn was calculated based on the weight-average molecular weight (Mw) and number-average molecular weight (Mn).

[0239] [Melting point (Tm) and heat of fusion (ΔH)]

[0240] The melting points of the soft propylene copolymers (B-1), (B-2), and (B-3) and the crystalline polyolefins (C-1) and (C-2) were determined by differential scanning calorimetry (DSC) using the following method.

[0241] 10 mg of sample was placed in a special aluminum dish and heated from room temperature to 200 °C at a rate of 10 °C / min using an X-DSC7000 (manufactured by SII) under a nitrogen atmosphere. The temperature was held at 200 °C for 5 minutes, then cooled to -100 °C at a rate of 10 °C / min. The temperature was then held at -100 °C for 5 minutes, followed by a second heating to 200 °C at a rate of 10 °C / min. The melting point (Tm) and heat of fusion (ΔH) of the polymer were determined from the peak of the endothermic curve during the second heating.

[0242] The heat of fusion (ΔH) is calculated by taking the line connecting the point on the low-temperature side where the heat remains unchanged and the point on the high-temperature side where the heat remains unchanged as the baseline, and finding the area enclosed by the line portion containing the peak of the endothermic curve obtained by the above measurement and the baseline.

[0243] Here, when multiple peaks are detected in the endothermic curve, the temperature and peak area of ​​the peak detected at the highest temperature side are set as the melting point (Tm) and heat of fusion (ΔH), respectively. Additionally, if no peak with a heat of fusion (ΔH) greater than 1 J / g is observed within the aforementioned measurement temperature range (-100℃~200℃), it is set as if no melting point (Tm) and heat of fusion (ΔH) are observed.

[0244] [Intrinsic Viscosity]

[0245] The intrinsic viscosity [η] of the above-mentioned soft polypropylene (B-1) and (B-2) is a value obtained by measuring with naphthalene solvent at 135°C.

[0246] Specifically, approximately 20 mg of an ethylene-α-olefin-nonconjugated polyene copolymer was dissolved in 15 ml of naphthalene, and the specific viscosity η was measured in an oil bath at 135 °C. sp After diluting the naphthalene solution with 5 ml of naphthalene solvent, the specific viscosity η was measured similarly. sp Repeat this dilution operation twice more to determine η when the concentration (C) is extrapolated to 0. sp / C value is used as the intrinsic viscosity (refer to the following formula).

[0247] [η]=lim(ηsp / C)(C→0)

[0248] [raw material]

[0249] The raw materials used in the examples and comparative examples are as follows.

[0250] (1) Ethylene-α-olefin-nonconjugated polyene copolymer (A-1)

[0251] • Oil-extended ethylene-propylene-nonconjugated diene copolymer rubber (EPDM, trade name: 3072EPM; manufactured by Mitsui Chemicals Co., Ltd.)

[0252] • Ethylene content = 64% by mass, propylene content = 30.6% by mass, non-conjugated diene: 5-ethylidene-2-norbornene, non-conjugated diene content = 5.4% by mass

[0253] Mooney viscosity [ML] (1+4) 125℃]=51

[0254] The oil content (parts by mass) relative to 100 parts by mass of ethylene-α-olefin-nonconjugated polyene copolymer is 40 (PHR).

[0255] It should be noted that the values ​​for copolymer (A-1) in Table 1 represent the amount of rubber component only, excluding oil addition. For oil addition of copolymer (A-1), paraffin-based processing oil ("PW-100" manufactured by Idemitsu Kosan Co., Ltd., the softener described below) was used.

[0256] (2) Soft propylene copolymer (B)

[0257] [Synthetic Example 1] Preparation of Soft Acrylic Copolymer (B-1)

[0258] As a catalyst / co-catalyst, diphenylmethylene (3-tert-butyl-5-ethylcyclopentadienyl)(2,7-tert-fluorenyl)zirconium dichloride / methylaluminoxane (manufactured by Tosoh Seika Co., Ltd., 0.3 mmol in aluminum equivalent) prepared by the method described in Japanese Patent Application Publication No. 2007-186664 was used to polymerize ethylene, propylene and 1-butene as raw materials in a hexane solution using a continuous polymerization apparatus, thereby obtaining a random copolymer of propylene-1-butene-ethylene (PBER-1) (propylene 76 mol%, 1-butene 6 mol%, ethylene 18 mol%, unobserved melting point (ΔH less than 0.5 J / g)), Mw / Mn = 2.1, intrinsic viscosity [η] = 1.4 dl / g).

[0259] [Synthesis Example 2] Preparation of Soft Acrylic Copolymer (B-2)

[0260] As a catalyst / co-catalyst, diphenylmethylene (3-tert-butyl-5-ethylcyclopentadienyl)(2,7-tert-fluorenyl)zirconium dichloride / methylaluminoxane (manufactured by Tosoh Seika Co., Ltd., 0.3 mmol in aluminum equivalent) prepared by the method described in Japanese Patent Application Publication No. 2007-186664 was used to polymerize ethylene, propylene and 1-butene as raw materials in a hexane solution using a continuous polymerization apparatus, thereby obtaining a random copolymer of propylene-1-butene-ethylene (PBER-1) (propylene 67 mol%, 19 mol% 1-butene, 14 mol% ethylene, unobserved melting point (ΔH less than 0.5 J / g), Mw / Mn = 2.1, intrinsic viscosity [η] = 1.8 dl / g).

[0261] Soft propylene copolymer (B-3)

[0262] • Propylene-α-olefin random copolymer (trade name: Vistamaxx 6102, manufactured by ExxonMobil, ethylene content = 21.4 mol%, melting point = 105℃, ΔH = 10 J / g, Mw / Mn = 2.1, MFR (230℃, 2.16 kg load) = 3.0 g / 10 min)

[0263] (3) Crystalline polyolefins (C)

[0264] Crystalline polyolefins (C-1)

[0265] • Propylene-ethylene block copolymer (trade name: EL-Pro P740J; manufactured by SCG Chemicals, MFR (determined according to ASTM D 1238-65T method; at 230°C, 2.16 kg load) = 27 g / 10 min, melting point = 163°C, ΔH = 93 J / g)

[0266] Crystalline polyolefins (C-2)

[0267] • Propylene homopolymer (trade name: Prime Polypro J105; manufactured by Prime Polymers, MFR (determined according to ASTM D 1238-65T method; at 230°C, 2.16 kg load) = 5 g / 10 min, melting point = 167°C, ΔH = 105 J / g)

[0268] (4) Softener (D-1)

[0269] • Paraffin-based processing oil (trade name: Diana Process Oil PW-100, manufactured by Idemitsu Kosan Co., Ltd.)

[0270] It should be noted that the values ​​for softener (D-1) in Table 1 include the amount of oil added from the copolymer.

[0271] (5) Crosslinking agent (E-1)

[0272] • Organic peroxide (2,5-dimethyl-2,5-di(tert-butylperoxide)hexane), trade name: PERHEXA25B, manufactured by Nippon Oil Co., Ltd.

[0273] (6) Other ingredients

[0274] (6-1) Crosslinking aids

[0275] • Divinylbenzene (trade name: DVB-810, manufactured by Nippon Steel Chemical Materials Co., Ltd.)

[0276] [Example 1]

[0277] Relative to 100 parts by mass of copolymer (A) (140 parts by mass of oil-extended ethylene-propylene-nonconjugated diene copolymer rubber (EPDM, trade name: 3072EPM; manufactured by Mitsui Chemicals Co., Ltd.)), 2000 parts by mass of copolymer (B-1) synthesized in Synthesis Example 1, 350 parts by mass of crystalline polyolefin (C-1), 1.0 part by mass of crosslinking agent (E-1), and 1.0 part by mass of divinylbenzene as a crosslinking aid were thoroughly mixed using a Henschel mixer. Granulation was carried out using an extruder (model name: HYPERKTX-46, manufactured by Kobe Steel Co., Ltd., barrel temperature: C1=110℃, C2=120℃, C3=140℃, C4=140℃, C5=150℃, C6=160℃, C7~C8=180℃, C9~C14=230℃, die temperature: 200℃), while injecting a softener (D-1) into the barrel in an amount of 50 parts by weight containing the copolymer (A) to obtain granules of a thermoplastic elastomer composition.

[0278] [Examples 2-7]

[0279] The proportions of the raw materials used were changed as shown in Table 1. Otherwise, the granules of the thermoplastic elastomer composition were obtained in the same manner as in Example 1.

[0280] [Example 8]

[0281] The copolymer (B-1) used was changed to the copolymer (B-2) synthesized in Synthesis Example 2, and the proportions of the raw materials used were changed as shown in Table 1. Otherwise, the granules of the thermoplastic elastomer composition were obtained in the same manner as in Example 1.

[0282] [Example 9]

[0283] The copolymer (B-1) used was changed to copolymer (B-3), and the proportions of the raw materials used were changed as shown in Table 1. Otherwise, the granules of the thermoplastic elastomer composition were obtained in the same manner as in Example 1.

[0284] [Examples 10-11]

[0285] The proportions of the raw materials used were modified as shown in Table 1, and a crystalline polyolefin (C-2) was further used. Otherwise, the granules of the thermoplastic elastomer composition were obtained in the same manner as in Example 1.

[0286] [Example 12]

[0287] Relative to 100 parts by weight of copolymer (A) (140 parts by weight of oil-extended ethylene-propylene-nonconjugated diene copolymer rubber (EPDM, trade name: 3072EPM; manufactured by Mitsui Chemicals Co., Ltd.)), 350 parts by weight of crystalline polyolefin (C-1), 1.0 part by weight of crosslinking agent (E-1) and 1.0 part by weight of divinylbenzene as crosslinking aid were thoroughly mixed using a Henschel mixer. Granulation of a thermoplastic elastomer composition was carried out using an extruder (model name: HYPERKTX-46, manufactured by Kobe Steel Co., Ltd., barrel temperatures: C1=110℃, C2=120℃, C3=140℃, C4=140℃, C5=150℃, C6=160℃, C7~C8=180℃, C9~C14=230℃, die temperature: 200℃). While injecting 50 parts by weight of softener (D-1) containing the copolymer (A) into the barrel, granulation was performed to produce granules of the thermoplastic elastomer composition. The resulting thermoplastic elastomer composition and 2000 parts by weight of the copolymer (B-1) synthesized in Synthesis Example 1 were then granulated again through the above extrusion process to obtain granules of the thermoplastic elastomer composition.

[0288] [Example 13]

[0289] The proportions of the raw materials used were modified as shown in Table 1. Otherwise, the granules of the thermoplastic elastomer composition were obtained in the same manner as in Example 12.

[0290] [Comparative Examples 1-2]

[0291] Without using copolymer (B-1) and by changing the proportions of raw materials as shown in Table 1, granules of the thermoplastic elastomer composition were obtained in the same manner as in Example 1.

[0292] [Evaluation methods for thermoplastic elastomer compositions]

[0293] <Production of Pressed Discs>

[0294] The granules of the thermoplastic elastomer compositions obtained in the examples and comparative examples were pressed using a hot press molding machine (pressing temperature: 190°C, cooling temperature: 20°C, preheating time: 6 minutes, pressurization melting time: 4 minutes). As a result of the pressing process, two flat sheets of different thicknesses were produced for each composition. The resulting sheets were 12cm x 14.7cm x 2mm and 12cm x 14.7cm x 0.5mm, respectively.

[0295] <Shore A Hardness (Instantaneous Value)>

[0296] Three 2mm thick pressed sheets were stacked together to serve as test samples. The Shore A hardness (instantaneous value) was determined using a hardness tester according to the method described in JIS K 6253. The results are shown in Table 1.

[0297] <Mel flow rate (MFR)>

[0298] According to JIS K 7210, melt flow rates were determined using granules of the thermoplastic elastomer compositions obtained in the examples and comparative examples at 230°C and a 10 kg load. The results are shown in Table 1.

[0299] <Modulus, stress at tensile fracture, elongation at tensile fracture>

[0300] The 2mm thick pressed sheet was punched to produce dumbbell-shaped No. 3 test pieces. Using the prepared test pieces, tensile tests were performed according to JISK 6251 (tensile speed: 500mm / min, measurement temperature: 23℃), and the modulus at 100% elongation (M100), stress at fracture (TB), and elongation at fracture (EB) were measured. The results are shown in Table 1.

[0301] <Internal haze, total light transmittance>

[0302] Using the 0.5 mm thick pressed sheet described above, the haze value and total light transmittance were measured according to JIS K 7105. The results are shown in Table 1.

[0303] Preparation of samples for evaluating vacuum formability (texture transferability, corner transferability)

[0304] Using the above-mentioned thermoplastic elastomer composition granules, sheets with a thickness of 1.0 mm were produced using a T-die forming machine (manufactured by Toshiba Machinery Co., Ltd., with barrel temperatures of C1=160℃, C2=170℃, C3=180℃, C4=190℃, C5~C6=200℃, D1~D5=200℃, roller temperature of 60~80℃, traction speed of 1.1m / min, and rotation speed of 55rpm).

[0305] The above-mentioned sheet material was shaped in a textured mold using vacuum forming (forming temperature: 160°C, BVF-1010-PWB vacuum forming machine manufactured by Buse Vacuum Co., Ltd.), thereby producing molded samples in the shape of textured instrument panels and door trim parts. Using the shaped molded samples, the texture transfer and corner transfer properties were evaluated according to the following criteria.

[0306] <Texture transferability>

[0307] Texture transferability was evaluated visually. A maximum score of 5 points was used, and the evaluation criteria were as follows. Three people participated in the evaluation, and the average score was given.

[0308] (Evaluation Criteria)

[0309] 5 points: The texture of the molded object is transferred very clearly, and the texture transfer performance is excellent.

[0310] 4 points: The texture of the molded object is clearly transferred, and the texture transferability is excellent.

[0311] 3 points: The texture of the molded object is transferred to a recognizable degree, and the texture transfer is good.

[0312] 2 points: The texture of the molded body was not transferred, and the texture transfer was poor.

[0313] 1 point: The texture of the molded object was not transferred at all, indicating poor texture transferability.

[0314] <Corner Transfer Properties>

[0315] The transferability of the corner shape of the sheet material of the above-mentioned molded sample was evaluated visually. The scoring was set at 5 points out of 5, and the evaluation criteria were as follows. Three evaluators were involved, and the average score of the three evaluators was given.

[0316] (Evaluation Criteria)

[0317] 5 points: The corners of the molded object are transferred very clearly, and the corner transfer performance is excellent.

[0318] 4 points: The corners of the molded object are clearly transferred, and the corner transfer performance is excellent.

[0319] 3 points: The corners of the molded object are transferred to a recognizable degree, and the corner transfer performance is good.

[0320] 2 points: The corners of the molded object were not transferred and instead have rounded corners, indicating poor corner transfer. 1 point: The corners of the molded object were not transferred and instead have rounded corners, indicating poor corner transfer.

[0321] [Table 1]

[0322]

Claims

1. A thermoplastic elastomer composition comprising: 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A) Melting point Tm not observed B or melting point Tm B Soft propylene copolymer (B) at temperatures below 115°C: 210-5,000 parts by weight Melting point Tm C 30-500 parts by weight of crystalline polyolefin (C) at temperatures above 115℃ 0-70 parts by weight of softener (D), and Crosslinking agent (E) 0.01~10 parts by weight, The soft propylene copolymer (B) also satisfies all of the following requirements (b-1) to (b-2): (b-1) contains 90-50 mol% of constituent units from propylene, 0-30 mol% of constituent units from 1-butene, and 5-30 mol% of constituent units from ethylene. (b-2) The molecular weight distribution determined by gel permeation chromatography (GPC), i.e., Mw / Mn, is in the range of 1.0 to 3.

5.

2. The thermoplastic elastomer composition according to claim 1, wherein the crosslinking agent (E) is an organic peroxide.

3. The thermoplastic elastomer composition according to claim 1 or 2, wherein the melt flow rate, measured according to JIS K 7210 at 230°C and under a 10kg load, is 1 g / 10 min or more and less than 80 g / 10 min.

4. The thermoplastic elastomer composition according to claim 1 or 2, wherein, At least a portion of the ethylene-α-olefin-nonconjugated polyene copolymer (A) has been crosslinked.

5. The thermoplastic elastomer composition according to claim 1 or 2, wherein the instantaneous Shore A hardness, measured according to the JIS K 6235 method, is 40 to 100 when three sheets of 2 mm thickness are stacked together.

6. A molded article comprising the thermoplastic elastomer composition of claim 1 or 2.

7. The molded body according to claim 6, wherein the internal haze is below 80%.

8. The molded article according to claim 6 has a total light transmittance of 83% or more.

9. The molded body according to claim 6 is an automotive interior skin material.

10. The molded body according to claim 9, wherein the automotive interior skin material is an instrument panel, door trim, armrest, or console.

11. A decorative panel, characterized in that, The device comprises a molded body containing a thermoplastic elastomer composition and a display device or operating part disposed at the lower part of the molded body. The thermoplastic elastomer composition comprises: 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A) Melting point Tm not observed B or melting point Tm B Soft propylene copolymer (B) at temperatures below 115°C: 210-5,000 parts by weight Melting point Tm C 30-500 parts by weight of crystalline polyolefin (C) at temperatures above 115℃ 0-200 parts by weight of softener (D), and Crosslinking agent (E) 0.01~10 parts by weight.

12. A method for manufacturing a thermoplastic elastomer composition, the method comprising: The first step involves using 100 parts by weight of ethylene-α-olefin-nonconjugated polyene copolymer (A), whose melting point Tm cannot be observed. B or melting point Tm B Soft propylene copolymer (B) with a melting point below 115℃ (0-5,000 parts by weight) and a melting point Tm C Composition (i) is obtained by dynamically crosslinking 30-500 parts by weight of a crystalline polyolefin (C) at temperatures above 115°C, 0-70 parts by weight of a softener (D), and 0.01-10 parts by weight of a crosslinking agent (E); In the second step, 0-5,000 parts by weight of a soft propylene copolymer (B) are added to the composition (i). The total amount of the soft propylene copolymer (B) added in the first and second steps is 210 to 5,000 parts by weight. The soft propylene copolymer (B) also satisfies all of the following requirements (b-1) to (b-2): (b-1) contains 90-50 mol% of constituent units from propylene, 0-30 mol% of constituent units from 1-butene, and 5-30 mol% of constituent units from ethylene. (b-2) The molecular weight distribution determined by gel permeation chromatography (GPC), i.e., Mw / Mn, is in the range of 1.0 to 3.

5.

13. The method for manufacturing the thermoplastic elastomer composition according to claim 12, wherein the amount of the soft propylene copolymer (B) added in the first step is 0 parts by mass.

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