JP2003176385A - Thermoplastic elastomer composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyolefin-based thermoplastic elastomer composition which has excellent abrasion resistance, oil resistance, extrusion moldability, and injection moldability and is used for automotive interior members, automotive exterior members, building members and household electric appliance members. <P>SOLUTION: This thermoplastic elastomer composition is obtained by melt- kneading a composition comprising (a) 10 to 90 wt.% of an olefinic copolymer rubber, (b) 10 to 90 wt.% of an ethylenic polymer, wherein the total amount of the components (a) and (b) is 100 pts.wt., (c) 0.01 to 10 pts.wt. of an ester- based cross-linking auxiliary, and (d) 0.01 to 3.0 pts.wt. of an organic peroxide. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermoplastic elastomer composition, and more particularly to a thermoplastic elastomer composition having excellent wear resistance, oil resistance, extrusion moldability and injection moldability.

[0002]

2. Description of the Related Art In recent years, a thermoplastic polyolefin elastomer (TPO) or polystyrene based material which is a soft material having rubber elasticity and which does not require a vulcanization step and has the same processability and recycling as a thermoplastic resin. BACKGROUND ART Thermoplastic elastomers, which are thermoplastic elastomers, are widely used in fields such as automobile parts, home electric appliance parts, wire coatings, medical parts, footwear, and sundries.

Among thermoplastic elastomers, a thermoplastic polyolefin elastomer (TPO) which does not add a low molecular weight such as a plasticizer as much as possible has excellent abrasion resistance.
When a wear resistance test or a car wash test is performed using a high load or a rough probe, there is a problem that the product surface is scraped or the gloss is significantly reduced.

[0004]

SUMMARY OF THE INVENTION In view of the above problems, the present invention has an interior / exterior member for automobiles, a member for construction, a member for home appliances, which is excellent in wear resistance, oil resistance, extrusion moldability and injection moldability,
An object is to provide a polyolefin-based thermoplastic elastomer composition for medical devices.

[0005]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have blended an olefin copolymer rubber with an ethylene polymer and an ester crosslinking aid. Then, it was found that a thermoplastic elastomer having excellent wear resistance, oil resistance, extrusion moldability, and injection moldability can be obtained by the crosslinking treatment, and the present invention has been completed.

That is, the first aspect of the present invention is (a)
Olefin-based copolymer rubber: 10 to 90% by weight, (b) Ethylene-based polymer: 10 to 90% by weight, (c) Ester-based crosslinking aid based on 100 parts by weight of the total of components (a) and (b). It is a thermoplastic elastomer composition obtained by melt-kneading a composition containing an agent: 0.01 to 10 parts by weight, and (d) an organic peroxide: 0.01 to 3.0 parts by weight.

The second invention of the present invention is that (a) the Mooney viscosity (ML _{1 + 4} (1
00 ° C)) is 7 to 75, which is the thermoplastic elastomer composition according to the first invention.

The third invention of the present invention is (b) the thermoplastic elastomer composition according to the first or second invention, wherein 50% by weight or more of the ethylene polymer is a polyethylene resin.

The fourth invention of the present invention is the thermoplastic elastomer composition according to any one of the first to third inventions, wherein the (c) ester crosslinking aid is a monoacrylate.

The fifth aspect of the present invention provides the component (a)
The thermoplastic elastomer composition according to the first to fourth inventions, further comprising (e) 0.5 to 15 parts by weight of silica sol or colloidal silica based on 100 parts by weight of (b).

The sixth aspect of the present invention is to provide (f) at least two polymer blocks A mainly containing an aromatic vinyl compound and at least one polymer block B mainly containing a conjugated diene compound. A block copolymer consisting of and / or a hydrogenated block copolymer obtained by hydrogenating the same with 100 parts by weight of the components (a) and (b) in total.
The thermoplastic elastomer composition according to the first to fifth inventions, further comprising 1 to 35 parts by weight.

The seventh invention of the present invention is that the component (a)
The thermoplastic elastomer composition according to any one of the first to sixth inventions, further comprising (g) 1 to 30 parts by weight of the peroxide-decomposable olefin resin with respect to 100 parts by weight in total.

An eighth aspect of the present invention is an automobile interior / exterior member, a building member or a household appliance member, which is obtained by molding the thermoplastic elastomer composition according to any one of the first to seventh inventions. is there.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The components constituting the present invention, the production method, and the use are described in detail below.

1. Component (1) Olefin Copolymer Rubber Component (a) of Thermoplastic Elastomer Composition Olefin Copolymer Rubber Component (a) Used in the Present Invention
Examples thereof include an elastomer obtained by copolymerizing α-olefins such as ethylene, propylene, 1-butene and 1-pentene, and an olefin copolymer rubber obtained by copolymerizing these with a non-conjugated diene.

The non-conjugated dienes include dicyclopentadiene, 1,4-hexadiene, dicyclooctadiene,
Examples thereof include methylene norbornene and 5-ethylidene-2-norbornene.

Specific examples of such olefin copolymer rubbers include ethylene-propylene copolymer rubber, ethylene-propylene-non-conjugated diene copolymer rubber, ethylene-1-butene copolymer rubber, Ethylene-1
Examples include butene-non-conjugated diene copolymer rubber and ethylene-propylene-1-butene copolymer rubber.

The olefinic copolymer rubber used in the present invention has a Mooney viscosity (ML _{1 + 4} (100 ° C.)) of 7 to 7.
It is preferably 5, and more preferably 10 to 60. Particularly, when the Mooney viscosity (ML _{1 + 4} (100 ° C.)) is 10 to 30, the surface gloss of the injection molded product is 40 to 70,
The surface gloss of the extruded product is 10 to 20. When the Mooney viscosity (ML _{1 + 4} (100 ° C.)) is 30 to 40,
The surface gloss of the injection molded product is 10 to 40, and the surface gloss of the extrusion molded product is 4 to 10. Mooney viscosity (ML _{1 +4} (1
00 ° C.) is 40 to 60, the surface gloss of the injection molded product is 3 to 10 and the surface gloss of the extrusion molded product is 0 to 4. When the Mooney viscosity (ML _{1 + 4} (100 ° C.)) is less than 7,
Oil resistance and wear resistance deteriorate, and if it exceeds 75, moldability deteriorates.

The content of the component (a) is 10 to 90% by weight, preferably 30 to 70% by weight based on the total 100% by weight of the components (a) and (b). If it is less than 10% by weight, moldability is deteriorated, and if it exceeds 90% by weight, mechanical properties and scratch resistance are deteriorated.

(2) Ethylene polymer component (b) As the ethylene polymer component (b) used in the present invention,
Examples thereof include homopolymers of ethylene, α-olefins such as ethylene and propylene, 1-butene and 1-pentene, and copolymer resins obtained by copolymerizing vinyl acetate, ethyl acrylate, butyl acrylate and methyl acrylate.

Examples of the component (b) include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, ultra-low-density polyethylene, ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer. (EEA), ethylene-butyl acrylate copolymer (EBA), ethylene-methyl acrylate copolymer (EMA), and the like, which may be used alone or 2
You may mix and use 1 or more types. Among these, high density polyethylene is particularly preferable for exhibiting excellent abrasion resistance, and when two or more kinds are mixed and used, it is preferable that at least a polyethylene resin such as high density polyethylene is present. . Specifically, it is preferably 50% by weight or more, more preferably 60% by weight or more, still more preferably 70% by weight or more.

In order to impart flexibility to the elastomer composition, it is preferable to use an ethylene-vinyl acetate copolymer (EVA) or an ethylene-ethyl acrylate copolymer (EEA) together, and in the EVA and EEA used at that time. The content of VA or EA is preferably 20 to 50% by weight, more preferably 25 to 45% by weight, and further preferably 30 to 45% by weight. If the amount of VA or EA is less than 20% by weight, there is no effect of addition, and if it exceeds 50% by weight, not only the mechanical properties deteriorate, but also the formability deteriorates.

MFR of ethylene polymer used in the present invention
(190 ° C, 2.16 kg) is 0.01 to 150 g /
It is 10 minutes, preferably 0.03 to 20 g / 10 minutes, and more preferably 0.03 to 15 g / 10 minutes. 0.01
If it is less than g / 10 minutes, the moldability is deteriorated, and if it exceeds 150 g / 10 minutes, the mechanical properties are deteriorated.

The blending amount of the component (b) is 10 to 90% by weight based on 100% by weight of the components (a) and (b).
And preferably 30 to 70% by weight. If it is less than 10% by weight, the moldability is deteriorated, and if it exceeds 90% by weight, the flexibility is lost, whitening occurs in the abrasion resistance test, and the moldability is deteriorated.

(3) Ester-based cross-linking aid component (c) The ester-based cross-linking aid component (c) used in the present invention is used for the cross-linking treatment of the elastomer composition of the present invention with (d) the organic peroxide described below. , Plays a more uniform and efficient crosslinking and / or grafting reaction, and improves the wear resistance of the surface of the molded article.

Specific examples of the component (c) include monoacrylate compounds, and specific compounds include, for example, methoxydiethylene glycol methacrylate,
Methoxy polyethylene glycol 230 methacrylate (the ethylene glycol repeating unit n of the polyethylene glycol portion is 4 on average), methoxy polyethylene glycol 400 methacrylate (the ethylene glycol repeating unit n of the polyethylene glycol portion is 9 on average), methoxy polyethylene glycol 1000 methacrylate ( The ethylene glycol repeating unit n of the polyethylene glycol portion is 23 on average), β-methacryloyloxyethyl hydrogen phthalate, β-methacryloyloxyethyl hydrogen succinate,
3-chloro-2-hydroxypropyl methacrylate, stearyl methacrylate, phenoxyethyl acrylate, phenoxypolyethylene glycol acrylate, methoxypolyethylene glycol 400 acrylate (the ethylene glycol repeating unit n of the polyethylene glycol part is 9 on average), β-acryloyloxyethyl Examples include hydrogen succinate and lauryl acrylate. Of these monoacrylates, β-methacryloyloxyethyl hydrogen phthalate and β-methacryloyloxyethyl hydrogen succinate are particularly preferable. These may be used alone or in combination of two or more.

The blending amount of the component (c) is preferably 0.01 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the components (a) and (b) in total. . If it is less than 0.01 parts by weight, the effect of addition is not obtained, and if it exceeds 10 parts by weight, bleeding becomes remarkable, the appearance of the molded product is deteriorated and the wear resistance is lowered.

(4) Organic Peroxide Component (d) The organic peroxide component (d) used in the present invention generates radicals and causes the radicals to react in a chain reaction to form the component (a) and the component (a). It functions to crosslink b). Also,
At the same time, if necessary, the component (g) to be blended is decomposed to control the fluidity of the composition at the time of melt-kneading, and to disperse the rubber component well. Examples of the component (d) include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert.
-Butylperoxy) hexane, 2,5-dimethyl-
2,5-di- (tert-butylperoxy) hexyne-3,1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5 -Trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, tert. -Butyl peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, tert-butyl cumyl peroxide, etc. can be mentioned. Of these, 2,5-dimethyl-2,5-from the viewpoint of odor, coloring and scorch safety.
Di- (tert-butylperoxy) hexane, 2,5
-Dimethyl-2,5-di- (tert-butylperoxy) hexyne-3 is particularly preferred.

The blending amount of the component (d) is 0.01 to 3.0 parts by weight, preferably 0.1 to 1.5 parts by weight, based on 100 parts by weight of the components (a) and (b) in total. is there. If the blending amount is less than 0.01 part by weight, sufficient crosslinking cannot be achieved and the resulting elastomer has low abrasion resistance. On the other hand, if it exceeds 3.0 parts by weight, moldability becomes poor.

(5) Silica sol or colloidal silica component (e) In the thermoplastic elastomer composition of the present invention, a silica sol or colloidal silica component (e) may be added, if necessary, to improve the abrasion resistance of the product. It can be added. In colloidal silica, when the negatively charged silica particles are alkaline, the silanol groups on the surface of the silica particles are bound to hydroxide ions, so that these negatively charged silica particles repel each other. Fit,
Stable as a solution without binding. Sodium hydroxide or ammonium hydroxide is used as the alkaline agent. The silica particles are amorphous, have a high density, and are highly pure spheres, have a density of 2.1 to 2.2 g / cm ³ , and a particle size of 1
It is preferably 0 to 20 μm. When the silica sol is dried, the hydroxyl groups on the surface are dehydrated to release water. As such a silica sol, Adelite AT series is commercially available from Asahi Denka Kogyo Co., Ltd.

The blending amount of the component (e) is as follows.
0.5 with respect to 100 parts by weight of the total of the components (a) and (b).
It is preferably from 15 to 15 parts by weight, more preferably from 1 to 10 parts by weight. If it is less than 0.5 part by weight, the abrasion resistance of the product is insufficient. If it exceeds 15 parts by weight, not only steam generation during kneading becomes remarkable but also silica agglomeration becomes remarkable and the appearance of the product deteriorates.

(6) Block copolymer and / or hydrogenated component thereof (f) In the elastomer composition of the present invention, the block copolymer and / or the block copolymer and / or the same can be added to the elastomer composition of the present invention to adjust flexibility, if necessary. The hydrogenate component (f) can be added. Block copolymer component and / or its hydrogenated component (f)
Is a block copolymer composed of at least two polymer blocks A containing an aromatic vinyl compound as a main component and at least one polymer block B containing a conjugated diene compound as a main component. For example, A-B-A, B-A-B
Examples thereof include a vinyl aromatic compound-conjugated diene compound block copolymer or a hydrogenated block copolymer thereof having a structure such as -A and A-B-A-B-A.

The above (hydrogenated) block copolymer (hereinafter,
The (hydrogenated) block copolymer means a block copolymer and / or a hydrogenated block copolymer. ) Is an aromatic vinyl compound in an amount of 5 to 60% by weight, preferably 20.
-50% by weight.

The polymer block A containing an aromatic vinyl compound as a main component preferably consists of an aromatic vinyl compound alone or 50% by weight or more, preferably 70% by weight or more of an aromatic vinyl compound and an optional component such as ( (Hydrogenated) conjugated diene compound (hereinafter, (hydrogenated) conjugated diene compound is a conjugated diene compound, and / or
(Which means a hydrogenated conjugated diene compound).

The polymer block B based on the (hydrogenated) conjugated diene compound preferably consists only of the (hydrogenated) conjugated diene compound or 50 weight parts of the (hydrogenated) conjugated diene compound. % Or more, preferably 70% by weight or more and a copolymer block of an optional component such as an aromatic vinyl compound.

The solution viscosity of the block copolymer (5% toluene solution, 77 ° F, ASTM D-2196) is in the range of 5 to 500 cps, preferably 20 to 300 cps.
Is.

The number average molecular weight of the hydrogenated block copolymer is
The range is preferably 5,000 to 1,500,000, more preferably 10,000 to 550,000, still more preferably 90,000 to 400,000, and the molecular weight distribution is 10 or less. The molecular structure of the block copolymer is
It may be linear, branched, radial or any combination thereof.

In the polymer block A mainly composed of the aromatic vinyl compound and the polymer block B mainly composed of the conjugated diene compound, the distribution of the units derived from the conjugated diene compound or the aromatic vinyl compound in the molecular chain. May be random, tapered (in which the monomer component increases or decreases along the molecular chain), partially block-shaped, or any combination thereof. When there are two or more polymer blocks A mainly containing an aromatic vinyl compound or polymer blocks B mainly containing a conjugated diene compound, each polymer block may have the same structure or different structures. It may be.

As the aromatic vinyl compound constituting the (hydrogenated) block copolymer, for example, one kind or two or more kinds selected from styrene, α-methylstyrene, vinyltoluene, p-tert-butylstyrene and the like can be used. It can be selected, and styrene is preferable. Further, as the conjugated diene compound, for example, one kind or two or more kinds are selected from butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like. Among them, butadiene, isoprene and Combinations of these are preferred.

In the polymer block B mainly composed of the conjugated diene compound in the hydrogenated block copolymer, its microstructure is arbitrary. For example, when the block B is composed of butadiene alone, in the polybutadiene block, 1,2-microstructure is preferably 20-50
%, Particularly preferably 25 to 45% by weight. The hydrogenation rate is arbitrary, but is preferably 50% or more, more preferably 55% or more, still more preferably 60% or more. Alternatively, the 1,2-bond may be selectively hydrogenated. If block B is composed of a mixture of isoprene and butadiene, the 1,2-microstructure is preferably 5
It is less than 0%, more preferably less than 25%, even more preferably less than 15%. When block B is composed of isoprene alone, in the polyisoprene block,
Preferably 70-100% by weight of isoprene is 1,4-
Those having a microstructure and preferably at least 90% of the aliphatic double bonds derived from isoprene are hydrogenated.

When a hydrogenated block copolymer is used depending on the application, the above hydrogenated product can be preferably used appropriately according to the application.

Specific examples of the above (hydrogenated) block copolymer include styrene-butadiene-styrene copolymer (S
BS), styrene-isoprene-styrene copolymer (S
IS), styrene-isoprene-butadiene-styrene copolymer (SIBS), styrene-ethylene-butene-
Styrene copolymer (SEBS), styrene-ethylene-
Propylene-styrene copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene copolymer (SEEPS), styrene-butadiene-butylene-styrene copolymer (partially hydrogenated styrene-butadiene-
Examples thereof include a styrene copolymer and SBBS).

Many methods have been proposed as a method for producing these (hydrogenated) block copolymers, and a typical method is, for example, the method described in Japanese Patent Publication No. 40-23798. It can be obtained by block polymerization in an inert medium using a lithium catalyst or a Ziegler type catalyst.

The blending amount of the component (f) is as follows.
1 to 3 relative to 100 parts by weight of the total of the components (a) and (b).
The amount is preferably 5 parts by weight, more preferably 5 to 30 parts by weight. If the compounding amount is less than 1 part by weight, there is no effect of addition and 3
If it exceeds 5 parts by weight, abrasion resistance is lowered and moldability is deteriorated.

(7) Peroxide-decomposable olefin-based resin component (g) The thermoplastic elastomer composition of the present invention contains a peroxide-decomposable olefin-based resin component in order to improve heat resistance and moldability, if necessary. A resin component (g) can be added. The component (g) improves the rubber dispersion of the obtained thermoplastic elastomer composition, improves the appearance of the molded product, and has the effect of adjusting the hardness and the shrinkage ratio. The component (g) is an olefin-based polymer or copolymer that is thermally decomposed by heat treatment in the presence of peroxide to reduce the molecular weight and increases the fluidity at the time of melting, and is, for example, isotactic. Polypropylene or propylene and other α-olefins such as ethylene, 1
-Butene, 1-hexene, 4-methyl-1-pentene,
Examples thereof include copolymers with 1-octene and the like.

The melting point of the homopolymerized portion of the olefinic copolymer by DSC measurement is preferably Tm of 150.
˜170 ° C., ΔHm in the range of 25 to 90 mJ / mg. The crystallinity can be estimated from Tm and ΔHm measured by DSC. When Tm and ΔHm are out of the above ranges, the oil resistance and rubber elasticity at 100 ° C. or higher of the obtained elastomer composition are not improved.

Further, the melt flow rate of component (g) (MFR, ASTM D-1238, L condition, 230
C) is preferably 0.1 to 200 g / 10 minutes, more preferably 0.5 to 100 g / 10 minutes. When the MFR is less than 0.1 g / 10 minutes, the moldability of the obtained elastomer composition is deteriorated, and when it exceeds 200 g / 10 minutes, the mechanical strength of the obtained elastomer composition is reduced.

The blending amount of the component (g) is as follows.
1 to 30 based on 100 parts by weight of the components (a) and (b) in total.
It is preferably part by weight, more preferably 3 to 10 parts by weight. If it is less than 1 part by weight, there is no effect of addition, and if it exceeds 30 parts by weight, the abrasion resistance and moldability of the obtained elastomer composition deteriorate.

(8) Other Components In addition to the above components, the thermoplastic elastomer composition of the present invention may further contain various antiblocking agents, sealability improving agents, heat stabilizers, and oxidants, if necessary. It is also possible to contain an inhibitor, a light stabilizer, an ultraviolet absorber, a lubricant, a crystal nucleating agent, a coloring agent and the like. Here, as the antioxidant,
For example, 2,6-di-tert-p-butyl-p-cresol, 2,6-di-tert-butylphenol,
2,4-dimethyl-6-tert-butylphenol,
Examples thereof include phenolic antioxidants such as 4,4-dihydroxydiphenyl and tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, phosphite antioxidants, and thioether antioxidants. Of these, phenol-based antioxidants and phosphite-based antioxidants are particularly preferable. The antioxidant is the above component (a).
To (g) are preferably 0 to 3.0 parts by weight, and particularly preferably 0.1 to 1.0 parts by weight, based on 100 parts by weight.

2. Production of Thermoplastic Elastomer Composition The thermoplastic elastomer composition of the present invention comprises the above components (a) to (d) or, if necessary, components (e) to (g).
And the like, and each component is added at the same time or in an arbitrary order, and the mixture is melt-kneaded.

The melt-kneading method is not particularly limited, and a generally known method can be used. For example, a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer or various kneaders can be used. For example, a moderate L / D twin-screw extruder,
The above operation can be continuously performed by using a Banbury mixer, a pressure kneader or the like. Here, the temperature of the melt-kneading is preferably 160 to 220 ° C.

3. Uses of Thermoplastic Elastomer Composition The thermoplastic elastomer composition of the present invention is excellent in wear resistance, oil resistance, extrusion moldability, injection moldability, and surface gloss of a molded article, and therefore has door trim, quarter trim, luggage side trim, armrest. , Back door, instrument panel, instrument panel safety pad, overhead console, seat back, package tray, parcel shelf, damper, trunk box lid, pillar, grill garnish, engine undercover, roof box, etc. It can be used as a construction material such as joint packing, a refrigerator door packing, a home appliance material such as a pants press and an air conditioner panel, a rubber plug for infusion, a medical material such as a co-injectable pipe, and it is particularly necessary to have a design property. Can be used as a skin material .

[0053]

EXAMPLES The present invention will be specifically described with reference to the following examples and comparative examples, but the present invention is not limited to these examples. The measuring methods of physical properties and samples used in the present invention are shown below.

1. Physical property measuring method (1) Specific gravity: In accordance with JIS K 7112, a 1 mm thick sheet was used as a test piece. (2) Hardness: According to JIS K 6253, a 6.3 mm thick sheet was used as a test piece. (3) Tensile strength: In accordance with JIS K 6251, a test piece was a 1 mm thick sheet punched into a No. 3 mold with a dumbbell and used. The pulling speed was 500 mm / min. (4) 100% elongation stress: Based on JIS K 6251, a test piece was a 1 mm thick sheet punched into a No. 3 mold with a dumbbell and used. The pulling speed was 500 mm / min. (5) Elongation at break: Based on JIS K 6251, a test piece was a 1 mm thick sheet punched into a No. 3 mold with a dumbbell and used. The pulling speed was 500 mm / min. (6) Volume change rate: Based on JIS K 6258, a test piece having a thickness of 1 mm was punched into a No. 3 mold with a dumbbell and used. Using IRM # 902 oil, the weight change at 100 ° C. for 72 hours was measured. (7) Taber abrasion test: In accordance with JIS K 6264, a 2 mm thick sheet was used as a test piece, and an abrasion wheel H-2 was used.
2, load 1000g, wear amount after 1000 rotations (mg)
Was measured. (8) Extrudability: A 50 mm × 1 mm sheet was extruded and the drawdown property, surface appearance and shape were observed and evaluated according to the following criteria. ◯: Good ×: Poor (9) Injection moldability: A 130 mm × 130 mm × 2 mm sheet was injection-molded, the appearance was visually observed, and the presence or absence of flow marks and sink marks was evaluated according to the following criteria. ○: Good ×: Bad

2. Sample (1) olefin copolymer rubber component (a) used in Examples and Comparative Examples: ethylene-
Butene copolymer (EBR); Esprene N0441 (manufactured by Sumitomo Chemical Co., Ltd.) MFR: 1.3 g / 10 minutes (1
90 ° C), butene content: 30%, Mooney viscosity (ML
_{1 + 4} (100 ° C.)) = 25 (2) Ethylene polymer (b-1): HDPE-HB-
214R (manufactured by Nippon Polychem Co., Ltd.), crystallinity: Tm
130 ° C, △ Hm106mJ / mg, MFR0.05g
/ 10 minutes (190 ° C., 2.16 kg) (3) Ethylene polymer (b-2): EVA-Evaflex 40LX (manufactured by Mitsui DuPont Polychemical Co., Ltd.), M
FR 2.0g / 10 minutes (190 ° C, 2.16kg), V
A content 41 wt% (4) Cross-linking assistant component (c): Monoacrylate CB-
1 (trademark; manufactured by Shin-Nakamura Chemical Co., Ltd.), molecular weight 278, viscosity 3200 (CPS / 25 ° C.) (5) Organic peroxide component (d): Perhexa 25B (trademark; manufactured by NOF Corporation) (6) Colloidal Silica (e): Adelite AT-
20Q (manufactured by Asahi Denka Kogyo Co., Ltd.), SiO ₂ : 20 to ₂
1%, pH (25 ° C): 2.5 to 4.5, particle size: 10
˜20 μm, specific gravity: 1.12 to 1.14 (7) SBS block copolymer component (f): VECTO
R2518 (trademark; manufactured by DEXCO POLYMERS), styrene content: 30 wt%, solution viscosity 75 cp
s (5% toluene solution, 77 ° F, ASTM D-21
96) (8) Peroxide-decomposing olefin resin component (g): PP-BC8 (trademark; manufactured by Nippon Polychem Co., Ltd.), crystallinity: Tm166 ° C, ΔHm82mJ / m.
g, MFR 1.8 g / 10 min (9) Hindered phenol / phosphite / lactone-based composite antioxidant component (h): HP2215 (trademark;
(Ciba Specialty Chemicals)

Examples 1 to 4 and Comparative Examples 1 to 6 Using the amounts of the respective components shown in Tables 1 and 2, the formulations were put into a 20-liter pressure kneader, and the vapor pressure was 3. Kneading was performed for 10 minutes until the temperature reached 0 kg / cm ² and 180 ° C. Then, L / D = 20 having a rotary cutter at the tip, kneading temperature 140 ° C., screw rotation speed 8
Pelletized with a single screw extruder at 0 rpm. Next, the obtained pellets were injection-molded to prepare test pieces, which were subjected to respective tests. The evaluation results are shown in Tables 1 and 2.

[0057]

[Table 1]

[0058]

[Table 2]

As is clear from Tables 1 and 2, Examples 1 to 4 are the thermoplastic elastomer compositions of the present invention. Regardless of the presence or absence of optional components (e) to (g), all the thermoplastic elastomer compositions showed good properties. Further, in Examples 2 and 3, the component (f)
Of Tuftec P JT-90C (styrene-butadiene / butylene-styrene copolymer manufactured by Asahi Kasei; SBBS, styrene content 30% by weight, weight average molecular weight (Mw): 110,000, number average molecular weight ( M
n): 99,000, molecular weight distribution: 1.11, butadiene block hydrogenation rate: 75.1%, (1,2-butadiene hydrogenation rate 92.7%, 1,4-butadiene hydrogenation rate 61.0%)), and similarly good results were obtained. The hydrogenation rate is ¹ H-
It was measured by NMR measurement.

The method for measuring the hydrogenation rate of the conjugated diene block portion was as follows: A sample was taken in an NMR sample tube (5 mmφ), deuterated chloroform was added, and the sample was sufficiently dissolved. Nuclear magnetic resonance apparatus (NMR) manufactured by JEOL room temperature using a GSX-400 type, at 400 MHz, 3029 times of integration ¹ H-
NMR measurement was performed.

On the other hand, in Comparative Examples 1 and 2, the components (a) and (b) were out of the range. When the amount of the component (a) was small (the amount of the component (b) was large), the flexibility was lowered and the molding was performed. Sex deteriorates. When the amount of the component (a) is large (the amount of the component (b) is small), abrasion resistance, oil resistance, mechanical properties and moldability are deteriorated. Comparative Example 3
And 4 are those in which the component (c) is out of the range. When the component (c) is small, the wear resistance deteriorates, and when the component (c) is large, the oil resistance, the wear resistance, and the moldability deteriorate. . Comparative Examples 5 and 6 are those in which the component (d) is out of the range. When the component (d) is small, oil resistance and wear resistance are deteriorated, and when the component (d) is large, mechanical properties and moldability are deteriorated. Getting worse.

[0062]

EFFECT OF THE INVENTION The thermoplastic elastomer composition of the present invention is a polyolefin-based thermoplastic elastomer composition having excellent wear resistance, oil resistance, extrusion moldability, and injection moldability. It can be used as a member for household appliances and a member for household appliances, and in particular, it can be used as a skin material that requires designability.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08K 5/14 C08K 5/14 C08L 23/04 C08L 23/04 F term (reference) 3D023 BA01 BB08 BC01 BD03 BE02 4J002 BB00W BB00Z BB02X BB03X BB04W BB04X BB11W BB15W BP01Y DJ018 EH076 EK007 FD156 GL00 GN00 GQ00

Claims (8)

[Claims] 1. (a) Olefin-based copolymer rubber: 10
To 90% by weight, (b) ethylene polymer: 10 to 90% by weight, (c) ester crosslinking agent: 0.01 to 10 parts by weight per 100 parts by weight of the total of components (a) and (b). Parts, and (d) organic peroxide: 100 in total of components (a) and (b)
A thermoplastic elastomer composition obtained by melt-kneading a composition containing 0.01 to 3.0 parts by weight with respect to parts by weight. 2. The thermoplastic elastomer composition according to claim 1, wherein the (a) olefin copolymer rubber has a Mooney viscosity (ML 1 _{+ 4} (100 ° C.)) of 7 to 75. 3. The thermoplastic elastomer composition according to claim 1, wherein at least a part of the (b) ethylene polymer is a polyethylene resin. 4. The thermoplastic elastomer composition according to claim 1, wherein the ester-based crosslinking aid (c) is a monoacrylate. 5. (e) Silica sol or colloidal silica: 100 parts by weight of the total of components (a) and (b),
The thermoplastic elastomer composition according to claim 1, further comprising 0.5 to 15 parts by weight. 6. (f) A block copolymer comprising at least two polymer blocks A mainly containing an aromatic vinyl compound and at least one polymer block B mainly containing a conjugated diene compound, and / Or a hydrogenated block copolymer obtained by hydrogenating it: 1 to 35 parts by weight per 100 parts by weight of the components (a) and (b) in total. The thermoplastic elastomer composition according to. 7. The (g) peroxide-decomposable olefin resin: 1 to 30 parts by weight per 100 parts by weight of the components (a) and (b) in total, further comprising 1 to 30 parts by weight. The thermoplastic elastomer composition according to. 8. An automobile interior / exterior member, a building member, or a home appliance member, which is formed by molding the thermoplastic elastomer composition according to any one of claims 1 to 7.