JP2003003038A - Thermoplastic elastomer composition and production method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer composition which can be produced in a simple melt-kneading process and which is excellent in flexibility, rubber elasticity under high temperature, mechanical strengths, oil resistance, solvent resistance, thermal resistance, weather resistance and surface properties. SOLUTION: The thermoplastic elastomer composition contains a hydrogenated block copolymer (a) having a number average molecular weight of 200,000 or more and having a vinyl aromatic compound polymer block and a hydrogenated conjugated diene compound polymer block, a non-hydrogenated block copolymer (b) having a vinyl aromatic compound polymer block and a conjugated diene compound polymer block, a non-aromatic rubber softening agent (c), a peroxide cross-linked olefin resin (d) having a density of 0.94 g/cm<3> or more, a peroxide decomposition type olefin resin (e), an organic peroxide (f) and a cross linking auxiliary agent (g). The composition is obtained by dynamic-crosslinking a mixture where the blend ratio of the (a) to the (b) is from 85:15 to 99:1, the (c) is blended in an amount of from 50 to 250 parts by mass and the (d) is blended in an amount of from 2.5 to 50 parts by mass per 100 parts by mass in total of the (a) and the (b), and the (e) is blended in an amount of from 0.5 to 10 mass times of the (d).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermoplastic elastomer composition and a method for producing the same. More specifically,
INDUSTRIAL APPLICABILITY The present invention can be produced by a simple melt-kneading process, is excellent in flexibility, has excellent rubber elasticity, particularly rubber elasticity at high temperature and has a very small compression set, and further has high-temperature creep performance, mechanical strength, and oil resistance. , Solvent resistance, heat resistance, weather resistance,
The present invention relates to a thermoplastic elastomer composition having excellent surface properties of a molded article obtained and a method for producing the same. The thermoplastic elastomer composition of the present invention can be effectively used as a material for various molded products by utilizing these excellent properties.

[0002]

2. Description of the Related Art Thermoplastic elastomers do not require a vulcanization step and can be molded in the same manner as thermoplastic resins, so in recent years, automobile parts, home electric appliance parts, wire coatings, medical parts, footwear miscellaneous goods, It is used in a wide range of fields such as toys, sports equipment and daily necessities. Among thermoplastic elastomers, polystyrene-polybutadiene-polystyrene block copolymer (SBS), polystyrene-polyisoprene-polystyrene block copolymer (SIS), and styrene-based thermoplastic elastomers represented by hydrogenated products thereof are It is widely used because it is inexpensive and has excellent hydrolysis resistance.

Hydrogenated products of polystyrene-polybutadiene-polystyrene block copolymers and polystyrene-
A hydrogenated product of a block copolymer having a vinyl aromatic compound polymer block and a conjugated diene compound polymer block, represented by a hydrogenated product of a polyisoprene-polystyrene block copolymer, is a vinyl aromatic compound polymer block. It is a block copolymer having a conjugated diene compound polymer block and the lack of heat resistance and weather resistance is improved by hydrogenation, but it is inferior in rubber elasticity at high temperature, compression set at high temperature large.

In order to improve the above points, Japanese Patent Laid-Open No. 59-62.
No. 36 discloses that (a-1) two or more vinyl aromatic compound polymer blocks and a conjugated diene compound polymer block 1
100 parts by weight of a hydrogenated product of a block copolymer having 1 or more, (a-2) 20 to 150 parts by weight of a peroxide-crosslinked olefin copolymer rubber, (a-3) a peroxide non-crosslinked hydrocarbon-based rubber 0 to 50 parts by weight of rubber, (a-
4) 80 to 300 parts by weight of a non-aromatic softening agent for rubber, (a-5) peroxide decomposing olefin resin 30 to 4
00 parts by weight and 0 to 900 parts by weight of the (a-6) inorganic filler, first of all components other than the component (a-1), at least the total amount of the component (a-2) is an organic peroxide. A method for producing an elastomeric composition by heat-treating in the presence to dynamically crosslink and then blending the dynamically crosslinked product with component (a-1) and the remaining components is described. And, in this publication, it is explained that the mechanical strength of the elastomeric composition is significantly reduced when the multi-step partial crosslinking-compounding step described above is not adopted.

Further, JP-A-8-225713 discloses a block copolymer having two or more (ro-1) vinyl aromatic compound polymer blocks and one or more conjugated diene compound polymer blocks and / or a block copolymer thereof. 100 parts by weight of hydrogenated product, (B-2) Softener for non-aromatic rubber 40 to 300
Parts by weight, (b-3) peroxide crosslinked olefin resin and / or copolymer rubber containing the same 1.0 to 1
00 parts by weight, (b-4) peroxide-decomposing olefin resin and / or copolymer containing 10 to 15
In the method for producing a thermoplastic elastomer resin composition containing 0 part by weight, components (b-1) and (b-2), at least a part of the component (b-3), and a part of the component (b-4). Is heat-treated in the presence of an organic peroxide to crosslink, and then the crosslinked product and the balance of the component (b-4) or the component (b-3) and the balance of the component (b-4) are blended. A method of making a plastic elastomer resin composition is described. And, in this publication, a composition dynamically crosslinked in the presence of an organic peroxide and a component (ro-
It is described that 4) is compatible with each other and micro-dispersed in the composition to improve the processing characteristics, fluidity, mechanical strength and the like of the obtained thermoplastic elastomer resin composition. However, in any of the methods described in each publication, it is not possible to dynamically crosslink each component at a final blending ratio at once, and after dynamically crosslinking a part of the constituent components, the remaining components are blended. However, the manufacturing process of the thermoplastic elastomer resin composition is very complicated, and the rubber elasticity at high temperature is still insufficient.

[0006]

The object of the present invention is to provide a hydrogenated product of a block copolymer having a vinyl aromatic compound polymer block and a conjugated diene compound polymer block, a softening agent for a non-aromatic rubber, and a peroxide. A thermoplastic elastomer composition obtained by dynamically cross-linking a mixture containing an oxide-crosslinking olefin resin and a peroxide-decomposing olefin resin in the presence of an organic peroxide, in the prior art described in the above publication. It is an object of the present invention to provide a dynamically crosslinked thermoplastic elastomer composition excellent in various properties, which does not necessarily require such a multi-step partial cross-linking-blending step and can be obtained by any heating and kneading step including one step. In particular, it is excellent in flexibility, rubber elasticity, especially rubber elasticity at high temperature, compression set is extremely small, high temperature creep performance, mechanical strength, oil resistance, solvent resistance, heat resistance, weather resistance, It is an object of the present invention to provide a dynamically crosslinked thermoplastic elastomer composition capable of producing a molded article having excellent surface properties and the like. And an object of the present invention is to provide a method for producing a thermoplastic elastomer composition having the above-mentioned excellent properties.

[0007]

Means for Solving the Problems The present inventors have made extensive studies in order to achieve the above object. As a result, a hydrogenated product of a block copolymer having a vinyl aromatic compound polymer block and a conjugated diene compound polymer block, a non-aromatic softening agent for rubber, a peroxide cross-linking olefin resin, and a peroxide decomposing type Hydrogenation of a block copolymer having a vinyl aromatic compound polymer block and a conjugated diene compound polymer block in a thermoplastic elastomer composition obtained by dynamically crosslinking a mixture containing an olefin resin in the presence of an organic peroxide. As well as using those having a specific range of molecular weight,
A non-hydrogenated block copolymer having a non-hydrogenated vinyl aromatic compound polymer block and a conjugated diene compound polymer block is used in combination, and a peroxide-crosslinking olefin resin having a specific density is used. Hydrogenated block copolymer, non-hydrogenated block copolymer, a softening agent for non-aromatic rubber, peroxide cross-linking olefin-based resin and peroxide decomposition type olefin-based resin compounding amount within a specific range , The multi-step dynamic crosslinking-compounding step as in the prior art described in the above two publications becomes unnecessary, and the dynamic cross-linking heat having good characteristics in any heating and kneading step including one step. It has been found that a plastic elastomer composition can be obtained. In particular, the dynamically crosslinked thermoplastic elastomer composition and molded articles obtained therefrom have excellent flexibility, and also have excellent rubber elasticity, particularly rubber elasticity at high temperature, and even when compressed for a long time at high temperature, Extremely low compression set, high temperature creep performance, mechanical strength, oil resistance, solvent resistance,
The present invention has been completed by finding that it has excellent properties such as heat resistance and weather resistance, and that it has a good appearance without surface roughness and bleeding out of the softening agent to the surface.

That is, the present invention provides (1) (i) at least one polymer block A ₁ containing a vinyl aromatic compound as a main component and at least one polymer block B ₁ containing a conjugated diene compound as a main component. A hydrogenated block copolymer (a) having a number average molecular weight of 200,000 or more obtained by hydrogenating a block copolymer having the same, at least one polymer block A ₂ mainly composed of a vinyl aromatic compound, and a conjugated diene. A non-hydrogenated non-hydrogenated block copolymer (b) having at least one polymer block B ₂ mainly composed of a compound, a non-aromatic softening agent for rubber (c), and a density of 0.94 g / cm 3. Contains ^three or more peroxide-crosslinking olefin-based resins (d), peroxide-decomposing olefin-based resins (e), organic peroxides (f), and crosslinking aids (g); and , (Ii) the blending ratio of the hydrogenated block copolymer (a): the non-hydrogenated block copolymer (b) is 85:15 to 99: 1 (mass ratio); (iii)
The compounding amount of the non-aromatic softening agent for rubber (c) is 50 to 250 parts by mass with respect to a total of 100 parts by mass of the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b). And (iv) the amount of the peroxide-crosslinked olefin resin (d) is 100 parts by mass based on 100 parts by mass of the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b). 2.5 to 50 parts by mass; and (v) the amount of the peroxide-decomposing olefin resin (e) is
0.5 to 10 times the compounding amount of the peroxide-crosslinking olefin resin (d);
A thermoplastic elastomer composition characterized by being dynamically crosslinked.

The present invention also provides (2) a hydrogenated block copolymer (a), a non-hydrogenated block copolymer (b), a non-aromatic rubber softening agent (c), and a peroxide cross-linked olefin. A mixture containing the resin-based resin (d), the peroxide-decomposable olefin-based resin (e), the organic peroxide (f), and the crosslinking aid (g) in a single step is melted and kneaded under heating. It is the above-mentioned thermoplastic elastomer composition (1).

Further, the present invention provides (3) (i) vinyl
Polymer block A mainly composed of aromatic compounds₁A little
Polymers mainly containing at least one and conjugated diene compound
Block B₁Block copolymer having at least one
Hydrogenated hydrogen peroxide having a number average molecular weight of 200,000 or more
Mainly composed of lock copolymer (a) and vinyl aromatic compound
Polymer block A ₂And at least one
Polymer block B mainly composed of₂At least
Non-hydrogenated non-hydrogenated block copolymer with one
Body (b), non-aromatic softener for rubber (c), density of 0.
94 g / cm³The above peroxide-crosslinked olefins
Resin (d), peroxide decomposition type olefin resin
(E), organic peroxide (f), and crosslinking aid
(G); and (ii) hydrogenated block copolymer
(A): The blending ratio of the non-hydrogenated block copolymer (b) is
85:15 to 99: 1 (mass ratio); (iii) non
The blending amount of the softening agent (c) for aromatic rubber is a hydrogenated block.
Sum of copolymer (a) and non-hydrogenated block copolymer (b)
50 to 250 parts by mass with respect to 100 parts by mass;
(Iv) Peroxide cross-linking olefin resin (d)
The content of the hydrogenated block copolymer (a) and the non-hydrogenated block
1. With respect to 100 parts by mass of the total copolymer (b), 2.
5 to 50 parts by mass; and (v) peroxide
The amount of decomposing olefin resin (e) is
0.5 of the amount of the side-crosslinking olefin resin (d) compounded
-10 times by mass; a mixture consisting of
It is characterized in that it is melt-kneaded and dynamically crosslinked under heating
And a method for producing a thermoplastic elastomer composition.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The hydrogenated block copolymer (a) used in the present invention is
Hydrogenated block obtained by hydrogenating a block copolymer having at least one vinyl aromatic compound-based polymer block A ₁ and at least one conjugated diene compound-based polymer block B ₁ It is a copolymer.
In the hydrogenated block copolymer (a), the vinyl aromatic compound constituting the polymer block A ₁ is, for example,
Styrene, α-methylstyrene, o-methylstyrene,
m-methylstyrene, p-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene, 2,4,6
-Trimethylstyrene, monofluorostyrene, difluorostyrene, monochlorostyrene, dichlorostyrene, vinylnaphthalene, vinylanthracene, etc., and the polymer block A ₁ is formed of one or more of these vinyl aromatic compounds. Can have been. Among them, the polymer block A ₁ is preferably formed of styrene. The polymer block A ₁ may be an unsaturated monomer other than the vinyl aromatic compound (for example, 1-butene, pentene, hexene, 1,3) unless the objects and effects of the present invention are impaired.
-Butadiene, isoprene, methyl vinyl ether, methyl methacrylate, vinyl acetate, etc.) may be contained in a small amount (preferably 10% by mass or less of the polymer block A ₁ ) of one or more structural units derived from .

The conjugated diene compound constituting the polymer block B ₁ in the hydrogenated block copolymer (a) includes 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene and 1-butadiene. , 3-pentadiene,
1,3-hexadiene and the like can be mentioned, and the polymer block B ₁ can be formed of one kind or two or more kinds of these conjugated diene compounds. Among them, the polymer block B ₁ is preferably formed of either one of 1,3-butadiene and isoprene or both of them, and the surface tackiness of the resulting thermoplastic elastomer composition is From the viewpoint of reduction, it is particularly preferable that it is formed from both 1,3-butadiene and isoprene.

The binding form of the conjugated diene compound in the polymer block B ₁ is not particularly limited. For example, 1,3-
1,2-bond and / or 1,4 in the case of butadiene
In the case of -bond, isoprene, 1,2-bond, 3,4-bond and / or 1,4-bond can be adopted, and any of these bond forms may be used. Of which
When the polymer block B ₁ is formed of 1,3-butadiene, the ratio of 1,2-bonds is 20 to 70 mol%.
And the proportion of 1,4-bonds is preferably 30 to 80 mol%. When the polymer block B is formed of isoprene or isoprene and 1,3-butadiene, the total of 3,4-bonds and 1,2-bonds is 5 to 70 mol%. Preferably there is.

When the polymer block B ₁ is formed of two or more kinds of conjugated diene compounds (for example, 1,3-butadiene and isoprene), their bonding form is
It can be completely alternating, random, tapered, partially blocky, or a combination of two or more thereof.

In the polymer block B ₁ , some or all of the carbon-carbon double bonds based on the conjugated diene compound must be hydrogenated (hydrogenated). The hydrogenation rate is not particularly limited, but from the viewpoint of heat resistance and weather resistance, it is preferable that 85 mol% or more of the carbon-carbon double bond based on the conjugated diene compound be hydrogenated, and 90 mol% or more. It is more preferably hydrogenated. The hydrogenation rate is based on the value of carbon-based on the conjugated diene compound in the polymer block B _1.
The content of the carbon double bond can be determined by measuring the iodine value before and after the hydrogenation by iodine value measurement, infrared spectrophotometer, ¹ H-NMR spectrum and the like.

The polymer block B ₁ may be an unsaturated monomer other than the conjugated diene compound (eg 1-butene, 1-butene, 1-butene, 1-butene, etc.) as long as it does not interfere with the objects and effects of the present invention.
Pentene, 1-hexene, methyl vinyl ether, styrene, methyl methacrylate, vinyl acetate, etc.) has a small amount of one or more structural units derived from (preferably 10% by mass or less of the polymer block B ₁ ). May be.

At least the hydrogenated block copolymer (a) is used.
Also one polymer block A₁And at least one polymer
Block B₁It is a hydrogenated product of block copolymer in which and are combined.
As far as possible, the bond type of the polymer block is limited.
Straight, branched, radial, or two or more thereof
Either of the combined forms may be used. Those
However, polymer block A₁And polymer block B₁Join
The format is preferably linear, for example, polymerization
Body block A₁A₁And again polymer block B ₁To B₁so
When expressed, A₁-B₁Hydrogenation of Diblock Copolymer
Thing, A₁-B₁-A ₁A hydrogenated product of a triblock copolymer of
A₁-B₁-A₁-B₁Hydrogenation of Tetrablock Copolymer
Thing, A₁-B₁-A₁-B₁-A₁Pentablock copolymerization of
Examples include hydrogenated products of the body. Among them
Also A₁-B₁Hydrogenated products of diblock copolymers and / or
Or A₁-B₁-A₁Hydrogenated products of triblock copolymer
However, it is easy to manufacture the block copolymer and flexibility
Preferably used from

The content of the structural unit derived from the vinyl aromatic compound in the hydrogenated block copolymer (a) is in the range of 10 to 65 mass% from the viewpoint of mechanical strength and flexibility of the thermoplastic elastomer composition. Preferably within 1
More preferably, it is in the range of 5 to 35 mass%. The content of structural units derived from the vinyl aromatic compound in the block copolymer including the hydrogenated block copolymer (a) can be determined by ¹ H-NMR spectrum or the like.

The hydrogenated block copolymer (a) is
The number average molecular weight after hydrogenation is required to be 200,000 or more, preferably 250,000 or more. When the number average molecular weight of the hydrogenated block copolymer (a) is less than 200,000,
The rubber elasticity of the thermoplastic elastomer composition at high temperatures is reduced. The upper limit of the number average molecular weight of the hydrogenated block copolymer (a) is not particularly limited, but it is preferably 500,000 or less from the viewpoint of moldability of the thermoplastic elastomer composition. The number average molecular weight referred to in the present specification is a polystyrene-equivalent molecular weight determined by gel permeation chromatography (GPC) measurement.

As long as the hydrogenated block copolymer (a) does not impair the gist of the present invention, the hydrogenated block copolymer (a) may be used in the molecular chain and / or
Alternatively, one or two functional groups such as a carboxyl group, a hydroxyl group, an acid anhydride group, an amino group and an epoxy group may be attached to the terminal of the molecule.
It may have more than one species.

Furthermore, the thermoplastic elastomer composition of the present invention contains the above-mentioned hydrogenated block copolymer (a),
Non-hydrogenated non-hydrogenated block copolymer (b) having at least one polymer block A ₂ mainly containing a vinyl aromatic compound and at least one polymer block B ₂ mainly containing a conjugated diene compound Contains. By including the non-hydrogenated block copolymer (b) having a carbon-carbon double bond derived from a conjugated diene compound in the molecule in the thermoplastic elastomer composition, the crosslinking reaction of the thermoplastic elastomer composition is promoted. As a result, the rubber elasticity at a high temperature becomes higher, and the compression set at a high temperature can be reduced.

In the non-hydrogenated block copolymer (b),
Polymer block A₂As a vinyl aromatic compound
Are, for example, styrene, α-methylstyrene, o-meth
Cylstyrene, m-methylstyrene, p-methylstyrene
Amine, pt-butyl styrene, 2,4-dimethylstyrene
2,4,6-trimethylstyrene, monofluoros
Tylene, difluorostyrene, monochlorostyrene, di
Chlorostyrene, vinyl naphthalene, vinyl anthrace
Polymer block A ₂Is this
Formed from one or more of these vinyl aromatic compounds
Can have been. Among them, the polymer block
Ku A₂Are preferably formed from styrene.
Polymer block A₂Hinders the objects and effects of the present invention.
Unless otherwise specified, vinyl aromatic compounds
External unsaturated monomers (eg 1-butene, pentene, hex
Sen, 1,3-butadiene, isoprene, methyl vinyl
Ether, methyl methacrylate, vinyl acetate, etc.)
A small amount of one or more of the incoming structural units (preferably
Is polymer block A₂10% by mass or less) of
Good.

In the non-hydrogenated block copolymer (b), the conjugated diene compound constituting the polymer block B ₂ is 1,3-butadiene, isoprene or 2,3-
Examples thereof include dimethyl-1,3-butadiene, 1,3-pentadiene, and 1,3-hexadiene, and the polymer block B ₂ is formed of one or more of these conjugated diene compounds. You can Among them, the polymer block B ₂ is preferably formed of either one of 1,3-butadiene and isoprene, or both.

The binding form of the conjugated diene compound in the polymer block B ₂ is not particularly limited. For example, 1,3-
1,2-bond and / or 1,4 in the case of butadiene
In the case of -bond, isoprene, 1,2-bond, 3,4-bond and / or 1,4-bond can be adopted, and any of these bond forms may be used. Of which
When the polymer block B ₂ is formed of 1,3-butadiene, the proportion of 1,2-bonds is 20 to 70 mol%.
And the proportion of 1,4-bonds is preferably 30 to 80 mol%. When the polymer block B is formed of isoprene or isoprene and 1,3-butadiene, the total of 3,4-bonds and 1,2-bonds is 5 to 70 mol%. Preferably there is.

When the polymer block B ₂ is formed of two or more kinds of conjugated diene compounds (for example, 1,3-butadiene and isoprene), their bonding form is
It can be completely alternating, random, tapered, partially blocky, or a combination of two or more thereof.

The polymer block B ₂ may be an unsaturated monomer other than the conjugated diene compound (eg, 1-butene, 1-butene, 1-butene, 1-butene) as long as it does not hinder the objects and effects of the present invention.
Pentene, 1-hexene, methyl vinyl ether, styrene, methyl methacrylate, vinyl acetate, etc.) in a small amount (preferably 10% by mass or less of the polymer block B) of one or more structural units derived from Good.

As long as at least one polymer block A ₂ and at least one polymer block B ₂ are bonded, the non-hydrogenated block copolymer (b) has a polymer block bonding form. Without limitation, linear, branched, radial,
Alternatively, it may be a combined form in which two or more of them are combined. Among them, it is preferable that the polymer block A ₂ and the polymer block B ₂ are bonded in a straight chain form. For example, the polymer block A ₂ is A ₂ and the polymer block B ₂ is when expressed in B _2, a ₂ diblock copolymer -B _2, a ₂ triblock copolymer _{-B 2 -A 2, a 2 -B} 2 -A 2 -B 2 of tetra-block copolymer Polymer,
_{A 2 -B 2 -A 2 -B 2} -A 2 penta block copolymer, and the like. Among them, A ₂ -B ₂
The diblock copolymer of and / or the triblock copolymer of A ₂ -B ₂ -A ₂ are preferably used in terms of easiness of production of the block copolymer and flexibility.

The content of the structural unit derived from the vinyl aromatic compound in the non-hydrogenated block copolymer (b) is from 10 to 65 in view of mechanical strength, flexibility and rubber elasticity of the thermoplastic elastomer composition. It is preferably in the range of mass% and more preferably in the range of 15 to 35 mass%.

The non-hydrogenated block copolymer (b) preferably has a number average molecular weight of 50,000 to 300,000.
It is more preferably 10,000 to 200,000. When the number average molecular weight of the non-hydrogenated block copolymer (b) is less than 50,000, the rubber elasticity of the thermoplastic elastomer composition at high temperature tends to be lowered, and the softening agent for non-aromatic rubber ( C) easily bleeds out. On the other hand, when the number average molecular weight of the non-hydrogenated block copolymer (b) exceeds 300,000, the fluidity of the thermoplastic elastomer composition becomes poor and the moldability deteriorates.

The non-hydrogenated block copolymer (b) may optionally contain a carboxyl group, a hydroxyl group, an acid anhydride group, an amino group, in the molecular chain and / or at the terminal of the molecule, as long as the gist of the present invention is not impaired. You may have 1 type (s) or 2 or more types of functional groups, such as an epoxy group.

The method for producing the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b) is not particularly limited and can be produced by a conventionally known method. For example, it may be produced by any of an ionic polymerization method such as anionic polymerization and cationic polymerization, a single-site polymerization method, a radical polymerization method and the like. In the case of the anionic polymerization method, for example, n-hexane, using an alkyl lithium compound or the like as a polymerization initiator,
A block copolymer is produced by a method such as sequential polymerization or coupling of a vinyl aromatic compound and a conjugated diene compound in an organic solvent inert to the polymerization reaction such as cyclohexane. The hydrogenated block copolymer (a) is obtained by hydrogenating the block copolymer obtained above in the presence of a hydrogenation catalyst in an inert organic solvent according to a known method. Also,
As the non-hydrogenated block copolymer (b), the block copolymer obtained above is used without being hydrogenated.

In the present invention, the hydrogenated block copolymer (a)
And non-hydrogenated block copolymer (b), (a): (b) =
It is necessary to use it in a mass ratio of 85:15 to 99: 1, and it is more preferable to use it in a mass ratio of 90:10 to 95: 5. The proportion of the hydrogenated block copolymer (a) is less than 85% by mass based on the total mass of the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b) [non-hydrogenated block Ratio of copolymer (b) exceeds 15% by mass]
And the thermoplastic elastomer composition is inferior in heat resistance, weather resistance and fluidity, while the proportion of the hydrogenated block copolymer (a) exceeds 99% by mass [non-hydrogenated block copolymer ( If the proportion of b) is less than 1% by mass], the crosslinking may not be sufficiently carried out, the rubber elasticity at a high temperature may decrease, the compression set may increase, and the moldability may decrease.

The thermoplastic elastomer composition of the present invention comprises
Further, it contains a non-aromatic softening agent for rubber (c). As the non-aromatic softening agent for rubber (c), any conventionally known non-aromatic softening agent for rubber can be used, and among them, non-aromatic mineral oil or oily or low molecular weight Synthetic softeners are suitable. The non-aromatic softening agent for rubber (c) may be used alone or in combination of two or more kinds. Generally, a mineral oil-based softening agent for rubber called process oil or extender oil, which is used for softening, increasing volume and improving processability of rubber, is a combination of aromatic ring, naphthene ring and paraffin chain. A mixture in which the number of carbon atoms in the paraffin chain accounts for 50% or more in the total number of carbon atoms is called paraffin-based, and the one in which the carbon number of the naphthene ring is 30 to 45% is naphthene-based or aromatic carbon. Those whose number is more than 30% are called aromatic. In the present invention, among the above-mentioned process oils, paraffin-based process oil and naphthene-based process oil can be used. In addition to them, white oil, mineral oil, low molecular weight copolymer (oligomer) of ethylene and α-olefin, paraffin wax, liquid paraffin and the like can be used. Among them, in the present invention, paraffin-based process oil and / or naphthene-based process oil are preferably used as the non-aromatic rubber softening agent (c).

When an aromatic rubber softening agent such as an aromatic process oil is used in place of the non-aromatic rubber softening agent (c), the hydrogenated block copolymer (a) is used.
Also, in the non-hydrogenated block copolymer (b), the block composed of the vinyl aromatic compound is attacked, and the physical properties of the thermoplastic elastomer composition, particularly mechanical strength and rubber elasticity cannot be improved.

The compounding amount of the non-aromatic softening agent for rubber (c) is 50 to 50 parts by weight based on 100 parts by mass of the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b). Two
The amount is required to be 50 parts by mass, preferably 80 to 200 parts by mass. When the compounding amount of the non-aromatic rubber softening agent (c) is less than 50 parts by mass described above, the flexibility of the thermoplastic elastomer composition is poor and the molding processability is deteriorated, while 250 parts by mass is added. When it exceeds
A molded product obtained from the thermoplastic elastomer composition has insufficient mechanical strength, and is a softening agent for non-aromatic rubber (c).
Bleed out of

The peroxide-crosslinkable olefin resin (d) used in the present invention means an olefin resin which is crosslinked by heat treatment in the presence of peroxide to increase its molecular weight. Examples of the peroxide-crosslinking olefin resin (d) include polyethylene, copolymers of ethylene with a small amount of propylene, 1-hexene, 1-octene, and the like, and one or more of these may be used. Can be used. Among them, polyethylene is preferably used from the viewpoint of exhibiting rubber elasticity at high temperature. The peroxide-crosslinking olefin resin (d) used in the present invention has a density of 0.94 g / cm ^3.
It is necessary to be above, and it is preferable to be 0.95 g / cm ³ or above. If the density of the peroxide-crosslinking olefin-based resin (d) is less than 0.94 g / cm ³ , the rubber elasticity of the thermoplastic elastomer composition will be insufficient at high temperatures, especially at high temperatures exceeding 100 ° C. Further, the peroxide-crosslinking olefin resin (d) is
The MFR is 10 ° C under the conditions of 190 ° C and 21.2N.
It is preferably 50 g / 10 minutes from the viewpoint of fluidity of the obtained thermoplastic elastomer composition, and 20 to 50 g.
More preferably, it is / 10 minutes.

The amount of the peroxide-crosslinking olefin resin (d) to be blended is 2.5 based on 100 parts by mass of the total of the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b). Is required to be 50 parts by mass and 5
It is preferably about 45 parts by mass. The mixing amount of the peroxide-crosslinking olefin resin (d) is the same as the above-mentioned 2.
When the amount is less than 5 parts by mass, the rubber elasticity of the thermoplastic elastomer composition at high temperature becomes insufficient and the compression set increases, while when it exceeds 50 parts by mass, the hardness of the thermoplastic elastomer composition becomes too high. And the flexibility is lost, and bleed-out of the softening agent (c) for non-aromatic rubber becomes remarkable, which is not desirable.

The peroxide-decomposable olefin resin (e) used in the present invention is an olefin resin which is thermally decomposed by heat treatment in the presence of peroxide to reduce its molecular weight and increase its fluidity. Say. Examples of the peroxide-decomposable olefin resin (e) include isotactic polypropylene, a copolymer of propylene and a small amount of other α-olefin such as ethylene, 1-butene, 1-hexene, and 1-octene. And one or more of these can be used. Among them, a copolymer of propylene and a small amount of α-olefin is preferably used from the viewpoint that the rubber elasticity of the thermoplastic elastomer composition is good, and particularly a block type is more preferably used.

The amount of the peroxide-decomposable olefin resin (e) to be blended must be 0.5 to 10 times the amount of the peroxide-crosslinking olefin resin (d), and 1 to 6 is required. It is preferably mass times. The amount of peroxide-decomposable olefin resin (e) is
When the amount is less than 0.5 times the amount of the peroxide-crosslinking olefin resin (d), the surface smoothness of the molded article obtained from the thermoplastic elastomer composition, particularly the injection-molded article, is lost, while 10% by weight is obtained. If it exceeds 2 times, the rubber elasticity of the thermoplastic elastomer composition at high temperature is lost and the compression set becomes large.

In the present invention, the organic peroxide (f) is used together with the above components. As the organic peroxide (f), any organic peroxide having a crosslinking action under dynamic conditions may be used, and either aromatic peroxide or aliphatic peroxide can be used. Further, one kind of organic peroxide may be used, or two or more kinds of organic peroxide may be used. Specific examples of the organic peroxide (f) that can be used in the present invention include 2,5-dimethyl-2,5-
Di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-
3,2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate,
Examples thereof include dicumyl peroxide, diisopropyl benzohydroperoxide, 1,3-bis (t-butylperoxyisopropyl) benzene, and benzoyl peroxide, and one or more of these can be used.

The amount of the organic peroxide (f) used is not limited in a strict sense, but it is usually the above-mentioned components (a) to (a).
The total amount of (e) is preferably 0.3 to 1.5 parts by mass, and more preferably 0.5 to 1.0 part by mass, based on 100 parts by mass. When the amount of the organic peroxide (f) used is less than the above-mentioned 0.3 parts by mass, the rubber elasticity of the thermoplastic elastomer composition at high temperature tends to be insufficient and the compression set tends to increase. While 1.5
When the amount is more than parts by mass, the fluidity of the thermoplastic elastomer composition is lowered, the moldability is lowered, and the surface roughness of the obtained molded article tends to be conspicuous.

In the present invention, a crosslinking aid (g) is further used. As the crosslinking aid (g), a polyfunctional monomer is preferably used, and specific examples thereof include vinyl polyfunctional monomers such as triallyl isocyanurate and divinylbenzene; ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol. Examples thereof include acrylic polyfunctional monomers such as dimethacrylate. The compounding amount of the crosslinking aid (g) is not particularly limited, but generally, the organic peroxide (f)
It is preferably 0.5 to 3.0 parts by mass with respect to 1 part by mass.

In the present invention, an inorganic filler can be blended, if necessary. By compounding the inorganic filler, some physical properties such as compression set of the molded product obtained from the thermoplastic elastomer composition of the present invention are improved, and the cost can be reduced by increasing the amount. Examples of the inorganic filler that can be used include calcium carbonate, talc, magnesium hydroxide, mica, clay, barium sulfate, natural silicic acid, synthetic silicic acid, titanium oxide, carbon black, and the like. Alternatively, two or more kinds can be used. Further, in the present invention,
Reinforcing resin such as poly α-methyl styrene, flame retardant, antioxidant, heat resistance stabilizer, UV absorber, light stabilizer, antistatic agent, release agent, foaming agent, pigment, dye, whitening agent, etc. can do.

The dynamically crosslinked thermoplastic elastomer composition of the present invention is prepared by kneading a mixture containing the above-mentioned components (a) to (g) and optionally other components in a heat-melted state in one step. By doing so, it can be manufactured extremely easily. In addition, as another method, the components (a) to
A method in which a part of (e) is kneaded in the presence of components (f) and (g) in a heated and molten state, and then the remaining parts of components (a) to (e) are added and kneaded, component (a) It is possible to employ a method in which all of (e) to (e) are kneaded in a heat-melted state and then the components (f) and (g) are added and kneaded. A method of kneading in a heating and melting state at once in the step is preferable. Here, the "dynamic crosslinking" in the present specification means the above-mentioned components (a) to (g).
And, optionally, a mixture containing other components is kneaded in a heat-melted state and crosslinked while externally applying a shear stress. The kneading temperature for obtaining the dynamically crosslinked thermoplastic elastomer composition of the present invention is 150 to 250 ° C.
It is preferable to select from the range. In the case of batch production in a single step, the first half of the kneading is performed at a temperature at which the half-life of the organic peroxide (f) is 1/2 or more of the total kneading time, and the second half of the kneading is the half-life of the organic peroxide (f). It is preferable to carry out the kneading at a temperature of less than 1/2 of the total kneading time from the viewpoint that the obtained thermoplastic elastomer composition will have good physical properties and moldability. When the kneading is carried out in the first half of the kneading at a temperature at which the half-life of the organic peroxide (f) is less than 1/2 of the total kneading time, the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b) Further, the crosslinking reaction proceeds before the peroxide crosslinkable olefin resin (d) is finely dispersed in the composition, and the resulting thermoplastic elastomer composition tends to have deteriorated physical properties and moldability, which is not preferable. . In the present specification, the first half of kneading generally means the time from the start of kneading to about half of the total kneading time, and the latter half is the latter half of kneading. Batch kneading in a heated and melted state to obtain the dynamically crosslinked thermoplastic elastomer composition of the present invention may be carried out by any of the methods conventionally used in melt kneading of a thermoplastic polymer,
For example, it can be carried out using a melt kneader such as a single-screw extruder, a twin-screw extruder, a Banbury mixer, a Brabender, a heating roll and various kneaders.

The thermoplastic elastomer composition of the present invention comprises
For example, it can be molded by a conventionally known method such as injection molding, extrusion molding, press molding, calender molding, and hollow molding. From the thermoplastic elastomer composition of the present invention, a molded article excellent in flexibility, mechanical strength and rubber elasticity can be obtained, for example, applications such as sheets, films, plate-like bodies, tubes, hoses and belts; sports. Footwear such as shoes and fashion sandals; Home appliances such as TVs, stereos, vacuum cleaners, refrigerators; Sealing packings for building doors and window frames; Automotive interiors and exteriors such as bumper parts, body panels, weather strips, etc. Parts: It can be effectively used for a wide range of applications such as various grips such as scissors, drivers, toothbrushes, ski poles and pens.

[0046]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. In the following examples, various physical properties (hardness, tensile strength, tensile elongation, compression set, oil resistance and surface condition) of molded articles obtained from the thermoplastic elastomer composition were measured or evaluated by the following methods.

(1) Hardness: "Type A" hardness was measured according to JIS K-6253.

(2) Tensile Strength and Tensile Elongation: Dumbbell No. 5 test pieces were punched out from the injection-molded sheets obtained in the following examples, and a tensile test was carried out according to JIS K-6251. The strength and the elongation were measured and used as the tensile strength and the tensile elongation.

(3) Compression set The injection-molded sheets obtained in the following examples were punched into a circular size having a diameter of 29 mm, six sheets were stacked and pressed at a temperature of 200 ° C. and a pressure of 2.19 MPa to prepare a test piece. Then, using the test piece, in accordance with JIS K-6262, temperature 1
It was compressed at 00 ° C. and 120 ° C. at a compression rate of 25% for 22 hours, and after 22 hours, the compression was released and the compression set at that time was measured.

(4) Oil resistance: length × width × thickness = 40 mm × 20 mm × 2 m from the injection-molded sheets obtained in the following examples
A test piece having a size of m was punched out, and a No. 2 swelling oil was used in accordance with JIS-K6258 to perform an oil resistance test for 24 hours at a temperature of 100 ° C. to obtain a mass increase rate after the oil resistance test with respect to a mass before the oil resistance test. Was taken as the mass swelling rate.

(5) Surface condition of molded product: The surface of the injection-molded sheet obtained in the following example was visually observed to be good (○) when it had a smooth surface without roughness, and The case where the surface was rough was evaluated as defective (x).

The contents and abbreviations of the components used in the following examples are as follows. (1) Hydrogenated block copolymer (a): Blocked by anionic polymerization of a mixed monomer of styrene and isoprene / 1,3-butadiene in cyclohexane using s-butyllithium as a polymerization initiator. The block copolymer obtained by synthesizing the copolymer was subjected to hydrogenation reaction in cyclohexane at 75 ° C. for 5 hours in a hydrogen pressure atmosphere of 0.8 MPa using a Ziegler catalyst, and the following table was used. The hydrogenated block copolymer shown in 1 was obtained.

[0053]

[Table 1]

(2) Non-hydrogenated block copolymer (b): "Clayton D1101" (polystyrene-polybutadiene-polystyrene triblock copolymer; number average molecular weight = 130,000; styrene unit content, manufactured by Kraton Polymer Co., Ltd.) = 31% by mass)

(3) Non-aromatic softening agent for rubber (c): "Diana Process PW-380" manufactured by Idemitsu Kosan Co., Ltd. Paraffin-based process oil kinematic viscosity: 381.6 mm ² / s (40 ° C.), 30. 10m
m ² / s (100 ° C.) Average molecular weight: 746 Ring analysis: CN 27.0%, CP 73.0%

(4) Peroxide cross-linking olefin resin (d): (d) -1: "Novatech H" manufactured by Nippon Polychem Co., Ltd.
J490 "[High-density polyethylene resin; MFR = 20g
/ 10 minutes (190 ° C., 21.2N); density = 0.598
g / cm ³ ] ・ (d) -2: “Novatech L” manufactured by Nippon Polychem Co., Ltd.
J800 "[Low density polyethylene resin; MFR = 20g
/ 10 minutes (190 ° C., 21.2 N); density = 0.918
g / cm ³ ]

(5) Peroxide-decomposing type olefin resin (e): (e) -1: "Grand Polypro J704" manufactured by Grand Polymer Co. [block type polypropylene resin; M
FR = 5 g / 10 minutes (230 ° C., 21.2 N); density =
0.90 g / cm ³ ] (e) -1: "Grand Polypro B701" manufactured by Grand Polymer Co., Ltd. [block type polypropylene resin; M
FR = 0.5 g / 10 minutes (230 ° C., 21.2 N); density = 0.90 g / cm ³ ].

(6) Organic peroxide (f): "Perhexa 25B-40" manufactured by NOF CORPORATION [2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 40% by mass content , Supported material: Silica] (7) Cross-linking aid (g): "Taike M" manufactured by Nippon Kasei Co., Ltd.
-60 "(triallyl isocyanurate, product containing 60% by mass, supported material: diatomaceous earth)

Examples 1 to 6 (1) Hydrogenated block copolymers (a), non-hydrogenated block copolymers (b) of the types shown in Table 2 below, softening agents for non-aromatic rubbers The agent (c), the peroxide cross-linking olefin resin (d), the peroxide decomposing olefin resin (e), the organic peroxide (f) and the cross-linking aid (g) in the amounts shown in Table 2 below. After pre-mixing, it is batch-processed into a twin-screw extruder ("TEM-" manufactured by Toshiba Machine Co., Ltd.).
35B ″), and melt-kneaded at a screw rotation speed of 200 rpm at a temperature shown in Table 2 below, and then extruded in a strand shape and cut to prepare pellets of the dynamically crosslinked thermoplastic elastomer composition. (2) Using the pellets obtained in (1) above, using an injection molding machine (“IS-55EPN” manufactured by Toshiba Machine Co., Ltd .; mold clamping pressure 55 × 10 ³ kg), a melting temperature of 230 ° C.,
Injection molding under the condition of mold temperature of 40 ℃ length × width × thickness =
A sheet-shaped molded product of 110 mm × 110 mm × 2 mm was manufactured. The hardness, tensile strength, tensile elongation, compression set, oil resistance and surface condition of this molded product were measured or evaluated by the methods described above, and the results are shown in Table 2 below.

Comparative Examples 1 to 4 (1) The components shown in Table 3 below were premixed in the amounts shown in Table 3, and the mixture was the same twin-screw extrusion as used in (1) of Example 1. The mixture was supplied to a machine, melt-kneaded at a screw rotation speed of 200 rpm at the temperature shown in Table 3, extruded in a strand shape, and cut into pellets of the dynamically crosslinked thermoplastic elastomer composition. (2) Using the pellets obtained in (1) above, injection molding was performed in the same manner as in (2) of Example 1 to obtain length × width ×
A sheet-like molded product having a thickness of 110 mm × 110 mm × 2 mm was manufactured, and the hardness, tensile strength, tensile elongation, compression set, oil resistance and surface condition of this molded product were measured or evaluated by the above-mentioned methods. , As shown in Table 3 below.

Comparative Examples 5 to 6 (1) The components shown in Table 3 below were premixed in the amounts shown in Table 3, and the mixture was the same twin-screw extrusion as used in (1) of Example 1. The mixture was supplied to a machine, melt-kneaded at a screw rotation speed of 200 rpm at the temperature shown in Table 3, extruded in a strand shape, and cut into pellets of the dynamically crosslinked thermoplastic elastomer composition. (2) Using the pellets obtained in (1) above, injection molding was performed in the same manner as in (2) of Example 1 to obtain length × width ×
A sheet-like molded product having a thickness of 110 mm × 110 mm × 2 mm was manufactured, and the hardness, tensile strength, tensile elongation, compression set, oil resistance and surface condition of this molded product were measured or evaluated by the above-mentioned methods. , As shown in Table 3 below. In Comparative Example 6, the surface of the molded product was remarkably roughened and the quality was poor. Therefore, various physical properties were not measured and evaluated.

[0062]

[Table 2]

[0063]

[Table 3]

As is clear from the results shown in Table 2 above, the thermoplastic elastomer compositions of Examples 1 to 6 were prepared from the hydrogenated block copolymer (a) having a number average molecular weight of 200,000 or more and the non-hydrogenated block copolymer. Polymer (b), softening agent for non-aromatic rubber (c), peroxide cross-linking olefin resin (d) having a density of 0.94 g / cm ³ or more, peroxide decomposing olefin resin (e), organic The peroxide (f) and the crosslinking aid (g) are contained, and the mixing ratio of (a) :( b) is within the range of 85:15 to 99: 1 (mass ratio), and the hydrogenated block co-weight When the compounding amount of the non-aromatic softening agent for rubber (c) is within the range of 50 to 250 parts by mass with respect to 100 parts by mass of the total amount of the combined product (a) and the non-hydrogenated block copolymer (b), the peroxide is The amount of the cross-linked olefin resin (d) is 2.5 to 50 Within parts, 0.5 further amount of peroxide decomposition type olefin resin (e) is the amount of peroxide crosslinking type olefin resin (d)
By being in the range of 10 to 10 times by mass, the thermoplastic elastomer composition can be obtained by the extremely simple operation of melting and kneading all the components in one step under heating. The obtained molded product has excellent flexibility, rubber elasticity, particularly rubber elasticity at high temperature, extremely small compression set, and excellent mechanical strength and oil resistance. No bleed-out and excellent surface characteristics.

On the other hand, as is clear from the results of Table 3, the thermoplastic elastomer composition of Comparative Example 1 was hydrogenated as the hydrogenated block copolymer (a) and had a number average molecular weight of less than 200,000. By using the block copolymer (a) -3, the compression set of the molded product at a high temperature is extremely large, and the rubber elasticity at a high temperature is extremely poor. In addition, in the thermoplastic elastomer composition of Comparative Example 2, since the compounding amount of the non-hydrogenated block copolymer (b) exceeds the compounding amount specified in the present invention, the molded article has a high temperature (1
It remarkably turns yellow at 20 ° C) and is inferior in heat resistance, and further, the degree of swelling with oil is large and the oil resistance is inferior. Comparative Example 3
In the thermoplastic elastomer composition, the blending amount of the non-aromatic rubber softening agent (c) exceeds the blending amount specified in the present invention, so that the bleed-out of the softening agent in the molded article is remarkable. . The thermoplastic elastomer composition of Comparative Example 4 was a peroxide-crosslinked olefin resin (d).
Since it does not contain, it has a large compression set at high temperature and is inferior in rubber elasticity at high temperature.

As is clear from the results in Table 3, the thermoplastic elastomer composition of Comparative Example 5 had a density of 0.9 as the peroxide-crosslinking olefin resin (d).
By using the peroxide-crosslinked olefin resin (d) -2 of less than 4 g / cm ³ , the compression set at high temperature is large, the rubber elasticity at high temperature is poor, and the degree of swelling with oil is high. Largely inferior in oil resistance. In the thermoplastic elastomer composition of Comparative Example 6, the compounded amount of the peroxide-decomposable olefin resin (e) is less than the compounded amount specified in the present invention, so that the surface roughness of the molded product is remarkable.

[0067]

The dynamically crosslinked thermoplastic elastomer composition of the present invention can be produced with high productivity by an extremely simple operation of melting and kneading all the components in one step under heating. The thermoplastic elastomer composition of the present invention and a molded article obtained from the same have excellent flexibility, excellent rubber elasticity, particularly excellent rubber elasticity at high temperatures, and exhibit extremely high compression set even when compressed at high temperatures for a long time. It is small and has excellent characteristics such as high-temperature creep performance, mechanical strength, oil resistance, solvent resistance, heat resistance, and weather resistance, and it has a good appearance without surface roughening or bleed-out of softening agent to the surface. Have. The thermoplastic elastomer composition of the present invention has various properties described above, including industrial products,
It can be effectively used for a wide range of applications.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masanari Uno             36 Towada Stock Exchange, Kamisu Town, Kashima District, Ibaraki Prefecture             Inside the company Kuraray F-term (reference) 4F070 AA08 AB01 AB08 AB16 AC56                       AC66 AC75 AC94 AE02 AE08                       GA05 GB08 GC07                 4J002 AE053 BB004 BB005 BB034                       BB053 BB125 BB145 BB154                       BB164 BP011 BP012 EA047                       EH077 EK016 EK036 EK046                       EK056 EU197 FD023 FD146                       FD157 GC00 GL00 GN00                       GQ00

Claims (3)

[Claims] 1. A hydrogen block copolymer having (i) at least one polymer block A ₁ mainly composed of a vinyl aromatic compound and at least one polymer block B ₁ mainly composed of a conjugated diene compound. Hydrogenated block copolymer (a) having a number average molecular weight of 200,000 or more, at least one polymer block A ₂ mainly composed of a vinyl aromatic compound, and a polymer mainly composed of a conjugated diene compound. Non-hydrogenated non-hydrogenated block copolymer (b) having at least one block B ₂ , softener for non-aromatic rubber (c), peroxide cross-linking type having a density of 0.94 g / cm ³ or more Contains an olefin resin (d), a peroxide-decomposable olefin resin (e), an organic peroxide (f), and a crosslinking aid (g); and
(Ii) The blending ratio of hydrogenated block copolymer (a): non-hydrogenated block copolymer (b) is 85:15 to 99: 1.
(Iii) the total amount of the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b) is 100 mass. 50 to 250 parts by mass relative to 10 parts by mass; (iv) The peroxide cross-linking olefin resin (d) is blended in such an amount that the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b) are mixed. ) Is 2.5 to 50 parts by mass with respect to 100 parts by mass in total; and (v) the peroxide-decomposable olefin-based resin (e) is mixed in the peroxide-crosslinking olefin-based resin (d). 0.5 to 10 times the compounding amount thereof; a thermoplastic elastomer composition obtained by dynamically crosslinking a mixture thereof. 2. A hydrogenated block copolymer (a), a non-hydrogenated block copolymer (b), a non-aromatic softening agent for rubber (c), a peroxide cross-linking olefin resin (d), and a par. A mixture comprising an oxide-decomposable olefinic resin (e), an organic peroxide (f), and a crosslinking aid (g), which are all contained in a single step, is melt-kneaded under heating to be dynamically cross-linked. The thermoplastic elastomer composition according to 1. 3. A hydrogen block copolymer having (i) at least one polymer block A ₁ mainly composed of a vinyl aromatic compound and at least one polymer block B ₁ mainly composed of a conjugated diene compound. A hydrogenated block copolymer (a) having a number average molecular weight of 200,000 or more,
Non-hydrogenated non-hydrogenated block copolymer (b) having at least one polymer block A ₂ mainly composed of a vinyl aromatic compound and at least one polymer block B ₂ mainly composed of a conjugated diene compound (b ), A non-aromatic softener for rubber (c), a peroxide cross-linking olefin resin (d) having a density of 0.94 g / cm ³ or more, a peroxide decomposing olefin resin (e), an organic peroxide ( f) and a crosslinking aid (g); and
(Ii) The blending ratio of hydrogenated block copolymer (a): non-hydrogenated block copolymer (b) is 85:15 to 99: 1.
(Iii) the total amount of the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b) is 100 mass. 50 to 250 parts by mass relative to 10 parts by mass; (iv) The peroxide cross-linking olefin resin (d) is blended in such an amount that the hydrogenated block copolymer (a) and the non-hydrogenated block copolymer (b) are mixed. ) Is 2.5 to 50 parts by mass with respect to 100 parts by mass in total; and (v) the peroxide-decomposable olefin-based resin (e) is mixed in the peroxide-crosslinking olefin-based resin (d). 0.5 to 10 times by mass; a mixture thereof is melt-kneaded under heating in one step to dynamically crosslink, and a method for producing a thermoplastic elastomer composition.