JP2001316539A - Styrenic thermoplastic elastomer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer which has excellent scratch resistance, namely excellent abrasion resistance, further excellent coatability, excellent solvent adhesivity, excellent printability, and so forth. SOLUTION: This styrenic thermoplastic elastomer composition comprising (A) a thermoplastic resin consisting essentially of a polystyrene-based resin, (B) a partially or perfectly crosslinked rubbery polymer comprising an aromatic vinyl/conjugated diene block copolymer and/or a hydrogenated aromatic/ conjugated diene block copolymer and, if necessary, (C) a compatibilizing agent, wherein the components (B) and (C) in the composition are 40 to 90 pts.wt. and <40 pts.wt., respectively, per 100 pts.wt. of [the component (A)+the component (B)+the component (C)].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermoplastic resin containing a polystyrene resin as an essential component, specifically, a polystyrene resin or a mixture of a polystyrene resin and a thermoplastic resin other than a polystyrene resin, preferably Partially or completely crosslinked aromatic vinyl / conjugated diene block copolymer and / or partially or completely hydrogenated aromatic vinyl with a thermoplastic resin comprising a mixture of a polystyrene resin and a polyolefin resin /
The present invention relates to a styrene-based thermoplastic elastomer composition comprising a rubber-like polymer made of a conjugated diene block copolymer and having excellent wear resistance, paintability, solvent adhesion, and printability. The present invention also relates to a styrene-based thermoplastic elastomer composition having excellent adhesion to a polystyrene-based resin such as polystyrene (PS) and high-impact polystyrene (HIPS) and capable of forming a laminate.

[0002]

2. Description of the Related Art As thermoplastic elastomers, diene-based, hydrogenated diene-based, polyolefin-based, PVC-based, polyurethane-based and polyamide-based are known. Among them, the PVC type is not environmentally friendly, the diene type has a problem in weather resistance, and the hydrogenated diene type, the polyurethane type, and the polyamide type have a problem that they are expensive. For this reason, olefin-based thermoplastic elastomers that are environmentally friendly, have relatively excellent weather resistance, and can be supplied at a low price are becoming mainstream. Particularly, it is produced by so-called dynamic crosslinking in which a rubber-like polymer composed of EPDM (ethylene-propylene-diene copolymer) and PP (polypropylene) are cross-linked while being melt-kneaded in an extruder or the like in the presence of a cross-linking agent. Olefin-based thermoplastic elastomers are becoming the center. It is being widely used as a substitute for soft PVC in automobile parts, office equipment, building materials, etc., and is expected to be used in the future.

[0003] This olefin-based thermoplastic elastomer comprises a matrix component composed of PP, which has fluidity for imparting thermoplasticity, and a rubber-like polymer composed of EPDM. At this time, in order to make the olefin-based thermoplastic elastomer rubber-like, the rubber-like polymer is partially or completely cross-linked. The olefin-based thermoplastic elastomer having such a composition has rubber-like properties. However, there is a major problem when attempting to use this olefin-based thermoplastic elastomer widely for applications such as the above-mentioned automotive parts, office equipment, and building materials. That is, soft PVC is
Although it has excellent characteristics such as scratch resistance, easy coating, easy printing, and easy solvent adhesion, this olefin-based thermoplastic elastomer does not satisfy these properties. For this reason, the range of use is currently limited. For that reason,
The development of relatively inexpensive thermoplastic elastomers having excellent scratch resistance, paintability, solvent adhesion, printability, and the like, is expected.

[0004]

SUMMARY OF THE INVENTION In view of the above situation, the present invention provides a thermoplastic elastomer having excellent scratch resistance, that is, excellent abrasion resistance, and also excellent paintability, solvent adhesion, printability, and the like. It is intended to do so.

[0005]

Means for Solving the Problems As a result of studying to achieve the above object, the inventors of the present invention have found that the coexistence of a polystyrene-based resin with an olefin-based thermoplastic elastomer provides abrasion resistance, paintability, and the like. An excellent thermoplastic elastomer can be obtained, that is, the rubber component is generally used in an olefin-based thermoplastic elastomer.
An ethylene / α-olefin copolymer such as DM, partially or completely cross-linking it, and a matrix component for imparting fluidity to a polystyrene resin or a polystyrene resin and another resin, preferably a polyolefin resin. It has been found that by using a thermoplastic resin composed of a mixture of the above, it is possible to obtain a thermoplastic elastomer having excellent abrasion resistance, paintability and the like.

However, when the thermoplastic elastomer is a polystyrene resin,
When the polystyrene-based resin and the ethylene / α-olefin-based copolymer as the rubber component, and the matrix is composed of a mixture of the polystyrene-based resin and the polyolefin-based resin, the polystyrene-based resin and the polyolefin-based resin and the ethylene as the rubber component are used. Affinity with α-olefin copolymer, that is, low strength due to lack of interfacial adhesion between rubber component and matrix due to lack of compatibility, or separation between polystyrene resin and polyolefin resin preferably used, etc. . For that purpose, a compatibilizing agent is required in order to have an affinity between the polystyrene-based resin and the ethylene / α-olefin-based copolymer and the polyolefin-based resin as rubber components.

However, when a compatibilizer is used, the strength is increased, but is not always sufficient. Further, when this thermoplastic elastomer is laminated on a polystyrene-based resin base material such as polystyrene (PS) or high-impact polystyrene (HIPS) and used as a laminate, there arises a problem that it is difficult to recycle. That is, when the laminate is pulverized and reused as a substrate, the strength of the substrate is reduced due to dilution of the compatibilizer. If the compatibilizing agent is added, the strength can be maintained, but there is a problem that the recycling is troublesome and the cost is high.

The inventors of the present invention have made further studies to solve such problems. As a result, the rubbery polymer was converted to a rubber having an affinity for polystyrene resin, that is, the rubbery polymer was replaced with an aromatic vinyl. / Conjugated diene block copolymer and / or partially or completely hydrogenated aromatic vinyl /
The inventors have found that these problems can be solved by using a rubber made of a conjugated diene block copolymer, and have completed the present invention (here, and / or the meaning of
The rubbery polymer may be an aromatic vinyl / conjugated diene block copolymer alone or a partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer. Or a mixture of an aromatic vinyl / conjugated diene block copolymer and a partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer.) Further, it was found that a resin other than a polystyrene resin and a polyolefin resin, such as a polyphenylene ether resin compatible with polystyrene, can be used as a thermoplastic elastomer excellent in heat resistance and the like to complete the present invention. Reached.

That is, the present invention basically comprises (A) a thermoplastic resin containing a polystyrene resin as an essential component; and (B) an aromatic vinyl / conjugated diene block copolymer and / or a hydrogenated aromatic vinyl / conjugate. The present invention relates to a styrenic thermoplastic elastomer composition comprising a diene block copolymer and a partially or completely crosslinked rubbery polymer.

The present invention generally does not require a compatibilizer. For example, when the amount of aromatic vinyl in the aromatic vinyl / conjugated diene block copolymer is small, the strength may not be sufficient. In this case, a compatibilizer may be added as needed. Accordingly, the present invention comprises (A) a thermoplastic resin containing a polystyrene resin as an essential component, and (B) an aromatic vinyl / conjugated diene block copolymer and / or a hydrogenated aromatic vinyl / conjugated diene block copolymer. The present invention also relates to a styrenic thermoplastic elastomer composition comprising a partially or completely crosslinked rubbery polymer and, if necessary, (C) a compatibilizer. In this composition, the component amounts are as follows, when the components (A) + (B) + (C) are 100 parts by weight.
Component (B) in the composition is from 40 to 90 parts by weight and component (C) is less than 40 parts by weight.

Hereinafter, the present invention will be described in detail. First, each component of the present invention will be described in detail. The polystyrene resin which is an essential component of the thermoplastic resin which is the component (A) in the styrene thermoplastic elastomer composition of the present invention is basically a styrene monomer polymer, that is, polystyrene or styrene monomer. It is a copolymer of a monomer and another monomer. Examples of the copolymerizable monomer include styrene-based monomers such as α-methylstyrene, p-chlorostyrene, p-bromostyrene, and 2,4,5-tribromostyrene, and acrylonitrile and methacrylonitrile. Unsaturated nitrile monomers, acrylate monomers such as methyl acrylate and butyl acrylate, methacrylate monomers such as methyl methacrylate and ethyl methacrylate, and acids such as maleic anhydride and itaconic anhydride Examples thereof include anhydride monomers, maleimide monomers such as maleimide, N-methylmaleimide and N-phenylmaleimide, and organic acid monomers such as acrylic acid and methacrylic acid. Of these, polystyrene is inexpensive and most preferred. Further, a polystyrene-based resin comprising a copolymer of a styrene monomer, an acrylate monomer and a methacrylate monomer is obtained from a styrene-based thermoplastic elastomer composition containing this as the component (A). It is preferable because the molded article has excellent weather resistance.

The melt flow rate (MFR) of the polystyrene resin used is preferably in the range of 0.1 to 50 g / 10 min (measured at 200 ° C. under a load of 5 kg). Further, the range is more preferably 0.5 to 30 g / 10 minutes. If it is less than 0.1 g / 10 minutes, the fluidity of the obtained styrene-based thermoplastic elastomer composition is low. On the other hand, if it exceeds 50 g / 10 minutes, the mechanical strength of a molded article molded from the obtained styrene-based thermoplastic elastomer composition is low.

The thermoplastic resin as the component (A) is preferably a polystyrene resin as a main component. The thermoplastic resin is made of a polystyrene resin or a mixture of a polystyrene resin and another resin, preferably a polyolefin resin. At this time, the polystyrene resin is
Preferably 40% by weight or more, more preferably 50% by weight
That is all. The reason why the polystyrene-based resin is used as the main component is that, for example, when the thermoplastic resin as the component (A) is composed of a polystyrene-based resin and a polyolefin-based resin and the polyolefin-based resin is the main component, the paintability, the solvent adhesion, the printing, and the like. It is inferior in properties and cannot be used for applications requiring these characteristics, for example, toys for replacement of soft PVC, construction materials such as waterproof sheets, and the like. However, by using a polystyrene-based resin as a main component, it can be expanded to these uses.

The thermoplastic resin as the component (A) in the styrenic thermoplastic elastomer of the present invention comprises a polystyrene resin or a mixture of a polystyrene resin and another resin, preferably a polyolefin resin. The polyolefin resin used can be roughly classified into a polyethylene resin, a polypropylene resin or a mixture of a polyethylene resin and a polypropylene resin.

As the polyethylene resin, high density polyethylene (HDPE), low density polyethylene (LDP)
E), linear low density polyethylene (LLDPE), copolymer of acrylic vinyl monomer and ethylene (EE
A, EMMA, etc.) or a copolymer of a vinyl acetate monomer and ethylene (EVA). However, among these, high density polyethylene (HD
PE), low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE) are particularly preferred because they are available at low cost. These polyethylene resins may be used alone or in combination of two or more.

When high density polyethylene (HDPE) is used, its density generally ranges from 0.930 to 0.970.
g / cm ² and the melt flow rate (MF
R) is 0.05 to 100 g / 10 min (190 ° C, 2.
(Measured under a load of 16 kg). When low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE) is used, its density is generally in the range of 0.900 to 0.930 g / cm ² and the melt flow rate (MFR) is 0.05 ~
It is preferably in the range of 100 g / 10 minutes (measured at 190 ° C. under a load of 2.16 kg). When the melt flow rate exceeds 100 g / 10 minutes, the mechanical strength and heat resistance of the molded article obtained from the styrene-based thermoplastic elastomer composition of the present invention are insufficient, and when it is less than 0.05 g / 10 minutes. When molding the styrenic thermoplastic elastomer composition of the present invention, the fluidity is poor and the molding processability is undesirably reduced.

Examples of the polypropylene resin include homopolypropylene, copolymer resins (including block and random) of propylene with other α-olefins such as ethylene, butene-1, pentene-1, and hexene-1. be able to. The melt flow rate (MFR) of the polypropylene resin is 0.1 to 100 g / 10 min (230
C., measured under a load of 2.16 kg). If the melt flow rate exceeds 100 g / 10 minutes, the mechanical strength and heat resistance of the molded article obtained from the styrene-based thermoplastic elastomer composition of the present invention are insufficient, and if it is less than 0.1 g / 10 minutes. When molding the styrenic thermoplastic elastomer composition of the present invention, the fluidity is poor and the molding processability is undesirably reduced.

The polyolefin resin used in combination with the polystyrene resin as the component (A) in the styrenic thermoplastic elastomer composition of the present invention comprises a polyethylene resin and / or a polypropylene resin as described above. Polypropylene resins are more preferable because of their high heat resistance. However, homopolypropylene generally tends to be oxidatively decomposed and has a tendency to decrease in mechanical strength due to a decrease in molecular weight during long-term use. On the other hand, polyethylene resins generally have a tendency to crosslink without being oxidatively decomposed and maintain or improve mechanical strength. For this reason, when using a polypropylene-based resin, particularly when used for applications requiring durability, use a homopolypropylene and a polyethylene-based resin together or use a propylene-ethylene-based random or block polymer. Is preferred. In any case, the polypropylene resin has higher heat resistance than the polyethylene resin, and the polyolefin resin is most preferably a polypropylene resin.

The amount of the polystyrene resin in the thermoplastic resin (A) is preferably 40 to 100% by weight. More preferably, it is 50 to 100% by weight. When the amount is less than 40% by weight, when the resin other than the polystyrene-based resin is a polyolefin-based resin, the paintability, solvent adhesion, and printability are poor. When the resin other than the polystyrene resin is not a polyolefin resin, the advantage of using an inexpensive polystyrene resin as a main component is diminished.

Next, the partially or completely crosslinked rubbery polymer as the component (B) will be described. The rubbery polymer is composed of a block copolymer composed of an aromatic vinyl unit and a conjugated diene unit. The block copolymer also includes a partially or completely hydrogenated double bond of a conjugated diene component. This aromatic vinyl / conjugated diene block copolymer comprises at least one polymer block (S) mainly composed of an aromatic vinyl compound and at least one polymer block (B) mainly composed of a conjugated diene. It is a block copolymer whose structure is, for example, SB, S-
BS, BSBS, (SB-) nSi and the like. Examples of the conjugated diene include butadiene and isoprene. The rubbery polymer of the present invention includes a partially or completely hydrogenated double bond of a conjugated diene component, but a hydrogenated aromatic vinyl / conjugated diene block copolymer and a non-hydrogenated aromatic vinyl When comparing the / conjugated block diene copolymer, the hydrogenated aromatic vinyl / conjugated diene block copolymer is more excellent in weather resistance, heat resistance and the like, and is more preferable.

The amount of aromatic vinyl in the aromatic vinyl / conjugated diene random copolymer, which is the rubbery polymer as the component (B) of the composition of the present invention, is preferably 1 to 70% by weight, more preferably 5 to 70% by weight. 60% by weight, even more preferably 10-5%
0% by weight. When the amount is less than 1% by weight, the strength of a molded article obtained by molding the polystyrene-based thermoplastic elastomer composition of the present invention using the rubbery polymer as the component (B) is low. The reason for this is that when the compatibilizer as the component (C) is not used, the compatibility between the rubber component and the polystyrene-based resin as the matrix is low, and thus the interface strength is low. Even if a compatibilizer is used, it is difficult to provide sufficient interfacial strength. If it exceeds 70% by weight, the rubber-like properties deteriorate and the performance as an elastomer is low.

The conjugated diene in the aromatic vinyl / conjugated diene block copolymer has 1,2 and 1,4 bonds. By having both the 1,2 bond and the 1,4 bond in the molecule, the rubber elasticity is high, the glass transition temperature (Tg) is lowered, and the low temperature characteristics are improved. The 1,2 bond amount of the conjugated diene, that is, the 1,2 vinyl bond amount is preferably 5 to 95%.
More preferably, it is 10 to 90%. When the amount of 1,2-vinyl bond is 5% or less and 95% or more, rubber elasticity and low-temperature characteristics are also not preferable.

The melt flow rate (MFR) of the rubbery polymer which is the component (B) of the composition of the present invention is a hydrogenated aromatic vinyl / conjugated diene block copolymer particularly preferably used for the rubbery polymer. In this case, the melt flow rate (MFR) is 0.01 to 20 g / 10 min (19
(Measured under a load of 0 ° C. and a load of 2.16 kg) are preferably used. More preferably, 0.1 to 10 g / 1.
0 minutes. When the melt flow rate exceeds 20 g / 10 minutes, a thermoplastic elastomer having low mechanical strength is obtained.
On the other hand, if it is less than 0.01 / 10 minutes, the fluidity is poor when producing the styrene-based thermoplastic elastomer of the present invention,
It is not preferable because the processability decreases.

The rubbery polymer as the component (B) of the composition of the present invention may be used as a mixture of a plurality of types. For example, a combination of a non-hydrogenated aromatic vinyl / conjugated diene block copolymer and a hydrogenated aromatic vinyl / conjugated diene block copolymer, or an aromatic vinyl / conjugate having different aromatic vinyl content or 1,2-vinyl content Diene block copolymer or aromatic vinyl content or 1,
2 There is a hydrogenated aromatic vinyl / conjugated diene block copolymer having a different vinyl content. In such a case, it is possible to further improve the processability, the elastomer properties, and the like.

Further, the rubbery polymer as the component (B) of the composition of the present invention is basically composed of the above-mentioned aromatic vinyl / conjugated diene block copolymer and / or hydrogenated aromatic vinyl / conjugated diene. Although it is a block copolymer, other rubbery polymers such as an aromatic vinyl / conjugated diene random copolymer, a hydrogenated aromatic vinyl / conjugated diene random copolymer or ethylene / α-
It is also possible to use an olefin-based copolymer (such as EPDM) in combination.

The rubbery polymer as the component (B) of the composition of the present invention must be partially or completely crosslinked. Molded articles obtained from the styrene-based thermoplastic elastomer composition of the present invention are those having high rubber elasticity with greatly improved heat resistance, compression set, rebound resilience, etc. become. When the ratio of the crosslinked rubbery polymer (the rubbery polymer that does not dissolve in the solvent) in the total rubbery polymer in the styrene-based thermoplastic elastomer composition of the present invention is defined by the degree of crosslinking, the degree of crosslinking is as follows: It is preferably at least 30%, more preferably at least 50%.

It should be noted that JP-A-11-293046 and JP-A-11-293072 disclose that an aromatic vinyl-olefin random copolymer is a rubber-like polymer and that a fluid component is a styrene resin and a crystalline olefin resin. A dynamically crosslinked thermoplastic elastomer made of a resin or a styrene resin is disclosed. The rubbery polymer of the styrenic thermoplastic elastomer of the present invention comprises an aromatic vinyl / conjugated diene block copolymer or a partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer. A comparison between the case where the rubber-like polymer of the above-mentioned publication is used and the case where the rubber-like polymer composed of the aromatic vinyl-olefin random copolymer of the publication is used shows that the performance as an elastomer, that is, the rubber elasticity of aromatic vinyl / Conjugated diene block copolymers or partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymers are much better. The reason is as follows.

That is, the styrene content in the styrene-ethylene random copolymer used in the publication is 11.5 to 37.1 mol% (32.6 to 37.1 mol%) in order to make it rubber-like.
68.7% by weight). The glass transition temperature (Tg) of the styrene-ethylene random copolymer in this range is near room temperature, and the rubber elasticity at low temperatures is poor. On the other hand, the rubbery polymer as the component (B) of the composition of the present invention is the same styrene-based copolymer, but uses a conjugated diene. Further, the conjugated diene can be copolymerized by arbitrarily controlling 1,2 bonds and 1,4 bonds. 1,2
The glass transition temperature (Tg) is-
The temperature can be lowered to 50 ° C. or lower, and the styrene-based thermoplastic elastomer using the rubber-like polymer of the present invention can be a thermoplastic elastomer having excellent low-temperature properties.

Next, the compatibilizer, which is the component (C) added as needed in the styrene-based thermoplastic elastomer composition of the present invention, will be described. The function of compatibilizing the polystyrene resin as the component (A) with the conjugated diene component or the hydrogenated conjugated diene component in the aromatic vinyl / conjugated diene block copolymer as the rubbery polymer as the component (B). When the compatibilizer or the component (A) is a mixture of a polystyrene resin and a polyolefin resin, a compatibilizer having a function of compatibilizing the polystyrene resin and the polyolefin resin is used as necessary.

Examples of the compatibilizer as the component (C) include those having both a polystyrene component and a polyolefin component in the molecule. For example, A is polystyrene or a copolymer of polystyrene, preferably polystyrene, B is polyethylene, polypropylene, an ethylene / α-olefin copolymer containing ethylene and an α-olefin having 3 to 20 carbon atoms, and hydrogenated polybutadiene. Block copolymer, hydrogenated polyisoprene, etc., A-grafted B copolymer and B-grafted A
Copolymers and the like can be mentioned. Further, a copolymer in which A is randomly introduced into the B polymer component, specifically, for example, an A monomer component in a B polymer component made of polyethylene, such as an ethylene-styrene random polymer described below, That is, a copolymer in which a styrene monomer is randomly introduced can be used. Here, B may be a single one or a combination of two or more.

Specific examples thereof include polystyrene-grafted polypropylene, polystyrene-grafted polyethylene, an ethylene / styrene random copolymer and the component (B) of the composition of the present invention, but aromatic vinyl / conjugated diene having a different composition. Block copolymers or hydrogenated aromatic vinyl / conjugated diene block copolymers, and also aromatic vinyl / conjugated diene random copolymers or hydrogenated aromatic vinyl / conjugated diene random copolymers can be used. In order for the aromatic vinyl / conjugated diene block copolymer or the hydrogenated aromatic vinyl / conjugated diene block copolymer to exhibit the function as a compatibilizer, it is necessary that the copolymer is not crosslinked.

When the compatibilizer which is the component (C) in the styrenic thermoplastic resin composition of the present invention is used, it may be used alone or in combination of two or more. The styrenic thermoplastic elastomer composition of the present invention comprises a polystyrene resin as the component (A) or a mixture of the polystyrene resin and another resin, preferably a polyolefin resin, and a partially or completely crosslinked component (B). Rubber / vinyl / conjugated diene block copolymer or partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer and, if necessary, compatibilizing component (C) Agent,
The total amount of the components (A), (B) and (C) is 100
In terms of parts by weight, the component (B) is 40 to 90 parts by weight, preferably 45 to 80 parts by weight, and more preferably 50 to 70 parts by weight.
Parts by weight.

The component (C) comprises the components (A) and (B)
When the total amount of the component and the component (C) is 100 parts by weight, 4
It is less than 0 parts by weight, preferably less than 20 parts by weight, more preferably less than 10 parts by weight, particularly preferably zero. (B)
When the amount of the component is less than 40 parts by weight, the composition of the present invention lacks rubber elasticity and the performance as an elastomer is inferior. When the amount exceeds 90 parts by weight, the amount of the thermoplastic resin which imparts fluidity, which is the component (A), becomes small, and the fluidity of the composition becomes poor, making molding difficult. When the amount of the component (C) exceeds 40 parts by weight, the rubber elasticity is reduced depending on the type of the compatibilizer, and at the same time, the compatibilizer is generally expensive, so that the economic efficiency is low.

The thermoplastic resin which is the component (A) of the styrenic thermoplastic elastomer of the present invention is basically a polystyrene resin or a polystyrene resin and another resin.
It is preferably made of a mixture with a polyolefin-based resin, but as the thermoplastic resin used in combination with the polystyrene-based resin, in addition to the polyolefin-based resin, for example, polyphenylene ether-based, polyvinyl chloride-based, polyamide-based, polyester-based, and polyphenylene sulfide-based And thermoplastic resins such as polycarbonate, polymethacrylate and the like. Among them, polyphenylene ether-based resins are most preferred because they have good compatibility with polystyrene-based resins. When other thermoplastic resin is used in combination, this resin and polystyrene resin and aromatic vinyl /
It is preferable to add a new compatibilizer that is compatible with the conjugated diene block copolymer or the partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer.

Various additives can be added to the styrenic thermoplastic elastomer composition of the present invention. Examples of this include softeners, glass fibers, organic or inorganic fibers such as polyacrylonitrile fibers or carbon fibers,
Metal fibers such as copper or brass, whiskers such as potassium titanate, magnesium oxysulfate, aluminum borate, calcium carbonate, magnesium carbonate, silica, carbon black, titanium oxide, clay, mica,
Powdered inorganic fillers such as talc, magnesium hydroxide and aluminum hydroxide, plasticizers such as polyethylene glycol and dioctyl phthalate (DOP), organic and inorganic pigments, heat stabilizers, antioxidants, ultraviolet absorbers, and light Stabilizer, flame retardant, silicone oil, anti-blocking agent,
Foaming agents, antistatic agents, antibacterial agents and the like can be mentioned.

Among these, the softener has an effect of lowering the hardness of a molded product obtained by molding the styrene thermoplastic elastomer of the present invention, and is a very effective component.
As the softener, a process oil such as a paraffinic or naphthenic oil is particularly preferable. When these softeners are added, the compounding amount thereof is 0.5 to 200 parts by weight, preferably 1 to 100 parts by weight, more preferably 1 to 50 parts by weight, particularly preferably 100 to 100 parts by weight of the composition of the present invention. Preferably, 1 to 30 parts by weight is used. If it is less than 0.5 part by weight, the effect of adding the softener is low. If the amount exceeds 200 parts by weight, bleed out of the softener becomes remarkable, which is not preferable.

Next, a method for producing the styrenic thermoplastic elastomer composition of the present invention will be described. The polystyrene-based thermoplastic elastomer composition of the present invention is not limited to this method, but can be produced, for example, by the following method. The first method is a mixture of a polystyrene resin as the component (A) or a mixture of a polystyrene resin and a thermoplastic resin other than the polystyrene resin, preferably a mixture of a polystyrene resin and a polyolefin resin,
The aromatic vinyl / conjugated diene block copolymer or the partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer which is a raw material of the component (B), ) A method in which a crosslinking agent comprising a compatibilizing agent, a radical initiator, a crosslinking aid, and the like, which are components, is heat-treated with a twin-screw extruder, a Banbury mixer, or the like to partially or completely dynamically crosslink the rubber-like polymer. In addition,
When a compatibilizer is used, when the compatibilizer is crosslinked with a radical initiator or a crosslinking aid, the compatibilizer is crosslinked without adding the compatibilizer, and the compatibilizer is added after the rubbery polymer is crosslinked. Alternatively, the styrene-based thermoplastic elastomer composition of the present invention is obtained by, for example, a method of melt-kneading the obtained thermoplastic elastomer and a compatibilizer with a twin-screw extruder, a Banbury mixer, or the like.

The second method is that, when the thermoplastic resin of the component (A) is a mixture of a polystyrene resin and a polyolefin resin, the polyolefin resin and the aromatic vinyl / conjugated raw material of the component (B) are used. A rubbery polymer composed of a diene block copolymer or a partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer, a crosslinking agent and a crosslinking aid are heat-treated with a twin-screw extruder, a Banbury mixer, etc. The polymer is partially or completely cross-linked in the presence of a cross-linking agent comprising a radical initiator, a cross-linking aid, etc., and the resulting dynamically cross-linked olefin-based thermoplastic elastomer (hereinafter referred to as polyolefin-based resin and aromatic vinyl / conjugated diene block) Copolymer or a rubbery polymer consisting of partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer Bridges agent presence partially or completely crosslinked elastomeric referred olefin matrix thermoplastic elastomer) and a polystyrene resin twin-screw extruder, a method of melt-kneading in a Banbury mixer or the like.

When a compatibilizing agent is added, the compatibilizing agent may be polyolefin-based at the time of production of the olefin matrix thermoplastic elastomer as long as the compatibilizing agent does not cause a crosslinking reaction by a radical initiator and a crosslinking aid. The resin and the rubber-like polymer may be coexisted, but generally, when the olefin matrix thermoplastic elastomer and the polystyrene resin are melt-kneaded, including those that do not cause a cross-linking reaction and those that cause a cross-linking reaction. Is preferred.

The polyolefin resin used for producing the olefin matrix thermoplastic elastomer is as follows:
When a polyethylene-based resin alone is used, the olefin matrix thermoplastic elastomer obtained by crosslinking the matrix may not show thermoplasticity. Therefore, it is preferable that the polyolefin-based resin is mainly composed of a non-crosslinked polypropylene-based resin or a mixture of a polypropylene-based resin and a polyethylene-based resin.

The third method includes a method of impregnating the olefin matrix thermoplastic elastomer obtained by the second method with a styrene monomer and polymerizing styrene in the presence of a radical initiator. In the third method, the compatibilizer is
When a compatibilizer that is not crosslinked by a radical initiator or a crosslinking aid is used, it may be added at the time of production of the olefin matrix thermoplastic elastomer, or after the styrene is polymerized, the compatibilizer is added and melt-kneaded. Then, the composition of the present invention may be used. Among these methods, the first method is most preferable because the styrene-based thermoplastic elastomer composition of the present invention can be produced in one step.

In the case of producing by the above-mentioned production method, examples of the radical initiator or the polymerization initiator which is a crosslinking agent include a radical initiator such as an organic peroxide and an organic azo compound. As a specific example, 1,1-bis (t
-Butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy)-
3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-
Bis (t-butylperoxy) cyclododecane, 1,1
-Bis (t-butylperoxy) cyclohexane, 2,
2-bis (t-butylperoxy) octane, n-butyl-4,4-bis (t-butylperoxy) butane, n
Peroxy ketals such as -butyl-4,4-bis (t-butylperoxy) valerate; di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, α, α'-bis ( t-butylperoxy-m-isopropyl) benzene, α, α′-bis (t-butylperoxy) diisopropylbenzene,
Dialkyl peroxides such as 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane and 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3; Oxide, isobutyryl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide,
3,5,5-trimethylhexanoyl peroxide,
Diacyl peroxides such as benzoyl peroxide, 2,4-dichlorobenzoyl peroxide and m-trioyl peroxide; t-butylperoxyacetate, t-butylperoxyisobutyrate, t
-Butylperoxy-2-ethylhexanoate, t-
Butylperoxylaurate, t-butylperoxybenzoate, di-t-butylperoxyisophthalate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxymaleic acid, t-butylperoxymaleate
-Peroxyesters such as butylperoxyisopropyl carbonate and cumylperoxyoctate; and t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-
2,5-dihydroperoxide and 1,1,3,
Hydroperoxides such as 3-tetramethylbutyl peroxide can be exemplified.

Among these compounds, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, 2,5-dimethyl -2,5-bis (t-butylperoxy) hexane and 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3 are preferred. When crosslinking the rubbery polymer by the first or second method, these radical initiators,
0.02 to 3 parts by weight per 100 parts by weight of the rubbery polymer,
Preferably it is used in an amount of 0.05 to 1 part by weight. The level of crosslinking is mainly determined by this amount. If the amount is less than 0.02 parts by weight, the crosslinking is insufficient, and if the amount exceeds 3 parts by weight, the crosslinking rate is not greatly improved, so that it is not a preferable direction.

As a crosslinking aid, divinylbenzene, triallyl isocyanurate, triallyl cyanurate,
Diacetone diacrylamide, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate,
Trimethylolpropane triacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diisopropenylbenzene, P-quinone dioxime, P, P'-dibenzoylquinone dioxime, phenylmaleimide, allyl methacrylate, N , N'-m-
Phenylene bismaleimide, diallyl phthalate, tetraallyloxyethane, 1,2-polybutadiene and the like are preferably used. These crosslinking aids may be used in combination of two or more.

The crosslinking aid is used in an amount of 0.1 to 5 parts by weight, preferably 0.5 to 2 parts by weight, based on 100 parts by weight of the rubbery polymer. If the amount is less than 0.1 part by weight, the crosslinking rate is low, which is not preferable. If the amount exceeds 5 parts by weight, the crosslinking rate is not greatly improved, and an excessive amount of the crosslinking aid remains, which is not a preferable direction. As a method for crosslinking, it is preferable to use a radical initiator and a crosslinking aid as described above, but in addition, a phenol resin or bismaleimide may be used as a crosslinking agent.

The aromatic vinyl / conjugated diene block copolymer which is the component (B) of the composition of the present invention or the rubbery polymer composed of partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer is used. As a device for partially or completely crosslinking, a Banbury mixer, a kneader, a single screw extruder, a twin screw extruder, or the like can be used. In order to achieve particularly efficient crosslinking, a twin-screw extruder is preferably used. The twin-screw extruder disperses the rubbery polymer and the thermoplastic resin uniformly and finely, and can preferably carry out a crosslinking reaction with a crosslinking agent, and is suitable for continuously producing a crosslinked product.

More specifically, the most preferable manufacturing method can be manufactured through the following processing steps. That is, a rubber-like polymer composed of an aromatic vinyl / conjugated diene block copolymer or a partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer and a polystyrene resin, or a polystyrene resin and a polystyrene resin. Of a thermoplastic resin, preferably a polyolefin-based resin, into a hopper of an extruder.

Crosslinking agents such as a radical initiator and a crosslinking aid include
The rubbery polymer and the thermoplastic resin may be added together with the thermoplastic resin from the beginning, or may be added in the middle of the extruder.
When oil is added as a softener, it may be added from the middle of the extruder, or may be added separately at the beginning and during the middle. A part of the rubbery polymer and the thermoplastic resin may be added in the middle of the extruder. When heated and melted in an extruder and kneaded, the rubber-like polymer reacts with a radical initiator and a crosslinking aid, and further, if necessary, an oil or the like is added and melt-kneaded to perform a crosslinking reaction and kneading dispersion. And after taking out from the extruder. By pelletizing, pellets of the styrenic thermoplastic elastomer composition of the present invention can be obtained.

The styrenic thermoplastic elastomer composition of the present invention thus obtained can be used to produce various molded articles by any molding method. As the molding method, injection molding, extrusion molding, compression molding, blow molding, calender molding, foam molding and the like are preferably used. The styrene-based thermoplastic elastomer composition of the present invention has excellent abrasion resistance. In addition, it becomes a thermoplastic elastomer with excellent paintability, solvent adhesion, printability, etc., various automotive parts, office equipment,
It can be widely used for building materials and toys.

Further, the styrenic thermoplastic elastomer composition of the present invention generally comprises an aromatic vinyl / conjugated diene block copolymer or a partially or completely hydrogenated aromatic vinyl / conjugated diene block copolymer. It is composed of a matrix mainly composed of 0.2 to 2 μm crosslinked rubbery polymer particles and a polystyrene resin. Therefore, it can be melt-bonded to a styrene-based resin such as polystyrene (PS) or high-impact polystyrene (HIPS). The base material is made of polystyrene (PS) or high-impact polystyrene (HIPS), and the skin material of the present invention is used. Laminated products made of a styrene-based thermoplastic elastomer composition,
That is, a high-strength material having a softened surface can be obtained. This laminate is used for building material applications, such as stair railings,
It can also be used for non-slip mats and deck boards in bathrooms.

[0051]

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In these examples and comparative examples, the test methods used for evaluating various physical properties, and the production methods of the thermoplastic elastomer used for the raw materials and the blending are as follows. 1. Test Method (1) Hardness Four sheets having a thickness of 2 mm were piled up and evaluated according to ASTM D2240 using an A type in an atmosphere of 23 ° C.

(2) Tensile breaking strength [kgf / cm2] The tensile breaking strength was evaluated at 23 ° C according to JIS K6251. (3) Tensile elongation at break [%] Evaluated at 23 ° C. according to JIS K6251. (4) Compression set (C-set) [%] Evaluated at 70 ° C. for 22 hours according to JIS K6301.

(5) Wear Resistance Evaluation was performed using a Gakushin type wear tester. The evaluation conditions are as follows. Temperature condition: 23 ° C atmosphere Stroke: 120 mm Frequency: 1 reciprocation / 2 seconds Load: 500 g Wearing material: 100% cotton cloth Kanakin No. 3 (JIS L0)
Contact area: 1 cm ^{2 The} evaluation result is represented by the abrasion loss (g) during 2000 reciprocations.

(6) Adhesion The styrene-based thermoplastic elastomer of the present invention was press-molded to obtain a sheet having a thickness of 0.2 mm. This sheet was attached to a mold of an injection molding machine (Toshiba IS45PNV), and a commercially available impact-resistant polystyrene (HIPS) was injection-molded to a thickness of 2 mm. The adhesiveness between the styrene-based thermoplastic elastomer and HIPS of the obtained laminate was evaluated. The criteria are as follows. ◎ Does not peel off at all (substrate is broken) ○ Peels off when peeled off with strong force △ Can be peeled off relatively easily, although not adhered × Not adhered at all

(7) Coatability A commercially available urethane paint (solvent type) was brush-coated on the styrene-based thermoplastic elastomer sheet of the present invention and dried. When the elastomer was bent, it was evaluated whether it was peeled off from the substrate. The criteria are as follows.

○ No peeling Δ No peeling. However, if it bends many times, it peels partially × peels

(8) Degree of Crosslinking 0.5 g of the crosslinked thermoplastic elastomer was added to xylene 200
Reflux in ml for 4 hours. The solution was filtered with a filter paper for quantification, the residue on the filter paper was vacuum-dried, quantified, and calculated as the ratio (%) of the weight of the residue to the weight of the rubbery polymer in the crosslinked thermoplastic elastomer.

(9) Measurement of hydrogenation rate The aromatic vinyl / butadiene block copolymer before hydrogenation was dissolved in deuterated chloroform, and the FT-NMR (270 mega, manufactured by JEOL Ltd.) had a chemical shift of 4.7 to 4.7. 5.2 ppm
Integrated intensity of proton (= CH-) by 1,2-vinyl of (signal C ₀ ) and vinyl proton (= CH _2- ) of chemical shift 5.2 to 5.8 ppm (signal D ₀ ) (V) was calculated from the following equation. (V) = [0.5C ₀ /〔0.5C ₀ +0.5 (D ₀ -0.5C _0)]] × 100 Next, the hydrogenated vinyl aromatic / butadiene block copolymer was dissolved in heavy chloroform, similar methyl proton due hydrogenated 1,2-bond chemical shift 0.6～1.0Ppm (the signal a ₁₎ at FT-NMR in (-CH ₃₎ chemical shifts 4.7～5.2Ppm ( signal C ₁ to) not hydrogenated 1,2-vinyl by proton (= CH-), chemical shifts from 5.2 to 5.
8 ppm (the signal D ₀₁₎ of the hydrogenated non-vinyl proton (= CH ₂ -) 1,2 than integrated intensity of
-The hydrogenation rate (B) of the vinyl bond portion and the hydrogenation rate (C) of 1,4-vinyl were calculated, and the overall hydrogenation rate (A) was calculated. _{(B) = [(A 11} /3) / _{[(A 11/3) + (} C 11/2) ]] × 100 (C) = _{[[0.5 (D 0 -0.5C 0) -0.5} (D 11 −0.5C ₁₁ )] / 0.5 (D
₀ −0.5C ₀ )] × 100 where A ₁₁ = pA ₁ , C ₁₁ = pC ₁ , D ₁₁ = pD ₁ , p = 0.5C ₀ /(0.5
And _{C 1 + A 1/3)} .

(10) 1,2-vinyl bond amount (before hydrogenation) Calculated as (V) × (B) / 100.

2. Raw Materials (1) Rubbery polymer (a) Styrene-butadiene block copolymer The styrene-butadiene block copolymer and hydrogenated styrene-butadiene block copolymer shown in Table 1 were produced. The polymerization was carried out by a known method. (Referred to as SBR) Table 1 shows the compositions and hydrogenation rates of the manufactured SBRs 1 to 6. (b) Styrene-isoprene block copolymer Hydrogenated styrene-isoprene block copolymer Septon (trade name: 2023, styrene content: 13; manufactured by Kuraray Co., Ltd.)
%) (Referred to as SIR) (c) Ethylene-styrene random copolymer Produced by the method described in JP-A-7-70223. The ethylene / styrene composition ratio of the copolymer is 30 /
70 (weight ratio) (referred to as ESP)

(2) Polystyrene resin (a) Polystyrene manufactured by Asahi Kasei Corporation (trade name: GP
685) (referred to as PS) (b) Prototype of Asahi Kasei Kogyo Co., Ltd. Styrene / methyl methacrylate copolymer (methyl methacrylate 20% by weight)
(C) Prototype of Asahi Kasei Kogyo Co., Ltd. Styrene / n-butyl acrylate copolymer (n-butyl acrylate 5% by weight) (referred to as BS)

(3) Olefin-based resin polypropylene Isotactic homopolypropylene (trade name: PM900A) (referred to as PP) manufactured by Japan Polyolefin Co., Ltd. (4) Polyphenylene ether-based resin Polyphenylene ether powder manufactured by Asahi Kasei Kogyo Co., Ltd. ηsp / C = 0.5 (chloroform) (referred to as PPE)

(5) Radical initiator 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane (trade name: Perhexa 25B) manufactured by NOF Corporation (referred to as POX) ) Cross-linking aid Triallyl isocyanurate (TA) manufactured by Nippon Kasei Co., Ltd.
(7) Softener (paraffin oil) Diana Process Oil (trade name: manufactured by Idemitsu Kosan Co., Ltd.)
(PW-380) (8) Compatibilizer Hydrogenated styrene-butadiene block copolymer, manufactured by Asahi Kasei Kogyo Co., Ltd., Tuftec (styrene content: 60)
%) (Referred to as HTR)

3. Production of olefin matrix thermoplastic elastomer As an extruder, a twin-screw extruder (40 mmφ, L / D = 47) having an inlet at the center of the barrel was used. As the screw, a double screw having a kneading portion before and after the injection port was used. SBR (SBR-3 in Table 1) / PP / POX
/TAIC=70.0/30.0/0.5/1.0 (weight ratio), and the mixture was melt-extruded at a cylinder temperature of 220 ° C. At the time of this melt extrusion, a softener (P
W-380) was injected in an amount of 42 parts by weight. The degree of crosslinking of the obtained thermoplastic elastomer was 80%. This olefin matrix thermoplastic elastomer is called TPO. The composition of this TPO was SBR / PP / softener = 49.3 / 21.1 / 29.6 (weight ratio).

[0065]

EXAMPLES 1 TO 12 AND COMPARATIVE EXAMPLE 1 Using a Banbury mixer, dynamic crosslinking was carried out at a temperature of 220 to 240.degree. At this time, POX and TAIC were used as cross-linking agents, and the amount of addition was 0.2 parts by weight of POX and 0.2 parts by weight of TAIC based on 100 parts by weight of the rubbery polymer.
4 parts by weight, in Example 3, 0.33 parts by weight of POX, T
0.66 parts by weight of AIC;
50 parts by weight and TAIC were 1.00 parts by weight. The obtained thermoplastic elastomer was cut. The cut product was molded at 230 ° C. using an injection molding machine (Toshiba IS45PNV) to obtain a molded product. Table 2 shows the ratio and characteristics of each component of the molded article. In the table, () indicates the composition of the composition of the present invention.

[0066]

Comparative Example 2 The charge composition of Example 1 was changed to ESP / PS / P
A thermoplastic elastomer using ESP as the rubbery polymer was obtained in the same manner as in Example 1 except that OX / TAIC was used. The A hardness of the molded product obtained by molding was 88. This molded product was soft and elastomeric at room temperature, but when cooled to -10 ° C, it became hard and the performance as an elastomer was reduced. The molded product obtained in Example 1 did not change from room temperature even when cooled to -10 ° C, and showed excellent performance as an elastomer. The composition of the thermoplastic elastomer obtained here is represented by PS / ESP / softener =
It was 27.8 / 55.6 / 16.7 (weight ratio).

[0067]

Examples 14-17 Twin screw extruders (40 mmφ, L / D
= 47) and various polystyrene resins and TPO were melt-kneaded and extruded and pelletized with the charge compositions shown in Table 1. The cylinder temperature was 220 ° C. The obtained pellet was molded by an injection molding machine (Toshiba IS45PNV) to obtain a molded product. Table 2 shows the ratio and characteristics of each component of the molded article.
In the table, () indicates the composition of the composition of the present invention.

[0068]

Example 18 A thermoplastic elastomer was obtained from the rubbery polymer in the same manner as in Example 3 except that the SIR (isoprene / styrene ratio was 80/20, the degree of hydrogenation was 100%) was changed. To obtain a molded product. The composition of the resulting thermoplastic elastomer was PS / SIR / softener = 27.8.
/55.6/16.7. The composition of the composition of the present invention is composed of 33.3 parts by weight of the component (A) and 66.
7 parts by weight. The physical properties of the thermoplastic elastomer obtained here were as follows. A hardness: 86, tensile strength: 8.4 MPa, elongation: 260%, compression set: 7
5. Abrasion resistance: 0.023 g. Adhesion with HIPS and paintability are ◎ and ○, respectively.

[0069]

[Table 1]

[0070]

[Table 2]

[0071]

[Table 3]

[0072]

The matrix which is a fluid component of the present invention is a thermoplastic resin containing a polystyrene resin as an essential component, specifically a polystyrene resin or a mixture of a polystyrene resin and a resin other than a polystyrene resin,
Preferably, it is composed of a mixture of a polystyrene resin and a polyolefin resin, and the rubber component is a partially or completely crosslinked aromatic vinyl / conjugated diene block copolymer and / or a partially or completely hydrogenated polymer. A styrene-based thermoplastic elastomer composition composed of a rubber-like polymer composed of an aromatic vinyl / conjugated diene random copolymer is a material excellent in abrasion resistance, paintability, solvent adhesion, printability, and the like. This material can be widely used for applications such as packaging materials, materials for housing and building materials, materials for automobiles, materials for OA equipment, tools, toys, daily necessities and the like, and plays a large role in the industrial world.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C08L 53/02 C08L 53/02 F-term (Reference) 4F070 AA08 AA12 AA15 AA17 AA18 AB08 AB09 AC14 AC16 AC28 AC45 AC56 AE01 GA05 GB08 4J002 BB02X BB03X BB044 BB06X BB07X BB12X BB14X BB15X BC03W BC04W BC044 BP01Y BP02X BP03Y BP034 FA040 FD010 FD020

Claims (7)

[Claims] (A) a thermoplastic resin containing a polystyrene resin as an essential component; and (B) an aromatic vinyl / conjugated diene block copolymer and / or a hydrogenated aromatic vinyl / conjugated diene block copolymer. A composition comprising a partially or completely crosslinked rubbery polymer and, if necessary, (C) a compatibilizer, wherein component (A) + component (B) +
When the component (C) is 100 parts by weight, the component (B) in the composition is 40 to 90 parts by weight and the component (C) is less than 40 parts by weight. . 2. The styrenic thermoplastic elastomer composition according to claim 1, wherein the thermoplastic resin as the component (A) comprises a polystyrene resin. 3. The styrenic thermoplastic elastomer composition according to claim 1, wherein the thermoplastic resin as the component (A) comprises a polystyrene resin and a polyolefin resin. 4. The styrenic thermoplastic elastomer composition comprises a thermoplastic resin comprising a polystyrene resin as the component (A) or a thermoplastic resin comprising a polystyrene resin and a polyolefin resin, and a rubber comprising the component (B). The styrenic thermoplastic elastomer composition according to any one of claims 1 to 3, wherein the styrenic thermoplastic elastomer composition is obtained by dynamically crosslinking a polymer in the presence of a crosslinking agent. 5. The styrenic thermoplastic elastomer composition, wherein the thermoplastic resin as the component (A) comprises a polystyrene resin and a polyolefin resin, and the thermoplastic resin comprising the polyolefin resin as the component (A). The styrene-based thermoplastic elastomer composition according to claim 1, wherein the styrene-based thermoplastic elastomer composition is obtained by melt-mixing an olefin-based thermoplastic elastomer obtained by dynamically cross-linking a rubber-like polymer as the component (B) in the presence of a crosslinking agent and a polystyrene-based resin. object. 6. The styrene-based thermoplastic elastomer composition according to claim 3, wherein the polyolefin-based resin is mainly composed of a polypropylene-based resin. 7. The rubber-like polymer as the component (B) is 1 to
An aromatic vinyl / conjugated diene block copolymer and / or a hydrogenated aromatic vinyl / conjugated diene block copolymer comprising 70% by weight of an aromatic vinyl monomer and 99 to 30% by weight of a conjugated diene monomer; The styrenic thermoplastic elastomer composition according to any one of claims 1 to 6.