JP6838439B2 - Thermoplastic elastomer composition - Google Patents

Description

The present invention relates to a thermoplastic elastomer composition having excellent compressive permanent strain (sagging property) and cold resistance (low temperature brittleness resistance) of a molded product when molded, and also having good molding processability, and the thermoplastic elastomer composition. The present invention relates to a molded product using an object. The thermoplastic elastomer composition of the present invention and a molded product thereof are useful as a sealing material for automobiles, a sealing material for building materials, and the like.

The thermoplastic elastomer composition obtained by dynamically heat-treating a mixture containing a polypropylene resin and an ethylene / α-olefin copolymer in the presence of a cross-linking agent is vulcanized while exhibiting characteristics as a rubber-like soft material. It does not require a step and has the same molding processability as a thermoplastic resin. For this reason, such thermoplastic elastomer compositions are attracting attention from the viewpoints of rationalization of manufacturing processes and recyclability, and are widely used in the fields of automobile parts, home appliances, medical equipment parts, electric wires, miscellaneous goods, and the like. ..

In recent years, such thermoplastic elastomer compositions have not only molding processability but also compressive permanent strain (sagging property) and cold resistance in the obtained molded product in applications such as sealing materials for automobiles and sealing materials for building materials. Durability such as resistance (low temperature embrittlement resistance) is strongly required.

Conventionally, as a technique for obtaining good compression set, an olefin-based thermoplastic elastomer obtained by dynamically cross-linking a mixture of an olefin-based copolymer rubber, a softener for mineral oil-based rubber, and a polypropylene-based resin has been used. Patent Document 1 discloses a technique for mixing an olefin-based thermoplastic elastomer component having a bending elastic coefficient (JIS K7203) of 500 MPa or less and having no crosslinked structure.

Patent Document 2 discloses a thermoplastic elastomer composition having improved vibration damping properties and compression set by blending a styrene-vinylisoprene block copolymer as a cross-linking component with a crystalline olefin resin. However, polypropylene resin and ethylene / α-olefin copolymer are not used in combination as a resin component, and there is no description about improvement of cold resistance (low temperature brittleness resistance).

Japanese Unexamined Patent Publication No. 2006-36813 Japanese Unexamined Patent Publication No. 2006-117744

The thermoplastic elastomer composition described in Patent Document 1 has good compression set (sagging property), but the amount of a softener for mineral oil-based rubber is blended in order to further increase the compression set by good dispersion of rubber. If adjustments such as increasing the amount are made, the cold resistance (low temperature brittle resistance) becomes inferior. Further, in order to achieve both compression set and cold resistance (low temperature embrittlement resistance), if the ratio of rubber to the entire composition is increased, the moldability is greatly impaired. Therefore, compression set and cold resistance (low temperature embrittlement resistance) ) And moldability are all satisfied at the same time, and there is room for improvement.

Patent Document 2 describes a vibration-damping thermoplastic elastomer composition containing a styrene-vinyl isoprene block copolymer. Conventionally, the styrene-vinyl isoprene block copolymer has been an ethylene / α-olefin type. It is not known that it has the effect of directly binding to a copolymer (high rubber elastic component), improving compression set and cold resistance (low temperature brittleness resistance), and maintaining good molding processability. There is no description in 2 that suggests such an action and effect.

As described above, conventionally, a thermoplastic elastomer composition capable of improving compression set, cold resistance (low temperature embrittlement resistance) and molding processability at the same time has not yet been provided.

The present invention solves the above-mentioned problems of the prior art and provides a thermoplastic elastomer composition having excellent compression set (sagging property), cold resistance (low temperature embrittlement resistance) and molding processability. Make it an issue.

The present inventor has not conventionally known that a styrene-vinyl isoprene block copolymer known as a vibration damping component is effective in improving compression set and cold resistance (low temperature brittleness resistance). In addition, we obtained a new finding that it shows an effect completely different from the vibration damping property, and as a result of further studies, we found that block copolymers such as styrene-vinyl isoprene block copolymers, specific propylene resins, and ethylene were used. It has been found that the above problems can be solved by using α-olefin-based copolymer rubber in combination. The compression set, which is a subject of the present invention, is a performance that becomes good when the rubber elasticity is high, and is a performance that is inherently contradictory to the vibration damping property that becomes good when the rubber viscosity is high. The finding that the styrene-vinyl isoprene block copolymer contributes to the improvement of the compression set is characteristic and significant in the present invention.

That is, the gist of the present invention is as follows.

[1] A thermoplastic elastomer composition obtained by melt-kneading at least the following components (A) to (C) with a cross-linking agent.
Component (A): Polypropylene resin component (B): Ethylene / α-olefin copolymer rubber component (C): At least two polymer blocks mainly composed of vinyl aromatic compounds and isoprene as a main component. A block copolymer having at least one polymer block and / or a hydrogenated product thereof.

[2] The thermoplastic elastomer composition according to [1], wherein the component (B) is an ethylene / α-olefin / non-conjugated diene copolymer.

[3] The thermoplastic elastomer composition according to [1] or [2], wherein the component (C) is a non-hydrogenated block copolymer.

[4] The method according to any one of [1] to [3], wherein the ratio of the cross-linking agent to 100 parts by mass of the total amount of the components (A) to (C) is 0.05 parts by mass or more and 10 parts by mass or less. Thermoplastic elastomer composition.

[5] The thermoplastic elastomer composition according to any one of [1] to [4], wherein the component (A) is a polypropylene resin containing the following component (A1) and the component (A2).
Component (A1): Propylene-based polymer having a melting peak temperature of 157 ° C. or higher and 175 ° C. or lower Component (A2): Propylene-based random copolymer having a melting peak temperature of 100 ° C. or higher and lower than 157 ° C.

[6] The ratio of the component (A) to 100 parts by mass of the total amount of the component (A) and the component (B) is 40 to 70 parts by mass, and the ratio of the component (B) is 30 to 60 parts by mass. ] To [5]. The thermoplastic elastomer composition.

[7] The heat according to any one of [1] to [6], wherein the following component (D) is used as a raw material, and the ratio thereof is 40 to 320 parts by mass with respect to 100 parts by mass of the component (B). Thermoplastic elastomer composition.
Component (D): Hydrocarbon-based rubber softener

[8] A molded product using the thermoplastic elastomer composition according to any one of [1] to [7].

[9] The molded product according to [8], which is a member for an automobile.

[10] The molded product according to [9], which is a glass run channel for automobiles.

The thermoplastic elastomer composition of the present invention is excellent in compression set (sag resistance) and cold resistance (low temperature brittleness resistance) of the molded product when molded, and also has good molding processability, and the heat of the present invention. By using the thermoplastic elastomer composition, a molded product having excellent compression set (sagging property) and cold resistance (low temperature brittleness resistance) can be obtained under good molding processability.
The thermoplastic elastomer composition and molded product of the present invention can be used as a sealant for automobiles and a sealant for building materials due to their excellent compression set (sag resistance), cold resistance (low temperature embrittlement resistance) and molding processability. It is useful, especially as a glass run channel for automobiles.

Hereinafter, the present invention will be described in detail, but the present invention is not limited to the following description, and can be arbitrarily modified and carried out without departing from the gist of the present invention. In addition, in this specification, when a numerical value or a physical property value is put before and after using "~", it is used as including the value before and after that.

[Method for Producing Thermoplastic Elastomer Composition]
The thermoplastic elastomer composition of the present invention is formed by melt-kneading at least the following components (A) to (C) and a cross-linking agent.
Component (A): Polypropylene resin component (B): Ethylene / α-olefin copolymer rubber component (C): At least two polymer blocks mainly composed of vinyl aromatic compounds and isoprene as a main component. A block copolymer having at least one polymer block and / or a hydrogenated product thereof.

[mechanism]
The thermoplastic elastomer composition of the present invention has the effect that the obtained molded product has excellent compression set (sagging property) and cold resistance (low temperature embrittlement resistance), and also has good molding processability.
Although the details of the reason why the thermoplastic elastomer composition of the present invention exerts such an effect are not clear, the component (C) forms a dispersion while incorporating the component (B) which is a component expressing rubber elasticity (B). By acting as the core of the rubber dispersion), a clear rubber domain phase is formed with the polypropylene phase of the component (A), and it is considered that the compression set (sagging property) is improved. It is speculated that this is because the component (B) and the component (C) can have reactive groups on the side chains of each other, and they are cross-linked and linked. Further, since the component (B) and the component (C) are dispersed as described above and the performance is not deteriorated due to poor dispersion, the ratio of the rubber component (particularly the component (B) exhibiting elasticity at low temperature) in the entire composition is set. It is considered that the temperature can be increased and the cold resistance (low temperature embrittlement resistance) can be improved.
Further, it is considered that the fluidity does not become excessively large as the cross-linking reaction proceeds as described above, and excellent molding processability can be obtained.
As in Patent Document 2 described above, conventionally, the flexibility and vibration damping of a molded product obtained by simultaneously using an ethylene / α-olefin copolymer rubber and a block copolymer rubber mainly composed of a vinyl aromatic compound are used. Although methods for improving the properties are generally well known, a cross-linking system is used, and the synergistic effect of the cross-linking system satisfies the performances of permanent compressive strain (sagging property) and cold resistance (low temperature embrittlement resistance), and further molding. The technique for improving workability is the first established by the present invention.

[Component (A)]
The component (A) used in the thermoplastic elastomer composition of the present invention is preferably a polypropylene-based resin containing the following components (A1) and (A2), and if these are contained, other polypropylene-based resins may be used. It may include. In the present invention, the "polypropylene resin" means a resin having a propylene unit content of 50% by mass or more. In the present invention, the component (A) mainly contributes to extrusion moldability.
Component (A1): Propylene-based polymer having a melting peak temperature of 157 ° C. or higher and 175 ° C. or lower Component (A2): Propylene-based random copolymer having a melting peak temperature of 100 ° C. or higher and lower than 157 ° C.

The melting peak temperature of the component (A1) and the component (A2) can be measured by the following method according to JIS K7121.
That is, using a differential scanning calorimeter (DSC6220 manufactured by SSI Nanotechnology Co., Ltd.), the following steps (1) to (3) are sequentially performed to measure the melting behavior of the polypropylene resin.
In each process, time is plotted on the horizontal axis and heat of fusion is plotted on the vertical axis to obtain a melting curve, and the peak peak of the peak observed in step (3) is defined as the melting peak temperature.
Step (1): The temperature of 5 mg of the sample is raised from room temperature to 100 ° C./min at a rate of 40 ° C. to 200 ° C., and the temperature is maintained for 3 minutes after the temperature rise is completed.
Step (2): The temperature is lowered from 200 ° C. to 40 ° C. at a rate of 10 ° C./min, and after the temperature reduction is completed, the temperature is maintained for 3 minutes.
Step (3): The temperature is raised from 40 ° C. to 200 ° C. at a rate of 10 ° C./min.

The propylene-based polymer of the component (A1) has a melting peak temperature of 157 ° C. or higher and 175 ° C. or lower. The component (A1) is a component that mainly imparts heat resistance to the thermoplastic elastomer composition.

Heat resistance is imparted when the melting peak temperature of the component (A1) is 157 ° C. or higher. From this point of view, the melting peak temperature of the component (A1) is preferably 160 ° C. or higher. On the other hand, the upper limit is 175 ° C. or lower, preferably 170 ° C. or lower.

In the propylene-based polymer of the component (A1), the content of the propylene unit is preferably 90% by mass or more, more preferably 98 to 100% by mass, based on the total amount of the monomer units constituting the component (A1). Is. It is preferable that the content of the propylene unit of the component (A1) is in the above range because it tends to be in the above-mentioned melting peak temperature range. The content of each structural unit of the component (A1) can be determined by infrared spectroscopy. The same applies to the component (A2) and the component (B) described later.

The component (A1) may be a propylene homopolymer, a random copolymer, or a block copolymer, but it is preferable that the component (A1) contains a propylene homopolymer.

The propylene-based polymer of the component (A1) may have a structural unit other than propylene, and may include, for example, a polymer copolymerized with an α-olefin other than ethylene or propylene. In this case, the α-olefin unit that the component (A1) may contain includes, for example, 1-butene unit, 1-pentene unit, 1-hexene unit, 1-hepten unit, 1-octene unit, 1-. Nonen unit, 1-decene unit, 1-undecene unit, 1-dodecene unit, 1-tridecene unit, 1-tetradecene unit, 1-pentadecene unit, 1-hexadecene unit, 1-heptadecene unit, 1-octadecene unit, 1- Nonadecene unit, 1-eicosene unit, 3-methyl-1-butene unit, 3-methyl-1-pentene unit, 4-methyl-1-pentene unit, 2-ethyl-1-hexene unit, 2,2,4- Examples include the trimethyl-1-pentene unit. The component (A1) may contain only one of these kinds, or may contain two or more kinds. When the component (A1) contains a structural unit other than the propylene unit, preferred examples of the other structural unit include ethylene unit and 1-butene unit.

The propylene-based random copolymer of the component (A2) has a melting peak temperature of 100 ° C. or higher and lower than 157 ° C. The component (A2) is a component for improving the compatibility between the component (A) and the component (B).

The melting peak temperature of the component (A2) is 100 ° C. or higher, preferably 125 ° C. or higher. On the other hand, the melting peak temperature of the component (A2) is less than 157 ° C. When the melting peak temperature of the component (A2) is at least the above lower limit value, it is preferable from the viewpoint of heat resistance, and when it is less than the above upper limit value, it is preferable from the viewpoint of compatibility between the component (A) and the component (B).

In the propylene-based random copolymer of the component (A2), the content of the propylene unit is preferably 60 to 99% by mass, more preferably 60% by mass, based on the total amount of the monomer units constituting the component (A2). It is 80 to 98% by mass. It is preferable that the content of the propylene unit of the component (A2) is in the above range because it tends to be in the above-mentioned melting peak temperature range.

The propylene-based random copolymer of the component (A2) is a copolymer having a propylene unit and a constituent unit other than the propylene unit. Specific examples of the constituent unit other than the propylene unit include an ethylene unit and an α-olefin unit other than the propylene unit. Examples of the constituent units other than the propylene unit that the component (A2) may contain include ethylene unit, 1-butene unit, 1-pentene unit, 1-hexene unit, 1-hepten unit, 1-octene unit, and the like. 1-Nonene unit, 1-decene unit, 1-undecene unit, 1-dodecene unit, 1-tridecene unit, 1-tetradecene unit, 1-pentadecene unit, 1-hexadecene unit, 1-heptadecene unit, 1-octadecene unit, 1-nonadecene unit, 1-eicosene unit, 3-methyl-1-butene unit, 3-methyl-1-pentene unit, 4-methyl-1-pentene unit, 2-ethyl-1-hexene unit, 2,2 Examples include 4-trimethyl-1-pentene unit. The component (A2) may contain only one of these kinds, or may contain two or more kinds. Preferable constituent units other than the propylene unit contained in the component (A2) include ethylene units and 1-butene units.

As a method for producing the propylene-based polymer of the component (A1) and the component (A2), a known polymerization method using a known catalyst for olefin polymerization is used. For example, a polymerization method using a Ziegler-Natta catalyst can be mentioned. As the polymerization method, a slurry polymerization method, a solution polymerization method, a massive polymerization method, a gas phase polymerization method and the like can be used, and two or more of these may be combined.

The component (A1) and the component (A2) can also be obtained as commercial products. Commercial products that fall under these categories include Prime Polymer Co., Ltd.'s Prim Polypro (registered trademark), Sumitomo Chemical Co., Ltd.'s Sumitomo Noblen (registered trademark), SunAllomer Ltd.'s polypropylene block copolymer, Japan Polypropylene Corporation's Novatec (registered trademark) PP, and Lyondell Basell. Moplen®, ExxonMobile's ExxonMobile PP, Formosa Plastics'Formole®, Borearis' Borealis PP, LG Chemical's SEETEC PP, A.M. Schulman's ASI POLYPROPYLENE, INEOS Olefins & Polymers, Inc. of INEOS PP, Braskem's Braskem PP, SAMSUNG TOTAL PETROCHEMICALS's Sumsung Total, Sabic's Sabic (registered trademark) PP, TOTAL PETROCHEMICALS company of TOTAL PETROCHEMICALS Polypropylene, SK Corporation of YUPLENE ( There are registered trademarks), etc., and they can be appropriately selected from these and used in combination.

Only one kind of component (A1) and one kind of component (A2) may be used, or two or more kinds having different compositions and physical properties may be used in combination.

The content of the component (A1) is preferably 50 parts by mass or more, preferably 50 parts by mass or more, with respect to 100 parts by mass of the total amount of the component (A1) and the component (A2) from the viewpoint of heat resistance, rigidity, dispersibility and the like. It is more preferably parts by mass or more, and even more preferably 70 parts by mass or more. On the other hand, from the viewpoint of compatibility between the component (A) and the component (B), the content of the component (A1) is 95 parts by mass or less with respect to 100 parts by mass of the total amount of the component (A1) and the component (A2). It is preferably 90 parts by mass or less, more preferably 85 parts by mass or less.

The component (A) may contain a polypropylene-based resin other than the component (A1) and the component (A2), but in order to effectively obtain the effects of the component (A1) and the component (A2), The component (A) preferably contains 30 parts by mass or more, more preferably 40 parts by mass or more, and 50 to 100 parts by mass of the component (A1) and the component (A2) in 100 parts by mass. Is even more preferable.

[Component (B)]
The component (B) used in the thermoplastic elastomer composition of the present invention is an ethylene / α-olefin copolymer rubber (however, excluding those corresponding to the component (A)). The component (B) is a component that imparts flexibility to the thermoplastic elastomer of the present invention.

The component (B) is not particularly limited as long as it is a copolymer containing at least an ethylene unit and an α-olefin unit, but is preferably an ethylene / α-olefin / non-conjugated diene copolymer further containing a non-conjugated diene unit. is there.

The α-olefin unit contained in the component (B) includes 1-propylene unit, 1-butene unit, 2-methylpropylene unit, 1-pentene unit, 3-methyl-1-butene unit, 1-hexene unit, and 4 Examples thereof include −methyl-1-pentene unit and 1-octene unit. The α-olefin unit used in the component (B) is preferably the number of carbon atoms having an intercarbon double bond at the terminal carbon atom such as 1-propylene unit, 1-butene unit, 1-hexene unit, 1-octene unit and the like. It is an α-olefin unit of 3 to 8. The component (B) may contain only one of these α-olefin units, or may contain two or more of these α-olefin units.

The non-conjugated diene unit contained in the component (B) includes 1,4-hexadiene, 1,6-octadene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-. Units based on chain non-conjugated diene such as 1,6-octadene; cyclohexadiene, dicyclopentadiene, methyltetrahydroinden, 5-vinylnorbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, Examples include units based on cyclic non-conjugated diene such as 5-isopropylidene-2-norbornene and 6-chloromethyl-5-isopropenyl-2-norbornene. Of these, 5-ethylidene-2-norbornene units and dicyclopentadiene units are preferable.
The component (B) may contain only one of these non-conjugated diene units, or may contain two or more of these non-conjugated diene units.

The content of the ethylene unit of the component (B) is preferably 30% by mass or more, more preferably 40% by mass or more, still more preferably, with respect to the total amount of the monomer units constituting the component (B). Is 50% by mass or more, preferably 90% by mass or less, and more preferably 80% by mass or less. It is preferable that the content of ethylene units is in the above range because it gives appropriate flexibility.

In the component (B), the content of the α-olefin unit is preferably 10% by mass or more, more preferably 20% by mass or more, based on the total amount of the monomer units constituting the component (B). On the other hand, it is preferably 50% by mass or less, and more preferably 40% by mass or less. It is preferable that the content of the α-olefin unit is in the above range in order to give appropriate flexibility.

In the component (B), the content of the non-conjugated diene unit is preferably 1% by mass or more, preferably 3% by mass or more, based on the total amount of the monomer units constituting the component (B). On the other hand, it is preferably 10% by mass or less, and preferably 8% by mass or less. When the content of the non-conjugated diene unit is at least the above lower limit value, it is preferable from the viewpoint of increasing the degree of cross-linking of the thermoplastic elastomer composition, and when it is at least the above upper limit value, it is preferable from the viewpoint of moldability.

The Mooney viscosity (ML _{1 + 4} , 125 ° C.) of the component (B) is usually 30 to 120, preferably 40 to 100. It is preferable that the Mooney viscosity (ML _{1 + 4} , 125 ° C.) of the component (B) is in the above range from the viewpoint of moldability.

The density of the component (B) is ^{preferably 0.850 g / cm 3} or more, more preferably 0.860 g / cm ³ or more, and preferably 0.900 g / cm ³ or less. More preferably, it is 0.890 g / cm ^{3 or less.} When the density of the component (B) is at least the above lower limit value, it is preferable from the viewpoint of workability, while when it is at least the above upper limit value, it is preferable from the viewpoint of flexibility. The density of component (B) can be measured based on JIS K7112.

The melt flow rate of the component (B) is not limited, but is usually less than 10 g / 10 minutes, preferably 9.0 g / 10 minutes or less, and more preferably 8.0 g / 10 minutes or less from the viewpoint of strength. Yes, more preferably 7.0 g / 10 minutes or less. The melt flow rate of the component (B) is usually 0.01 g / 10 minutes or more, preferably 0.05 g / 10 minutes or more, and more preferably 0.10 g / 10 minutes from the viewpoint of fluidity. That is all. The melt flow rate (MFR) of the component (B) is measured according to JIS K7210 under the conditions of a measurement temperature of 230 ° C. and a measurement load of 49 N.

As a method for producing the component (B), a known polymerization method using a known catalyst for olefin polymerization is used. For example, a slurry polymerization method, a solution polymerization method, a massive polymerization method, a gas phase polymerization method and the like using a Ziegler-Natta catalyst, a complex catalyst such as a metallocene complex or a non-metallocene complex can be mentioned.

A commercially available product can also be used as the component (B). For example, JSR EPT manufactured by JSR, Mitsui EPT manufactured by Mitsui Chemicals, Esplen (registered trademark) manufactured by Sumitomo Chemical, Keltan (registered trademark) manufactured by LANXESS, Nordel (registered trademark) manufactured by Dow, and Vistalon (registered trademark) manufactured by ExxonMobil. ) Etc. can be selected and used.

As the component (B), only one type may be used, or two or more types having different compositions and physical properties may be used in combination.

[Ratio of component (A) and component (B)]
In the method for producing a thermoplastic elastomer composition of the present invention, the lower limit of the amount of the component (A) used is usually 100 parts by mass, which is the total amount of the component (A) and the component (B), from the viewpoint of moldability. It is 40 parts by mass or more, preferably 42 parts by mass or more, and more preferably 44 parts by mass or more. On the other hand, the upper limit is usually 70 parts by mass or less, preferably 68 parts by mass or less, and more preferably 66 parts by mass or less.
The lower limit of the content of the component (B) is usually 30 parts by mass or more and 32 parts by mass or more from the viewpoint of moldability with respect to 100 parts by mass of the total amount of the component (A) and the component (B). It is preferably 34 parts by mass or more, and more preferably 34 parts by mass or more. On the other hand, the upper limit is usually 60 parts by mass or less, preferably 58 parts by mass or less, and more preferably 56 parts by mass or less.

[Component (C)]
The component (C) used in the thermoplastic elastomer composition of the present invention is mainly composed of at least two polymer blocks (hereinafter, may be referred to as "block P") mainly composed of a vinyl aromatic compound and isoprene. A block copolymer having at least one polymer block (hereinafter, may be referred to as “block Q”) and / or a hydrogenated product thereof (hydrogenated block copolymer).

Here, the "polymer mainly composed of a vinyl aromatic compound" means a polymer obtained by polymerizing a monomer mainly composed of a vinyl aromatic compound, and the "polymer mainly composed of isoprene" means isoprene. It means a polymer of a monomer mainly composed of. Further, here, "mainly" means that it is 50 mol% or more.

The monomeric vinyl aromatic compound constituting the block P is not limited, but a styrene derivative such as styrene or α-methylstyrene is preferable. Above all, it is preferable to mainly use styrene. The block P may contain a monomer other than the vinyl aromatic compound as a raw material.

Block Q may contain a monomer other than isoprene, for example, butadiene as a raw material.

The block Q may be a hydrogenated derivative (hydrogenated block copolymer) in which a double bond held after polymerization is hydrogenated, but from the viewpoint of reactivity with the component (B), the non-hydrogenated block co-weight is used. It is preferably coalesced.

The weight ratio of the block P in the block copolymer of the component (C) is not limited, but is preferably 5% by mass or more, more preferably 10% by mass or more, and 55% by mass or less. Is more preferable, and it is more preferably 50% by mass or less, and further preferably 45% by mass or less. When the weight ratio of the block P is in the above range, the ratio of the cross-linking reaction tends to be good.

The chemical structure of the block copolymer of the component (C) may be linear, branched, radial or the like, but it is a block copolymer represented by the following formula (1) or (2). The case is preferable, and from the viewpoint of improving the mechanical strength, the structure of the following formula (1) is more preferable.

P- (QP) m (1)
(PQ) n (2)
(In the formula, P represents block P, Q represents block Q, m represents an integer of 1 to 5, and n represents an integer of 2 to 5).

In the formula (1) or (2), m and n should be large in terms of lowering the order-disorder transition temperature as a rubber polymer, but should be small in terms of ease of manufacture and cost. .. In the present invention, m and n are preferably given as integers of 1 to 5, more preferably 2 to 4.

As the block copolymer of the component (C), the block copolymer represented by the formula (1) is preferable to the block copolymer represented by the formula (2) because it is excellent in rubber elasticity. The block copolymer represented by the formula (1) in which m is 3 or less is more preferable, and the block copolymer represented by the formula (1) in which m is 2 or less is further preferable.

The number average molecular weight of the block copolymer of component (C) is not limited, but it is preferably 20000 or more as a polystyrene-equivalent value measured by gel permeation chromatography (hereinafter, may be abbreviated as GPC). It is more preferably 40,000 or more, further preferably 50,000 or more, preferably 300,000 or less, more preferably 200,000 or less, still more preferably 150,000 or less, and particularly preferably 100,000 or less.

When the number average molecular weight of the block copolymer of the component (C) is within the above range, the moldability tends to be good.

The method for producing the component (C) in the present invention may be any method as long as the above-mentioned structure and physical properties can be obtained, and is not particularly limited. Specifically, for example, it can be obtained by performing block polymerization using a lithium catalyst or the like by the method described in JP-A-7-97493. Further, hydrogenation (hydrogenation) of the block copolymer can be carried out in the presence of a hydrogenation catalyst in an inert solvent, for example, by the method described in JP-A-59-133203.

Examples of commercially available hydrogenated block copolymers of component (C) include "Septon (registered trademark)" and "Hybler (registered trademark)" manufactured by Kuraray Co., Ltd. Examples of commercially available non-hydrogenated block copolymers of component (C) include some grades of "Hybler (registered trademark)" manufactured by Kuraray Co., Ltd.

As the above component (C), only one kind may be used, or two or more kinds having different compositions and physical properties may be used in combination.

In the present invention, the amount of the component (C) used is 0.1 to 100 parts by mass with respect to a total of 100 parts by mass of the component (A) and the component (B) and the component (D) described later used as needed. Is preferable. When the component (C) is at least the lower limit value in the above range, good fluidity can be obtained, and when it is at least the upper limit value, compression set (sagging property) and mechanical properties are good. The component (C) is more preferably 10 parts by mass or more, more preferably 11 parts by mass or more, based on 100 parts by mass in total of the component (A) and the component (B) and the component (D) described later which is used as needed. It is more preferable to use, and it is particularly preferable to use 12 parts by mass or more. Further, the component (C) is preferably used in an amount of 95 parts by mass or less, preferably 94 parts by mass or less, based on 100 parts by mass in total of the component (A) and the component (B) and the component (D) described later used as needed. It is more preferable to use below, and it is further preferable to use 93 parts by mass or less.
Further, in order for the component (C) to form a dispersion while incorporating the component (B) which is an expression component of rubber elasticity, the component (B) is preferably a smaller amount component than the component (C). For example, the component (B) is preferably used in a mass ratio of 1/5 to 4/5 with respect to the component (C).

[Component (D)]
From the viewpoint of improving moldability, the thermoplastic elastomer composition of the present invention preferably further uses the following component (D) as a raw material.
Component (D): Hydrocarbon-based rubber softener

Examples of the hydrocarbon-based rubber softener of the component (D) include mineral oil-based softeners, synthetic resin-based softeners, and the like, but mineral oil-based softeners are preferable from the viewpoint of compatibility with other components. Mineral oil-based softeners are generally a mixture of aromatic hydrocarbons, naphthenic hydrocarbons and paraffinic hydrocarbons, and paraffinic oils in which 50% or more of all carbon atoms are paraffinic hydrocarbons. Those in which 30 to 45% of all carbon atoms are naphthenic hydrocarbons are called naphthenic oils, and those in which 35% or more of all carbon atoms are aromatic hydrocarbons are called aromatic oils. Among these, in the present invention, it is preferable to use paraffinic oil. The hydrocarbon softener for rubber may be used alone or in any combination and ratio of two or more.

The kinematic viscosity of the hydrocarbon softener of the component (D) at 40 ° C. is not particularly limited, but is preferably 20 cSt or more, more preferably 50 cSt or more, and preferably 800 cSt or less, more preferably 600 cSt or less. is there. The flash point (COC method) of the hydrocarbon softener is preferably 200 ° C. or higher, more preferably 250 ° C. or higher.

The hydrocarbon-based rubber softener of component (D) can be obtained as a commercially available product. Examples of applicable commercial products include Nisseki Polybutene (registered trademark) HV series manufactured by JX Nikko Nisseki Energy Co., Ltd., Diana (registered trademark) process oil PW series manufactured by Idemitsu Kosan Co., Ltd., and the like. Can be appropriately selected and used.

When the component (D) is used in the production of the thermoplastic elastomer composition of the present invention, the lower limit of the amount of the component (D) used is preferably 40 parts by mass with respect to 100 parts by mass of the component (B) from the viewpoint of flexibility. It is 4 parts or more, more preferably 42 parts by mass or more, and further preferably 44 parts by mass or more. The upper limit of the amount of the component (D) used is usually 320 parts by mass or less, preferably 318 parts by mass or less, more preferably 318 parts by mass or less, with respect to 100 parts by mass of the component (B) from the viewpoint of low temperature impact resistance. Is 316 parts by mass or less.

[Crosslinking agent]
The thermoplastic elastomer composition of the present invention is subjected to dynamic heat treatment in the presence of a cross-linking agent (hereinafter, may be referred to as “component (E)”) to at least the component (B) and the component (C). Obtained by partially cross-linking. By this dynamic heat treatment, the thermoplastic elastomer composition of the present invention has good rubber elasticity.

As the cross-linking agent, an organic peroxide, a phenol resin, another cross-linking aid, or the like can be used, and these cross-linking agents may be used alone or in combination of two or more.

As the organic peroxide that can be used as a cross-linking agent, either an aromatic organic peroxide or an aliphatic organic peroxide can be used. Specifically, di-t-butylperoxide, t-butylcumylperoxide, dicumylperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl. -2,5-di (t-butylperoxy) hexin-3,1,3-bis (t-butylperoxyisopropyl) benzene, 1,1-di (t-butylperoxy) -3,3,5 Dialkyl peroxides such as -trimethylcyclohexane; t-butylperoxybenzoate, t-butylperoxyisopropyl carbonate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5-dimethyl-2 Peroxyesters such as 5-di (benzoyl peroxy) hexin-3; hydropers such as acetyl peroxide, lauroyl peroxide, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, etc. Examples include oxides. Among these, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane is preferable. These organic peroxides may be used alone or in combination of two or more.

Examples of the phenol resin that can be used as a cross-linking agent include alkylphenol formaldehyde, alkylphenol norformaldehyde bromide, and the like. These phenol resins may be used alone or in combination of two or more.

Examples of cross-linking aids other than organic peroxides and phenolic resins include peroxide aids such as sulfur, p-quinonedioxime, p-dinitrosobenzene, and 1,3-diphenylguanidine; stannous chloride. -Crossing aids for phenolic resins such as anhydrides, stannous chloride / dihydrate, ferric chloride; polyfunctional vinyl compounds such as divinylbenzene, triallyl cyanurate, triallyl isocyanurate, diallyl phthalate; ethylene Examples thereof include polyfunctional (meth) acrylate compounds such as glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, trimethylpropantri (meth) acrylate, and allyl (meth) acrylate. These may be used alone or in combination of two or more.

The amount of the component (E) used is from the viewpoint of sufficiently proceeding the cross-linking reaction with respect to a total of 100 parts by mass of the component (A), the component (B), the component (C) and the component (D) used as needed. Therefore, it is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, and further preferably 0.3 parts by mass or more. On the other hand, the amount of the component (E) used is from the viewpoint of controlling the cross-linking reaction with respect to a total of 100 parts by mass of the component (A), the component (B) and the component (C) and the component (D) used as needed. Therefore, it is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and further preferably 6 parts by mass or less.

[Other ingredients]
In the production of the thermoplastic elastomer composition of the present invention, other components other than the components (A) to (E) can be used as raw materials as needed, as long as the effects of the present invention are not impaired.

Examples of other components include resins other than the component (A), the component (B) and the component (C), resins such as elastomers, antioxidants, fillers, heat stabilizers, light stabilizers, and ultraviolet absorbers. Agents, neutralizers, lubricants, antifogging agents, antiblocking agents, slip agents, dispersants, colorants, flame retardants, antistatic agents, conductivity-imparting agents, metal inactivating agents, molecular weight modifiers, antibacterial agents , Various additives such as antifungal materials and fluorescent whitening agents can be mentioned. Any of these can be used alone or in combination.

Examples of the thermoplastic resin other than the component (A), the component (B) and the component (C) include a polyphenylene ether-based resin; a polyamide-based resin such as nylon 6 and nylon 66; and a polyester-based resin such as polyethylene terephthalate and polybutylene terephthalate. Resins: Polyoxymethylene homopolymers, polyoxymethylene copolymers and other polyoxymethylene resins; polymethylmethacrylate resins, polyolefin resins (excluding those corresponding to component (A) and component (B)), etc. Can be mentioned. Examples of elastomers other than the component (A), the component (B) and the component (C) include styrene-based elastomers (excluding those corresponding to the component (C)); polyester-based elastomers; polybutadiene and the like. be able to.

Examples of the antioxidant include a phenol-based antioxidant, a sulfide-based antioxidant, a thioether-based antioxidant, and the like. When an antioxidant is used, the antioxidant is usually 0.01 with respect to a total of 100 parts by mass of the component (A), the component (B) and the component (C) and the component (D) used as needed. It is used in the range of ~ 3.0 parts by mass.

Examples of the filler include glass fiber, hollow glass ball, carbon fiber, talc, calcium carbonate, mica, potassium titanate fiber, silica, metal soap, titanium dioxide, carbon black and the like. When a filler is used, the filler is usually 0.1 to 50 parts by mass of a total of 100 parts by mass of the component (A), the component (B) and the component (C) and the component (D) used as needed. Used in parts by mass.

[Manufacturing method of thermoplastic elastomer composition]
As described above, the thermoplastic elastomer composition of the present invention contains a predetermined amount of the component (A), the component (B), the component (C), the component (D) used as necessary, and other components. It is obtained by dynamically heat-treating a product in the presence of the component (E) which is a cross-linking agent.

In the present invention, "dynamic heat treatment" means kneading in a molten state or a semi-molten state in the presence of a cross-linking agent. This dynamic heat treatment is preferably performed by melt-kneading, and as the mixing and kneading device for that purpose, for example, a non-open type Banbury mixer, a mixing roll, a kneader, a twin-screw extruder and the like are used. Among these, it is preferable to use a twin-screw extruder. A preferred embodiment of the manufacturing method using this twin-screw extruder is to supply each component to a raw material supply port (hopper) of a twin-screw extruder having a plurality of raw material supply ports to perform dynamic heat treatment.

The temperature at which the dynamic heat treatment is performed is usually 80 to 300 ° C, preferably 100 to 250 ° C. The time for performing the dynamic heat treatment is usually 0.1 to 30 minutes.

When the thermoplastic elastomer composition of the present invention is produced by performing dynamic heat treatment with a twin-screw extruder, the barrel radius (R (mm)) and screw rotation speed (N (rpm)) of the twin-screw extruder are used. It is preferable to extrude while maintaining the relationship of the following formula (1) between and the discharge amount (Q (kg / hour)), and it is more preferable to extrude while maintaining the relationship of the following formula (2).
2.6 <NQ / R ³ <22.6 (1)
3.0 <NQ / R ³ <20.0 (2)

Thermoplasticity means that the relationship between the barrel radius (R (mm)), screw rotation speed (N (rpm)) and discharge amount (Q (kg / hour)) of the twin-screw extruder is larger than the above lower limit. It is preferable for efficiently producing the elastomer composition. On the other hand, it is preferable that the relationship is smaller than the above upper limit value because heat generation due to shearing is suppressed and foreign matter that causes poor appearance is less likely to be generated.

[Physical characteristics of thermoplastic elastomer composition]
The thermoplastic elastomer composition of the present invention has a moldability of 0.10 g / 10 minutes or more in terms of melt flow rate (MFR) measured at a measurement temperature of 230 ° C. and a measurement load of 49 N by a method conforming to JIS K7210 standards. From the above viewpoint, it is preferably 0.15 g / 10 minutes or more, and further preferably 0.20 g / 10 minutes or more. From the viewpoint of moldability, the melt flow rate (MFR) is preferably 1 g / 10 minutes or less, more preferably 0.95 g / 10 minutes or less, and 0.90 g / 10 minutes or less. Is even more preferable.

Further, with respect to the molded product obtained by molding the thermoplastic elastomer composition of the present invention, the compression set is less than 51% measured under the conditions of 70 ° C., 22 hours and 25% compression in accordance with JIS K6262. It is preferably less than 45%.

[Molded body / application]
The thermoplastic elastomer composition of the present invention can be made into a molded product by various molding methods usually used for the thermoplastic elastomer composition, for example, injection molding, extrusion molding, hollow molding, compression molding and the like. Of these, injection molding and extrusion molding are preferable. Further, it is also possible to obtain a molded product obtained by performing secondary processing such as laminating molding and thermoforming after performing these moldings. In particular, the thermoplastic elastomer composition of the present invention is excellent in extrusion moldability, and is suitable for extrusion molding, particularly irregular shape extrusion molding, because it reduces the generation of grain tar and foreign matter during molding.

The molded body made of the thermoplastic elastomer composition of the present invention is an automobile part such as a skin, a weather strip, a ceiling material, an interior sheet, a bumper molding, a side molding, an air spoiler, an air duct hose, and a sealing material; Civil engineering and building material parts such as window frames and sealing materials; Sporting goods such as golf club grips and tennis racket grips; Industrial parts such as hose tubes and gaskets; Home appliances parts such as hoses and packings; Medical use It can be applied to a wide range of fields such as medical parts such as containers, gaskets and packings; food parts such as containers and packings; medical equipment parts; electric wires; miscellaneous goods and the like.
Among those listed above, the molded product made of the thermoplastic elastomer composition of the present invention is suitable as a sealing material for automobiles and a sealing material for building materials, and is suitable as a sealing material for automobiles, particularly as a glass run channel for automobiles.

Hereinafter, the content of the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist of the present invention is not exceeded. The values of various production conditions and evaluation results in the following examples have meanings as preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable ranges are the above-mentioned upper limit or lower limit values and the following. It may be in the range specified by the value of Examples or the combination of the values of Examples.

〔raw materials〕
The raw materials used in the following examples and comparative examples are as follows.

[Component (A): Polypropylene resin]
<A1-1>
Propylene homopolymer (melting peak temperature: 165 ° C, propylene unit content: 100% by mass) / Novatec (registered trademark) PP FY6 manufactured by Japan Polypropylene Corporation

<A2-1>
Propylene / ethylene random copolymer (melting peak temperature: 138 ° C., propylene unit content: 98% by mass) / Novatec (registered trademark) PP FW4B manufactured by Japan Polypropylene Corporation

[Component (B): Ethylene / α-olefin copolymer rubber]
<B-1>
Ethylene / propylene / 5-ethylidene-2-norbornene copolymer (Moonie viscosity (ML _{1 + 4} , 125 ° C.): 61, density (JIS K7112): 0.87 g / cm ³ , MFR (JIS K7210, 230 ° C., 49N)) : 6 g / 10 minutes, ethylene unit content: 65.9 mass%, ethylidene norbornene unit content: 4.6 mass%) / Mitsui Chemicals Co., Ltd. JSR EPT3092PM
<B-2>
Ethylene / propylene / 5-ethylidene-2-norbornene copolymer (Moonie viscosity (ML1 + 4, 125 ° C.): 64, density (JIS K7112): 0.86 g / cm ³ , MFR (JIS K7210, 230 ° C., 98N): 0.4 g / 10 minutes, ethylene unit content: 67% by mass, ethylylidene norbornene unit content: 4.5% by mass) / JSR EP505EC manufactured by JSR Corporation

[Component (C): A block copolymer having at least two polymer blocks mainly composed of a vinyl aromatic compound and at least one polymer block mainly composed of isoprene, and / or a hydrogenated product thereof]
<C-1>
Styrene / isoprene / styrene non-hydrogenated block copolymer (having the structure of the above formula (1). Styrene (block P) content: 20% by mass, number average molecular weight: 90000) / Hybler 5127 manufactured by Kuraray Co., Ltd.

[Comparative component (C)]
<C-1>
Styrene-butadiene-styrene non-hydrogenated block copolymer (having the structure of the above formula (1). Styrene (block P) content: 60% by mass, number average molecular weight: 200,000) / Asahi Kasei Chemicals Co., Ltd. S1605

[Component (D)]
<D-1>
Paraffin-based rubber softener (kinematic viscosity at 40 ° C: 95.5 cSt, pour point: -15 ° C, flash point: 272 ° C) / Diana (registered trademark) process oil PW90 manufactured by Idemitsu Kosan Co., Ltd.

[Component (E): Crosslinking agent]
<E-1>
A mixture of 40% by mass of 2,5-dimethyl-2,5-di (t-butylperoxy) hexane and 60% by mass of calcium carbonate / Kayaku Akzo Corporation Kayahexa AD40C
<E-2>
Mixture of 60% by mass of divinylbenzene and 40% by mass of ethylvinylbenzene / Divinylbenzene manufactured by Wako Pure Chemical Industries, Ltd.

[Component (F): Antioxidant]
<F-1>
Phenolic Antioxidant / BASF Japan Ilganox® 1010

[Evaluation methods]
The evaluation method of the thermoplastic elastomer composition in the following Examples and Comparative Examples is as follows.

For the following measurements (1) to (4), an in-line screw type injection molding machine (“IS130” manufactured by Toshiba Machine Co., Ltd.) is used under the conditions of an injection pressure of 50 MPa, a cylinder temperature of 220 ° C., and a mold temperature of 40 ° C. A sheet (width 120 mm, length 80 mm, wall thickness 2 mm) obtained by injection molding was used.

(1) Hardness Duro A
According to JIS K6253 (JIS-A), the value was measured 15 seconds after the needle was pressed against the test piece.
The hardness Duro A is preferably in the range of 35 to 95, particularly 40 to 98.

(2) Compressive permanent strain: Measured according to JIS K6262 under the conditions of 70 ° C., 22 hours, and 25% compression.
It was evaluated according to the following criteria from the measured value CS of the compression set (sag).
⊚: CS less than 45% ○: CS 45% or more and less than 51% Δ: CS 51% or more and less than 55% ×: CS 55% or more

(3) Cold resistance (low temperature embrittlement resistance)
The procedure is carried out with reference to the embrittlement temperature test method of JIS K7216.
In JIS K7216, an impact of constant energy is applied to a sheet test piece using an embrittlement tester, and the temperature at which 50% of all sample pieces are brittle fracture is determined. In the present invention, the impact is obtained at −40 ° C. Later, what percentage of all sample pieces remained without breaking was expressed as the unbroken rate, and the cold resistance was evaluated according to the following criteria.
⊚: Unbroken rate 100%
◯: Unbroken rate 60% or more and less than 100% Δ: Unbroken rate 20% or more and less than 60% ×: Unbroken rate 0% or more and less than 20%

(4) Melt flow rate (MFR)
According to JIS K7210, the measurement was performed at 230 ° C. and a measurement load of 49 N.
From the value of MFR, moldability was evaluated according to the following criteria.
◯: MFR less than 1 g (/ 10 minutes)
Δ: MFR 3 g (/ 10 minutes) or more and less than 4 g (/ 10 minutes) ×: MFR 4 g (/ 10 minutes) or more

[Example / Comparative example]
<Example 1>
(A1-1) 20 parts by mass, (A2-1) 6 parts by mass, (B-1) 17 parts by mass, (C-1) 40 parts by mass, (D-1) 17 parts by mass, (E-1) 0.75 parts by mass (mixture of 2,5-dimethyl-2,5-di (t-butylperoxy) hexane 40% by mass and calcium carbonate 60% by mass), (E-2) 0.75 parts by mass (divinyl) A mixture of 60% by mass of benzene and 40% by mass of ethyl vinylbenzene) and 0.1 part by mass of (F-1) were blended with a Henchel mixer for 1 minute to obtain a mixture. This mixture is delivered to the supply section of a isodirectional twin-screw extruder (“TEX30α” manufactured by Japan Steel Works, L / D = 46, number of cylinder blocks: 13) having two raw material supply ports at a total speed of 15 kg / h. The mixture was charged, heated in the range of 110 to 180 ° C., melt-kneaded, and pelletized to produce a thermoplastic elastomer composition.
The evaluation results of the obtained thermoplastic elastomer composition are shown in Table-1.

<Examples 2 to 9 and Comparative Examples 1 to 3>
The same procedure as in Example 1 was carried out except that the compounding composition was changed as shown in Table 1, to obtain pellets of the thermoplastic elastomer composition. Table 1 shows the results of the same evaluation as in Example 1 for the obtained thermoplastic elastomer composition.

<Evaluation result>
As shown in Table 1, Examples 1 to 9 are excellent in the evaluation of "compression permanent strain (sagging property)", "cold resistance (low temperature embrittlement resistance)", and "molding processability (fluidity)".

Comparative Example 1 is an example in which (C-1) used in Example 5 is changed to (c-1), but "compression permanent strain (sagging property)" and "molding processability (fluidity)". The evaluation is inferior.
Further, in Comparative Example 2, the component (C) (C-1) used in Example 5 was divided into the component (B) (B-1) and the component (D) (D-1). This is an example (the effect of removing the component (C) was confirmed), but the evaluation of "molding processability (fluidity)" is inferior.
Comparative Example 3 is an example in which the entire amount (B-1) of the component (B) of Example 5 was distributed to the component (C) (C-1), but "cold resistance (low temperature embrittlement resistance)". ) ”And“ Moldability (fluidity) ”are inferior.

The thermoplastic elastomer composition of the present invention is used for automobile parts such as skins, weather strips, ceiling materials, interior sheets, bumper moldings, side moldings, air spoilers, air duct hoses, sealing materials; water blocking materials, joint materials, window frames, etc. Civil and building material parts such as sealing materials; Sporting goods such as grips for golf clubs and grips for tennis rackets; Industrial parts such as hoses tubes and gaskets; Home appliances parts such as hoses and packings; Medical containers, gaskets, etc. It can be used in a wide range of fields such as medical parts such as packings; food parts such as containers and packings; medical equipment parts; electric wires; miscellaneous goods. Among those listed above, the thermoplastic elastomer composition of the present invention is suitable as a sealing material for automobiles and a sealing material for building materials, and is suitable as a sealing material for automobiles, particularly as a glass run channel for automobiles.

Claims (7)

A thermoplastic elastomer composition obtained by melt-kneading at least the following components (A) to ( D ) and a cross-linking agent.
The ratio of the component (A) to 100 parts by mass of the total amount of the component (A) and the component (B) is 40 to 70 parts by mass, and the ratio of the component (B) is 30 to 60 parts by mass. A thermoplastic elastomer composition having a ratio of 40 to 320 parts by mass with respect to 100 parts by mass of the component (B) .
Component (A): Polypropylene resin component (B): Ethylene / α-olefin copolymer rubber component (C): At least two polymer blocks mainly composed of vinyl aromatic compounds and isoprene as a main component. non-hydrogenated block copolymer having at least one polymer block
Component (D): Hydrocarbon-based rubber softener The thermoplastic elastomer composition according to claim 1, wherein the component (B) is an ethylene / α-olefin / non-conjugated diene copolymer. The thermoplastic elastomer composition according to claim 1 or 2 , wherein the ratio of the cross-linking agent to 100 parts by mass of the total amount of the components (A) to (C) is 0.05 parts by mass or more and 10 parts by mass or less. The thermoplastic elastomer composition according to any one of claims 1 to 3 , wherein the component (A) is a polypropylene-based resin containing the following component (A1) and the component (A2).
Component (A1): The melting peak temperature measured by the following method is 157 ° C. or higher and 175 ° C. or lower. Propylene polymer component (A2): The melting peak temperature measured by the following method is 100 ° C. or higher and lower than 157 ° C. Propylene-based random copolymer
<Measurement method of melting peak temperature>
Using a differential scanning calorimeter according to JIS K7121, the following steps (1) to (3) are carried out in order to measure the melting behavior of the polypropylene resin. In each process, time is plotted on the horizontal axis and heat of fusion is plotted on the vertical axis to obtain a melting curve, and the peak peak of the peak observed in step (3) is defined as the melting peak temperature.
Step (1): The temperature of 5 mg of the sample is raised from room temperature to 40 ° C. to 200 ° C. at a rate of 100 ° C./min.
After the temperature rise is completed, it is held for 3 minutes.
Step (2): Lower the temperature from 200 ° C to 40 ° C at a rate of 10 ° C / min, and hold for 3 minutes after the temperature reduction is completed.
To do.
Step (3): The temperature is raised from 40 ° C. to 200 ° C. at a rate of 10 ° C./min. A molded product using the thermoplastic elastomer composition according to any one of claims 1 to 4. The molded product according to claim 5 , which is a member for an automobile. The molded product according to claim 6 , which is a glass run channel for automobiles.