JP2001049051A - Thermoplastic elastomer composition and its molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of giving a molded product which is excellent in flexibility and does not glaze when heated by compounding a polyolefinic resin and a hydrogenated diene-based copolymer each in a specific amount. SOLUTION: The resin composition comprises 100 pts.wt. of a polyolefinic resin (A), 10-1,000 pts.wt. of a hydrogenated diene-based copolymer (B) and further not more than 250 pts.wt. of an ethylene/α-olefin-based copolymer, and the like. The ingredient B comprises a vinyl aromatic compound polymer block (M) and a hydrogenated block (N). The total content (T) of the vinyl aromatic compound units in the ingredient B is 10-18 wt.%. The ratio (S) of the content of the vinyl aromatic compound units in the ingredient M to the total vinyl aromatic compound unit content is at least 3%. The ratio (V) of the number of hydrogenated conjugated diene units having a 2C or higher side chain to the number of all hydrogenated conjugated diene units is at least 60%. T, S and V satisfy the relation represented by the equation: V<=0.375×S+1.25×T+40. The hydrogenation rate of double bonds in the conjugated diene units is at least 80% and the number-average mol.wt. of the ingredient B is 50,000-600,000.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic elastomer composition and a molded article comprising the composition. More specifically, the present invention contains a polyolefin-based resin and a hydrogenated diene-based copolymer having a specific structure as essential components, has excellent flexibility, and is heated to a temperature of about 80 ° C. to less than the melting point of the polyolefin-based resin. The present invention relates to a thermoplastic elastomer composition capable of providing a molded article which does not emit gloss even when the composition is produced, and a molded article thereof.

[0002]

2. Description of the Related Art Conventionally, vinyl chloride resins have been widely used for interior and exterior parts of automobiles, household appliances, stationery, office automation equipment, packaging containers, sports goods and the like. However, due to global environmental problems and the like, substitution of vinyl chloride resins has been promoted, and as an alternative, a thermoplastic elastomer composition containing a polyolefin resin and a styrene thermoplastic elastomer has been proposed (for example, And JP-A-3-72512.

JP-A-3-72512 describes a hydrogenated diene copolymer composition comprising a nonpolar resin such as polypropylene and a hydrogenated diene copolymer having a specific structure. The molded article made of the composition is excellent in flexibility. However, since the molded article made of the hydrogenated diene copolymer composition of the present invention emits gloss when heated at a temperature of about 80 ° C. to a temperature lower than the melting point of the polyolefin resin, it has poor appearance when used outdoors. (For example, it is known that when used outdoors, the temperature of the surface of the molded body rises to about 80 to 120 ° C.).

[0004]

Under such circumstances, the problem to be solved by the present invention is to contain a polyolefin-based resin and a specific hydrogenated diene-based copolymer as essential components and have excellent flexibility. It is still another object of the present invention to provide a thermoplastic elastomer composition capable of providing a molded article that does not emit gloss when heated at a temperature of about 80 ° C. to less than the melting point of the polyolefin resin, and a molded article thereof.

[0005]

Means for Solving the Problems That is, according to the present invention,
The first invention comprises the following (a) 100 parts by weight and (b) 10 parts by weight.
Thermoplastic elastomer composition containing -1000 parts by weight
It relates to things. (A): Polyolefin resin (B): Hydrogenated die that satisfies all of the following conditions
-Based copolymer: The hydrogenated diene-based copolymer has the following structure (A) or (B):
(A): vinyl aromatic compound polymer block (B): selected from the following (B1), (B2) and (B3)
(B1): random of vinyl aromatic compound and conjugated diene
A block obtained by hydrogenating a copolymer block (B2): a block composed of a vinyl aromatic compound and a conjugated diene.
Tapered block with gradually increasing vinyl aromatic compound
Is a hydrogenated block (B3): a conjugated diene polymer block is hydrogenated
Block: Totally vinyl aromatic contained in hydrogenated diene copolymer
The compound unit content (T) is 10 to 18% by weight: all vinyl aromatic compounds in the hydrogenated diene copolymer
Vinyl aromatic compound of the above (A) with respect to the content of
The unit content ratio (S: percentage) is 3% or more: all hydrogenated conjugated dienes in the hydrogenated diene copolymer
Hydrogenated having side chains with 2 or more carbon atoms per unit number
The ratio of the number of conjugated diene units (V: percentage) exceeds 60%
That  : The above (T) in the hydrogenated diene copolymer and the above
The relationship between (S) and (V) is expressed by the following equation (1).
V ≦ 0.375 × S + 1.25 × T + 40 (1): Concentration of conjugated diene units in the hydrogenated diene copolymer
80% or more of the double bonds are hydrogenated: the number average molecular weight of the hydrogenated diene copolymer is 50,000 to 60
Further, the second invention of the present invention is the heat of the first invention.
Pertaining to a molded article made of a thermoplastic elastomer composition
is there.

[0006]

DETAILED DESCRIPTION OF THE INVENTION The component (A) of the present invention is a polyolefin resin, and is at least one selected from homopolymers or copolymers of olefins having high crystallinity. As the olefin, ethylene, propylene,
Examples thereof include olefins having 2 to 8 carbon atoms such as 1-butene, 1-hexene and 1-octene. Examples of (a) include polyethylene, polypropylene, poly (1-butene), copolymers of propylene and ethylene, copolymers of propylene and other α-olefins (eg, 1-butene) and the like. Is raised. When (a) is a propylene-ethylene copolymer resin or a propylene-1-butene copolymer resin, the thermoplastic elastomer composition of the present invention can provide a molded article having excellent heat resistance and flexibility. It is preferred in that respect. The crystallinity of (a) needs to be 50% or more, and preferably 60% or more. Here, the crystallinity refers to the crystallinity of only the olefin unit having the highest weight content in the resin used and produced under the same conditions (temperature, pressure, amount of catalyst, etc.) using the same catalyst system. The ratio of the heat of fusion of (a) to the heat of fusion of the polyolefin homopolymer is shown. The heat of fusion is D
It is determined by the SC method.

Further, a copolymer obtained by copolymerizing two or more monomers selected from ethylene and an α-olefin having 3 to 8 carbon atoms in two or more steps can be used. For example, a copolymer obtained by homopolymerizing propylene in the first step and copolymerizing propylene with ethylene or an α-olefin other than propylene in the second step can be used.

From the viewpoint of the strength of the molded article made of the thermoplastic elastomer of the present invention, JIS K-7 (A)
The melt flow rate (MFR) measured at 230 ° C. under a load of 2.16 kgf in accordance with No. 210 is usually 0.1 to
It is in the range of 500 g / 10 min, preferably 1 to 300 g / 10 min.

The component (b) of the present invention is a hydrogenated diene copolymer which satisfies all of the above conditions.

Examples of the conjugated diene used in the production of (b) include, for example, 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), 1,3-pentadiene, and 2,3-dimethyl-diene. 1,3-butadiene, 2-
4-8 carbon atoms such as methyl-1,3-pentadiene
Conjugated dienes. Among them, 1,3-butadiene and isoprene are preferred because they can be easily used industrially and a hydrogenated diene copolymer excellent in physical properties can be obtained.

The vinyl aromatic compound has one of the vinyl groups.
The 2- or 3-position may be substituted with an alkyl group such as a methyl group. Examples of vinyl aromatic compounds include styrene, p-methylstyrene, α-methylstyrene, t-
Examples thereof include vinyl aromatic compounds having 8 to 12 carbon atoms, such as butylstyrene, divinylbenzene, and vinylpyridine. Among them, styrene is preferably used from an industrial viewpoint.

(B) is a hydrogenated diene copolymer containing the following structural units (A) and (B). (A): vinyl aromatic compound polymer block (B): at least one type of block selected from the following (B1), (B2) and (B3) (B1): random copolymerization of vinyl aromatic compound and conjugated diene Block (B2): a block formed by hydrogenation of a vinyl aromatic compound and a conjugated diene, and a block formed by hydrogenating a tapered block in which a vinyl aromatic compound is gradually increased (B3): a conjugated diene polymer block Is hydrogenated block

(B) is usually represented by the general formula [(A)-(B)]
n, [(A)-(B)] n- (A), [(B)-
(A)] n- (B) (where n is an integer of 1 or more;
When there are a plurality of (A) and (B), each of the plurality of (A) and (B) may be the same or different. ), For example, [(A)-(B
1)] n- (A), [(A)-(B2)] n- (A),
Or [(A)-(B3)] n- (A) (where n is an integer of 1 or more and repeating units (A), (B1) and (B2)
And (B3) may be the same or different. And hydrogenated diene copolymers represented by

Among them, (A)-(B1)-(A),
(A)-(B2)-(A) or (A)-(B3)-
The hydrogenated diene copolymer represented by (A) is preferable in that it is industrially easy to produce, and is preferably a hydrogenated product of a styrene-butadiene / styrene-styrene copolymer or a water-soluble styrene-butadiene-styrene copolymer. Hydrogenated product of styrene-isoprene-styrene-styrene copolymer, styrene-
Hydrogenated isoprene-styrene copolymers are preferred in that they can be industrially easily produced. In particular, a hydrogenated product of a styrene-butadiene-styrene copolymer is excellent in the strength and cold impact resistance of the obtained molded product, and the strength of the obtained molded product is the same as that of the hydrogenated diene-based copolymer described below. Even if there is a subtle “run-out” in the production, the ratio (V: percentage) of the number of hydrogenated conjugated diene units having a side chain having 2 or more carbon atoms to the number of all conjugated diene units added, It is preferable in that it is hardly affected. Note that "-" indicates a boundary between blocks, and "-" indicates that two or more compounds are used in combination in one block.

The total content of the vinyl aromatic compound unit in (b) must be in the range of 10 to 18% by weight (conditions), and is preferably in the range of 12 to 17% by weight. Total vinyl aromatic compound unit content is 18
If the amount is more than 10% by weight, a molded article obtained by molding the thermoplastic elastomer composition tends to be hard. Further, when the total vinyl aromatic compound unit content is less than 10% by weight,
There is a problem that the obtained molded article has tackiness. The total vinyl aromatic compound unit content can be determined by ¹ H-NMR measurement at a frequency of 90 MHz or more, using the solution (b) of carbon tetrachloride or the like.

The ratio (S: percentage) of the vinyl aromatic compound unit content of the vinyl aromatic compound polymer block (A) to the total vinyl aromatic compound unit content of (b) is as follows:
3% or more (condition) is required, and 30 to 1
It is preferably 00%, more preferably 50 to 100%. If the proportion is less than 3%, there is a problem that the obtained molded article has tackiness. The ratio was determined by using a solution of the carbon tetrachloride (b) in 90 MH
It can be determined by ¹ H-NMR measurement at a frequency of z or more.

In (b), the ratio of the number of hydrogenated conjugated diene units having a side chain having 2 or more carbon atoms to the number of all hydrogenated conjugated diene units of the conjugated diene copolymer (V: percentage ) Needs to be 60% or more (conditions), and is preferably 60 to 85%, and particularly preferably 65 to 80%. The ratio is 60
%, The obtained molded body becomes hard. In addition, such a ratio can be obtained by a Morello method using infrared analysis.

(B) Total vinyl aromatic compound unit content (T), (A) Ratio of vinyl aromatic compound unit content of vinyl aromatic compound polymer block to total vinyl aromatic compound unit content (S : Percentage) and the ratio (V: percentage) of the number of hydrogenated conjugated diene units having a side chain having 2 or more carbon atoms to the number of all hydrogenated conjugated diene units of the hydrogenated diene copolymer. It is necessary that the relationship be represented by the following equation (1) (condition). V ≦ 0.375 × S + 1.25 × T + 40 (1) In the expression (1), when the value on the left side exceeds the value on the right side,
When the obtained molded body is heated at a temperature of about 80 ° C. to less than the melting point of the polyolefin-based resin, the molded body has a problem that it emits gloss.

It is necessary that 80% or more of the double bonds of the conjugated diene unit in (b) be hydrogenated (conditions), and 90% or more, particularly 96% or more be hydrogenated. preferable. When the degree of hydrogenation is less than 80%, there is a problem that the light resistance of the obtained molded article is reduced.

It is necessary that the number average molecular weight of (b) is from 50,000 to 600,000 (conditions) in order to obtain a molded article excellent in appearance and strength, and it is in the range of from 100,000 to 500,000. preferable. If the number average molecular weight is less than 50,000, the resulting molded article will have tackiness and insufficient heat resistance and light resistance. When the number average molecular weight exceeds 600,000, the meltability of the thermoplastic elastomer composition of the present invention is poor, so that a molded article having a sufficient appearance and strength cannot be obtained. The number average molecular weight is measured by a GPC method.

The melt flow rate (MFR) measured at 230 ° C. under a load of 2.16 kgf in accordance with JIS K-7210 (b) is preferably 0.1 to 200 g / 10 min, and more preferably 1 to 100 g / min. 10 minutes, particularly preferably 3
It is preferable that it is ８０80 g / 10 minutes in that a molded article having a sufficient appearance and strength can be obtained.

The compound (b) of the present invention may be modified with a functional group and has at least one functional group selected from an acid anhydride group, a carboxyl group, a hydroxyl group, an amino group, an isocyanate group and an epoxy group. Modified functional groups can also be used. When these are used, for example, when the obtained molded article is bonded to a polyurethane foam layer to produce a two-layer molded article or a multilayer molded article, it is possible to obtain an advantage that the adhesiveness is improved.

Such hydrogenated diene copolymers are disclosed, for example, in JP-A-3-72512 and JP-A-5-2713.
No. 25, JP-A-5-271327, JP-A-6-271327
It can be produced by a method described in -287365 or the like.

The thermoplastic elastomer composition of the present invention comprises:
In addition to the essential components (a) and (b), (c) an ethylene-α-olefin copolymer may be contained.
When (c) is contained, the thermoplastic elastomer composition of the present invention can be obtained without deteriorating the moldability, flexibility and non-glossiness of the thermoplastic elastomer and having excellent cold impact resistance.

(C) The ethylene-α-olefin copolymer is a copolymer of ethylene and α-olefin, a copolymer of ethylene, α-olefin and non-conjugated diene, and has almost no crystallinity. A polymer having no or a crystallinity of less than 50%. Here, the crystallinity means the ratio of the heat of fusion of a polyethylene homopolymer to the heat of fusion of a polyethylene homopolymer produced under the same conditions (temperature, pressure, amount of catalyst used, etc.) using the same catalyst system. Show. The heat of fusion is determined by the DSC method. Here, as the α-olefin, propylene, 1-butene, 3-methyl-1-
Α-olefin having 3 to 10 carbon atoms such as butene,
As the non-conjugated diene, dicyclopentadiene, 5-2
Ethylidene norbornene, 1,4-hexadiene, 1,
Examples thereof include non-conjugated dienes having 5 to 15 carbon atoms such as 5-cyclooctadiene and 5-methylene-2-norbornene. Examples of the ethylene-α-olefin-based copolymer include ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, and ethylene-propylene- 5-ethylidene 2-norbornene copolymer (hereinafter referred to as “EPDM”). Such an ethylene-α-olefin-based copolymer may be crosslinked.

The α-olefin unit content in (c) is
Preferably 5 to 40% by weight, more preferably 10 to 35%
Wt% and the ethylene unit content is usually 6%.
0 to 95% by weight, preferably 65 to 90% by weight.
α-olefin unit content and ethylene unit content,
It can be determined by ¹³ C-NMR method, infrared absorption spectroscopy, or the like. In addition, from the viewpoint of the strength of a molded product obtained by molding the thermoplastic elastomer composition of the present invention, ASTM of this ethylene-α-olefin-based copolymer is used.
The Mooney viscosity {ML 1 _{+ 4} (100 ° C.)} measured at 100 ° C. according to D-927-57T is preferably 10 to 3
50, more preferably in the range of 15 to 300.

When (c) is used, the amount of (c) is
(A) 250 parts by weight or less for 100 parts by weight;
Preferably it is 20 to 200 parts by weight. If the amount of (c) is excessive, the resulting molded article may have a sticky feeling.

The thermoplastic elastomer composition of the present invention further comprises, in addition to the essential components (a) and (b),
(D) A styrene-based thermoplastic elastomer other than the above (b) may be contained. Examples of (d) include, for example, hydrogenated diene-based copolymers containing the same structural units (A) and (B) as described in (b) above, and hydrogenated vinyl aromatic compound-conjugated diene random copolymers. Things and the like. (D)
As a hydrogenated diene-based copolymer containing the same structural units (A) and (B) as described in (b) above, hydrogenated diene that does not satisfy at least one of the conditions described in (b) above System copolymers.

For example, when the conditions are not satisfied, and a hydrogenated diene copolymer satisfying and is used (when the relational expression of V> 0.375 × S + 1.25 × T + 40 is satisfied), Provides a thermoplastic elastomer composition having better scratch resistance.

When a hydrogenated diene copolymer which does not satisfy the conditions is used (water having a side chain having 2 or more carbon atoms with respect to the total number of hydrogenated conjugated diene units in the hydrogenated diene copolymer) is used. When a hydrogenated diene copolymer having a ratio of the number of added conjugated diene units (V: percentage) of 60% or less is used, a thermoplastic elastomer composition having more excellent cold impact resistance is provided.

When (d) is used, the amount of (d) is
(A) 250 parts by weight or less for 100 parts by weight;
Preferably it is 20 to 200 parts by weight. If the amount of (d) is excessive, for example, the obtained molded product may have a sticky feeling.

The thermoplastic elastomer composition of the present invention comprises:
In addition to the essential components (a) and (b), a hydrogenated product of (e) a conjugated diene polymer may be contained. Examples of (e) include hydrogenated polybutadiene and hydrogenated polyisoprene. In (e), the ratio (V: percentage) of the number of hydrogenated conjugated diene units having a side chain having 2 or more carbon atoms to the total number of hydrogenated conjugated diene units is 60%.
It is preferable that the ratio exceeds 2 from the viewpoint of the flexibility of the obtained molded body, but the hydrogenated diene polymer may be composed of two or more blocks having different ratios. Examples of such a hydrogenated diene polymer include a polymer described in JP-A-3-74409 and CEBC6200 manufactured by JSR Corporation.
And the like. When (e) is added to the thermoplastic elastomer composition of the present invention, the strength of the obtained molded article is improved (particularly when the thermoplastic elastomer composition contains (c)).

When (e) is used, the amount of (e) is
(A) 250 parts by weight or less for 100 parts by weight;
Preferably it is 2 to 200 parts by weight. If the amount of (e) is excessive, the resulting molded article may have a sticky feeling.

The thermoplastic elastomer composition of the present invention comprises:
Rubbery polymers such as natural rubber, butyl rubber, chloroprene rubber, epichlorohydrin rubber, acrylic rubber, ethylene-acrylic acid copolymer, ethylene-vinyl acetate copolymer and saponified product thereof, ethylene-methyl methacrylate copolymer And other polymer components such as ethylene-glycidyl acrylate-vinyl acetate copolymer and ethylene-glycidyl methacrylate-vinyl acetate copolymer.

The thermoplastic elastomer composition of the present invention comprises:
For example, mineral oil-based softeners, heat stabilizers such as phenol-based, sulfite-based, phenylalkane-based, phosphite-based, amine-based, and amide-based, weather-resistant stabilizers, antistatic agents, pigments, metallic soaps, waxes, Fungicides, antibacterial agents,
Various additives such as a filler may be contained.

When the thermoplastic elastomer composition of the present invention contains a mineral oil-based softening agent, a molded article comprising the thermoplastic elastomer composition having excellent melting properties and flexibility can be obtained.

When the thermoplastic elastomer composition of the present invention contains a pigment, it is possible to obtain a molded article which is hardly discolored even when wiped with an organic solvent such as hexane, benzene or toluene. Examples of pigments include organic pigments such as azo-based, phthalocyanine-based, sulene-based and dye lakes, oxides such as titanium oxide, molybdic acid chromate, selenium sulfide compounds, ferrocyanide compounds, and inorganic pigments such as carbon black. Used.

As the pigment, any of a liquid substance and a powdery substance can be used. When a powdery pigment is used, a pigment supported on a carrier such as calcium carbonate, metal soap, or magnesium oxide can also be used. In this case, the primary particle size of the carrier is usually 10 μm or less, preferably 1 μm or less.
５5 μm. In this case, the weight ratio of the powder pigment to the carrier is usually 20:80 to 80:20, preferably 25: 7.
5 to 75:25.

The thermoplastic elastomer composition for powder molding of the present invention contains the above (a) and (b) as essential components, and if necessary, at least one of (c), (d) and (e) Contains one kind. The content of (b) is (a) 1
It is necessary that (b) be contained in an amount of 10 to 1000 parts by weight, preferably 40 to 200 parts by weight, based on 00 parts by weight. (B) When the content of (b) is less than 10 parts by weight with respect to 100 parts by weight, the flexibility of the obtained molded article is inferior, and when it exceeds 1000 parts by weight, the obtained molded article has tackiness. In addition, heat resistance and light resistance become insufficient.

The M of the thermoplastic elastomer composition of the present invention
FR is from 0.1 to 200 g / 1 from the viewpoint of moldability of the thermoplastic elastomer composition and appearance of the obtained molded article.
0 minutes, more preferably 0.5 to 100 g /
Preferably, it is 10 minutes.

Examples of the method for obtaining the thermoplastic elastomer composition of the present invention include the following methods. That is, at least one of (a) and (b) and (c), (d) and (e) blended as necessary may be melt-kneaded. Alternatively, it can be produced by kneading or dynamically cross-linking all or some of the above-mentioned components and then kneading and kneading the unselected components. For example, (a), (b),
The thermoplastic elastomer composition of the present invention containing (c), (d) and (e), wherein (a) and / or (c) is cross-linked intramolecularly and / or intermolecularly, usually comprises ( After dynamically cross-linking (a) and (c), (b), (d) and (e) can be further added and kneaded. Here, for kneading, a single-screw extruder, a twin-screw extruder, a kneader, a roll, or the like can be used. The above-mentioned various additives and various polymers are compounded, for example, by mixing these additives in advance (a), (b), (c),
It can be carried out by using (d) or (e), or by mixing the above components during kneading or dynamic crosslinking.

The dynamic crosslinking of the kneaded mixture can be performed, for example, by kneading the kneaded mixture and a crosslinking agent under heating. As the crosslinking agent, usually, 2,5-dimethyl-2,5-di (tert-butylperoxyno) is used.
Organic peroxides such as hexane and dicumyl peroxide are used. The crosslinking agent is subjected to crosslinking (a) and (b) and optionally blended (c) and (d).
Per 100 parts by weight of at least one of
Usually, it is used in an amount of 1 part by weight or less, preferably 0.1 to 0.8 part by weight, more preferably 0.2 to 0.6 part by weight. When using an organic peroxide as a crosslinking agent,
When dynamic crosslinking is performed in the presence of a crosslinking assistant such as a bismaleimide compound, a thermoplastic elastomer composition that gives a molded article having excellent heat resistance can be obtained. In this case, the used amount of the organic peroxide is subjected to crosslinking (A),
(B) and, if necessary, at least one of (c), (d) and (e), usually 0.8 weight per 100 parts by weight of the total of the components to be crosslinked. Parts by weight, preferably 0.2 to 0.8 parts by weight, more preferably 0.4 to 0.6 parts by weight.

The amount of the cross-linking aid used is (a) and (b) to be cross-linked and, if necessary, (c)
And usually at most 1.5 parts by weight, preferably at most 0.2 parts by weight, per 100 parts by weight of at least one of (d) and (d).
To 1 part by weight, more preferably 0.4 to 0.8 part by weight. The crosslinking aid is preferably added before the addition of the crosslinking agent, and is usually added when the components to be crosslinked are preliminarily kneaded. Crosslinking can be performed by kneading under heating using, for example, a single-screw extruder or a twin-screw extruder in a temperature range of 150 to 250 ° C. Also,
Crosslinking can be performed by a method such as sulfur crosslinking.

These additives and other polymer components are:
(I) and (b) and if necessary, (c), (d) and (e) may be used by being contained in advance in at least one of them. Alternatively, it may be blended by kneading or the like.

When a mineral oil-based softener is used, the oil-extended ethylene-α in which the mineral oil-based softener is previously contained in (c) is used.
When the olefin copolymer is used, the above-described kneading and dynamic crosslinking can be easily performed.

In order to produce the thermoplastic elastomer composition of the present invention, the above-mentioned kneading and the degree of dynamic cross-linking are performed.
The type and amount of each component constituting the thermoplastic elastomer composition, the type and amount of a crosslinking agent or a cross-linking aid in dynamic crosslinking, the type of additive and the amount thereof are appropriately selected. Among them, the shear rate in kneading and dynamic crosslinking has a large effect on the above physical properties, and the shear rate is 1 × 10 ³
It is preferred that kneading or dynamic crosslinking be performed in seconds ⁻¹ or more.

The thermoplastic elastomer composition of the present invention comprises:
A molded article having a desired shape can be produced by a method such as an injection molding method, an extrusion molding method, a vacuum molding method, and a compression molding method. The molding temperature in these moldings is not problematic as long as it is a temperature equal to or higher than the melting point of the polyolefin resin, but is usually in the range of 160 to 320 ° C, preferably 180 to 300 ° C.

It is to be noted that a foamed molded article can be produced by molding the thermoplastic elastomer composition of the present invention containing a foaming agent, followed by foaming. In this case, it is preferable that the foaming agent is previously contained in the thermoplastic elastomer composition. As the foaming agent, a pyrolytic foaming agent is usually used. Examples of such a pyrolytic foaming agent include azo compounds such as azodicarbonamide, 2,2'-azobisisobutyronitrile, and diazodiaminobenzene, benzenesulfonyl hydrazide, benzene-1,3-sulfonyl hydrazide, p- Sulfonyl hydrazide compounds such as toluenesulfonyl hydrazide; nitroso compounds such as N, N'-dinitrosopentamethylenetetramine, N, N'-dinitroso-N, N'-dimethylterephthalamide; azide compounds such as terephthalazide; sodium bicarbonate And carbonates such as ammonium bicarbonate and ammonium carbonate. Among them, azodicarbonamide is preferably used. The compounding of the blowing agent is usually performed at a temperature equal to or lower than the decomposition temperature of the blowing agent. Further, a foaming aid and a cell conditioner may be contained together with the foaming agent.

The molded article comprising the thermoplastic elastomer composition of the present invention is useful as a non-foamed material, but can also be used as a two-layer molded article in which a foam layer is laminated on one side, The molded article or the two-layer molded article is a multilayer molded article obtained by laminating a thermoplastic resin core material on one surface side (in the case of a two-layer molded article composed of a non-foamed layer and a foamed layer, the foamed layer side). It can also be used.

[0050]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. [1] Determined by ¹ H-NMR measurement (frequency: 90 MHz) using a carbon tetrachloride solution having a total vinyl aromatic compound unit content of (b) in (b). [2] Ratio of the content of the vinyl aromatic compound in the vinyl aromatic compound polymer block (A) to the total content of the vinyl aromatic compound in the hydrogenated diene copolymer in (b) (S) (b) Was determined by ¹ H-NMR measurement (frequency: 90 MHz) using a carbon tetrachloride solution of [3] Ratio of the number of hydrogenated conjugated diene units having side chains having 2 or more carbon atoms to the number of all hydrogenated conjugated diene units in (b) (V) Morero method using infrared analysis Determined by [4] Hydrogenation rate of double bond of conjugated diene unit in hydrogenated diene copolymer was determined by ¹ H-NMR measurement (frequency: 90 MHz) using a carbon tetrachloride solution of (b). [5] Gel Permeation Chromatography (GP) at 38 ° C. using a tetrahydrofuran solution of (b) number average molecular weight (b)
It was determined as a polystyrene equivalent value by the method C). [6] Flexibility of molded article of thermoplastic elastomer composition The hardness of the thermoplastic elastomer produced in the following examples was measured according to JIS K6301. [7] Change in appearance when a molded article made of a thermoplastic elastomer composition is heated A molded sheet having a thickness of 1 mm obtained by a compression molding method described below is used as a gear oven (Yamato Kagaku Co., Ltd.) (A semi-explosion-proof dryer manufactured by the company) for 24 hours, and the change in gloss value (gloss) before and after heating was determined based on the following criteria. The gloss value was measured using a digital gloss meter (GM-26D, manufactured by Murakami Color Research Laboratory, reflection angle 60 °). ：: Difference in gloss value is less than 1.0 △: Difference in gloss value is 1.0 or more and less than 2.5 ×: Difference in gloss value is 2.5 or more

Example 1 Propylene-ethylene copolymer resin [manufactured by Sumitomo Chemical Co., Ltd., ethylene unit content 5% by weight, MFR = 20 g]
/ 10 min], 100 parts by weight, hydrogenated styrene-butadiene-styrene-styrene copolymer [(A)-(B1)-
(A) Corresponding to the structure, the total styrene unit content is 16% by weight,
Hydrogenated having a vinyl aromatic compound unit content of 85% of (A) part based on the total styrene unit content, MFR = 10 g / 10 min, and a side chain having 2 or more carbon atoms with respect to all hydrogenated conjugated diene units. The proportion of the conjugated diene unit is 75%, the hydrogenation rate is 98%, the number average molecular weight is 130,000], 100 parts by weight, and 1 part by weight of the black pigment carbon black is monoaxial with respect to 100 parts by weight of the propylene-ethylene copolymer resin. Using a kneader (VS40 mm extruder, manufactured by Tanabe Plastic Machinery Co., Ltd.), the composition was kneaded at a temperature of 170 ° C. to obtain a composition, which was cut using a cutter to obtain pellets. The pellets were pre-heated at 170 ° C. and 30 kgf / cm ² using a press forming machine [PESW-5040 manufactured by Kansai Roll Co., Ltd.] in a grain pattern mold, and then 150 kgf.
/ Cm ² to obtain a molded article of a thermoplastic elastomer composition having a grain pattern (thickness: 1 mm). Tables 1 and 2 show the evaluation results of the molded body.

Example 2 Total styrene unit content: 10% by weight, vinyl aromatic compound unit content in part (A) to total styrene unit content: 8
0%, MFR = 15 g / 10 min, ratio of hydrogenated conjugated diene unit having a side chain having 2 or more carbon atoms to hydrogenated conjugated diene unit is 70%, hydrogenation rate 98%, number average molecular weight Styrene-butadiene-styrene of 160,000
Hydrogenated styrene copolymer ((A)-(B1)-(A)
A molded article was obtained in the same manner as in Example 1, except that the corresponding structure was used. Table 1 shows the evaluation results.

Example 3 Total styrene unit content: 15% by weight, vinyl aromatic compound unit content in part (A) to total styrene unit content: 8
0%, MFR = 34 g / 10 min, ratio of hydrogenated conjugated diene unit having a side chain having 2 or more carbon atoms to hydrogenated conjugated diene unit is 75%, hydrogenation rate 98%, number average molecular weight 120,000 styrene-butadiene-styrene-
Hydrogenated styrene copolymer ((A)-(B1)-(A)
A molded article was obtained in the same manner as in Example 1, except that the corresponding structure was used. The evaluation results are shown in Tables 1 and 2.

Example 4 The total styrene unit content was 15% by weight, and the vinyl aromatic compound unit content of part (A) was 1 based on the total styrene unit content.
00%, MFR = 31 g / 10 min, ratio of hydrogenated conjugated diene units having a side chain having 2 or more carbon atoms to all hydrogenated conjugated diene units is 79%, hydrogenation rate 98%, number average molecular weight Except for using a hydrogenated styrene-butadiene-styrene copolymer (corresponding to the structure (A)-(B3)-(A)) of 120,000, the same procedure as in Example 1 was carried out to obtain a molded article. Obtained. Table 1 shows the evaluation results.

Comparative Example 1 Total styrene unit content: 10% by weight, vinyl aromatic compound unit content of part (A) to total styrene unit content: 4
0%, MFR = 10 g / 10 min, ratio of hydrogenated conjugated diene units having side chains having 2 or more carbon atoms to all hydrogenated conjugated diene units is 80%, hydrogenation rate 98%, number average molecular weight 200,000 styrene-butadiene-styrene-
Hydrogenated styrene copolymer ((A)-(B1)-(A)
A molded article was obtained in the same manner as in Example 1, except that the corresponding structure was used. The evaluation results are shown in Tables 1 and 2.

Comparative Example 2 Total styrene unit content 19% by weight, vinyl aromatic compound unit content 1 in part (A) based on total styrene unit content 1
00%, MFR = 30 g / 10 min, ratio of hydrogenated conjugated diene units having side chains having 2 or more carbon atoms to all hydrogenated conjugated diene units is 42%, hydrogenation rate 98%, number average molecular weight 12,000 hydrogenated styrene-butadiene-styrene-styrene copolymer ((A)-(B3)-
A molded product was obtained in the same manner as in Example 1, except that (A) corresponding to the structure) was used. The evaluation results are shown in Tables 1 and 2.

Comparative Example 3 Total styrene unit content: 14% by weight, vinyl aromatic compound unit content in part (A) to total styrene unit content: 4
5%, MFR = 11 g / 10 min, ratio of hydrogenated conjugated diene units having side chains having 2 or more carbon atoms to hydrogenated conjugated diene units is 78%, hydrogenation rate 98%, number average molecular weight 200,000 styrene-butadiene-styrene-
Hydrogenated styrene copolymer ((A)-(B1)-(A)
A molded article was obtained in the same manner as in Example 1, except that the corresponding structure was used. The evaluation results are shown in Tables 1 and 2.

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[Table 1] (b) Hydrogenated diene copolymer

[0059]

[Table 2] Evaluation results of molded articles of thermoplastic elastomer composition

Example 5 In Example 1, 100 parts by weight of propylene-ethylene copolymer resin [manufactured by Sumitomo Chemical Co., Ltd., ethylene unit content 5% by weight, MFR = 20 g / 10 minutes], styrene-butadiene-styrene Hydrogenated copolymer [(A)-
Corresponds to (B3)-(A) structure, total styrene unit content 1
5% by weight, 100% vinyl aromatic compound unit content in part (A) based on total styrene unit content, MFR = 30 g
/ 10 minutes, the ratio of the hydrogenated conjugated diene unit having a side chain having 2 or more carbon atoms to all hydrogenated conjugated diene units is 80%, the hydrogenation rate is 98%, and the number average molecular weight is 130,000] 100
Parts by weight, ethylene-propylene copolymer rubber [manufactured by Sumitomo Chemical Co., Ltd., Esplen V0141, propylene unit content 27% by weight, MFR = 0.7 g / 10 min] 50
A molded article was obtained according to Example 1, except that 2.5 parts by weight of black pigment carbon black and 2.5 parts by weight of black pigment were used. Tables 3 and 4 show the evaluation results of the molded product.

[0061]

[Table 3] (b) Hydrogenated diene copolymer

[0062]

[Table 4] Evaluation results of molded articles of thermoplastic elastomer composition

[0063]

As described above, according to the present invention, a polyolefin resin and a hydrogenated diene copolymer having a specific structure are contained as essential components, excellent in flexibility and 80 ° C.
It was possible to provide a molded article which does not emit gloss even when heated to a temperature lower than the melting point of the polyolefin-based resin, and a thermoplastic elastomer composition capable of providing the molded article.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroki Nakajima 2-11-24 Tsukiji, Chuo-ku, Tokyo Inside JSR Co., Ltd. (72) Inventor Hiroyuki Sugimoto 5-1, Anesaki Beach, Ichihara-shi, Chiba Sumitomo Chemical (72) Inventor Yoshihiro Nakatsuji 5-1, Anesaki Beach, Ichihara City, Chiba Prefecture F-term (reference) 4F071 AA12X AA14 AA15X AA20X AA21X AA22X AA75 AH04 AH07 AH12 BA01 BB03 BB05 BB06 BC01 4B002 BB12X BB14X BB15X BB17X BP01W GF00 GG02 GN00 GQ00 4J026 HD05 HD14 HD15 HE01 HE02

Claims (5)

[Claims] 1. The following (A) 100 parts by weight and (B) 10
Thermoplastic elastomer composition containing -1000 parts by weight
object. (A): Polyolefin resin (B): Hydrogenated die that satisfies all of the following conditions
-Based copolymer: The hydrogenated diene-based copolymer has the following structure (A) or (B):
(A): vinyl aromatic compound polymer block (B): selected from the following (B1), (B2) and (B3)
(B1): random of vinyl aromatic compound and conjugated diene
A block obtained by hydrogenating a copolymer block (B2): a block composed of a vinyl aromatic compound and a conjugated diene.
Tapered block with gradually increasing vinyl aromatic compound
Is a hydrogenated block (B3): a conjugated diene polymer block is hydrogenated
Block: Totally vinyl aromatic contained in hydrogenated diene copolymer
The compound unit content (T) is 10 to 18% by weight: all vinyl aromatic compounds in the hydrogenated diene copolymer
Vinyl aromatic compound of the above (A) with respect to the content of
The unit content ratio (S: percentage) is 3% or more: all hydrogenated conjugated dienes in the hydrogenated diene copolymer
Hydrogenated having side chains with 2 or more carbon atoms per unit number
The ratio of the number of conjugated diene units (V: percentage) exceeds 60%
That  : The above (T) in the hydrogenated diene copolymer and the above
The relationship between (S) and (V) is expressed by the following equation (1).
V ≦ 0.375 × S + 1.25 × T + 40 (1): Concentration of conjugated diene units in the hydrogenated diene copolymer
80% or more of the double bonds are hydrogenated: the number average molecular weight of the hydrogenated diene copolymer is 50,000 to 60
Be all 2. A method according to claim 1, wherein (b) is represented by the general formula [(A)-(B1)].
n- (A), [(A)-(B2)] n- (A), or [(A)-(B3)] n- (A) (where n is an integer of 1 or more and a repeating unit of ( A), (B1), (B2) and (B3) may be the same or different).) The thermoplastic elastomer composition according to claim 1, which is a hydrogenated diene copolymer. 3. The thermoplastic elastomer composition according to claim 1, wherein in (b), the conjugated diene is butadiene and the vinyl aromatic compound is styrene. (A) per 100 parts by weight of the following (c)
The thermoplastic elastomer composition according to claim 1, which contains 250 parts by weight or less. (C): ethylene-α-olefin copolymer 5. A molded article comprising the thermoplastic elastomer composition according to any one of claims 1 to 4.