WO2000075229A1 - Thermoplastic elastomer composition and formed article thereof - Google Patents

Abstract

A thermoplastic elastomer composition which comprises 100 parts by weight of (i) a polyolefin-based resin and 10 to 1000 parts by weight of (ii) a hydrogenated diene-based copolymer, and satisfies the following requirements: (1) the copolymer (ii) contains structural units of (A) a vinyl aromatic compound polymer block and (B) a block having a structure obtained by hydrogenation of a specific copolymer containing a unit derived from a conjugated diene; (2) the copolymer (ii) has a total content (T) of units derived from vinyl aromatic compounds of 10 to 18 wt.%; (3) the copolymer (ii) has a percentage (S) of a content of the unit (A) described in (1) to the above total content of units derived from vinyl aromatic compounds of 3 % or more; (4) the copolymer (ii) has a proportion (V) of the number of hydrogenated conjugated diene units having a side chain containing two or more carbon atoms to the number of the hydrogenated conjugated diene units of 60 % or more; (5) the copolymer (ii) satisfies the formula: V ≤ 0.375 S + 1.25 T + 40; (6) 80 % or more of the units derived from a conjugated diene in the copolymer (ii) are hydrogenated; and (7) the copolymer (ii) has a number average molecular weight of 50,000 to 600,000.

Description

 Specification

 TECHNICAL FIELD The present invention relates to a thermoplastic elastomer composition and a molded article thereof.

 TECHNICAL FIELD 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 gen-based copolymer having a specific structure as essential components, has excellent flexibility, and has a melting point 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 that does not emit gloss even when heated to a temperature, and a molded article thereof. Background art

 Conventionally, vinyl chloride resin has been widely used in automotive interior and exterior parts, home appliances, stationery, office automation equipment, packaging containers, and sporting goods. However, from the viewpoint of global environmental problems, etc., replacement of vinyl chloride luster by other resins has been promoted, and as a substitute resin, thermosetting resin containing polyolefin resin and styrene-based thermoplastic elastomer has been developed. A plastic elastomer composition has been proposed (see, for example, Japanese Patent Publication No. 3-72512).

 Japanese Patent Application Laid-Open No. 3-72512 discloses a hydrogenated gen-based copolymer composition comprising a non-polar resin such as polypropylene and a hydrogenated gen-based copolymer having a specific structure. I have. A molded article made of the composition has excellent flexibility. However, a molded article made of the hydrogenated gen-based copolymer composition disclosed in the same publication emits gloss when heated at a temperature of about 80 ° C. to a temperature lower than the melting point of the polyolefin-based resin. When used, there was a problem of causing defects (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).

 Disclosure of the invention

An object of the present invention is to contain a polyolefin-based resin and a specific hydrogenated gen-based copolymer as essential components, have excellent flexibility, and furthermore, at a temperature of about 80 ° C. to less than the melting point of the polyolefin-based resin. An object of the present invention is to provide a thermoplastic elastomer composition capable of providing a molded article which does not emit gloss when heated, and a molded article thereof. That is, the first invention of the present application is:

 (i) 100 parts by weight of polyolefin resin and

 (ii) containing 10 to 1000 parts by weight of a hydrogenated gen copolymer,

 The hydrogenated gen-based copolymer (ii) relates to a thermoplastic elastomer composition which satisfies all of the following conditions (1) to (7):

 (1): The hydrogenated gen-based copolymer contains the following structural units (A) and (B)

 (A): vinyl aromatic compound polymer block

 (B): at least one block selected from the group consisting of the following (Bl), (B2) and (B3) forces

 (B 1): block obtained by hydrogenating a random copolymer block of a vinyl aromatic compound and a conjugated gen

 (B2): a block comprising a vinyl aromatic compound and a conjugated diene, and a hydrogenated tapered block in which the vinyl aromatic compound is gradually increased.

 (B3): block obtained by hydrogenating a conjugated gen polymer block

(2): Total vinyl aromatic compound unit content (T) contained in the hydrogenated gen-based copolymer is 10 to 18% by weight.

 (3): Ratio of the content of the vinyl aromatic compound unit of (A) in the above condition (1) to the total content of the vinyl aromatic compound unit in the hydrogenated gen-based copolymer (S: percentage) Is 3% or more

 (4): The ratio of the number of hydrogenated conjugated units having a side chain of 2 or more carbon atoms to the total number of hydrogenated conjugated units in the hydrogenated gen-based copolymer (V: percentage) is 60%. Exceeding

 (5): The relationship between (T) of the above condition (2), (S) of the above condition (3) and (V) of the above condition (4) in the hydrogenated gen-based copolymer is expressed by the following formula (1). )

 V≤ 0.375 X S + 1.25 XT + 40 (1)

(6): 80% or more of the double bonds of the conjugated gen unit in the hydrogenated gen-based copolymer must be hydrogenated. (7): The hydrogenated gen-based copolymer has a number average molecular weight of 50,000 to 600,000. Further, the second invention of the present application relates to a molded article comprising the thermoplastic elastomer composition of the first invention.

 Component (i) contained in the thermoplastic elastomer composition of the present invention is a polyolefin-based resin, and is at least one selected from the group consisting of homopolymers or copolymers of olefins having high crystallinity.

 Examples of such olefins include olefins having 2 to 8 carbon atoms, such as ethylene, propylene, 1-butene, 1_hexene, and 1-octene. Examples of (i) include polyethylene, polypropylene, poly (1-butene), copolymers of propylene and ethylene, and copolymers of propylene with other α-olefins (eg, 1-butene). Coalescence and the like.

 When (i) is a propylene-ethylene copolymer resin or a propylene-11-butene copolymer resin, the thermoplastic elastomer composition of the present invention provides a molded article having excellent heat resistance and flexibility. It is preferable in that it is possible.

 The crystallinity of (i) is usually at least 50%, preferably at least 60%. Here, “crystallinity” refers to only the olefin units having the highest weight content in the resin used, and manufactured using the same catalyst system and under the same conditions (temperature, pressure, amount of catalyst used, etc.). The ratio of the heat of fusion of (i) to the heat of fusion of the crystalline polyolefin homopolymer is shown. The heat of fusion is determined by the DSC method.

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

The melt flow rate (MFR) of (i) measured at 230 ° C and a load of 2.16 kgf in accordance with SK-1720 is usually 0.1 to 500 g. Minutes, preferably; 3300 g Z 10 Within the range of 0 min.

The component (ii) contained in the thermoplastic elastomer composition of the present invention includes the components (1) to (4) described above. (7) Hydrogenated copolymer which satisfies all of the above conditions.

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

 The bullet aromatic compound may have a substituent such as an alkyl group (eg, a methyl group) at the 1- or 2-position of the bullet group. Examples of the bur aromatic compound include a Bier aromatic compound having 8 to 12 carbon atoms such as styrene, p-methynolestyrene, α-methynolestyrene, t-butynolestyrene, dibutylbenzene, and butylpyridine. can give. Among them, styrene is preferably used from an industrial viewpoint.

 Condition (JJ

 (ii) is a hydrogenated diene copolymer containing the following structural units (A) and (B):

 (A): vinyl aromatic compound polymer block

 (B): at least one block selected from the group consisting of the following (Bl), (B2) and (B3) forces

 (B 1): a block obtained by hydrogenating a random copolymer block of a butyl aromatic compound and a conjugated gen

 (B2): a block comprising a vinyl aromatic compound and a conjugated diene, and a hydrogenated tapered block in which the vinyl aromatic compound is gradually increased.

 (B3): a block obtained by hydrogenating a conjugated diene polymer block.

 (ii) usually has the general formula:

 [(A) one (B)] n,

 [(A) one (B)] n— (A), or

 [(B) one (A)] n- (B)

(However, n is an integer of 1 or more, and when one or both of (A) and (B) are contained in plurals, a plurality of (A) and (B) are different even if they are the same. May be. )

For example, [(A) — (B 1)] n— (A), [(A) — (B 2)] n— (A), or [(A)-(B 3) )] n— (A) (where n is an integer of 1 or more, and the repeating units (A), (Bl), (B2), and (B3) are different even if they are the same. And hydrogenated gen-based copolymers represented by the following formula:

 Among them, hydrogenated gen-based copolymers represented by (A) — (B 1)-(A), (A)-(B 2)-(A) or (A) — (B 3)-(A) However, hydrogenated styrene-butadiene-styrene-styrene copolymer, hydrogenated styrene-butadiene-styrene copolymer, styrene-isoprene-styrene-styrene copolymer are preferable. The combined hydrogenated product and the hydrogenated product of styrene-l-f-soprene-styrene copolymer are preferred in that they can be industrially easily produced. In particular, the hydrogenated styrene-butadiene-styrene copolymer is excellent in the strength and cold shock resistance of the obtained molded article, and the strength of the obtained molded article is excellent in hydrogenation of the hydrogenated gen-based copolymer described later. The ratio of the number of hydrogenated conjugated gen units having side chains of 2 or more carbon atoms to the number of total conjugated diene units (V: percentage), even if there is a subtle manufacturing “run-out” It is also preferable because it is hardly affected. In the present specification, “1” included in the copolymer name indicates a boundary between blocks, and “” indicates that two or more compounds are used in combination in one block.

 Condition (2)

The total content of the aromatic compound unit in (ii) needs to be in the range of 10 to 18% by weight, and preferably in the range of 12 to 17% by weight. When the total content of the aromatic compound units exceeds 18% by weight, a molded article obtained by molding the thermoplastic elastomer composition tends to be hard. If the unit content of all vinyl aromatic compounds is less than 10% by weight, there is a problem that the obtained molded article has adhesiveness. The total vinyl aromatic compound unit content can be determined by ¹ H-NMR measurement using a solution of (ii) such as carbon tetrachloride at a frequency of 9 OMHz or more.

Condition (3) ― The ratio (S: percentage) of the vinyl aromatic compound unit content of the (A) vinyl aromatic compound polymer block to the total vinyl aromatic compound unit content of (ii) must be 3% or more. , Preferably 30 to 100%, more preferably 50 to 100%. If the ratio is less than 3%, there is a problem that the obtained molded article has tackiness. The ratio can be determined by ¹ H-NMR measurement at a frequency of 9 OMHz or more using a solution of carbon tetrachloride (ii).

 Condition (4)

 In (ii), the ratio (V: percentage) of the number of hydrogenated conjugated gen units having a side chain having 2 or more carbon atoms to the total number of hydrogenated conjugated gen units of the conjugated gen-based copolymer is It is necessary to be at least 60%, preferably from 60 to 85%, particularly preferably from 65 to 80%. If the force and the ratio of the stiffness are less than 60%, the obtained molded body will be hard. In addition, such a ratio can be determined by the Mole-mouth method using infrared analysis.

 Condition (5)

 In (ii), the total content of the vinyl aromatic compound unit (T) is the ratio of the content of the vinyl aromatic compound unit of the vinyl aromatic compound polymer block to the total content of the vinyl aromatic compound unit (S: percentage) ) And the ratio of the number of hydrogenated conjugated gen units having 2 or more side chains to the number of hydrogenated conjugated gen units in the hydrogenated gen-based copolymer (V: percentage) Must be represented by the following equation (1).

 V≤ 0.375 XS + 1.25 XT + 40 (1) In equation (1), if the right side (V) exceeds the value on the right side (0.375 XS + 1.25 XT + 40), When the obtained molded body is heated at a temperature of about 80 ° C. to a temperature lower than the melting point of the polyolefin-based resin, the molded body has a problem that it emits gloss.

 Condition (6)

It is necessary that at least 80% of the double bonds of the conjugated gen unit in (ii) be hydrogenated, and it is preferred that the hydrogenation is at least 90%, particularly preferably at least 96%. When the degree of hydrogenation is less than 80%, there is a problem that the light resistance of the obtained molded article is reduced.

 Condition (7)

 It is necessary that the number average molecular weight of (ii) is from 50,000 to 600,000 in order to obtain a molded article having excellent ^ M and strength, and preferably from 100,000 to 500,000. 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 the GPC method.

 The melt flow rate (MFR) of (ii) measured at 230 ° C and a load of 2.16 kgf in accordance with JISK-7210 is 0.1 to 200 g Z 10 minutes. It is preferably 1 to 100 g / 10 minutes, particularly preferably 3 to 80 g Z10 minutes, since a molded article having sufficient appearance and strength can be obtained. preferable. (Ii) used in 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 such a functional group-modified product is used, for example, when the obtained molded product is bonded to a polyurethane foam layer to produce a two-layer molded product or a multilayer molded product, the advantage that the adhesiveness is improved is obtained. It is possible. '

 Such hydrogenated gen-based copolymers are disclosed in, for example, JP-A-3-725212, JP-A-5-271325, JP-A-5-271327 It can be produced by a method described in Japanese Patent Application Laid-Open No. 6-287365.

 The thermoplastic elastomer composition of the present invention may contain, in addition to the essential components (i) and (ii), (ii i) an ethylene-α-olefin copolymer.

 When (i ii) is contained, the thermoplastic elastomer composition of the present invention is excellent in cold mold resistance without deteriorating the moldability, flexibility and non-gloss properties of the thermoplastic elastomer composition. give.

(i ii) Ethylene-α-olefin copolymer is defined as ethylene and A polymer having little crystallinity or a polymer having a crystallinity of less than 50%, such as a copolymer of yne, a copolymer of ethylene, α-olefin and a non-conjugated gen. Here, the crystallinity refers to 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. Is shown. The heat of fusion is determined by the DSC method.

 Here, α-olefins include those having 3 to 10 carbon atoms such as propylene, 1-butene, and 3-methyl-1-butene, and dicyclopentadiene and 5-2-ethylidene norbornene as non-conjugated diene. Examples thereof include non-conjugated diene having 5 to 15 carbon atoms, such as 1,4-hexadiene, 1,5-cyclooctadiene, and 5-methylene-12-norbornene. Such ethylene-α-olefin copolymers include, for example, ethylene-propylene copolymer, ethylenebutene copolymer, ethylene-11-hexene copolymer, ethylene-11-octene copolymer and ethylene-one-olefin copolymer. Propylene-5-ethylidene-2-norbornene copolymer (hereinafter referred to as “EPDM”). Such an ethylene-α-olefin copolymer may be crosslinked.

The α-olefin unit content in (iii) is preferably 5 to 40% by weight. / ₀ , more preferably in the range of 10-35% by weight, the ethylene unit content is usually 60-95% by weight, preferably 65-90% by weight. The α-olefin unit content and the ethylene unit content can be determined by ¹³ C-NMIT, infrared absorption spectroscopy, and 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, the ethylene-α-olefin copolymer is subjected to a temperature of 100 ° C according to ASTM D-927-57 °. The Mooney viscosity [ML _{1 + 4} (100 ° C.)] measured in the above is preferably in the range of 10 to 350, more preferably 15 to 300.

 When (iii) is used, the amount of (iii) is not more than 250 parts by weight, preferably 20 to 200 parts by weight, per 100 parts by weight of (i). If (iii) is excessive, the obtained molded article may have a sticky feeling.

Further, the thermoplastic elastomer composition of the present invention contains (iv) a styrene-based thermoplastic elastomer other than the above (ii) in addition to the essential components (i) and (ii). May have. As (iv), for example, the same structural unit as described in (ii) above

Hydrogenated copolymers containing (A) and (B), hydrogenated products of vinyl aromatic compound monoconjugated genomic random copolymers and the like can be mentioned. As (iv), a hydrogenated copolymer containing the same structural units (A) and (B) as described with respect to (ii), but under the conditions (2) to (4) described in (ii) above. At least one condition of (7) is a hydrogenated gen-based copolymer that is not satisfied.

 For example, when the hydrogenated copolymer which does not satisfy the condition (5) but satisfies the conditions (1) to (4) and (6) to (7) is used (V> 0.375 X S + 1. When the relational expression of 25 XT + 40 is satisfied), a thermoplastic elastomer composition having more excellent scratch resistance is provided.

 When a hydrogenated gen copolymer that does not satisfy the condition (4) is used (having a side chain having 2 or more carbon atoms with respect to the total number of hydrogenated conjugated gen units in the hydrogenated gen copolymer) When the ratio of the number of hydrogenated conjugated units (V: percentage) is 60% or less, a hydrogenated gen-based copolymer is used, and a thermoplastic elastomer composition having more excellent cold impact resistance is provided.

 When (iv) is used, the amount of (iv) is not more than 250 parts by weight, preferably 20 to 200 parts by weight, per 100 parts by weight of (i). If (iv) is excessive, for example, the obtained molded article may have a sticky feeling.

The thermoplastic elastomer composition of the present invention may contain, in addition to the essential components (i) and (ii), a (V) hydrogenated conjugated polymer. Examples of (V) include hydrogenated products of polybutadiene and hydrogenated products of polyisoprene. In (V), the ratio (V: percentage) of the number of hydrogenated conjugated units having a side chain having 2 or more carbon atoms to the total number of hydrogenated conjugated units is more than 60%. Although it is preferable from the viewpoint of the flexibility of the resulting molded article, the hydrogenated gen polymer may be composed of two or more blocks having different ratios. Examples of such a hydrogenated gen polymer include a polymer described in JP-A-3-74409 and CEBC 6200 manufactured by JSR Corporation. When the thermoplastic elastomer composition of the present invention contains (V), the strength of the obtained molded article is improved (particularly when the thermoplastic elastomer composition contains (iii)). . When (v) is used, the amount of (v) is not more than 250 parts by weight, preferably 2 to 200 parts by weight, per 100 parts by weight of (i). If (V) is too large, the obtained 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, and acrylic rubber, ethylene-acrylic acid copolymer, ethylene-monoacetic acid copolymer and saponified product thereof. It may contain other polymer components such as ethylene-methyl methacrylate copolymer, ethylene-acrylic acid daricidyl acetate vinyl acetate copolymer, ethylene-methacrylic acid glycidyl acetate vinyl acetate copolymer.

 The thermoplastic elastomer composition of the present invention may be, for example, a mineral oil-based softening agent, a heat stabilizer such as a phenol-based, sulfite-based, phenylalkane-based, phosphite-based, amine-based, or amide-based heat-resistant agent, or weather-resistant. It may contain various additives such as stabilizers, antistatic agents, pigments, metallic soaps, waxes, fungicides, antibacterial agents, and fillers. 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 that is hardly discolored even when wiped with an organic solvent such as hexane, benzene, and toluene. Examples of pigments include organic pigments such as azo, phthalocyanine, sullen, and dye lakes, oxides such as titanium oxide, molybdate cromoate, selenium sulfide compounds, inorganic compounds such as cyanide cyanide, and carbon black. Pigments are 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 stone, or magnesium oxide can also be used. In this case, the primary particle size of the carrier is usually 10 m or less, preferably 1 to 5 / m. In this case, the weight ratio of the powdered pigment to the carrier is usually 20:80 to 80:20, preferably 25:75 to 75:25. The thermoplastic elastomer composition for powder molding of the present invention contains the above U) and (ii) as essential components, and if necessary, at least one of (iii), (iv) and (v) It contains. The content of (ii) is: (i) 100 parts by weight of (ii) Must be contained in an amount of 10 to 1000 parts by weight, preferably 40 to 200 parts by weight. (I) If the content of (ii) is less than 10 parts by weight relative to 100 parts by weight, the obtained molded article has poor flexibility. The heat resistance and light resistance are insufficient. The MFR of the thermoplastic elastomer composition of the present invention is preferably from 0.1 to 200 gZl O from the viewpoint of moldability of the thermoplastic elastomer composition and appearance of the obtained molded article. Is preferably 0.5 to 100 g / 10 minutes. Examples of the method for preparing the thermoplastic elastomer composition of the present invention include the following methods.

 That is, at least one of (i) and (ii) and (iii), (iv) and (V) blended as required may be melt-kneaded. Alternatively, it can also 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, the present invention contains (i), (ii), (iii), (iv) and (v), and (i) and Z or (iii) are intramolecular and Z or intermolecularly crosslinked. The thermoplastic elastomer composition is usually produced by dynamically cross-linking (i) and (iii) and then kneading (ii), (iv) and (v) with added calo. Can be. Here, for kneading, a single-screw extruder, a twin-screw extruder, an ader, a roll, or the like can be used. The above-mentioned various additives and various polymers are compounded, for example, by using (i), (ii), (iii), (iv) or (v) in which these additives are previously compounded, It can be carried out 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 a crosslinking agent, an organic peroxide such as 2,5-dimethyl-2,5-di (tert-butylperoxyno) hexane, dicumyl peroxide is usually used. The crosslinking agent is usually not more than 1 part by weight per 100 parts by weight of the total of at least one of (i) and (ii) to be crosslinked and (iii) and (iv) optionally added. It is preferably used in the range of 1 to 0.8 part by weight, more preferably 0.2 to 0.6 part by weight. When an organic peroxide is used as a cross-linking agent, the presence of a cross-linking aid such as a bismaleimide compound When dynamic crosslinking is performed in the presence, a thermoplastic elastomer composition that gives a molded article having excellent heat resistance can be obtained. In this case, the amount of the organic peroxide used depends on (i), (ii), and if necessary, (iii), (iv),

 Usually, 0.8 parts by weight or less, preferably 0.2 to 0.8 parts by weight, more preferably 0.2 to 0.8 parts by weight, per 100 parts by weight of the components to be crosslinked among at least one of (v) It is in the range of 0.4 to 0.6 parts by weight.

 The amount of the crosslinking assistant used is a total of 100 parts by weight of at least one of (i) and (ii) to be crosslinked and (iii) and (iv) optionally combined. The amount is usually 1.5 parts by weight or less, preferably 0.2 to 1 part by weight, more preferably 0.4 to 0.8 part by weight. The crosslinking aid is preferably blended before the addition of the crosslinking agent, and is usually added when the components to be crosslinked are preliminarily kneaded. The bridge can be formed by kneading under heating, for example, in a temperature range of 150 to 250 ° C using a single-screw extruder or a twin-screw extruder. Crosslinking can also be performed by a method such as sulfur crosslinking.

 These additives and other polymer components are used by being contained in advance in at least one of (i) and (ii) and (iii), (iv) and (V) used as needed. It may be blended at the time of the above-mentioned kneading or dynamic cross-linking or afterwards by kneading.

 When a mineral oil-based softening agent is used, if the oil-extended ethylene-monoolefin copolymer containing the mineral oil-based softening agent previously contained in (iii) is used, the above-described kneading and dynamic bridging are facilitated. Can be done.

In order to produce the thermoplastic elastomer composition of the present invention, the degree of the above-mentioned kneading and dynamic cross-linking, the types and amounts of each component constituting the thermoplastic elastomer composition, the amount thereof used, The type and amount of the cross-linking agent and the cross-linking auxiliary, the type of the additive and the amount thereof are appropriately selected. Above all, the shear rate in kneading and dynamic crosslinking greatly affects the above physical properties, and it is preferable to perform kneading and dynamic crosslinking at a shear rate of 1 × 10 ³ sec− ¹ or more.

The thermoplastic elastomer composition of the present invention is molded by a method such as an injection molding method, an extrusion molding method, a vacuum molding method, or a compression molding method to produce a molded article having a desired shape. Can be. 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 in the range of 180 to 300 ° C. is there.

 It is to be noted that a foamed molded article can be manufactured by molding the thermoplastic elastomer composition of the present invention containing a foaming agent, and further foaming the molded article. 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 azodicarbonamide, azo compounds such as 2,2′-azobisbisbutyronitrile, diazodiaminobenzene, benzenesulfonylhydrazide, benzene-1,3 —Sulfonyl hydrazide compounds such as sulfonyl hydrazide and p-toluenesulfonyl hydrazide; N, N ′ —dinitroso pentamethylenetetramine; Includes carbonates such as azide compounds, sodium bicarbonate, ammonium bicarbonate, and ammonium carbonate. Among them, azodicarbonamide is preferably used. The compounding of the blowing agent is usually carried out at a temperature not higher than the arcing temperature of the blowing agent. In addition, a foaming aid and a cell conditioner may be contained together with the foaming agent.

 Although the molded article made of the thermoplastic elastomer composition of the present invention is useful as a non-foamed material, it can be used as a two-layer molded article in which a foamed layer is laminated on one surface side, or it can be used as a molded article. Alternatively, the two-layer molded body is a multi-layer molded body in which a thermoplastic resin core material is laminated on one side (in the case of a two-layer molded body composed of a non-foamed layer and a foamed layer, the foamed layer side). It can also be used.

 Example

 Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

 The methods for measuring various characteristics in the examples are as follows.

 [1] Total vinyl aromatic compound unit content in (ii)

Using the carbon tetrachloride solution of (ii), it was determined by ¹ H_NMR measurement method (frequency: 90 MHz). [2] (A) Ratio of vinyl aromatic compound content in vinyl aromatic compound polymer block to total vinyl aromatic compound content in hydrogenated gen-based copolymer in (ii) (S)

 Using the carbon tetrachloride solution of (ii), — determined by NMR measurement (frequency 90 MHz).

 [3] The ratio of the number of hydrogenated conjugated gen units having a side chain having 2 or more carbon atoms to the number of hydrogenated conjugated gen units in (ii) (V)

 It was determined by the Morero method using infrared analysis.

 [4] Hydrogenation rate of double bond of conjugated gen unit in hydrogenated gen-based copolymer

 Using the carbon tetrachloride solution of (ii), it was determined by NMR method (frequency 90MHz).

 (5) Number average molecular weight of (ii)

 It was determined by gel permeation chromatography (GPC) at 38 ° C using the tetrahydrofuran solution of (ii) in terms of polystyrene.

 [6] Flexibility of molded body 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 1 mm thick molded sheet obtained by the compression molding method described below was used to control the gear inside the tank to 110 ° C. The sample was placed in an oven (semi-explosion-proof dryer manufactured by Yamato Scientific Co., Ltd.) for 24 hours, and the change in gloss value (gloss) before and after heating was determined based on the following criteria. The Darros value was measured by a digital gloss meter (Murakami Color Research Laboratory, GM-26D, reflection angle 60 °).

 〇: Difference of Daros value is less than 1.0

 Δ: Difference in gross value is 1.0 or more and less than 2.5

 X: Difference of Darros value is 2.5 or more

 Example 1

O分〕 100重量部、 スチレンーブタジェ ン - スチレン一スチレン共重合体の水添物 〔 (A) 一 （B 1) — (A) 構造に該 当、 全スチレン単位含有量 16重量％、 全スチレン単位含有量に対する （A) 部 のビュル芳香族化合物単位含有量 85%、 M F R = 10 g Z 10分、 水添された 全共役ジェン単位に対する炭素数 2以上の側鎖を有する水添された共役ジェン単 位の割合は 75 %、 水添率 98%、 数平均分子量 1 3万〕 100重量部、 及び黒 色顔料カーボンブラック 1重量部 （プロピレン一エチレン共重合体樹脂 100重 量部当たり） を単軸混練機 〔田辺プラスチック機械株式会社製、 VS40mm エキストルーダー〕 を用いて、 温度 1 70°Cで混練して組成物を得、 これを切断 機を用いて切断してペレットを得た。 このペレットを、 プレス成形機 〔関西ロー ノレ株式会社製、 P E SW- 5040〕 を用いて、 しぼ模様金型で 1 70°C、 30 kg fZcm²で余熱後、 1 50 k g f Zcm²で加圧冷却することにより、 し ぼ模様付き （厚み lmm) 熱可塑性エラストマ一組成物の成形体を得た。 この成 形体の評価結果を表 1及び表 2に示す。 Propylene one ethylene copolymer resin [manufactured by Sumitomo Chemical Co., Ltd., ethylene unit content of 5 wt _^0/0,

O content) 100 parts by weight, styrene butage Hydrogenated product of styrene-styrene-styrene copolymer [Applicable to (A)-(B1)-(A) structure, total styrene unit content of 16% by weight, (A) part based on total styrene unit content 85% of BU aromatic units, MFR = 10 g Z 10 min, 75% of hydrogenated conjugated units having side chains with 2 or more carbon atoms to all hydrogenated conjugated units. 100% by weight of hydrogenation rate 98%, number average molecular weight 130000] and 1 part by weight of black pigment carbon black (per 100 parts by weight of propylene-ethylene copolymer resin) in a single-axis kneader [Tanabe Plastic Machinery Co., Ltd.] Using a VS40mm extruder (manufactured by a company) at a temperature of 170 ° C. to obtain a composition, which was cut using a cutter to obtain pellets. The pellets are preheated at 170 ° C, 30 kg fZcm ² in a grain pattern mold using a press molding machine [Kansai Lonore Co., Ltd., PE SW-5040], and then pressurized at 150 kgf Zcm ^2. By cooling, a molded article of a thermoplastic elastomer composition having a grain pattern (thickness: lmm) was obtained. Tables 1 and 2 show the evaluation results of this compact.

 Example 2

 10% by weight of total styrene units, 80% of the content of the BU aromatic unit in part (A) based on the total content of styrene units, MFR = 15 gZl 0 min, carbon number based on all hydrogenated conjugated gen units Hydrogenated styrene butene / styrene-styrene copolymer having 70% hydrogenated conjugated unit having 2 or more side chains, 98% hydrogenation ratio, and a number average molecular weight of 160,000 A molded product was obtained in the same manner as in Example 1 except that ((A) — (B1) — (A) corresponding to the structure) was used. Table 1 shows the evaluation results.

 Example 3

Total styrene unit content 15 wt%, part (A) part of butyl aromatic compound unit content 80% based on total styrene unit content, MFR = 34 gZl 0 min, carbon number 2 based on total hydrogenated conjugated gen units 2 The proportion of hydrogenated conjugated gen units having the above side chains is 75%, the hydrogenation rate is 98%, and the number average molecular weight is 120,000. A molded product was obtained in the same manner as in Example 1, except that (A) — (B 1) — (A) corresponding to the structure) was used. The evaluation results are shown in Tables 1 and 2. Example 4

 15% by weight of total styrene unit content, 100% of the content of the BU aromatic unit in part (A) based on the total content of styrene unit, MF R = 3 1 g / min, 10 minutes, based on all hydrogenated conjugated gen units Hydrogenated styrene-butadiene-styrene copolymer having 79% hydrogenated conjugated unit having a side chain of 2 or more carbon atoms, 98% hydrogenation ratio and 120,000 number average molecular weight A molded body was obtained in the same manner as in Example 1 except that ((A) — (B 3) — (corresponding to the (A) structure)). Table 1 shows the evaluation results. Comparative Example 1

 Total styrene unit content 10% by weight, part (A) part of the aromatic compound unit content of the styrene unit content 40%, MFR = 10 g Z 10 minutes, number of carbon atoms relative to the total hydrogenated conjugated unit 2 The ratio of the hydrogenated conjugated gen units having the above side chains is 80%, the hydrogenation ratio is 98%, and the number average molecular weight is 200,000. A) — (B1) — (A) The molded body was obtained in the same manner as in Example 1 except that (A) was used. The evaluation results are shown in Tables 1 and 2.

 Comparative Example 2

All styrene unit content of 1 9 wt _^0/0, the total styrene units with respect to the content (A) unit Bulle aromatic compound unit content of 100%, MF R = 30 gZ 10 minutes, for hydrogenated been total conjugated diene units The ratio of hydrogenated conjugated units having a side chain of 2 or more carbon atoms is 42%, the hydrogenation rate is 98%, and the number average molecular weight is 120,000.Styrene-butadiene 'water of styrene-styrene copolymer A molded product was obtained in the same manner as in Example 1 except that the additive ((A) — (B 3) — corresponding to the (A) structure) was used. The evaluation results are shown in Tables 1 and 2.

 Comparative Example 3

Total styrene unit content: 14% by weight, part (A) part of the aromatic aromatic compound unit content: 45% based on the total styrene unit content, MFR = 11 gZl 0 minutes, number of carbon atoms per hydrogenated total conjugated gen unit: 2 The ratio of hydrogenated conjugated gen units having the above side chains is 78%, the hydrogenation ratio is 98%, and the number average molecular weight is 200,000. Styrene butagen ■ Hydrogenated styrene-styrene copolymer (( A) — (B 1) — (A) A molded article was obtained in the same manner as in Example 1 except that the above was used. Tables and Table 2 show the evaluation results.

 table 1

 (ii) Hydrogenated copolymer

表 2

Table 2

 Evaluation results of thermoplastic elastomer monofilament molded products

実施例 5

Example 5

In Example 1, 100 parts by weight of a propylene-ethylene copolymer resin [manufactured by Sumitomo Chemical Co., Ltd., ethylene unit content 5% by weight, MFR = 20 gZlO content] Hydrogenate of styrene-butadiene-styrene copolymer [(A)-(B3)-(A) Structure, total styrene unit content 15% by weight, based on total styrene unit content

(A) Part of the aromatic compound unit content of 100%, MFR = 30 g Z for 10 minutes, hydrogenated co-gen units having a side chain of 2 or more carbon atoms with respect to all hydrogenated conjugated units. the proportion of 80%, hydrogenation ratio of 98%, a number average molecular weight 130,000] 100 parts by weight of ethylene one propylene copolymer rubber [manufactured by Sumitomo Chemical Co., Ltd., Esprene V 0141, a propylene unit content 27 wt _^0/0 , MFR = 0.7 g Z 10 minutes] A molded article was obtained in the same manner as in Example 1 except that 50 parts by weight and 2.5 parts by weight of the black pigment carbon black were used. Tables 3 and 4 show the evaluation results of this molded body.

 Table 3 (ii) Hydrogenated copolymer

表 3熱可塑性ェラストマー組成物成形体の評価結果

Table 3 Evaluation results of the molded thermoplastic elastomer composition

発明の効果

The invention's effect

As described above, according to the present invention, a polio-based resin and a specific structure A molded article that contains a hydrogenated gen-based copolymer as an essential component, has excellent flexibility, and does not emit gloss when heated to a temperature of about 80 ° C to less than the melting point of the polyolefin resin, and its molding Provide a thermoplastic elastomer composition that can provide body

Claims

The scope of the claims  1. (i) 100 parts by weight of polyolefin resin and  (ii) containing 10 to 1000 parts by weight of a hydrogenated gen copolymer,  The hydrogenated gen-based copolymer (ii) is a thermoplastic elastomer composition that satisfies all of the following conditions (1) to (7):  (1): The hydrogenated gen-based copolymer contains the following structural units (A) and (B)  (A): vinyl aromatic compound polymer block  (B): at least one block selected from the group consisting of (Bl), (B2) and (B3) below  (B 1): block obtained by hydrogenating a random copolymer block of a vinyl aromatic compound and a conjugated gen  (B2): a block comprising a hydrogenated aromatic compound and a conjugated diene, and a hydrogenated tapered block in which the volume of the hydrogenated aromatic compound is gradually increased  (B3): block obtained by hydrogenating a conjugated gen polymer block  (2): Total vinyl aromatic compound unit content (T) contained in the hydrogenated gen-based copolymer is 10 to 18% by weight.  (3): Ratio of the content of the vinyl aromatic compound unit of (A) in the above condition (1) to the total content of the vinyl aromatic compound unit in the hydrogenated gen-based copolymer (S: percentage) Is 3% or more  (4): The ratio of the number of hydrogenated conjugated units having a side chain of 2 or more carbon atoms to the total number of hydrogenated conjugated units in the hydrogenated gen-based copolymer (V: percentage) is 60%. Exceeding  (5): The relationship between (T) of the above condition (2), (S) of the above condition (3) and (V) of the above condition (4) in the hydrogenated gen-based copolymer is expressed by the following formula (1). )  V≤ 0.375 X S + 1.25 XT + 40 (1) (6): 80% or more of the double bonds of the conjugated gen units in the hydrogenated gen-based copolymer must be hydrogenated. (7): The hydrogenated gen copolymer has a number average molecular weight of 50,000 to 600,000.  2. Hydrogenated copolymer (ii) Power General formula:  [(A) — (B 1)] n— (A),  [(A)-(B 2)] n- (A), or  [(A)-(B 3)] n- (A)  (However, n is an integer of 1 or more, and the repeating units (A), (Bl), (B2) and (B3) may be the same or different.) 2. The thermoplastic elastomer composition according to claim 1, which is a hydrogenated gen-based copolymer represented by the following formula:  3. The thermoplastic elastomer composition according to claim 1, wherein in the hydrogenated gen-based copolymer (ii), the conjugated gen is butadiene, and the vinyl aromatic compound is styrene.  4. The thermoplastic elastomer composition according to claim 1, which contains (iii) 250 parts by weight or less of an ethylene / one-year-old olefin-based copolymer per 100 parts by weight of the polyolefin-based resin (i).  5. A molded article comprising the thermoplastic elastomer composition according to any one of claims 1 to 4.