JP2007169444A - Thermoplastic elastomer composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer composition which gives injection molded articles having excellent dimensions, rich flexibility, excellent oil resistance and excellent abrasion resistance, heat resistance and low temperature flexibility. <P>SOLUTION: This thermoplastic elastomer composition comprises: (A) an acrylic block copolymer comprising an acrylic polymer block (a) and a methacrylic polymer block (b), (B) an olefinic thermoplastic elastomer, (C) a compatibilizer, and (D) a lubricant. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermoplastic elastomer composition that is excellent in injection molding processability and rich in flexibility, and gives a molded article excellent in wear resistance, heat resistance and low temperature flexibility in addition to tensile properties and oil resistance.

  Thermoplastic elastomers are characterized by the fact that they do not require a vulcanization process and can be processed with ordinary thermoplastic resin molding machines. In recent years, automotive parts and machines that previously used vulcanized rubber have been used. Applications have been developed in a wide range of fields including parts. Among these, olefin-based thermoplastic elastomers are excellent in terms of light weight, environmental pollution resistance, and economy, and the amount of use is increasing year by year (Non-patent Document 1).

Plastics, 2004, Vol. 55, No. 3, P.17-25,

  Olefin-based thermoplastic elastomers have the problem of poor oil resistance. On the other hand, the present inventors have already found that oil resistance can be improved by blending an acrylic block copolymer having good oil resistance (PCT / JP2005 / 013239).

  However, the acrylic block copolymer has a high friction coefficient. For this reason, when an olefinic thermoplastic elastomer and an acrylic block copolymer are mixed, the friction coefficient of the mixture becomes high, and it cannot be said that sufficient wear resistance is obtained.

  The present invention provides a thermoplastic elastomer composition excellent in injection molding processability, capable of providing a molded article excellent in tensile properties, oil resistance, abrasion resistance, heat resistance and low temperature flexibility, which is rich in flexibility. The purpose is to do.

  As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that the above-mentioned problems can be solved by combining a compatibilizer and a lubricant with the composition of an olefin-based thermoplastic elastomer and an acrylic block copolymer. I found it.

  That is, the present invention provides (A) an acrylic block copolymer comprising an acrylic polymer block (a) and a methacrylic polymer block (b), (B) an olefin thermoplastic elastomer, and (C) a compatibilizing agent. And (D) a thermoplastic elastomer composition comprising a lubricant.

  The composition according to the present invention is excellent in injection molding processability, and a molded article produced using the composition is rich in flexibility and excellent in tensile properties, oil resistance, wear resistance, heat resistance and low temperature flexibility. Therefore, the thermoplastic elastomer composition according to the present invention can be suitably used for molded products for automobiles, household electrical appliances or office electrical appliances, and automotive seals.

<(A) Acrylic block copolymer>
In the present application, the acrylic block copolymer (A) means a polymer composed of an acrylic polymer block (a) and a methacrylic polymer block (b). The acrylic block copolymer (A) may be a linear block copolymer, a branched (star) block copolymer, or a mixture thereof. The structure may be appropriately selected according to processing characteristics, mechanical characteristics, and the like, but is preferably a linear block copolymer from the viewpoint of cost and ease of polymerization.

The linear block copolymer may have any linear block structure (arrangement). From the viewpoint of the physical properties or physical properties of the composition, the acrylic block copolymer (A) is used. Constituting acrylic polymer block (a) (hereinafter also referred to as polymer block (a) or block (a)) and methacrylic polymer block (b) (hereinafter referred to as polymer block (b) or block ( b))) is a general formula: (ab) _n , general formula: b- (ab) _n , general formula: (ab) _n -a (n is an integer of 1 to 3) It is preferable that it is at least 1 type of block copolymer chosen from the group which consists of block copolymer represented by these. Among these, an ab type diblock copolymer, a bab type triblock copolymer, or a mixture thereof from the viewpoint of easy handling during processing and physical properties in the case of a composition. Is preferred.

The acrylic block copolymer (A) preferably has a reactive functional group (c ₀ ) in order to have reactivity with a nonpolar material having a functional group. The reactive functional group (c) may be present in the block (a) or the block (b) or both polymer blocks.

Examples of the reactive functional group (c ₀ ) include an epoxy group, a hydroxyl group, an amino group, a carboxyl group, an acid anhydride group, and an isocyanate group.

Among these, as the reactive functional group (c ₀ ), a unit (c1) containing an acid anhydride group

および／またはカルボキシル基を含有する単位（ｃ２）

And / or a unit containing a carboxyl group (c2)

（単位（ｃ１）および（ｃ２）の式中、Ｒ^１は水素原子またはメチル基で、互いに同一でも異なっていてもよい。ｐは０または１の整数、ｑは０〜３の整数である。）（以下、単位（ｃ１）および（ｃ２）を総称して、「単位（ｃ）」とする）が、反応性や、導入の容易性の点から好ましい。

(In the formulas of units (c1) and (c2), R ¹ is a hydrogen atom or a methyl group, and may be the same or different from each other. P is an integer of 0 or 1, and q is an integer of 0 to 3. (Hereinafter, the units (c1) and (c2) are collectively referred to as “unit (c)”) are preferable from the viewpoint of reactivity and ease of introduction.

  It is preferable that at least one unit (c) is contained per molecule in the acrylic polymer block (a), the methacrylic polymer block (b), or both of these blocks. When the number is 2 or more, the mode in which the unit (c) is polymerized may be random copolymerization or block copolymerization.

  When the way of containing the unit (c) in the block copolymer is expressed by taking a b-a-b type triblock copolymer as an example, (b / c) -ab type, (b / c) -a -(B / c) type, cb-a-b type, c-b-a-b-c type, b- (a / c) -b-type, b-a-c-b type, b- It is represented by the c-a-b type, and any of these may be used. Here, (a / c) means that the unit (c) is contained in the block (a), and (b / c) means that the unit (c) is contained in the block (b). C−a− and a−c− represent that the unit (c) is bonded to the end of the block (a). Expressions are (a / c), (b / c), c-a-, a-c-, etc., all of which belong to block (a) or block (b).

  The number average molecular weight of the acrylic block copolymer (A) is preferably 30000 to 500000, more preferably 40000 to 400000, and further preferably 50000 to 300000. If the molecular weight is less than 30,000, sufficient mechanical properties as an elastomer may not be exhibited, and if it exceeds 500,000, processing properties may be deteriorated.

  The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the acrylic block copolymer (A) is preferably 1 to 2, and preferably 1 to 1.8. Is more preferable. If Mw / Mn exceeds 2, the compression set of the acrylic block copolymer (A) may deteriorate. In addition, the number average molecular weight (Mn) and the weight average molecular weight (Mw) in the present invention are obtained by obtaining molecular weight in terms of polystyrene using gel permeation chromatography with chloroform as a mobile phase.

  The composition ratio between the acrylic polymer block (a) and the methacrylic polymer block (b) constituting the acrylic block copolymer (A) is the required physical properties and molding required during processing of the composition. And the molecular weight required for each of the acrylic polymer block (a) and the methacrylic polymer block (b). If the range of the composition ratio of a preferable acrylic polymer block (a) and a methacrylic polymer block (b) is illustrated, acrylic polymer block (a) will be 50 to 90 weight% (methacrylic polymer block ( b) is preferably 50 to 10% by weight), more preferably 50 to 80% by weight (methacrylic polymer block (b) is 50 to 20% by weight), and 50 to 70% by weight ( The methacrylic polymer block (b) is more preferably 50 to 30% by weight. When the proportion of the acrylic polymer block (a) is less than 50% by weight, the mechanical properties as an elastomer, particularly the elongation at break may be lowered, or the flexibility may be lowered. In some cases, rubber elasticity at high temperatures may be reduced.

The relationship between the glass transition temperatures of the acrylic polymer block (a) and the methacrylic polymer block (b) constituting the acrylic block copolymer (A) is the glass transition of the acrylic polymer block (a). When the temperature is Tg _a and that of the methacrylic polymer block (b) is Tg _b , it is preferable to satisfy the relationship of the following formula.
Tg _a <Tg _b

  Here, the glass transition temperature (Tg) of the acrylic polymer block (a) or the methacrylic polymer block (b) is based on the following Fox formula, and the weight ratio of the monomer in each polymer block is used. Approximate value can be obtained.

_{1 / Tg = (W 1 /} Tg 1) + (W 2 / Tg 2) + ... + (W m / Tg m)
W ₁ + W ₂ + ... + W _m = 1
(In the formula, Tg represents the glass transition temperature of the polymer block, and Tg ₁ , Tg ₂ ,..., Tg _m represent the glass transition temperature of the polymerized monomer (homopolymer). W ₁ , W ₂ ,..., W _m represent the weight ratio of polymerized monomers.
The glass transition temperature of the homopolymer of each monomer in the Fox equation is described, for example, in Polymer Handbook Third Edition (Wiley-Interscience, 1989), This value is used in this specification.

  Specific examples of the acrylic block copolymer (A) include the acrylic block copolymers produced in Production Examples 1-2 and 2-2, which will be described later. Hereinafter, such an acrylic block copolymer will be described in more detail.

<Acrylic polymer block (a)>
The acrylic polymer block (a) in the acrylic block copolymer (A) has a Tg _a <Tg in relation to the glass transition temperature with the methacrylic polymer block (b) in order to develop rubber properties. _It is preferable to satisfy _b . Further, the acrylic polymer block (a) preferably contains 50 to 100% by weight of the unit containing an acrylic ester in the whole block, and more preferably contains 60 to 100% by weight. preferable. Moreover, it is preferable to contain 0-50weight% of the monomer which has a functional group used as the precursor of a unit (c), and it is more preferable to contain 0-40weight%. Furthermore, it is preferable to contain 0-50 weight% of other vinyl monomers copolymerizable with these, and it is more preferable to contain 0-25 weight%. When the proportion of the unit containing the acrylic ester is less than 50% by weight, the physical properties, particularly the elongation of the tensile properties, which are characteristic when the acrylic ester is used, may be small.

The molecular weight of the acrylic polymer block (a) may be determined from the elastic modulus and rubber elasticity required for the acrylic polymer block (a). When the number average molecular weight required for the acrylic polymer block (a) is M _A and the range is exemplified, preferably M _A > 3000, more preferably M _A > 5000, still more preferably M _A > 10000, Particularly preferably, M _A > 20000, and most preferably M _A > 40000. When the number-average molecular weight M _A of the acrylic polymer block (a) is less than the range of the tensile elongation is lowered. Moreover, the upper limit of molecular weight becomes like this. Preferably it is 500000 or less, More preferably, it is 300000 or less.

  Examples of the acrylic acid ester constituting the acrylic polymer block (a) include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, and acrylic acid. Acrylic aliphatic hydrocarbons such as n-hexyl, n-heptyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, dodecyl acrylate, stearyl acrylate, etc. 1 to 18 alkyl) ester; acrylic acid cycloaliphatic hydrocarbon ester such as cyclohexyl acrylate and isobornyl acrylate; aromatic aromatic hydrocarbon ester such as phenyl acrylate and toluyl acrylate; acrylic such as benzyl acrylate acid Esters of acrylic acid and functional group-containing alcohols having etheric oxygen such as ralalkyl ester, 2-methoxyethyl acrylate, 3-methoxybutyl acrylate; trifluoromethylmethyl acrylate, 2-trifluoromethylethyl acrylate 2-perfluoroethylethyl acrylate, 2-perfluoroethyl-2-perfluorobutylethyl acrylate, 2-perfluoroethyl acrylate, perfluoromethyl acrylate, diperfluoromethylmethyl acrylate, acrylic acid 2 -Fluoroalkyl acrylates such as perfluoromethyl-2-perfluoroethylmethyl, 2-perfluorohexylethyl acrylate, 2-perfluorodecylethyl acrylate, 2-perfluorohexadecylethyl acrylate And the like. These may be used alone or in combination of two or more. Among these acrylate esters, n-butyl acrylate is preferable from the viewpoint of low-temperature characteristics, compression set, cost, and availability. If oil resistance and mechanical properties are required, ethyl acrylate is preferred. When low temperature characteristics, mechanical characteristics, and compression set are required, 2-ethylhexyl acrylate is preferred. From the viewpoint of mechanical properties, oil resistance, and low temperature properties, in the acrylic polymer block (a) (in all acrylic polymer blocks (a)), 2-methoxyethyl acrylate is 10 to 90% by weight, acrylic acid n A mixture of 10 to 90% by weight of butyl and 0 to 80% by weight of ethyl acrylate is preferred, and further 15 to 85% by weight of 2-methoxyethyl acrylate, 15 to 85% by weight of n-butyl acrylate and 0% of ethyl acrylate A mixture of ˜70% by weight is preferred.

  Examples of the functional group serving as a precursor of the unit (c) include t-butyl acrylate, isopropyl acrylate, α, α-dimethylbenzyl acrylate, α-methylbenzyl acrylate, and t-butyl methacrylate. , Isopropyl methacrylate, α, α-dimethylbenzyl methacrylate, α-methylbenzyl methacrylate, and the like, but are not limited thereto. A method for introducing the unit (c) into the acrylic block copolymer (A) will be described later.

  Examples of the vinyl monomer copolymerizable with the acrylic ester constituting the acrylic polymer block (a) include, for example, a methacrylic ester, an aromatic alkenyl compound, a vinyl cyanide compound, a conjugated diene compound, and a halongen-containing compound. Examples thereof include unsaturated compounds, unsaturated dicarboxylic acid compounds, vinyl ester compounds, and maleimide compounds.

  Examples of the methacrylate ester include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-pentyl methacrylate, and n-hexyl methacrylate. , Aliphatic methacrylates such as n-heptyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, decyl methacrylate, dodecyl methacrylate, stearyl methacrylate (For example, alkyl having 1 to 18 carbon atoms) ester; methacrylic acid alicyclic hydrocarbon ester such as cyclohexyl methacrylate, isobornyl methacrylate; methacrylic acid aralkyl ester such as benzyl methacrylate; phenyl methacrylate Methacrylic acid aromatic hydrocarbon esters such as toluyl methacrylate; Esters of methacrylic acid such as 2-methoxyethyl methacrylate and 3-methoxybutyl methacrylate and functional group-containing alcohols having etheric oxygen; Trifluoromethyl methyl acrylate, 2-trifluoromethyl ethyl methacrylate, 2-perfluoroethyl ethyl methacrylate, 2-perfluoroethyl-2-perfluorobutyl ethyl methacrylate, 2-perfluoro methacrylate Ethyl, perfluoromethyl methacrylate, diperfluoromethyl methyl methacrylate, 2-perfluoromethyl-2-perfluoroethyl methyl methacrylate, 2-perfluorohexyl methacrylate, 2-par methacrylate Fluoro Shiruechiru, such as methacrylic acid fluorinated alkyl esters such as meta 2-perfluoro-hexadecyl acrylate and the like.

  Examples of the aromatic alkenyl compound include styrene, α-methylstyrene, p-methylstyrene, and p-methoxystyrene.

  Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile.

  Examples of the conjugated diene compound include butadiene and isoprene.

  Examples of the halogen-containing unsaturated compound include vinyl chloride, vinylidene chloride, perfluoroethylene, perfluoropropylene, and vinylidene fluoride.

  Examples of the unsaturated dicarboxylic acid compound include maleic anhydride, maleic acid, monoalkyl esters and dialkyl esters of maleic acid, fumaric acid, monoalkyl esters and dialkyl esters of fumaric acid, and the like.

  Examples of the vinyl ester compound include vinyl acetate, vinyl propionate, vinyl pivalate, vinyl benzoate, and vinyl cinnamate.

  Examples of the maleimide compound include maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide, cyclohexylmaleimide and the like.

  The vinyl monomers copolymerizable with the acrylate ester may be used alone or in combination of two or more. The vinyl monomer is required when the acrylic polymer block (a) is used as a composition, and the glass transition temperature, elastic modulus and polarity required for the acrylic polymer block (a). Depending on the physical properties and compatibility with the olefinic thermoplastic elastomer (B), preferred ones can be appropriately selected. For example, acrylonitrile can be copolymerized for the purpose of improving oil resistance.

  The glass transition temperature of the acrylic polymer block (a) is preferably 50 ° C. or lower, more preferably 0 ° C. or lower. When the glass transition temperature is higher than 50 ° C., the rubber elasticity of the acrylic block copolymer (A) may be lowered.

Setting the glass transition temperature of the acrylic polymer block _(a) (Tg a) obtains a glass transition temperature of the homopolymer of each monomer constituting the polymer block from Polymer Handbook Third Edition of the foregoing, each of the single From the polymerization ratio of the monomer, the weight ratio of the monomer constituting the polymer block can be changed according to the Fox formula.

  Specific examples of the acrylic polymer block (a) include, for example, acrylic polymer blocks contained in the acrylic block copolymer produced in Production Example 1-2 and Production Example 2-2 described later.

<Methacrylic polymer block (b)>
Acrylic block copolymer (A) in the methacrylic polymer block (b) shows the relationship between the glass transition temperature of the acrylic polymer block (a), that to meet the Tg _a <Tg _b preferable. Moreover, the unit which contains a methacrylic acid ester in a methacrylic polymer block (b) from the point of the point which is easy to obtain the acrylic block copolymer (A) of the desired physical property, cost, and availability. 10 to 99.5% by weight, preferably 20 to 99.5% by weight of a monomer having a functional group which is a precursor of the unit (c). It is preferable to contain 0.1 to 50% by weight, preferably 0.1 to 25% by weight, of other vinyl monomers that are contained in weight percent and copolymerizable therewith.

  The molecular weight of the methacrylic polymer block (b) may be determined from the cohesive force required for the methacrylic polymer block (b).

The cohesive force is said to depend on the interaction between molecules (in other words, polarity) and the degree of entanglement, and as the number average molecular weight increases, the entanglement point increases and the cohesive force increases. That is, the number-average molecular weight required for the methacrylic polymer block (b) and M _B, the the entanglement molecular weight of the polymer constituting the methacrylic polymer block (b) of M _B as Mc _B Exemplifying the range, when cohesive force is required, preferably M _B > Mc _B. As a further example, when further cohesive force is required, preferably M _B > 2 × Mc _B. Conversely, when it is desired to achieve a certain cohesive force and creep property, Mc _B <M _B <2 × Mc _B is preferred. The molecular weight between the entanglement points may be referred to Wu et al. (Polym. Eng. And Sci., 1990, Vol. 30, p. 753). For example, the range of the number average molecular weight of the methacrylic polymer block (b) when the cohesive force is required, assuming that the methacrylic polymer block (b) is entirely composed of methyl methacrylate. Then, it is preferable that it is 9200 or more. However, when the unit (c) is contained in the methacrylic polymer block (b), the cohesive force by the unit (c) is imparted, so the number average molecular weight can be set lower than this. From the handling at the time of manufacture, the upper limit of the molecular weight is preferably 200000 or less, more preferably 100000 or less.

  Examples of the methacrylic acid ester constituting the methacrylic polymer block (b) include those exemplified as vinyl monomers copolymerizable with the acrylate ester constituting the acrylic polymer block (a). It is done. These methacrylic acid esters may be used alone or in combination of two or more. Among these, methyl methacrylate is preferable from the viewpoints of cost and availability.

  Examples of the monomer having a functional group serving as a precursor of the unit (c) include monomers similar to the constituent monomers exemplified in the description of the acrylic polymer block (a).

  Examples of vinyl monomers copolymerizable with the methacrylic acid ester constituting the methacrylic polymer block (b) include acrylic acid esters, aromatic alkenyl compounds, vinyl cyanide compounds, conjugated diene compounds, halogens. Examples thereof include an unsaturated compound, an unsaturated dicarboxylic acid compound, a vinyl ester compound, and a maleimide compound.

  Examples of the acrylate ester include monomers similar to the constituent monomers exemplified in the description of the acrylic polymer block (a).

  Aromatic alkenyl compounds, vinyl cyanide compounds, conjugated diene compounds, halogen-containing unsaturated compounds, unsaturated dicarboxylic acid compounds, vinyl ester compounds, and maleimide compounds can be copolymerized in the description of the acrylic polymer block (a). Examples thereof include monomers similar to the constituent monomers exemplified as the vinyl monomers.

  As the vinyl monomer copolymerizable with the methacrylic acid ester, the above-mentioned monomers can be used alone or in combination of two or more. In addition, the polymer of methyl methacrylate is depolymerized by heating. However, acrylic acid ester such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-methoxyethyl acrylate, or a mixture thereof, is depolymerized by heating. Alternatively, depolymerization can be suppressed by copolymerizing styrene or the like. Furthermore, acrylonitrile can be copolymerized for the purpose of improving oil resistance.

The glass transition temperature (Tg _b ) of the methacrylic polymer block (b) is preferably 100 ° C. or higher, more preferably 110 ° C. or higher. When the glass transition temperature is less than 100 ° C., rubber elasticity at a high temperature may decrease.

The glass transition temperature (Tg _b ) of the methacrylic polymer block (b) is determined by obtaining the glass transition temperature of the homopolymer of each monomer constituting the polymer block from the aforementioned third edition of the polymer handbook, Depending on the polymerization ratio of the monomers, the ratio of the monomers constituting the polymer block can be changed according to the Fox formula.

  Specific examples of the methacrylic polymer block (b) include, for example, methacrylic polymer blocks contained in the acrylic block copolymer produced in Production Example 1-2 and Production Example 2-2 described later. .

<Reactive functional group (c ₀ )>
The reactive functional group (c ₀ ) imparts chemical properties and rubber elasticity to the molded product obtained from the thermoplastic elastomer composition according to the present invention while imparting mechanical properties at high temperatures and imparting heat resistance. For this purpose, at least one is introduced per molecule of the block copolymer. Examples of the reactive functional group (c ₀ ) include an epoxy group, a hydroxyl group, an amino group, a carboxyl group, an acid anhydride group, and an isocyanate group.

In the present invention, the reactive functional group (c ₀ ) may act as a reaction point with the acrylic polymer (B), and the reaction point or crosslinking point for the block copolymer to be high molecular weight or crosslinked. It is preferable to act as.

The content of the reactive functional group (c ₀ ) constitutes the cohesive force and reactivity of these functional groups, the structure and composition of the acrylic block copolymer (A), and the acrylic block copolymer (A). Although it is necessary to set appropriately according to the number of blocks and the glass transition temperature, it is preferably 1.0 or more, more preferably 2.0 or more on an average per block copolymer molecule. This is because when the number is less than 1.0, there is a tendency that the high molecular weight due to the bimolecular reaction of the block copolymer and the heat resistance improvement due to crosslinking tend to be insufficient.

Further, from the viewpoint of flexibility, rubber elasticity, and low temperature characteristics, the glass transition temperature Tg _b of the acrylic polymer block (b) after introduction of the reactive functional group (c ₀ ) is 25 ° C. or less, more preferably 0 ° C. Hereinafter, it is more preferable to introduce the reactive functional group (c ₀ ) in a range that is −20 ° C. or lower.

The site of introduction of the reactive functional group (c ₀ ) includes the reaction point of the acrylic block copolymer (A), the cohesive force and glass transition temperature of the block constituting the acrylic block copolymer (A), and It can be appropriately selected according to the required physical properties of the acrylic block copolymer (A). From the viewpoint of improving the heat resistance and heat decomposability of the acrylic block copolymer (A), it is preferable to introduce the reactive functional group (c ₀ ) into the methacrylic polymer block (b). From the viewpoint of imparting rubber elasticity to the block copolymer (A), it is preferable to introduce the reactive functional group (c ₀ ) into the acrylic polymer block (a) as a crosslinkable reaction site (crosslinking point). . In terms of control of the reaction point, heat resistance, rubber elasticity, etc., the reactive functional group (c ₀ ) is either one of the acrylic polymer block (a) or the methacrylic polymer block (b). It is preferable to have.

As the reactive functional group (c ₀ ), a unit (c1) containing an acid anhydride group

や、カルボキシル基を含有する単位（ｃ２）

And a unit containing a carboxyl group (c2)

が、反応性の高さや導入の容易性から好ましい。

Is preferable from the viewpoint of high reactivity and ease of introduction.

R ¹ in the unit (c1) and the unit (c2) is a hydrogen atom or a methyl group, and may be the same or different from each other. q is an integer of 0 to 3, preferably 0 or 1, and more preferably 1. When q exceeds 3, polymerization may become complicated or cyclization to an acid anhydride group may be difficult. Moreover, p is an integer of 0 or 1. When q is 0, p is also 0, and when q is 1 to 3, p is preferably 1.

  Since the unit (c1) and the unit (c2) (unit (c)) have reactivity with a compound having an amino group, a hydroxyl group, an epoxy group, etc., the acrylic block copolymer (A) is converted into a thermoplastic elastomer. (B) It has the characteristics which can be used as a bridge | crosslinking site | part with the compatibilizing agent (C) in the case of blending. Moreover, since the unit (c) has a high glass transition temperature (Tg), when introduced into the methacrylic polymer block (b), which is a hard segment, the heat resistance of the acrylic block copolymer (A). Can be improved.

When the unit (c) is contained in the methacrylic polymer block (b), it is preferable that both R ¹ are methyl groups, and when the unit (c) is contained in the acrylic polymer block (a), R 1 It is preferable that ¹ is a hydrogen atom. When R ¹ is a hydrogen atom when the unit (c) is contained in the methacrylic polymer block (b), or when R ¹ is a methyl group when contained in the acrylic polymer block (a) The difference in the glass transition temperature between the acrylic polymer block (a) and the methacrylic polymer block (b) becomes small, and the rubber elasticity of the acrylic block copolymer (A) tends to decrease. .

  The preferred range of the content of the unit (c) is the cohesive strength of the unit (c), the reactivity with the compatibilizer (C), the structure and composition of the acrylic block copolymer (A), the acrylic block copolymer The acrylic block copolymer varies depending on the number of blocks constituting the coalescence (A), the glass transition temperature, and the site and mode of the acid anhydride group-containing unit (c1) and carboxyl group-containing unit (c2). (A) 0.1-80 weight% is more preferable in the whole, and 0.1-50 weight% is further more preferable. When the content of the unit (c) is less than 0.1% by weight, the compatibility between the acrylic block copolymer (A) and the compatibilizer (C) may be insufficient. On the other hand, when it is less than 0.1% by weight, the heat resistance is not sufficiently improved, and the rubber elasticity at high temperatures may be lowered. On the other hand, if it exceeds 80% by weight, the cohesive force becomes too strong, and the productivity may be lowered.

<Method for producing acrylic block copolymer (A)>
Although it does not specifically limit as a manufacturing method of an acryl-type block copolymer (A), It is preferable to use controlled polymerization. Examples of the controlled polymerization include living anion polymerization, radical polymerization using a chain transfer agent, and recently developed living radical polymerization. Living radical polymerization is preferable from the viewpoint of controlling the molecular weight and structure of the block copolymer and copolymerizing a monomer having a crosslinkable functional group.

  Living polymerisation, in the narrow sense, indicates that the terminal always has activity, but generally also includes pseudo-living polymerization where the terminal is inactive and the terminal is in equilibrium. The living radical polymerization in the present invention is a radical polymerization in which the polymerization terminal is activated and deactivated is maintained in an equilibrium state, and has been actively studied in various groups in recent years. .

  Examples thereof include those using a chain transfer agent such as polysulfide, those using a radical scavenger such as a cobalt porphyrin complex (Journal of American Chemical Society, 1994, 116, 7943) and a nitroxide compound (Macromolecules, 1994). 27, 7228), atom transfer radical polymerization (ATRP) using an organic halide as an initiator and a transition metal complex as a catalyst. In the present invention, there is no particular limitation as to which of these methods is used, but atom transfer radical polymerization is preferred from the viewpoint of ease of control.

In the atom transfer radical polymerization, an organic halide or a sulfonyl halide compound is used as an initiator, and a metal complex having a group metal of group 8, 9, 10, or 11 as a central metal in the periodic table is used as a catalyst ( For example, Matyjazewski et al., Journal of
(American Chemical Society, 1995, 117, 5614, Macromolecules, 1995, 28, 7901, Science, 1996, 272, 866, or Sawamoto et al., Macromolecules, 1995, 21). .

  According to these methods, in general, the polymerization rate is very high, and the radical polymerization is likely to cause a termination reaction such as coupling between radicals, but the polymerization proceeds in a living manner and Mw / Mn = 1 having a narrow molecular weight distribution. A polymer having a molecular weight of about 1 to 1.5 is obtained, and the molecular weight can be freely controlled by the ratio of the monomer and the initiator when charged.

  In the atom transfer radical polymerization method, as the organic halide or sulfonyl halide compound used as an initiator, a monofunctional, difunctional, or polyfunctional compound can be used. These can be used properly according to the purpose. When producing a diblock copolymer, a monofunctional compound is preferable. In the case of producing an aba type triblock copolymer or a babb type triblock copolymer, it is preferable to use a bifunctional compound. In the case of producing a branched block copolymer, it is preferable to use a polyfunctional compound.

  Examples of the monofunctional compound include compounds represented by the following chemical formulas.

C ₆ H ₅ —CH ₂ X
C ₆ H ₅ -CHX-CH _{3
C 6 H 5 -C (CH 3} ) 2 X
R ² —CHX—COOR ^{3
_{R 2 -C (CH 3) X}} -COOR 3
R ² —CHX—CO—R ^{3
_{R 2 -C (CH 3) X}} -CO-R 3
R ² —C ₆ H ₄ —SO ₂ X
(In the formula, C ₆ H ₄ represents a phenylene group. The phenylene group may be any of ortho substitution, meta substitution and para substitution. R ² represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and 6 to 6 carbon atoms. 20 represents an aryl group or an aralkyl group having 7 to 20 carbon atoms, X represents chlorine, bromine or iodine, and R ³ represents a monovalent organic group having 1 to 20 carbon atoms.)
Examples of the bifunctional compound include compounds represented by the following chemical formulas.

X—CH ₂ —C ₆ H ₄ —CH ₂ —X
_{X-CH (CH 3) -C} 6 H 4 -CH (CH 3) -X
_{X-C (CH 3) 2} -C 6 H 4 -C (CH 3) 2 -X
^{X-CH (COOR 4) -} (CH 2) n -CH (COOR 4) -X
_{X-C (CH 3) (} COOR 4) - (CH 2) n -C (CH 3) (COOR 4) -X
^{X-CH (COR 4) -} (CH 2) n -CH (COR 4) -X
^{_{X-C (CH 3) (}} COR 4) - (CH 2) n -C (CH 3) (COR 4) -X
_{X-CH 2 -CO-CH 2} -X
_{X-CH (CH 3) -CO} -CH (CH 3) -X
_{X-C (CH 3) 2} -CO-C (CH 3) 2 X
_{X-CH (C 6 H 5} ) -CO-CH (C 6 H 5) -X
X—CH ₂ —COO— (CH ₂ ) _n —OCO—CH ₂ —X
_{X-CH (CH 3) -COO-} (CH 2) n -OCO-CH (CH 3) -X
_{X-C (CH 3) 2} -COO- (CH 2) n -OCO-C (CH 3) 2 -X
_{X-CH 2 -CO-CO-} CH 2 -X
_{X-CH (CH 3) -CO} -CO-CH (CH 3) -X
_{X-C (CH 3) 2} -CO-CO-C (CH 3) 2 -X
X—CH ₂ —COO—C ₆ H ₄ —OCO—CH ₂ —X
_{X-CH (CH 3) -COO} -C 6 H 4 -OCO-CH (CH 3) -X
_{X-C (CH 3) 2} -COO-C 6 H 4 -OCO-C (CH 3) 2 -X
_{X-SO 2 -C 6 H 4} -SO 2 -X
(In the formula, R ⁴ represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. C ₆ H ₄ represents a phenylene group. The phenylene group is ortho-substituted. C ₆ H ₅ represents a phenyl group, n represents an integer of 0 to 20, and X represents chlorine, bromine or iodine.
Examples of the polyfunctional compound include compounds represented by the following chemical formulas.

C ₆ H ₃ (CH ₂ X) _{3
C 6 H 3 (CH (CH} 3) -X) 3
_{C 6 H 3 (C (CH} 3) 2 -X) 3
_{C 6 H 3 (OCO-CH} 2 X) 3
_{C 6 H 3 (OCO-CH} (CH 3) -X) 3
_{C 6 H 3 (OCO-C} (CH 3) 2 -X) 3
C ₆ H ₃ (SO ₂ X) ₃
(In the formula, C ₆ H ₃ represents a trisubstituted phenyl group. The position of the substituent of the trisubstituted phenyl group may be any of the 1st to 6th positions. X represents chlorine, bromine or iodine.)
In these organic halides or sulfonyl halide compounds that can be used as initiators, the carbon to which the halogen is bonded is bonded to a carbonyl group, a phenyl group, etc., and the carbon-halogen bond is activated to initiate polymerization. . The amount of the initiator to be used may be determined from the ratio with the monomer in accordance with the required molecular weight of the block copolymer. That is, the molecular weight of the block copolymer can be controlled by the number of monomers used per molecule of the initiator.

  The transition metal complex used as a catalyst for atom transfer radical polymerization is not particularly limited, but preferred examples include complexes of monovalent and zerovalent copper, divalent ruthenium, divalent iron or divalent nickel. be able to. Among these, a copper complex is preferable from the viewpoint of cost and reaction control.

Examples of the monovalent copper compound include cuprous chloride, cuprous bromide, cuprous iodide, cuprous cyanide, cuprous oxide, cuprous perchlorate, and the like. . In the case of using a copper compound, 2,2′-bipyridyl and its derivative, 1,10-phenanthroline and its derivative, tetramethylethylenediamine (TMEDA), pentamethyldiethylenetriamine, hexamethyl (2-aminoethyl) Polyamines such as amines can also be added as ligands. A tristriphenylphosphine complex of divalent ruthenium chloride (RuCl ₂ (PPh ₃ ) ₃ ) can also be used as a catalyst.

When a ruthenium compound is used as a catalyst, aluminum alkoxides can also be added as an activator. Further, a divalent iron bistriphenylphosphine complex (FeCl ₂ (PPh ₃ ) ₂ ), a divalent nickel bistriphenylphosphine complex (NiCl ₂ (PPh ₃ ) ₂ ), and a divalent nickel bistributylphosphine A complex (NiBr ₂ (PBu ₃ ) ₂ ) can also be used as a catalyst. The amount of the catalyst, ligand and activator used is not particularly limited, but can be appropriately determined from the relationship between the amount of initiator, monomer and solvent used and the required reaction rate.

  Atom transfer radical polymerization can be carried out without solvent (bulk polymerization) or in various solvents. Examples of the solvent include hydrocarbon solvents such as benzene and toluene, halogenated hydrocarbon solvents such as methylene chloride and chloroform, ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, methanol, ethanol, propanol, isopropanol, Alcohol solvents such as n-butanol and t-butanol, nitrile solvents such as acetonitrile, propionitrile and benzonitrile, ester solvents such as ethyl acetate and butyl acetate, carbonate solvents such as ethylene carbonate and propylene carbonate, etc. These can be used as a mixture of at least one of them. Moreover, when using a solvent, the usage-amount can be suitably determined from the relationship between the viscosity of the whole system, and the required reaction rate (namely, stirring efficiency).

  In addition, the atom transfer radical polymerization is preferably performed at room temperature to 200 ° C, more preferably 50 to 150 ° C. If the atom transfer radical polymerization temperature is lower than room temperature, the viscosity may be too high and the reaction rate may be slow, and if it exceeds 200 ° C., an inexpensive polymerization solvent may not be used.

  As a method of producing a block copolymer by atom transfer radical polymerization, a method of sequentially adding monomers, a method of polymerizing the next block using a polymer synthesized in advance as a polymer initiator, For example, a method of binding the coalescence by reaction can be given. These methods can be used properly according to the purpose. From the viewpoint of simplicity of the production process, a method by sequential addition of monomers is preferred.

  Further, a method for introducing an acid anhydride group-containing unit (c1) and a carboxyl group-containing unit (c2) into the acrylic block copolymer (A) is shown below.

  The method for introducing the acid anhydride group-containing unit (c1) is not particularly limited, but a unit containing a group that serves as a precursor of the acid anhydride group is introduced into the block copolymer, and then the ring. It is preferable to make it. Details of the method will be described below.

  General formula (1):

（式中、Ｒ⁵は水素原子またはメチル基、Ｒ⁶は水素原子、メチル基またはフェニル基を表し、少なくとも１個のメチル基を含むこと以外は互いに同一でも異なっていてもよい）で表される単位を少なくとも１個有するブロック共重合体、即ちアクリル系重合体ブロック（ａ）を構成するアクリル酸エステルとして下記に例示した単量体を用いたブロック共重合体組成物（Ａ）を、好ましくは１８０〜３００℃の温度で、溶融混練して環化させることにより導入することができる。１８０℃より低いと、酸無水物基の生成が不充分となる場合があり、３００℃より高くなると、アクリル系重合体ブロック（ａ）を構成するアクリル酸エステルとして下記に例示した単量体を用いたアクリル系ブロック共重合体（Ａ）自体が分解する場合がある。

Wherein R ⁵ represents a hydrogen atom or a methyl group, R ⁶ represents a hydrogen atom, a methyl group or a phenyl group, and may be the same or different from each other except that it contains at least one methyl group. A block copolymer composition (A) using the monomer exemplified below as a block copolymer having at least one unit, that is, an acrylic ester constituting the acrylic polymer block (a), Can be introduced by melt-kneading and cyclization at a temperature of 180 to 300 ° C. When the temperature is lower than 180 ° C., the acid anhydride group may be insufficiently formed. When the temperature is higher than 300 ° C., the monomers exemplified below as the acrylic acid ester constituting the acrylic polymer block (a) are used. The used acrylic block copolymer (A) itself may decompose.

  The unit represented by the general formula (1) is eliminated and cyclized with an adjacent ester unit at a high temperature to generate, for example, a 6-membered cyclic acid anhydride group (for example, Hatada et al., J.M. Applied Chemistry (JMS PURE APPL. CHEM.), A30 (9 & 10), pages 645-667 (1993)). According to these, in general, a polymer having a bulky ester unit and having β-hydrogen is decomposed at a high temperature to generate a carboxyl group, and then a cyclization occurs, for example, a 6-membered ring or the like. An acid anhydride group is formed. By utilizing these methods, an acid anhydride group can be easily introduced into the acrylic block copolymer (A). Specific examples of the monomer constituting the unit represented by the general formula (1) include t-butyl acrylate, isopropyl acrylate, α, α-dimethylbenzyl acrylate, α-methylbenzyl acrylate, Examples include, but are not limited to, t-butyl methacrylate, isopropyl methacrylate, α, α-dimethylbenzyl methacrylate, α-methylbenzyl methacrylate, and the like. Among these, t-butyl acrylate and t-butyl methacrylate are preferable from the viewpoint of availability, ease of polymerization, and ease of formation of acid anhydride groups.

  Various methods can be applied to the introduction of the carboxyl group-containing unit (c2), and there are no particular limitations. However, the acrylic block copolymer (A) has an acid anhydride group-containing unit (c1). It is preferable to generate a unit (c2) containing a carboxyl group by appropriately adjusting the heating temperature and time according to the type and content of the unit represented by the general formula (1) during the introduction process. This is because it is easy to control the reaction point of the acrylic block copolymer (A) and to introduce the carboxyl group-containing unit (c2) into the acrylic block copolymer (A).

  Therefore, from the viewpoint of the introduction method, the carboxyl group-containing unit (c2) is preferably contained in the same block as the block containing the acid anhydride group-containing unit (c1). From the point of cohesive strength, it is more preferable that it is contained in the methacrylic polymer block (b). That is, by introducing a unit (c2) having a carboxyl group with high Tg and cohesive force into the methacrylic polymer block (b) which is a hard segment, it becomes possible to express rubber elasticity more at high temperatures. It is. Moreover, when the unit (c2) which has a carboxyl group is contained in an acrylic polymer block (a), it is preferable from a compatible point with a compatibilizing agent (C).

<(B) Olefin-based thermoplastic elastomer>
(B) The olefin-based thermoplastic elastomer is not particularly limited, but is a polyolefin composed of a thermoplastic polyolefin homopolymer or copolymer, and an olefin-based rubber or acrylonitrile-butadiene rubber that is completely cross-linked or partially cross-linked. What consists of a combination with (NBR) can be used preferably.

  Polyolefins include thermoplastic and crystalline polyolefin homopolymers and copolymers. Among them, a polypropylene-based component is preferable, and a copolymer containing ethylene in polypropylene is more preferable in order to improve low temperature characteristics.

  As the olefin rubber, an ethylene / propylene rubber excellent in low temperature characteristics and an EPDM rubber which is a terpolymer of a non-conjugated diene are preferable. (A) As the olefin thermoplastic elastomer, an EPDM rubber or NBR in an olefin resin is dynamically used. Cross-linked ones are particularly preferred.

  The (B) olefinic thermoplastic elastomer of the present invention preferably has a Shore A hardness of 50 to 90 at 23 ° C., more preferably 65 to 85. Such olefin-based thermoplastic elastomers are commercially available under trade names such as Santoprene and GEOLLAST (both manufactured by Advanced Elastomer Systems), and can be easily obtained from the market.

<(C) Compatibilizer>
Although the compatibilizing agent used in the present invention is not particularly limited, an acrylic block copolymer (A) is used to better compatibilize the acrylic block copolymer (A) and the olefinic thermoplastic elastomer (B). An olefinic thermoplastic resin (modified polyolefin) containing an epoxy group that reacts with the unit (c) such as polymethacrylic anhydride) is preferred. Examples thereof include commercially available copolymers of ethylene and glycidyl methacrylate, or ethylene and glycidyl methacrylate having methyl acrylate, polypropylene grafted with glycidyl methacrylate, and the like. The content of glycidyl methacrylate in the modified polyolefin resin is preferably 0.05 wt% to 50 wt%, more preferably 0.1 wt% to 20 wt%. If the glycidyl methacrylate content is less than 0.05% by weight, the compatibility between the acrylic block copolymer (A) and the olefinic thermoplastic elastomer (B) may be insufficient, and the tensile strength may deteriorate. . When the content of glycidyl methacrylate is more than 50% by weight, the cohesiveness of the acrylic block copolymer (A) and the olefinic thermoplastic elastomer (B) becomes too strong, and the tensile elongation may be lowered. These modified polyolefin resins are, for example, commercially available product names such as Bond First (Sumitomo Chemical Co., Ltd.) and Modiper (Nippon Yushi Co., Ltd.), and can be easily obtained from the market.

<(D) Lubricant>
The lubricant used in the present invention is not particularly limited. For example, silicone oil, oleic amide lubricant, erucic amide lubricant, stearamide amide lubricant, hydrocarbon lubricant, fatty acid lubricant, ester lubricant, alcohol Examples thereof include a system lubricant and a metal soap, and a silicone oil is preferable from the viewpoint of heat resistance. Examples of the silicone oil include dimethyl silicone oil, phenylmethyl silicone oil, fluorosilicone oil, tetramethyltetraphenyltrisiloxane, and modified silicone oil. Among these, dimethyl silicone oil is preferable from the viewpoint of cost.

  The kinematic viscosity [JIS K 2283, 25 ° C.] of the silicone oil is preferably 10 to 30,000 cSt, more preferably 50 to 10,000 cSt, and still more preferably 100 to 5,000 cSt. Moreover, it is preferable that it is 0.05-5 weight part with respect to 100 weight part of acrylic block copolymers (A), and, more preferably, it is 0.1-2 weight part. If it is 0.05 parts or less, the friction coefficient is not reduced, and the wear resistance is not improved. On the other hand, if it is 5 parts by weight or more, the elastic modulus at high temperature is lowered due to the plasticizing effect, which is not preferable.

<(E) Polypropylene resin>
The polypropylene resin used in the present invention is not particularly limited, but a homopolypropylene resin is preferable from the viewpoint of oil resistance and heat resistance. The addition amount is preferably 50 parts by weight or less, more preferably 30 parts by weight or less, and particularly preferably 20 parts by weight or less with respect to 100 parts by weight of the acrylic block copolymer (A). Exceeding 50 parts by weight is not preferable because the tensile permanent strain of the molded article increases.

<Thermoplastic elastomer composition>
The thermoplastic elastomer composition of the present invention comprises (A) an acrylic block copolymer, (B) an olefin thermoplastic elastomer, (C) a compatibilizing agent, (D) a lubricant, and (E) a polypropylene resin. It is characterized by including. What is necessary is just to determine the compounding quantity of each component suitably according to the characteristic of a product, for example, in the case of the sealing product for motor vehicles, with respect to 100 weight part of acrylic block copolymers (A), an olefinic thermoplastic elastomer (B ) 50 to 600 parts by weight, further 200 to 600 parts by weight, particularly 400 parts by weight, (C) 5 to 50 parts by weight of compatibilizer, (D) 0.05 to 5 parts by weight of lubricant, (E) polypropylene-based It is preferable to consist of 5-50 weight part of resin. When each content is within the above range, a molded article having good wear resistance, low temperature property, heat resistance, and oil resistance can be obtained.

  These thermoplastic elastomer compositions measure the acrylic block copolymer (A), the olefinic thermoplastic elastomer (B), the compatibilizer (C), and the lubricant (D) before being actually molded. However, from the viewpoint of handling, uniformity of kneading, etc., it is preferable to pelletize before molding. Below, the pelletization is demonstrated.

  The method for pelletizing the thermoplastic elastomer composition of the present invention is not particularly limited, but it is heated at an appropriate temperature using a known apparatus such as a Banbury mixer, roll mill, kneader, single-screw or multi-screw extruder. However, it can be shaped into a pellet by mechanically kneading.

  The kneading temperature can be adjusted according to the melting temperature of the acrylic block copolymer (A), olefinic thermoplastic elastomer (B), compatibilizer (C), polypropylene resin (E) used, etc. Well, for example, it can be pelletized by melt-kneading at 180 to 300 ° C. The blending method of the lubricant (D) may be added during kneading, but the acrylic block copolymer (A), olefinic thermoplastic elastomer (B), compatibilizer (C), polypropylene resin (E) can also be added later to the kneaded pellets.

  The composition of the present invention includes stabilizers (anti-aging agents, light stabilizers, ultraviolet absorbers, etc.), flexibility imparting agents, flame retardants, mold release agents, antistatic agents, antibacterial antifungal agents, depending on the required properties. An agent or the like may be added. These additives may be appropriately selected and used according to the required physical properties, workability, and the like.

  Examples of stabilizers (anti-aging agent, light stabilizer, ultraviolet absorber, etc.) include, but are not limited to, the following compounds.

  Antiaging agents include phenyl α-naphthylamine (PAN), octyldiphenylamine, N, N′-diphenyl-p-phenylenediamine (DPPD), N, N′-di-β-naphthyl-p-phenylenediamine (DNPD). N- (1,3-dimethyl-butyl) -N′-phenyl-p-phenylenediamine, N-phenyl-N′-isopropyl-p-phenylenediamine (IPPN), N, N′-diallyl-p-phenylene Diamine, phenothiazine derivative, diallyl-p-phenylenediamine mixture, alkylated phenylenediamine, 4,4′-α, α-dimethylbenzyldiphenylamine, p, p-toluenesulfonylaminodiphenylamine, N-phenyl-N ′-(3- Methacryloyloxy-2-hydropropyl) -p-pheny Diamines, diallylphenylenediamine mixtures, diallyl-p-phenylenediamine mixtures, N- (1-methylheptyl) -N-phenyl-p-phenylenediamine, amine-based antioxidants such as diphenylamine derivatives, 2-mercaptobenzimidazole (MBI) ) Imidazole anti-aging agents, phenolic anti-aging agents such as 2,6-di-t-butyl-4-methylphenol, phosphate anti-aging agents such as nickel diethyl-dithiocarbamate, triphenyl phosphite Secondary anti-aging agents such as

  Examples of light stabilizers and ultraviolet absorbers include 4-t-butylphenyl salicylate, 2,4-dihydroxybenzophenone, 2,2′dihydroxy-4-methoxybenzophenone, ethyl-2-cyano-3,3′-diphenyl. Acrylate, 2-ethylhexyl-2-diano-3,3′-diphenyl acrylate, 2-hydroxy-5-chlorobenzophenone, 2-hydroxy-4-methoxybenzophenone-2-hydroxy-4-octoxybenzophenone, monoglycol salicy Rate, oxalic acid amide, 2,2 ′, 4,4′-tetrahydroxybenzophenone and the like. These stabilizers may be used alone or in combination of two or more.

  Examples of the flexibility-imparting agent include plasticizers, softeners, oligomers, oils (animal oil, vegetable oil, etc.) usually used in thermoplastic resins and rubbers, petroleum fractions (kerosene, light oil, heavy oil, naphtha, etc.). However, it is preferable to use an acrylic block copolymer (A), an olefinic thermoplastic elastomer (B), and a compatibilizer (C) that are excellent in affinity. Among these, low-volatility plasticizers with low heat loss are adipic acid derivatives, phthalic acid derivatives, glutaric acid derivatives, trimellitic acid derivatives, pyromellitic acid derivatives, polyester plasticizers, glycerin derivatives, epoxy derivatives polyester polymerized plastics. An agent, a polyether polymerization type plasticizer and the like are preferably used.

  Examples of the softener include process oils such as petroleum process oils such as paraffinic oils, naphthenic process oils, and aromatic process oils.

  Examples of the plasticizer include dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate, di- (2-ethylhexyl) phthalate, diheptyl phthalate, diisodecyl phthalate, di-n-octyl phthalate, and phthalic acid. Phthalic acid derivatives such as diisononyl, ditridecyl phthalate, octyldecyl phthalate, butyl benzyl phthalate, dicyclohexyl phthalate; isophthalic acid derivatives such as dimethyl isophthalate; tetrahydrophthal such as di- (2-ethylhexyl) tetrahydrophthalic acid Acid derivatives; dimethyl adipate, dibutyl adipate, di-n-hexyl adipate, di- (2-ethylhexyl) adipate, dioctyl adipate, isononyl adipate, diisodecyl adipate, dibutyl diglycol adipate, etc. Adipic acid derivatives; azelaic acid derivatives such as di-2-ethylhexyl azelate; sebacic acid derivatives such as dibutyl sebacate; dodecanedioic acid derivatives; maleic acid derivatives such as dibutyl maleate and di-2-ethylhexyl maleate; fumaric acid Fumaric acid derivatives such as dibutyl; p-oxybenzoic acid derivatives such as 2-ethylhexyl p-oxybenzoate; trimellitic acid derivatives such as tris-2-ethylhexyl trimellitic acid; pyromellitic acid derivatives; citric acid derivatives such as acetyltributyl citrate Itaconic acid derivative; oleic acid derivative; ricinoleic acid derivative; stearic acid derivative; other fatty acid derivative; sulfonic acid derivative; phosphoric acid derivative; glutaric acid derivative; dibasic acid such as adipic acid, azelaic acid, phthalic acid and glycol Polyester plasticizers that are polymers with monohydric alcohol, etc., glycol derivatives, glycerin derivatives, paraffin derivatives such as chlorinated paraffins, epoxy derivatives polyester polymerized plasticizers, polyether polymerized plasticizers, ethylene carbonate, propylene Examples thereof include carbonate derivatives such as carbonate, benzenesulfonic acid derivatives such as N-butylbenzeneamide, and the like, but are not limited to these, such as those widely marketed as plasticizers for rubber or thermoplastic resins. Various plasticizers can be used.

  Commercially available plasticizers include Thiocol TP (manufactured by Morton), Adekasizer O-130P, C-79, UL-100, P-200, RS-735 (Asahi Denka Kogyo Co., Ltd.), Sunsosizer N-400 (manufactured by Shin Nippon Rika Co., Ltd.), BM-4 (manufactured by Daihachi Chemical Industry Co., Ltd.), EHPB (manufactured by Ueno Pharmaceutical Co., Ltd.), UP-1000 (manufactured by Toagosei Co., Ltd.), etc. Can be given.

  Examples of the oil include vegetable oils such as castor oil, cottonseed oil, sesame oil, rapeseed oil, soybean oil, palm oil, coconut oil, peanut oil, pine oil, tall oil, sesame oil, and camellia oil.

  Examples of other flexibility imparting agents include polybutene oil, spindle oil, machine oil, tricresyl phosphate, and the like.

  Examples of the flame retardant include, but are not limited to, triphenyl phosphate, tricresyl phosphate, decabromobiphenyl, decabromobiphenyl ether, and antimony trioxide. These flame retardants may be used alone or in combination of two or more.

  The composition of the present invention is molded by molding the composition by any molding method such as extrusion molding, compression molding, blow molding, calender molding, vacuum molding, foam molding, injection molding, injection blow, and the like. Can be done. Of these, injection molding is preferred because it is simple.

  As conditions for molding the thermoplastic elastomer composition according to the present invention, for example, in the case of an injection molding method, the cylinder temperature is generally 150 to 230 ° C., the nozzle temperature is 180 to 240 ° C., the injection speed is low, and the cooling time is 15 to 15. Examples include molding conditions such as 60 seconds, mold temperature: 10 to 80 ° C.

  A molded article produced by such a method has excellent low temperature characteristics, oil resistance, heat resistance, tensile characteristics, and abrasion resistance. Therefore, the composition according to the present invention can be suitably used for automotive parts, and is excellent in simplification of the molding process and recyclability as compared with, for example, conventional vulcanized rubber systems.

  Applications of the thermoplastic elastomer composition of the present invention include, for example, molded products for automobiles, household electrical appliances, and office electrical appliances. Specifically, oil seals, various oil seals such as reciprocating oil seals, various packings such as gland packing, lip packing, squeeze packing, suspension dust cover, suspension / tie rod dust cover, stabilizer / die rod dust cover, etc. Various dust covers, resin intake manifold gaskets, gaskets for throttle bodies, gaskets for power steering vane pumps, gaskets for head covers, gaskets for water heater self-contained pumps, filter gaskets, gaskets for pipe fittings (ABS & HBB), top cover gaskets for HDDs, HDD connector gasket, cylinder head gasket combined with metal, car cooler compressor gasket, gasket around the engine , AT separate plates, various gaskets such as general-purpose gaskets (industrial sewing machines, nailing machines, etc.), needle valves, plunger valves, water / gas valves, brake valves, drinking valves, safety valves for aluminum electrolytic capacitors, etc. Valves, vacuum boosters, water / gas diaphragms, seal washers, bore plugs, high-precision stoppers and other stoppers mainly with buffer performance, plug tube seals, injection pipe seals, oil receivers, brake drum seals , Precision seal rubber such as shading seal, plug seal, connector seal, keyless entry cover and the like. In addition, various weather strips such as door weather strips for automobiles, trunk seals, glass run channels, accelerator pedals, and boot parts such as steering rack boots, strut boots, constant velocity joint boots, and the like can be cited. In particular, a molded article obtained by injection molding is useful as an automobile, household electrical appliance or office electrical appliance molded product.

  Next, the composition of the present invention will be described in more detail based on examples, but the present invention is not limited only to these examples.

  In the following, EA, BA, MEA, MMA and TBMA mean ethyl acrylate, n-butyl acrylate, 2-methoxyethyl acrylate, methyl methacrylate and t-butyl methacrylate, respectively.

  The molecular weight of the polymer is a polystyrene-converted molecular weight obtained by GPC measurement using a polystyrene gel column using chloroform as a mobile phase using the GPC analyzer shown below.

<Test method>
(Molecular weight)
The molecular weight of the acrylic block copolymer was measured with a GPC analyzer (system: GPC system manufactured by Waters, column: Shodex K-804 (polystyrene gel) manufactured by Showa Denko KK). The molecular weight in terms of polystyrene was determined using chloroform as the mobile phase.

(6-membered cyclic acid anhydride group conversion analysis)
Confirmation of the 6-membered cyclic acid anhydride group conversion reaction of the acrylic block copolymer was performed by infrared spectrum analysis (manufactured by Shimadzu Corporation, using FTIR-8100) and nuclear magnetic resonance analysis (manufactured by BRUKER, AM400). Use).
As a nuclear magnetic resonance analysis solvent, a block body having a carboxylic acid ester structure was analyzed using deuterated chloroform as a measurement solvent together with a block body having a 6-membered cyclic acid anhydride structure.

(hardness)
In accordance with JIS K6301, the hardness at 23 ° C. (JIS A) was measured.

(Tensile properties)
According to the method described in JIS K7113, measurement was performed using an autograph AG-10TB type manufactured by Shimadzu Corporation. The measurement was performed at n = 3, and the average values of strength (MPa), elastic modulus (MPa) and elongation (%) when the test piece was broken were adopted. A test piece having a shape of 2 (1/3) shape and a thickness of about 2 mm was used. The test was conducted at 23 ° C. and a test speed of 500 mm / min. In principle, the test piece was conditioned at a temperature of 23 ° C. ± 2 ° C. and a relative humidity of 50 ± 5% for 48 hours or more before the test.

(Oil resistance)
In accordance with ASTM D638, ASTM Oil No. maintained at 100 ° C. The molded product of the composition was immersed in 3 for 72 hours, and the weight change rate (% by weight) was determined.

(Compression set)
In accordance with JIS K6301, the cylindrical formed body was held at 100 ° C. for 72 hours under the condition of a compression rate of 25%, and left at room temperature for 30 minutes, and then the thickness of the molded body was measured, and the residual strain was calculated. It means that all of the distortion is recovered at 0% compression set, and that no distortion is recovered at 100% compression set.

(Coefficient of friction)
Based on JIS K7125, the dynamic friction coefficient was measured using a HEIDON tester under the conditions of 23 ° C., load 200 g, friction distance 70 mm, and test speed 100 mm / min.

(Abrasion resistance)
The same material was brought into contact with an area of 1 cm ² , and the wear surface was visually observed using a HEIDON tester under the conditions of 23 ° C., load 500 g, wear distance 50 mm, test speed 5000 mm / min, and 1000 reciprocations. When abrasion was seen, it was determined to be “x”, and when abrasion was not observed, it was determined to be “good”.

<Production example of acrylic block copolymer>
(Production Example 1-1) (MMA-co-TBMA) -b- (BA-co-MEA) -b- (MMA-co-TBMA) (MMA / TBMA = 58/42 mol%, BA / MEA = 66 / 34 mol%, (BA-co-MEA) / (MMA-co-TBMA) = 65/35 wt%) type acrylic block copolymer (MMA-co-TBMA) is a polymer block composed of MMA and TBA. (BA-co-MEA) means a polymer block composed of BA and MEA, and (MMA-co-TBMA) -b- (BA-co-MEA) -b- (MMA-co-TBMA) is , (MMA-co-TBMA) polymer block and (BA-co-MEA) polymer block means a block copolymer arranged in this order (hereinafter referred to as “precursor 1”) After the inside of the polymerization vessel of a 500 L reactor equipped with a stirrer capable of heating and cooling was purged with nitrogen, 840.1 g (5.9 mol) of copper bromide was weighed and 12 L of acetonitrile (nitrogen bubbling) was added. After heating and stirring at 70 ° C. for 30 minutes, 421.7 g (1.17 mol) of diethyl 2,5-dibromoadipate initiator, 41.4 L (288.9 mol) BA, and 18.6 L (144.5 mol) MEA were added. It was. The mixture was heated and stirred at 85 ° C., and 0.1 L (0.59 mol) of ligand diethylenetriamine was added to initiate polymerization.

  About 0.2 ml of the polymerization solution was sampled at regular intervals from the start of polymerization, and the conversion rate of BA was determined by gas chromatogram analysis of the sampling solution. The polymerization rate was controlled by adding diethylenetriamine as needed. When the conversion rate of BA was 94% and the conversion rate of MEA was 96%, TBMA 24.9L (153.8 mol), MMA 24.7L (230.8 mol), copper chloride 580 g (5.9 mol), butyl acetate 1 2 L (9.1 mol) and 122.8 L of toluene (nitrogen bubbled) were added. Similarly, conversion rates of TBMA and MMA were determined. When the conversion rate of TBMA was 61% and the conversion rate of MMA was 56%, 80 L of toluene was added and the reactor was cooled in a water bath to complete the reaction.

The reaction solution was diluted with 115 L of toluene, 1337 g of p-toluenesulfonic acid monohydrate was added and stirred at room temperature for 3 hours, and then the solid was removed using a bag filter (HAYWARD). To the polymer solution obtained, 1642 g of an adsorbent (trade name KYOWARD 500SH; manufactured by Kyowa Chemical Co., Ltd.) was added and stirred for another 3 hours at room temperature. The adsorbent was filtered using a bag filter to obtain a colorless and transparent polymer solution. Obtained. This solution was dried using a horizontal evaporator (heat transfer area: 1 m ² ) to remove the solvent and residual monomer, thereby obtaining the target block copolymer 2A40T6.5.

  When the GPC analysis of the obtained block copolymer was conducted, the number average molecular weight (Mn) was 93700, and molecular weight distribution (Mw / Mn) was 1.36.

(Production Example 1-2) [Six-membered cyclic acid anhydride reaction of precursor 1 and characteristic evaluation]
700 g of the block copolymer (precursor 1) obtained in Production Example 1-1 and 1.4 g of a phenolic antioxidant (trade name Irganox 1010, manufactured by Ciba Specialty Chemicals Co., Ltd.) And melt kneading for 20 minutes at 70 rpm using a pressure kneader (manufactured by Moriyama Co., Ltd., DS1-5MHB-E type kneader) to obtain the target 6-membered cyclic acid anhydride group-containing block copolymer (obtained) The polymer was hereinafter referred to as polymer 1). The block of the polymer obtained by the pressure kneader was freeze-pulverized with liquid nitrogen and a pulverizer to obtain the block copolymer pellets.

The conversion of the t-butyl ester moiety to a 6-membered cyclic acid anhydride group could be confirmed by IR (infrared absorption spectrum) analysis and ¹³ C-NMR (nuclear magnetic resonance spectrum) analysis.

That is, in the IR analysis, it was confirmed that an absorption spectrum derived from an acid anhydride group was observed around 1800 cm ⁻¹ after conversion. ^{In the 13} C-NMR analysis, it was confirmed that the 82 ppm signal derived from the methine carbon of the t-butyl group and the 28 ppm signal derived from the methyl carbon disappeared after the conversion.

(Production Example 2-1) (MMA-co-TBMA) -b- (BA-co-EA-co-MEA) -b- (MMA-co-TBMA) (MMA / TBMA = 51/49 mol%, BA / EA / MEA = 35/44/21 mol%, (BA-co-EA-co-MEA) / (MMA-co-TBMA) = 61/39 wt%) type acrylic block copolymer ((MMA-co- (TBMA) means a polymer block composed of MMA and TBA, (BA-co-EA-co-MEA) means a polymer block composed of BA, EA and MEA, and (MMA-co-TBMA) -b- (BA-co-EA-co-MEA) -b- (MMA-co-TBMA) has (MMA-co-TBMA) polymer block and (BA-co-EA-co-MEA) polymer block. This This means a block copolymer arranged in order.Hereinafter, described as “precursor 2”) Using a 500 L reactor equipped with a stirrer capable of heating and cooling, 634 g (1.76 mol) of diethyl 2,5-dibromoadipate , BA 33.8 L (235.5 mol), EA 32.1 L (296 mol), MEA 18.2 L (141.3 mol) were charged at a charging ratio, BA conversion was 96%, and EA conversion was 95. TBMA 33.4 L (206 mol) and MMA 22.0 L (206.1 mol) were added when the conversion rate of MEA was 97%. The reaction was terminated when the conversion rate of TBMA was 91% and the conversion rate of MMA was 94%. Otherwise, the production was carried out in the same manner as in Production Example 1-1 to obtain the intended acrylic block copolymer (3A50T6.1).

  When the GPC analysis of the obtained acrylic block copolymer (3A50T6.1) was performed, the number average molecular weight (Mn) was 104400, and molecular weight distribution (Mw / Mn) was 1.31.

(Production Example 2-2) [Six-membered cyclic acid anhydride reaction of precursor 2 and characterization]
For 100 parts by weight of the acrylic block copolymer (precursor 2) obtained in Production Example 2-1, 0.6 part by weight of Irganox 1010 (manufactured by Ciba Specialty Chemicals) is blended, Using a twin screw extruder with a vent (44 mm, L / D = 42.25) (manufactured by Nippon Steel Works), extrusion kneading at a rotation speed of 300 rpm and a set temperature of 240 ° C., the target acid anhydride group-containing acrylic A system block copolymer (the obtained polymer is hereinafter referred to as polymer 2) was obtained.

  When the GPC analysis of the obtained block copolymer polymer 2 was conducted, the number average molecular weight (Mn) was 93700, and molecular weight distribution (Mw / Mn) was 1.36.

  At this time, an underwater cut pelletizer (CLS-6-8.1 COMPACT LAB SYSTEM manufactured by GALA INDUSTRIES INC.) Is connected to the tip of the twin screw extruder, and Alfflow H- is used as an anti-adhesive agent in the circulating water of the underwater cut pelletizer. By adding 50ES (Nippon Yushi Co., Ltd.), spherical pellets without stickiness were obtained.

Example 1
952.4 g of acrylic block copolymer (Polymer 1) obtained in Production Example 1-2, 3809.5 g of olefinic thermoplastic elastomer (trade name: Santoprene 111-80; manufactured by Advanced Elastomer Systems), compatibilizing 238.1 g of an agent (ethylene-glycidyl methacrylate-methacrylate) was thoroughly mixed by hand blending so as to be uniformly dispersed. Then, this was melt-kneaded with a twin screw extruder “TEX30HSS-25.5PW-2V” (manufactured by Nippon Steel). The kneading conditions are as follows: Rotational speed: 280 rpm, Chopper for hopper installation part side cylinder and C7 for die head side barrel: C1 to C3: 80 ° C., C4: 100 ° C., C5: 120 ° C., C6: 200 degreeC, C7: 220 degreeC, and the die head part were 220 degreeC. The extruded strand was pelletized with a pelletizer “SCF-100” (manufactured by Isuzu Chemical Industries Co., Ltd.) so as to facilitate injection molding. To 4 kg of pellets obtained by drying at 80 ° C. for 3 hours or more, 7.6 g of polydimethylsiloxane (trade name: TSF451-1000 manufactured by GE Toshiba Silicones) was sufficiently mixed by hand blending. Injection molding is performed with an injection molding machine “IS-80EPN” (manufactured by Toshiba Machine Co., Ltd.) with a clamping pressure of 80 TON at a cylinder temperature of 180 ° C., a nozzle temperature of 210 ° C., an injection speed of 10%, a cooling time of 30 seconds, and a mold temperature of 40 ° C. A flat plate of 120 × 120 × 2 mm was obtained, and a low temperature embrittlement temperature, a tensile elastic modulus of −45 ° C., a tensile property of 23 ° C., oil resistance, a compression set, a friction coefficient, and an abrasion property were measured. In addition, the hardness of the three obtained flat plates was measured. The results are shown in Table 1.

(Example 2)
934.6 g of the acrylic block copolymer (polymer 2) obtained in Production Example 2-2, 3738.3 g of an olefinic thermoplastic elastomer (trade name: Santoprene 111-73; manufactured by Advanced Elastomer Systems), homopolypropylene (Product name: Mitsui Polypro J105G, manufactured by Mitsui Chemicals) 93.5 g and a compatibilizer (ethylene-glycidyl methacrylate-methacrylate) 233.6 g were sufficiently mixed by hand blending so as to be uniformly dispersed. The kneading conditions were C1 to C3: 80 ° C., C4: 100 ° C., C5: 120 ° C., C6: 200 ° C., C7: 220 ° C., die head: 220 ° C., rotation speed: 280 rpm, vented twin screw extruder “TEX30HSS-25” .5PW-2V "(Nippon Steel Works). The extruded strand was pelletized with a pelletizer “SCF-100” (manufactured by Isuzu Chemical Industries Co., Ltd.) so as to facilitate injection molding. To 4 kg of pellets obtained by drying at 80 ° C. for 3 hours or more, 7.5 g of polydimethylsiloxane (trade name: TSF451-1000 manufactured by GE Toshiba Silicone) was sufficiently mixed by hand blending. Injection molding is performed with an injection molding machine “IS-80EPN” (manufactured by Toshiba Machine Co., Ltd.) with a clamping pressure of 80 TON at a cylinder temperature of 180 ° C., a nozzle temperature of 210 ° C., an injection speed of 10%, a cooling time of 30 seconds, and a mold temperature of 40 ° C. A flat plate of 120 × 120 × 2 mm was obtained, and a low temperature embrittlement temperature, a tensile elastic modulus of −45 ° C., a tensile property of 23 ° C., oil resistance, a compression set, a friction coefficient, and an abrasion property were measured. In addition, the hardness of the three obtained flat plates was measured. The results are shown in Table 1.

(Comparative Example 1)
952.4 g of acrylic block copolymer (Polymer 1) obtained in Production Example 1-2, 3809.5 g of olefinic thermoplastic elastomer (trade name: Santoprene 111-80; manufactured by Advanced Elastomer Systems), compatibilizing 238.1 g of an agent (ethylene-glycidyl methacrylate-methacrylate) was thoroughly mixed by hand blending so as to be uniformly dispersed. The kneading conditions were C1 to C3: 80 ° C., C4: 100 ° C., C5: 120 ° C., C6: 200 ° C., C7: 220 ° C., die head: 220 ° C., rotation speed: 280 rpm, vented twin screw extruder “TEX30HSS-25” .5PW-2V "(Nippon Steel Works). The extruded strand was pelletized with a pelletizer “SCF-100” (manufactured by Isuzu Chemical Industries Co., Ltd.) so as to facilitate injection molding. The pellets obtained by drying at 80 ° C. for 3 hours or more were subjected to an injection molding machine “IS-80EPN” (manufactured by Toshiba Machine Co., Ltd.) with a clamping pressure of 80 TON, a cylinder temperature of 180 ° C., a nozzle temperature of 210 ° C., an injection speed of 10%, Injection molding at a cooling time of 30 seconds and a mold temperature of 40 ° C. to obtain a flat plate of 120 × 120 × 2 mm, low temperature embrittlement temperature, −45 ° C. tensile modulus, 23 ° C. tensile properties, oil resistance, compression set, Coefficient of friction and wear were measured. In addition, the hardness of the three obtained flat plates was measured. The results are shown in Table 1.

(Comparative Example 2)
934.6 g of the acrylic block copolymer (polymer 2) obtained in Production Example 2-2, 3738.3 g of an olefinic thermoplastic elastomer (trade name: Santoprene 111-73; manufactured by Advanced Elastomer Systems), homopolypropylene (Product name: Mitsui Polypro J105G, manufactured by Mitsui Chemicals) 93.5 g and a compatibilizer (ethylene-glycidyl methacrylate-methacrylate) 233.6 g were sufficiently mixed by hand blending so as to be uniformly dispersed. The kneading conditions were C1 to C3: 80 ° C., C4: 100 ° C., C5: 120 ° C., C6: 200 ° C., C7: 220 ° C., die head: 220 ° C., rotation speed: 280 rpm, vented twin screw extruder “TEX30HSS-25” .5PW-2V "(Nippon Steel Works). The extruded strand was pelletized with a pelletizer “SCF-100” (manufactured by Isuzu Chemical Industries Co., Ltd.) so as to facilitate injection molding. The pellets obtained by drying at 80 ° C. for 3 hours or more were subjected to an injection molding machine “IS-80EPN” (manufactured by Toshiba Machine Co., Ltd.) with a clamping pressure of 80 TON, a cylinder temperature of 180 ° C., a nozzle temperature of 210 ° C., an injection speed of 10%, Injection molding at a cooling time of 30 seconds and a mold temperature of 40 ° C. to obtain a flat plate of 120 × 120 × 2 mm, low temperature embrittlement temperature, −45 ° C. tensile modulus, 23 ° C. tensile properties, oil resistance, compression set, Coefficient of friction and wear were measured. In addition, the hardness of the three obtained flat plates was measured. The results are shown in Table 1.

(Comparative Example 3)
5000 g of the acrylic block copolymer (Polymer 2) obtained in Production Example 2-2 was dried at 80 ° C. for 3 hours or more, and 50 g of polydimethylsiloxane (trade name: TSF451-1000 manufactured by GE Toshiba Silicones) was handed. Mix well in blend. Injection molding of pellets with an injection molding machine (IS-80EPN; manufactured by Toshiba Machine Co., Ltd.) with a clamping pressure of 80 TON at a cylinder temperature of 240 ° C, a nozzle temperature of 240 ° C, an injection speed of 10%, a cooling time of 30 seconds, and a mold temperature of 40 ° C A 120 × 120 × 2 mm flat plate was obtained, and the low temperature embrittlement temperature, the tensile elastic modulus at −45 ° C., the tensile properties at 23 ° C., the oil resistance, the compression set, the friction coefficient, and the wear resistance were measured. In addition, the hardness of the three obtained flat plates was measured. The results are shown in Table 1.

As is clear from Table 1 (Examples 1 and 2 and Comparative Examples 1 and 2), an acrylic block copolymer containing a lubricant (polydimethylsiloxane) shown in Examples 1 and 2 and an olefinic thermoplastic elastomer A molded article made of a thermoplastic elastomer composition of a compatibilizing agent is an acrylic block copolymer, an olefinic thermoplastic elastomer and a thermoplastic elastomer composition of a compatibilizing agent that do not contain a lubricant as shown in Comparative Examples 1, 2, and 3. It can be seen that the coefficient of friction is smaller than that of a molded article made of a product and an acrylic block copolymer, the wear resistance is good, and the flexibility and heat resistance at low temperatures are good.

Claims (12)

(A) an acrylic block copolymer comprising an acrylic polymer block (a) and a methacrylic polymer block (b);
(B) an olefinic thermoplastic elastomer,
A thermoplastic elastomer composition comprising (C) a compatibilizer and (D) a lubricant. (A) For 100 parts by weight of the acrylic block copolymer,
(B) 50 to 600 parts by weight of an olefinic thermoplastic elastomer,
(C) 5-50 parts by weight of a compatibilizer,
The thermoplastic elastomer composition according to claim 1, comprising 0.05 to 10 parts by weight of (D) a lubricant.   Furthermore, the thermoplastic elastomer of Claim 1 or 2 containing (E) polypropylene resin. The thermoplastic elastomer composition according to any one of claims 1 to 3, wherein the acrylic block copolymer (A) has a reactive functional group (c ₀ ). The unit (c1) in which the reactive functional group (c ₀ ) contains an acid anhydride group

And / or a unit containing a carboxyl group (c2)

(In the formulas of units (c1) and (c2), R ¹ is a hydrogen atom or a methyl group, and may be the same or different from each other. P is an integer of 0 or 1, and q is an integer of 0 to 3. The thermoplastic elastomer composition according to claim 4, wherein   6. The thermoplastic elastomer composition according to claim 5, wherein the acrylic block copolymer (A) contains 0.1 to 50% by weight of a unit (c2) containing a carboxyl group.   The acrylic block copolymer (A) contains 50 to 90% by weight of the acrylic polymer block (a) and 50 to 10% by weight of the methacrylic polymer block (b). The thermoplastic elastomer composition according to any one of claims 1 to 6.   The thermoplastic elastomer composition according to any one of claims 1 to 7, wherein the acrylic block copolymer (A) is a block copolymer produced by atom transfer radical polymerization.   The thermoplastic elastomer according to any one of claims 1 to 8, wherein the olefinic thermoplastic elastomer (B) is obtained by dynamically crosslinking an EPDM rubber or an acrylonitrile-butadiene rubber in the presence of an olefin resin. Composition.   The thermoplastic elastomer composition according to any one of claims 1 to 9, wherein the compatibilizing agent (C) is an olefin-based thermoplastic resin containing an epoxy group.   The thermoplastic elastomer composition according to any one of claims 1 to 10, wherein the lubricant (D) is a silicone-based oil. A molded article for automobiles, household electrical appliances, or office electrical appliances obtained by injection molding the thermoplastic elastomer composition according to any one of claims 1 to 11.