JP2007182482A - Thermoplastic elastomer composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acrylic block copolymer composition maintaining weatherability, oil resistance, chemical resistance, adhesion, flexibility and abrasion resistance each characteristic of acrylic block copolymer, and excellent in melt fluidity under molding and heat resistance. <P>SOLUTION: The acrylic block copolymer composition is a thermoplastic elastomer composition comprising (A) an acrylic block copolymer composed of methacrylic polymer blocks (a) and acrylic polymer blocks (b) and having on average per molecule one or more hydroxy groups and (B) an acrylic polymer having on average per molecule 1.1 or more epoxy groups. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermoplastic elastomer composition excellent in moldability, heat resistance, weather resistance, oil resistance, chemical resistance, adhesion, flexibility, wear resistance, strain recovery, and storage stability. The present invention also relates to a composition suitable for powder slush molding and a powder slush molded article using the composition.

  It is known that an acrylic block copolymer having methyl methacrylate as a hard segment and butyl acrylate as a soft segment has characteristics as a thermoplastic elastomer. By appropriately selecting the components constituting the block body, it is possible to give an extremely flexible elastomer as compared with other thermoplastic elastomers such as a styrene block body.

  In addition, the acrylic block copolymer has a feature that it is excellent in weather resistance, heat resistance, durability, oil resistance, and abrasion resistance. Further, in Patent Document 1, it is manufactured by an iniferter method. It is described that an acrylic block copolymer having a methacrylic block and an acrylic block exhibits excellent mechanical properties (such as tensile strength and elongation).

  There are various skin materials and interior materials as applications utilizing the characteristics of such an acrylic block copolymer. In addition, there are materials for members that directly touch human hands by making use of tactile sensation.

  Physical properties necessary for these skin materials include mechanical properties (such as tensile strength and elongation), scratch resistance, heat resistance, and strain recovery properties, as well as resistance to drugs that can be contacted. Furthermore, when the skin and the base material are directly bonded, the adhesion between the skin and the base material, and when the buffer material is provided between the skin and the base material, the adhesion between the skin and the base material is mentioned. It is done.

  As a method for molding the skin material, there is a powder slush molding method which is a powder molding method using a soft powder material. This method is widely used for molding the skin of automobile interior parts such as instrument panels, console boxes and door rims. This is because, according to the powder slush molding method, a product with a soft feel can be obtained, and leather textures and stitches can be provided on the product, the degree of design freedom is great, and the design is good. Unlike other molding methods such as injection molding and compression molding, this molding method does not apply shaping pressure during molding. For this reason, it is necessary to uniformly adhere the powder material to a complex-shaped mold during molding, and the powder is required to have excellent fluidity. At the same time, when the powder adhering to the mold melts, it must flow even under no pressure to form a film. For this reason, a low melt viscosity is also required.

  However, it has been difficult for conventional acrylic block copolymers to achieve both melt fluidity and heat resistance.

Japanese Unexamined Patent Publication No. 1-26619

  The purpose of the present invention is to improve the melt fluidity during molding while maintaining the weather resistance, oil resistance, chemical resistance, adhesion, flexibility and wear resistance that are the characteristics of acrylic block copolymers. And obtaining an acrylic block copolymer composition excellent in heat resistance.

  As a result of intensive studies in order to solve the above problems, the present inventors have found that the above problems can be effectively solved by increasing the molecular weight or crosslinking of the acrylic block copolymer at the time of molding. It came to solve.

  That is, the present invention comprises an acrylic block copolymer (A) consisting of a methacrylic polymer block (a) and an acrylic polymer block (b) and having an average of one or more hydroxyl groups per molecule and one molecule. The present invention relates to a thermoplastic elastomer composition comprising an acrylic polymer (B) having an average of 1.1 or more epoxy groups per unit.

  The thermoplastic elastomer composition according to the present invention is not only excellent in weather resistance, oil resistance, chemical resistance, adhesion, flexibility and abrasion resistance, but also excellent in moldability, heat resistance and strain recovery. ing. For this reason, the composition of this invention can be used conveniently for powder slush molding. Moreover, since the thermoplastic elastomer composition according to the present invention is excellent in storage stability, it is possible to provide a molded article having a stable quality.

  The thermoplastic elastomer composition according to the present invention contains an acrylic block copolymer (A) and an acrylic polymer (B). The acrylic block copolymer (A) comprises a methacrylic polymer block (a) mainly composed of a methacrylic polymer and an acrylic polymer block (b) mainly composed of an acrylic polymer, It has an average of 1 or more hydroxyl groups per molecule. The acrylic polymer (B) has an average of 1.1 or more epoxy groups per molecule. In the present composition, the hydroxyl group of the acrylic block copolymer (A) and the epoxy group of the acrylic polymer (B) usually react and crosslink by heating during molding. As a result, the heat resistance of the molded body is improved.

  Hereinafter, each component of the present invention will be described in detail.

<Acrylic block copolymer (A)>
The structure of the acrylic block copolymer (A) of the present invention is not particularly limited, and may be a linear block copolymer, a branched (star) block copolymer, or a mixture thereof. The structure of such a block copolymer may be appropriately selected according to the required physical properties of the acrylic block copolymer (A). However, from the viewpoint of cost and ease of polymerization, the linear block copolymer is selected. Polymers are preferred. The linear block copolymer may have any structure (arrangement). From the viewpoint of the physical properties of the linear block copolymer or the physical properties of the composition, the methacrylic polymer block (a ) Is expressed as a, and the acrylic polymer block (b) is expressed as b, (ab) _n type, b- (ab) _n type and (ab) _n -a type (n is 1) It is preferably at least one acrylic block copolymer selected from the group consisting of the above integers (for example, an integer of 1 to 3). Among these, an ab type diblock copolymer, an abb type triblock copolymer, or a mixture thereof is preferable from the viewpoint of easy handling during processing and physical properties of the composition.

  One or more hydroxyl groups are introduced per molecule into one or both of the methacrylic polymer block (a) and the acrylic polymer block (b). When the number is two or more, the mode in which the monomer (c) having a hydroxyl group is polymerized can be random copolymerization or block copolymerization. For example, an aba type triblock copolymer is represented by (a / z) -ba type, (a / z) -b- (a / z) type, zab- a-type, za-b-a-z type, a- (b / z) -a-type, a-b-za-type, a-z-b-za-type, (a / z) Any of a-(b / z)-(a / z) type, a za-z-b-z-a-z type, etc. may be sufficient. Here, z represents a monomer unit (c) having a hydroxyl group or a polymer block obtained by polymerizing a monomer unit (c) having a hydroxyl group, and (a / z) represents a methacrylic group. The monomer unit (c) is copolymerized with the polymer block (a), and (b / z) is a monomer unit (c) having a hydroxyl group in the acrylic polymer block (b). ) Is copolymerized.

  Moreover, the site | part in which z is contained in the methacrylic polymer block (a) or the acrylic polymer block (b) and the manner in which they are contained can be appropriately set according to the purpose.

  The molecular weight of the acrylic block copolymer (A) is not particularly limited, and may be determined from the molecular weights required for the methacrylic polymer block (a) and the acrylic polymer block (b). However, if the molecular weight is small, sufficient mechanical properties as an elastomer may not be exhibited. Conversely, if the molecular weight is larger than necessary, the processing properties may deteriorate. In the case of powder slush molding, since it is necessary to flow even under no pressure, if the molecular weight is large, the melt viscosity increases and the moldability may deteriorate. From such a viewpoint, the molecular weight of the acrylic block copolymer (A) is preferably 30,000 to 200,000 in terms of number average molecular weight, more preferably 35,000 to 150,000, still more preferably 40,000. ~ 100,000.

  The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography of the acrylic block copolymer (A) is not particularly limited, but is 1.8 or less. It is preferable that it is 1.5 or less. If Mw / Mn exceeds 1.8, the uniformity of the acrylic block copolymer may deteriorate.

  The composition ratio of the methacrylic polymer block (a) and the acrylic polymer block (b) constituting the acrylic block copolymer (A) is 5 to 90% by weight of the methacrylic polymer block (a). The acrylic polymer block (b) is preferably 95 to 10% by weight. From the viewpoint of maintaining the shape during molding and elasticity as an elastomer, the methacrylic polymer block (a) is more preferably 10 to 60% by weight, and the acrylic polymer block (b) is more preferably 90 to 40% by weight. Preferably, the methacrylic polymer block (a) is 15 to 50% by weight, and the acrylic polymer block (b) is 85 to 50% by weight. When the proportion of the methacrylic polymer block (a) is less than 5% by weight, the shape tends to be difficult to be maintained during molding. When the proportion of the acrylic polymer block (b) is less than 10% by weight, There is a tendency that the elasticity and the meltability at the time of molding are lowered.

  From the viewpoint of the hardness of the elastomer composition, when the proportion of the methacrylic polymer block (a) is small, the hardness is low, and when the proportion of the acrylic polymer block (b) is small, the hardness tends to be high. Yes, the composition is appropriately set according to the required hardness of the elastomer composition. Further, from the viewpoint of processing, when the proportion of (a) is small, the viscosity tends to be low, and when the proportion of (b) is small, the viscosity tends to be high, and the composition is appropriately set according to the required processing characteristics. .

The relationship between the glass transition temperature of the methacrylic polymer block (a) and the acrylic polymer block (b) constituting the acrylic block copolymer (A) is that it gives elastomer properties and rubber elasticity. It is preferable that the glass transition temperature of one of the polymer blocks is higher than the glass transition temperature of the other polymer block, and the glass transition temperature of each block (methacrylic polymer block ( It is more preferable that the glass transition temperature of a) is Tg _a and the glass transition temperature of the acrylic polymer block (b) is Tg _b ) satisfying the following relationship.
Tg _a > Tg _b
The glass transition temperature (Tg) of the polymer (the methacrylic polymer block (a) and the acrylic polymer block (b)) is set according to the following Fox formula. This can be done by setting.
_{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 portion, and Tg ₁ , Tg ₂ ,..., Tg _m represent the glass transition temperature of each polymerization monomer. W ₁ , W ₂ ,..., W _m represent the weight ratio of each polymerization monomer.

  As the glass transition temperature of each polymerization monomer in the Fox formula, for example, a value described in Polymer Handbook Third Edition (Wiley-Interscience 1989) may be used.

  The glass transition temperature can be measured by DSC (differential scanning calorimetry) or tan δ peak of dynamic viscoelasticity, but the polarities of the methacrylic polymer block (a) and the acrylic polymer block (b). If they are too close, or if the number of monomer chains in the block is too small, the measured values may deviate from the calculation formula based on the Fox equation.

<Methacrylic polymer block (a)>
The methacrylic polymer block (a) is a block obtained by polymerizing a monomer having a methacrylic acid ester as a main component, and is 50 to 100% by weight of the methacrylic acid ester and a vinyl type copolymerizable therewith. It is preferably composed of 0 to 50% by weight of monomer. Moreover, the monomer (c) which has a hydroxyl group may be included as methacrylic ester. When the proportion of the methacrylic acid ester is less than 50% by weight, the weather resistance, which is a characteristic of the methacrylic acid ester, may be impaired. As the methacrylic acid ester constituting the methacrylic polymer block (a) For example, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-pentyl methacrylate, n-hexyl methacrylate, methacrylic acid Methacrylic acid aliphatic hydrocarbons such as n-heptyl, n-octyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, decyl methacrylate, dodecyl methacrylate, stearyl methacrylate (for example, carbon number) 1-18 alkyl) esters; methacrylates Methacrylic acid alicyclic hydrocarbon esters such as cyclohexyl and methacrylic acid isobornyl; methacrylic acid aralkyl esters such as benzyl methacrylate; methacrylic acid aromatic hydrocarbon esters such as phenyl methacrylate and toluyl methacrylate; Esters of methacrylic acid such as 2-methoxyethyl methacrylate and 3-methoxybutyl methacrylate and functional group-containing alcohols having etheric oxygen; trifluoromethyl methacrylate, trifluoromethyl methyl methacrylate, meta 2-trifluoromethylethyl acrylate, 2-trifluoroethyl methacrylate, 2-perfluoroethylethyl methacrylate, 2-perfluoroethyl-2-perfluorobutylethyl methacrylate, 2-methacrylic acid 2- -Fluoroethyl, perfluoromethyl methacrylate, diperfluoromethyl methyl methacrylate, 2-perfluoromethyl-2-perfluoroethyl methyl methacrylate, 2-perfluorohexyl ethyl methacrylate, 2-permethacrylate Examples thereof include fluorinated alkyl methacrylates such as fluorodecylethyl and 2-perfluorohexadecylethyl methacrylate. These can be used alone or in combination of two or more. Among these, methyl methacrylate is preferable in terms of processability, cost, and availability.

  Examples of vinyl monomers copolymerizable with the methacrylic acid ester constituting the methacrylic polymer block (a) include, for example, acrylic acid esters, aromatic alkenyl compounds, vinyl cyanide compounds, conjugated diene compounds, Examples thereof include halogen-containing unsaturated compounds, vinyl ester compounds, maleimide compounds, and the like.

  Examples of the acrylate ester include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate, N-octyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, dodecyl acrylate, stearyl acrylate, and the like, acrylate aliphatic hydrocarbon (eg, alkyl having 1 to 18 carbon atoms) ester; cyclohexyl acrylate Acrylic acid cycloaliphatic hydrocarbon esters such as isobornyl acrylate; Acrylic aromatic hydrocarbon esters such as phenyl acrylate and toluyl acrylate; Aralkyl acrylates such as benzyl acrylate; 2-methoxyethyl acrylate , An ester of acrylic acid such as 3-methoxybutyl acrylate and a functional group-containing alcohol having etheric oxygen; trifluoromethyl methyl acrylate, 2-trifluoromethyl ethyl acrylate, 2-perfluoroethyl ethyl acrylate, 2-perfluoroethyl-2-perfluorobutylethyl acrylate, 2-perfluoroethyl acrylate, perfluoromethyl acrylate, diperfluoromethylmethyl acrylate, 2-perfluoromethyl-2-perfluoroethyl acrylate Examples thereof include fluorinated alkyl acrylates such as methyl, 2-perfluorohexylethyl acrylate, 2-perfluorodecylethyl acrylate, and 2-perfluorohexadecylethyl acrylate.

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

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

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

  These compounds can be used alone or in combination of two or more. These vinyl monomers are preferably selected from the viewpoints of adjusting the glass transition temperature required for the methacrylic polymer block (a) and compatibility with the acrylic block (b).

In particular, in the case of powder slush molding should be flowing at no pressure, the cohesive force and glass transition temperature Tg _a of the methacrylic polymer block (a) is increased, the higher the melt viscosity, the moldability It tends to get worse. For this reason, the glass transition temperature of the methacrylic polymer block (a) is preferably from 25 to 130 ° C, more preferably from 50 to 130 ° C, from the viewpoints of thermal deformability and moldability of the elastomer composition. Preferably it is 70-100 degreeC. From this point, it is desirable that the methacrylic polymer block (a) is mainly composed of methyl methacrylate, the increase in the glass transition temperature due to the introduction of an acid anhydride group or a carboxyl group, and the methacrylic polymer. For the purpose of adjusting the glass transition temperature of the block (a), polymerizing at least one monomer selected from the group consisting of ethyl acrylate, acrylic acid-n-butyl and acrylic acid-2-methoxyethyl. preferable. Of these, ethyl acrylate is particularly preferable from the viewpoint of compatibility with methyl methacrylate.

Tg _a configuration of the methacrylic polymer block (a) in accordance with said Fox equation, can be performed by setting the weight ratio of the monomers of each polymer portion.

<Acrylic polymer block (b)>
The acrylic polymer block (b) is a block obtained by polymerizing a monomer having an acrylic ester as a main component, and includes 50 to 100% by weight of the acrylic ester and a vinyl monomer copolymerizable therewith. It is preferably composed of 0 to 50% by weight. If the proportion of the acrylic ester is less than 50% by weight, the physical properties of the composition, particularly flexibility and oil resistance, which are characteristic when the acrylic ester is used, may be impaired. The acrylic polymer block (b) may contain a monomer having a hydroxyl group as an acrylate ester.

  Examples of the acrylate ester constituting the acrylic polymer block (b) include the same monomers as the acrylate ester exemplified as the monomer constituting the methacrylic polymer block (a). it can.

  These can be used alone or in combination of two or more thereof. Among these, acrylic acid-n-butyl is preferable from the viewpoint of rubber elasticity, low temperature characteristics and cost balance. If oil resistance and mechanical properties are required, ethyl acrylate is preferred. In addition, when it is necessary to impart low temperature characteristics and oil resistance and to improve the surface tackiness of the resin, 2-methoxyethyl acrylate is preferred. Further, when a balance between oil resistance and low-temperature characteristics is required, it is preferable to use a combination of ethyl acrylate, acrylic acid-n-butyl and acrylic acid-2-methoxyethyl.

  The acrylic polymer block (b) is at least one monomer selected from the group consisting of acrylate-n-butyl, ethyl acrylate, and 2-methoxyethyl acrylate in terms of cost and physical property balance. More preferably, it consists of 50 to 100% by weight and 50 to 0% by weight of other acrylic ester and / or other vinyl monomer copolymerizable therewith.

  Examples of vinyl monomers copolymerizable with the acrylic ester constituting the acrylic polymer block (b) include methacrylic ester, aromatic alkenyl compound, vinyl cyanide compound, conjugated diene compound, halogen, and the like. -Containing unsaturated compounds, silicon-containing unsaturated compounds, unsaturated carboxylic acid compounds, unsaturated dicarboxylic acid compounds, vinyl ester compounds, maleimide compounds, etc., and specific examples thereof include methacrylic polymer blocks The thing similar to the said thing used for (a) can be mention | raise | lifted.

  These vinyl monomers can be used alone or in combination of two or more. These vinyl monomers are appropriately selected in consideration of the balance of the glass transition temperature and oil resistance required for the acrylic polymer block (b), compatibility with the methacrylic polymer block (a), and the like. Choose the preferred one. For example, acrylonitrile may be copolymerized for the purpose of improving the oil resistance of the composition.

  From the viewpoint of rubber elasticity of the elastomer composition, the glass transition temperature of the acrylic polymer block (b) is preferably 25 ° C. or less, more preferably 0 ° C. or less, and further preferably −20 ° C. or less. When the glass transition temperature of the acrylic polymer block (b) is higher than the temperature of the environment in which the elastomer composition is used, flexibility and rubber elasticity are hardly exhibited.

The Tg _b of the acrylic polymer block (b) can be set by setting the weight ratio of the monomers in each polymer portion according to the Fox formula.

<Hydroxyl group>
The hydroxyl group easily reacts with the epoxy group of the acrylic polymer (B). The hydroxyl group may be introduced into the main chain of the acrylic block copolymer (A) or may be introduced into the side chain, but from the ease of introduction into the acrylic block copolymer (A). It is preferably introduced into the side chain. Furthermore, in terms of easy introduction, the general formula (1):

（式中、Ｒ¹は水素またはメチル基で、互いに同一でも異なっていてもよい。Ｒ²は炭素数１〜２０のアルキル基、炭素数６〜２０のシクロアルキル基またはアリール基、炭素数７〜２０のアラルキル基、または、−（Ｏ（ＣＨ₂）_n）_p−（Ｏ（ＣＨ₂）_m）_q−であってｎおよびｍが２〜４、ｐが１〜２０、ｑが０〜２０の整数、ｎ、ｍ、ｐ、ｑは互いに同一であっても異なっていても良い）で表される単量体単位（ｃ）として、本発明に係る熱可塑性エラストマー組成物から得られる成形体に耐薬品性やゴム弾性を付与しつつ、高温での機械特性を保持させるために、メタアクリル系重合体ブロック（ａ）および／またはアクリル系重合体ブロック（ｂ）に、一分子当たり１つ以上導入する。

(In the formula, R ¹ is hydrogen or a methyl group and may be the same or different. R ² is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms or an aryl group, and 7 carbon atoms. 20 aralkyl group, _{or, - (O (CH 2)} n) p - (O (CH 2) m) q - in an in n and m is 2 to 4, p is 1 to 20, q is 0 The integer obtained from the thermoplastic elastomer composition according to the present invention as a monomer unit (c) represented by an integer of 20, n, m, p and q may be the same or different. 1 molecule per molecule is added to the methacrylic polymer block (a) and / or the acrylic polymer block (b) in order to retain the mechanical properties at high temperatures while imparting chemical resistance and rubber elasticity to the body. Introduce more than one.

  In the present invention, the hydroxyl group only needs to act as a reaction point with the acrylic polymer (B), and preferably acts as a reaction point or a crosslinking point for the block copolymer to have a high molecular weight or to be crosslinked.

  The number of hydroxyl groups is the reactivity with the acrylic polymer (B), the structure and composition of the acrylic block copolymer (A), the number of blocks constituting the acrylic block copolymer (A), and the glass transition. Varies with temperature. The number needs to be appropriately set according to need, but is 1.0 or more, preferably 2.0 or more per molecule of the block copolymer. This is because when the number is less than 1.0, improvement in heat resistance due to increase in the molecular weight or crosslinking of the block copolymer may be insufficient.

  The method for introducing the hydroxyl group into the block copolymer (A) is not particularly limited, but a (meth) acrylic monomer containing a hydroxyl group may be directly polymerized during the polymerization of the block copolymer (A). After the polymer (A) is polymerized, the diol component may be introduced using an esterification reaction or a transesterification reaction. From the viewpoint of easy reaction, it is preferable to directly polymerize a (meth) acrylic monomer containing a hydroxyl group at the time of polymerization of the block copolymer (A). Here, in this application, (meth) acryl means acryl or methacryl.

  Specific (meth) acrylic monomers include (meth) acrylic acid-2-hydroxyethyl, (meth) acrylic acid-2-hydroxypropyl, (meth) acrylic acid-3-hydroxypropyl, (meth) acrylic acid- 4-hydroxybutyl, Blemmer E series (Nippon Yushi Co., Ltd.), Blemmer PE series (Nippon Yushi Co., Ltd.), Blemmer AE series (Nippon Yushi Co., Ltd.), Blemmer P (Nippon Yushi Co., Ltd.), Blemmer PP Series (Nippon Yushi Co., Ltd.), Blemmer AP Series (Nippon Yushi Co., Ltd.), Blemmer PEP Series (Nippon Yushi Co., Ltd.), Blemmer AEP Series (Nippon Yushi Co., Ltd.), Blemmer PET Series (Nippon Yushi Co., Ltd.) )), Blemmer AET series (Nippon Yushi Co., Ltd.), Blemmer PPT series (Nippon Yushi ( )), Such as Blenmer APT series (NOF Corporation) are exemplified.

  These compounds can be used alone or in combination of two or more. Among these, (meth) acrylic acid-2-hydroxyethyl, (meth) acrylic acid-2-hydroxypropyl, and (meth) acrylic acid-4-hydroxybutyl are easy to polymerize and are easy to obtain. preferable. Furthermore, from the viewpoint of suppressing deterioration of moldability due to reaction of hydroxyl groups and epoxy groups during long-term storage of the obtained thermoplastic elastomer composition (maintaining long-term storage stability), (meth) acrylic Acid-2-hydroxyethyl is more preferred.

Although not particularly limited, when it is contained in the methacrylic polymer block (a), R ^{1 in the} general formula (1) is preferably a methyl group, and when it is contained in the acrylic polymer block (b), R ^{1 in the} general formula (1) is preferably hydrogen. When R ¹ is hydrogen when included in the methacrylic polymer block (a), or when R ¹ is a methyl group when included in the acrylic polymer block (b), the acrylic block copolymer The polymerization operation of (A) becomes complicated, the difference in glass transition temperature between the methacrylic polymer block (a) and the acrylic polymer block (b) becomes small, and the acrylic block copolymer (A) Rubber elasticity tends to decrease.

<Method for producing acrylic block copolymer (A)>
The method for producing the acrylic block copolymer (A) is not particularly limited, but it is preferable to use controlled polymerization using an initiator. Examples of controlled polymerization include living anion polymerization, radical polymerization using a chain transfer agent, and recently developed living radical polymerization. Of these, living radical polymerization is preferred from the viewpoint of controlling the molecular weight and structure of the acrylic block copolymer.

  Living radical polymerization is radical polymerization in which the activity at the polymerization terminal is maintained without loss. In the narrow sense, living polymerization refers to polymerization in which the terminal always has activity, but generally includes pseudo-living polymerization in which the terminal is inactivated and the terminal is in equilibrium. . The definition here is also the latter. Living radical polymerization has been actively researched by various groups in recent years.

  Examples thereof include those using a chain transfer agent such as polysulfide, cobalt porphyrin complex (J. Am. Chem. Soc., 1994, 116, 7943), Atom transfer radical polymerization using radical scavengers such as nitroxide compounds (Macromolecules, 1994, Vol. 27, 7228), organic halides as initiators and transition metal complexes as catalysts ( Atom Transfer Radical Polymerization (ATRP). In the present invention, there is no particular restriction as to which of these methods is used, but atom transfer radical polymerization is preferred from the viewpoint of ease of control.

  Specific examples of the atom transfer radical polymerization include the method described in JP-A-2004-107447.

<Acrylic polymer (B)>
The acrylic polymer (B) constituting the thermoplastic elastomer composition according to the present invention is a polymer containing an average of 1.1 or more epoxy groups per molecule. The acrylic polymer (B) improves the molding fluidity as a plasticizer during molding of the composition, and at the same time reacts with the hydroxyl groups in the acrylic block copolymer (A) during molding, and the acrylic block copolymer. (A) can be made high molecular weight or crosslinked.

  The average number of epoxy groups per acrylic polymer (B) molecule is 1.1 or more, preferably 1.5 or more, more preferably 2.0 or more. The number varies depending on the reactivity of the epoxy group, the site and mode in which the epoxy group is contained, and the number, site and mode of hydroxyl groups per molecule of the acrylic block copolymer (A). When the epoxy group content is less than 1.1, the block copolymer tends to have a high molecular weight or insufficient crosslinking, and the heat resistance of the acrylic block copolymer (A) tends to be insufficient. is there.

  The acrylic polymer (B) is obtained by polymerizing one or two or more (meth) acrylic monomers, or one or two or more (meth) acrylic monomers and (meth). It is preferably obtained by polymerizing other monomers other than acrylic monomers.

  Examples of (meth) acrylic monomers include acryloyl group-containing monomers and methacryloyl group-containing monomers. Specific examples include methyl (meth) acrylate, ethyl (meth) acrylate, (meth) Propyl acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylic acid, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, ( Examples include glycidyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate, phenoxyethyl acrylate, and the like. Moreover, as a monomer other than the (meth) acrylic monomer, a monomer copolymerizable with the acrylic monomer, such as vinyl acetate or styrene, can be used.

  Here, in terms of weather resistance, compatibility with the acrylic block copolymer (A), and discoloration of the molded product, an acryloyl group-containing single amount with respect to all monomer units in the acrylic polymer (B). The body unit ratio is preferably 70% by mass or more.

  In addition, from the viewpoint of compatibility with the acrylic block copolymer (A), at least one single member selected from the group consisting of acrylic acid-n-butyl, ethyl acrylate, and 2-methoxyethyl acrylate is used. Those consisting of 50 to 100% by weight of a monomer and 50 to 0% by weight of other acrylic acid ester and / or other vinyl monomer copolymerizable therewith are preferred. As the vinyl monomer, styrene is preferable.

  The weight average molecular weight of the acrylic polymer (B) is not particularly limited, but for molded products, those having a low molecular weight of 30,000 or less are preferable, those having 500 to 30,000 are more preferable, and 500 to 10,000 is particularly preferred. When the weight average molecular weight is less than 500, the molded product tends to be sticky. On the other hand, when the weight average molecular weight exceeds 30,000, plasticization of the molded product becomes insufficient.

  The viscosity of the acrylic polymer (B) is preferably 35,000 mPa · s or less when measured with a cone-plate type rotational viscometer (E-type viscometer) at 25 ° C. A more preferable viscosity is 10,000 mPa · s or less. A particularly preferred viscosity is 5,000 mPa · s or less. When the viscosity is higher than 35,000 mPa · s, the plasticizing effect of the composition tends to decrease. There is no particular lower limit of the preferred viscosity, but the normal viscosity of the acrylic polymer is preferably 10 mPa · s or more.

  The glass transition temperature Tg of the acrylic polymer (B) measured by differential scanning calorimetry (DSC) is preferably 100 ° C. or lower, more preferably 25 ° C. or lower, and further preferably 0 ° C. or lower. Yes, particularly preferably -30 ° C or lower. When glass transition temperature Tg exceeds 100 degreeC, there exists a tendency for the effect which improves a moldability as a plasticizer to become inadequate, and it exists in the tendency for the softness | flexibility of the molded object obtained to fall.

  The acrylic polymer (B) is produced by polymerizing by a known predetermined method. The polymerization method may be appropriately selected as necessary. For example, suspension polymerization, emulsion polymerization, bulk polymerization, living anion polymerization, polymerization using a chain transfer agent, and controlled polymerization such as living radical polymerization may be performed. However, controlled polymerization is preferred in which a polymer having good weather resistance and heat resistance and a relatively low molecular weight and a small molecular weight distribution can be obtained. Specifically, JP-A-57-502171 and JP-A-59-6207 are preferred. The methods using high-temperature continuous polymerization disclosed in JP-A-60-215007 and WO01 / 083619 are more preferable in terms of cost.

  Since an acrylic polymer having a relatively low molecular weight can be obtained without using a polymerization initiator or a chain transfer agent, the acrylic polymer (B) should be obtained by a polymerization reaction at a temperature of 180 to 350 ° C. Is preferred. The acrylic polymer thus obtained is excellent as a plasticizer and has good weather resistance.

  Specific examples of the acrylic polymer (B) include ARUFON (registered trademark) XG4000, ARUFON UG4000, ARUFON XG4010, ARUFON UG4010, ARUFON XD945, ARUFON XD950, ARUFON UG4030, ARUFON UG40ON, and ARUONON 40, URU70ON from Toagosei Co., Ltd. Can be used for These are acrylic polymers such as all acrylic and acrylate / styrene, and contain 1.1 or more epoxy groups in one molecule.

  The acrylic polymer (B) is preferably used in the range of 0.5 to 50 parts by weight and used in the range of 1 to 30 parts by weight with respect to 100 parts by weight of the acrylic block copolymer (A). It is more preferable to use in the range of 1.5 to 20 parts by weight. If the blending amount is less than 0.5 parts by weight, the moldability and the heat resistance of the resulting molded product may not be sufficient, and if it exceeds 50 parts by weight, the mechanical properties of the resulting composition tend to deteriorate. .

<Thermoplastic elastomer composition>
While the thermoplastic elastomer composition of the present invention has low melt viscosity and excellent moldability, the hydroxyl group in the acrylic block copolymer (A) reacts with the epoxy group in the acrylic polymer (B) during molding. Thus, the acrylic block copolymer (A) is preferably increased in molecular weight or crosslinked.

  If necessary, a curing accelerator may be added to the thermoplastic elastomer composition of the present invention in order to promote the reaction between the hydroxyl group and the epoxy group during molding. Examples of curing accelerators include various acidic compounds and basic compounds, but suppresses deterioration of moldability due to the reaction of hydroxyl groups and epoxy groups during long-term storage (maintains long-term storage stability). From the viewpoint, it is preferable to add a thermal latent acid catalyst that shows activity when heated at a predetermined temperature.

  The thermal latent acid catalyst is preferably a compound that exhibits acid catalytic activity at a temperature of 60 ° C. or higher. When this heat-latent acid catalyst exhibits acid catalyst activity at a temperature lower than 60 ° C., the resulting composition may deteriorate in formability during storage.

  Specifically, the heat latent acid catalyst includes (i) a compound obtained by neutralizing a proton acid with an Arrhenius base, (ii) a compound obtained by neutralizing a proton acid with a Lewis base, and (iii) a Lewis acid obtained with a Lewis base. Neutralized compounds, (iv) mixtures of Lewis acids and trialkyl phosphates, (v) sulfonate esters, (vi) phosphate esters, (vii) onium compounds, (viii) compounds derived from aluminum complexes And (ix) quaternary onium salts are preferred.

  Examples of the compound (i) obtained by neutralizing a protic acid with an Arrhenius base include, for example, carboxylic acids, halogenocarboxylic acids, sulfonic acids, sulfuric acid monoesters, phosphoric acid mono and diesters, polyphosphoric acid esters, boric acid mono and diesters. , Etc. are neutralized with various metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, zinc hydroxide and iron hydroxide.

  Examples of the compound (ii) obtained by neutralizing a protonic acid with a Lewis base include halogenocarboxylic acids, sulfonic acids, sulfuric acid monoesters, phosphoric acid mono and diesters, polyphosphoric acid esters, boric acid mono and diesters, and the like. Various amines such as ammonia, monoethylamine, triethylamine, pyridine, piperidine, aniline, morpholine, cyclohexylamine, n-butylamine, monoethynolamine, diethanolamine, triethanolamine, or trialkylphosphine, triarylphosphine, trialkylphosphine Phyte, compounds neutralized with triaryl phosphite, and Necurer 2500X, X47-110, 3525, 5225 (trade name, king-in) commercially available as acid-base blocking catalysts Stories Co., Ltd.) and the like.

Examples of the compound (iii) obtained by neutralizing a Lewis acid with a Lewis base include compounds obtained by neutralizing a Lewis acid such as BF ₃ , FeCl ₃ , SnCl ₄ , AlCl ₃ , ZnCl ₂ with the above Lewis base. . Or the mixture (iv) of the said Lewis' acid and a trialkyl phosphate is also mentioned.

  Examples of the sulfonate esters (v) include those represented by the formula (2)

（ただし、式中のＲ³はフェニル基、置換フェニル基、ナフチル基、置換ナフチル基またはアルキル基、Ｒ⁴は一級炭素または二級炭素を介してスルホニルオキシ基と結合している炭素数３〜１８のアルキル基、アルケニル基、アリール基、アルカリール基、アルカノール基、飽和のシクロアルキル基またはヒドロキシシクロアルキル基もしくは不飽和のシクロアルケニルまたはヒドロキシシクロアルケニル基である。）で表される化合物が挙げられる。このような化合物としては、具体的には、例えば、メタンスルホン酸、エタンスルホン酸、ベンゼンスルホン酸、ドデシルベンゼンスルホン酸、ナフタレンスルホン酸、ノニルナフタレンスルホン酸などのスルホン酸類とｎ−プロパノール、ｎ−ブタノール、ｎ−ヘキサノール、ｎ−オクタノールなどの第一級アルコール類またはイソプロパノール、２−ブタノール、２−ヘキサノール、２−オクタノール、シクロヘキサノールなどの第二級アルコール類とのエステル化物、さらには前記スルホン酸類とオキシラン基含有化合物との反応により得られるβ−ヒドロキシアルキルスルホン酸エステル類などが挙げられる。

(In the formula, R ³ is a phenyl group, a substituted phenyl group, a naphthyl group, a substituted naphthyl group or an alkyl group, and R ⁴ is a carbon number of 3 to 3 bonded to the sulfonyloxy group via a primary carbon or a secondary carbon. 18 alkyl groups, alkenyl groups, aryl groups, alkaryl groups, alkanol groups, saturated cycloalkyl groups, hydroxycycloalkyl groups, unsaturated cycloalkenyl groups, or hydroxycycloalkenyl groups. It is done. Specific examples of such compounds include sulfonic acids such as methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid, naphthalenesulfonic acid, and nonylnaphthalenesulfonic acid, and n-propanol, n- Primary alcohols such as butanol, n-hexanol and n-octanol or esterified products with secondary alcohols such as isopropanol, 2-butanol, 2-hexanol, 2-octanol and cyclohexanol, and the sulfonic acids And β-hydroxyalkyl sulfonic acid esters obtained by the reaction of oxirane group-containing compounds.

  Examples of the phosphate esters (vi) include compounds represented by the formula (3).

（式中のＲ⁵は炭素数３〜１０のアルキル基、シクロアルキル基またはアリール基、ｈは１または２である。）
より具体的には、ｎ−プロパノール、ｎ−ブタノール、ｎ−ヘキサノール、ｎ−オクタノール、２−エチルヘキサノール等の第一級アルコール類、およびイソプロパノール、２−ブタノール、２−ヘキサノール、２−オクタノール、シクロヘキサノール等の第二級アルコール類のリン酸モノエステル類あるいはリン酸ジエステル類が挙げられる。

(In the formula, R ⁵ is an alkyl group having 3 to 10 carbon atoms, a cycloalkyl group or an aryl group, and h is 1 or 2.)
More specifically, primary alcohols such as n-propanol, n-butanol, n-hexanol, n-octanol, 2-ethylhexanol, and isopropanol, 2-butanol, 2-hexanol, 2-octanol, cyclo Examples thereof include phosphoric acid monoesters or phosphoric acid diesters of secondary alcohols such as hexanol.

Examples of the onium compound (vii) include compounds represented by formulas (4) to (7).
[(R ⁶ ) ₃ NR ⁷ ] + · X ⁻ (4)
[(R ⁸ ) ₃ PR ⁹ ] + · X ⁻ (5)
[(R ¹⁰ ) ₂ OR ¹¹ ] + · X ⁻ (6)
[(R ¹² ) ₂ SR ¹³ ] + · X ⁻ (7)
R ⁶ , R ⁸ , R ¹⁰ and R ¹² in the formula are each an alkyl group, alkenyl group, aryl group, alkaryl group, alkanol group or cycloalkyl group having 1 to 12 carbon atoms, wherein two R ⁶ , R ⁸ , R ¹⁰ and R ¹² may be bonded to each other to form a heterocycle having N, P, O or S as a heteroatom, and R ⁷ , R ⁹ , R ¹¹ and R ¹³ are a hydrogen atom, An alkyl group having 1 to 12 carbon atoms, an alkenyl group, an aryl group, an alkaryl group, and X ⁻ are SbF ₆ ⁻ , AsF ₆ ⁻ , PF ₆ ⁻ or BF ₄ ⁻ .

  Moreover, the compound (viii) induced | guided | derived from an aluminum complex can be used as a catalyst. Specific examples include metal soaps such as aluminum octylate, β-diketonate aluminum complexes, β-diketoesterate aluminum complexes, and o-carbonylphenolate aluminum complexes. Examples of the β-diketone used as the ligand of the aluminum complex include 1,3-diphenyl-1,3-propanedione, 1-phenyl-1,3-butanedione, 2,4-pentanedione, 3-phenyl- 2,4-pentanedione, 5-dimethyl-2,4-hexanedione, 5-phenyl-2,4-pentanedione, 2,6-dimethyl-3,5-heptanedione, 2,6-tetramethyl-3 , 5-pentanedione and the like.

  Examples of the β-diketoester include ethyl acetoacetate, propyl acetoacetate, butyl acetoacetate, t-butyl acetoacetate, and ethyl benzoyl acetate. Examples of o-carbonylphenol include 2-hydroxy-benzaldehyde, 2 ′ -Hydroxy-acetophenone, methyl-2-hydroxybenzoate, phenyl-2-hydroxybenzoate and the like.

  Furthermore, in order to increase the activity, an aluminum complex in which a silanol compound is further mixed with the above aluminum complex may be used. Such silanol compounds include triphenylsilanol, tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane. Ethoxysilane, diphenyldiethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane, trifluoropropyltrimethoxysilane, heptadecatrifluorodecyltrimethoxysilane, triphenylmethoxysilane, triphenylethoxysilane Etc.

  Furthermore, a quaternary onium salt (ix) can also be used as a catalyst. More specifically, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium halide such as tetrabutylammonium iodide, tetrabutylphosphonium chloride, tetrabutylphosphonium bromide, tetrabutylphosphonium halide such as tetrabutylphosphonium iodide, And tetraphenylphosphonium halides such as tetraphenylphosphonium chloride, tetraphenylphosphonium bromide, and tetraphenylphosphonium iodide.

  Among these catalysts, a compound obtained by neutralizing a proton acid with an Arrhenius base is preferable in terms of cost and availability, and is derived from an aluminum complex in terms of water resistance and coloring of the finally obtained molded article. Are preferred.

  In the thermoplastic elastomer composition of the present invention, these curing accelerators can be used alone or in combination of two or more. The blending amount is preferably in the range of 0.01 to 10 parts by weight with respect to 100 parts by weight of the acrylic block copolymer. If the amount of the heat latent acid catalyst is less than 0.01 parts by weight, the catalytic effect tends to be insufficient. If the amount exceeds 10 parts by weight, the finally obtained molded product is colored or the water resistance is lowered. There is a tendency.

  The thermoplastic elastomer composition of the present invention may further contain a filler as necessary. The filler is not particularly limited, but wood powder, pulp, cotton chips, asbestos, glass fiber, carbon fiber, mica, walnut shell powder, rice husk powder, graphite, diatomaceous earth, white clay, silica (fumed silica, sedimentation) Silica, crystalline silica, fused silica, dolomite, anhydrous silicic acid, hydrous silicic acid, etc.), reinforcing fillers such as carbon black; heavy calcium carbonate, colloidal calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, Fillers such as clay, talc, titanium oxide, bentonite, organic bentonite, ferric oxide, red pepper, fine aluminum powder, flint powder, zinc oxide, activated zinc white, zinc dust, zinc carbonate and shirasu balloon; asbestos, Glass fiber and glass filament, carbon fiber, Kevlar fiber, polyethylene fiber And fibrous fillers such as and the like.

  Among these fillers, inorganic fillers are more preferable from the viewpoint of improving mechanical properties, reinforcing effect, cost, and the like, and titanium oxide, carbon black, calcium carbonate, silica, and talc are more preferable.

  In the case of silica, silica whose surface has been previously hydrophobically treated with an organosilicon compound such as organosilane, organosilazane, or diorganopolysiloxane may be used. Furthermore, calcium carbonate is surface-treated using surface treatment agents such as organic substances such as fatty acids, fatty acid soaps and fatty acid esters, various surfactants, and various coupling agents such as silane coupling agents and titanate coupling agents. You may use what has been given.

  When a filler is used, the blending amount is preferably in the range of 5 to 200 parts by weight, and in the range of 10 to 100 parts by weight, with respect to 100 parts by weight of the acrylic block copolymer (A). Is more preferable. If the blending amount is less than 5 parts by weight, the reinforcing effect of the resulting molded product may not be sufficient, and if it exceeds 200 parts by weight, the molding of the resulting composition tends to be reduced. The fillers can be used alone or in combination of two or more.

  If necessary, the thermoplastic elastomer composition of the present invention may be blended with various lubricants for moldability, mold releasability from the mold, and low friction of the surface of the resulting molded article.

  Examples of lubricants include fatty acids such as stearic acid and palmitic acid, fatty acid metal salts such as calcium stearate, zinc stearate, magnesium stearate, potassium palmitate and sodium palmitate, polyethylene wax, polypropylene wax, and montanic acid wax. Waxes, low molecular weight polyolefins such as low molecular weight polyethylene and low molecular weight polypropylene, polyorganosiloxanes such as dimethylpolysiloxane, amide-based lubricants such as octadecylamine, alkyl phosphate, fatty acid ester, ethylenebisstearylamide, tetrafluoroethylene Fluorine resin powder such as resin, molybdenum disulfide powder, silicone resin powder, silicone rubber powder, silica and the like can be used. These can be used alone or in combination of two or more. Among these, stearic acid, zinc stearate, calcium stearate, fatty acid ester, and ethylene bisstearyl amide are preferable because of excellent cost and moldability.

  When using a lubricant, the blending amount is preferably in the range of 0.1 to 20 parts by weight, and in the range of 0.2 to 10 parts by weight with respect to 100 parts by weight of the acrylic block copolymer (A). Is more preferable. When the blending amount is less than 0.1 part by weight, the improvement effect of moldability and the reduction of friction of the resulting molded body may be insufficient. When the blending amount exceeds 20 parts by weight, the resulting molded body machine Characteristics and chemical resistance tend to deteriorate. The lubricants can be used alone or in combination of two or more.

  Various additives other than the above may be added to the thermoplastic elastomer composition of the present invention, if necessary, for the purpose of adjusting the physical properties of the thermoplastic elastomer composition and the molded article to be obtained. Examples of such additives include stabilizers, plasticizers, flexibility imparting agents, flame retardants, pigments, antistatic agents, and antibacterial and antifungal agents.

  Examples of the stabilizer include an antioxidant, a light stabilizer, and an ultraviolet absorber. Antiaging agents include, for example, phenyl-α-naphthylamine (PAN), octyldiphenylamine, N, N′-diphenyl-p-phenylenediamine (DPPD), N, N′-di-β-naphthyl-p-phenylenediamine (DNPD), N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine, N-phenyl-N′-isopropyl-p-phenylenediamine (IPPN), N, N′-diallyl-p -Phenylenediamine, phenothiazine derivatives, diallyl-p-phenylenediamine mixture, alkylated phenylenediamine, 4,4'-bis (α, α-dimethylbenzyl) diphenylamine, N-phenyl-N '-(3-methacryloyloxy- 2-hydropropyl) -p-phenylenediamine, diallylphenylenedia Amine-based antioxidants such as N- (1-methylheptyl) -N'-phenyl-p-phenylenediamine, diphenylamine derivatives, 2-mercaptobenzimidazole (MBI), etc. Phenol-based aging such as imidazole-based anti-aging agent, 2,6-di-t-butyl-4-methylphenol, pentaerythrityltetrakis [3- (5-di-t-butyl-4-hydroxyphenol) -propinate] Inhibitors, phosphate anti-aging agents such as nickel diethyl-dithiocarbamate, secondary anti-aging agents such as triphenyl phosphite, 2-t-butyl-6- (3-t-butyl-2-hydroxy-5 -Methylbenzyl) -4-methylphenyl acrylate, 2- [1- (2-hydroxy-3,5-di Such as t- pentylphenyl) ethyl] -4,6-di -t- pentylphenyl acrylate. 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-cyano-3,3′-diphenyl acrylate, 2-hydroxy-5-chlorobenzophenone, 2-hydroxy-4-methoxybenzophenone-2-hydroxy-4-octoxybenzophenone, monoglycol sari Examples include tyrates, oxalic acid amides, 2,2 ′, 4,4′-tetrahydroxybenzophenone, and the like.

  Specific examples of such stabilizers include Irganox (registered trademark) 1010 (manufactured by Ciba Specialty Chemicals Co., Ltd.), Sanol (registered trademark) LS770 (Sankyo Lifetech Co., Ltd.), Adekastab (registered trademark) LA -57 (Asahi Denka Kogyo Co., Ltd.), Adekastab LA-68 (Asahi Denka Kogyo Co., Ltd.), Chimassorb (registered trademark) 944 (Ciba Specialty Chemicals Co., Ltd.), Sanol LS765 (Sankyo Lifetech Co., Ltd.) Adeka Stub LA-62 (Asahi Denka Kogyo Co., Ltd.), TINUVIN (registered trademark) 144 (Ciba Specialty Chemicals Co., Ltd.), Adeka Stub LA-63 (Asahi Denka Kogyo Co., Ltd.), TINUVIN 622 (Ciba Specialty KK) Chemicals Co., Ltd.) Decastab LA-32 (Asahi Denka Kogyo Co., Ltd.), Adekastab LA-36 (Asahi Denka Kogyo Co., Ltd.), TINUVIN571 (Ciba Specialty Chemicals Co., Ltd.), TINUVIN234 (Ciba Specialty Chemicals Co., Ltd.), ADK STAB LA-31 (manufactured by Asahi Denka Kogyo Co., Ltd.), TINUVIN 1130 (manufactured by Ciba Specialty Chemicals Co., Ltd.), ADK STAB AO-20 (manufactured by Asahi Denka Kogyo Co., Ltd.), ADK STAB AO-50 (manufactured by Asahi Denka Kogyo Co., Ltd.) , ADK STAB 2112 (manufactured by Asahi Denka Kogyo Co., Ltd.), ADK STAB PEP-36, manufactured by Asahi Denka Kogyo Co., Ltd., Sumilyzer GM (Sumitomo Chemical Co., Ltd.), Sumilyzer GS (Sumitomo Chemical Industrial Co., Ltd.), Sumilyzer TP-D (Sumitomo) Chemical Industry Co., Ltd. And the like. These may be used alone or in combination of two or more. Among them, Sanol LS770, Irganox 1010, Sumilizer GS, and TINUVIN234 are preferable because they are an effect of preventing deterioration and cost due to heat and light of the acrylic block body.

  Examples of the plasticizer include dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate, di- (2-ethylhexyl) phthalate, diheptyl phthalate, diisodecyl phthalate, and di-n-octyl phthalate. Phthalic acid derivatives such as diisononyl phthalate, ditridecyl phthalate, octyl decyl phthalate, butyl benzyl phthalate, dicyclohexyl phthalate; isophthalic acid derivatives such as dimethyl isophthalate; and di- (2-ethylhexyl) tetrahydrophthalic acid Tetrahydrophthalic acid derivatives; adipic acid derivatives such as dimethyl adipate, dibutyl adipate, di-n-hexyl adipate, di- (2-ethylhexyl) adipate, isononyl adipate, diisodecyl adipate, dibutyl diglycol adipate ; Azelaic acid derivatives such as di-2-ethylhexyl xylate; sebacic acid derivatives such as dibutyl sebacate; dodecane-2-acid derivatives; maleic acid derivatives such as dibutyl maleate and di-2-ethylhexyl maleate; dibutyl fumarate etc. Fumaric acid derivatives; trimellitic acid derivatives such as tris-2-ethylhexyl trimellitic acid; pyromellitic acid derivatives; citric acid derivatives such as acetyltributyl citrate; itaconic acid derivatives; oleic acid derivatives; ricinoleic acid derivatives; stearic acid derivatives; Derivatives; sulfonic acid derivatives; phosphoric acid derivatives; glutaric acid derivatives; polyester plasticizers that are polymers of dibasic acids such as adipic acid, azelaic acid, and phthalic acid and glycols and monohydric alcohols, glycol derivatives, glycerin derivatives, Paraffin derivatives of fluorinated paraffin, epoxy derivatives polyester polymerization type plasticizers, polyether polymerization type plasticizers, ethylene carbonate, or the like carbonate derivatives such as propylene carbonate. In the present invention, the plasticizer is not limited to these, and various plasticizers can be used, and those commercially available as rubber plasticizers can also be used. These compounds can be expected to lower the viscosity of the acrylic block copolymer (A). Commercially available plasticizers include Thiocol TP (Morton), Adekasizer (registered trademark) O-130P, C-79, UL-100, P-200, RS-735 (Asahi Denka). Can be mentioned. Examples of other high molecular weight plasticizers include acrylic polymers, polypropylene glycol polymers, polytetrahydrofuran polymers, polyisobutylene polymers, and the like. Although not particularly limited, adipic acid derivatives, phthalic acid derivatives, glutaric acid derivatives, trimellitic acid derivatives, pyromellitic acid derivatives, polyester plasticizers, glycerin derivatives, epoxies, which are low volatility and low weight loss due to heating, are not particularly limited. Derivative polyester polymerization plasticizers, polyether polymerization plasticizers, and the like are preferable.

  The flexibility-imparting agent is not particularly limited, and examples thereof include softeners such as process oils; oils such as animal oils and vegetable oils; petroleum fractions such as kerosene, light oil, heavy oil, and naphtha. Examples of the softening agent include process oil, and more specifically, paraffin oil; naphthenic process oil; petroleum process oil such as aromatic process oil, and the like. Examples of vegetable oils include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, coconut oil, peanut oil, pine oil, tall oil and the like. A combination of more than one species can be used.

  The flame retardant is not particularly limited, and examples thereof include triphenyl phosphate, tricresyl phosphate, decabromobiphenyl, decabromobiphenyl ether, and antimony trioxide. These may be used alone or in combination.

  The pigment is not particularly limited, and for example, carbon black, titanium oxide, zinc sulfide, zinc oxide and the like can be used. These may be used alone or in combination.

<Method for producing thermoplastic elastomer composition>
There is no restriction | limiting in particular in the manufacturing method, and a thermoplastic elastomer composition can be manufactured by using a batch type kneading apparatus and a continuous kneading apparatus. As the batch kneader, for example, a mixing roll, a Banbury mixer, a pressure kneader, or a high shear mixer can be used. Moreover, as a continuous kneading apparatus, a single screw extruder, a twin screw extruder, a KCK extrusion kneader, etc. can be used. Furthermore, existing methods such as a method of mechanically mixing and shaping into pellets can be used.

  The temperature at the time of kneading for producing the thermoplastic elastomer composition is preferably a temperature at which the moldability is not lowered by the reaction between the acrylic block copolymer (A) and the acrylic polymer (B). The temperature at which the acrylic block copolymer (A) and the acrylic polymer (B) react and the moldability deteriorates is the type of hydroxyl group, the type of epoxy group, the amount introduced, the acrylic block copolymer (A). And the composition of the acrylic polymer (B), the compatibility of the acrylic block copolymer (A) and the acrylic polymer (B), and the like. For this reason, it changes so that it may react at desired temperature by changing these conditions. Here, the temperature at which the hydroxyl group reacts is preferably 200 ° C. or lower, more preferably 180 ° C. or lower, and even more preferably 150 ° C. or lower, in order to enable molding of the resulting composition. .

  It is preferable to knead at a temperature at which high molecular weight and cross-linking do not occur, but it is only necessary to be moldable even if high molecular weight or partial cross-linking occurs.

  In the case of powder slush molding, it is preferable to obtain the thermoplastic elastomer composition as a powder. As a method for obtaining a powder, the thermoplastic elastomer composition in the block state or pellet state processed by the above method is finely pulverized using an impact type fine pulverizer such as a turbo mill, a pin mill, a hammer mill, or a centrifugal mill. There is a way. The pulverization is usually performed at room temperature, but can be mechanically pulverized using a refrigerant or a cooling facility.

<Method of molding thermoplastic elastomer composition>
The composition obtained in the section of the method for producing a thermoplastic elastomer can be molded by various methods. For example, it can be applied to powder slush molding, injection molding, injection blow molding, blow molding, extrusion blow molding, extrusion molding, calendar molding, vacuum molding, press molding, etc., but powder slush molding is more preferably used. Here, the powder slush molding is a method in which the composition powder is poured into a molding die heated to a high temperature, melt-molded, and a molded body cooled and solidified after a certain time has passed. In powder slush molding, the composition needs to flow and be melt-molded even under no pressure, while the molded body after molding is exposed to a use environment of 100 ° C. or higher. For this reason, it is difficult to balance moldability and heat resistance.

  However, before molding, the composition of the present invention is in an unreacted state of the acrylic block copolymer (A) and the acrylic polymer (B), and has excellent meltability in the mold, while being cooled and solidified. After molding, the acrylic block copolymer (A) reacts with the acrylic polymer (B) within a predetermined time until the acrylic block copolymer (A) is polymerized or crosslinked. The heat resistance of is improved. From this, it can be said that it is a material suitable for powder slush molding.

  In addition, in powder slush molding, the acrylic block copolymer (A) has a high molecular weight or is cross-linked to improve the heat resistance after molding. However, the acrylic block copolymer (A) has a high molecular weight. In the case of imparting heat resistance, the acrylic block copolymer (A) after molding preferably has a number average molecular weight of 100,000 or more, more preferably 150,000 or more, More preferably, it is 200,000 or more. When the number average molecular weight is lower than 100,000, the effect of improving heat resistance is lowered. From such a point, it is preferable that the thermoplastic elastomer composition of the present invention uses an acrylic block copolymer (A) having a number average molecular weight of 40,000 or more.

  EXAMPLES Although this invention is demonstrated further in detail based on an Example, this invention is not limited only to these Examples. In the examples, BA, EA, HEA, and MMA represent n-butyl acrylate, ethyl acrylate, 2-hydroxyethyl acrylate, and methyl methacrylate, respectively. Moreover, the molecular weight described in the examples, the conversion rate of the polymerization reaction, and the evaluation of each physical property were performed according to the following methods.

<Molecular weight measurement method>
The molecular weight shown in this example was measured by the GPC analyzer shown below, and the molecular weight in terms of polystyrene was determined using chloroform as the mobile phase. As a system, a GPC system manufactured by Waters was used, and Shodex K-804 (polystyrene gel) manufactured by Showa Denko Co., Ltd. was used for the column.

<Method for measuring conversion rate of polymerization reaction>
The conversion rate of the polymerization reaction shown in this example was measured using the following analyzer and conditions.
Equipment used: Gas chromatography GC-14B manufactured by Shimadzu Corporation
Separation column: manufactured by J & W SCIENTIFIC INC, capillary column Supercoux-10, 0.35 mmφ × 30 m
Separation conditions: Initial temperature 60 ° C, hold for 3.5 minutes
Temperature increase rate 40 ° C / min
Final temperature 140 ° C, hold for 1.5 minutes
Injection temperature 250 ° C
Detector temperature 250 ° C
Sample preparation: The sample was diluted about 10 times with ethyl acetate, and butyl acetate or acetonitrile was used as an internal standard substance.

<Ethanol resistance test>
The ethanol resistance shown in the examples and comparative examples was measured under the following conditions.
The textured sheet produced in Examples and Comparative Examples was placed on a flat surface, and one drop of ethanol (manufactured by Wako Pure Chemical Industries, Ltd.) was dropped with a pipette, and left at room temperature for 24 hours. Thereafter, the surface was visually observed, and those having no trace were evaluated as “B” and those having whitening as “B”.

<Oil resistance test>
The oil resistance shown in the examples and comparative examples was measured under the following conditions.
The textured sheet produced in the examples and comparative examples was placed on a flat surface, and one drop of liquid paraffin (manufactured by Nacalai Tesque) was dropped with a pipette and left at room temperature for 24 hours. Thereafter, the liquid paraffin was wiped off with Kimwipe (registered trademark) (manufactured by Crecia Co., Ltd.), and the surface was visually observed.

<Heat resistance test>
The heat resistance shown in the examples and comparative examples was measured under the following conditions.
The textured sheet produced in Examples and Comparative Examples was left at 120 ° C. for 24 hours. Thereafter, the surface was visually observed, and those in which no change in the wrinkle pattern was observed were evaluated as “B”, and those in which the wrinkle pattern change was observed were marked as “C”.

<Urethane adhesion test>
According to the example, the composition was press-molded to prepare a skin material. A cartridge type polyurethane (manufactured by Air Tight Co., Ltd.) whose main component is 4,4′-diphenylmethane diisocyanate was applied on a metal plate, and a skin material was immediately placed on the foam and adhered. After 12 hours or more have passed (the foam is completely cured), the skin material is peeled off from the foamed urethane by hand, and the state of destruction is observed. The case where partial destruction occurred at the interface between the sheet and the urethane or complete destruction occurred was evaluated as x.

<Powder slash property test>
The melt fluidity (powder slash property) of the resin at the time of molding shown in this example and the comparative example was evaluated by the following method.
According to the examples and comparative examples, a mass of the composition was produced. A lump of the composition was put into a small pulverizer SK-M2 (manufactured by Kyoritsu Riko Co., Ltd.) cooled with dry ice, and pulverized while adding dry ice. The obtained powder was evaluated under the following conditions. The obtained powder was thinly spread on a leather metal plate heated to 200 ° C., and the molten state was visually observed.
Evaluation index: Evaluation in which powder completely melted: ◯, powder partially left unsettled: Δ, powder not melted: x

<Storage stability test>
The storage stability of the compositions shown in the examples and comparative examples was evaluated by the following method.
After the powder prepared for the powder slush test is left in an oven at 80 ° C. for 6 days, the powder slush test is performed, and the melt fluidity (powder slash property) before and after being left in the oven at 80 ° C. is observed. evaluated.
Evaluation index: Evaluation was made with a sample having a powder slush property of ◯ after being left for 6 days as ◯ and a sample having a powder slush property of being left after being left for 6 days as ×.

(Production Example 1)
(MMA-co-EA) -b- (BA-co-HEA) -b- (MMA-co-EA) type acrylic block copolymer (in this case, (MMA-co-EA) is obtained from MMA and EA. (BA-co-HEA) means a polymer block composed of BA and HEA, and (MMA-co-EA) -b- (BA-co-HEA) -b- (MMA-co- EA) means a block copolymer in which a (MMA-co-EA) block and a (BA-co-HEA) block are combined in the order described above, hereinafter referred to as “polymer 1”) Polymer 1 In order to obtain
After replacing the inside of the 5 L pressure-resistant reactor with nitrogen, 5.38 g (37 mmol) of copper bromide, 608 g (4.75 mol) of BA and 24 g (211 mmol) of HEA were charged, and stirring was started. Thereafter, a solution of 7.5 g (21 mmol) of diethyl 2,5-dibromoadipate as an initiator dissolved in 55 g of acetonitrile (nitrogen bubbling) was charged, and the inner solution was stirred for 30 minutes while being heated to 75 ° C. . When the internal temperature reached 75 ° C., 0.65 g (4 mmol) of the ligand pentamethyldiethylenetriamine was added to initiate polymerization of the acrylic polymer block.

  About 0.2 mL of the polymerization solution was sampled at regular intervals from the start of polymerization, and the conversion of BA and HEA was determined by gas chromatogram analysis. During polymerization, the polymerization rate was controlled by adding pentamethyldiethylenetriamine as needed. Pentamethyldiethylenetriamine was added twice in total (1.3 g in total) during the acrylic polymer block polymerization.

  When the conversion of BA was 99.0%, MMA 385 g (3.85 mol), EA 63 g (0.63 mol), copper chloride 3.71 g (37 mmol), pentamethyldiethylenetriamine 0.65 g (4 mmol) and Toluene (nitrogen bubbled) 830 g was added to initiate polymerization of the methacrylic polymer block.

  The conversion rate of MMA was determined in the same manner as in the acrylic polymer block polymerization. Sampling was performed when MMA was added, and the conversion rate of MMA was determined based on this. During polymerization, the polymerization rate was controlled by adding pentamethyldiethylenetriamine as needed. Pentamethyldiethylenetriamine was added a total of 6 times (3.9 g in total) during block polymerization of the methacrylic polymer. When the conversion rate of MMA was 94.4%, 1030 g of toluene was added, and the reaction was completed by cooling the reactor in a water bath.

  Toluene was added to the resulting reaction solution to dilute the polymer concentration to 25% by weight. To this solution, 17.1 g of p-toluenesulfonic acid monohydrate was added and stirred at room temperature for 3 hours, and the precipitated solid was removed by filtration.

  To the obtained polymer solution, 15.6 g of an adsorbent Kyoward 500SH (manufactured by Kyowa Chemical Co., Ltd.) was added, and the mixture was further stirred at room temperature for 1 hour. The adsorbent was filtered with a Kiriyama funnel to obtain a colorless and transparent polymer solution. This solution was dried to remove the solvent and residual monomer, and the target polymer 1 was obtained (number of hydroxyl groups per molecule (average): 10). When GPC analysis of the obtained polymer 1 was performed, the number average molecular weight Mn was 74110, and molecular weight distribution Mw / Mn was 1.53.

(Production Example 2)
(MMA-co-BA) -b-BA-b- (MMA-co-BA) type acrylic block copolymer (in this case, (MMA-co-BA) is a polymer block comprising MMA and BA, BA Means a polymer block composed of BA, and (MMA-co-BA) -b-BA-b- (MMA-co-BA) is a combination of (MMA-co-BA) block and BA block in the above order. In the following, in order to obtain the polymer 2, the following operation was carried out.

  After the inside of the polymerization vessel of the 5 L separable flask was purged with nitrogen, 5.7 g (40 mmol) of copper bromide was weighed and 59 g of acetonitrile (nitrogen bubbled) was added. After 30 minutes of heating and stirring at 70 ° C., 8.0 g (22 mmol) of diethyl 2,5-dibromoadipate initiator and 671 g (5.2 mol) of BA were added. The mixture was heated and stirred at 85 ° C., and 0.69 g (4.0 mmol) of ligand pentamethyldiethylenetriamine 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. The polymerization rate was controlled by adding pentamethyldiethylenetriamine as needed. When the conversion rate of BA was 94.5%, MMA 391 g (3.9 mol), BA 61 g (0.47 mol), copper chloride 4.0 g (40 mmol), pentamethyldiethylenetriamine 0.69 g (4.0 mmol) ) And 841 g of toluene (nitrogen bubbled). Similarly, conversion rates of MMA and BA were determined. When the conversion rate of MMA is 90.5% and the conversion rate of BA based on the BA concentration immediately after the addition of MMA / BA is 67.1%, 1500 g of toluene is added, and the reactor is cooled in a water bath to react. Ended.

  The reaction solution was diluted with 700 g of toluene, 16.0 g of p-toluenesulfonic acid monohydrate was added and stirred at room temperature for 3 hours, and the precipitated solid was removed by filtration. 16.0 g of adsorbent Kyoward 500SH (manufactured by Kyowa Chemical Co., Ltd.) was added to the obtained polymer solution, and the mixture was further stirred at room temperature for 1 hour. The adsorbent was filtered with a Kiriyama funnel to obtain a colorless and transparent polymer solution. This solution was dried to remove the solvent and residual monomer, and the target polymer 2 was obtained (number of hydroxyl groups per molecule: 0). When GPC analysis of the obtained polymer 2 was performed, the number average molecular weight Mn was 62600, and molecular weight distribution Mw / Mn was 1.44.

(Production Example 3)
(MMA-co-BA) -b-BA-b- (MMA-co-BA) type acrylic block copolymer-2 (in this case, (MMA-co-BA) is a polymer block composed of MMA and BA) , BA means a polymer block composed of BA, and (MMA-co-BA) -b-BA-b- (MMA-co-BA) means that (MMA-co-BA-) block and BA block are the above (Hereinafter referred to simply as “polymer 3”) In order to obtain the polymer 3, the following operation was performed.

  After the inside of the polymerization vessel of the 5 L separable flask was purged with nitrogen, 11.3 g (78.5 mol) of copper bromide was weighed and 180 mL of acetonitrile (dried with molecular sieves 3A and then bubbled with nitrogen) was added. After heating and stirring at 70 ° C. for 5 minutes, the mixture was cooled to room temperature again, and initiator 5.7 g (15.7 mol) of diethyl 2,5-dibromoadipate and 804.6 g (900.0 ml) of n-butyl acrylate were used. Was added. The mixture was heated and stirred at 80 ° C., and 1.6 ml (7.9 mmol) of ligand pentamethyldiethylenetriamine 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 of butyl acrylate was determined by gas chromatogram analysis. The polymerization rate was controlled by adding pentamethyldiethylenetriamine as needed. When the conversion of acrylate-n-butyl was 95%, methyl methacrylate, 345.7 g (369.3 ml), copper chloride, 7.8 g (78.5 mmol), pentamethyldiethylenetriamine, 1.6 ml (7. 9 mmol) and 1107.9 ml of toluene (dried with molecular sieves 3A and then bubbled with nitrogen). Similarly, the conversion rate of methyl methacrylate was determined. When the conversion rate of methyl methacrylate was 85% and the conversion rate of butyl acrylate-n-acid was 98%, 1500 ml of toluene was added, and the reaction was completed by cooling the reactor in a water bath. During the reaction, the polymerization solution was always green.

  The reaction solution was diluted with 4000 mL of toluene, 22.1 g of p-toluenesulfonic acid monohydrate was added, and the mixture was stirred at 23 ° C. for 3 hours. The precipitated insoluble part was removed by filtration with a Kiriyama funnel, 9.7 g of the adsorbent Kyoward 500SH was added to the polymer solution, and the mixture was further stirred at 23 ° C. for 3 hours. The adsorbent was filtered with a Kiriyama funnel to obtain a colorless and transparent polymer solution. This solution was dried to remove the solvent and residual monomer, and the target polymer 3 was obtained (number of hydroxyl groups per molecule: 0).

  When GPC analysis of the obtained polymer 3 was conducted, the number average molecular weight Mn was 119200, and the molecular weight distribution Mw / Mn was 1.51. Moreover, it was BA / MMA = 72/28 (weight%) when the compositional analysis by NMR was conducted.

Example 1
Polymer 1 obtained in Production Example 1: 100 parts by weight (30 g), all acrylic and 1.1 or more epoxy groups per molecule (approximate value 4 (from catalog)) Laboplast set at 100 ° C. in a ratio of 2.6 parts by weight of 10 parts by weight of polymer ARUFON UG4010 (manufactured by Toagosei Co., Ltd.) and zinc acetate (anhydrous) (manufactured by Wako Pure Chemical Industries, Ltd.) Using a mill 50C150 (blade shape: roller shape R60, Toyo Seiki Seisakusho Co., Ltd.), melt-kneading was performed at 100 rpm for 15 minutes to obtain a lump sample.

  The obtained sample was heat-pressed (compression molding machine NSF-50, manufactured by Kamito Metal Industry Co., Ltd.) for 8 minutes at a set temperature of 200 ° C. using a leather metal plate, and the thickness to which the leather texture was transferred A molded body for evaluation of 1 mm was obtained. These molded bodies were subjected to ethanol resistance, oil resistance, urethane adhesion, and heat resistance tests. Moreover, the powder slush property test was implemented with the powder which grind | pulverized the block sample obtained above, and this confirmed the melt fluidity at the time of shaping | molding. The results are shown in Table 1.

(Comparative Example 1)
The polymer 2 obtained in Production Example 2 was heat pressed (compression molding machine NSF-50, manufactured by Kondo Metal Industry Co., Ltd.) for 8 minutes at a set temperature of 200 ° C. using a leather metal plate, and a leather texture pattern. A molded product for evaluation having a thickness of 1 mm was transferred. These molded bodies were subjected to ethanol resistance, oil resistance, urethane adhesion, and heat resistance tests. Moreover, the powder slush property test was implemented using the powder which grind | pulverized the block sample obtained above, and, thereby, the melt fluidity at the time of shaping | molding was confirmed. The results are shown in Table 1.

  As can be seen from Table 1, the sample of polymer 2 having no hydroxyl group was excellent in powder slush moldability, but was inferior in heat resistance and urethane adhesion.

(Comparative Example 2)
Evaluation was performed in the same manner as in Comparative Example 2 except that Polymer 3 was used instead of Polymer 2 in Comparative Example 1. The results are shown in Table 1.

  As can be seen from Table 1, the sample of the polymer 3 having no hydroxyl group was excellent in heat resistance, but was inferior in powder slush moldability and urethane adhesion.

  As is clear from Table 1 (Example 1 and Comparative Examples 1 and 2), the thermoplastic elastomer composition of the present invention is not only excellent in powder slush moldability, but also the heat resistance of the obtained molded product is blocked. It can be seen that it is improved compared to that of the body alone. Moreover, it turns out that it is excellent also in ethanol resistance and oil resistance. Furthermore, it turns out that the storage stability is also good. Furthermore, when the obtained sheet is used as an automobile skin material, it is generally necessary to adhere the sheet to polyurethane or the like used as a base material, but the composition according to the present invention has good adhesion. It turns out that it shows sex.

The molded product obtained by molding the thermoplastic elastomer composition of the present invention is excellent in strain recovery, such as heat resistance, weather resistance, chemical resistance, oil resistance, adhesion, flexibility, wear resistance, etc. Therefore, the thermoplastic elastomer composition according to the present invention is a material that requires good tactile sensation, such as a skin material, a touch panel, a material whose appearance is important, an abrasion resistant material, an oil resistant material, a vibration damping material, It can be used as a material such as an adhesive material. In addition, the shape of the sheet, flat plate, film, small molded body, large molded body and other arbitrary shapes, and as parts such as panels, handles, grips, switches, etc. Can also be used as a sealing member. Although it does not restrict | limit especially as a use, The object for motor vehicles, household electrical appliances, or office electrical appliances are illustrated. For example, automotive skin materials, automotive tactile materials, automotive exterior materials, automotive panels, automotive handles, automotive grips, automotive switches, and home or office electrical appliance panels Examples thereof include switches for household or office electrical appliances. Among these, it is suitably used for an automobile interior skin.

Claims (21)

  An acrylic block copolymer (A) comprising a methacrylic polymer block (a) and an acrylic polymer block (b) and having an average of one or more hydroxyl groups per molecule, and an average of 1.1 per molecule A thermoplastic elastomer composition comprising an acrylic polymer (B) having at least one epoxy group. The acrylic block copolymer (A) has the general formula (1):

(In the formula, R ¹ is hydrogen or a methyl group and may be the same or different. R ² is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms or an aryl group, and 7 carbon atoms. 20 aralkyl group, _{or, - (O (CH 2)} n) p - (O (CH 2) m) q - in an in n and m is 2 to 4, p is 1 to 20, q is 0 2. The monomer unit (c) having a hydroxyl group represented by an integer of 20, n, m, p, and q may be the same or different from each other. Thermoplastic elastomer composition.   At least one monomer selected from the group consisting of acrylic polymer block (b) consisting of acrylic acid-n-butyl, ethyl acrylate, and 2-methoxyethyl acrylate, and these The thermoplastic elastomer composition according to claim 1 or 2, comprising 50 to 0% by weight of another acrylic acid ester and / or other vinyl monomer copolymerizable with the resin.   The thermoplastic elastomer according to any one of claims 1 to 3, wherein the acrylic block copolymer (A) has a number average molecular weight of 40,000 to 100,000 as measured by gel permeation chromatography. Composition.   The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography of the acrylic block copolymer (A) is 1.8 or less. The thermoplastic elastomer composition according to any one of claims 1 to 4.   The thermoplastic elastomer composition according to any one of claims 1 to 5, wherein the acrylic block copolymer (A) is a block copolymer produced by atom transfer radical polymerization.   The thermoplastic elastomer composition according to any one of claims 1 to 6, wherein the methacrylic polymer block (a) has a glass transition temperature of 25 to 130 ° C.   The thermoplastic elastomer composition according to any one of claims 1 to 7, wherein the acrylic polymer (B) has a weight average molecular weight of 30,000 or less.   The thermoplastic elastomer composition according to any one of claims 1 to 8, wherein the acrylic polymer (B) has a glass transition temperature of 100 ° C or lower.   The acrylic polymer (B) is at least one monomer selected from the group consisting of acrylic acid-n-butyl, ethyl acrylate, and 2-methoxyethyl acrylate, The thermoplastic elastomer composition according to any one of claims 1 to 9, comprising 50 to 0% by weight of another polymerizable acrylic ester and / or other vinyl monomer.   The thermoplastic elastomer composition according to any one of claims 1 to 10, wherein the acrylic polymer (B) has a weight average molecular weight of 500 to 10,000.   The thermoplastic elastomer composition according to any one of claims 1 to 11, wherein the acrylic polymer (B) has a viscosity of 35,000 mPa · s or less.   The thermoplastic elastomer according to any one of claims 1 to 12, wherein 1 to 30 parts by weight of the acrylic polymer (B) is added to 100 parts by weight of the acrylic block copolymer (A). Composition.   The thermoplastic elastomer composition according to any one of claims 1 to 13, wherein 5 to 200 parts by weight of a filler is further added to 100 parts by weight of the acrylic block copolymer.   The thermoplastic elastomer composition according to any one of claims 1 to 14, wherein 0.1 to 20 parts by weight of a lubricant is further added to 100 parts by weight of the acrylic block copolymer.   The thermoplastic elastomer composition according to any one of claims 1 to 15, wherein 5 to 30 parts by weight of a plasticizer is further added to 100 parts by weight of the acrylic block copolymer.   The thermoplastic elastomer composition according to any one of claims 1 to 16, wherein 0.01 to 10 parts by weight of a curing accelerator is further added to 100 parts by weight of the acrylic block copolymer.   18. The thermoplastic elastomer composition according to claim 17, wherein the curing accelerator is a thermal latent acid catalyst that exhibits activity during thermoforming.   A thermoplastic elastomer composition for powder slush molding, comprising the composition according to any one of claims 1 to 18.   A molded article comprising the composition according to any one of claims 1 to 19 formed by powder slush molding. An automotive interior skin comprising the composition according to any one of claims 1 to 19 formed by powder slush molding.