Thermoplastic elastomer composition for multilayer molding, multilayer molded article, and method for manufacturing a multilayer molded article.

Abstract

A thermoplastic elastomer composition for multilayer molding and to be subjected to thermal fusion bonding through injection molding, the thermoplastic elastomer composition comprising 100 parts by mass of a hydrogenated block copolymer (a-1), 10-100 parts by mass of a polypropylene-based resin (b), and 50-300 parts by mass of a nonaromatic softening agent (c), and further comprising a hydrogenated block copolymer (a-2), wherein the hydrogenated block copolymers (a-1) and (a-2) are each a non-modified hydrogenated block copolymer, the contained amount of the hydrogenated block copolymer (a-2) is 5-70 mass% with respect to the total amount of the components (a-1), (a-2), (b), and (c), and the hydrogenated block copolymers (a-1) and (a-2) each have a specific structure.

Description

[Technical Field]

[0001] The present invention relates to a thermoplastic elastomer composition for multilayer molding, a multilayer molded article, and a method for manufacturing a multilayer molded article. [Background technology]

[0002] Conventionally, polar group-containing thermoplastic resins, also known as engineering plastics, have been used in many fields due to their excellent heat resistance and mechanical properties. For example, they are often used as multilayer molded articles in which a soft material is bonded to the surface or part of the material using the aforementioned polar group-containing thermoplastic resin as the base material. Examples include the surface materials of automobile interiors, grips, cushioning materials, and sealing components such as gaskets.

[0003] Methods for bonding a soft material to a thermoplastic resin substrate containing polar groups include, for example, bonding with an adhesive or bonding by heat fusion during molding. While methods using adhesives allow for a firm bond between the flexible material and the substrate, they have the drawback of slowing down production speed because they require a curing process in addition to the adhesive application process.

[0004] On the other hand, heat-seal bonding methods include injection molding techniques such as insert molding and two-color molding. These injection molding bonding methods allow for simultaneous heat sealing during molding, significantly improving production speed, and have become increasingly common in recent years.

[0005] However, in heat bonding methods, the affinity of the flexible material to be bonded to a thermoplastic resin substrate containing polar groups is an important factor, and when a non-polar composition is used as the flexible material, the adhesive strength is weak, which is a problem. Therefore, in order to improve the adhesive strength, heat bonding compositions containing functional group-containing modified components as flexible materials, and technologies related to adhesives using such compositions have been proposed. For example, Patent Document 1 discloses a thermoplastic elastomer composition containing a hydrogenated thermoplastic styrene elastomer, a hydrocarbon-based rubber softener, polypropylene, a thermoplastic polyurethane elastomer, and an acid-modified hydrogenated styrene elastomer. Furthermore, Patent Document 2 discloses a thermoplastic polymer composition containing a thermoplastic elastomer, a polyvinyl acetal resin, and / or a polar group-containing polypropylene resin, and a technology relating to an adhesive comprising the thermoplastic polymer composition and an insert member. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2009-209273 [Patent Document 2] Japanese Patent Publication No. 2014-168940 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] However, the thermoplastic elastomer composition disclosed in Patent Document 1 contains a maleic anhydride-modified styrene elastomer as the acid-modified hydrogenated styrene elastomer, but it generates a pungent odor during heat processing and in the subsequent molded product. Therefore, it has the problem of being unsuitable for applications where people stay for long periods of time, such as medical applications, automotive interior materials, and housing materials. In addition, when acid modification is performed, the modification process is increased, unreacted free maleic acid remains as an impurity, and discoloration occurs due to maleic acid oligomers, among other problems. In addition, in the thermoplastic polymer composition disclosed in Patent Document 2, it contains a polyvinyl acetal resin and / or a polar group-containing polypropylene-based resin. The side chain of the polyvinyl acetal resin is likely to come off during hot processing, and a strong odor is generated due to its decomposition reaction, so it has a problem of being extremely bad in terms of the working environment. Further, the polar group-containing polypropylene-based resin is acid-modified with maleic anhydride, and like the thermoplastic elastomer composition disclosed in Patent Document 1, it has a problem of generating a pungent odor. As described above, the composition for thermal adhesion composed of the conventionally proposed thermoplastic elastomer composition and thermoplastic polymer composition has a problem that there is room for improvement from the viewpoints of odor, coloring, etc.

[0008] Therefore, in the present invention, in view of the problems of the above-described prior art, an object is to provide a thermoplastic elastomer composition and a multilayer molded body that have good odor and taste in practical use and are excellent in moldability, thermal adhesion strength, and mechanical strength.

Means for Solving the Problems

[0009] As a result of intensive studies to solve the above-described problems of the prior art, the present inventors have found that a thermoplastic elastomer composition containing a hydrogenated block copolymer having a predetermined structure, a polypropylene-based resin, and a non-aromatic softening agent in a predetermined ratio can solve the above-described problems of the prior art, and have completed the present invention. That is, the present invention is as follows.

[0010] 〔1〕 100 parts by mass of a hydrogenated block copolymer (a-1), 10 to 100 parts by mass of a polypropylene-based resin (b), 50 to 300 parts by mass of a non-aromatic softening agent (c), and containing, Furthermore, it is a thermoplastic elastomer composition for multi-layer molding that contains a hydrogenated block copolymer (a-2), and both the hydrogenated block copolymer (a-1) and the hydrogenated block copolymer (a-2) are non-modified hydrogenated block copolymers, and is heat-sealed by injection molding. The content of the hydrogenated block copolymer (a-2) is 5 to 70% by mass based on the total amount of the components (a-1), (a-2), (b), and (c). The hydrogenated block copolymer (a-1) satisfies the following requirements (1-1) to (1-4). The hydrogenated block copolymer (a-2) satisfies the following requirements (2-1) to (2-6). A thermoplastic elastomer composition for multi-layer molding. (1-1): It contains a polymer block A1 mainly composed of one or more styrene and a polymer block B1 mainly composed of one or more conjugated diene monomer units. (1-2): The content of all styrene is 15% by mass or more and less than 35% by mass. (1-3): The weight average molecular weight is 150,000 to 550,000. (1-4): 50 mol% or more of the double bonds of the conjugated diene monomer units are hydrogenated. (2-1): It contains a polymer block A2 mainly composed of one or more styrene and a polymer block B2 mainly composed of one or more conjugated diene monomer units. (2-2): The content of styrene in the polymer block A2 is 50% by mass or more. (2-3): The content of all styrene is 35% to 70% by mass. (2-4): The weight average molecular weight is 30,000 or more and less than 150,000. (2-5): The amount of vinyl bonds before hydrogenation in the conjugated diene monomer units in the polymer block B2 is 60 mol% to 95 mol%. (2-6): 50 mol% or more of the double bonds of the conjugated diene monomer units are hydrogenated. [2] The hydrogenated block copolymer (a-2) is at least two styrene It comprises polymer block A2 mainly composed of and polymer block B2 mainly composed of at least two conjugated diene monomer units, At least one of the polymer blocks B2 is located at the end of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the end is 1 to 10% by mass in the hydrogenated block copolymer (a-2). It does not have a peak with a weight-average molecular weight of 250,000 or more. The thermoplastic elastomer composition for multilayer molding described in [1] above. [3] In the polymer block A2 of the hydrogenated block copolymer (a-2) styrene A thermoplastic elastomer composition for multilayer molding according to [1] or [2] above, wherein the content of is 90% by mass or more. [4] The total of the hydrogenated block copolymer (a-2) styrene A thermoplastic elastomer composition for multilayer molding according to any one of [1] to [3] above, wherein the content of exceeds 40% by mass and is 70% by mass or less. [5] In the hydrogenated block copolymer (a-1), A thermoplastic elastomer composition for multilayer molding according to any one of [1] to [4], wherein the amount of vinyl bond in the conjugated diene monomer unit before hydrogenation is 30 mol% to 50 mol%. [6] A multilayer molded article having a thermoplastic elastomer composition layer for multilayer molding according to any one of [1] to [5] above, and a polar group-containing thermoplastic resin layer. [7] An polarity group-containing thermoplastic resin layer, A thermoplastic elastomer composition layer comprising a hydrogenated block copolymer (a), a polypropylene resin (b), and a non-aromatic softener (c), A multilayer molded body having, The thermoplastic elastomer composition layer is provided in contact with the polar group-containing thermoplastic resin layer, The hydrogenated block copolymer (a) does not contain a modifying group. The hydrogenated block copolymer (a) is styrene A hydrogenated block copolymer which is a hydrogenated product of a block copolymer having a conjugated diene monomer unit, The molecular weight peaks determined by GPC are one or more in the range of 30,000 to less than 150,000 and one or more in the range of 150,000 to 550,000. Hydrogenated block copolymers whose molecular weight peak measured by the aforementioned GPC is between 30,000 and less than 150,000 styrene The content is 35% to 70% by mass, and the amount of vinyl bond in the conjugated diene monomer unit before hydrogenation is 60 mol% to 95 mol%, The molecular weight peaks measured by the aforementioned GPC are for hydrogenated block copolymers with a total molecular weight of 150,000 to 550,000. styrene The content is between 15% by mass and less than 35% by mass. The hydrogenation rate of the double bond in the conjugated diene monomer unit is 50 mol% or more. Multilayered molded body. [8] The hydrogenated block copolymer (a) consists of hydrogenated block copolymer (a-1) and hydrogenated block copolymer (a-2), The above (a-1) satisfies the requirements of (1-1) to (1-4) below, The above (a-2) satisfies the requirements of (2-1) to (2-6) below, The thermoplastic elastomer composition layer contains (a-1) 100 parts by mass, (b) 10 to 100 parts by mass, and (c) 50 to 300 parts by mass. The multilayer molded article according to [7], wherein the content of (a-2) in the thermoplastic elastomer composition layer is 5 to 70% by mass of the total amount of components (a-1), (a-2), (b), and (c). (1-1): One or more styrene It contains polymer block A1 mainly composed of and polymer block B1 mainly composed of one or more conjugated diene monomer units. (1-2):All styrene The content is 15% by mass or more and less than 35% by mass. (1-3): The weight-average molecular weight is between 150,000 and 550,000. (1-4): More than 50 mol% of the double bonds in the conjugated diene monomer units are hydrogenated. (2-1): One or more styrene It contains polymer block A2 mainly composed of [a certain substance] and polymer block B2 mainly composed of one or more conjugated diene monomer units. (2-2): In polymerization block A2 styrene The content is 50% by mass or more. (2-3):All styrene The content is between 35% and 70% by mass. (2-4): The weight-average molecular weight is 30,000 or more and less than 150,000. (2-5): The amount of vinyl bonds in the conjugated diene monomer units in polymer block B2 before hydrogenation is 60 mol% to 95 mol%. (2-6): More than 50 mol% of the double bonds in the conjugated diene monomer units are hydrogenated. [9] The hydrogenated block copolymer (a-2) at least two styrene The polymer comprises polymer block A2 mainly composed of and polymer block B2 mainly composed of at least two conjugated diene monomer units, wherein at least one polymer block B2 is located at the end of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the end is 1 to 10% by mass in the hydrogenated block copolymer (a-2). all styrene The content is greater than 40% by mass and less than or equal to 70% by mass. It does not have a peak with a weight-average molecular weight of 250,000 or more. The multilayer molded body described in [8] above.

[10] In the polymer block A2 of the hydrogenated block copolymer (a-2) styrene A multilayer molded article according to [8] or [9], wherein the content of is 90% by mass or more.

[11] The multilayer molded article according to any one of [6] to

[10] , wherein the polar group-containing thermoplastic resin is at least one selected from the group consisting of polycarbonate resin, ABS resin, polyester resin, acrylic resin, and mixtures thereof.

[12] The hydrogenated block copolymer (a-1) is A multilayer molded article according to any one of [8] to

[11] , wherein the amount of vinyl bond in the conjugated diene monomer unit before hydrogenation is 30 mol% to 50 mol%.

[13] A thermoplastic elastomer composition for use in a multilayer molded article according to any one of the above [6] to

[12] , The multilayer molded body is formed by heat-sealing the polar group-containing thermoplastic resin layer and the thermoplastic elastomer composition layer by injection molding. Thermoplastic elastomer composition.

[14] The aforementioned [6 squares or 〔12〕 A method for manufacturing a multilayer molded article according to any one of the following: A step of molding the polar group-containing thermoplastic resin to obtain a molded article, With the molded body placed in the mold, in the gap between the mold and the molded body,

[13] The process involves injecting and heat-sealing the thermoplastic elastomer composition described above. A method for manufacturing a multilayered molded body. [Effects of the Invention]

[0011] According to the present invention, thermoplastic elastomer compositions and multilayer laminates can be obtained that have practically good odor and color, and excellent moldability, heat adhesion strength, and mechanical strength. [Modes for carrying out the invention]

[0012] The embodiments for carrying out the present invention (hereinafter referred to as "this embodiment") will be described in detail below. The following embodiments are illustrative examples for explaining the present invention and do not limit the present invention to the following content. The present invention can be implemented in various modifications within the scope of its gist.

[0013] [Thermoplastic elastomer composition] The thermoplastic elastomer composition of this embodiment is a thermoplastic elastomer composition for multilayer molding, which is heat-fused with other components by injection molding. 100 parts by mass of hydrogenated block copolymer (a-1) and Polypropylene resin (b) 10 to 100 parts by mass, 50 to 300 parts by mass of a non-aromatic softening agent (c), It contains, Furthermore, it contains a hydrogenated block copolymer (a-2), and both the hydrogenated block copolymer (a-1) and the hydrogenated block copolymer (a-2) are unmodified hydrogenated block copolymers. The content of the hydrogenated block copolymer (a-2) is 5 to 70% by mass relative to the total amount of components (a-1), (a-2), (b), and (c). The hydrogenated block copolymer (a-1) satisfies the requirements (1-1) to (1-4) below, and the hydrogenated block copolymer (a-2) satisfies the requirements (2-1) to (2-6) below. (1-1): Contains polymer block A1 mainly composed of one or more vinyl aromatic monomer units and polymer block B1 mainly composed of one or more conjugated diene monomer units. (1-2): The total content of vinyl aromatic monomer units is 15% by mass or more and less than 35% by mass. (1-3): The weight-average molecular weight is between 150,000 and 550,000. (1-4): More than 50 mol% of the double bonds in the conjugated diene monomer units are hydrogenated. (2-1): Contains polymer block A2 mainly composed of one or more vinyl aromatic monomer units and polymer block B2 mainly composed of one or more conjugated diene monomer units. (2-2): The content of vinyl aromatic monomer units in polymer block A2 is 50% by mass or more. (2-3): The total content of vinyl aromatic monomer units is 35% to 70% by mass. (2-4): The weight-average molecular weight is 30,000 or more and less than 150,000. (2-5): The amount of vinyl bonds in the conjugated diene monomer units in polymer block B2 before hydrogenation is 60 mol% to 95 mol%. (2-6): More than 50 mol% of the double bonds in the conjugated diene monomer units are hydrogenated. By having the above configuration, a thermoplastic elastomer composition is obtained that has practically good odor and color, and excellent moldability, heat adhesion strength, and mechanical strength. The following provides a detailed explanation of each component.

[0014] (Hydrogenated block copolymer (a-1)) The thermoplastic elastomer composition of this embodiment contains a hydrogenated block copolymer (a-1). Hydrogenated block copolymer (a-1) is a hydrogenated block copolymer obtained by hydrogenating a block copolymer containing polymer block A1 mainly composed of one or more vinyl aromatic monomer units and polymer block B1 mainly composed of one or more conjugated diene monomer units (as per requirement (1-1) above). Hydrogenated block copolymer (a-1) is a so-called "unmodified" copolymer that does not have functional groups derived from vinyl aromatic compounds or conjugated diene compounds. Because it is unmodified, there is no contamination from impurities from unreacted products, resulting in a copolymer with less odor. Furthermore, "unmodified" means that the hydrogenated block copolymer (a-1) does not contain modified groups formed by a predetermined modifying agent, and if the hydrogenated block copolymer (a-1) is obtained through a coupling reaction with a coupling agent, it is deemed to satisfy the requirement of "unmodified" if it contains Si atoms and O atoms derived from the coupling agent. Thus, in this embodiment, a distinction is made between whether the heteroatom-containing atomic group exists as a coupling agent residue or is introduced by a modifying agent. This is thought to be influenced by the fact that coupling agent residues tend to be located in the center of the copolymer, while modifying agents tend to be introduced to the ends or side chains of the copolymer. In order to provide a thermoplastic elastomer composition with practically good odor and color, it is desirable to minimize the liberation of functional groups. However, in the case of residues introduced in the center as a coupling agent, the liberation of functional groups tends to be less likely because the polymer chain ends are bonded to the functional groups by the coupling reaction and / or due to steric hindrance by the copolymer chain. In contrast, when a modifying agent is reacted to the ends or side chains of the copolymer, the liberation of functional groups is more likely to occur, which tends to cause odor and color. In particular, in the case of so-called secondary modified products in which the copolymer and modifying agent are mixed and reacted in an extruder, modifying groups are often introduced with maleic anhydride or epoxy, and in this case, carboxyl group-containing compounds and epoxy group-containing compounds tend to be easily desorbed, which tends to cause odor and color. Furthermore, in the case of coupling reactions at the end of polymerization, unreacted substances can be almost completely removed in subsequent finishing processes of the copolymer, such as solvent removal. In contrast, in the case of secondary modified products, complete removal is difficult, and there tends to be a large amount of unreacted residue, which can easily affect odor and color. Traditionally, the purpose of modification has been to improve adhesion with other components, but the inventors conceived of designing a hydrogenated block copolymer structure that ensures good adhesion even without modification. Primarily, the structure of the hydrogenated block copolymer (a-2), described later, provides the effect of facilitating heat fusion with other components during multilayer molding. Modified groups in hydrogenated block copolymers can be identified by NMR and IR analysis.

[0015] The polymer block A1, which mainly consists of vinyl aromatic monomer units, means that the content of vinyl aromatic monomer units in polymer block A1 exceeds 50% by mass, and from the viewpoint of mechanical strength and heat deformation resistance, it is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0016] Similarly, polymer block B1 mainly composed of the conjugated diene monomer units means that the content of conjugated diene monomer units in polymer block B1 exceeds 50% by mass, and from the viewpoint of flexibility and softener retention, it is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0017] In this embodiment, the naming of each monomer unit constituting the block copolymer follows the naming of the monomer from which the monomer unit is derived. For example, "vinyl aromatic monomer unit" refers to a polymer unit produced as a result of polymerizing a vinyl aromatic compound which is a monomer, and its structure is a molecular structure in which the two carbon atoms of a substituted ethylene group derived from a substituted vinyl group are bonded sites. Furthermore, a "conjugated diene monomer unit" refers to a polymer constituent unit resulting from the polymerization of conjugated diene compounds, which are monomers. Its structure is a molecular structure in which the two carbon atoms of the olefin derived from the conjugated diene compound form the bonding sites.

[0018] In this embodiment, the vinyl aromatic compound that can be used to form vinyl aromatic monomer units in polymer block A1 refers to a compound having a vinyl group and an aromatic ring. Examples of vinyl aromatic compounds include, but are not limited to, styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N,N-dimethyl-p-aminoethylstyrene, and N,N-diethyl-p-aminoethylstyrene. Among these, styrene, α-methylstyrene, and divinylbenzene are preferred from the viewpoint of polymerizability. These vinyl aromatic compounds may be used individually or in combination of two or more.

[0019] The conjugated diene compounds that can be used to form conjugated diene monomer units in polymer block B1 are diolefins having a pair of conjugated double bonds (two double bonds bonded in a conjugated manner). The conjugated diene compounds are not limited to the following, but examples include 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, and 1,3-hexadiene. Among these, 1,3-butadiene and 2-methyl-1,3-butadiene (isoprene) are preferably used from the viewpoint of polymerizability. These conjugated diene compounds may be used individually or in combination of two or more.

[0020] The hydrogenated block copolymer (a-1) has a structure that is not limited to the following, but for example, is represented by the following general formulas (1) to (7). Furthermore, the hydrogenated block copolymer (a-1) may be a mixture containing multiple types of copolymers having the structures represented by the following general formulas (1) to (7) in any proportion. (A1-B1) n (1) A1-(B1-A1) n (2) B1-(A1-B1) n (3) [(B1-A1) n ] m -Z (4) [(A1-B1) n ] m -Z (5) [(B1 - A1) n - B1] m - Z(6) [(A1 - B1) n - A1] m - Z(7)

[0021] In general formulas (1) to (7), A1 is a polymer block mainly composed of vinyl aromatic monomer units, and B1 is a polymer block mainly composed of conjugated diene monomer units. The boundary line between polymer block A1 and polymer block B1 does not necessarily need to be clearly distinguished. Also, n is an integer of 1 or more, preferably an integer of 1 to 5. m is an integer of 2 or more, preferably an integer of 2 to 11, more preferably an integer of 2 to 8. Z represents a coupling agent residue. Here, the coupling residue means the residue after bonding of a coupling agent used to bond a plurality of copolymers of conjugated diene monomer units and vinyl aromatic monomer units between polymer block A1 - polymer block A1, between polymer block B1 - polymer block B1, or between polymer block A1 - polymer block B1. Examples of the coupling agent include, but are not limited to, silicon halide compounds and acid esters described later.

[0022] In general formulas (1) to (7), the vinyl aromatic monomer units in polymer block A1 and polymer block B1 may be uniformly distributed or taper - shaped distributed. Also, when polymer block A1 and polymer block B1 are copolymer blocks of vinyl aromatic monomer units and conjugated diene monomer units, there may be a plurality of portions where the vinyl aromatic monomer units in the copolymer block are uniformly distributed and a plurality of portions where they are taper - shaped distributed. Further, in the copolymer block portion, there may be a plurality of portions with different contents of vinyl aromatic monomer units coexisting.

[0023] The content of all vinyl aromatic monomer units in the hydrogenated block copolymer (a - 1) is 15% by mass or more and less than 35% by mass (the above requirement (1 - 2)). From the viewpoint of mechanical strength, flexibility, resilience, and rebound elasticity of the thermoplastic elastomer composition of this embodiment, the content is preferably 17% by mass or more, more preferably 19% by mass or more, even more preferably 21% by mass or more, and even more preferably 23% by mass or more. Furthermore, it is preferably 34% by mass or less, and more preferably 33% by mass or less. Mechanical strength and resilience are necessary properties for material strength and deformation prevention, while flexibility and rebound elasticity are properties related to tactile feel. Therefore, when the thermoplastic elastomer composition of this embodiment is used in grips, surface materials, and sealing materials, it is preferable to design the content of total vinyl aromatic monomer units in the hydrogenated block copolymer (a-1) to be within a range suitable for these applications.

[0024] When the total vinyl aromatic monomer unit content in the hydrogenated block copolymer (a-1) is 15% by mass or more, the mechanical strength and heat deformation resistance of the thermoplastic elastomer composition of this embodiment tend to improve, and when the total vinyl aromatic monomer unit content is less than 35% by mass, the flexibility, resilience, and rebound elasticity of the thermoplastic elastomer composition of this embodiment tend to improve. The total vinyl aromatic monomer unit content can be controlled to the above numerical range by adjusting the amount of monomer added during the polymerization process of the hydrogenated block copolymer (a-1), and can be calculated using the absorption intensity at 262 nm with an ultraviolet spectrophotometer as described in the examples described later.

[0025] The weight-average molecular weight of the hydrogenated block copolymer (a-1) is 150,000 to 550,000 (as per the above requirements (1-3)). From the viewpoint of heat deformation resistance, it is 150,000 or more, preferably 170,000 or more, more preferably 190,000 or more, and even more preferably 210,000 or more. It is also preferably 500,000 or less, more preferably 450,000 or less, even more preferably 400,000 or less, even more preferably 350,000 or less, and even more preferably 300,000 or less. When the weight-average molecular weight of the hydrogenated block copolymer (a-1) is 150,000 or more, the thermoplastic elastomer composition of this embodiment tends to have good heat deformation resistance and recovery properties. When the weight-average molecular weight of the hydrogenated block copolymer (a-1) is 550,000 or less, the thermoplastic elastomer composition of this embodiment exhibits good fluidity and sufficient moldability.

[0026] The molecular weight distribution (Mw / Mn) of the hydrogenated block copolymer (a-1) is preferably 1.01 to 5.0, more preferably 1.01 to 4.0, and even more preferably 1.01 to 3.0. A better mechanical strength tends to be obtained when the molecular weight distribution of the hydrogenated block copolymer (a-1) is between 1.01 and 5.0. The shape of the molecular weight distribution curve of the hydrogenated block copolymer (a-1) measured by gel permeation chromatography (hereinafter sometimes referred to as GPC) is not particularly limited. It may have a polymodal molecular weight distribution with two or more peaks, or a monomodal molecular weight distribution with one peak. Furthermore, the weight-average molecular weight (Mw) and molecular weight distribution [Mw / Mn; ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn)] of the hydrogenated block copolymer (a-1) can be determined based on the molecular weight of the peaks in the chromatogram measured by gel permeation chromatography (GPC) using the method described in the examples below, using a calibration curve (created using the peak molecular weight of standard polystyrene) obtained from measurements of commercially available standard polystyrene.

[0027] The microstructure (amount of cis, trans, and vinyl bonds) of polymer block B1 in hydrogenated block copolymer (a-1) can be arbitrarily controlled by using modifiers such as polar compounds during the polymerization process of hydrogenated block copolymer (a-1). The adjusting agents will be discussed later.

[0028] The amount of vinyl bond in the conjugated diene monomer units before hydrogenation in the hydrogenated block copolymer (a-1) is preferably 30 mol% or more, more preferably 31 mol% or more, even more preferably 31 mol% or more, and even more preferably 32 mol% or more. The preferred upper limit is 50 mol% or less, more preferably 47 mol% or less, and even more preferably 44 mol% or less. When the amount of vinyl bonds in the conjugated diene monomer units in the hydrogenated block copolymer (a-1) before hydrogenation is 30 mol% or more, the compatibility between the hydrogenated block copolymer (a-1) and the polypropylene resin (b) described later tends to improve, and when the amount of vinyl bonds in the conjugated diene monomer units before hydrogenation is 50 mol% or less, the mechanical strength of the thermoplastic elastomer composition of this embodiment tends to improve. In this specification, the term "amount of vinyl bonds before hydrogenation" is used because the bonds can no longer be called "vinyl bonds" after hydrogenation. This does not mean that the measurement must be performed on the copolymer before hydrogenation. The bonding mode of conjugated dienes can also be determined from the structure after hydrogenation, so it is possible to calculate the amount of vinyl bonds "before hydrogenation" by examining the structure after hydrogenation.

[0029] In this embodiment, the vinyl bond amount is, for example, in the case of butadiene, the ratio of the total molar amount of conjugated diene monomer units incorporated with 1,2-bonds and 3,4-bonds to the total molar amount of conjugated diene monomer units incorporated with 1,2-bonds, 3,4-bonds and 1,4-bonds before hydrogenation. Furthermore, after hydrogenation, the ratio of the total molar amount of conjugated diene monomer units incorporated with 1,2-bonds before hydrogenation, 1,2-bonds after hydrogenation, 3,4-bonds before hydrogenation, 3,4-bonds after hydrogenation, 1,4-bonds before hydrogenation, and 3,4-bonds after hydrogenation to the total molar amount of conjugated diene monomer units incorporated with 1,2-bonds before hydrogenation, 1,2-bonds after hydrogenation, 3,4-bonds before hydrogenation, 3,4-bonds after hydrogenation, 1,4-bonds before hydrogenation, and 1,4-bonds after hydrogenation is equal to the amount of vinyl bonds in the conjugated diene monomer units before hydrogenation. Therefore, the amount of vinyl bonds in the conjugated diene monomer units before hydrogenation can be measured by nuclear magnetic resonance spectroscopy (NMR) using the block copolymer after hydrogenation, and specifically by the method described in the examples below.

[0030] The hydrogenation rate of the aliphatic double bonds derived from the conjugated diene compound in the hydrogenated block copolymer (a-1), i.e., the double bonds of the conjugated diene monomer unit, is 50% or more (as per the above requirements (1-4)), preferably 60% or more, and more preferably 70% or more. If the hydrogenation rate is 50% or more, the thermoplastic elastomer composition of this embodiment tends to more effectively suppress the deterioration of mechanical properties due to thermal degradation (oxidative degradation). Furthermore, if the hydrogenation rate is 70% or more, the thermoplastic elastomer composition of this embodiment tends to obtain better weather resistance. The upper limit of the hydrogenation rate is not particularly limited, but it is preferably 100% or less, and more preferably 99% or less. The hydrogenation rate of the double bonds of the conjugated diene monomer units in the hydrogenated block copolymer (a-1) can be controlled within the above numerical range by adjusting the type and amount of hydrogenation catalyst used and the hydrogenation conditions, and can be measured by the method described in the examples below.

[0031] By incorporating the organic peroxide (e), described later, into the thermoplastic elastomer composition of this embodiment, partial crosslinking is possible during the process of melt-kneading the thermoplastic elastomer composition in an extruder. The thermoplastic elastomer composition layer constituting the multilayer molded body of this embodiment, described later, does not necessarily need to be crosslinked, but it may be crosslinked in applications where there is a high demand for suppressing permanent deformation. When partially crosslinking the thermoplastic elastomer composition of this embodiment using the organic peroxide (e), from the viewpoint of heat resistance, the hydrogenation rate of the aliphatic double bond derived from the conjugated diene compound in the hydrogenated block copolymer (a-1) must be 50% or more, preferably 60% or more, and from the viewpoint of processability and crosslinking reactivity, preferably 90% or less, and more preferably 85% or less.

[0032] The hydrogenation rate of aromatic double bonds based on vinyl aromatic monomer units in the hydrogenated block copolymer (a-1) is not particularly limited, but is preferably 50% or less, more preferably 30% or less, and even more preferably 20% or less.

[0033] (Hydrogenated block copolymer (a-2)) The thermoplastic elastomer composition of this embodiment contains a hydrogenated block copolymer (a-2). The hydrogenated block copolymer (a-2) is a hydrogenated block copolymer obtained by hydrogenating a block copolymer comprising polymer block A2 mainly consisting of one or more vinyl aromatic monomer units and polymer block B2 mainly consisting of one or more conjugated diene compound monomer units (as per requirement (2-1) above).

[0034] The hydrogenated block copolymer (a-2) has a total vinyl aromatic monomer unit content of 35% to 70% by mass (requirement (2-3) above). Furthermore, the weight-average molecular weight of the hydrogenated block copolymer (a-2) is 30,000 or more and less than 150,000 (requirement (2-4) above). Additionally, the amount of vinyl bonds in the conjugated diene monomer units in polymer block B2 before hydrogenation is 60 mol% to 95 mol% (requirement (2-5) above).

[0035] Hydrogenated block copolymer (a-2) is an unmodified block copolymer that does not have functional groups derived from vinyl aromatic compounds and conjugated diene compounds. Because hydrogenated block copolymer (a-2) is unmodified, a thermoplastic elastomer composition can be obtained that is free from odor, discoloration, and impurities from unreacted materials. Furthermore, "unmodified" means that the hydrogenated block copolymer (a-2) does not contain modified groups formed by a predetermined modifying agent, and if the hydrogenated block copolymer (a-2) is obtained through a coupling reaction with a coupling agent, it is deemed to satisfy the requirement of "unmodified" if it contains Si atoms and O atoms derived from the coupling agent.

[0036] The thermoplastic elastomer composition of this embodiment contains a hydrogenated block copolymer (a-2) with a specific structure that satisfies requirements (2-1) to (2-6), making it possible to heat-bond it to a polar group-containing thermoplastic resin, as described later, without using a modified copolymer.

[0037] The thermoplastic elastomer composition of this embodiment contains a polypropylene resin (b) for moldability and hardness adjustment. However, when heat-bonding with a polar group-containing thermoplastic resin, as described later, the polypropylene resin (b) has low affinity with the polar group-containing thermoplastic resin composition, and the adhesive strength is almost nonexistent. The thermal adhesion of the thermoplastic elastomer composition of this embodiment tends to be controllable by the amount of vinyl aromatic monomer units and vinyl bonds in the hydrogenated block copolymers (a-1) and (a-2). The vinyl aromatic monomer content of the hydrogenated block copolymer (a-2) is 35% to 70% by mass (as per requirement (2-3) above), but for example, the higher the amount of styrene in the hydrogenated block copolymer, and the higher the content of component (a-2) in the thermoplastic elastomer composition of this embodiment, the greater the affinity with the polar group-containing thermoplastic resin described later, and the higher the adhesive strength tends to be. Furthermore, the hydrogenated block copolymer (a-2) has a pre-hydrogenation vinyl bond content of 60 mol% to 95 mol% in the conjugated diene monomer units in polymer block B2 (as per requirement (2-5) above). Within this range, the higher the vinyl bond content, and for the same vinyl bond content, the higher the proportion of component (a-2), the better the compatibility with the polypropylene resin (b) and the finer the dispersion. This compensates for the low affinity of the polypropylene resin (b) to polar group-containing thermoplastic resins, which is a drawback of the polypropylene resin (b). In other words, these synergistic effects improve the thermal adhesion between the polar group-containing thermoplastic resin and the thermoplastic elastomer composition of this embodiment.

[0038] The thermoplastic elastomer composition of this embodiment, from the viewpoint of improving the balance of mechanical strength, flexibility, resilience, moldability and heat adhesion, contains, in addition to the above-mentioned hydrogenated block copolymer (a-1) and hydrogenated block copolymer (a-2), one or more polypropylene resins (b) and non-aromatic softeners (c), and further, the content of the hydrogenated block copolymer (a-2) is 5 to 70% by mass of the total amount of the above components (a-1), (a-2), (b), and (c). The preferred lower limit is 10% by mass or more, and more preferably 15% by mass or more. The preferred upper limit is 65% by mass or less, and more preferably 60% by mass or less.

[0039] In the hydrogenated block copolymer (a-2), polymer block A2, which mainly consists of vinyl aromatic monomer units, has a content of vinyl aromatic monomer units of 50% by mass or more (as per requirement (2-2) above), and from the viewpoint of the thermal smability of the thermoplastic elastomer composition of this embodiment to the polar group-containing thermoplastic resin described later, it is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0040] In the hydrogenated block copolymer (a-2), polymer block B2 mainly consisting of conjugated diene monomer units means that the content of conjugated diene monomer units in polymer block B2 exceeds 50% by mass, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0041] The vinyl aromatic compounds used to form vinyl aromatic monomer units in polymer block A2 refer to compounds having a vinyl group and an aromatic ring. Examples of vinyl aromatic compounds, though not limited to those listed below, include styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N,N-dimethyl-p-aminoethylstyrene, and N,N-diethyl-p-aminoethylstyrene. Among these, styrene, α-methylstyrene, and divinylbenzene are preferred from the viewpoint of polymerizability. These vinyl aromatic compounds may be used individually or in combination of two or more.

[0042] The conjugated diene compound used to form the conjugated diene monomer unit in polymer block B2 is a diolefin having a pair of conjugated double bonds (two double bonds bonded in a conjugated manner). Examples of conjugated diene compounds include, but are not limited to, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, and 1,3-hexadiene. Among these, 1,3-butadiene and 2-methyl-1,3-butadiene (isoprene) are preferred from the viewpoint of polymerizability. These conjugated diene compounds may be used individually or in combination of two or more.

[0043] The hydrogenated block copolymer (a-2) has a structure that is not limited to the following, but for example, is represented by the following general formulas (85) to (14). Furthermore, the hydrogenated block copolymer (a-2) may be a mixture containing multiple types of structures represented by the following general formulas (8) to (14) in any proportion. (A2-B2) n (8) A2-(B2-A2) n (9) B2-(A2-B2) n (10) [(B2-A2) n ] m -Z (11) [(A2-B2) n ] m -Z (12) [(B2-A2) n -B2] m -Z (13) [(A2-B2) n -A2] m -Z (14)

[0044] In general formulas (8) to (14), A2 is a polymer block mainly composed of vinyl aromatic monomer units, and B2 is a polymer block mainly composed of conjugated diene monomer units. The boundary between polymer block A2 and polymer block B2 does not necessarily need to be clearly distinguishable. Furthermore, n is an integer greater than or equal to 1, preferably an integer between 1 and 5. m is an integer greater than or equal to 2, preferably between 2 and 11, more preferably between 2 and 8. Z represents a coupling agent residue. Here, a coupling agent residue refers to the residue after a coupling agent has been added to bond multiple copolymers of conjugated diene monomer units and vinyl aromatic monomer units between polymer blocks A2-A2, polymer blocks B2-B2, or polymer blocks A2-B2. The coupling agent is not limited to the following, but examples include silicon halide compounds and acid esters, which will be described later. The structural formula of the hydrogenated block copolymer (a-2) is preferably formula (8), (9), or (10), more preferably formula (8) or (10), and even more preferably formula (8).

[0045] In general formulas (8) to (14), the vinyl aromatic monomer units in polymer block A2 and polymer block B2 may be uniformly distributed or tapered. Furthermore, if polymer block A2 and polymer block B2 are copolymer blocks of vinyl aromatic monomer units and conjugated diene monomer units, there may be multiple portions in the copolymer block where the vinyl aromatic monomer units are uniformly distributed and / or tapered. Moreover, the copolymer block portion may contain multiple portions with different vinyl aromatic monomer unit content.

[0046] As described above, the content of total vinyl aromatic monomer units in the hydrogenated block copolymer (a-2) is 35% to 70% by mass (requirements (2-3) above). Preferably it is 37% to 70% by mass, more preferably 40% to 70% by mass, even more preferably more than 40% to 70% by mass, even more preferably more than 40% to 68% by mass, and even more preferably more than 40% to 66% by mass. When the total vinyl aromatic monomer unit content in the hydrogenated block copolymer (a-2) is 35% by mass or more, the mechanical strength and affinity of the thermoplastic elastomer composition of this embodiment with the polar group-containing thermoplastic resin described later tend to improve, and sufficient thermal adhesion strength is obtained. When the total vinyl aromatic monomer unit content in the hydrogenated block copolymer (a-2) is 70% by mass or less, the flexibility and resilience of the thermoplastic elastomer composition of this embodiment tend to improve further. The total vinyl aromatic monomer content in the hydrogenated block copolymer (a-2) can be controlled to the above numerical range by adjusting the amount of monomer added during the polymerization process of the hydrogenated block copolymer (a-2), and can be calculated using an ultraviolet spectrophotometer to determine the absorption intensity at a wavelength of 262 nm, as described in the examples below.

[0047] The weight-average molecular weight of the hydrogenated block copolymer (a-2) is 30,000 or more and less than 150,000 (as per requirement (2-4) above). When the weight-average molecular weight of the hydrogenated block copolymer (a-2) is 30,000 or more, the heat deformation resistance and recovery properties of the thermoplastic elastomer composition of this embodiment tend to improve. When the weight-average molecular weight of the hydrogenated block copolymer (a-2) is less than 150,000, the fluidity of the thermoplastic elastomer composition of this embodiment tends to improve, and the moldability and heat adhesion properties of the thermoplastic elastomer composition of this embodiment tend to improve. From a similar viewpoint, the weight-average molecular weight of the hydrogenated block copolymer (a-2) is preferably 40,000 to 130,000, and more preferably 50,000 to 110,000.

[0048] The molecular weight distribution (Mw / Mn) of the hydrogenated block copolymer (a-2) is preferably 1.01 to 8.0, more preferably 1.01 to 6.0, and even more preferably 1.01 to 5.0. If the molecular weight distribution of the hydrogenated block copolymer (a-2) is within the above range, the thermoplastic elastomer composition of this embodiment tends to exhibit better recovery properties. The Mw and Mn of the hydrogenated block copolymer (a-2) can be measured by GPC, specifically by the method described in the examples below.

[0049] The shape of the molecular weight distribution curve of the hydrogenated block copolymer (a-2) is not particularly limited; it may have a polymodal molecular weight distribution with two or more peaks, or a monomodal molecular weight distribution with one peak.

[0050] The hydrogenated block copolymer (a-2) has a pre-hydrogenation vinyl bond content of 60 mol% to 95 mol% in the conjugated diene monomer units in polymer block B2 (as per requirement (2-5) above). Preferably, it is 63 mol% to 90 mol%, and more preferably 65 mol% to 85 mol%. In the hydrogenated block copolymer (a-2), if the amount of vinyl bonds in the conjugated diene monomer units in polymer block B2 before hydrogenation is 60 mol% or more, the compatibility with the polypropylene resin (b) described later tends to improve, and the thermoplastic elastomer composition of this embodiment tends to have good thermal adhesion. Furthermore, because the hydrogenated block copolymer (a-2) has a relatively small molecular weight and a high vinyl bond amount of 60 mol% or more, the fluidity of the thermoplastic elastomer composition of this embodiment improves, resulting in good wettability that follows the fine irregularities of the adherend surface, and thus the thermoplastic elastomer composition of this embodiment tends to have good thermal adhesion. Furthermore, the amount of vinyl bonds in the conjugated diene monomer unit before hydrogenation is 95 mol% or less, which tends to ensure the mechanical strength of the thermoplastic elastomer composition of this embodiment. The amount of vinyl bonding in a conjugated diene monomer unit can be measured using nuclear magnetic resonance spectroscopy (NMR) analysis with a block copolymer, and specifically, it can be measured by the method described in the examples below. The amount of vinyl bonding can be controlled to the above-mentioned numerical range by adjusting the type and amount of adjusting agents, such as tertiary amines, which will be described later.

[0051] As described above, from the viewpoint of the thermal adhesion strength of the thermoplastic elastomer composition of this embodiment, and the flexibility and resilience of the thermoplastic elastomer composition, the hydrogenated block copolymer (a-2) shall have a total vinyl aromatic monomer unit content of 35% to 70% by mass (requirement (2-3) above), and from the viewpoint of the thermal adhesion and mechanical strength of the thermoplastic elastomer composition of this embodiment, the amount of vinyl bonds in the conjugated diene monomer units before hydrogenation shall be 60 mol% to 95 mol% (requirement (2-5) above).

[0052] The hydrogenation rate of the double bonds of the conjugated diene monomer units in the hydrogenated block copolymer (a-2) shall be 50 mol% or more (as per requirement (2-6) above), preferably 80% or more, and more preferably 90% or more. If the hydrogenation rate of the double bonds of the conjugated diene monomer units in the hydrogenated block copolymer (a-2) is 50 mol% or more, the deterioration of the thermoplastic elastomer composition of this embodiment due to thermal degradation, i.e., oxidative degradation, can be suppressed. There is no particular upper limit to the above hydrogenation rate, but it is preferably 100% or less, and preferably 99% or less. The hydrogenation rate of the double bonds of the conjugated diene monomer units in the hydrogenated block copolymer (a-2) can be controlled within the above numerical range by adjusting the type and amount of hydrogenation catalyst used and the hydrogenation conditions, and can be measured by the method described in the examples below.

[0053] The hydrogenation rate of aromatic double bonds based on vinyl aromatic monomer units in the hydrogenated block copolymer (a-2) is not particularly limited, but is preferably 50% or less, more preferably 30% or less, and even more preferably 20% or less.

[0054] When the hydrogenated block copolymer (a-2) has at least two polymer blocks A2 and at least two polymer blocks B2, at least one polymer block B2 is located at the end of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the end is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 3% by mass or more in the hydrogenated block copolymer (a-2). The upper limit is preferably 10% by mass or less, more preferably 9% by mass or less, and even more preferably 8% by mass or less. Furthermore, in such cases, it is preferable that the hydrogenated block copolymer (a-2) does not have a peak with a weight-average molecular weight of 250,000 or more. Furthermore, in such a configuration, it is preferable that the hydrogenated block copolymer (a-2) contains more than 40% by mass and 70% by mass or less of total vinyl aromatic monomer units. At least one polymer block B2 is located at the end of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the end is within the above numerical range, which tends to result in a thermoplastic elastomer composition of this embodiment exhibiting superior flexibility and fluidity. The content of the polymer block B2 at the end can be calculated by dividing the mass of the conjugated diene polymerized at the end by the mass of the total monomer used in the polymerization reaction. In the above configuration, the hydrogenated block copolymer (a-2) does not have a peak with a weight-average molecular weight of 250,000 or more, which improves the fluidity of the thermoplastic elastomer composition of this embodiment, resulting in good wettability to the adherend surface and a tendency for good thermal adhesion of the thermoplastic elastomer composition of this embodiment. Furthermore, in this configuration, the content of total vinyl aromatic monomer units in the hydrogenated block copolymer (a-2) is more than 40% by mass and 70% by mass or less, which tends to result in a good balance between the mechanical strength, thermal adhesion strength with polar group-containing thermoplastic resins, flexibility, and resilience of the thermoplastic elastomer composition of this embodiment. In order to ensure that the hydrogenated block copolymer (a-2) has at least one polymer block B2 at its terminal, that the content of the polymer block B2 at that terminal is within the above numerical range, and that it does not have a peak with a weight-average molecular weight of 250,000 or more, and furthermore, that the content of all vinyl aromatic monomer units in the hydrogenated block copolymer (a-2) is within the above numerical range, it is effective to adjust the timing and amount of monomer addition in the polymerization process of the hydrogenated block copolymer (a-2).

[0055] (Method for producing hydrogenated block copolymer) The methods for producing the hydrogenated block copolymers (a-1) and (a-2) are not limited to the following, but include, for example, the methods described in Japanese Patent Publication No. 36-19286, Japanese Patent Publication No. 43-17979, Japanese Patent Publication No. 46-32415, Japanese Patent Publication No. 49-36957, Japanese Patent Publication No. 48-2423, Japanese Patent Publication No. 48-4106, Japanese Patent Publication No. 51-49567, Japanese Patent Publication No. 59-166518, etc.

[0056] The hydrogenated block copolymers (a-1) and (a-2), which include conjugated diene monomer units and vinyl aromatic monomer units before hydrogenation, are not limited to the following but can be obtained, for example, by anionic living polymerization using a polymerization initiator such as an organoalkali metal compound in a hydrocarbon solvent. The hydrocarbon solvent is not particularly limited and includes, for example, aliphatic hydrocarbons such as n-butane, isobutane, n-pentane, n-hexane, n-heptane, and n-octane; alicyclic hydrocarbons such as cyclohexane, cycloheptane, and methylcycloheptane; and aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene.

[0057] While there are no particular limitations on the polymerization initiator, organoalkali metal compounds that are generally known to have anionic polymerization activity with respect to conjugated diene compounds and vinyl aromatic compounds can be used. Examples of such organoalkali metal compounds, though not limited to the above, include aliphatic hydrocarbon alkali metal compounds having 1 to 20 carbon atoms, aromatic hydrocarbon alkali metal compounds having 1 to 20 carbon atoms, and organoaminoalkali metal compounds having 1 to 20 carbon atoms. The alkali metals included in the polymerization initiator are not limited to those listed below, but examples include lithium, sodium, potassium, etc. Note that one or more alkali metals may be present in a single molecule. Examples of polymerization initiators include n-propyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, n-pentyllithium, n-hexyllithium, benzyllithium, phenyllithium, tolyllithium, reaction products of diisopropenylbenzene and sec-butyllithium, and reaction products of divinylbenzene, sec-butyllithium and a small amount of 1,3-butadiene. Furthermore, lithium compounds containing 1-(t-butoxy)propyllithium and a few isoprene monomers inserted therein to improve solubility, as disclosed in U.S. Patent No. 5,708,092, siloxy group-containing alkyllithiums such as 1-(t-butyldimethylsiloxy)hexyllithium disclosed in British Patent No. 2,241,239, amino group-containing alkyllithiums disclosed in U.S. Patent No. 5,527,753, diisopropylamide lithium, and hexamethyldisilazidolithium, among other aminolithium compounds, can also be used as polymerization initiators.

[0058] When copolymerizing a conjugated diene compound and a vinyl aromatic compound using an organoalkali metal compound as a polymerization initiator, tertiary amine compounds, ether compounds, and metal alkoxide compounds can be added as modifiers to adjust the content of vinyl bonds (1,2- or 3,4- bonds) originating from the conjugated diene compound incorporated into the copolymer, and to adjust the random copolymerization properties between the conjugated diene compound and the vinyl aromatic compound. Adjusting agents may be used individually or in combination of two or more.

[0059] As the tertiary amine compound used as the adjusting agent, a compound represented by the general formula R1R2R3N can be used. Here, in the general formula, R1, R2, and R3 represent hydrocarbon groups having 1 to 20 carbon atoms or hydrocarbon groups having a tertiary amino group. Examples of tertiary amine compounds include, but are not limited to, trimethylamine, triethylamine, tributylamine, N,N-dimethylaniline, N-ethylpiperidine, N-methylpyrrolidine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetraethylethylenediamine, 1,2-dipiperidinoethane, trimethylaminoethylpiperazine, N,N,N',N”,N”-pentamethylethylenetriamine, and N,N'-dioctyl-p-phenylenediamine.

[0060] As the adjusting agent, linear ether compounds and cyclic ether compounds can be used. Examples of linear ether compounds include, but are not limited to, dimethyl ether, diethyl ether, diphenyl ether, ethylene glycol diethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, and other ethylene glycol dialkyl ether compounds, as well as diethylene glycol dialkyl ether compounds, such as diethylene glycol diethyl ether, diethylene glycol dibutyl ether, and other diethylene glycol dialkyl ether compounds. Examples of cyclic ether compounds include, but are not limited to, tetrahydrofuran, dioxane, 2,5-dimethyloxolane, 2,2,5,5-tetramethyloxolane, 2,2-bis(2-oxolanyl)propane, and alkyl ethers of furfuryl alcohol.

[0061] Examples of metal alkoxide compounds used as modifiers include, but are not limited to, sodium t-pentoxide, sodium t-butoxide, potassium t-pentoxide, potassium t-butoxide, and the like.

[0062] The copolymerization method for conjugated diene compounds and vinyl aromatic compounds using an organoalkali metal compound as a polymerization initiator is not particularly limited and may be batch polymerization, continuous polymerization, or a combination thereof. From the viewpoint of adjusting the molecular weight distribution to a desirable and appropriate range, a batch polymerization method is preferred. The polymerization temperature is not particularly limited, but is usually 0 to 180°C, and preferably 30 to 150°C. The time required for polymerization varies depending on the conditions, but is usually within 48 hours, preferably 0.1 to 10 hours. Furthermore, polymerization is preferably carried out under an inert gas atmosphere such as nitrogen gas. The polymerization pressure is not particularly limited and should be within a range sufficient to maintain the monomer and solvent in the liquid phase within the polymerization temperature range mentioned above.

[0063] Furthermore, a coupling reaction may be carried out by adding the necessary amount of a coupling agent with two or more functional groups at the end of polymerization. The coupling agent with two or more functional groups is not particularly limited, and known ones can be used. Examples of difunctional coupling agents include, but are not limited to, alkylalkoxysilanes such as dimethyldimethoxysilane and dimethyldiethoxysilane, silicon halide compounds such as dimethyldichlorosilane and dimethyldibromosilane; and acid esters such as methyl benzoate, ethyl benzoate, phenyl benzoate, and phthalates. Furthermore, if the hydrogenated block copolymers (a-1) and (a-2) are obtained by coupling reaction using these coupling agents, this does not violate the non-denaturation requirement.

[0064] Polyfunctional coupling agents with three or more functional groups are not limited to the following, but include, for example, polyalcohols with three or more valent groups, polyvalent epoxy compounds such as epoxidized soybean oil and diglycidylbisphenol A, alkylalkoxysilanes such as methyltrimethoxysilane, tetramethoxysilane, methyltriethoxysilane, and tetraethoxysilane, and those with the general formula R 1 (4-n) SiX n Examples of silicon halide compounds represented by [formula] include [formula]. Here, in the general formula, R 1 represents a hydrocarbon group with 1 to 20 carbon atoms, X represents a halogen, and n represents an integer of 3 or 4.

[0065] Examples of silicon halide compounds include, but are not limited to, methylsilyl trichloride, t-butylsilyl trichloride, silicon tetrachloride, and their brominated products.

[0066] The hydrogenation catalyst used to produce the hydrogenated block copolymer is not particularly limited, and for example, hydrogenation catalysts described in Japanese Patent Publication No. 42-8704, Japanese Patent Publication No. 43-6636, Japanese Patent Publication No. 63-4841, Japanese Patent Publication No. 1-37970, Japanese Patent Publication No. 1-53851, Japanese Patent Publication No. 2-9041, etc., can be used. Preferred hydrogenation catalysts include titanocene compounds and mixtures of the titanocene compound with a reducing organometallic compound. The titanocene compounds are not particularly limited, but examples include the compounds described in Japanese Patent Publication No. 8-109219. Specifically, examples include compounds having at least one ligand having a substituted or unsubstituted cyclopentadienyl structure, an indenyl structure, and a fluorenyl structure, such as biscyclopentadienyl titanium dichloride and monopentamethylcyclopentadienyl titanium trichloride. Reducing organometallic compounds include, but are not limited to, organolithium and other organoalkali metal compounds, organomagnesium compounds, organoaluminum compounds, organoboron compounds, organozinc compounds, and the like.

[0067] The reaction temperature for hydrogenation is typically 0 to 200°C, preferably 30 to 150°C. The pressure of the hydrogen used in the hydrogenation reaction is preferably 0.1 to 15 MPa, more preferably 0.2 to 10 MPa, and even more preferably 0.3 to 5 MPa. The reaction time for hydrogenation is usually 3 minutes to 10 hours, preferably 10 minutes to 5 hours. Furthermore, the hydrogenation reaction can be carried out using a batch process, a continuous process, or a combination of both.

[0068] After the hydrogenation reaction is complete, catalyst residue may be removed from the reaction solution as needed. Methods for separating the hydrogenated block copolymer from the solvent include, but are not limited to, adding a polar solvent that is a poor solvent for the hydrogenated block copolymer, such as acetone or alcohol, to a solution of the hydrogenated block copolymer to precipitate and recover the hydrogenated block copolymer; adding a solution of the hydrogenated block copolymer to hot water under stirring and removing the solvent by steam stripping; or directly heating a solution of the hydrogenated block copolymer to remove the solvent by distillation.

[0069] An antioxidant may be added to the reaction solution used to produce the hydrogenated block copolymer (a). Antioxidants include, but are not limited to, phenolic antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, amine-based antioxidants, and the like. Specifically, 2,6-di-t-butyl-4-methylphenol, n-octadecyl-3-(4'-hydroxy-3',5'-di-t-butylphenyl)propionate, tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane], tris-(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate, 4,4'-butylidene-bis-(3-methyl-6-t-butylphenol), 3,9-bis[2-{3-(3-t-butyl-4-hydroxy-5-methyl Phenyl)propionyloxy}-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane, triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylanilino)1,3,5-triazine, pentaerythrityl-tetrakis[3 -(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxyhydrocinnamamide), 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, bis(3,5-di-t-butyl-4 -Hydroxybenzylphosphonate ethyl) calcium and polyethylene wax (50%) mixture, octylated diphenylamine, 2,4-bis[(octylthio)methyl]-o-cresol, isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, butyrate, 3,3-bis(3-t-butyl-4-hydroxyphenyl)ethylene ester, 1,1,3-tris-(2-methyl-4-hydroxy-5-t-butylphenyl)butane, 1,3,5-tris(4-t-butyl-3-hydroxy-2,Examples include 6-dimethylbenzyl isocyanurate, 2-t-butyl-6-(3'-t-butyl-5'-methyl-2'-hydroxybenzyl)-4-methylphenyl acrylate, and 2-[1-(2-hydroxy-3,5-di-t-pentylphenyl)-ethyl]-4,6-di-t-pentylphenyl acrylate.

[0070] (Polypropylene resin (b)) The thermoplastic elastomer composition of this embodiment contains a polypropylene resin (b). The polypropylene resin (b) is not limited to the following, but examples include propylene homopolymers, block copolymers or random copolymers of propylene and an olefin other than propylene, preferably an α-olefin having 2 to 20 carbon atoms, or blends thereof. Examples of α-olefins having 2 to 20 carbon atoms include, but are not limited to, ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, and the like. Preferably, the α-olefin has 2 to 8 carbon atoms, and more preferably, ethylene, 1-butene, 1-hexene, or 4-methyl-1-pentene. The polypropylene resin (b) may be used alone or in combination of two or more types.

[0071] The polypropylene resin (b) preferably has a melt flow rate (MFR) of 0.1 to 50 g / 10 min, determined under conditions of a temperature of 230°C and a load of 2.16 kg. The lower limit is more preferably 0.5 g / 10 min or more, and even more preferably 1.0 g / 10 min or more. The upper limit is more preferably 45 g / 10 min or less, and even more preferably 40 g / 10 min or less. If the MFR of the polypropylene resin (b) is within the above range, the moldability of the thermoplastic elastomer composition of this embodiment tends to improve further.

[0072] The method for producing polypropylene resin (b) is not limited to the following, but includes, for example, a method in which the above-mentioned monomer is polymerized using a Ziegler-Natta type catalyst that combines a titanium-containing solid transition metal component and an organometallic component. Examples of transition metal components used in Ziegler-Natta type catalysts include, but are not limited to, solid components having titanium, magnesium, and halogens as essential components and electron-donating compounds as optional components, or titanium trichloride. Examples of organometallic components include, but are not limited to, aluminum compounds.

[0073] Furthermore, the polymerization method used to produce the polypropylene resin (b) is not limited to the following, but examples include slurry polymerization, gas-phase polymerization, bulk polymerization, solution polymerization, or multi-stage polymerization combining these methods. In these polymerization methods, when obtaining a propylene homopolymer, only propylene is polymerized, and when obtaining a copolymer, propylene and monomers other than propylene are polymerized.

[0074] In the thermoplastic elastomer composition of this embodiment, the content of polypropylene resin (b) is 10 parts by mass or more, preferably 20 parts by mass or more, and more preferably 30 parts by mass or more, per 100 parts by mass of the hydrogenated block copolymer (a-1). The upper limit is 100 parts by mass, preferably 90 parts by mass or less, and more preferably 80 parts by mass or less. When the content of polypropylene resin (b) is 10 parts by mass or more, good fluidity and excellent moldability are obtained in the thermoplastic elastomer composition of this embodiment. When the content of polypropylene resin (b) is 100 parts by mass or less, good rebound elasticity and flexibility can be obtained in the thermoplastic elastomer composition of this embodiment.

[0075] (Non-aromatic softeners (c)) The thermoplastic elastomer composition of this embodiment contains a non-aromatic softener (c). The non-aromatic softener (c) is not particularly limited as long as it does not exhibit aromaticity and can soften the thermoplastic elastomer composition of this embodiment; known non-aromatic softeners can be used. The non-aromatic softener (c) is not limited to the following, but examples include paraffinic oils, naphthenic oils, paraffin waxes, liquid paraffin, white mineral oil, and plant-based softeners. Among these, paraffinic oils, liquid paraffin, and white mineral oil are preferred from the viewpoint of low-temperature properties, elution resistance, and hygiene of the molded article containing the thermoplastic elastomer composition of this embodiment.

[0076] The kinematic viscosity of the non-aromatic softener (c) at 40°C is preferably 10 to 500 mm². 2 It is per second. The kinematic viscosity of the non-aromatic softener (c) at 40°C is 10 mm². 2 If the temperature is 2 / second or higher, the heat deformation resistance and softener retention of the thermoplastic elastomer composition of this embodiment tend to improve further. The kinematic viscosity of the non-aromatic softener (c) at 40°C is 500 mm². 2 If the value is less than / second, the fluidity of the thermoplastic elastomer composition of this embodiment tends to improve further, and its moldability tends to improve further. The kinematic viscosity of the non-aromatic softener (c) can be measured using a glass capillary viscometer.

[0077] In the thermoplastic elastomer composition of this embodiment, the content of the non-aromatic softener (c) is 50 to 300 parts by mass, preferably 60 parts by mass or more, and more preferably 70 parts by mass or more, per 100 parts by mass of the hydrogenated block copolymer (a-1). The upper limit is 300 parts by mass or less, preferably 250 parts by mass or less, and more preferably 200 parts by mass or less. If the content of the non-aromatic softener (d) is within the above range, the retention of the non-aromatic softener (c), i.e., the effect of suppressing bleed-out, can be further improved, and a thermoplastic elastomer composition with superior moldability, flexibility, and recovery properties tends to be obtained.

[0078] (Inorganic filler (d)) The thermoplastic elastomer composition of this embodiment may contain an inorganic filler (d) from the viewpoint of adjusting the molded appearance, surface texture, feel, and gloss.

[0079] Examples of inorganic fillers (d) include, but are not limited to, talc, calcium carbonate, calcium oxide, zinc carbonate, wollastonite, zeolite, wollastonite, silica, alumina, clay, titanium dioxide, magnesium hydroxide, magnesium oxide, sodium silicate, calcium silicate, magnesium silicate, sodium aluminate, calcium aluminate, sodium aluminosilicate, zinc oxide, potassium titanate, hydrotalcite, barium sulfate, titanium black, etc., as well as carbon blacks such as furnace black, thermal black, and acetylene black. These inorganic fillers may be used individually or in combination of two or more types. Furthermore, these inorganic fillers may be surface-treated to improve their dispersibility in the thermoplastic elastomer composition of this embodiment. Examples of surface treatment agents include fatty acids, resin acids, oils and fats, surfactants, and coupling agents (silane-based, titanium-based, phosphoric acid-based, carboxylic acid-based, etc.), but are not limited to these as long as they can act on the surface of the inorganic filler.

[0080] (Organic peroxide(e)) The thermoplastic elastomer composition of this embodiment may be partially crosslinked in the presence of organic peroxide(e) from the viewpoint of heat deformation resistance and recovery properties. Organic peroxides (e) are not limited to the following, but include, for example, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, dicumyl peroxide, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-butylperoxybenzoate, t-butylcumyl peroxide, diisopropylbenzene hydroxyperoxide, 1,3-bis(t-butylperoxyisopropyl)benzene, benzoyl peroxide, and 1,1-di(t-butylperoxy)-3,3,5-trimethylcyclohexyl peroxide. Examples include t-butyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, di-t-butyl peroxide, 1,1-di-t-butylperoxycyclohexane, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyn-3, n-butyl-4,4-bis(t-butylperoxy)valerate, t-butylperoxyisobutyrate, t-butylperoxy-2-ethylhexanoate, and t-butylperoxyisopropylcarbonate. These may be used individually or in combination of two or more organic peroxides. The amount of organic peroxide (e) used is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 4 parts by mass, and even more preferably 0.3 to 3 parts by mass, per 100 parts by mass of hydrogenated block copolymer (a-1). If the amount of organic peroxide (e) used is within the aforementioned range, a thermoplastic elastomer composition with superior heat deformation resistance and recovery properties tends to be obtained without reducing processability.

[0081] (Crosslinking agent (f)) Furthermore, when partially crosslinking the thermoplastic elastomer composition of this embodiment, a crosslinking aid can be used as needed to adjust the degree of crosslinking. Examples of crosslinking aids (f) include, but are not limited to, trimethylolpropane triacrylate, triallyl isocyanurate, triallyl cyanurate, triallyl formal, triallyl trimellitate, N,N'-m-phenylene bismaleimide, dipropagyl terephthalate, diallyl phthalate, tetraallyl terephthalamide, triallyl phosphate, divinylbenzene, ethylene dimethacrylate, diallyl phthalate, quinone dioxime, ethylene glycol dimethacrylate, polyfunctional methacrylate monomers, polyhydric alcohol methacrylates and acrylates, and unsaturated silane compounds (e.g., vinyltrimethoxysilane, vinyltriethoxysilane, etc.). These can be used individually or in combination of two or more as needed. The amount of crosslinking aid (f) used is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, and even more preferably 0.5 parts by mass or more, per 100 parts by mass of hydrogenated block copolymer (a-1). The preferred upper limit is 10 parts by mass or less, more preferably 8 parts by mass or less, and even more preferably 7 parts by mass or less.

[0082] (Other ingredients) The thermoplastic elastomer composition of this embodiment may contain other additives in addition to the components (a) to (f) described above, as long as the purpose of this embodiment is not impaired. Other additives include heat stabilizers, antioxidants, ultraviolet absorbers, anti-aging agents, plasticizers, light stabilizers, crystal nucleating agents, impact modifiers, pigments, lubricants, antistatic agents, flame retardants, flame retardant aids, compatibilizers, and tackifiers. In particular, adding silicone oil as a lubricant improves sliding properties, which is effective in reducing needle-piercing resistance and improving coring. Examples of silicone oils include common dimethylpolysiloxane and phenylmethylpolysiloxane, with dimethylpolysiloxane being particularly preferred. The amount of silicone oil to be added is preferably 0.5 parts by mass or more, more preferably 0.7 parts by mass or more, and even more preferably 1.0 part by mass or more, per 100 parts by mass of hydrogenated block copolymer (a-1). The upper limit is preferably 10 parts by mass or less, more preferably 7 parts by mass or less, and even more preferably 5 parts by mass or less. There are no particular restrictions on the kinematic viscosity of the silicone oil, but 10 to 10,000 mm is recommended. 2 A speed of 50-7000mm / second is preferred. 2 / second is more preferable, 100-5000mm 2 / second is even more preferable. The aforementioned other additives may be used individually or in combination of two or more.

[0083] (Method for producing thermoplastic elastomer compositions) The thermoplastic elastomer composition of this embodiment and the method for producing a molded article (e.g., pellets) made from the thermoplastic elastomer composition are not particularly limited, and conventionally known methods can be applied. Examples include melt-kneading methods using common mixers such as pressure kneaders, Banbury mixers, internal mixers, Laboplast mills, Mixlabs, single-screw extruders, twin-screw extruders, Conkneaders, and multi-screw extruders, as well as methods in which each component is dissolved or dispersed and mixed, and then the solvent is removed by heating.

[0084] When partially crosslinking the thermoplastic elastomer composition of this embodiment with the organic peroxide (e) described above, the compounding of each component (a) to (d) and partial crosslinking with the organic peroxide (e) and, if necessary, the added crosslinking aid (f) may be performed simultaneously, or the organic peroxide (e) and, if necessary, the crosslinking aid (f) may be added after the compounding of components (a) to (d) to perform partial crosslinking. Alternatively, some of components (a) to (d) may be mixed with an organic peroxide (e) and, if necessary, a crosslinking aid (f), and after crosslinking, other components may be mixed in. Partial crosslinking can be carried out under temperature conditions where the decomposition of the organic peroxide(e) used occurs, generally between 150 and 250°C. When compounding some or all of components (a) to (d) and crosslinking with an organic peroxide (e) and a crosslinking aid (f) added as needed is performed simultaneously, compounding can be carried out by using the melt kneader at a temperature at which the decomposition of the organic peroxide (e) occurs.

[0085] [Multilayer molded body] The multilayer molded article of this embodiment has a thermoplastic elastomer composition layer and a polar group-containing thermoplastic resin layer.

[0086] The multilayer molded article of this embodiment is a multilayer molded article having a polar group-containing thermoplastic resin layer and a thermoplastic elastomer composition layer containing a hydrogenated block copolymer (a), a polypropylene resin (b), and a non-aromatic softener (c), wherein the thermoplastic elastomer composition layer is provided in contact with the polar group-containing thermoplastic resin layer.

[0087] The hydrogenated block copolymer (a) is an unmodified block copolymer that does not contain a modifying group. Because the hydrogenated block copolymer (a) is unmodified, a thermoplastic elastomer composition can be obtained that is free from odor, discoloration, and impurities from unreacted materials. Furthermore, "unmodified" means that the hydrogenated block copolymer (a) does not contain modified groups formed by a specified modifying agent. Examples of modified groups include amino groups containing a nitrogen atom, nitro groups, amide bonds, azo bonds, ketone groups in which an oxygen atom is bonded to a carbon atom by a double bond, carbonyl groups, carboxyl groups, aldehyde groups, hydroxyl groups in which an oxygen atom and a hydrogen atom are bonded, sulfo groups containing a sulfur atom, and compound groups in which halogen elements such as fluorine, chlorine, or brown atoms are bonded. If the hydrogenated block copolymer (a) is obtained by a coupling reaction with a coupling agent at the end of the polymerization reaction, and has a Si atom derived from the coupling agent and an O atom adjacent to it and bonded in a linear chain as residues, then it shall satisfy the requirement of being "undenatured".

[0088] The hydrogenated block copolymer (a) is a hydrogenated block copolymer which is a hydrogenated product of a block copolymer having vinyl aromatic monomer units and conjugated diene monomer units, and has one or more molecular weight peaks (weight-based molecular weight; PMw) measured by GPC between 30,000 and less than 150,000. Preferably, it has one or more molecular weight peaks between 40,000 and 130,000, and more preferably between 50,000 and 110,000. When the molecular weight peak of the hydrogenated block copolymer (a) is 30,000 or higher, the heat deformation resistance and recovery properties of the thermoplastic elastomer composition of this embodiment tend to improve. Furthermore, when the molecular weight peak is less than 150,000, the fluidity of the thermoplastic elastomer composition of this embodiment tends to improve, and the moldability and heat adhesion properties of the thermoplastic elastomer composition of this embodiment tend to improve. Furthermore, the PMw of the hydrogenated block copolymer can be measured by GPC, specifically by the method described in the examples below.

[0089] The hydrogenated block copolymer having a molecular weight peak of 30,000 to less than 150,000 according to the GPC has a total vinyl aromatic monomer unit content of 35% by mass or more, preferably 37% by mass or more, more preferably 40% by mass or more, and even more preferably more than 40% by mass and 66% by mass or less. The upper limit is 70% by mass or less, preferably 68% by mass or less, and more preferably 66% by mass or less. When the content of total vinyl aromatic monomer units in the hydrogenated block copolymer, whose molecular weight peak according to the GPC is between 30,000 and less than 150,000, is 35% by mass or more, the mechanical strength and affinity of the thermoplastic elastomer composition of this embodiment with polar group-containing thermoplastic resins tend to improve, and sufficient thermal adhesion strength tends to be obtained. When the content of total vinyl aromatic monomer units is 70% by mass or less, the flexibility and resilience of the thermoplastic elastomer composition of this embodiment tend to improve further. The total content of vinyl aromatic monomer units can be controlled to the above-mentioned range by adjusting the amount of monomer added during the polymerization process of the hydrogenated block copolymer, and can be calculated using an ultraviolet spectrophotometer based on the absorption intensity at 262 nm as described in the examples described later.

[0090] The amount of vinyl bonds in the conjugated diene monomer units of the hydrogenated block copolymer, whose molecular weight peak according to the GPC is between 30,000 and less than 150,000, before hydrogenation is 60 mol% or more, preferably 63 mol% or more, and more preferably 65 mol% or more. The upper limit is 95 mol% or less, preferably 90 mol% or less, and more preferably 85 mol% or less. When the amount of vinyl bonds in the conjugated diene monomer units of the hydrogenated block copolymer, whose molecular weight peak according to the GPC is between 30,000 and less than 150,000, is 60 mol% or more before hydrogenation, the compatibility with polypropylene resin (b) tends to improve, and the thermoplastic elastomer composition of this embodiment tends to have good thermal adhesion. Furthermore, the fluidity also improves, and the wettability that follows the fine irregularities on the surface of the adherend becomes good, and the thermoplastic elastomer composition of this embodiment tends to have good thermal adhesion. Furthermore, if the amount of vinyl bonds in the conjugated diene monomer units of the hydrogenated block copolymer, whose molecular weight peak according to GPC is between 30,000 and less than 150,000, is 95 mol% or less before hydrogenation, then the thermoplastic elastomer composition of this embodiment tends to be able to ensure sufficient mechanical strength. The amount of vinyl bonded to a conjugated diene monomer unit can be measured using nuclear magnetic resonance spectroscopy (NMR) analysis with a block copolymer, specifically by the method described in the examples below. Furthermore, the amount of vinyl bonded can be controlled to the above-mentioned numerical range by adjusting the type and amount of modifiers such as tertiary amines, as described below.

[0091] The hydrogenated block copolymer (a) constituting the thermoplastic elastomer composition is, as described above, a hydrogenated polymer of a block copolymer having vinyl aromatic monomer units and conjugated diene monomer units. The hydrogenated block copolymer (a) has one or more molecular weight peaks (weight-based molecular weight; PMw) measured by GPC between 150,000 and 550,000. The molecular weight at which the peaks are present is preferably 170,000 or more, more preferably 190,000 or more, and even more preferably 210,000 or more. It is also preferably 500,000 or less, more preferably 450,000 or less, even more preferably 400,000 or less, even more preferably 350,000 or less, and even more preferably 300,000 or less. When the peak molecular weight of the hydrogenated block copolymer is 150,000 or higher, the thermoplastic elastomer composition of this embodiment tends to have good heat deformation resistance and recovery properties. When the peak molecular weight of the hydrogenated block copolymer is 550,000 or lower, the thermoplastic elastomer composition exhibits good fluidity, and therefore tends to have sufficient moldability. Furthermore, the PMw of the hydrogenated block copolymer can be measured by GPC, specifically by the method described in the examples below.

[0092] The content of total vinyl aromatic monomer units in the hydrogenated block copolymer with a molecular weight peak of 150,000 to 550,000 according to the GPC is 15% to less than 35% by mass, preferably 17% by mass or more, more preferably 19% by mass or more, even more preferably 21% by mass or more, and even more preferably 23% by mass or more. Furthermore, it is preferably 34% by mass or less, and more preferably 33% by mass or less. When the content of total vinyl aromatic monomer units in the hydrogenated block copolymer with a molecular weight peak of 150,000 to 550,000 according to the GPC is 15% by mass or more, the mechanical strength and heat deformation resistance of the thermoplastic elastomer composition of this embodiment tend to improve. When the content of total vinyl aromatic monomer units in the hydrogenated block copolymer with a molecular weight peak of 150,000 to 550,000 according to the GPC is less than 35% by mass, the flexibility, resilience, and rebound elasticity of the thermoplastic elastomer composition of this embodiment tend to improve. The total content of vinyl aromatic monomer units can be controlled to the above numerical range by adjusting the amount of monomer added during the polymerization process of the hydrogenated block copolymer, and can be calculated using an ultraviolet spectrophotometer to determine the absorption intensity at a wavelength of 262 nm, as described in the examples below.

[0093] The hydrogenation rate of the aliphatic double bonds derived from the conjugated diene compound in the hydrogenated block copolymer with a molecular weight peak of 150,000 to 550,000 according to the GPC, i.e., the double bonds of the conjugated diene monomer unit, is 50 mol% or more, preferably 60 mol% or more, and more preferably 70 mol% or more. A hydrogenation rate of 50 mol% or more tends to more effectively suppress the deterioration of mechanical properties due to thermal degradation (oxidative degradation). Furthermore, a hydrogenation rate of 70 mol% or more tends to yield better weather resistance. The upper limit of the hydrogenation rate is not particularly limited, but it is preferably 100% or less, and more preferably 99% or less. The hydrogenation rate of the double bonds of the conjugated diene monomer units of the hydrogenated block copolymer with a molecular weight peak of 150,000 to 550,000 as measured by the aforementioned GPC can be controlled to the above numerical range by adjusting the type and amount of hydrogenation catalyst used and the hydrogenation conditions, and can be measured by the method described in the examples below.

[0094] The multilayer molded article of this embodiment preferably has a configuration in which the thermoplastic elastomer composition layer and the polar group-containing thermoplastic resin composition layer are heat-fused together. In other words, the thermoplastic elastomer composition of this embodiment constitutes a thermoplastic elastomer composition layer that is heat-fused to the polar group-containing thermoplastic resin composition layer constituting the multilayer molded body.

[0095] The multilayer molded body of this embodiment described above preferably has the following configuration. In other words, the multilayer molded body of this embodiment is composed of hydrogenated block copolymer (a-1) and hydrogenated block copolymer (a-2), The above (a-1) satisfies the requirements of (1-1) to (1-4) below, The above (a-2) satisfies the requirements of (2-1) to (2-6) below, Preferably, the thermoplastic elastomer composition layer contains 100 parts by mass of (a-1), 10 to 100 parts by mass of (b), and 50 to 300 parts by mass of (c), and the content of (a-2) in the thermoplastic elastomer composition layer is 5 to 70% by mass of the total amount of components (a-1), (a-2), (b), and (c), and is a multilayer molded article. (1-1): Contains polymer block A1 mainly composed of one or more vinyl aromatic monomer units and polymer block B1 mainly composed of one or more conjugated diene monomer units. (1-2): The total content of vinyl aromatic monomer units is 15% by mass or more and less than 35% by mass. (1-3): The weight-average molecular weight is between 150,000 and 550,000. (1-4): More than 50 mol% of the double bonds in the conjugated diene monomer units are hydrogenated. (2-1): Contains polymer block A2 mainly composed of one or more vinyl aromatic monomer units and polymer block B2 mainly composed of one or more conjugated diene monomer units. (2-2): The content of vinyl aromatic monomer units in polymer block A2 is 50% by mass or more. (2-3): The total content of vinyl aromatic monomer units is 35% to 70% by mass. (2-4): The weight-average molecular weight is 30,000 or more and less than 150,000. (2-5): The amount of vinyl bonds in the conjugated diene monomer units in polymer block B2 before hydrogenation is 60 mol% to 95 mol%. (2-6): More than 50 mol% of the double bonds in the conjugated diene monomer units are hydrogenated. By having the above configuration, a multilayer molded article can be obtained that has practically good odor and color, and excellent moldability, heat bonding strength, recovery, and mechanical strength.

[0096] In addition, in the multilayer laminate of this embodiment, the preferred forms of the hydrogenated block copolymers (a-1) and (a-2) are the same as those of the thermoplastic elastomer composition of this embodiment.

[0097] (Thermoplastic resin containing polar groups) As described above, the multilayer laminate in this actual form has a polar group-containing thermoplastic resin layer. The polar group-containing thermoplastic resin that constitutes the polar group-containing thermoplastic resin layer contains one or more polar groups within its molecule. Examples of thermoplastic resins containing polar groups include, but are not limited to, polyamide resins, polyphenylene sulfide resins, polyester resins, polycarbonate resins, acrylonitrile-butadiene-styrene copolymer (ABS) resins (hereinafter also simply referred to as "ABS"), acrylic resins, and polyacetal resins. These may be used individually or as a mixture of two or more.

[0098] Polyamide resins have amino groups, carboxyl groups, and amide groups in their main chain. Polyphenylene sulfide resins have carboxylic acids at the polymer chain ends. Polyester resins have an ester structure in their main chain and hydroxyl or carboxyl groups at their ends. Polycarbonate resin has carbonate esters in its main chain and hydroxyl groups at its terminals. ABS resin contains nitrile groups. Acrylic resins are a general term for polyacrylic acid, polyacrylic acid esters, polymethacrylic acid, and polymethacrylic acid esters, and have carboxyl groups and / or ester groups. Polyacetal resin has an ether structure.

[0099] (Application) The multilayer molded body of this embodiment can be suitably used in applications such as sealing members requiring flexibility and resilience in home appliance parts, industrial goods, automotive parts and interior materials, medical devices and tools, building materials, tools, toys, and general merchandise, as well as grips that require a good fit and feel when held by a person, and applications that require impact protection when in contact with or colliding with the human body or other objects.

[0100] (Method for manufacturing multilayer molded bodies) The method for manufacturing a multilayer molded article according to this embodiment includes the steps of: molding the polar group-containing thermoplastic resin to obtain a molded article; and, with the obtained molded article placed in a mold, injecting the thermoplastic elastomer composition of this embodiment into the gap between the mold and the molded article and heat-sealing it. Generally, a preferred method involves producing a molded article of a polar group-containing thermoplastic resin, inserting the molded article into a mold, and filling the gaps in the mold with pellets of a thermoplastic elastomer composition and heat-sealing them. Furthermore, a preferred method for manufacturing a multilayer molded article is the insert molding method, which involves first molding a molded article of a polar group-containing thermoplastic resin, then fitting it into another mold, injecting a thermoplastic elastomer composition into the gap, and heat-sealing it. Furthermore, a two-color molding method is also preferred, in which a single injection molding machine has a configuration with two or more cylinders, in which a polar group-containing thermoplastic resin is first molded, and then a part of the mold is changed to create a gap between the polar group-containing thermoplastic resin and the mold, and a thermoplastic elastomer composition is injected into this gap from another cylinder. The multilayer molded article of this embodiment, having a thermoplastic elastomer composition layer and a polar group-containing thermoplastic resin layer, can be manufactured by any molding method. The molding temperature is not particularly limited, but 150°C to 280°C is preferred. [Examples]

[0101] The present invention will be described in detail below with reference to specific examples and comparative examples, but the present invention is not limited in any way by the following examples and comparative examples. First, the evaluation methods and physical property measurement methods applied to the examples and comparative examples are shown below.

[0102] [Evaluation method for hydrogenated block copolymers (a-1) and (a-2)] ((1) Weight-average molecular weight, number-average molecular weight, peak molecular weight, molecular weight distribution) The weight-average molecular weight (Mw), number-average molecular weight (Mn), peak molecular weight (weight-reduced molecular weight at the peak position; PMw), and molecular weight distribution (Mw / Mn) of hydrogenated block copolymers (a-1) and (a-2) were determined based on the molecular weight of the peaks in the chromatogram, using a calibration curve (created using the peak molecular weight of standard polystyrene) obtained from measurements of commercially available standard polystyrene. For measurement, we used HLC-8320ECOSEC acquisition software, and for analysis, we used HLC-8320ECOSEC analysis software. (Measurement conditions) GPC; HLC-8320GPC (manufactured by Tosoh Corporation) Detector; RI Detection sensitivity: 3 MV / min Sampling pitch: 600 MSEC Columns: TSKGEL SUPERHZM-N (6MMI.D x 15CM) 4 pieces (manufactured by Tosoh Corporation) Solvent; THF Flow rate ;0.6ML / min Concentration ;0.5MG / ML Column temperature: 40°C Injection volume: 20ML

[0103] ((2) Total vinyl aromatic monomer content (total styrene content)) A certain amount of hydrogenated block copolymer was dissolved in chloroform and measured using a UV spectrophotometer (Shimadzu Corporation, UV-2450). The styrene content was calculated using a calibration curve based on the peak intensity at the absorption wavelength (262 nm) attributed to styrene.

[0104] ((3) Styrene content in polystyrene block A in hydrogenated block copolymers (a-1) and (a-2)) The styrene content in polystyrene block A within the hydrogenated block copolymer was determined by oxidative decomposition of the hydrogenated block copolymer (described later) using t-butyl hydroperoxide with osmium tetroxide as a catalyst, followed by precipitation with methanol, solid-liquid separation, and measurement of the precipitate using an ultraviolet spectrophotometer (Shimadzu Corporation, UV-2450). The styrene content in polystyrene block A was calculated from the weight ratio of the value obtained using a calibration curve from the peak intensity of the absorption wavelength (262 nm) attributable to styrene, and the amount added during manufacturing.

[0105] ((4) Styrene content in polystyrene block A' in hydrogenated block copolymer (a-2)) The styrene content in polystyrene block A' in the hydrogenated block copolymer (a-2) was calculated using the following formula. (calculation formula) Styrene content in polystyrene block A' = ((Total styrene content - Styrene content in polystyrene block A) / Amount of styrene and butadiene added during the manufacture of block A') × 100

[0106] ((5) Amount of vinyl binding) The amount of vinyl bonds in the polybutadiene block within the block copolymer was measured using nuclear magnetic resonance (NMR) under the following conditions. In the table below, B represents the polybutadiene block. After the polymerization reaction was complete, a large amount of methanol was added to the reaction solution to precipitate and recover the block copolymer. Next, the block copolymer was extracted with acetone, and the extract was vacuum-dried. 1 Used as a sample for H-NMR measurement. 1The conditions for H-NMR measurement are described below. (Measurement conditions) Measuring instrument: JNM-LA400 (manufactured by JEOL) Solvent: Deuterated chloroform Sample concentration: 50 mg / ml Observation frequency: 400MHz Chemical shift standard: TMS (tetramethylsilane) Pulse delay: 2.904 seconds Number of scans: 64 Pulse width: 45° Measurement temperature: 26℃ The amount of vinyl bonding was determined by the ratio of the total area of ​​the 1,2-bond and 3,4-bond peaks to the total area of ​​all peaks related to conjugated diene monomer units (1,2-bond, 3,4-bond, 1,4-bond) in the obtained peaks.

[0107] (6) Hydrogenation rate The hydrogenation rate of double bonds in conjugated diene monomer units in block copolymers was measured using nuclear magnetic resonance (NMR) under the same conditions as described above for (5) vinyl bond amount. The hydrogenation rate was determined by calculating the ratio of the total area of ​​the hydrogenated 1,2-bond, hydrogenated 3,4-bond, and hydrogenated 1,4-bond peaks to the total area of ​​all peaks related to double bonds in the conjugated diene monomer unit (1,2-bond, 3,4-bond, 1,4-bond) in the obtained peaks.

[0108] ((7) Content of terminal polybutadiene blocks) The content of terminal polybutadiene blocks in the block copolymer was determined by the amount of monomer added during production and by confirming the polymerization reaction rate of each block using gas chromatography (GC). <Confirmation of polymerization reaction rate of each polymer block in block copolymers> Samples were prepared by sampling polymer solutions at each step of the polymerization process of the block copolymer before hydrogenation, and then adding approximately 20 mL of each sample to a sealed 100 mL bottle containing 0.50 mL of n-propylbenzene and approximately 20 mL of toluene as internal standards. The sample was measured using a gas chromatograph (Shimadzu Corporation: GC-14B) equipped with a backed column supported with apiezon grease. The amount of residual monomer in the polymer solution was determined from the calibration curves for butadiene monomer and styrene monomer obtained in advance, and it was confirmed that the polymerization rate of butadiene monomer and styrene monomer was 100%. The polymerization rate of butadiene was measured at a constant temperature of 90°C, while the polymerization rate of styrene was measured under conditions of heating from 90°C (hold for 10 minutes) to 150°C (10°C / min).

[0109] (8) Amount of acid anhydride group added The amount of acid anhydride groups added was defined as the amount (mass%) of acid anhydride groups that underwent the addition reaction in the total hydrogenated block copolymer. The measurement method involved first boiling the block copolymer in acetone for 60 minutes, then vacuum drying it, and finally dissolving it in toluene. Next, phenolphthalein indicator was added, and the mixture was titrated with a methanol solution of sodium methylate (CH3ONa). The amount of acid anhydride added was calculated from the amount of sodium methylate added to the acid anhydride groups.

[0110] [Manufacturing of thermoplastic elastomer compositions] (Examples 1-25), (Comparative Examples 1-15) Based on the mixing ratios (parts by mass) shown in the table below, the mixture was melt-kneaded at a set temperature of 230°C using a twin-screw extruder (TEX-30αII, manufactured by Japan Steel Works, Ltd., cylinder bore diameter 30 mm) to obtain pellets of thermoplastic elastomer composition.

[0111] [Method for evaluating thermoplastic elastomer compositions] (9) Melt Flow Rate (MFR) The melt flow rate (MFR) of the thermoplastic elastomer composition pellets obtained as described above was measured in accordance with ASTM D1238 under conditions of 230°C and a load of 2.16 kg.

[0112] ((10) Odor sensory test) 100 g of a thermoplastic elastomer composition pellet was placed in a 500 mL pressure-resistant glass bottle, sealed, heated at 70°C for 1 hour, and then left at room temperature for 48 hours. Subsequently, 10 subjects detected an odor from the mouth of the glass bottle. The determination was made using the average value of the odor intensity index shown below. ○: Odor intensity index less than 3, ×: Odor intensity index 3 or higher. ○ was evaluated as being practically good. <Odor Intensity Index> 0; Odorless, 1; Barely detectable odor, 2; Weak odor that can be identified, 2.5; Between 2 and 3, 3; Easily detectable odor, 3.5; Between 3 and 4, 4; Strong odor, 5 Intense odor

[0113] [Preparation of press sheet] Using the thermoplastic elastomer composition pellets obtained as described above, a mold (size: 110mm x 220mm x 2mm thick) was used in a 50t electric press manufactured by Toho Press Works, at 200°C and 0.5 kgf / cm². 2 Preheating for 5 minutes under the following pressurized conditions: 200°C, 100 kgf / cm² 2 A 2mm thick press sheet was produced by pressing it for 2 minutes under the specified pressure conditions. The physical properties of the obtained press sheet were measured according to the measurement method described below.

[0114] [Method for evaluating press sheets] ((11) Hardness) Measurements were taken using a Type A durometer in accordance with JIS K6253. We determined that a Shore A hardness of 90 or less indicates sufficient flexibility for practical use, while a Shore A hardness of 80 or less indicates adequate flexibility.

[0115] ((12) Tensile stress, tensile stress, tensile elongation at fracture, tensile elongation at fracture) In accordance with JIS K6251, a tensile test was conducted using a No. 3 dumbbell at a crosshead speed of 500 mm / min as described below. Tensile stress (M300)... The stress was measured when the material was stretched to 300%. Tensile breaking strength (Tb)... The stress at the time of fracture was measured. If Tb is 2 MPa or higher, it is considered to have sufficient mechanical strength for practical use, and if it is 4 MPa or higher, it is considered to have sufficient mechanical strength. Tensile elongation at fracture (Eb)... The elongation at the time of fracture was measured. If Eb is 500% or more, it was judged to have sufficient flexibility.

[0116] ((13) Dunlop rebound elasticity) In accordance with BS903, the Dunlop rebound elasticity was measured at 23°C using a Dunlop rebound elasticity tester. We determined that a percentage of 30% or higher indicates a practically acceptable tactile sensation.

[0117] ((14) 40°C compression set) In accordance with the JIS K6301 compression set test, six 2mm thick press sheets were punched out into 29mm diameter circles and stacked. The initial thickness of the stacked sheets was measured at 23°C, and then the sheets were compressed by 25% and left in a 40°C oven for 22 hours. After removal, the compression was released, and the sheets were left at 23°C for 30 minutes. The residual strain rate was then determined. A residual strain rate of 70% or less was considered to indicate sufficient deformation recovery for practical use.

[0118] ((15) Color difference) In accordance with JIS Z8781-4, the b* value (yellowness) of the press sheet of the thermoplastic elastomer composition obtained in the above-mentioned [manufacturing of thermoplastic elastomer] was measured using a color difference meter [color meter ZE6000 (product name)] manufactured by Nippon Denshoku Kogyo Co., Ltd. The measurement method was the reflection method, with a sheet placed on a 30mm diameter sample stage, and a white sample holder placed on top of it for measurement. The judgment was made based on the following criteria. ○ indicates a b* value of less than 10, and × indicates a b* value of 10 or more. ○ is considered to be practically good.

[0119] ((16) Transparency) In accordance with JIS K7136, the haze value of a 2 mm thick press sheet of the thermoplastic elastomer composition obtained in the above-mentioned [manufacturing of thermoplastic elastomer] was measured using a haze meter [manufactured by Suga Test Instruments Co., Ltd., product name HZ-V3], and the transparency was evaluated. We determined that data with a haze value exceeding 85% lacked transparency, while data with a haze value of 85% or less was considered transparent.

[0120] [Manufacturing of multilayer molded products] Using the pellets of the thermoplastic elastomer composition obtained in the above [Manufacturing of Thermoplastic Elastomer], a pre-molded polar group-containing thermoplastic resin molded product measuring 95 mm x 145 mm x 2 mm thick was inserted into the mold cavity of an injection molding machine FNX110III-18A (manufactured by Nissei Plastic Industrial Co., Ltd.), and a thermoplastic elastomer composition measuring 100 mm x 150 mm x 2 mm thick was injection molded onto its surface. The injection molding conditions were as follows: resin temperature: 240°C, injection speed: 40 mm / second, injection time: 10 seconds, mold temperature: 40°C, and cooling time: 30 seconds.

[0121] [Evaluation method for multilayer molded bodies] ((16) Heat fusion strength) The thermal fusion strength between the thermoplastic elastomer composition and the polar group-containing thermoplastic resin was measured by a 90-degree peel test using the multilayer molded body described above. A 10 mm wide cut was made on the thermoplastic elastomer composition side of the multilayer molded body, and several centimeters of the end were peeled off beforehand. At the peeled portion, the layer consisting of the thermoplastic elastomer composition and the layer consisting of the polar group-containing thermoplastic resin were fixed separately to the chucks of a tensile testing machine [MinebeaMitsumi Inc., TGE-500N (product name)]. The two layers were peeled off by pulling the layer consisting of the thermoplastic elastomer composition and the layer consisting of the polar group-containing thermoplastic resin at 300 mm / min in the 90° direction. The tensile force applied during peeling was defined as the thermal fusion strength (N / cm) of the multilayer molded body of the thermoplastic elastomer composition and the polar group-containing thermoplastic resin, and was evaluated according to the following evaluation criteria. The ratings were categorized as follows: 1 to 5, with 5 indicating extremely excellent performance and 4 indicating good practical performance. <Heat fusion strength evaluation criteria> 5:20N / cm or more 4: 10 N / cm or more and less than 20 N / cm 3: 5 N / cm or more and less than 10 N / cm 2: 1 N / cm or more and less than 5 N / cm Less than 1:1 N / cm

[0122] [Components used in the manufacture of the thermoplastic elastomer composition] The following describes each component used in the production of the thermoplastic elastomer composition.

[0123] (Preparation of hydrogenated catalyst) The hydrogenation catalyst used in the production of the hydrogenated block copolymer described later was prepared by the following method. A reaction vessel equipped with a stirring device was purged with nitrogen, and 1 liter of dried and purified cyclohexane was charged into it. Next, 100 mmol of bis(η5-cyclopentadienyl)titanium dichloride was added. While stirring thoroughly, an n-hexane solution containing 200 mmol of trimethylaluminum was added, and the mixture was reacted at room temperature for approximately 3 days to obtain a hydrogenated catalyst.

[0124] (Hydrogenated block copolymer (1)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, followed by the addition of 0.062 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, and 0.34 moles of tetramethylethylenediamine (hereinafter, TMEDA) per mole of n-butyllithium. Polymerization was then carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 68 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 40 minutes. Finally, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0125] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was complete, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer to 100 parts by mass of the block copolymer to obtain hydrogenated block copolymer (1).

[0126] The obtained hydrogenated block copolymer (1) had a total styrene content of 31.8% by mass, a styrene content of 98.7% by mass in polystyrene block A, a vinyl bond content of 35.5 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 296,000 for the entire polymer, and a molecular weight distribution of 1.21. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.5%.

[0127] (Hydrogenated block copolymer (2)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, followed by the addition of 0.088 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, and 0.34 moles of tetramethylethylenediamine (hereinafter, TMEDA) per mole of n-butyllithium. Polymerization was then carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 68 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 40 minutes. Finally, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0128] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was complete, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer at a rate of 0.3 parts by mass per 100 parts by mass of the block copolymer to obtain hydrogenated block copolymer (2).

[0129] The obtained hydrogenated block copolymer (2) had a total styrene content of 32.3% by mass, a styrene content of 99.2% by mass in polystyrene block A, a vinyl bond content of 34.6 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 176,000 for the entire polymer, and a molecular weight distribution of 1.23. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.2%.

[0130] (Hydrogenated block copolymer (3)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, followed by the addition of 0.062 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, and 0.34 moles of tetramethylethylenediamine (hereinafter, TMEDA) per mole of n-butyllithium. Polymerization was then carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 68 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 40 minutes. Finally, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0131] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 70 ppm of titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was complete, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer in an amount of 0.3 parts by mass per 100 parts by mass of the block copolymer to obtain hydrogenated block copolymer (3).

[0132] The obtained hydrogenated block copolymer (3) had a total styrene content of 32.1% by mass, a styrene content of 99.1% by mass in polystyrene block A, a vinyl bond content of 35.1 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 293,000 for the entire polymer, and a molecular weight distribution of 1.19. In addition, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 70.8%.

[0133] (Hydrogenated block copolymer (4)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, followed by the addition of 0.062 parts by mass of n-butyllithium per 100 parts by mass of total monomer, and 0.25 moles of tetramethylethylenediamine (hereinafter, TMEDA) per mole of n-butyllithium. Polymerization was then carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 68 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 40 minutes. Finally, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0134] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was complete, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer at a rate of 0.3 parts by mass per 100 parts by mass of polymer to obtain hydrogenated block copolymer (4).

[0135] The obtained hydrogenated block copolymer (4) had a total styrene content of 31.9% by mass, a styrene content of 98.9% by mass in polystyrene block A, a vinyl bond content of 28.2 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 289,000 for the entire polymer, and a molecular weight distribution of 1.21. In addition, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.3%.

[0136] (Hydrogenated block copolymer (5)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, after introducing a cyclohexane solution containing 16 parts by mass of styrene monomer, 0.060 parts by mass of n-butyllithium was added per 100 parts by mass of all monomers, and 0.55 mol of tetramethylethylenediamine (hereinafter referred to as TMEDA) was added per 1 mol of n-butyllithium, followed by polymerization at 70 °C for 25 minutes. Next, a cyclohexane solution containing 68 parts by mass of 1,3-butadiene monomer was added, and polymerization was carried out at 70 °C for 40 minutes. Finally, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, and polymerization was carried out at 70 °C for 25 minutes. After completion of the polymerization reaction, 0.95 mol of methanol was added per 1 mol of n-butyllithium to deactivate the reaction catalyst, and a block copolymer was obtained.

[0137] Next, 100 ppm of the hydrogenation catalyst as titanium per 100 parts by mass of the block copolymer was added to the obtained block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85 °C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate as a stabilizer was added per 100 parts by mass of the polymer to obtain a hydrogenated block copolymer (5).

[0138] The obtained hydrogenated block copolymer (5) had a total styrene content of 32.2% by mass, a styrene content in the polystyrene block A of 98.8% by mass, a vinyl bond amount before hydrogenation in the polybutadiene block of 48.7 mol%, a weight average molecular weight of the entire polymer of 302,000, and a molecular weight distribution of 1.24. Also, the hydrogenation rate of the aliphatic double bonds derived from 1,3-butadiene was 99.4%.

[0139] (Hydrogenated block copolymer (6)) A batch polymerization was carried out by cleaning, drying, and nitrogen substitution of a stirring device with an internal volume of 100 L and a jacketed tank reactor. First, a cyclohexane solution containing 20 parts by mass of styrene monomer was added, followed by the addition of 0.080 parts by mass of n-butyllithium per 100 parts by mass of total monomer and 1.2 moles of TMEDA per mole of n-butyllithium, and polymerization was carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 80 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 40 minutes. After the polymerization reaction was complete, tetramethoxysilane (hereinafter also referred to as "TMS") was added to a molar ratio of Si to Li (Si / Li) of 0.24 moles, and the mixture was stirred for 20 minutes. Then, methanol was added at a rate of 0.1 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0140] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (6).

[0141] The obtained hydrogenated block copolymer (6) had a total styrene content of 20.3% by mass, a styrene content of 98.5% by mass in polystyrene block A, a vinyl bond content of 58.6 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 453,000 for the entire polymer, and a molecular weight distribution of 1.28. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.3%.

[0142] (Hydrogenated block copolymer (7)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added. Then, 0.109 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.6 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 20 minutes. Next, a cyclohexane solution containing 18 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 59 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1 hour. Finally, a cyclohexane solution containing 18 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0143] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (7).

[0144] The obtained hydrogenated block copolymer (7) had a total styrene content of 36.2% by mass, a styrene content of 99.1% by mass in polystyrene block A, a vinyl bond content of 76.2 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 137,000 for the entire polymer, and a molecular weight distribution of 1.18. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.4%.

[0145] (Hydrogenated block copolymer (8)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added. Then, 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.6 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 20 minutes. Next, a cyclohexane solution containing 22 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 52 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1 hour. Finally, a cyclohexane solution containing 21 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0146] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (8).

[0147] The obtained hydrogenated block copolymer (8) had a total styrene content of 43.2% by mass, a styrene content of 99.2% by mass in polystyrene block A, a vinyl bond content of 77.8 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 108,000 for the entire polymer, and a molecular weight distribution of 1.19. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.5%.

[0148] (Hydrogenated block copolymer (9)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added. Then, 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.4 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 20 minutes. Next, a cyclohexane solution containing 22 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 52 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1 hour. Finally, a cyclohexane solution containing 21 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0149] Next, the hydrogenation catalyst was added to the obtained polymer at a concentration of 70 ppm titanium per 100 parts by mass of polymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of polymer to obtain a hydrogenated block copolymer (9).

[0150] The obtained hydrogenated block copolymer (9) had a total styrene content of 42.6% by mass, a styrene content of 98.9% by mass in polystyrene block A, a vinyl bond content of 73.2 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 113,000 for the entire polymer, and a molecular weight distribution of 1.20. In addition, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 75.7%.

[0151] (Hydrogenated block copolymer (10)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, after introducing a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer, 0.25 parts by mass of n-butyllithium with respect to 100 parts by mass of all monomers, 1.6 moles of TMEDA with respect to 1 mole of n-butyllithium, and further 0.04 moles of sodium-t-pentoxide with respect to 1 mole of n-butyllithium were added, and polymerization was carried out at 60 °C for 20 minutes. Next, a cyclohexane solution containing 28 parts by mass of styrene monomer was added and polymerization was carried out at 70 °C for 30 minutes. Further, a cyclohexane solution containing 40 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60 °C for 1 hour. Finally, a cyclohexane solution containing 27 parts by mass of styrene monomer was added and polymerization was carried out at 70 °C for 30 minutes. After completion of the polymerization reaction, 0.95 moles of methanol with respect to 1 mole of n-butyllithium was added to deactivate the reaction catalyst, and a block copolymer was obtained.

[0152] Next, 100 ppm of the hydrogenation catalyst as titanium per 100 parts by mass of the block copolymer was added to the obtained block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85 °C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate as a stabilizer was added per 100 parts by mass of the polymer to obtain a hydrogenated block copolymer (10).

[0153] [[ID=​​​​​​​​First, a cyclohexane solution containing 22 parts by mass of styrene monomer was added, followed by the addition of 0.125 parts by mass of n-butyllithium per 100 parts by mass of total monomer, 1.6 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium. Polymerization was carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 57 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1 hour. Finally, a cyclohexane solution containing 21 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0155] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (11).

[0156] The obtained hydrogenated block copolymer (11) had a total styrene content of 43.1% by mass, a styrene content of 99.1% by mass in polystyrene block A, a vinyl bond content of 76.8 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 103,000 for the entire polymer, and a molecular weight distribution of 1.14. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.6%.

[0157] (Hydrogenated block copolymer (12)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added, followed by the addition of 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer and 0.8 moles of TMEDA per mole of n-butyllithium, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution containing 22 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 52 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 40 minutes. Finally, a cyclohexane solution containing 21 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0158] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (12).

[0159] The obtained hydrogenated block copolymer (12) had a total styrene content of 43.1% by mass, a styrene content of 99.0% by mass in polystyrene block A, a vinyl bond content of 62.5 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 102,000 for the entire polymer, and a molecular weight distribution of 1.13. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.4%.

[0160] (Hydrogenated block copolymer (13)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 0.5 parts by mass of 1,3-butadiene monomer was added. Then, 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.6 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 10 minutes. Next, a cyclohexane solution containing 22 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 56.5 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1 hour. Finally, a cyclohexane solution containing 21 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0161] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (13).

[0162] The obtained hydrogenated block copolymer (13) had a total styrene content of 43.1% by mass, a styrene content of 99.5% by mass in polystyrene block A, a vinyl bond content of 76.8 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 103,000 for the entire polymer, and a molecular weight distribution of 1.13. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.1%.

[0163] (Hydrogenated block copolymer (14)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 13 parts by mass of 1,3-butadiene monomer was added. Then, 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.6 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 30 minutes. Next, a cyclohexane solution containing 22 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 44 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1 hour. Finally, a cyclohexane solution containing 21 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0164] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (14).

[0165] The obtained hydrogenated block copolymer (14) had a total styrene content of 43.4% by mass, a styrene content of 99.3% by mass in polystyrene block A, a vinyl bond content of 78.1 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 104,000 for the entire polymer, and a molecular weight distribution of 1.15. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.4%.

[0166] (Hydrogenated block copolymer (15)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added. Then, 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.9 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 20 minutes. Next, a cyclohexane solution containing 22 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 52 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1 hour. Finally, a cyclohexane solution containing 21 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0167] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (15).

[0168] The obtained hydrogenated block copolymer (15) had a total styrene content of 43.2% by mass, a styrene content of 98.9% by mass in polystyrene block A, a vinyl bond content of 83.6 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 107,000 for the entire polymer, and a molecular weight distribution of 1.18. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.2%.

[0169] (Hydrogenated block copolymer (16)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, followed by the addition of 0.140 parts by mass of n-butyllithium per 100 parts by mass of total monomer, 0.7 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium. Polymerization was carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 7 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 15 minutes. Then, a cyclohexane solution containing 33 parts by mass of styrene monomer and 20 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 1 hour. Next, a cyclohexane solution containing 15 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Finally, a cyclohexane solution containing 9 parts by mass of 1,3-butadiene monomer was added, and polymerization was carried out at 70°C for 15 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0170] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (16).

[0171] The obtained hydrogenated block copolymer (16) had a total styrene content of 64.1% by mass, a styrene content of 98.8% by mass in polystyrene block A, a styrene content of 60.6% by mass in polystyrene block A', a vinyl bond content of 65.3 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 94,000 for the entire polymer, and a molecular weight distribution of 1.21. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.4%.

[0172] (Hydrogenated block copolymer (17)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 16 parts by mass of styrene monomer was added, followed by the addition of 0.130 parts by mass of n-butyllithium per 100 parts by mass of total monomer, 0.7 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium. Polymerization was carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 7 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 15 minutes. Then, a cyclohexane solution containing 29 parts by mass of styrene monomer and 24 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 1 hour. Next, a cyclohexane solution containing 15 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Finally, a cyclohexane solution containing 9 parts by mass of 1,3-butadiene monomer was added, and polymerization was carried out at 70°C for 15 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0173] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (17).

[0174] The obtained hydrogenated block copolymer (17) had a total styrene content of 60.2% by mass, a styrene content of 98.6% by mass in polystyrene block A, a styrene content of 52.1% by mass in polystyrene block A', a vinyl bond content of 64.8 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 106,000 for the entire polymer, and a molecular weight distribution of 1.25. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 98.6%.

[0175] (Hydrogenated block copolymer (18)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added. Then, 0.086 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.5 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 20 minutes. Next, a cyclohexane solution containing 7 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 20 minutes. Then, a cyclohexane solution containing 82 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1.5 hours. Finally, a cyclohexane solution containing 6 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 20 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0176] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (18).

[0177] The obtained hydrogenated block copolymer (18) had a total styrene content of 13.4% by mass, a styrene content of 99.3% by mass in polystyrene block A, a vinyl bond content of 76.3 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 183,000 for the entire polymer, and a molecular weight distribution of 1.22. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.6%.

[0178] (Hydrogenated block copolymer (19)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added, followed by the addition of 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer and 0.4 moles of TMEDA per mole of n-butyllithium, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution containing 22 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 51 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 40 minutes. Finally, a cyclohexane solution containing 22 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0179] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (19).

[0180] The obtained hydrogenated block copolymer (19) had a total styrene content of 44.1% by mass, a styrene content of 99.5% by mass in polystyrene block A, a vinyl bond content of 39.6 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 102,000 for the entire polymer, and a molecular weight distribution of 1.13. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.2%.

[0181] (Hydrogenated block copolymer (20)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added. Then, 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.4 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 20 minutes. Next, a cyclohexane solution containing 38 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 35 minutes. Then, a cyclohexane solution containing 19 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 40 minutes. Finally, a cyclohexane solution containing 38 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 35 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0182] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (20).

[0183] The obtained hydrogenated block copolymer (20) had a total styrene content of 75.6% by mass, a styrene content of 99.3% by mass in polystyrene block A, a vinyl bond content of 75.1 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 104,000 for the entire polymer, and a molecular weight distribution of 1.19. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.5%.

[0184] (Hydrogenated block copolymer (21)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 33 parts by mass of styrene monomer was added, followed by the addition of 0.198 parts by mass of n-butyllithium per 100 parts by mass of the total monomer and 0.4 moles of TMEDA per mole of n-butyllithium, and polymerization was carried out at 70°C for 30 minutes. Next, a cyclohexane solution containing 34 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 30 minutes. Finally, a cyclohexane solution containing 33 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 30 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0185] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (21).

[0186] The obtained hydrogenated block copolymer (21) had a total styrene content of 65.7% by mass, a polystyrene block content of 98.9% by mass, a vinyl bond content in the polybutadiene block before hydrogenation of 40.6 mol%, a weight-average molecular weight of 57,000 for the entire polymer, and a molecular weight distribution of 1.16. Furthermore, the hydrogenation rate of the aliphatic double bonds derived from 1,3-butadiene was 99.5%.

[0187] (Hydrogenated block copolymer (22)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 10 parts by mass of styrene monomer was added, followed by the addition of 0.138 parts by mass of n-butyllithium per 100 parts by mass of total monomer and 0.8 moles of TMEDA per mole of n-butyllithium, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution containing 47 parts by mass of styrene monomer and 34 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 50 minutes. Finally, a cyclohexane solution containing 9 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 20 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0188] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (22).

[0189] The obtained hydrogenated block copolymer (22) had a total styrene content of 66.2% by mass, a styrene content of 99.1% by mass in polystyrene block A, a styrene content of 58.2% by mass in polystyrene block A', a weight-average molecular weight of 95,000 for the entire polymer, and a molecular weight distribution of 1.22. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.0%.

[0190] (Hydrogenated block copolymer (23)) The hydrogenated block copolymer (8) was desolvented, dried, and pelletized using a single-screw extruder. Then, 2.1 parts by mass of maleic anhydride and 0.12 parts by mass of 2,5-dimethyl-2,5-di(t-butylperoxy)hexane were added to 100 parts by mass of the hydrogenated block copolymer (8), and an addition reaction was carried out using a twin-screw extruder at a set temperature of 200°C to obtain the hydrogenated block copolymer (23). The obtained hydrogenated block copolymer (23) had an addition amount of acid anhydride groups by maleic anhydride of 1.8% by mass.

[0191] (Hydrogenated block copolymer (24)) The hydrogenated block copolymer (18) was desolvented, dried, and pelletized using a single-screw extruder. Then, 2.1 parts by mass of maleic anhydride and 0.12 parts by mass of 2,5-dimethyl-2,5-di(t-butylperoxy)hexane were added to 100 parts by mass of the hydrogenated block copolymer (18), and an addition reaction was carried out using a twin-screw extruder at a set temperature of 200°C to obtain the hydrogenated block copolymer (24). The obtained hydrogenated block copolymer (24) had an addition amount of acid anhydride groups by maleic anhydride of 1.5% by mass.

[0192] (Hydrogenated block copolymer (25)) The hydrogenated block copolymer (22) was desolvented, dried, and pelletized using a single-screw extruder. Then, 2.1 parts by mass of maleic anhydride and 0.12 parts by mass of 2,5-dimethyl-2,5-di(t-butylperoxy)hexane were added to 100 parts by mass of the hydrogenated block copolymer (22), and an addition reaction was carried out using a twin-screw extruder at a set temperature of 200°C to obtain the hydrogenated block copolymer (25). The obtained hydrogenated block copolymer (25) had an addition amount of acid anhydride groups by maleic anhydride of 1.1% by mass.

[0193] (Hydrogenated block copolymer (26)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 11 parts by mass of styrene monomer was added. Then, 0.10 parts by mass of n-butyllithium per 100 parts by mass of total monomer, 0.8 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 70°C for 25 minutes. Next, a cyclohexane solution containing 10 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 15 minutes. Then, a cyclohexane solution containing 46 parts by mass of styrene monomer and 19 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 1 hour. Next, a cyclohexane solution containing 9 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Finally, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added, and polymerization was carried out at 70°C for 15 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0194] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (26).

[0195] The obtained hydrogenated block copolymer (26) had a total styrene content of 66.4% by mass, a styrene content of 99.4% by mass in polystyrene block A, a styrene content of 69.2% by mass in polystyrene block A', a vinyl bond content of 65.8 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 136,000 for the entire polymer, and a molecular weight distribution of 1.19. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.3%.

[0196] (Hydrogenated block copolymer (27)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added. Then, 0.215 parts by mass of n-butyllithium per 100 parts by mass of the total monomer, 1.6 moles of TMEDA per mole of n-butyllithium, and 0.04 moles of sodium-t-pentoxide per mole of n-butyllithium were added, and polymerization was carried out at 60°C for 20 minutes. Next, a cyclohexane solution containing 19 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 57 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 60°C for 1 hour. Finally, a cyclohexane solution containing 19 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0197] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (27).

[0198] The obtained hydrogenated block copolymer (27) had a total styrene content of 37.6% by mass, a styrene content of 99.1% by mass in polystyrene block A, a vinyl bond content of 77.5 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 54,000 for the entire polymer, and a molecular weight distribution of 1.16. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.5%.

[0199] (Hydrogenated block copolymer (28)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added, followed by the addition of 0.078 parts by mass of n-butyllithium per 100 parts by mass of the total monomer and 0.4 moles of TMEDA per mole of n-butyllithium, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution containing 34 parts by mass of styrene monomer was added, and polymerization was carried out at 70°C for 30 minutes. Next, a cyclohexane solution containing 28 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 30 minutes. Finally, a cyclohexane solution containing 33 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 30 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0200] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain hydrogenated block copolymer (28).

[0201] The obtained hydrogenated block copolymer (28) had a total styrene content of 66.7% by mass, a polystyrene block content of 99.3% by mass, a vinyl bond content in the polybutadiene block before hydrogenation of 40.3 mol%, a weight-average molecular weight of 195,000 for the entire polymer, and a molecular weight distribution of 1.14. Furthermore, the hydrogenation rate of the aliphatic double bonds derived from 1,3-butadiene was 99.2%.

[0202] (Hydrogenated block copolymer (29)) A stirring device with an internal volume of 100 L and a jacketed tank reactor were cleaned, dried, and nitrogen-purged before batch polymerization was performed. First, a cyclohexane solution containing 5 parts by mass of 1,3-butadiene monomer was added, followed by the addition of 0.125 parts by mass of n-butyllithium per 100 parts by mass of the total monomer and 0.4 moles of TMEDA per mole of n-butyllithium, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution containing 15 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. Then, a cyclohexane solution containing 65 parts by mass of 1,3-butadiene monomer was added and polymerization was carried out at 70°C for 40 minutes. Finally, a cyclohexane solution containing 15 parts by mass of styrene monomer was added and polymerization was carried out at 70°C for 25 minutes. After the polymerization reaction was complete, methanol was added at a rate of 0.95 moles per mole of n-butyllithium to deactivate the reaction catalyst and obtain a block copolymer.

[0203] Next, the hydrogenation catalyst was added to the obtained block copolymer at a concentration of 100 ppm titanium per 100 parts by mass of the block copolymer, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and a temperature of 85°C. After the hydrogenation reaction was completed, 0.3 parts by mass of octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate was added as a stabilizer per 100 parts by mass of the polymer to obtain a hydrogenated block copolymer (29).

[0204] The obtained hydrogenated block copolymer (29) had a total styrene content of 30.3% by mass, a styrene content of 99.5% by mass in polystyrene block A, a vinyl bond content of 41.2 mol% in the polybutadiene block before hydrogenation, a weight-average molecular weight of 103,000 for the entire polymer, and a molecular weight distribution of 1.16. Furthermore, the hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.5%.

[0205] (Polypropylene resin (b)) The following commercially available polypropylene resin (b) was used. Polypropylene resin (b): Sun Allomer Co., Ltd. PM801A, propylene homopolymer 9, MFR (230℃, 2.16kg) 13g / 10min

[0206] (Non-aromatic softeners (c)) The following commercially available non-aromatic softener (c) was used. Non-aromatic softener (c): Diana Process Oil PW90 manufactured by Idemitsu Kosan Co., Ltd., paraffin-based oil, weight-average molecular weight 530, kinematic viscosity (40℃) = 90.5 mm 2 / sec

[0207] [Components used in multilayer molded articles] (Thermoplastic resin containing polar groups) PC molded plate: Takiron CI Co., Ltd. PC1600, 95mm x 145mm x 2mm thick flat plate ABS molded plate: Sumitomo Bakelite Co., Ltd. EAR003, 95mm x 145mm x 2mm thick flat plate PC / ABS molded plate: Sumitomo Bakelite Co., Ltd., ROA EFN800-04, 95mm x 145mm x 2mm thick flat plate PMMA molded plate: Mitsubishi Chemical Corporation Acrylite L-100, 95mm x 145mm x 2mm thick flat plate PET molded plate: Takiron CI Co., Ltd. PET-6010, 95mm x 145mm x 2mm thick flat plate

[0208] Tables 1 to 3 below show the types, forms, and physical properties of hydrogenated block copolymers (1) to (29). In the table, A and A' are polymer blocks mainly composed of vinyl aromatic monomer units, B is a polymer block mainly composed of conjugated diene monomer units, and X is a coupling agent residue.

[0209] [Table 1]

[0210] [Table 2]

[0211] [Table 3]

[0212] Tables 4 to 7 below show the blending ratios and properties of the thermoplastic elastomer compositions of Examples 1 to 25 and Comparative Examples 1 to 15. Please note that in the table below, the numbers of the examples and comparative examples do not always correspond to the order in which they are listed.

[0213] [Table 4]

[0214] [Table 5]

[0215] [Table 6]

[0216] [Table 7]

[0217] This application is based on Japanese Patent Application No. 2022-081255, filed with the Japan Patent Office on 18 May 2022, the contents of which are incorporated herein by reference. [Industrial applicability]

[0218] The thermoplastic elastomer composition and multilayer molded articles of the present invention are free from problems such as odor and color, and have excellent moldability and heat adhesion strength, making them potentially industrially applicable as surface materials for polar resins and various sealing materials.

Claims

1. 100 parts by mass of hydrogenated block copolymer (a-1), 10 to 100 parts by mass of polypropylene resin (b), 50 to 300 parts by mass of a non-aromatic softening agent (c), It contains, Furthermore, the thermoplastic elastomer composition for multilayer molding that is heat-fused by injection molding contains a hydrogenated block copolymer (a-2), wherein both the hydrogenated block copolymer (a-1) and the hydrogenated block copolymer (a-2) are unmodified hydrogenated block copolymers, The content of the hydrogenated block copolymer (a-2) is 5 to 70% by mass relative to the total amount of the components (a-1), (a-2), (b), and (c). The hydrogenated block copolymer (a-1) satisfies the following requirements (1-1) to (1-4), The hydrogenated block copolymer (a-2) satisfies the following requirements (2-1) to (2-6): A thermoplastic elastomer composition for multilayer molding. (1-1): Contains polymer block A1 mainly composed of one or more styrene units and polymer block B1 mainly composed of one or more conjugated diene monomer units. (1-2): The total styrene content is 15% by mass or more and less than 35% by mass. (1-3): The weight-average molecular weight is between 150,000 and 550,000. (1-4): More than 50 mol% of the double bonds of the conjugated diene monomer unit are hydrogenated. (2-1): Contains polymer block A2 mainly composed of one or more styrene units and polymer block B2 mainly composed of one or more conjugated diene monomer units. (2-2): The styrene content in polymer block A2 is 50% by mass or more. (2-3): The total styrene content is 35% to 70% by mass. (2-4): The weight-average molecular weight is 30,000 or more and less than 150,000. (2-5): The amount of vinyl bonds in the conjugated diene monomer units in polymer block B2 before hydrogenation is 60 mol% to 95 mol%. (2-6): More than 50 mol% of the double bonds of the conjugated diene monomer unit are hydrogenated.

2. The hydrogenated block copolymer (a-2) It comprises at least two polymer blocks A2 mainly composed of styrene and at least two polymer blocks B2 mainly composed of conjugated diene monomer units, At least one of the polymer blocks B2 is located at the end of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the end is 1 to 10% by mass in the hydrogenated block copolymer (a-2). It does not have a peak with a weight-average molecular weight of 250,000 or more. The thermoplastic elastomer composition for multilayer molding according to claim 1.

3. The styrene content in polymer block A2 of the hydrogenated block copolymer (a-2) is 90% by mass or more. The thermoplastic elastomer composition for multilayer molding according to claim 2.

4. The total styrene content of the hydrogenated block copolymer (a-2) is greater than 40% by mass and less than or equal to 70% by mass. The thermoplastic elastomer composition for multilayer molding according to claim 2 or 3.

5. In the hydrogenated block copolymer (a-1), The amount of vinyl bonds in the conjugated diene monomer unit before hydrogenation is 30 mol% to 50 mol%, The thermoplastic elastomer composition for multilayer molding according to claim 2 or 3.

6. A thermoplastic elastomer composition layer for multilayer molding according to claim 1 or 2, An polarity group-containing thermoplastic resin layer, A multilayer molded body having the following characteristics.

7. An polarity group-containing thermoplastic resin layer, A thermoplastic elastomer composition layer comprising a hydrogenated block copolymer (a), a polypropylene resin (b), and a non-aromatic softener (c), A multilayer molded body having, The thermoplastic elastomer composition layer is provided in contact with the polar group-containing thermoplastic resin layer, The hydrogenated block copolymer (a) does not contain a modifying group. The hydrogenated block copolymer (a) is A hydrogenated block copolymer which is a hydrogenated product of a block copolymer having styrene and conjugated diene monomer units, The molecular weight peaks determined by GPC are one or more in the range of 30,000 to less than 150,000 and one in the range of 150,000 to 550,000. The hydrogenated block copolymer, whose molecular weight peak measured by GPC is between 30,000 and less than 150,000, has a total styrene content of 35% to 70% by mass, and the amount of vinyl bonds in the conjugated diene monomer unit before hydrogenation is 60 mol% to 95 mol%, The hydrogenated block copolymer with a molecular weight peak of 150,000 to 550,000 as measured by GPC has a total styrene content of 15% to less than 35% by mass. The hydrogenation rate of the double bond in the conjugated diene monomer unit is 50 mol% or more. Multilayered molded body.

8. The hydrogenated block copolymer (a) consists of hydrogenated block copolymer (a-1) and hydrogenated block copolymer (a-2), The above (a-1) satisfies the requirements of (1-1) to (1-4) below, The above (a-2) satisfies the requirements of (2-1) to (2-6) below, The thermoplastic elastomer composition layer contains (a-1) 100 parts by mass, (b) 10 to 100 parts by mass, and (c) 50 to 300 parts by mass. The content of (a-2) in the thermoplastic elastomer composition layer is 5 to 70% by mass relative to the total amount of components (a-1), (a-2), (b), and (c). The multilayer molded body according to claim 7. (1-1): Contains polymer block A1 mainly composed of one or more styrene units and polymer block B1 mainly composed of one or more conjugated diene monomer units. (1-2): The total styrene content is 15% by mass or more and less than 35% by mass. (1-3): The weight-average molecular weight is between 150,000 and 550,000. (1-4): More than 50 mol% of the double bonds of the conjugated diene monomer unit are hydrogenated. (2-1): Contains polymer block A2 mainly composed of one or more styrene units and polymer block B2 mainly composed of one or more conjugated diene monomer units. (2-2): The styrene content in polymer block A2 is 50% by mass or more. (2-3): The total styrene content is 35% to 70% by mass. (2-4): The weight-average molecular weight is 30,000 or more and less than 150,000. (2-5): The amount of vinyl bonds in the conjugated diene monomer units in polymer block B2 before hydrogenation is 60 mol% to 95 mol%. (2-6): More than 50 mol% of the double bonds of the conjugated diene monomer unit are hydrogenated.

9. The hydrogenated block copolymer (a-2) The polymer comprises at least two styrene-based polymer blocks A2 and at least two conjugated diene monomer units-based polymer blocks B2, wherein at least one of the polymer blocks B2 is located at the end of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the end is 1 to 10% by mass of the hydrogenated block copolymer (a-2). The total styrene content is greater than 40% by mass and less than or equal to 70% by mass. It does not have a peak with a weight-average molecular weight of 250,000 or more. The multilayer molded body according to claim 8.

10. The styrene content in polymer block A2 of the hydrogenated block copolymer (a-2) is 90% by mass or more. The multilayer molded article according to claim 8 or 9.

11. The polar group-containing thermoplastic resin is at least one selected from the group consisting of polycarbonate resin, ABS resin, polyester resin, acrylic resin, and mixtures thereof. The multilayer molded body according to claim 7.

12. The hydrogenated block copolymer (a-1) is The amount of vinyl bonds in the conjugated diene monomer unit before hydrogenation is 30 mol% to 50 mol%, The multilayer molded body according to claim 8.

13. A thermoplastic elastomer composition for use in a multilayer molded article according to claim 8 or 9, The multilayer molded body is formed by heat-sealing the polar group-containing thermoplastic resin layer and the thermoplastic elastomer composition layer by injection molding. Thermoplastic elastomer composition.

14. A method for manufacturing a multilayer molded article according to claim 8 or 9, A step of molding the polar group-containing thermoplastic resin to obtain a molded article, The process involves injecting the thermoplastic elastomer composition described in claim 13 into the gap between the mold and the molded body while the molded body is placed in the mold, and then heat-sealing it. A method for manufacturing a multilayered molded body.

Images