Block copolymers and adhesives

Abstract

This invention provides a block copolymer and adhesive that can exhibit balanced molding processability, adhesive properties and spreadability. When the composition ratio (molar ratio) of the structural units represented by formulas (1) to (4) in the polymer is set as p, q, r and s respectively, the block copolymer represented by formula (i) has a value α of 0.75 or more. The block copolymer comprises a polymer (A1) having a multi-branched structure with four or more polymer chains. The polymer chains have polymer blocks A and polymer blocks B. Polymer block A contains structural units derived from conjugated diene compounds. Polymer block B contains structural units derived from aromatic vinyl compounds. Some or all of the ends of the four or more polymer chains have functional groups F. The functional groups F contain at least one element selected from nitrogen, silicon, oxygen and sulfur.

Description

Technical Field

[0001] This invention relates to a block copolymer and an adhesive. Prior Technology

[0002] In the past, surface protective films have been used to cover the surfaces of optical components or various components such as metal plates and synthetic resin plates to protect them from contamination or damage. In addition, hydrogenated conjugated diene polymers have been proposed as materials for forming adhesive layers such as surface protective films (for example, see Patent Document 1).

[0003] Patent Document 1 discloses the following: A hydrogenated diene copolymer, formed by hydrogenating a block copolymer comprising at least two polymer blocks mainly composed of aromatic vinyl compounds and copolymer blocks of aromatic vinyl compounds and conjugated diene compounds, is used as the adhesive layer material. Furthermore, a hydrogenated diene copolymer, formed by hydrogenating a block copolymer comprising at least two polymer blocks mainly composed of conjugated diene compounds and having a vinyl bond content of less than 20 moles, and copolymer blocks of aromatic vinyl compounds and conjugated diene compounds, is used as the adhesive layer material. Patent Document 1 also discloses that, by ensuring that the total aromatic vinyl compound unit content of the hydrogenated diene copolymer is in a specified proportion and that the vinyl bond content derived from the conjugated diene compound is in a specified proportion, an adhesive film with excellent processability and adhesion is obtained in the material described in Patent Document 1. [Existing Technical Documents] [Patent Literature]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2005-170985 Summary of the Invention

[0005] [The problem that the invention aims to solve]

[0006] While the hydrogenated diene copolymer described in Patent Document 1 exhibits good processability, its adhesive properties (e.g., peel strength, initial adhesion to the substrate (tackiness), and the ability to maintain adhesion after bonding (low adhesion enhancement)) are not yet sufficient. Especially when used as a surface protective film for optical applications, excellent adhesion to polar resin substrates such as polycarbonate is required. Furthermore, the material used as the adhesive layer needs to have low rewinding force (unwinding force) when forming the film roll for adhesive film applications. However, it is difficult to develop a material that uniformly exhibits all these properties, and further improvements are required.

[0007] The present invention was made in view of the aforementioned issues, and its main objective is to provide a block copolymer that can exhibit balanced formability, adhesive properties and spreadability. [Methods for solving problems]

[0008] According to the present invention, the following block copolymers and adhesives are provided.

[0009] [1] A block copolymer is a block copolymer in which the value α represented by the following formula (i) is 0.75 or more when the structural units represented by the following formula (1), the following formula (2), the following formula (3) and the following formula (4) are respectively set as p, q, r and s in the polymer, wherein the block copolymer comprises 10% by mass or more of a polymer (A1) having four or more polymer chains and having a multi-branched structure, wherein the polymer chains have polymer blocks A and polymer blocks B, wherein the polymer blocks A comprise 70% by mass or more of structural units derived from conjugated diene compounds, wherein the polymer blocks B comprise 70% by mass or more of structural units derived from aromatic vinyl compounds, wherein a portion or all of the ends of the four or more polymer chains have functional groups F, wherein the functional groups F comprise at least one element selected from the group consisting of nitrogen, silicon, oxygen and sulfur. α=(p+(0.5×r)) / (p+q+(0.5×r)+s) …(i) [Chemistry 1]

[0010] [2] An adhesive obtained using the block copolymer of [1]. [The effects of the invention]

[0011] The block copolymers of the present invention provide adhesives with excellent processability, adhesion and spreadability. Implementation

[0012] The following describes in detail matters related to the implementation of the present invention. Furthermore, in this specification, the numerical range indicated by “~” represents the range of values ​​before and after the “~” as a lower and upper limit value.

[0013] Block copolymers The block copolymer of the present invention (hereinafter also referred to as "[A] block copolymer") is a conjugated diene block copolymer comprising polymer block A, which is mainly composed of structural units derived from conjugated diene compounds, and polymer block B, which is mainly composed of structural units derived from aromatic vinyl compounds. In the [A] block copolymer, when the composition ratio (molar ratio) of the structural units represented by the following formula (1), the following formula (2), the following formula (3), and the following formula (4) are respectively set as p, q, r, and s, the value α represented by the following formula (i) is 0.75 or more. α=(p+(0.5×r)) / (p+q+(0.5×r)+s) …(i) [Chemistry 2]

[0014] [A] Block copolymers comprise branched polymers that are polymers having a multi-branched structure. Specifically, [A] block copolymers comprise polymers (A1) comprising 10% or more by mass of a branched polymer having four or more polymer chains P1, relative to 100% by mass of the [A] block copolymer. The four or more polymer chains P1 of polymer (A1) each have polymer blocks A and B. A portion or all of the ends of the four or more polymer chains P1 have functional groups F, wherein the functional groups F comprise at least one element selected from the group consisting of nitrogen, silicon, oxygen, and sulfur. The structure of [A] block copolymers and their manufacturing methods are described in detail below.

[0015] <Polymer Block A> Polymer block A is a segment primarily composed of structural units derived from conjugated diene compounds. Examples of conjugated diene compounds constituting polymer block A include: 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, β-gold and farnesene, and chloroprene. Among these, 1,3-butadiene, isoprene, 1,3-pentadiene, and 2,3-dimethyl-1,3-butadiene are preferred in terms of obtaining polymers that are industrially usable and exhibit excellent physical properties; 1,3-butadiene and isoprene are more preferred. One or more of these conjugated diene compounds can be used alone or in combination.

[0016] Polymer block A may be a segment containing only a conjugated diene compound, or it may contain structural units derived from a monomer different from the conjugated diene compound (hereinafter also referred to as "other monomer a"). There are no particular limitations on other monomer a, as long as it is a monomer that can copolymerize with the conjugated diene compound, for example, aromatic vinyl compounds, acrylonitrile, methyl methacrylate, ethyl methacrylate, etc.

[0017] Polymer block A comprises at least 70% by mass of structural units derived from conjugated diene compounds relative to all structural units constituting polymer block A. If the proportion of structural units derived from conjugated diene compounds in polymer block A is less than 70% by mass, the adhesive force is insufficient, particularly tending to decrease initial tackiness (adhesion). Furthermore, it is difficult to adequately introduce crystalline block segments, which exhibit a structure similar to low-density polyethylene (LDPE) through hydrogenation, into the [A] block copolymer, leading to a tendency for increased adhesion or a greater force (unwinding force) required for rewinding when forming film rolls for adhesive film applications. From this perspective, the proportion of structural units derived from conjugated diene compounds in polymer block A is preferably 80% by mass or more, more preferably 90% by mass or more, more preferably 95% by mass or more, and particularly preferably 98% by mass or more.

[0018] Polymer block A is preferably a segment whose value β, as represented by the following formula (ii), exceeds 0.20. When the value β in polymer block A exceeds 0.20, it is preferred in terms of preventing the [A] block copolymer from becoming too stiff and thus improving the adhesion strength, and in terms of suppressing the increase of the spreading force. β=(p+q) / (p+q+(0.5×r)+s) …(ii) From the aforementioned perspective, the value of β in polymer block A is preferably 0.30 or more, more preferably 0.40 or more, even more preferably 0.50 or more, and particularly preferably more than 0.60. Furthermore, from the viewpoint of ensuring processability, the vinyl bond content of polymer block A is, for example, 0.85 or less.

[0019] Furthermore, in the hydrogenated polymer, the value β corresponds to the vinyl bond content (moles%) of the unhydrogenated polymer. "Vinyl bond content" is a value representing the proportion of structural units having 1,2-bonds relative to all structural units derived from conjugated dienes in the unhydrogenated polymer (or polymer block). The vinyl bond content of the unhydrogenated polymer is determined using a 1H-nuclear magnetic resonance (1H-NMR) instrument. For example, β = 0.20 indicates that the vinyl bond content of the polymer (or polymer block) is 20 moles.

[0020] <Polymer Block B> Polymer block B is a segment primarily composed of structural units derived from aromatic vinyl compounds. Examples of aromatic vinyl compounds constituting polymer block B include: styrene, tert-butylstyrene, α-methylstyrene, p-methylstyrene, p-ethylstyrene, divinylbenzene, 1,1-diphenylstyrene, vinylnaphthalene, vinylanthracene, N,N-diethyl-p-aminoethylstyrene, vinylpyridine, etc. Styrene is particularly preferred among these. One or more of these aromatic vinyl compounds may be used alone or in combination.

[0021] Polymer block B may be a segment containing only aromatic vinyl compounds, or it may contain structural units derived from monomers different from aromatic vinyl compounds (hereinafter also referred to as "other monomers b"). Other monomers b are not particularly limited as long as they are monomers capable of copolymerizing with aromatic vinyl compounds. Examples of other monomers b include conjugated dienes, acrylonitrile, methyl methacrylate, ethyl methacrylate, etc.

[0022] Polymer block B comprises at least 70% by mass of structural units derived from aromatic vinyl compounds, relative to all structural units constituting polymer block B. If the proportion of structural units derived from aromatic vinyl compounds in polymer block B is less than 70% by mass, the adhesiveness decreases, resulting in insufficient adhesion strength to the substrate (especially polar resins such as polycarbonate resin), or a tendency for adhesive reinforcement to occur due to reduced self-supporting properties of the adhesive. From this perspective, the proportion of structural units derived from aromatic vinyl compounds in polymer block B is preferably 80% by mass or more, more preferably 90% by mass or more, more preferably 95% by mass or more, and particularly preferably 98% by mass or more.

[0023] <Functional group F> The polymer (A1) has multiple polymer chains P1, some or all of which have functional groups F at their ends. The functional groups F contain at least one element selected from the group consisting of nitrogen, silicon, oxygen, and sulfur. In [A] block copolymers, the introduction of functional groups F into some or all of the free ends of the polymer (A1) can uniformly improve adhesive properties and processability. The functional groups F are preferably introduced into the ends of polymer blocks A or B.

[0024] Specific examples of functional group F include: primary amino, secondary amino, tertiary amino, nitrogen-containing groups formed by replacing two hydrogen atoms of a primary amino group with two protecting groups, nitrogen-containing groups formed by replacing one hydrogen atom of a secondary amino group with one protecting group, imino, nitrogen-containing heterocyclic groups (e.g., groups having heterocycles such as pyridine rings or amide rings), hydroxyl groups, oxygen-containing groups formed by replacing one hydrogen atom of a hydroxyl group with one protecting group, thiol groups, sulfur-containing groups formed by replacing one hydrogen atom of a thiol group with one protecting group, and hydrocarbyloxysilyl groups. Regarding functional group F, in terms of its high effect on improving the adhesion of highly polar substrates, or its high effect on suppressing excessive adhesion and improving the spreadability of low polar substrates, nitrogen-containing functional groups are preferred, and particularly preferred groups are those selected from the group consisting of primary amino, secondary amino, tertiary amino, and amide groups. Furthermore, from the viewpoint of ensuring that the reaction point with the modifier (post-modifier) ​​or crosslinking agent that can be used in subsequent reactions can improve heat resistance or solvent resistance, suppress residual adhesive, and prevent contamination of the bonded body caused by residue, the polymer is preferably provided with at least one of primary amino groups and secondary amino groups in part or all of the ends of polymer block A, and is particularly preferred to have at least one of multiple primary amino groups and secondary amino groups in one molecule.

[0025] <Structure of Polymer (A1)> Regarding one form of polymer (A1), in terms of being able to produce block polymers with excellent adhesive properties, and in terms of more efficiently forming network structures in reactions with crosslinking agents that can react with functional group F, thereby improving heat resistance or solvent resistance, residue suppression, and stain resistance due to low residue, radial polymers (also called star polymers) with four or more branched structures are preferred. Specifically, polymers having a structure in which four or more polymer chains containing polymer blocks A and polymer blocks B are bonded to a partial structure derived from the coupling agent are provided. As a preferred specific example of polymer (A1), block copolymers having the structure represented by the following formula (5) can be cited. (P 1)nX 1…(5) (In equation (5), P1 is a polymer chain with polymer block A and polymer block B. X1 is a partial structure derived from the coupling agent. n is an integer greater than or equal to 4.)

[0026] In equation (5), as long as P1 has polymer block A and polymer block B, there is no particular limitation on the number of blocks constituting polymer chain P1 or the configuration of each block. P1 is preferably linear.

[0027] Examples of block structures for P1 include: AB-type diblocks comprising polymer block A and polymer block B; ABA-type triblocks comprising polymer block A, polymer block B, and polymer block A; and BAB-type triblocks comprising polymer block B, polymer block A, and polymer block B. Furthermore, P1 may also have a polymer block C different from polymer blocks A and B, or may be a polymer chain with four or more blocks. Among these, P1 is preferably an AB-type diblock, an ABA-type triblock, or an ABC-type triblock, in terms of enabling the manufacture of polymers exhibiting excellent adhesive properties with fewer blocks and superior productivity. From the viewpoint of ensuring processability, forming a network structure more efficiently with a crosslinking agent, and expecting improved solvent resistance or heat resistance, n is preferably an integer from 4 to 10, more preferably from 4 to 6.

[0028] Furthermore, when the polymer chain P1 has multiple polymer blocks A, the vinyl bond content (i.e., value β) of the multiple polymer blocks A can be the same or different from each other.

[0029] One form of polymer block C is a segment having structural units derived from conjugated diene compounds and structural units derived from aromatic vinyl compounds. When the polymer (A1) further has such segments, it is preferable to optimize adhesive properties (adhesion strength, tackiness), spreadability, or vibration damping characteristics. The distribution of aromatic vinyl compounds in polymer block C is not particularly limited; for example, it can be irregular, conical, partially blocky, or any combination thereof. Among these, an irregular shape is preferred.

[0030] In polymer block C, the proportion of structural units derived from conjugated diene compounds is preferably more than 30% by mass, more preferably 50% by mass or more, and even more preferably 60% by mass or more, relative to all structural units constituting polymer block C. Furthermore, the proportion of structural units derived from conjugated diene compounds is preferably 90% by mass or less, more preferably 85% by mass or less, relative to all structural units constituting polymer block C.

[0031] Furthermore, in polymer block C, the proportion of structural units derived from aromatic vinyl compounds is preferably 10% by mass or more, more preferably 15% by mass or more, relative to all structural units constituting polymer block C. Additionally, the proportion of structural units derived from aromatic vinyl compounds is preferably less than 50% by mass, more preferably 40% by mass or less, relative to all structural units constituting polymer block C.

[0032] The proportion of structural units derived from conjugated diene compounds in polymer (A1) is preferably more than 50% by mass, more preferably 60% by mass or more, and even more preferably 70% by mass or more, relative to all structural units constituting polymer (A1). Furthermore, the proportion of structural units derived from conjugated diene compounds in polymer (A1) is preferably 98% by mass or less, more preferably 95% by mass or less. The proportion of structural units derived from conjugated diene compounds in polymer (A1) within the aforementioned range is preferred in terms of obtaining a block copolymer exhibiting good adhesive properties.

[0033] Furthermore, in the polymer (A1), the proportion of structural units derived from aromatic vinyl compounds is preferably 2% by mass or more, more preferably 5% by mass or more, relative to all structural units constituting the polymer (A1). Additionally, the proportion of structural units derived from aromatic vinyl compounds is preferably less than 50% by mass, more preferably 40% by mass or less, and even more preferably 30% by mass or less, relative to all structural units constituting the polymer (A1). When the proportion of structural units derived from aromatic vinyl compounds in the polymer (A1) is within the aforementioned range, it is preferable to prevent the polymer (A1) from becoming too stiff and to obtain a block copolymer exhibiting good adhesive properties and spreadability.

[0034] The proportion of structural units derived from aromatic vinyl compounds constituting polymer block B, relative to the total amount of structural units derived from aromatic vinyl compounds in polymer (A1), is preferably more than 50% by mass, more preferably 60% by mass or more, and even more preferably 70% by mass or more. If the proportion of structural units derived from aromatic vinyl compounds constituting polymer block B is within the aforementioned range relative to the total amount of structural units derived from aromatic vinyl compounds in polymer (A1), then a polymer with high adhesion strength to polar resin substrates can be obtained, which is preferable.

[0035] The proportion of polymer block B relative to the total mass percentage (100% by mass) of polymer block A and polymer block B is preferably 2% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more. Furthermore, the proportion of polymer block B relative to the total mass percentage of polymer block A and polymer block B is preferably less than 50% by mass, more preferably 40% by mass or less, and even more preferably 35% by mass or less. Setting the proportion of polymer block B to 2% by mass or more can moderately increase the glass transition temperature (Tg) of the polymer (Al), and can evenly improve low-adhesion reinforcement and spreadability. Furthermore, setting the proportion of polymer block B to less than 50% by mass is preferable in terms of sufficiently ensuring the adhesive properties and mechanical properties of the polymer (Al).

[0036] Furthermore, when polymer (A1) has multiple polymer blocks A or B within a single molecule, the ratio of polymer block B relative to the total amount of polymer blocks A and B represents the proportion of polymer block B (the total amount in the case of multiple polymer blocks B) relative to the total amount of all polymer blocks A and B in polymer (A1). The ratio of polymer block B relative to the total amount of polymer blocks A and B can be calculated based on the amount of monomers loaded during polymerization.

[0037] <Preparation of Block Copolymers> [A] There are no particular limitations on the method for manufacturing block copolymers. As the polymerization method used, any one of solution polymerization, gas-phase polymerization, and monolithic polymerization can be used, with solution polymerization being particularly preferred. Furthermore, as the polymerization form, either batch polymerization or continuous polymerization can be used. In the case of using solution polymerization, as a specific example of a polymerization method, the monomers are polymerized in an organic solvent in the presence of a polymerization initiator and, if necessary, a vinyl content modifier (randomizer) to produce a polymer chain P1 having polymer blocks A and B (polymerization step). Subsequently, a coupling agent is added to perform a coupling reaction (coupling step), followed by a hydrogenation reaction (hydrogenation step).

[0038] (Aggregation Step) As polymerization initiators, metal compounds containing alkali metals or alkaline earth metals can be used. Among these, compounds containing alkali metals are preferred. Specific examples of metal compounds include: alkyl lithiums such as methyl lithium, ethyl lithium, n-propyl lithium, n-butyl lithium, sec-butyl lithium, and tert-butyl lithium; 1,4-dilithiobutane, phenyl lithium, lithium stilbene, naphthyl lithium, 1,3-bis(1-lithium-1,3-dimethylpentyl)benzene, 1,3-phenylenebis(3-methyl-1-phenylpentyl)dilithium, sodium naphthyl, potassium naphthyl, and potassium ethoxylate. Among these, lithium compounds are preferred.

[0039] Alternatively, the metal compound used as the polymerization initiator can also be a metal amide compound containing an alkali metal or alkaline earth metal. By carrying out polymerization for obtaining [A] block copolymers in the presence of a metal amide compound, amino groups can be introduced into the polymerization initiation ends of the block copolymer (more specifically, the free end portions of the branched polymer). Furthermore, [A] block copolymers obtained by polymerization in the presence of a metal amide compound exhibit excellent adhesion.

[0040] The preferred metal amide compound is a compound obtained by mixing a lithium compound (e.g., alkyllithium) with a compound having a nitrogen atom (hereinafter also referred to as an "initiator-end modifier"). The initiator-end modifier is preferably a secondary amine compound, and specific examples include: dimethylamine, diethylamine, dipropylamine, dibutylamine, dodecylmethyleneimine, N,N'-dimethyl-N'-trimethylsilyl-1,6-diaminohexane, guanidine, pyrrolidine, hexamethyleneimine, heptamethylimine, dicyclohexylamine, N-methylbenzylamine, di-(2-ethylhexyl)amine, diallylamine, morpholine, N-(trimethylsilyl)pirazine, N-(tert-butyldimethylsilyl)-4-pirazine, 1,3-di-trimethylsilyl-1,3,5-triazacyclohexane, etc. Among these, compounds having a group having at least one of a primary amino group and a secondary amino group protected by a silyl compound or the like, are preferably used to improve reactivity with post-modifiers (such as maleic anhydride) or cross-linking agents (such as polyfunctional epoxy compounds) for the purpose of improving reactivity with post-modifiers (such as maleic anhydride) or cross-linking agents (such as polyfunctional epoxy compounds).

[0041] Furthermore, when polymerization is carried out in the presence of a metalloamine compound, the metalloamine compound can also be prepared by pre-mixing a lithium compound and an initiator-end modifier, and then added to the polymerization system to carry out polymerization. Alternatively, the metalloamine compound can be prepared by adding a lithium compound and an initiator-end modifier to the polymerization system and mixing them in the polymerization system to carry out polymerization. The amount of polymerization initiator used (the total amount when using two or more) is preferably 0.01 mmol to 20 mmol, more preferably 0.05 mmol to 15 mmol, relative to 100 g of monomer used in the synthesis of the polymer.

[0042] Vinyl content modifiers are used to adjust the vinyl bond content in polymers. Examples of vinyl content modifiers include: dimethoxybenzene, tetrahydrofuran, dimethoxyethane, diethylene glycol dibutyl ether, diethylene glycol dimethyl ether, 2,2-di(tetrahydrofuranyl)propane, 2-(2-ethoxyethoxy)-2-methylpropane, triethylamine, pyridine, N-methylmorpholine, and tetramethylethylenediamine. One vinyl content modifier can be used alone, or two or more can be used in combination.

[0043] As an organic solvent used in polymerization, any organic solvent that is inert in the reaction can be used, such as aliphatic hydrocarbons, alicyclic hydrocarbons, and aromatic hydrocarbons. Among these, hydrocarbons with 3 to 8 carbon atoms are preferred. Specific examples include: propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, cyclohexane, propylene, 1-butene, isobutene, trans-2-butene, cis-2-butene, 1-hexene, 2-hexene, benzene, toluene, xylene, ethylbenzene, heptane, cyclopentane, methylcyclopentane, methylcyclohexane, 1-pentene, 2-pentene, cyclohexene, etc. Furthermore, one or more organic solvents can be used alone or in combination as organic solvents.

[0044] In the case of solution polymerization, from the viewpoint of maintaining a balance between productivity and ease of polymerization control, the monomer concentration in the reaction solvent is preferably 5% to 50% by mass, more preferably 10% to 30% by mass. The polymerization temperature is preferably -30°C to 150°C. Regarding polymerization, the temperature can be kept constant, or it can be carried out at a rising temperature without heat removal. Furthermore, the polymerization reaction is preferably carried out at a pressure sufficient to substantially maintain the monomer in a liquid phase. This pressure can be obtained by pressurizing the reactor using a gas that is inert for the polymerization reaction, etc.

[0045] The method for preparing block copolymers from the reaction products (more specifically, chain polymers) obtained through the polymerization reaction can be any method. In manufacturing a block copolymer having polymer block A and polymer block B, from a productive point of view, firstly, monomers are polymerized in the presence of a polymerization initiator, thereby producing one of the segments of polymer block A and polymer block B (hereinafter also referred to as the "first segment"). Then, monomers are polymerized in the presence of the first segment, thereby producing another segment (hereinafter also referred to as the "second segment"). At this time, a metalloamine compound is used as the polymerization initiator, thereby obtaining a block copolymer with a functional group F introduced at the polymerization initiation end of the first segment. After the polymerization of the second segment, monomers are added as needed for further polymerization, thereby producing a polymer comprising the first segment, the second segment, and the third segment. The third segment can be either polymer block A or polymer block B, or it can be polymer block C.

[0046] The chain polymer obtained through this step (i.e., polymer chain P1) is preferably composed of polymer block A as the first segment and polymer block B as the second segment. In this case, the adhesive properties (especially adhesion strength and tack) of the [A] block copolymer can be improved. From the viewpoint of further improving the adhesive properties, polymer chain P1 is preferably a triblock copolymer comprising polymer block A-polymer block B-polymer block A or polymer block A-polymer block B-polymer block C. The boundaries of each polymer block may not be clearly distinguished. Furthermore, for convenience, the second polymer block A observed from the polymerization initiation end will sometimes be referred to as "polymer block A'".

[0047] (Coupling Steps) Subsequently, the block copolymer obtained through the polymerization step (i.e., the polymer chain P1 constituting polymer (A1)) is reacted with a coupling agent. There are no particular limitations on the coupling agent used in the manufacture of polymer (A1), and any known coupling agent may be used. Preferably, the coupling agent is a multifunctional coupling agent having four or more reaction sites with the active ends of the block copolymer obtained through the polymerization step.

[0048] Specific examples of coupling agents include: tetrachlorosilane, tetramethoxysilane, tetrachlorogermanium, tetrachlorotin, bis(trichlorosilyl)ethane, etc.

[0049] Alternatively, as a coupling agent, a compound having a functional group F comprising at least one element selected from the group consisting of nitrogen, silicon, oxygen, and sulfur, and having four or more reaction sites with the polymer chain obtained by the polymerization step (hereinafter also referred to as "end-modifier") may be used. Furthermore, specific examples of the functional group F possessed by the end-modifier can be the same as those of the specific examples of the functional group F described in the polymerization step.

[0050] Specific examples of such end-modifiers include nitrogen-containing alkoxysilane compounds disclosed in Japanese Patent Application Publication No. 2014-177519, Japanese Patent Application Publication No. 2016-079217, and International Publication No. 2017 / 221943; and glycidyl-containing polysiloxanes disclosed in International Publication No. 2017 / 090421. Among these, multifunctional coupling agents having nitrogen-containing functional groups are preferably used. Using nitrogen-containing multifunctional coupling agents is preferable in that it allows for the production of block copolymers with improved and more balanced inhibition of high adhesion and tackiness.

[0051] The reaction between the block copolymer obtained through the polymerization step and the coupling agent is preferably carried out as a solution reaction. From the viewpoint of sufficiently improving adhesion and spreadability, the proportion of coupling agent used (the total amount when using two or more) is preferably 0.01 mol or more, more preferably 0.05 mol or more, relative to 1 mol of the metal atoms participating in polymerization of the polymerization initiator. Furthermore, from the viewpoint of suppressing a decrease in molding processability and maintaining sufficiently high adhesion strength, the proportion of coupling agent used is preferably less than 2.0 mol, more preferably less than 1.5 mol, relative to 1 mol of the metal atoms participating in polymerization of the polymerization initiator. Moreover, one type of coupling agent can be used alone, or two or more types can be used in combination.

[0052] The reaction temperature is typically the same as that of the polymerization reaction, preferably set to -30°C to 150°C. If the reaction temperature is too low, the viscosity of the coupled polymer tends to increase; if the reaction temperature is too high, the polymerization ends are prone to deactivation. The reaction time is preferably 1 minute to 5 hours, more preferably 2 minutes to 1 hour.

[0053] From the viewpoint that the coupling reaction used to obtain the [A] block copolymer can improve the adhesion, inhibition of adhesion enhancement, and spreading properties of the [A] block copolymer, or that it can efficiently form a network structure when reacting with a crosslinking agent, the coupling rate is preferably 30% or more, more preferably 35% or more, further preferably 50% or more, and even more preferably 65% ​​or more. Furthermore, from the viewpoint of obtaining a polymer with high flowability and good molding processability, the coupling rate is preferably 98% or less, more preferably 95% or less. In addition, in this specification, "coupling rate" refers to the proportion of polymers bonded by the coupling agent in the polymer used in the reaction with the coupling agent (i.e., the polymer chain P1 constituting this polymer). The coupling rate can be calculated from the peak area ratio of a GPC curve obtained using gel permeation chromatography (GPC).

[0054] (Hydrogenation step) In this step, the block copolymer obtained through the coupling step is hydrogenated. Regarding the method and conditions of the hydrogenation reaction, any method and conditions can be used as long as the block copolymer with the desired hydrogenation rate can be obtained. Specific examples of hydrogenation methods include: methods using a catalyst with a titanium-based organometallic compound as the main component as the hydrogenation catalyst; methods using catalysts containing organometallic compounds such as iron, nickel, and cobalt, as well as alkylaluminum; methods using organic complexes of organometallic compounds such as ruthenium and rhodium; and methods using catalysts with metals such as palladium, platinum, ruthenium, cobalt, and nickel supported on supports such as carbon, silicon dioxide, and alumina. Among various methods, hydrogenation under mild conditions of low pressure and low temperature using only an organometallic compound of titanium, or using a homogeneous catalyst containing an organometallic compound of titanium and organometallic compounds of lithium, magnesium, and aluminum (for example, see Japanese Patent Publication No. 63-4841 and Japanese Patent Publication No. 1-37970) is preferred in industrial applications. In addition, it is also preferred to have high selectivity for hydrogenation of the double bond of butadiene.

[0055] The hydrogenation of block copolymers is preferably carried out using a solvent that is inert to the catalyst and can dissolve the block copolymer. Preferred solvents include individual aliphatic hydrocarbons (e.g., n-pentane, n-hexane, n-octane); alicyclic hydrocarbons (e.g., cyclohexane, cycloheptane); aromatic hydrocarbons (e.g., benzene, toluene); and ethers (e.g., diethyl ether, tetrahydrofuran) or mixtures thereof as main components.

[0056] Hydrogenation reactions are generally carried out by maintaining the block polymer at a specified temperature in a hydrogen or inert environment, adding a hydrogenation catalyst with or without stirring, then introducing hydrogen and pressurizing it to a specified pressure. An inert environment refers to an environment that does not react with the participants in the hydrogenation reaction; examples include helium, neon, and argon. There is a concern that the presence of air or oxygen may oxidize the catalyst, leading to catalyst deactivation. Additionally, there is a concern that the presence of nitrogen may act as a catalyst poison during the hydrogenation reaction, reducing hydrogenation activity. Therefore, a hydrogenation reactor with a hydrogen-only environment is preferred.

[0057] The hydrogenation process for obtaining hydrogenated block copolymers can be carried out using batch processes, continuous processes, or combinations thereof. When using a diaryl terephthalocene compound as a hydrogenation catalyst, it can be added directly to the reaction solution alone or in the form of a solution in an inert organic solvent. The amount of catalyst added is, for example, 0.02 mmol to 20 mmol per 100 g of the block copolymer before hydrogenation.

[0058] The hydrogenation rate of the [A] block copolymer is 75% or higher. If the hydrogenation rate of the [A] block copolymer is less than 75%, there is a tendency for reduced processability due to gelation, or for residue to be easily generated when peeled from the bonded body. From the viewpoint of improving processability and reducing residue, the hydrogenation rate of the [A] block copolymer is preferably 80% or higher, more preferably 83% or higher, more preferably 85% or higher, even more preferably 90% or higher, and particularly preferably 95% or higher. In addition, the hydrogenation rate of the [A] block copolymer is, for example, 99% or lower.

[0059] Furthermore, the value α represented by the formula (i) corresponds to the hydrogenation rate of the polymer. For example, when α = 0.75, the hydrogenation rate of the polymer is 75%. The hydrogenation rate of the polymer and α can be adjusted, for example, by adjusting the hydrogenation reaction time or controlling the cumulative amount of hydrogen to be supplied. In this specification, the hydrogenation rate is a value measured using a 1H-NMR apparatus.

[0060] After hydrogenation, catalyst residue is removed as needed, or phenolic or amine-based anti-aging agents are added. Subsequently, the hydrogenated conjugated diene polymer (i.e., [A] block copolymer) is separated from the polymer solution. Polymer separation can be achieved, for example, by adding acetone or alcohol to the polymer solution to precipitate it, or by distilling the polymer solution in hot water while stirring to remove the solvent.

[0061] (Post-modification steps) The hydrogenated block polymer can be used directly for the desired application, or it can be further modified (post-modification step). This modification is preferred in terms of further improving the polymer's adhesion, inhibition of increased adhesion, and spreadability. In particular, by introducing a primary or secondary amine into the terminal polymer through the modification process, the modification rate of the modifier in the post-modification step (hereinafter also referred to as "post-modifier") is increased, and the formation of post-modifier residues can be suppressed. Therefore, this is preferred in terms of suppressing substrate contamination caused by re-peeling or the diffusion of contaminating components caused by permanent adhesion into the substrate.

[0062] For [A] block copolymers, the weight-average molecular weight (Mw) of polystyrene, as determined by gel permeation chromatography (GPC), is preferably 5.0 × 10⁴ to 7.0 × 10⁵. If Mw is 5.0 × 10⁴ or higher, the mechanical properties are excellent, and it is less likely to leave residue when peeled from the substrate, resulting in high holding power and reduced misalignment between the substrate and the adhesive. Furthermore, if Mw is 7.0 × 10⁵ or lower, the flowability of the [A] block copolymer is sufficiently ensured, leading to better molding processability. The Mw of the [A] block copolymer is more preferably 7.0 × 10⁴ or higher, and even more preferably 1.0 × 10⁵ or higher. Furthermore, the Mw of the [A] block copolymer is more preferably 6.5 × 10⁵ or lower. In addition, the weight-average molecular weight (Mw) of the [A] block copolymer mentioned here is a value obtained from the total peak of the GPC curve measured by GPC before hydrogenation. Hereinafter, it is also referred to as "total weight-average molecular weight".

[0063] Furthermore, for the [A] block copolymer, the peak molecular weight (hereinafter also referred to as "1st peak weight average molecular weight") of the lowest molecular weight peak as determined by GPC is preferably in the range of 1.2 × 10⁴ to 2.2 × 10⁵. If the 1st peak weight average molecular weight is within this range, it is preferable to obtain an adhesive with a balance between adhesion strength and processability, good tack, and minimal residue generation. The 1st peak weight average molecular weight of the [A] block copolymer is more preferably 2.0 × 10⁴ or higher, and even more preferably 3.0 × 10⁴ or higher. Furthermore, for better processability, the 1st peak weight average molecular weight is more preferably 2.0 × 10⁵ or lower, and even more preferably 1.9 × 10⁵ or lower. Moreover, the 1st peak weight average molecular weight is a value obtained from the GPC curve measured by GPC before hydrogenation.

[0064] For the [A] block copolymer, the melt flow rate (MFR), measured at 230°C and a load of 21.2 N, is preferably 0.1 g / 10 min to 100 g / 10 min. In the adhesive film manufacturing step, when the resin constituting the substrate layer and the [A] block copolymer constituting the adhesive layer are co-extruded, keeping the MFR within this range improves processability. The MFR of the [A] block copolymer is more preferably 0.3 g / 10 min or more, and even more preferably 0.5 g / 10 min or more. Furthermore, the MFR of the [A] block copolymer is more preferably 50 g / 10 min or less, and even more preferably 30 g / 10 min or less.

[0065] The [A] block copolymer obtained through the above steps comprises a polymer (A1) with a multi-branched structure having four or more polymer chains. Typically, the polymer (A1) has a structure in which four or more polymer chains are bonded to a portion of the structure derived from the coupling agent. In terms of the ability to evenly improve various properties such as adhesive properties (adhesion strength, tackiness, low-adhesion reinforcement), molding processability, spreadability, and minimal residue formation, the coupling agent is preferably a nitrogen-containing functional group.

[0066] [A] The block copolymer is preferably a polymer (A1) and a linear polymer (A2). More specifically, polymer (A2) is the polymer obtained by the polymerization step and is a hydride of the unreacted polymer in the block copolymer before coupling, which was not supplied for reaction with the coupling agent. In terms of improving adhesion strength and reducing spreading force, polymer (A2) preferably has a primary, secondary, or tertiary amino group at one of its terminal portions. Such terminally modified linear polymers can be obtained by using a metalloamine compound as a polymerization initiator in the polymerization step.

[0067] When the amount of [A] block copolymer is set to 100% by mass, the proportion of polymer (A1) in the [A] block copolymer is 10% by mass or more. If the proportion of polymer (A1) relative to the [A] block copolymer is less than 10% by mass, the bonding strength and low-adhesion reinforcement are insufficient, and the adhesive performance deteriorates. In addition, there is a tendency for the spreadability to deteriorate, or for residue to be easily generated when peeled from the bonded body, and there is a tendency for it to be difficult to form a network efficiently when used with a crosslinking agent, thus failing to adequately ensure heat resistance or solvent resistance. The proportion of polymer (A1) in the [A] block copolymer is preferably 20% by mass or more, more preferably 35% by mass or more, more preferably 50% by mass or more, and even more preferably 60% by mass or more. In addition, the proportion of polymer (A1) in the [A] block copolymer is preferably 90% by mass or less, more preferably 80% by mass or less. If the proportion of polymer (A1) in the [A] block copolymer is 90% by mass or less, it is preferable in terms of improving adhesion.

[0068] Furthermore, the proportion of polymer (A1) in the [A] block copolymer can be calculated by separating the components from the waveform of the coupled polymer in a determination chart obtained using gel permeation chromatography (GPC).

[0069] Furthermore, in the [A] block copolymer, the proportion of polymer (A1) relative to the total amount (100% by mass) of polymer (A1) and polymer (A2) is preferably 10% by mass or more, preferably 20% by mass or more, more preferably 35% by mass or more, further preferably 50% by mass or more, and even more preferably 60% by mass or more. Additionally, the proportion of polymer (A1) relative to the total amount of polymer (A1) and polymer (A2) is preferably 90% by mass or less, more preferably 80% by mass or less.

[0070] Adhesives and Adhesive Films [A] block copolymers possess excellent adhesive properties, making them suitable for use as adhesives. Adhesives obtained using [A] block copolymers (hereinafter also referred to as "this adhesive") may contain only [A] block copolymers, or may further contain components different from [A] block copolymers (hereinafter also referred to as "other components"). Examples of other components include adhesive-improving agents. By incorporating adhesive-improving agents into this adhesive, the initial tack of the adhesive can be improved.

[0071] As adhesive binders, for example, petroleum-based resins (e.g., aliphatic copolymers, aromatic copolymers, aliphatic-aromatic copolymers, alicyclic copolymers, etc.), coumarone-indene resins, terpene resins, terpene-phenol resins, rosin resins, (alkyl)phenol resins, xylene resins, or hydrides of these, etc., commonly used adhesive binders in adhesive applications, can be used alone or in combination with two or more.

[0072] In addition to the components mentioned above, other components may include, for example, polyolefin resins, antioxidants, ultraviolet absorbers, colorants, light stabilizers, thermal polymerization inhibitors, defoamers, leveling agents, antistatic agents, surfactants, preservation stabilizers, anti-aging agents, flame retardants, and various fillers. In this adhesive, the proportions of other components can be appropriately set according to each component without impairing the effects of this disclosure.

[0073] Furthermore, the hydrogenated block polymer can be crosslinked by applying shear deformation to the composition containing the hydrogenated block polymer and the crosslinking agent simultaneously. By forming a crosslinked structure in the hydrogenated block copolymer, further improvements in solvent resistance or mechanical strength can be achieved. As the crosslinking agent, a compound having two or more functional groups that can react with functional group F is preferably used. Examples of such crosslinking agents include, in addition to isocyanate-based crosslinking agents, epoxy-based crosslinking agents, aziridine-based crosslinking agents, melamine-based crosslinking agents, aldehyde-based crosslinking agents, amine-based crosslinking agents, chelate-based crosslinking agents, and carbodiimide-based crosslinking agents, compounds containing hydroxyl groups, acid compounds, acid anhydrides, and free radical generators.

[0074] Examples of isocyanate-based crosslinking agents include: toluene diisocyanate and 2,6-toluene diisocyanate; phenyl dimethyl diisocyanate and 1,3-phenylenediamine diisocyanate; diphenylmethane-based crosslinking agents such as diphenylmethane-4,4-diisocyanate; aromatic isocyanate-based crosslinking agents such as naphthalene diisocyanate and 1,5-naphthalene diisocyanate; isophorone diisocyanate, 1,4-cyclohexane diisocyanate, etc. Hexane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, methylcyclohexane diisocyanate, isopropylidene dicyclohexyl-4,4'-diisocyanate, 1,3-diisocyanomethylcyclohexane, norbornene diisocyanate and other alicyclic isocyanate crosslinking agents; hexamethylene diisocyanate, trimethylhexamethylene diisocyanate and other aliphatic isocyanate crosslinking agents; and adducts, biuret bodies, isocyanurate bodies, etc. of the aforementioned isocyanate compounds.

[0075] In addition, examples of epoxy-based crosslinking agents include: bisphenol A-epimyl chloride type epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerol diglycidyl ether, glycerol triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl erythritol, diglycerol polyglycidyl ether, etc.

[0076] Examples of aziridine-based crosslinking agents include: tetramethylolpropane-tri-β-aziridine propionate, trimethylolpropane-tri-β-aziridine propionate, N,N'-diphenylmethane-4,4'-bis(1-aziridine carboxylated amide), and N,N'-hexamethylene-1,6-bis(1-aziridine carboxylated amide).

[0077] Examples of melamine-based crosslinking agents include: hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, hexabutoxymethyl melamine, hexapentoxymethyl melamine, hexahexoxymethyl melamine, and melamine resin.

[0078] In addition, examples of aldehyde-based crosslinking agents include glyoxal, malondialdehyde, succinaldehyde, maleic anhydride, glutaraldehyde, formaldehyde, acetaldehyde, benzaldehyde, etc.

[0079] Examples of amine-based crosslinking agents include: hexamethylenediamine, triethyldiamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethyltetramine, isophoronediamine, amino resins, polyamides, etc.

[0080] Examples of crosslinking agents for the metal chelate system include acetoacetone or acetoacetyl ester coordination compounds of multivalent metals such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, and zirconium.

[0081] Examples of carbodiimide-based crosslinking agents include, for example, multifunctional carbodiimide compounds or polymeric carbodiimide compounds.

[0082] Examples of hydroxyl-containing compounds include, for example, polyether polyols or polyester polyols, acrylic polyols, polybutadiene polyols, and polyisoprene polyols.

[0083] Examples of carboxyl-containing multifunctional crosslinking agents include: σ-phthalic acid, isophthalic acid, terephthalic acid, 1,4-dimethylterephthalic acid, 1,3-dimethylisophthalic acid, 5-sulfon-1,3-dimethylisophthalic acid, 4,4-biphenyl dicarboxylic acid, 1,4-naphthalenediic acid, 2,6-naphthalenediic acid, norbornene dicarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, or phenylindendicarboxylic acid, etc., aromatic dicarboxylic acids; phthalic anhydride, 1,8-naphthalenedi... Aromatic dicarboxylic anhydrides such as carboxylic anhydrides or 2,3-naphthalenedicarboxylic anhydride; alicyclic dicarboxylic acids such as hexahydrophthalic acid; alicyclic dicarboxylic anhydrides such as hexahydrophthalic anhydride, 3-methyl-hexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride or 1,2-cyclohexanedicarboxylic anhydride; and aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, octanoic acid, maleic acid, chloromaleic acid, fumaric acid, dodecanoic acid, pimelic acid, citraconic acid, glutaric acid or itaconic acid.

[0084] Examples of such acid anhydrides include: pyromellitic anhydride, benzophenone tetracarboxylic anhydride, biphenyl tetracarboxylic anhydride, oxydiphthalic anhydride, diphenyl sulfide tetracarboxylic anhydride, diphenyl sulfide tetracarboxylic anhydride, butane tetracarboxylic anhydride, perylene tetracarboxylic anhydride, or naphthalene tetracarboxylic anhydride.

[0085] The free radical generator is used to generate free radicals by heating or irradiation with light such as ultraviolet light during the fabrication of the adhesive layer that constitutes part of the adhesive film. Free radicals are generated, causing the polymer to crosslink. Preferably, the free radical generator is a photoradioactive free radical generator that generates free radicals by irradiation with light such as ultraviolet light. Specific examples of photoradioactive free radical generators include: hydroxy ketones, benzyl dimethyl ketals, amino ketones, phosphine oxides, benzophenones, etc. These photoradioactive free radical generators can be used alone or in combination of two or more.

[0086] As a free radical generator, it can be an oligomeric photoradical generator. An oligomeric photoradical generator is a low molecular weight polymer of a monomer having functional groups that can generate free radicals when exposed to light such as ultraviolet light. This type of oligomeric photoradical generator is preferred because it has multiple free radical generation sites within a single molecule, making it less susceptible to crosslinking hindrance caused by oxygen, allowing for minimal crosslinking treatment, and preventing dispersion and extraction from the polymer even when coated onto a substrate in a solvent-free hot-melt state.

[0087] Specific examples of oligomeric photoradical generators include: oligomers synthesized from benzophenone acrylate (trade name "Ebecryl P36" manufactured by UCB); oligomers synthesized from the reaction product of the primary hydroxyl group of 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propane-1-one (trade name "Irgacure 2959" manufactured by BASF) and ethyl 2-isocyanate of methacrylate; and 2-hydroxy-2-methyl-[4-(1-methylvinyl)phenyl]propanol oligomers (trade name "Esacure KIP150" manufactured by Lamberti). The molecular weight of these oligomeric photoradical generators is preferably around 50,000 or less.

[0088] Furthermore, one type of crosslinking agent can be used alone, or two or more can be used in combination. The amount of crosslinking agent used can be determined according to the desired performance of the final target composition. The amount of crosslinking agent used is typically 0.1 to 20 parts by mass relative to 100 parts by mass of the polymer, preferably 0.2 to 10 parts by mass. The reaction between the polymer and the crosslinking agent can be carried out in the presence of a curing catalyst as needed.

[0089] This adhesive can be used for a variety of applications. Specifically, it can be used as an adhesive tape, adhesive label, adhesive sheet, assembly, building material protective film, resin board protective film, automotive protective film, protective film for optical components (e.g., for liquid crystal displays and various displays, light guide plates), interlayer film for laminated glass, and other adhesive films. In particular, this adhesive is suitable for use as a surface protective film for optical applications (e.g., surface protective film for optical films).

[0090] This polymer possesses excellent properties such as initial tack or low adhesion enhancement, spreadability, residual adhesive suppression, and solvent resistance, making it suitable for a wide range of applications. Specifically, in addition to serving as an adhesive layer for surface protective films, an adhesive layer for bonding films in structures, and a modifier for resin compositions, it can also be used as a molded body. Furthermore, this polymer exhibits excellent vibration damping properties, making it suitable for various applications such as vibration damping materials, vibration damping films, and vibration damping sheets.

[0091] Furthermore, according to this disclosure, a laminate having an X layer containing the present polymer and a Y layer laminated on at least one side of the X layer is also provided. Such a laminate is preferably, for example, laminated glass. Specifically, by using the X layer as an interlayer for laminated glass and the Y layer as a glass layer, and then laminating these together to produce laminated glass, excellent vibration damping and excellent sound insulation are expected. In addition to a glass layer, the Y layer can be suitably selected according to various applications. For example, a laminate having a layer containing a thermoplastic resin other than the present polymer as the Y layer can be cited. Examples of such thermoplastic resins include polyvinyl acetal resin, ionomer, ethylene-vinyl acetate copolymer, urethane resin, and polyamide resin.

[0092] Other uses of this polymer include, for example, the following. (1) Pellets, packaging materials, sound-absorbing materials, sound-insulating materials, sealing rubber, shoe sole materials, floor materials, weatherstrip, floor mat, front bulkhead insulator, roof lining, door panels, engine cover, door hole seal, fender liner, etc. (2) Various automotive products: such as thermostat housings, radiator boxes, radiator hoses, water outlets, water pump housings, rear joints, and other cooling parts; intercooler boxes, intercooler housings, turbine guides, exhaust gas recirculation (EGR) cooler boxes, resonators, throttle bodies, intake manifolds, exhaust pipes, and other intake and exhaust system parts; fuel delivery pipes, gasoline cans, quick couplings, canisters, pump modules, fuel lines, oil filters, lock nuts, sealing materials, and other fuel system parts; mount brackets, torque rods, cylinder head covers, and other structural parts; bearing retainers, gear tensioners, headlight actuator gears, and HVAC components. Drive system parts such as gears, sliding door rollers, and clutch peripheral parts (conditioning, HVAC); braking system parts such as air brake pipes; wiring harness connectors, motor parts, sensors, acrylonitrile-butadiene-styrene (ABS) spools, combination switches, vehicle switches, electronic control unit (ECU) boxes, and other vehicle electrical components in the engine compartment; sliding door dampers, rearview mirror mounts, rearview mirror brackets, interior mirror mounts, roof longitudinal beams, engine mounting brackets, air purifier intake pipes, door checkers, plastic chains, emblems, clamps, circuit breaker covers, cup holders, airbags, fenders, spoilers, radiator supports, radiator grilles, vents, air intakes, hood protrusions, rear doors, fuel delivery modules, floor mats, instrument panels, dashboards, and front bulkhead insulators. Insulators, sealing rubber, sealing strips and other interior and exterior decorative parts, tires, etc.

[0093] (3) Various products in the home appliance field: such as televisions, Blu-ray recorders or hard disc drive (HDD) recorders and other video recorders, projectors, game consoles, digital cameras, home video cameras, antennas, speakers, electronic dictionaries, integrated circuit (IC) video recorders, fax machines, photocopiers, telephones, doorbell telephones, electric rice cookers, microwave ovens, ovens, refrigerators, dishwashers, dish dryers, induction cookers, heating plates, vacuum cleaners, washing machines, chargers, sewing machines, irons, dryers, electric bicycles, air purifiers, water purifiers, electric toothbrushes, lighting fixtures, air conditioners, outdoor units of air conditioners, dehumidifiers, humidifiers and other electrical products, including sealing materials, adhesives, gaskets, O-rings, tapes, sound insulation materials, etc.

[0094] In addition, this polymer can also be used as a modifier to improve the toughness or impact resistance of thermoplastic resins. Examples of thermoplastic resins for which this polymer is formulated as a modifier include: polypropylene, polyethylene, polystyrene, polycarbonate, polyester, polyarylene, polyarylene ether, polyarylene sulfide, polyamide, polyimide, ABS resin, etc. [Example]

[0095] The following detailed description is based on embodiments, but the present invention is not limited to these embodiments. Furthermore, unless otherwise specified, "parts" and "%" in the embodiments and comparative examples are quality standards.

[0096] 1. Methods for determining physical properties The methods for determining various physical properties of polymers are described below. [Vinyl bond content (mol%)]: Calculated using the unhydrogenated polymer by 1H-NMR spectroscopy measured with a 500 MHz apparatus. [1st peak weight average molecular weight]: The holding time of the longest-holding peak in the GPC curve obtained using a gel permeation chromatography (GPC) instrument (HLC-8120GPC (manufactured by Tosoh Corporation)) was calculated using polystyrene. (GPC conditions) Tube String: Two tubes, product name "GMHXL" (manufactured by Tosoh Corporation). Column temperature: 40℃ Mobile phase: Tetrahydrofuran Flow rate: 1.0 ml / min Sample concentration: 10 mg / 20 ml [Total weight average molecular weight]: Calculated from the GPC curve obtained using a gel permeation chromatography (GPC) instrument (HLC-8120GPC (product name (manufactured by Tosoh Corporation))) and converted using polystyrene. [Coupling rate]: Calculated from the peak area ratio of the GPC curve obtained using a gel permeation chromatography (GPC) instrument (HLC-8120GPC (product name (manufactured by Tosoh Corporation))). [Hydrogenation rate]: Calculated using tetrachloroethylene as solvent and measured by 1H-NMR spectra using a 100 MHz apparatus. [Mel flow rate (MFR)]: Measured according to Japanese Industrial Standards (JIS) K7210, at 230°C and a load of 21.2 N.

[0097] 2. Manufacturing of block copolymers [Example 1]: Manufacturing of polymer (A-1) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.11 parts of guanidine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The resulting polymer is a block copolymer comprising polymer block A, polymer block B, and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B contains structural units derived from styrene, and polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 110,000, a total weight-average molecular weight of 340,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-1) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 0.3 g / 10 min. The various physical properties of the obtained polymer (A-1) are shown in Table 1.

[0098] [Example 2]: Manufacturing of polymer (A-2) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.15 parts of guanidine, and 0.16 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.08 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The resulting polymer is a block copolymer comprising polymer block A, polymer block B, and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 71 mol%. Polymer block B contains structural units derived from styrene, and polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 72 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 80,000, a total weight-average molecular weight of 260,000, and a coupling rate of 70%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-2) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 16.2 g / 10 min. The various physical properties of the obtained polymer (A-2) are shown in Table 1.

[0099] [Example 3]: Manufacturing of polymer (A-3) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.11 parts of guanidine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.07 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The resulting polymer is a block copolymer comprising polymer block A, polymer block B, and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 73 mol%. Polymer block B contains structural units derived from styrene, and polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 71 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 110,000, a total weight-average molecular weight of 380,000, and a coupling rate of 95%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-3) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 1.3 g / 10 min. The various physical properties of the obtained polymer (A-3) are shown in Table 1.

[0100] [Example 4]: Manufacturing of polymer (A-4) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.08 parts of guanidine, and 0.08 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.03 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The resulting polymer is a block copolymer comprising polymer block A, polymer block B, and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B contains structural units derived from styrene, and polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 72 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 160,000, a total weight-average molecular weight of 460,000, and a coupling rate of 73%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-4) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 0.7 g / 10 min. The various physical properties of the obtained polymer (A-4) are shown in Table 1.

[0101] [Example 5]: Manufacturing of polymer (A-5) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.25 parts of N-(tert-butyldimethylsilyl)piperazine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The resulting polymer is a block copolymer comprising polymer block A, polymer block B, and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B contains structural units derived from styrene, and polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 72 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 110,000, a total weight-average molecular weight of 340,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-5) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 2.7 g / 10 min. The various physical properties of the obtained polymer (A-5) are shown in Table 1.

[0102] [Example 6]: Manufacturing of polymer (A-6) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.08 parts of guanidine, and 0.08 parts of n-butyllithium were added. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The resulting polymer is a block copolymer comprising polymer block A, polymer block B, and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B contains structural units derived from styrene, and polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 160,000, a total weight-average molecular weight of 320,000, and a coupling rate of 35%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-6) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 2.7 g / 10 min. The various physical properties of the obtained polymer (A-6) are shown in Table 1.

[0103] [Example 7]: Manufacturing of polymer (A-7) By reducing the amount of hydrogen supplied in the hydrogenation reaction, and otherwise using the same manufacturing method as polymer (A-1), polymer (A-7) with a hydrogenation rate of 83% for the conjugated diene moiety and an MFR of 5.2 g / 10 min was obtained. The various physical properties of the obtained polymer (A-7) are shown in Table 1.

[0104] [Example 8]: Manufacturing of polymer (A-8) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, and 0.12 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.16 parts of 1,1'-(1,4-phenylene)bis(N-(3-(triethoxysilyl)propyl)methaneimine) were added, and polymerization was initiated at elevated temperature. The resulting polymer is a block copolymer comprising polymer block A, polymer block B, and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B contains structural units derived from styrene, and polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 100,000, a total weight-average molecular weight of 290,000, and a coupling rate of 70%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-8) with a hydrogenation rate of 97% for the conjugated diene moiety and an MFR of 3.6 g / 10 min. The various physical properties of the obtained polymer (A-8) are shown in Table 1.

[0105] [Example 9]: Manufacturing of polymer (A-9) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.12 parts of guanidine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.16 parts of 1,1'-(1,4-phenylene)bis(N-(3-(triethoxysilyl)propyl)methaneimine) were added, and polymerization was initiated at elevated temperature. The obtained polymer is a block copolymer having polymer block A, polymer block B, and polymer block A'. Polymer block A comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B comprises structural units derived from styrene, and polymer block A' comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 100,000, a total weight-average molecular weight of 340,000, and a coupling rate of 77%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-9) with a hydrogenation rate of 96% for the conjugated diene moiety and an MFR of 4.5 g / 10 min. The various physical properties of the obtained polymer (A-9) are shown in Table 1.

[0106] [Example 10]: Manufacturing of polymer (A-10) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 4.1 parts of tetrahydrofuran, 0.11 parts of guanidine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The obtained polymer is a block copolymer having polymer block A, polymer block B, and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 52 mol%. Polymer block B contains structural units derived from styrene, and polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 54 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 110,000, a total weight-average molecular weight of 340,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-10) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 1.3 g / 10 min. The various physical properties of the obtained polymer (A-10) are shown in Table 1.

[0107] [Example 11]: Manufacturing of polymer (A-11) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.11 parts of guanidine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 50 parts of 1,3-butadiene and 20 parts of styrene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The resulting polymer is a block copolymer comprising polymer blocks A, B, and C. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B contains structural units derived from styrene. Polymer block C contains structural units derived from both 1,3-butadiene and styrene, and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 110,000, a total weight-average molecular weight of 340,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-11) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 4.5 g / 10 min. The various physical properties of the obtained polymer (A-11) are shown in Table 2.

[0108] [Example 12]: Manufacturing of polymer (A-12) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.11 parts of guanidine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 20 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 34°C, and 60 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The obtained polymer is a block copolymer having polymer block A, polymer block B, and polymer block A'. Polymer block A comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B comprises structural units derived from styrene, and polymer block A' comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 110,000, a total weight-average molecular weight of 340,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-12) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 1.3 g / 10 min. The various physical properties of the obtained polymer (A-12) are shown in Table 2.

[0109] [Example 13]: Manufacturing of polymer (A-13) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.11 parts of guanidine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 5 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 20°C, and 85 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The obtained polymer is a block copolymer having polymer block A, polymer block B, and polymer block A'. Polymer block A comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B comprises structural units derived from styrene, and polymer block A' comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 110,000, a total weight-average molecular weight of 340,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-13) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 2.4 g / 10 min. The various physical properties of the obtained polymer (A-13) are shown in Table 2.

[0110] [Example 14]: Manufacturing of polymer (A-14) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.11 parts of guanidine, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 10 parts of styrene were added, and polymerization was carried out at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 17°C, and 90 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, followed by further polymerization at elevated temperature. The obtained polymer is a block copolymer containing polymer block B and polymer block A. Polymer block B contains structural units derived from styrene, and polymer block A contains structural units derived from 1,3-butadiene, with a vinyl bond content of 70 moles. Furthermore, the obtained block copolymer has a first-wave weight average molecular weight of 110,000, a total weight average molecular weight of 340,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-14) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 2.0 g / 10 min. The various physical properties of the obtained polymer (A-14) are shown in Table 2.

[0111] [Comparative Example 1]: Manufacturing of Polymer (A-15) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, and 0.11 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.05 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The obtained polymer is a block copolymer having polymer block A, polymer block B, and polymer block A'. Polymer block A comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B comprises structural units derived from styrene, and polymer block A' comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 120,000, a total weight-average molecular weight of 350,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-15) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 3.1 g / 10 min. The various physical properties of the obtained polymer (A-15) are shown in Table 2.

[0112] [Comparative Example 2]: Manufacturing of Polymer (A-16) In a nitrogen-purged reaction vessel, 800 parts of degassed and dehydrated cyclohexane, 0.03 parts of tetrahydrofuran, 0.14 parts of guanidine, and 0.14 parts of n-butyllithium were charged. At a polymerization initiation temperature of 70°C, 30 parts of 1,3-butadiene were added, and polymerization was carried out at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 20°C, and 70 parts of 1,3-butadiene and 16 parts of tetrahydrofuran were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.06 parts of tetrachlorosilane were added, followed by further polymerization at elevated temperature. The obtained polymer is a block copolymer having polymer block A and polymer block A'. Polymer block A contains structural units derived from 1,3-butadiene and has a vinyl bond content of 15 mol%, while polymer block A' contains structural units derived from 1,3-butadiene and has a vinyl bond content of 75 mol%. In addition, the obtained block copolymers have a first-wave peak weight-average molecular weight of 100,000, a total weight-average molecular weight of 300,000, and a coupling rate of 75%. Subsequently, 0.05 parts of diethylaluminum chloride and 0.11 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-16) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 4.2 g / 10 min. The various physical properties of the obtained polymer (A-16) are shown in Table 2.

[0113] [Comparative Example 3]: Manufacturing of Polymer (A-17) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.05 parts of guanidine, and 0.06 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.002 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The obtained polymer is a block copolymer having polymer block A, polymer block B, and polymer block A'. Polymer block A comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B comprises structural units derived from styrene, and polymer block A' comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 220,000, a total weight-average molecular weight of 270,000, and a coupling rate of 8%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-17) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 4.8 g / 10 min. The various physical properties of the obtained polymer (A-17) are shown in Table 2.

[0114] [Comparative Example 4]: Manufacturing of Polymer (A-18) By reducing the amount of hydrogen supplied in the hydrogenation reaction, and otherwise using the same manufacturing method as polymer (A-1), polymer (A-18) with a hydrogenation rate of 60% for the conjugated diene moiety and an MFR of 7.6 g / 10 min was obtained. The various physical properties of the obtained polymer (A-18) are shown in Table 2.

[0115] [Comparative Example 5]: Manufacturing of Polymer (A-19) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, 0.06 parts of guanidine, and 0.06 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 10 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 70 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.04 parts of methyldichlorosilane were added, and polymerization was initiated at elevated temperature. The obtained polymer is a block copolymer having polymer block A, polymer block B, and polymer block A'. Polymer block A comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B comprises structural units derived from styrene, and polymer block A' comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 220,000, a total weight-average molecular weight of 300,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-19) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 1.2 g / 10 min. The various physical properties of the obtained polymer (A-19) are shown in Table 2.

[0116] [Comparative Example 6]: Manufacturing of Polymer (A-20) In a nitrogen-purged reaction vessel, 550 parts of degassed and dehydrated cyclohexane, 14 parts of tetrahydrofuran, and 0.06 parts of n-butyllithium were charged. At a polymerization initiation temperature of 40°C, 20 parts of 1,3-butadiene were added, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, 12 parts of styrene were added at the same temperature, and polymerization was initiated at elevated temperature. After the polymerization conversion reached over 99%, the reaction solution was cooled to 30°C, and 68 parts of 1,3-butadiene were added, followed by further polymerization at elevated temperature. After the polymerization conversion reached over 99%, 0.03 parts of tetrachlorosilane were added, and polymerization was initiated at elevated temperature. The obtained polymer is a block copolymer having polymer block A, polymer block B, and polymer block A'. Polymer block A comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol%. Polymer block B comprises structural units derived from styrene, and polymer block A' comprises structural units derived from 1,3-butadiene and has a vinyl bond content of 70 mol. Furthermore, the obtained block copolymer has a first-wave weight-average molecular weight of 210,000, a total weight-average molecular weight of 580,000, and a coupling rate of 75%. Subsequently, 0.04 parts of diethylaluminum chloride and 0.10 parts of bis(cyclopentadienyl)furfuryloxytitanium chloride were added to the reaction vessel and stirred. The hydrogenation reaction was initiated at a hydrogen supply pressure of 0.7 MPa-gauge and a reaction temperature of 80°C. After 3.0 hours, the reaction solution was brought to atmospheric pressure at 60°C and removed from the reaction vessel. Then, 0.2 parts of 2,6-di-tert-butyl-p-cresol were added to the obtained polymer solution, stirred, and added to water. The solvent was removed by steam distillation, and the solution was dried using a hot roller heated to 110°C, thereby obtaining a polymer (A-20) with a hydrogenation rate of 98% for the conjugated diene moiety and an MFR of 0.1 g / 10 min. The various physical properties of the obtained polymer (A-20) are shown in Table 2.

[0117] 3. Manufacturing of adhesive films and evaluation of their adhesive properties Using polyethylene (manufactured by Mitsubishi Chemical Corporation, YF30) as the substrate layer and polymers (A-1) to (A-20) manufactured above as the adhesive layers, the substrate layer and adhesive layer were co-extruded into an adhesive film (Examples 1 to 14, Comparative Examples 1 to 6) using a biaxial co-extrusion apparatus including a feedblock type T-die. The substrate layer thickness was 100 μm and the adhesive layer thickness was 10 μm. The forming conditions (barrel temperature, die temperature) were set as follows: adhesive layer extrusion temperature: 150°C-220°C (hopper side-die side (°C)), substrate layer extrusion temperature: 150°C-220°C (hopper side-die side (°C)), die temperature: 220°C. Furthermore, in the manufacture of the adhesive film, as stabilizers, 0.2 parts by mass each of "Tinuvin 326" (manufactured by Ciba Specialty Chemicals) and "Adekastab 52" (manufactured by Asahi Denka Co.) were added to the block copolymer, relative to 100 parts by mass of the block copolymer. The adhesive film obtained thereby was evaluated for the following properties. The evaluation methods are described below.

[0118] [Extrusion Molding Properties] The adhesive film obtained by co-extrusion molding is evaluated visually according to the evaluation criteria of the four stages A to D shown below. (Evaluation Criteria) A: No surface roughness was detected, and no thickness unevenness was found. B: No surface roughness, but uneven thickness was confirmed. C: Melt fracture was confirmed on a portion of the surface. D: Melt fracture was confirmed across the entire surface, indicating poor formability.

[0119] [Peel strength] At a room temperature of 23°C and a relative humidity of 50%, a benchtop laminator was used to apply the adhesive films of the examples and comparative examples to stainless steel (SUS) plates (SUS mirror finish) with a surface roughness of 2.0 μm to 5.0 μm using a pressure of 5.9 × 10⁵ Pa and a speed of 30 mm / min. After being placed at a room temperature of 23°C and a relative humidity of 50% for 30 minutes, the 180-degree peel strength of these films (25 mm wide) was measured at a speed of 300 mm / min according to the method of Japanese Industrial Standards (JIS) Z 0237:2009, and this was taken as the initial peel strength. Based on the obtained initial peel strength, the peel strength was determined according to the judgment criteria of the four stages A to D below. A: Above 0.50 N / 10 mm, with extremely good peel strength. B: 0.30 N / 10 mm or more and less than 0.50 N / 10 mm, good peel strength. C: ≥0.10 N / 10 mm and <0.30 N / 10 mm, peel strength is at the permissible level. D: less than 0.10 N / 10 mm, poor peel strength.

[0120] [Low viscosity enhancement] At a room temperature of 23°C and a relative humidity of 50%, a benchtop laminator was used to attach the adhesive films of the examples and comparative examples to the surface of the same SUS board used in the peel strength evaluation, at a pressure of 5.9 × 10⁵ Pa and a speed of 30 mm / min. The adhesive films were then placed at 60°C for 30 minutes and then at 60°C for one week. Following JIS Z0237, the 180-degree peel strength of these films (25 mm wide) was measured at a speed of 300 mm / min, and these were recorded as the initial peel strength and the peel strength over time. The change ratio of the peel strength over time (adhesion enhancement ratio) was calculated based on the initial peel strength using the following formula (a). Change ratio (adhesion reinforcement ratio) = (peel strength over time / initial peel strength)...(a) Based on the obtained change ratio (adhesion enhancement ratio), the enhancement of adhesion is determined according to the following four-stage judgment criteria (A to D). A: In the range of adhesive reinforcement ratio below 1.2, the low adhesive reinforcement is extremely good. B: The adhesion reinforcement ratio is in the range of more than 1.2 and less than 1.6, indicating good low adhesion reinforcement. C: The bond strength ratio is in the range of more than 1.6 and 2.0, and low bond strength is permissible. D: The bond strength ratio exceeds 2.0, indicating poor low bond strength.

[0121] [Expandability] Under conditions of 23°C and 50% relative humidity, a benchtop laminator was used to attach the adhesive films of the examples and comparative examples onto polypropylene films at a pressure of 5.9 × 10⁵ Pa and a speed of 30 mm / min. After being placed at 23°C for 24 hours, the 180-degree peel strength of the adhesive film (25 mm wide) was measured at a speed of 15 m / min according to JIS Z 0237, and this was taken as the unfolding force. Based on the obtained unfolding force, the unfoldability was determined according to the following four-stage judgment criteria (A to D). A: Less than 0.05 N / 10 mm, with extremely good spreadability. B: ≥0.05 N / 10 mm and <0.10 N / 10 mm, good spreadability. C: ≥0.10 N / 10 mm and <0.20 N / 10 mm, the unfoldability is at the permissible level. A D value greater than 0.20 N / 10 mm may adversely affect the rewinding of the film roll, resulting in poor unfolding properties.

[0122] [Residual glue] In the evaluation of low adhesion enhancement, the surface of the SUS board after the peel strength over time is visually inspected to confirm the presence or absence of adhesive residue. Based on the presence or absence of residue, the residue is determined according to the following two-stage judgment criteria, A and B. A: No residue, good residual adhesive. B: Residue was found, which has a high degree of contamination on polar substrates, therefore the residue is undesirable.

[0123] [Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 polymer Polymer Name A-1 A-2 A-3 A-4 A-5 A-6 A-7 A-8 A-9 A-10 Segment A monomer BD BD BD BD BD BD BD BD BD BD Number of portions (parts by weight) 20 20 20 20 20 20 20 20 20 20 Vinyl bond content (mol%) 70 71 73 70 70 70 70 70 70 52 Segment B monomer ST ST ST ST ST ST ST ST ST ST Number of portions (parts by weight) 10 10 10 10 10 10 10 10 10 10 Segment A or Segment C monomer BD BD BD BD BD BD BD BD BD BD Number of portions (parts by weight) 70 70 70 70 70 70 70 70 70 70 Vinyl bond content (mol%) 70 72 71 72 72 70 70 70 70 54 Initiator end modifier R-1 R-1 R-1 R-1 R-2 R-1 R-1 none R-1 R-1 Coupling agent C-1 C-1 C-1 C-1 C-1 C-1 C-1 C-3 C-3 C-1 Molecular weight at 1st peak (×10⁴) 11 8 11 16 11 16 11 10 10 11 Total molecular weight (×10⁴) 34 26 38 46 34 32 34 29 34 34 Coupling rate (%) 75 70 95 73 75 35 75 73 77 75 Hydrogenation rate (%) 98 98 98 98 98 98 83 97 96 98 MFR_230℃21 N 3.0 16.2 1.3 0.7 2.7 4.2 5.2 3.6 4.5 1.3 The proportion (mass%) of polymer (A1) 73 67 93 71 72 32 73 71 74 72 Evaluation results Extrusion molding properties B A C C B A C B B C Peel strength B B B B B C B A A C Low adhesion reinforcement B C A A B C C B A B Expansiveness B C A A B C C B A C Residual glue A A A A A A A A A A

[0124] [Table 2] Example 11 Example 12 Example 13 Example 14 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 polymer Polymer Name A-11 A-12 A-13 A-14 A-15 A-16 A-17 A-18 A-19 A-20 Segment A monomer BD BD BD - BD BD BD BD BD BD Number of portions (parts by weight) 20 20 5 - 20 30 20 20 20 20 Vinyl bond content (mol%) 70 70 70 - 70 15 70 70 70 70 Segment B monomer ST ST ST ST ST - ST ST ST ST Number of portions (parts by weight) 10 20 10 10 10 - 10 10 10 12 Segment A or Segment C monomer BD / ST BD BD BD BD BD BD BD BD BD Number of portions (parts by weight) 50 / 20 60 85 90 70 70 70 70 70 68 Vinyl bond content (mol%) 70 70 70 70 70 75 70 70 70 70 Initiator end modifier R-1 R-1 R-1 R-1 none R-1 R-1 R-1 R-1 none Coupling agent C-1 C-1 C-1 C-1 C-1 C-1 C-1 C-1 C-2 C-1 Molecular weight at 1st peak (×10⁴) 11 11 11 11 12 10 twenty two 11 twenty two twenty one Total molecular weight (×10⁴) 34 34 34 34 35 30 27 34 30 58 Coupling rate (%) 75 75 75 75 75 75 8 75 75 75 Hydrogenation rate (%) 98 98 98 98 98 98 98 60 98 98 MFR_230℃21 N 4.5 1.3 2.4 2.0 3.1 4.2 4.8 7.6 1.2 0.1 The proportion (mass%) of polymer (A1) 73 72 73 73 73 72 7 73 73 73 Evaluation results Extrusion molding properties A C B B B C B D D D Peel strength B C C C D D D B D D Low adhesion reinforcement C B B B C B D D D C Expansiveness A B B B D B D C D D Residual glue A A A A A A B B A A

[0125] In Tables 1 and 2, the abbreviations for monomers, initiator-terminated modifiers, coupling agents, and post-modifiers refer to the following compounds. The number of monomer parts indicates the amount contained (parts by mass). ·BD:1,3-Butadiene ·ST: Styrene R-1: guanidine R-2: N-(tert-butyldimethylsilyl)pirazine C-1: Tetrachlorosilane C-2: Methyldichlorosilane •C-3:1,1'-(1,4-phenylene)bis(N-(3-(triethoxysilyl)propyl)methaneimine)

[0126] As shown in Tables 1 and 2, the adhesive films of Examples 1 to 14, which used [A] block copolymers, exhibited uniform extrusion formability, adhesion strength (peel strength), low adhesion advance, spreadability, and residual properties. In contrast, Comparative Examples 1 and 6, which did not use an initiator-end modifier during polymerization, received a rating of "D" for adhesion strength and spreadability. Furthermore, the adhesive film of Comparative Example 3, which had a lower polymer (A1) content, showed even worse low adhesion advance and residual properties, and the adhesive film of Comparative Example 5, which used a difunctional coupling agent, also exhibited poor extrusion formability and low adhesion advance. Additionally, Comparative Example 2, which did not contain styrene blocks, received a rating of "D" for adhesion strength and tack. The adhesive film of Comparative Example 4, which used a block copolymer with a hydrogenation rate reduced to 60%, showed poor extrusion formability, and its low adhesion advance and residual properties were also insufficient.

[0127] The above results clearly demonstrate that the block copolymers of the present invention exhibit balanced processability, adhesive properties, and spreadability. Furthermore, it can be confirmed that the block copolymers of the present invention are not prone to adhesive reinforcement and do not easily leave residue when peeled from the bonded substrate.

Claims

1. A block copolymer, wherein when the structural units represented by the following formula (1), the following formula (2), the following formula (3), and the following formula (4) are respectively set in the polymer in proportions of p, q, r, and s, the value α represented by the following formula (i) is 0.83 or more, the proportions being molar ratios, the block copolymer comprising 10% by mass or more of a polymer (A1) having a multi-branched structure having four or more polymer chains, the polymer chains having polymer blocks A and polymer blocks B, the polymer blocks A comprising 70% by mass or more of structural units derived from conjugated diene compounds, the polymer blocks B comprising 70% by mass or more of structural units derived from aromatic vinyl compounds, and a portion or all of the ends of the four or more polymer chains having functional groups F, the functional groups F comprising at least one element selected from the group consisting of nitrogen, silicon, oxygen, and sulfur, the functional groups F comprising at least nitrogen. α=(p+(0.5×r)) / (p+q+(0.5×r)+s)…(i).

2. The block copolymer as claimed in claim 1, comprising 20% ​​to 90% by mass of the polymer (A1).

3. The block copolymer as claimed in claim 1, comprising 50% to 80% by mass of the polymer (A1).

4. The block copolymer as described in any one of claims 1 to 3, wherein, The functional group F has at least one selected from the group consisting of primary amino, secondary amino and tertiary amino groups.

5. The block copolymer as claimed in claim 1, wherein, The functional group F is located at the end of either polymer block A or polymer block B.

6. The block copolymer as claimed in claim 1, wherein, The polymer (A1) has a structure in which four or more polymer chains are bonded to a portion of the structure derived from the coupling agent, and the coupling agent has the functional group F.

7. The block copolymer as claimed in claim 1, wherein, The value β represented by the following formula (ii) in the polymer block A exceeds 0.20, β=(p+q) / (p+q+(0.5×r)+s) …(ii).

8. The block copolymer as claimed in claim 7, wherein, The value β is greater than 0.

60.

9. The block copolymer as claimed in claim 1, wherein, The polymer (A1) further comprises a polymer block C having structural units derived from conjugated diene compounds and structural units derived from aromatic vinyl compounds.

10. The block copolymer as claimed in claim 1, comprising a linear polymer (A2).

11. An adhesive obtained using a block copolymer as described in any one of claims 1 to 10.