Vinyl polymer and method for producing same

Abstract

This vinyl polymer comprises a polymer (P1) represented by formula (1), wherein the proportion of a polymer (P2) represented by formula (2) with respect to the total amount of the polymer (P1) and the polymer (P2) is not more than 20 mol%. In the formulae, A1 represents a polymer chain which has a structural unit derived from a vinyl monomer, and A2 is a single bond or represents a polymer chain which has a structural unit derived from a vinyl monomer. R1 is a residue resulting from removal of two iodine atoms of a bifunctional iodine polymerization control agent, and X1 is a hydrogen atom, or is a monovalent group which does not have iodine. R1 in formula (1) and R1 in formula (2) are the same group.　(1): I-A1-R1-A2-I (2): I-A1-R1-A2-X1

Description

Vinyl polymer and method for producing the same

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to Japanese Patent Application No. 2023-218675, filed on December 25, 2023, the entire contents of which are incorporated herein by reference. The present disclosure relates to vinyl polymers and methods for producing the same.

[0002] Vinyl polymers and block copolymers having crosslinkable functional groups are known as vinyl polymers for industrial use. In recent years, living radical polymerization, which is a polymerization method consisting of an initiation reaction and a propagation reaction without side reactions, has been widely used as a method for producing these vinyl polymers because it allows the synthesis of polymers with well-controlled molecular weight distribution and molecular structure.

[0003] Vinyl polymers having crosslinkable functional groups are widely used as curable resin compositions for producing cured products in various fields, such as paints, pressure-sensitive adhesives, adhesives, sealants, molded articles, rubber sheets, etc. For example, Patent Document 1 discloses that a vinyl polymer having crosslinkable silyl groups at both ends (a so-called telechelic polymer) is synthesized by atom transfer radical polymerization (ATRP) and the obtained vinyl polymer is used as a resin component of a curable resin composition. Furthermore, Patent Document 2 discloses that a vinyl polymer having crosslinkable functional groups at both ends (a telechelic polymer) is synthesized by iodine transfer polymerization and the obtained vinyl polymer is used as a resin component of a curable resin composition.

[0004] Block copolymers as vinyl polymers are widely used in various fields, for example, as thermoplastic elastomers, molding materials, etc. For example, Patent Document 3 discloses the production of a block copolymer having one or more methacrylic copolymer blocks (A) and one or more acrylic copolymer blocks (B) by reversible addition-fragmentation chain transfer polymerization (RAFT) method.

[0005] Japanese Patent Laid-Open No. 11-130931 Japanese Patent Laid-Open No. 2001-163918 Japanese Patent Laid-Open No. 2014-012782

[0006] Vinyl polymers having crosslinkable functional groups at both ends (telechelic polymers) have insufficient mechanical properties in the cured products obtained by curing the vinyl polymers, and the cured products have sometimes suffered from poor recovery after elongation. Furthermore, conventional block copolymers have sometimes produced molded products of the block copolymers with insufficient mechanical properties and recovery, and furthermore, the flowability during molding has been insufficient, making them less user-friendly.

[0007] The present disclosure has been made in view of the above circumstances, and has as its main object to provide a vinyl polymer from which a vinyl polymer having good fluidity can be obtained and from which a cured product or a molded product exhibiting good mechanical properties and recovery can be obtained.

[0008] The present inventors have conducted extensive research and found that, when a vinyl polymer is obtained by radically polymerizing a vinyl monomer in the presence of a bifunctional iodine-based polymerization regulator, the presence of a monofunctional iodine-based polymerization regulator in an amount greater than a predetermined amount in the polymerization system leads to a decrease in the mechanical properties and recovery of a cured product or molded article, and a decrease in the fluidity of the vinyl polymer. Based on this finding, specifically, the present disclosure provides the following vinyl polymer and a method for producing the same.

[0009] [1] A vinyl polymer comprising a polymer (P1) represented by the following formula (1), wherein the proportion of the polymer (P2) relative to the total amount of the polymer (P1) and a polymer (P2) represented by the following formula (2) is 20 mol % or less: １ -R １ -A ２ -I...(1) I-A １ -R １ -A ２ -X １ ... (2) (In formula (1) and formula (2), A １ represents a polymer chain having structural units derived from vinyl monomers, A ２ represents a single bond or a polymer chain having a structural unit derived from a vinyl monomer. １ is a residue obtained by removing two iodines from a bifunctional iodine-based polymerization inhibitor, and X １is a hydrogen atom or a monovalent group not containing iodine. １ and R in formula (2) １ are the same group.) [2] The vinyl polymer of [1], wherein the vinyl monomer contains a (meth)acrylic compound. [3] A method for producing a vinyl polymer by living radical polymerization, comprising a polymerization step of polymerizing a vinyl monomer in the presence of an iodine-based polymerization controller, wherein the iodine-based polymerization controller contains a compound (R1) that is a bifunctional iodine-based polymerization controller and optionally contains a compound (R2) represented by the following formula (4), and the proportion of the compound (R2) to the total amount of the compound (R1) and the compound (R2) is 20 mol % or less. １ -X １ ...(4) (In formula (4), R １ is a residue obtained by removing two iodines from the compound (R1), and X １ is a hydrogen atom or a monovalent group not containing iodine.) [4] The method for producing a vinyl polymer according to [3], wherein the polymerization step is a step of polymerizing the vinyl monomer to obtain an iodinated vinyl polymer having iodine at a terminal thereof, and further comprises a reaction step of reacting the iodinated vinyl polymer with a compound having a first functional group reactive with iodine and a second functional group different from the first functional group to obtain a polymer having the second functional group at a terminal thereof. [5] The method for producing a vinyl polymer according to [3], wherein the vinyl polymer is a BAB block copolymer having polymer block (A) and polymer block (B), and the polymerization step is a step of polymerizing vinyl monomers constituting polymer block (A) to obtain polymer block (A), and further comprises a step of polymerizing monomers constituting polymer block (B) in the presence of polymer block (A) obtained in the polymerization step to obtain the BAB block copolymer.

[0010] According to the present disclosure, a vinyl polymer having good fluidity can be obtained. Furthermore, by using the vinyl polymer of the present disclosure, a cured product or a molded article having good mechanical properties and recovery can be obtained.

[0011] The present disclosure will be described in detail below. In this specification, "(meth)acrylic" means acrylic and / or methacrylic, "(meth)acrylate" means acrylate and / or methacrylate, and "(meth)acrylo" means acrylo and / or methacrylo.

[0012] <<Vinyl Polymer>> The vinyl polymer of the present disclosure can be obtained by polymerizing a vinyl monomer (specifically, living radical polymerization) in the presence of a bifunctional iodine-based polymerization control agent. The bifunctional iodine-based polymerization control agent functions as a living radical polymerization control agent that precisely controls the molecular weight of the polymer in the vinyl monomer polymerization system. This allows the production of a polymer with a narrow molecular weight distribution.

[0013] One embodiment of the vinyl polymer of the present disclosure includes a polymer (P1) that is a vinyl polymer represented by the following formula (1), and optionally includes a polymer (P2) that is a vinyl polymer represented by the following formula (2). In the vinyl polymer (hereinafter also referred to as "vinyl polymer (P)") that includes the polymer (P1) and optionally includes the polymer (P2), the content of the polymer (P2) is 20 mol % or less with respect to the total amount (100 mol %) of the polymer (P1) and the polymer (P2). I-A １ -R １ -A ２ -I...(1) I-A １ -R １ -A ２ -X １ ... (2) (In formula (1) and formula (2), A １ represents a polymer chain having structural units derived from vinyl monomers, A ２ represents a single bond or a polymer chain having a structural unit derived from a vinyl monomer. １ is a residue obtained by removing two iodines from a bifunctional iodine-based polymerization inhibitor, and X １ is a hydrogen atom or a monovalent group not containing iodine. １ and R in formula (2) １ are the same group.)

[0014] In the above formula (1) and formula (2), R １ is a residue obtained by removing two iodines from a bifunctional iodine-based polymerization controller (hereinafter also referred to as "bifunctional controller (R1)"). The bifunctional controller (R1) is not particularly limited as long as it functions as a living radical polymerization controller that precisely controls the molecular weight and molecular weight distribution of the polymer. As this bifunctional controller (R1), a compound known as a bifunctional iodine-based polymerization controller can be appropriately used. The bifunctional controller (R1) is typically represented by the following formula (3): I-R １ -I...(3) (In formula (3), R １ is a residue obtained by removing two iodines from the bifunctional control agent (R1).

[0015] Examples of the bifunctional control agent (R1) include compounds having a carbon-iodine bond and two electron-withdrawing groups bonded to the carbon in the carbon-iodine bond per molecule. Examples of the electron-withdrawing group include aromatic groups, carbonyl groups, and cyano groups. Examples of the aromatic group include monovalent groups such as phenyl groups and methylphenyl groups, and divalent groups such as phenylene groups and methyl-substituted phenylene groups. The carbonyl group may be contained in -CO-O-, or may be adjacent to a hydrocarbon group on the side opposite to the carbon in the carbon-iodine bond. Specific examples of preferred bifunctional control agents (R1) include compounds represented by the following formula (3-1): (In formula (3-1), R ２ , R ３ , R ５ and R ６ are each independently a monovalent group, and R ４ is a divalent group. ２ , R ３ and R ４ is bonded to the carbon atom to which the iodine is bonded via an aromatic group, a carbonyl group, or a cyano group, and R ４ , R ５ and R ６ is bonded to the carbon atom to which the iodine is bonded via an aromatic group, a carbonyl group, or a cyano group.

[0016] Specific examples of the bifunctional control agent (R1) include compounds represented by the following formula:

[0017]

[0018]

[0019]

[0020]

[0021] X in the above formula (2) １ is a hydrogen atom or a monovalent group that does not contain iodine. １ is a monovalent group having no iodine, X １ is a group derived mainly from decomposition products generated during polymerization. When a vinyl monomer is polymerized in the presence of a bifunctional control agent (R1), one of the iodines at both ends of the bifunctional control agent (R1) may be removed due to thermal decomposition of the bifunctional control agent (R1). The polymer represented by the above formula (2) corresponds to a polymer obtained by polymerizing a vinyl monomer in the presence of an iodine-based polymerization control agent (hereinafter also referred to as a "monofunctional control agent (R2)") from which one of the two iodines contained in the bifunctional control agent (R1) has been removed by heat or the like. X １ Examples of R include a group derived from a decomposition product of an iodine-based polymerization controller and a group derived from a decomposition product of a radical polymerization initiator (for example, a peroxide). Specific examples include groups represented by the following formula (X-1), formula (X-2), formula (X-3), or formula (X-4). The groups represented by the following formulas (X-2) and (X-3) are examples of groups derived from a decomposition product of an iodine-based polymerization controller, and the R １ In addition, groups represented by the following formulae (X-1) and (X-4) are examples of groups derived from decomposition products (for example, peroxides) of radical polymerization initiators.

[0022] (In formula (X-1), formula (X-2), formula (X-3) or formula (X-4), R １０ , R １１ , R １２ , R １３ , R １４ , R １５ , R１６ , R １７ , R １８ , R １９ and R ２０ R each independently represents a hydrogen atom, an alkyl group, an aryl group, a heterocyclyl group, a cycloalkyl group, an alkoxycarbonyl group, a carboxy group, or a cyano group. ２１ represents a hydrogen atom, an alkyl group, or a group represented by the following formula (Y-1), formula (Y-2), or formula (Y-3): (In formula (Y-1), formula (Y-2) or formula (Y-3), R ２２ , R ２３ , R ２４ , R ２５ and R ２６ each independently represents a hydrogen atom, an alkyl group, an aryl group, a heterocyclyl group, a cycloalkyl group, an alkoxycarbonyl group, a carboxy group, or a cyano group.

[0023] The monofunctional control agent (R2) is typically represented by the following formula (4): I-R １ -X １ ...(4) (In formula (4), R １ is a residue obtained by removing two iodines from the bifunctional control agent (R1), and X １ is a hydrogen atom or a monovalent group that does not contain iodine.

[0024] In the above formula (4), R １ and X １ is R in the above formula (2). １ , X １ Specific examples of the monofunctional control agent (R2) include compounds exemplified as specific examples of the bifunctional control agent (R1), in which one of the two iodines is replaced with a hydrogen atom or X. １ Examples of compounds include those in which

[0025] A in the above formula (1) and formula (2) １ is a polymer chain having a structural unit derived from a vinyl monomer, and A ２ is a polymer chain having a structural unit derived from a single bond or a vinyl monomer. １ , A ２The polymer chain of the vinyl polymer (P) (i.e., the polymer chain of the polymer (P1) and the polymer (P2)) is constituted by these.

[0026] As the vinyl monomer constituting the polymer chain, various vinyl monomers having radical polymerizability can be used. Examples of the vinyl monomer include (meth)acrylic acid ester compounds, aromatic vinyl compounds, unsaturated carboxylic acids, unsaturated acid anhydrides, hydroxyl group-containing vinyl compounds, amino group-containing vinyl compounds, amide group-containing vinyl compounds, alkoxy group-containing vinyl compounds, nitrile group-containing vinyl compounds, and maleimide compounds. As the vinyl monomer, one of these may be used alone, or two or more may be used in combination.

[0027] Specific examples of vinyl monomers include the following compounds: (meth)acrylic acid ester compounds include (meth)acrylic acid alkyl ester compounds such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, amyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, ethylhexyl (meth)acrylate, n-dodecyl (meth)acrylate, and n-octadecyl (meth)acrylate; Aliphatic cyclic ester compounds of (meth)acrylic acid such as cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, tert-butylcyclohexyl (meth)acrylate, cyclododecyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentanyl (meth)acrylate; and aromatic ester compounds of (meth)acrylic acid such as phenyl methacrylate, benzyl (meth)acrylate, phenoxymethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, and 3-phenoxypropyl (meth)acrylate.

[0028] Examples of aromatic vinyl compounds include styrene, α-methylstyrene, β-methylstyrene, vinylxylene, o-methylstyrene, m-methylstyrene, p-methylstyrene, o-ethylstyrene, m-ethylstyrene, p-ethylstyrene, p-n-butylstyrene, p-isobutylstyrene, p-t-butylstyrene, o-methoxystyrene, m-methoxystyrene, p-methoxystyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, p-hydroxystyrene, m-hydroxystyrene, o-hydroxystyrene, p-isopropenylphenol, m-isopropenylphenol, o-isopropenylphenol, o-vinylbenzoic acid, m-vinylbenzoic acid, p-vinylbenzoic acid, and styrene-based compounds such as divinylbenzene, as well as vinylnaphthalene.

[0029] Examples of unsaturated carboxylic acids include (meth)acrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, cinnamic acid, monoalkyl esters of unsaturated dicarboxylic acids (monoalkyl esters of maleic acid, fumaric acid, itaconic acid, citraconic acid, etc.), etc. Examples of unsaturated acid anhydrides include maleic anhydride, itaconic anhydride, citraconic anhydride, etc.

[0030] Examples of hydroxy group-containing vinyl compounds include hydroxyalkyl (meth)acrylate compounds such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; polyalkylene glycol mono(meth)acrylate compounds such as polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, and polyethylene glycol-polypropylene glycol mono(meth)acrylate; unsaturated alcohols such as allyl alcohol; N-substituted maleimide compounds such as N-(4-hydroxyphenyl)maleimide; and hydroxy group-containing styrene compounds such as o-hydroxystyrene, m-hydroxystyrene, and p-hydroxystyrene.

[0031] Examples of the amino group-containing vinyl compound include dimethylaminomethyl (meth)acrylate, diethylaminomethyl (meth)acrylate, 2-dimethylaminoethyl (meth)acrylate, 2-diethylaminoethyl (meth)acrylate, 2-(di-n-propylamino)ethyl (meth)acrylate, 2-dimethylaminopropyl (meth)acrylate, 2-diethylaminopropyl (meth)acrylate, 2-(di-n-propylamino)propyl (meth)acrylate, 3-dimethylaminopropyl (meth)acrylate, 3-diethylaminopropyl (meth)acrylate, and 3-(di-n-propylamino)propyl (meth)acrylate.

[0032] Examples of the amide group-containing vinyl compound include (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, N-methylol(meth)acrylamide, etc. Examples of the alkoxy group-containing vinyl compound include 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-(n-propoxy)ethyl (meth)acrylate, 2-(n-butoxy)ethyl (meth)acrylate, 3-methoxypropyl (meth)acrylate, 3-ethoxypropyl (meth)acrylate, 2-(n-propoxy)propyl (meth)acrylate, 2-(n-butoxy)propyl (meth)acrylate, etc.

[0033] Examples of the nitrile group-containing vinyl compound include cyanomethyl (meth)acrylate, 1-cyanoethyl (meth)acrylate, 2-cyanoethyl (meth)acrylate, 1-cyanopropyl (meth)acrylate, 2-cyanopropyl (meth)acrylate, 3-cyanopropyl (meth)acrylate, 4-cyanobutyl (meth)acrylate, 6-cyanohexyl (meth)acrylate, 2-ethyl-6-cyanohexyl (meth)acrylate, 8-cyanooctyl (meth)acrylate, (meth)acrylonitrile, α-ethylacrylonitrile, α-isopropylacrylonitrile, α-chloroacrylonitrile, and α-fluoroacrylonitrile.

[0034] Examples of the maleimide compound include maleimide and N-substituted maleimide compounds. Examples of the N-substituted maleimide compound include N-alkyl-substituted maleimide compounds such as N-methylmaleimide, N-ethylmaleimide, N-n-propylmaleimide, N-isopropylmaleimide, N-n-butylmaleimide, N-isobutylmaleimide, N-tert-butylmaleimide, N-pentylmaleimide, N-hexylmaleimide, N-heptylmaleimide, N-octylmaleimide, N-laurylmaleimide, and N-stearylmaleimide; N-cyclopentylmaleimide and N N-cycloalkyl-substituted maleimide compounds such as N-cyclohexylmaleimide; N-aralkyl-substituted maleimide compounds such as N-benzylmaleimide; and N-aryl-substituted maleimide compounds such as N-phenylmaleimide, N-(4-hydroxyphenyl)maleimide, N-(4-acetylphenyl)maleimide, N-(4-methoxyphenyl)maleimide, N-(4-ethoxyphenyl)maleimide, N-(4-chlorophenyl)maleimide, and N-(4-bromophenyl)maleimide. In addition to the above compounds, dialkyl esters of unsaturated dicarboxylic acids, vinyl ester compounds, vinyl ether compounds, and the like can also be used in the production of the vinyl polymer (P).

[0035] The monomer constituting the polymer chain of the vinyl polymer (P) preferably contains a (meth)acrylic compound, and particularly preferably contains a compound represented by the following formula (5): CH ２ =CR ７ -C(=O)-O-(R ８ O) ｎ -R ９ ...(5) (In formula (5), R ７ represents a hydrogen atom or a methyl group, and R ８ represents a linear or branched alkylene group having 2 to 6 carbon atoms, and R ９represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. n represents an integer of 0 to 100.

[0036] Specific examples of the compound represented by the formula (5) include the (meth)acrylic acid ester compounds, alkoxy group-containing vinyl compounds, (meth)acrylic acid hydroxyalkyl compounds, and polyalkylene glycol mono(meth)acrylate compounds exemplified above. Among these, it is more preferable to include a (meth)acrylic acid ester compound, since it is possible to obtain a vinyl polymer (P) having good properties such as heat resistance. The compound represented by the formula (5) is a compound represented by the formula (5) containing the group "-(R ８ O)n-R ９ " preferably has 2 or more carbon atoms, and more preferably has 3 or more carbon atoms. ８ O)n-R ９ The upper limit of the number of carbon atoms in " is preferably 10 or less, more preferably 8 or less, from the viewpoint of maintaining polymerization controllability.

[0037] Among the monomers constituting the polymer chain of the vinyl polymer (P), the amount of the (meth)acrylic compound is preferably 50 mol % or more, more preferably 70 mol % or more, and even more preferably 80 mol % or more, based on the total amount of the monomers constituting the polymer chain.

[0038] The vinyl polymer (P) may contain a polymer (P1) as a main component and a polymer (P2) as an optional component. When a vinyl monomer is polymerized in the presence of a bifunctional control agent (R1), one of the iodines at both ends of the bifunctional control agent (R1) may be removed (i.e., the iodine terminals of the iodine-based polymerization control agent may be reduced) due to thermal decomposition of the bifunctional control agent (R1). Furthermore, if one of the iodines at both ends of the bifunctional control agent (R1) is removed, polymerization may be initiated only from the remaining iodine terminal, reducing the precision controllability of the molecular weight, which may result in the vinyl polymer containing a large amount of high molecular weight compounds. In this case, there is a concern that the fluidity of the vinyl polymer (P) or a polymer (e.g., a modified product) obtained using the vinyl polymer (P) as a raw material may be reduced. Furthermore, when attempting to introduce a desired functional group into the terminal of a polymer using terminal iodine, there is a concern that the reduction in terminal iodine may prevent sufficient functionalization of the polymer terminal. If the polymer terminals cannot be sufficiently functionalized, the fluidity of the vinyl polymer (P) may decrease, or uniform crosslinking may not be formed in the cured product or molded article, resulting in deterioration of the mechanical properties of the cured product or molded article.

[0039] In this regard, the vinyl polymer (P) has a low content of polymer (P2), specifically, the content of polymer (P2) in the vinyl polymer (P) is 20 mol% or less relative to the total amount of polymer (P1) and polymer (P2). If the content of polymer (P2) in the vinyl polymer (P) exceeds 20 mol% relative to the total amount of polymer (P1) and polymer (P2), the flowability of the vinyl polymer (P) or its modified product tends to be insufficient. Furthermore, if the content of polymer (P2) exceeds 20 mol% relative to the total amount of polymer (P1) and polymer (P2), the mechanical properties and recovery of the cured product or molded product obtained from the vinyl polymer (P) will be poor.

[0040] In order to improve the fluidity of the vinyl polymer (P) or its modified product, and to improve the mechanical properties and recovery of the cured product or molded product obtained from the vinyl polymer (P) or its modified product, the content of the polymer (P2) in the vinyl polymer (P) is preferably 15 mol% or less, more preferably 12 mol% or less, even more preferably 10 mol% or less, even more preferably 7 mol% or less, and even more preferably 5 mol% or less, relative to the total amount of the polymer (P1) and the polymer (P2). The lower limit of the content of the polymer (P2) is not particularly limited, and it may be 0 mol% or more. From the viewpoint of ease of production of the vinyl polymer (P) or its modified product, the content of the polymer (P2) in the vinyl polymer (P) is, for example, 0.01 mol% or more, or may be 0.05 mol% or more, or may be 0.1 mol% or more, relative to the total amount of the polymer (P1) and the polymer (P2).

[0041] In this specification, the polymer (P2) contained in the vinyl polymer (P) can be identified by the following method. First, the vinyl polymer (P) is subjected to gel permeation chromatography (GPC) separation under the conditions described in the Examples below to obtain fractions. Next, the obtained fractions (concentrates) are separated. １ H-NMR measurement was performed to determine whether R in the above formula (1) and formula (2) １ The polymer (P2) is identified by the ratio of the integral value of the proton peak derived from the terminal iodine to the integral value of the proton peak derived from the terminal iodine. １ The integral value of the proton peak derived from the vinyl polymer (P) is observed to be 0.5 times that of the polymer (P1). Utilizing this, it can be confirmed that the structure of the compound in the fraction obtained by GPC fractionation is the structure of the polymer (P2). The details of the method for measuring the content of the polymer (P2) contained in the vinyl polymer (P) follow the method described in the Examples below.

[0042] The content of the polymer (P2) in the vinyl polymer (P) can be adjusted, for example, by controlling the temperature during polymerization or adjusting the monomer concentration during polymerization. For example, the content of the polymer (P2) in the vinyl polymer (P) can be reduced by lowering the temperature during polymerization or increasing the monomer concentration during polymerization.

[0043] The vinyl polymer (P) may be a homopolymer obtained by polymerizing one type of monomer, or a copolymer obtained by polymerizing two or more types of monomers. The type of copolymer is not particularly limited, and examples thereof include random copolymers, block copolymers, alternating copolymers, and graft copolymers.

[0044] <Production of Vinyl Polymer (P)> The vinyl polymer (P) can be obtained by a living radical polymerization method including a step of polymerizing a vinyl monomer in the presence of an iodine-based polymerization control agent (hereinafter also referred to as the "polymerization step"). That is, in the present disclosure, a vinyl polymer can be obtained by iodine transfer polymerization (ITP) using an iodine-based polymerization control agent. In iodine transfer polymerization, an iodine compound (i.e., an iodine-based polymerization control agent) acts as an exchange chain transfer agent for radicals generated by a free radical polymerization initiator, and polymerization proceeds.

[0045] For example, in the case of a solution polymerization method, a solvent, a monomer, and an iodine-based polymerization inhibitor are charged into a reactor, a radical polymerization initiator is added, and the mixture is heated as necessary to polymerize, thereby obtaining the target vinyl polymer (P). The method for charging each raw material may be a batch-type initial lump-sum charge in which all raw materials are charged at once, a semi-continuous charge in which at least a portion of the raw materials are continuously fed into the reactor, or a continuous polymerization method in which all raw materials are continuously fed and the product is continuously withdrawn from the reactor at the same time. Continuous polymerization methods may be tubular, column, continuous stirred tank (CSTR), or a combination thereof. Of these, the tubular and column types are preferred because they can narrow the molecular weight distribution of the resulting vinyl polymer.

[0046] (Iodine-based polymerization controller) The iodine-based polymerization controller used in the polymerization of the vinyl polymer (P) contains a bifunctional iodine-based polymerization controller (i.e., a bifunctional controller (R1)) and optionally contains a monofunctional controller (R2) represented by the above formula (3). In the iodine-based polymerization controller used in the production of the vinyl polymer (P), the content of the monofunctional controller (R2) is 20 mol% or less relative to the total amount (100 mol%) of the bifunctional controller (R1) and the monofunctional controller (R2). If the content of the monofunctional controller (R2) exceeds 20 mol% relative to the total amount of the bifunctional controller (R1) and the monofunctional controller (R2), the flowability of the vinyl polymer (P) or its modified product obtained by polymerization of the vinyl monomer is insufficient. In addition, the mechanical properties and recovery of the cured product or molded product produced using the vinyl polymer (P) or its modified product are insufficient.

[0047] From the viewpoint of improving the flowability of the vinyl polymer (P) or its modified product and improving the mechanical properties and recovery of the cured product or molded product obtained from the vinyl polymer (P) or its modified product, the content of the monofunctional control agent (R2) in the iodine-based polymerization control agent used in the production of the vinyl polymer (P) is preferably 15 mol% or less, more preferably 12 mol% or less, even more preferably 10 mol% or less, even more preferably 7 mol% or less, and even more preferably 5 mol% or less, relative to the total amount of the bifunctional control agent (R1) and the monofunctional control agent (R2). The lower limit of the content of the monofunctional control agent (R2) is not particularly limited, but from the viewpoint of easy availability of the iodine-based polymerization control agent, it is, for example, 0.01 mol% or more, or may be 0.05 mol% or more, or may be 0.1 mol% or more, relative to the total amount of the bifunctional control agent (R1) and the monofunctional control agent (R2).

[0048] The content of the monofunctional control agent (R2) in the iodine-based polymerization control agent used in the production of the vinyl polymer (P) can be adjusted, for example, by subjecting a mixture of the bifunctional control agent (R1) and the monofunctional control agent (R2) to a purification treatment. The purification method is not particularly limited, and examples thereof include recrystallization, reprecipitation, extraction, sublimation, chromatography, column adsorption, and the like. In this case, the content of the monofunctional control agent (R2) in the iodine-based polymerization control agent can be adjusted by appropriately selecting the number of purification rounds and the purification method. The mixture of the bifunctional control agent (R1) and the monofunctional control agent (R2) may be purified multiple times. When purification is performed multiple times, the purification method for each round may be the same or different.

[0049] The identification and content of the monofunctional inhibitor (R2) contained in the iodine-based polymerization inhibitor was calculated as follows: １ This can be done by H-NMR measurement. １ According to H-NMR measurement, R in the above formula (3) and formula (4) １ Since a proton peak derived from the iodine-containing polymerization inhibitor and a proton peak derived from the terminal iodine can be observed, the structures of the iodine-containing polymerization inhibitor and the monofunctional polymerization inhibitor (R2) can be determined by using these proton peaks.

[0050] The content of the monofunctional inhibitor (R2) in the iodine-based polymerization inhibitor is R １ The integral value of the proton peak (a) derived from the terminal iodine can be calculated from the integral value of the proton peak (b) derived from the terminal iodine when the integral value of the proton peak (a) derived from the terminal iodine is normalized to 1. Specifically, when the iodine-based polymerization controller contains a monofunctional controller (R2), the R １ The integral value of the proton peak (b) derived from the terminal iodine relative to the integral value of the proton peak (a) derived from is observed to be 0.5 times that in the case of the bifunctional control agent (R1). １When the integral value of the proton peak (a) derived from the terminal iodine is normalized to 1, the integral value of the proton peak (b) derived from the terminal iodine is Ib, the molar ratio of the bifunctional control agent (R1) in the iodine-based polymerization control agent is α, and the molar ratio of the monofunctional control agent (R2) is β, the relationship expressed by the following two mathematical formulas is established. Note that It in the mathematical formula is the ratio of R １ is the integral of the proton peak (b) derived from terminal iodine relative to the integral of the proton peak (a) derived from terminal iodine. α + β = 1 (integral value of (a) normalized to 1) α + 0.5β = Ib / It Therefore, by solving these simultaneous equations to determine α and β, the content of the monofunctional polymerization controller (R2) in the iodine-based polymerization controller can be calculated.

[0051] The radical polymerization initiator used in the polymerization can be a known radical polymerization initiator such as an azo compound, an organic peroxide, or a persulfate. Among these, azo compounds are preferred because they are easy to handle safely and are less likely to cause side reactions during radical polymerization. Specific examples of azo compounds include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), dimethyl-2,2'-azobis(2-methylpropionate), 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis[N-(2-propenyl)-2-methylpropionamide], and 2,2'-azobis(N-butyl-2-methylpropionamide). A single radical polymerization initiator may be used, or two or more may be used in combination.

[0052] The amount of radical polymerization initiator used is not particularly limited, but from the viewpoint of obtaining a polymer with a narrower molecular weight distribution, it is preferably 0.5 mol or less, and more preferably 0.2 mol or less, per mol of iodine-based polymerization control agent. Furthermore, from the viewpoint of stably carrying out the polymerization reaction, the lower limit of the amount of radical polymerization initiator used is preferably 0.01 mol or more, and more preferably 0.05 mol or more, per mol of iodine-based polymerization control agent. The amount of radical polymerization initiator used per mol of iodine-based polymerization control agent is preferably 0.01 to 0.5 mol, and more preferably 0.05 to 0.2 mol.

[0053] The polymerization reaction is preferably carried out in a polymerization solvent known in living radical polymerization. The polymerization solvent used is preferably an organic solvent capable of dissolving the monomer, and examples thereof include aromatic compounds such as benzene, toluene, xylene, and anisole; ester compounds such as methyl acetate, propyl acetate, and butyl acetate; ketone compounds such as acetone, methyl ethyl ketone, and cyclohexanone; and nitrile compounds such as acetonitrile. One polymerization solvent may be used alone, or two or more may be used in combination. When a hydrophilic monomer is used, alcohol, water, or the like can be used as the polymerization solvent. The amount of polymerization solvent used is preferably 5 to 200 parts by mass, more preferably 10 to 100 parts by mass, per 100 parts by mass of the total amount of monomers used in the reaction. Using an amount of polymerization solvent of 100 parts by mass or less is preferred because a high polymerization rate can be achieved in a short period of time.

[0054] In the polymerization reaction by living radical polymerization, the reaction temperature is preferably 40°C or higher and 100°C or lower, more preferably 45°C or higher and 90°C or lower, and even more preferably 50°C or higher and 80°C or lower. A reaction temperature of 40°C or higher is preferred because it allows the polymerization reaction to proceed smoothly, while a reaction temperature of 100°C or lower is preferred because it can suppress thermal decomposition and side reactions of the iodine-based polymerization control agent and also alleviates restrictions on the polymerization initiator and solvent that can be used. The reaction time can be appropriately set depending on the monomers used, etc., but is preferably 1 hour or higher and 48 hours or lower, and more preferably 2 hours or higher and 24 hours or lower.

[0055] In the production method of the present disclosure, polymerization is carried out using an iodine-based polymerization control agent containing a bifunctional control agent (R1), so a BAB block copolymer having polymer block (A) and polymer block (B) can be efficiently obtained with as few steps as possible. Specifically, by adopting a method that further includes the following second polymerization step in addition to the above polymerization step (hereinafter referred to as the "first polymerization step"), a BAB block copolymer consisting of polymer block (B) / polymer block (A) / polymer block (B) can be efficiently obtained as the vinyl polymer (P). First polymerization step: A step of obtaining polymer block (A) by polymerizing vinyl monomers that constitute polymer block (A). Second polymerization step: A step of obtaining a BAB block copolymer by polymerizing monomers that constitute polymer block (B) in the presence of polymer block (A) obtained in the first polymerization step.

[0056] In the above production method, first, in the first polymerization step, monomers constituting the polymer block (A) located at the center of the target BAB block copolymer are polymerized to obtain the polymer block (A). This first polymerization step produces a terminally iodized polymer block (A) that contains a vinyl polymer having iodine at both ends as a main component and a vinyl polymer having iodine at one end as an optional component.

[0057] Subsequently, in the second polymerization step, the monomers constituting the polymer block (B) are polymerized in the presence of the terminally iodinated polymer block (A) to form the polymer block (B). This allows for a triblock copolymer consisting of polymer block (B) / polymer block (A) / polymer block (B). Furthermore, by subsequently carrying out the third polymerization step, the fourth polymerization step, etc., a multiblock copolymer having five or more blocks can also be obtained. The polymerization method using a bifunctional control agent (R1) simplifies the vinyl polymer production process compared to the production method in which each block is polymerized sequentially. Furthermore, a vinyl polymer having iodine at both ends (telechelic polymer) can be obtained.

[0058] A preferred embodiment of the BAB block copolymer is a triblock copolymer having a polymer block (B) that constitutes a hard segment and can serve as a pseudo-crosslinking point, and a polymer block (A) that can serve as a soft segment. From the viewpoint of inducing physical crosslinks between the hard segments and thereby obtaining a molded article exhibiting good mechanical properties, the polymer block (B) preferably has a higher glass transition temperature (Tg) than the polymer block (A), for example, a Tg of greater than 20°C. Furthermore, in terms of imparting flexibility to the vinyl copolymer (P), the polymer block (B) is preferably a (meth)acrylic polymer block primarily composed of a (meth)acrylic compound. A block copolymer having such a configuration can obtain a molded article exhibiting good flowability and excellent mechanical properties and recovery. To uniformly form physical crosslinks between the hard segments and thereby obtain a molded article exhibiting good mechanical properties, it is important that the polymer has hard segments at both ends. According to the production method of the present disclosure, a vinyl polymer with a low content of polymers having a hard segment at only one end of the polymer can be obtained, thereby obtaining a molded article exhibiting excellent mechanical properties.

[0059] From the viewpoint of coloration, etc., it may be preferable to remove iodine from the terminals of the BAB block copolymer obtained by the above polymerization. Therefore, the BAB block copolymer obtained by the above polymerization may be subjected to a treatment for removing the terminal iodine. When removing the terminal iodine from the BAB block copolymer, the iodine can be removed from the terminals of the BAB block copolymer by reacting the BAB block copolymer with a compound having a functional group capable of reacting with terminal iodine (e.g., a carboxylic acid, an amine, etc.).

[0060] According to the above polymerization, a vinyl polymer (P) can be obtained that contains a polymer (P1) represented by the above formula (1) and optionally contains a polymer (P2) represented by the above formula (2). That is, the vinyl polymer (P) mainly contains a polymer (P1) having iodine at both ends of the polymer, and optionally contains a polymer (P2) having iodine at one end of the polymer. By introducing a desired functional group into the vinyl polymer (P) using the terminal iodine, a telechelic polymer having the desired functional group at both ends of the polymer can be obtained. In particular, the vinyl polymer (P) contains a small amount of the polymer (P2) having iodine at one end of the polymer, while containing a sufficient amount of the polymer (P1) having iodine at both ends of the polymer. By producing a telechelic polymer using such a vinyl polymer (P), a polymer assembly exhibiting desired physical properties can be obtained.

[0061] Another aspect of the vinyl polymer of the present disclosure is a modified product (telechelic polymer) in which a functional group is introduced by utilizing the terminal iodine possessed by the vinyl polymer (P). Examples of methods for obtaining such modified products include methods comprising the following polymerization and reaction steps: Polymerization step: A step of obtaining an iodinated vinyl polymer having iodine at the terminal by polymerizing a vinyl monomer; Reaction step: A step of obtaining a polymer having a second functional group at the terminal (i.e., a modified product) by reacting the iodinated vinyl polymer obtained by the polymerization step with a compound having a first functional group reactive with iodine and a second functional group different from the first functional group.

[0062] The polymerization step corresponds to the polymerization step described above. In the polymerization step, a homopolymer may be obtained as an iodinated vinyl polymer by performing living radical polymerization using one type of monomer. Alternatively, a copolymer may be obtained by performing living radical polymerization using two or more types of monomers. The type of copolymer is not particularly limited, and examples thereof include random copolymers, block copolymers, alternating copolymers, and graft copolymers.

[0063] In the reaction step, the terminal iodine of the iodinated vinyl polymer is reacted with a compound having a first functional group and a second functional group (hereinafter also referred to as a "reactive compound"). Examples of the first functional group include an amino group, a hydroxyl group, a thiol group, a cyano group, and an alkoxy group. Examples of the second functional group include a crosslinkable functional group, such as a crosslinkable silyl group, a silanol group, a carboxyl group, a hydroxyl group, an epoxy group, an oxazoline group, an isocyanate group, a (meth)acryloyl group, and a vinyl group. Among these, the crosslinkable functional group is preferably a crosslinkable silyl group, and more preferably an alkoxysilyl group, in terms of the excellent mechanical properties of the cured product obtained using the vinyl polymer as a modified product and the ease of controlling the reactivity.

[0064] The reaction between the iodinated vinyl polymer and the reactive compound can be carried out in a solvent, if necessary. Examples of the solvent include the same solvents as those exemplified as solvents that can be used in the polymerization reaction. The reaction temperature is, for example, 40°C or higher and 100°C or lower, and the reaction time is, for example, 1 to 24 hours.

[0065] By such a reaction, the target living radical polymer can be obtained. When the polymer obtained by the reaction is subjected to isolation and / or purification treatment, known methods can be appropriately adopted for these treatments.

[0066] The vinyl polymer of the present disclosure preferably has a polystyrene-equivalent number average molecular weight (Mn) measured by gel permeation chromatography (GPC) in the range of 2,000 to 1,000,000. An Mn of 2,000 or more facilitates the development of desired properties in the vinyl polymer (P). Furthermore, an Mn of 1,000,000 or less is preferred in that processability, such as coatability, and ease of handling can be sufficiently ensured. The Mn of the vinyl polymer is more preferably 5,000 or more, even more preferably 8,000 or more, and particularly preferably 10,000 or more. The upper limit of the Mn of the vinyl polymer is more preferably 800,000 or less, even more preferably 700,000 or less, even more preferably 600,000 or less, and even more preferably 500,000 or less. The preferred range of the Mn of the vinyl polymer can be determined by appropriately combining the above-mentioned upper and lower limits. The Mn of the vinyl polymer (P) is more preferably 5,000 to 800,000, even more preferably 8,000 to 700,000, and still more preferably 10,000 to 600,000.

[0067] The weight average molecular weight (Mw) of the vinyl polymer measured by GPC in terms of polystyrene is preferably in the range of 2,000 to 1,000,000. The Mw of the vinyl polymer is more preferably 5,000 or more, even more preferably 8,000 or more, and even more preferably 10,000 or more. The upper limit of the Mw of the vinyl polymer is more preferably 800,000 or less, even more preferably 700,000 or less, even more preferably 600,000 or less, and even more preferably 500,000 or less. The Mw range of the vinyl polymer (P) is more preferably 5,000 to 800,000, even more preferably 8,000 to 700,000, and even more preferably 10,000 to 600,000.

[0068] The molecular weight distribution (Mw / Mn) of the vinyl polymer is preferably 3.0 or less, since this makes it easier for the vinyl polymer to exhibit desired properties. The molecular weight distribution (Mw / Mn) is more preferably 2.5 or less, and even more preferably 2.0 or less. The lower limit of the molecular weight distribution (Mw / Mn) is not particularly limited, but from the viewpoint of ease of production, it is, for example, 1.01 or more.

[0069] The vinyl polymers obtained by the present disclosure can be used in a wide range of applications. Specifically, they can be used in a variety of applications, such as sealants, adhesives, pressure-sensitive adhesives, paints, dispersants, industrial rubber, binders, and coating agents. Examples of application fields include civil engineering and construction materials, automobile parts, home appliance and office automation equipment parts, medical equipment parts, packaging materials, daily necessities, electric wires, and miscellaneous goods.

[0070] <<Curable Resin Composition and Cured Product>> The above-mentioned modified product in which a functional group is introduced by utilizing the terminal iodine of the vinyl polymer (P) can be used as one component of a curable resin composition. A curable resin composition containing such a modified product is useful as a curable resin composition for producing a cured product in the various fields mentioned above. In addition, a curable resin composition containing the above-mentioned modified product can provide a cured product having excellent mechanical properties and recovery properties.

[0071] The curable resin composition of the present disclosure may contain other components in addition to the modified product described above, as necessary. Known components blended into curable resin compositions for various applications can be used as appropriate as other components. Specific examples of other components include thermal or photopolymerization initiators, crosslinking agents, curing accelerators, other polymers, plasticizers, fillers, pigments, adhesion promoters, dehydrating agents, antioxidants, UV absorbers, oils, solvents, etc. The blending amounts of these components can be appropriately set depending on the respective components.

[0072] The present disclosure will be specifically described below based on examples. However, the present disclosure is not limited to these examples. In the following, "parts" and "%" mean "parts by mass" and "% by mass", respectively, unless otherwise specified.

[0073] The methods for measuring the molecular weight of the vinyl polymer obtained by living radical polymerization in each example and the proportion of the polymer contained in the vinyl polymer are described below.

[0074] <Molecular Weight Measurement> The obtained vinyl polymer was subjected to gel permeation chromatography (GPC) measurement under the conditions described below to obtain the number average molecular weight (Mn) and weight average molecular weight (Mw) in terms of polystyrene. The molecular weight distribution (Mw / Mn) was calculated from the obtained values. Measurement conditions Column: TSKgel SuperMultiporeHZ-M (manufactured by Tosoh) x 4 Solvent: Tetrahydrofuran Temperature: 40°C Detector: RI Flow rate: 600 μL / min

[0075] <Proportion of polymer (P1) and polymer (P2) contained in vinyl polymer> The proportion of polymer (P1) and polymer (P2) contained in the vinyl polymer can be determined by the following method. １ When the proton peak derived from the terminal iodine is designated as peak (a) and the proton peak derived from the terminal iodine is designated as peak (b), １ The integral value of the theoretical peak (a) derived from the structural formula of the polymer (P1) in the H-NMR measurement is normalized to 1, and the integral value of the peak (b) is expressed as I １ The integral value of peak (b) when the integral value of the actually measured peak (a) is normalized to 1 is defined as I ２ When the integral value of peak (a) of polymer (P2) is normalized to 1, the integral value of peak (b) is observed to be 0.5 times that of polymer (P1). Therefore, when the molar ratio of polymer (P1) is α and the molar ratio of polymer (P2) is β, α + β = 1 and α + 0.5β = I ２ / I １ The simultaneous equations were solved to determine α and β, thereby calculating the proportions of polymer (P1) and polymer (P2) in the vinyl polymer obtained by polymerization.

[0076] 1. Synthesis of Iodine-Based Polymerization Control Agent [Synthesis Example 1 (Synthesis of 1,4-bis(iodomethyl)benzene (Bz-II))] Under a nitrogen atmosphere, p-xylene-α,α'-diol (62.5 mmol, 8.64 g) and NaI (250 mmol, 37.5 g) were added and dissolved in dehydrated acetonitrile (500 mL). ３ An ether complex (250 mmol, 30.8 mL) was slowly added dropwise. After the addition was complete, the mixture was allowed to react at room temperature for 30 minutes. The reaction mixture was poured into ice water (250 g) and stirred. 20% sodium thiosulfate (250 mL) was added and the mixture was transferred to a separatory funnel. Extraction was performed with toluene (3 x 500 mL), and the organic layer was washed with distilled water (2 x 200 mL) and saturated brine (200 mL) in that order. The mixture was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated using a rotary evaporator. The resulting crude product was purified by column chromatography.

[0077] Synthesis Example 2 (Synthesis of 4-methyliodomethylbenzene (Bz-I)) Under a nitrogen atmosphere, 4-methylbenzyl alcohol (125 mmol, 15.3 g) and NaI (250 mmol, 37.5 g) were added and dissolved in dehydrated acetonitrile (500 mL). ３ An ether complex (250 mmol, 30.8 mL) was slowly added dropwise. After the addition was complete, the mixture was allowed to react at room temperature for 30 minutes. The reaction mixture was poured into ice water (250 g) and stirred. 20% sodium thiosulfate (250 mL) was added and the mixture was transferred to a separatory funnel. Extraction was performed with toluene (3 x 500 mL), and the organic layer was washed with distilled water (2 x 200 mL) and saturated brine (200 mL) in that order. The mixture was dried over anhydrous sodium sulfate and filtered, and the filtrate was concentrated using a rotary evaporator. The resulting crude product was purified by column chromatography.

[0078] 2. Polymer Production [Example 1 (Production of Polymer 1)] Bz-II (4.47 g), 2,2'-azobis(2-methylbutyronitrile) (hereinafter also referred to as "ABN-E") (0.24 g), n-butyl acrylate (hereinafter also referred to as "BA") (500 g), and anisole (47.3 g) were charged into a 1 L flask equipped with a stirrer and a thermometer, and the mixture was thoroughly degassed by nitrogen bubbling, and polymerization was initiated in a thermostatic bath at 70°C. After 4 hours, the mixture was cooled to room temperature to terminate the reaction. The polymerization solution was purified by reprecipitation from methanol and vacuum dried to obtain Polymer 1. The molecular weight properties of the obtained Polymer 1 were determined by GPC measurement (polystyrene equivalent) to be Mn 41,000, Mw 62,000, and Mw / Mn 1.51. In addition, １ From H-NMR, the proportion of polymer (P1) in polymer 1 was calculated to be 100 mol %, and the proportion of polymer (P2) was calculated to be 0 mol %.

[0079] Example 2 (Production of Polymer 2) Polymer 2 was obtained by the same procedure as in Example 1, except that the amount of Bz-II was changed to 4.25 g and 0.14 g of Bz-I was added. The molecular weight properties of Polymer 2 were determined by GPC measurement to be Mn 42,000, Mw 64,000, and Mw / Mn 1.52. １ From H-NMR, the proportion of polymer (P1) in polymer 2 was calculated to be 95 mol %, and the proportion of polymer (P2) was calculated to be 5 mol %.

[0080] Example 3 (Production of Polymer 3) Polymer 3 was obtained by the same procedure as in Example 2, except that the amount of Bz-II was changed to 4.02 g and the amount of Bz-I was changed to 0.29 g. The molecular weight properties of Polymer 3 were determined by GPC measurement to be Mn 42,000, Mw 64,000, and Mw / Mn 1.52. １ From H-NMR, the proportion of polymer (P1) in polymer 3 was calculated to be 90 mol %, and the proportion of polymer (P2) was calculated to be 10 mol %.

[0081] Example 4 (Production of Polymer 4) Polymer 4 was obtained by the same procedure as in Example 2, except that the amount of Bz-II was changed to 3.80 g and the amount of Bz-I was changed to 1.66 g. The molecular weight properties of Polymer 4 were determined by GPC measurement to be Mn 42,000, Mw 65,000, and Mw / Mn 1.55. １ From H-NMR, the proportion of polymer (P1) in polymer 4 was calculated to be 86 mol %, and the proportion of polymer (P2) was calculated to be 14 mol %.

[0082] Example 5 (Production of Polymer 5) Polymer 5 was obtained by the same procedure as in Example 2, except that the amount of Bz-II was changed to 3.58 g and the amount of Bz-I was changed to 0.58 g. The molecular weight properties of Polymer 5 were determined by GPC measurement to be Mn 43,000, Mw 69,000, and Mw / Mn 1.60. １ From H-NMR, the proportion of polymer (P1) in polymer 5 was calculated to be 80 mol %, and the proportion of polymer (P2) was calculated to be 20 mol %.

[0083] Comparative Example 1 (Production of Polymer 6) Polymer 6 was obtained by the same procedure as in Example 2, except that the amount of Bz-II was changed to 3.35 g and the amount of Bz-I was changed to 0.72 g. The molecular weight properties of Polymer 6 were determined by GPC measurement to be Mn 43,000, Mw 71,000, and Mw / Mn 1.65. １ From H-NMR, the proportion of polymer (P1) was calculated to be 75 mol %, and the proportion of polymer (P2) was calculated to be 25 mol %.

[0084]

[0085] Example 6 (Production of Modified Product 1) Polymer 1 (100 g) and anisole (100 g) were placed in a 500 mL flask equipped with a stirrer and a thermometer and dissolved. After dissolution, 3-aminopropyltrimethoxysilane (hereinafter also referred to as "ATMS") (18 g) was added, and the mixture was heated in a constant temperature bath at 70°C for 5 hours. The resulting modified product solution was purified by reprecipitation from methanol and vacuum dried to obtain Modified Product 1. The molecular weight properties of Modified Product 1 were determined by GPC measurement to be Mn 41,000, Mw 63,000, and Mw / Mn 1.53.

[0086] Example 7 (Production of Modified Product 2) The same procedure as in Example 6 was carried out, except that Polymer 1 was changed to Polymer 2 (102 g), to obtain Modified Product 2. The molecular weight properties of Modified Product 2 were determined by GPC measurement to be Mn 42,000, Mw 65,000, and Mw / Mn 1.55.

[0087] Example 8 (Production of Modified Product 3) The same procedure as in Example 6 was carried out, except that Polymer 1 was changed to Polymer 3 (102 g), to obtain Modified Product 3. The molecular weight properties of Modified Product 3 were determined by GPC measurement to be Mn 42,000, Mw 66,000, and Mw / Mn 1.57.

[0088] Example 9 (Production of Modified Product 4) The same procedure as in Example 6 was carried out, except that Polymer 1 was changed to Polymer 4 (102 g), to obtain Modified Product 4. The molecular weight properties of Modified Product 4 were determined by GPC measurement to be Mn 43,000, Mw 68,000, and Mw / Mn 1.58.

[0089] Example 10 (Production of Modified Product 5) The same procedure as in Example 6 was carried out, except that Polymer 1 was changed to Polymer 5 (105 g), to obtain Modified Product 5. The molecular weight properties of Modified Product 5 were determined by GPC measurement to be Mn 43,000, Mw 69,000, and Mw / Mn 1.60.

[0090] Comparative Example 2 (Production of Modified Product 6) The same procedure as in Example 6 was carried out, except that Polymer 1 was changed to Polymer 6 (105 g), to obtain Modified Product 6. The molecular weight properties of Modified Product 6 were determined by GPC measurement to be Mn 43,000, Mw 71,000, and Mw / Mn 1.65.

[0091]

[0092] Example 11 (Production of Polymer 7) Polymer 7 was obtained by the same procedure as in Example 1, except that the amount of Bz-II was changed to 2.55 g and the amount of ABN-E was changed to 0.41 g. The molecular weight properties of Polymer 7 were determined by GPC measurement to be Mn 71,000, Mw 110,000, and Mw / Mn 1.55. １ From H-NMR, the proportion of polymer (P1) in polymer 7 was calculated to be 100 mol %, and the proportion of polymer (P2) was calculated to be 0 mol %.

[0093] Example 12 (Production of Polymer 8) The same procedure as in Example 11 was carried out, except that the amount of Bz-II was changed to 2.42 g and 0.08 g of Bz-I was added, to obtain Polymer 8. The molecular weight properties of Polymer 8 were determined by GPC measurement to be Mn 71,000, Mw 111,000, and Mw / Mn 1.56. １ From H-NMR, the proportion of polymer (P1) in polymer 8 was calculated to be 95 mol %, and the proportion of polymer (P2) was calculated to be 5 mol %.

[0094] Example 13 (Production of Polymer 9) Polymer 9 was obtained by the same procedure as in Example 12, except that the amount of Bz-II was changed to 2.30 g and the amount of Bz-I was changed to 0.17 g. The molecular weight properties of Polymer 9 were determined by GPC measurement to be Mn 71,000, Mw 112,000, and Mw / Mn 1.58. １ From H-NMR, the proportion of polymer (P1) in polymer 9 was calculated to be 89 mol %, and the proportion of polymer (P2) was calculated to be 11 mol %.

[0095] Example 14 (Production of Polymer 10) Polymer 10 was obtained by the same procedure as in Example 12, except that the amount of Bz-II was changed to 2.17 g and the amount of Bz-I was changed to 0.25 g. The molecular weight properties of Polymer 10 were determined by GPC measurement to be Mn 72,000, Mw 114,000, and Mw / Mn 1.58. １ From H-NMR, the proportion of polymer (P1) in polymer 10 was calculated to be 85 mol %, and the proportion of polymer (P2) was calculated to be 15 mol %.

[0096] Example 15 (Production of Polymer 11) Polymer 11 was obtained by the same procedure as in Example 12, except that the amount of Bz-II was changed to 2.04 g and the amount of Bz-I was changed to 0.33 g. The molecular weight properties of Polymer 11 were determined by GPC measurement to be Mn 72,000, Mw 115,000, and Mw / Mn 1.60. １ From H-NMR, the proportion of polymer (P1) in polymer 11 was calculated to be 80 mol %, and the proportion of polymer (P2) was calculated to be 20 mol %.

[0097] Comparative Example 3 (Production of Polymer 12) Polymer 12 was obtained by the same procedure as in Example 12, except that the amount of Bz-II was changed to 1.91 g and the amount of Bz-I was changed to 0.41 g. The molecular weight properties of Polymer 12 were determined by GPC measurement to be Mn 72,000, Mw 119,000, and Mw / Mn 1.65. １ From H-NMR, the proportion of polymer (P1) in polymer 12 was calculated to be 76 mol %, and the proportion of polymer (P2) was calculated to be 24 mol %.

[0098]

[0099] Example 16 (Production of Polymer 13) Polymer 7 (71.0 g), ABN-E (0.13 g), styrene (hereinafter also referred to as "St") (11.0 g), N-phenylmaleimide (hereinafter also referred to as "PhMI") (18.0 g), and anisole (100 g) were charged into a 500 mL flask equipped with a stirrer and a thermometer, and the mixture was thoroughly degassed by nitrogen bubbling, and polymerization was initiated in a constant temperature bath at 70°C. After 4 hours, the mixture was cooled to room temperature to terminate the reaction. The polymerization solution was purified by reprecipitation from methanol and vacuum dried to obtain Polymer 13. The molecular weight properties of the obtained Polymer 13 were determined by GPC measurement to be Mn 100,000, Mw 160,000, and Mw / Mn 1.60.

[0100] Example 17 (Production of Polymer 14) The same procedure as in Example 16 was carried out, except that Polymer 7 was changed to Polymer 8 (71.0 g), to obtain Polymer 14. The molecular weight properties of Polymer 14 were determined by GPC measurement to be Mn 101,000, Mw 163,000, and Mw / Mn 1.61.

[0101] Example 18 (Production of Polymer 15) The same procedure as in Example 16 was carried out, except that Polymer 7 was changed to Polymer 9 (71.0 g), to obtain Polymer 15. The molecular weight properties of Polymer 15 were determined by GPC measurement to be Mn 101,000, Mw 166,000, and Mw / Mn 1.64.

[0102] Example 19 (Production of Polymer 16) The same procedure as in Example 16 was carried out, except that Polymer 7 was changed to Polymer 10 (72.0 g), to obtain Polymer 16. The molecular weight properties of Polymer 16 were determined by GPC measurement to be Mn 102,000, Mw 169,000, and Mw / Mn 1.66.

[0103] Example 20 (Production of Polymer 17) The same procedure as in Example 16 was carried out, except that Polymer 7 was changed to Polymer 11 (72.0 g), to obtain Polymer 17. The molecular weight properties of Polymer 17 were determined by GPC measurement to be Mn 102,000, Mw 173,000, and Mw / Mn 1.70.

[0104] Comparative Example 4 (Production of Polymer 18) The same procedure as in Example 16 was carried out, except that Polymer 7 was changed to Polymer 12 (72.0 g), to obtain Polymer 18. The molecular weight properties of Polymer 18 were determined by GPC measurement to be Mn 102,000, Mw 175,000, and Mw / Mn 1.72.

[0105]

[0106] 3. Evaluation (1) Evaluation of Modified Products and Their Cured Products [Experimental Examples 1 to 5, Comparative Experimental Example 1] <Flowability of Modified Products> For each of the modified products (Modified Products 1 to 6) of Examples 6 to 10 and Comparative Example 2, the E-type viscosity was measured using a TVE-20H viscometer (cone / plate type, manufactured by Toki Sangyo Co., Ltd.) under the following conditions. ○ Measurement conditions Cone shape: angle 3°, radius 7.7 mm Furthermore, the flowability was evaluated based on the viscosity of each of Modified Products 1 to 6 according to the following criteria: ◎: Less than 250 Pa s ○: 250 Pa s or more and less than 300 Pa s △: 300 Pa s or more and less than 400 Pa s ×: 400 Pa s or more

[0107] <Tensile Properties of Cured Modified Products> 100 parts by mass of each modified product (modified products 1 to 6) was mixed and stirred with 1 part by mass of water and 1 part by mass of dibutyltin dimethoxide, and the mixture was poured into a 2 mm thick mold. The mixture was degassed at room temperature using a vacuum oven and then heat-cured at 50°C for 2 days, yielding a uniform rubber-like cured product sheet. Using the resulting sheet as a sample, the tensile strength and elongation at break at room temperature (25°C) were measured in accordance with JIS K 6251, and the tensile product was calculated using the following formula: Tensile product (MPa·%) = Breaking strength (MPa) × Breaking elongation (%). Mechanical properties were evaluated from the calculated tensile product according to the following criteria: ◎: 130 MPa·% or more; ○: 125 MPa·% or more but less than 130 MPa·%; △: 110 MPa·% or more but less than 125 MPa·%; ×: Less than 110 MPa·%.

[0108] <Restoration Rate of Cured Modified Products> 100 parts by mass of each modified product (modified products 1 to 6) was mixed and stirred with 1 part by mass of water and 1 part by mass of dibutyltin dimethoxide, and the mixture was poured into a 2 mm thick mold. The mixture was degassed at room temperature using a vacuum oven and then heat-cured at 50°C for 2 days to obtain a uniform rubber-like cured product sheet. A dumbbell for tensile testing (JIS K 6251 Type 3) was prepared from the obtained sheet and used as a test specimen. Using a tensile tester (Autograph AGS-J, manufactured by Shimadzu Corporation), the test specimen was elongated at a rate of 5 mm / min to a gauge length of 32 mm (dumbbell Type 2: 20 mm) and held for 24 hours. Next, the test specimen was removed from the tensile tester and placed on a 2 mm thick Teflon (registered trademark) sheet. After 1 hour, the gauge length (L ２ The measurement was carried out under an environment of 23°C and 50% RH. The restoration rate was calculated using the measured values ​​by the following formula (1): Restoration rate [%] = (L １ -L ２ ) / (L １ -L ０ ) × 100 ... (1) where L ０ L: Gauge distance before extension [mm] １ : Gauge distance when extended [mm] L ２ L: Gauge distance [mm] 1 hour after removal from the tensile tester ０ = 20 [mm], L １= 32 [mm]. The recovery rate was evaluated based on the calculation results of the recovery rate of each test piece according to the following criteria. The higher the recovery rate, the higher the rubber elasticity of the vinyl polymer can be evaluated. ◎: 70% or more ○: 60% or more but less than 70% △: 50% or more but less than 60% ×: Less than 50%

[0109]

[0110] As is clear from the results in Table 5, by producing telechelic polymers (modified products 1 to 5) using polymers 1 to 5 in which the content of polymer (P2) was 20 mol% or less relative to the total amount of polymer (P1) and polymer (P2), cured products with excellent mechanical properties and recovery properties could be obtained. In addition, modified products 1 to 5 obtained from polymers 1 to 5 also had excellent fluidity. In contrast, when a telechelic polymer (modified product 6) was produced using polymer 6 in which the content of polymer (P2) relative to the total amount of polymer (P1) and polymer (P2) was greater than 20 mol%, the fluidity of modified product 6 was low, and the mechanical properties and recovery properties of the cured product formed using modified product 6 were inferior to those of modified products 1 to 5.

[0111] (2) Evaluation of Block Copolymers and Molded Products Thereof [Experimental Examples 6 to 10, Comparative Experimental Example 2] <Fluidity of Block Copolymers> For each of the block copolymers (polymers 13 to 18) of Examples 16 to 20 and Comparative Example 4, the E-type viscosity was measured using a TVE-20H viscometer (cone / plate type, manufactured by Toki Sangyo Co., Ltd.) under the following conditions. Measurement conditions: Cone shape: angle 3°, radius 7.7 mm. Furthermore, the fluidity of each block copolymer (polymers 13 to 18) was evaluated based on its viscosity using the following criteria: ◎: Less than 700 Pa s ○: 700 Pa s or more and less than 750 Pa s △: 750 Pa s or more and less than 850 Pa s ×: 850 Pa s or more

[0112] <Tensile Properties of Block Copolymers> 100 parts of each block copolymer (polymers 13 to 18) was dissolved in tetrahydrofuran (THF) to prepare a solution with a polymer concentration of 10%. This was poured into a mold, and the THF was evaporated to dryness to prepare a cast film with a thickness of approximately 1 mm. Using the film obtained as a sample, the tensile strength at break and elongation at break at room temperature (25°C) were measured in accordance with JIS K 6251, and the tensile product was calculated using the following formula: Tensile product (MPa·%) = Breaking strength (MPa) × Breaking elongation (%). The mechanical properties were evaluated from the calculated tensile product using the following criteria: ◎: 9,000 MPa·% or more ○: 8,500 MPa·% or more but less than 9,000 MPa·% △: 8,000 MPa·% or more but less than 8,500 MPa·% ×: Less than 8,000 MPa·%

[0113] <Restoration Rate of Block Copolymer> 100 parts of each block copolymer (polymers 13 to 18) was dissolved in tetrahydrofuran (THF) to prepare a solution with a polymer concentration of 10% by mass. This was poured into a mold, and the THF was evaporated to dryness to prepare a cast film with a thickness of approximately 2 mm. A dumbbell for tensile testing (JIS K 6251 Type 3) was prepared from the obtained film and used as a test specimen. Using a tensile tester (Autograph AGS-J, manufactured by Shimadzu Corporation), the test specimen was elongated at a rate of 5 mm / min so that the gauge length (dumbbell Type 2: 20 mm) became 32 mm, and held for 24 hours. Next, the test specimen removed from the tensile tester was placed on a 2 mm thick Teflon (registered trademark) sheet, and after 1 hour, the gauge length (L ２ The measurement was carried out in an environment of 23°C and 50% RH. Using the measured values, the restoration rate was calculated by the above formula (1) in the same manner as for the modified cured product. ０ = 20 [mm], L １ = 32 [mm]. Furthermore, the recovery rate was evaluated based on the calculation results of the recovery rate of each test piece according to the following criteria: ◎: 60% or more ○: 50% or more and less than 60% △: 40% or more and less than 50% ×: Less than 40%

[0114]

[0115] As is clear from the results in Table 6, by producing block copolymers (polymers 13-17) using polymers 7-11, in which the content of polymer (P2) was 20 mol% or less relative to the total amount of polymer (P1) and polymer (P2), molded articles with excellent mechanical properties and recovery were obtained. Furthermore, polymers 13-17 obtained from polymers 7-11 also had excellent fluidity. In contrast, when block copolymer (polymer 18) was produced using polymer 12, in which the content of polymer (P2) was greater than 20 mol% relative to the total amount of polymer (P1) and polymer (P2), the fluidity of polymer 18 was low, and the mechanical properties and recovery of molded articles of polymer 18 were inferior to those of polymers 13-17.

[0116] The present invention is not limited to the above-described embodiments, and encompasses various modifications and equivalent modifications within the scope of the spirit of the present invention. Therefore, in light of the above teachings, various combinations and forms, as well as other combinations and forms including only one element, more than one element, or less than one element, are to be understood as falling within the scope and spirit of the present invention.

Claims

1. A vinyl polymer containing a polymer (P1) represented by the following formula (1), wherein the ratio of the polymer (P2) to the total amount of the polymer (P1) and the polymer (P2) represented by the following formula (2) is 20 mol% or less. I-A １ -R １ -A ２ -I...(1) I-A １ -R １ -A ２ -X １ ...(2) (In formula (1) and formula (2), A １ represents a polymer chain having a structural unit derived from a vinyl monomer, and A ２ represents a single bond or a polymer chain having a structural unit derived from a vinyl monomer. R １ is a residue obtained by removing two iodine atoms of a bifunctional iodine-based polymerization control agent, and X １ is a hydrogen atom or a monovalent group having no iodine. However, R １ in formula (1) and R １ in formula (2) are the same group.) 2. The vinyl polymer according to claim 1, wherein the vinyl monomer contains a (meth)acrylic compound.

3. A method for producing a vinyl polymer by living radical polymerization, comprising a polymerization step of polymerizing a vinyl monomer in the presence of an iodine-based polymerization controller, wherein the iodine-based polymerization controller contains a compound (R1) which is a bifunctional iodine-based polymerization controller and optionally contains a compound (R2) represented by the following formula (4), and the ratio of the compound (R2) to the total amount of the compound (R1) and the compound (R2) is 20 mol% or less. A method for producing a vinyl polymer. I-R １ -X １ ...(4) (In formula (4), R １ is a residue obtained by removing two iodine atoms that the compound (R1) has, and X １ is a hydrogen atom or a monovalent group having no iodine.) 4. The polymerization step is a step of obtaining an iodinated vinyl polymer having iodine at the terminal by polymerizing the vinyl monomer, and reacting the iodinated vinyl polymer with a compound having a first functional group reactive with iodine and a second functional group different from the first functional group, The method for producing a vinyl polymer according to claim 3, further comprising a reaction step of obtaining a polymer having the second functional group at the terminal.

5. The vinyl polymer is a BAB block copolymer having a polymer block (A) and a polymer block (B), and the polymerization step is a step of obtaining the polymer block (A) by polymerizing a vinyl monomer constituting the polymer block (A). The method for producing a vinyl polymer according to claim 3, further comprising a step of polymerizing a monomer constituting the polymer block (B) in the presence of the polymer block (A) obtained by the polymerization step to obtain the BAB block copolymer.

Images