JP7081134B2 - Method for producing block copolymer - Google Patents

Description

The present invention relates to a method for producing a block copolymer.

Conventionally, a radical polymerization method is well known as a method for polymerizing a vinyl monomer to obtain a vinyl polymer, but it is generally said that it is difficult to control the molecular weight of the obtained vinyl polymer by the radical polymerization method. There were drawbacks. Further, the obtained vinyl polymer becomes a mixture of compounds having various molecular weights, and there is a drawback that it is difficult to obtain a vinyl polymer having a narrow molecular weight distribution. Specifically, even if the reaction was controlled, the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) could be reduced only to about 2 to 3.

As a method for eliminating such a defect, a living radical polymerization method has been developed since around 1990. That is, according to the living radical polymerization method, it is possible to control the molecular weight and obtain a polymer having a narrow molecular weight distribution. Specifically, since it is possible to easily obtain a polymer having Mw / Mn of 2 or less, it is in the limelight as a method for producing a polymer used in cutting-edge fields such as nanotechnology.

The living radical polymerization method includes an atom transfer radical polymerization method (ATRP method), a nitroxy radical method (NMP method), and a reversible addition-cleavage chain transfer polymerization method (RAFT method) which is a living radical polymerization of an exchange chain mechanism. ), Polymerization method using an organic telluric compound (TERP method), polymerization method using an organic antimony compound (SBRP method), polymerization method using an organic bismuth compound (BIRP method), iodine transfer polymerization method and various other polymerization methods are known. ing.

Among these, the ATRP method, the NMP method and the RAFT method are industrially used from the viewpoint of controllability of polymerization and ease of implementation.

Patent Document 1 describes a method for producing a (meth) acrylic block copolymer by the ATRP method using a metal complex having copper as a central metal as a catalyst, in which the conversion rate of the acrylic monomer is 80 to 95%. At the time point, a method for producing a block copolymer containing a methacrylic polymer block and an acrylic polymer block, which comprises adding and polymerizing a methacrylic monomer, is disclosed. Patent Documents 2 to 3 disclose a method for removing a metal complex such as copper used as a catalyst as a method for producing a (meth) acrylic block copolymer by the ATRP method.

Further, Patent Document 4 describes a methacrylic copolymer block (A) and an acrylic copolymer as a method for producing a (meth) acrylic block polymer by the RAFT method, which is a living radical polymerization method having an exchange chain mechanism. It is a block polymer containing one or more coalesced blocks (B), and the methacrylic copolymer (A) is a repeating unit derived from a methacrylate monomer and two types of N-substituted maleimides. Production of an acrylic thermoplastic resin, which is a random copolymer block containing a repeating unit derived from a weight, and the acrylic copolymer block (B) contains a repeating unit derived from an acrylic acid ester monomer. The method is disclosed.

Japanese Unexamined Patent Publication No. 2001-200026 Japanese Unexamined Patent Publication No. 2001-323014 Japanese Unexamined Patent Publication No. 11-193307 Japanese Unexamined Patent Publication No. 2014-12782

However, in the composition containing the block copolymer obtained by the ATRP method described in Patent Document 1, the copper remaining in the block copolymer acts as a catalyst and promotes the decomposition of the polymer chain at high temperature. Therefore, it cannot be used in applications that require strict heat resistance, for example, in-vehicle applications, because the heat resistance may not be sufficiently satisfied.
Further, the method described in Patent Documents 2 to 3 for removing the copper catalyst from the block copolymer obtained by the ATRP method can improve the heat resistance of the block copolymer, but increases the manufacturing process, so that the productivity is increased. There was a problem that it was inferior to.

On the other hand, the thermoplastic elastomer composition containing the block copolymer according to the RAFT method described in Patent Document 4 exhibits good heat resistance and oil resistance, and is under severe conditions from the viewpoint of heat resistance and oil resistance. It could withstand the application. However, in the examples, when obtaining a block copolymer having a methacrylic copolymer block (A) and an acrylic copolymer block (B), first, an acrylic polymer block (B) is obtained. Since the methacrylic copolymer block (A) is obtained after reprecipitation and purification using a poor solvent, there is a problem that the productivity is very poor.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for producing a block copolymer having excellent productivity and heat resistance. Further, it is to provide a method for producing a block copolymer suitably used as an elastomer material.

As a result of diligent studies to solve the above problems, the present inventors have obtained a polymer block having a glass transition temperature (Tg) of 25 ° C. or higher by a living radical polymerization method or an NMP method having a copper-free exchange chain mechanism. A) and the acrylic monomer (b) constituting the acrylic polymer block (B) in producing a block polymer having an acrylic polymer block (B) having a Tg of less than 25 ° C. Was polymerized to a conversion rate of 83 to 98% to obtain the acrylic polymer block (B), and then the monomer (а) constituting the polymer block (A) was added and polymerized. Therefore, they have found that by obtaining the polymer block (A), a block copolymer having excellent heat resistance can be produced with high productivity, and the present invention has been completed.

The present invention is as follows.
[1] A method for producing a block copolymer by a living radical polymerization method having an exchange chain mechanism.
The block copolymer has a polymer block (A) having a Tg of 25 ° C. or higher and an acrylic polymer block (B) having a Tg of less than 25 ° C.
A step of polymerizing the acrylic monomer (b) constituting the acrylic polymer block (B) to a conversion rate of 83 to 98% to obtain the acrylic polymer block (B).
Next, a method for producing a block copolymer, which comprises a step of adding a monomer (а) constituting the polymer block (A) and polymerizing the polymer block (A) to obtain the polymer block (A).
[2] A method for producing a block copolymer by the nitroxy radical method (NMP method).
The block copolymer has a polymer block (A) having a Tg of 25 ° C. or higher and an acrylic polymer block (B) having a Tg of less than 25 ° C.
A step of polymerizing the acrylic monomer (b) constituting the acrylic polymer block (B) to a conversion rate of 83 to 98% to obtain the acrylic polymer block (B).
Next, a method for producing a block copolymer, which comprises a step of adding a monomer (а) constituting the polymer block (A) and polymerizing the polymer block (A) to obtain the polymer block (A).
[3] The method for producing a block copolymer according to [1] or [2], wherein the Tg of the polymer block (A) is 150 ° C. or higher.
[4] As the polymerization solvent, a solvent containing at least one selected from the group consisting of a nitrile solvent, an aromatic solvent, a ketone solvent, an ester solvent and an orthoester solvent is used. 1] The method for producing a block copolymer according to any one of [3].
[5] Any one of [1] to [4], wherein the initial concentration of the acrylic monomer (b) when obtaining the acrylic polymer block (B) is 2,500 mM or more. The method for producing a block copolymer according to.
[6] As the first polymerization step, the acrylic monomer (b) is polymerized to a conversion rate of 83 to 98% using a polyfunctional polymerization control agent, and the acrylic polymer block (B) is polymerized. And the process of obtaining
Next, according to any one of [1] to [5], the second polymerization step includes a step of adding the monomer (а) and polymerizing it to obtain the polymer block (A). A method for producing a block copolymer.
[7] As the first polymerization step, a step of polymerizing the monomer (а) to obtain the polymer block (A), and a step of obtaining the polymer block (A).
Next, as a second polymerization step, the acrylic monomer (b) is added and polymerized to a conversion rate of 83 to 98% to obtain the acrylic polymer block (B).
The third polymerization step is described in any one of [1] to [5], which comprises a step of adding the monomer (а) and polymerizing the polymer block (A) to obtain the polymer block (A). A method for producing a block copolymer.
[8] Of [1] to [7], the block copolymer has a polymer block (A) containing structural units derived from styrenes and maleimide compounds, and an acrylic polymer block (B). The method for producing a block copolymer according to any one.
[9] The method for producing a block copolymer according to any one of [1] to [8], wherein the block copolymer is applied as an elastomer material.
[10] The method for producing a block copolymer according to any one of [1] to [8], wherein the block copolymer is used as an elastomer material for automobiles to produce a block copolymer. Method.

According to the method for producing a block copolymer disclosed in the present specification, a block copolymer having excellent heat resistance can be obtained with high productivity. Further, it is possible to obtain a block copolymer preferably used as an elastomer material.

Hereinafter, various embodiments of the techniques disclosed in the present specification will be described in detail. In addition, in this specification, "(meth) acrylic" means acrylic and methacrylic, and "(meth) acrylate" means acrylate and methacrylate. Further, the “(meth) acryloyl group” means an acryloyl group and a methacryloyl group.

The block copolymer disclosed in the present specification includes a polymer block (A) having a glass transition temperature (Tg) of 25 ° C. or higher (hereinafter, simply referred to as “polymer block (A)”) and Tg. Each has one or more acrylic polymer blocks (B) below 25 ° C. (hereinafter, simply referred to as “polymer block (B)”). When the block copolymer has two or more of the polymer blocks (A) and / or the polymer blocks (B), the structures of the blocks may be the same or different.

Hereinafter, a block copolymer having a polymer block (A), a polymer block (B), a polymer block (A) and a polymer block (B), a method for producing the block copolymer, and uses thereof will be described. ..

1. 1. Polymer block (A)
The polymer block (A) is a polymer block having a Tg of 25 ° C. or higher.
Examples of the monomer (а) constituting the polymer block (A) include styrenes, maleimide compounds, (meth) acrylic acid alkyl ester compounds, amide group-containing vinyl compounds, and the like. Species or two or more species can be used.

Examples of the styrenes include styrene and its derivatives.
Specific examples of the styrene derivative include α-methylstyrene, β-methylstyrene, vinyltoluene, vinylxylene, vinylnaphthalene, o-methylstyrene, m-methylstyrene, p-methylstyrene, o-ethylstyrene, and m-ethyl. Styrene, p-ethylstyrene, pn-butylstyrene, p-isobutylstyrene, pt-butylstyrene, o-methoxystyrene, m-methoxystyrene, p-methoxystyrene, o-chloromethylstyrene, p-chloro Examples thereof include methylstyrene, o-chlorostyrene, p-chlorostyrene, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, divinylbenzene and the like, and one or more of these can be used. .. By polymerizing a monomer containing styrenes, a structural unit derived from styrenes can be introduced into the polymer block (A).
Among the above, styrene, o-methoxystyrene, m-methoxystyrene, p-methoxystyrene, o-hydroxystyrene, m-hydroxystyrene, and p-hydroxystyrene are preferable from the viewpoint of polymerizable property. Further, α-methylstyrene, β-methylstyrene and vinylnaphthalene are preferable in that the Tg of the polymer block (A) can be increased and a block polymer having excellent heat resistance can be obtained.

In the polymer block (A), the ratio of the structural units derived from the styrenes is preferably 1% by mass or more and 70% by mass or less with respect to all the structural units of the polymer block (A). It is more preferably 5% by mass or more and 70% by mass or less, further preferably 10% by mass or more and 70% by mass or less, and further preferably 20% by mass or more and 60% by mass or less. Further, for example, it may be 20% by mass or more and 40% by mass or less.
When the structural unit derived from styrenes is 1% by mass or more, a block copolymer having excellent moldability can be obtained. On the other hand, if it is 70% by mass or less, the required amount of the structural unit derived from the maleimide compound described later can be secured, so that a block copolymer having excellent heat resistance and oil resistance can be obtained.

〔式中、Ｒ¹は水素、炭素数１～３のアルキル基又はＰｈＲ²を表す。ただし、Ｐｈはフェニル基を表し、Ｒ²は水素、ヒドロキシ基、炭素数１～２のアルコキシ基、アセチル基又はハロゲンを表す。〕 Examples of the maleimide compound include maleimide and N-substituted maleimide compounds.
Specific examples of the N-substituted maleimide compound include, for example, N-methylmaleimide, N-ethylmaleimide, Nn-propylmaleimide, N-isopropylmaleimide, Nn-butylmaleimide, N-isobutylmaleimide, and N-tert. -N-alkyl-substituted maleimide compounds such as butylmaleimide, N-pentylmaleimide, N-hexylmaleimide, N-heptylmaleimide, N-octylmaleimide, N-laurylmaleimide, N-stearylmaleimide; N-cyclopentylmaleimide, N-cyclohexyl N-Cycloalkyl-substituted maleimide compounds such as maleimide; N-phenylmaleimide, N- (4-hydroxyphenyl) maleimide, N- (4-acetylphenyl) maleimide, N- (4-methoxyphenyl) maleimide, N- (4) Examples thereof include N-aryl substituted maleimide compounds such as -ethoxyphenyl) maleimide, N- (4-chlorophenyl) maleimide, N- (4-bromophenyl) maleimide, and N-benzylmaleimide, and one or two of these. More than a seed can be used. By polymerizing the monomer containing the maleimide compound, the structural unit derived from the maleimide compound can be introduced into the polymer block (A).
Among the above, the compound represented by the following general formula (1) is preferable in that the obtained block copolymer has more excellent oil resistance.

[In the formula, R ¹ represents hydrogen, an alkyl group having 1 to 3 carbon atoms or PhR ² . However, Ph represents a phenyl group, and R ² represents a hydrogen, a hydroxy group, an alkoxy group having 1 to 2 carbon atoms, an acetyl group or a halogen. ]

In the polymer block (A), the ratio of the structural units derived from the maleimide compound is preferably 30% by mass or more and 99% by mass or less with respect to all the structural units of the polymer block (A). It is more preferably 30% by mass or more and 95% by mass or less, further preferably 30% by mass or more and 90% by mass or less, and further preferably 40% by mass or more and 80% by mass or less. Further, for example, it may be 50% by mass or more, and further, for example, 60% by mass or more. Further, for example, it may be 75% by mass or less, and further, for example, it may be 70% by mass or less. Further, for example, it may be 50% by mass or more and 75% by mass or less, or 60% by mass or more and 70% by mass or less.
When the structural unit derived from the maleimide compound is 30% by mass or more, the obtained block copolymer is excellent in heat resistance and oil resistance. On the other hand, when it is 99% by mass or less, it has a structural unit other than the structural unit derived from the maleimide compound, and as a result, it is excellent in fluidity and moldability.

Specific examples of the above (meth) acrylic acid alkyl ester compound include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate and methacryl. Linear or branched methacrylic acid such as hexyl acid, 2-ethylhexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, n-nonyl methacrylate, isononyl methacrylate, decyl methacrylate and dodecyl methacrylate. Alkyl methacrylic acid ester compounds; cyclohexyl methacrylate, methyl cyclohexyl methacrylate, tert-butyl cyclohexyl methacrylate, cyclododecyl methacrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, dicyclopentenyl (meth) acrylate. , (Meta) Acrylic acid Dicyclopentanyl or the like, an aliphatic cyclic ester compound of acrylic acid and the like can be mentioned.

Specific examples of the amide group-containing vinyl compound include (meth) acrylamide, tert-butyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, and N-isopropyl. (Meta) acrylamide derivatives such as (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide and (meth) acryloylmorpholin; and N such as N-vinylacetamide, N-vinylformamide and N-vinylisobutylamide. -Examples include vinylamide-based monomers.

Further, when the polymer block (A) contains a crosslinkable functional group, it is preferable because it is easy to obtain a block copolymer having a small compression set. The crosslinkable functional group may be introduced by using, for example, styrenes having a functional group such as a hydroxy group and / or a maleimide compound, or by copolymerizing a vinyl compound having a crosslinkable functional group. Can be done. Examples of the vinyl compound having a crosslinkable functional group include unsaturated carboxylic acid, unsaturated acid anhydride, hydroxy group-containing vinyl compound, epoxy group-containing vinyl compound, primary or secondary amino group-containing vinyl compound, and reactive silicon group. Examples include compounds. These compounds may be used alone or in combination of two or more.

Specific examples of unsaturated carboxylic acids include (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, cinnamic acid, and monoalkyl esters of unsaturated dicarboxylic acids (maleic acid, fumal). Monoalkyl esters such as acids, itaconic acid, citraconic acid, maleic anhydride, itaconic anhydride, and citraconic anhydride) and the like can be mentioned. These compounds may be used alone or in combination of two or more.

Specific examples of the unsaturated acid anhydride include maleic anhydride, itaconic anhydride, citraconic anhydride and the like. These compounds may be used alone or in combination of two or more.

Specific examples of the hydroxy group-containing vinyl compound include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate. , 3-Hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and mono (meth) acrylic acid esters of polyalkylene glycols such as polyethylene glycol and polypropylene glycol. These compounds may be used alone or in combination of two or more.

Specific examples of the epoxy group-containing vinyl compound include glycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and 3,4-epoxycyclohexylmethyl (meth) acrylate. These compounds may be used alone or in combination of two or more.

Specific examples of the primary or secondary amino group-containing vinyl compound include aminoethyl (meth) acrylate, aminopropyl (meth) acrylate, N-methylaminoethyl (meth) acrylate, N-ethylaminoethyl (meth) acrylate and the like. Amino group-containing (meth) acrylic acid ester; containing amino groups such as aminoethyl (meth) acrylamide, aminopropyl (meth) acrylamide, N-methylaminoethyl (meth) acrylamide, and N-ethylaminoethyl (meth) acrylamide ( Meta) acrylamide and the like can be mentioned.

Specific examples of the reactive silicon group-containing compound include vinylsilanes such as vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, and vinyldimethylmethoxysilanen; (meth) trimethoxysilylpropyl acrylate, (meth). Cyril group-containing (meth) acrylic acid esters such as triethoxysilylpropyl acrylate, methyldimethoxysilylpropyl (meth) acrylate, and dimethylmethoxysilylpropyl (meth) acrylate; silyl group-containing vinyl ethers such as trimethoxysilylpropyl vinyl ether. Kind: Cyril group-containing vinyl esters such as trimethoxysilyl undecanoate vinyl and the like can be mentioned. These compounds may be used alone or in combination of two or more.

In addition to the above, an oxazoline group or an isocyanate group can be introduced as a crosslinkable functional group by copolymerizing an oxazoline group-containing monomer or an isocyanate group-containing monomer.

Further, by copolymerizing a polyfunctional polymerizable monomer having two or more polymerizable unsaturated groups in the molecule, a polymerizable unsaturated group is introduced into the polymer block (A) as a crosslinkable functional group. obtain. The polyfunctional polymerizable monomer is a compound having two or more polymerizable functional groups such as a (meth) acryloyl group and an alkenyl group in the molecule, and is a polyfunctional (meth) acrylate compound, a polyfunctional alkenyl compound, and the like. Examples thereof include compounds having both a (meth) acryloyl group and an alkenyl group. Among the above, allyl (meth) acrylate, isopropenyl (meth) acrylate, butenyl (meth) acrylate, pentenyl (meth) acrylate, 2- (2-vinyloxyethoxy) ethyl (meth) acrylate and the like When a compound having both a (meth) acryloyl group and an alkenyl group in the molecule is used, there is a difference in the reactivity of the polymerizable unsaturated group, so that the polymer block (A) is effectively a polymerizable unsaturated group. It is preferable in that it can be introduced. These compounds may be used alone or in combination of two or more.

When the polymer block (A) has a crosslinkable functional group, the amount of the crosslinkable functional group introduced is preferably 0.01 mol% or more based on the total structural units of the polymer block (A), and more. It is preferably 0.1 mol% or more, more preferably 1.0 mol% or more, and particularly preferably 2.0 mol% or more. When the amount of the crosslinkable functional group introduced is 0.01 mol% or more, it becomes easy to obtain a block copolymer having a small compression set. On the other hand, from the viewpoint of controllability of the cross-linking reaction, the upper limit of the amount of the cross-linking functional group introduced is preferably 60 mol% or less, more preferably 40 mol% or less, still more preferably 20 mol% or less, and particularly. It is preferably 10 mol% or less. The amount of the crosslinkable functional group introduced can be in the range of 0.01 mol% or more and 60 mol% or less, preferably 0.1 mol% or more and 40 mol, based on the total structural units of the polymer block (A). % Or less, more preferably 1.0 mol% or more and 20 mol% or less.

As long as the Tg of the polymer block (A) can be 25 ° C. or higher, other monomers copolymerizable with these can be used in addition to the above-mentioned monomers. Examples of the other monomer include an acrylic monomer (b) described later, a methacrylic acid alkoxyalkyl ester compound, and the like. These compounds may be used alone or in combination of two or more.
In the polymer block (A), the ratio of the structural units derived from the other monomers is in the range of 0% by mass or more and 50% by mass or less with respect to all the structural units of the polymer block (A). Is preferable. It is more preferably 5% by mass or more and 45% by mass or less, and further preferably 10% by mass or more and 40% by mass or less.

Specific examples of the methacrylic acid alkoxyalkyl ester compound include methoxymethyl methacrylate, ethoxymethyl methacrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, n-propoxyethyl methacrylate, n-butoxyethyl methacrylate, and methoxypropyl methacrylate. , Ethoxypropyl methacrylate, n-propoxypropyl methacrylate, n-butoxypropyl methacrylate, methoxybutyl methacrylate, ethoxybutyl methacrylate, n-propoxybutyl methacrylate, n-butoxybutyl methacrylate and the like.

Examples of the monomer other than the above include N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate.

In the present disclosure, the Tg of the polymer constituting the polymer block (A) is 25 ° C. or higher, and from the viewpoint of heat resistance of the obtained block copolymer, 50 ° C. or higher is preferable, and 100 ° C. or higher is more preferable. It is more preferable that the temperature is 150 ° C. or higher. Since Tg can contribute to heat resistance, for example, it may be 170 ° C. or higher, 180 ° C. or higher, 190 ° C. or higher, or 200 ° C. or higher. Furthermore, it may be 210 ° C. or higher, 220 ° C. or higher, or 230 ° C. or higher. Due to the limitation of the constituent monomer units that can be used, the upper limit of Tg is 350 ° C. Tg may also be, for example, 280 ° C. or lower, 270 ° C. or lower, and further, for example, 260 ° C. or lower.
The Tg value can be obtained by differential scanning calorimetry (DSC) as described in Examples described later.

When the solubility parameter (SP value) of the polymer block (A) is 10.0 or more, it is preferable in that the oil resistance of the block copolymer becomes better. The SP value is more preferably 11.0 or more, further preferably 12.0 or more, still more preferably 13.0 or more.
The upper limit of the SP value of the polymer block (A) is not particularly limited, but is usually 30 or less. Further, for example, the SP value may be 20.0 or less, or may be, for example, 18.0 or less.

δ ：ＳＰ値（（ｃａｌ／ｃｍ³）^1/2）
ΔＥ_vap ：各原子団のモル蒸発熱（ｃａｌ／ｍｏｌ）
Ｖ ：各原子団のモル体積（ｃｍ³／ｍｏｌ） For the above SP value, refer to R.I. F. It can be calculated by the calculation method described in "Polymer Engineering and Science" 14 (2), 147 (1974) written by Fedors. Specifically, the calculation method shown in the equation (1) is used.

δ: SP value ((cal / cm ³ ) ^1/2 )
ΔE _vap : Molar heat of vaporization of each atomic group (cal / mol)
V: Molar volume of each atomic group (cm ³ / mol)

2. 2. Polymer block (B)
The polymer block (B) is an acrylic polymer block having a Tg of less than 25 ° C.
Examples of the acrylic monomer (b) constituting the polymer block (B) include an acrylic acid ester compound.

Specific examples of the acrylic acid ester compound include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, hexyl acrylate, and acrylic acid. Acrylic acid alkyl ester compounds such as 2-ethylhexyl, octyl acrylate, nonyl acrylate, decyl acrylate, lauryl acrylate, stearyl acrylate;
Aliphatic cyclic ester compounds of acrylic acid such as cyclohexyl acrylate, methyl cyclohexyl acrylate, tert-butyl cyclohexyl acrylate, cyclododecyl acrylate;
Methoxymethyl acrylate, ethoxymethyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, n-propoxyethyl acrylate, n-butoxyethyl acrylate, methoxypropyl acrylate, ethoxypropyl acrylate, n-propoxypropyl acrylate , Acrylic acid alkoxyalkyl ester compounds such as n-butoxypropyl acrylate, methoxybutyl acrylate, ethoxybutyl acrylate, n-propoxybutyl acrylate, n-butoxybutyl acrylate and the like. In addition to this, an acrylic acid ester compound having a functional group such as an amide group, an amino group, a carboxy group and a hydroxy group may be used. These compounds may be used alone or in combination of two or more.
Among the above, an acrylic acid alkyl ester compound having an alkyl group having 1 to 12 carbon atoms or an alkoxyalkyl group having 2 to 8 carbon atoms is preferable in that a block copolymer having excellent flexibility can be obtained. Further, from the viewpoint of heat resistance and oil resistance, the acrylic monomer (b) is an acrylic acid alkyl ester compound having an alkyl group having 1 to 3 carbon atoms or an alkoxyalkyl group having 2 to 3 carbon atoms. It is more preferable that it contains.

In the polymer block (B), the ratio of the structural units derived from the acrylic monomer (b) is in the range of 20% by mass or more and 100% by mass or less with respect to all the structural units of the polymer block (B). It is preferably 50% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, and further preferably 90% by mass or more and 100% by mass or less.
In the polymer block (B), when the structural unit derived from the acrylic monomer (b) is in the above range, a block copolymer having good mechanical properties tends to be obtained.

In addition to the acrylic monomer (b), other monomers copolymerizable with the acrylic monomer (b) can be used as long as the Tg of the polymer block (B) can be lower than 25 ° C. .. Examples of other monomers include the above-mentioned monomer (а), and aliphatic or aromatic vinyl compounds such as alkyl vinyl esters, alkyl vinyl ethers and styrenes.

In the present disclosure, the Tg of the polymer constituting the polymer block (B) is less than 25 ° C, preferably 20 ° C or lower. Further, for example, the temperature may be 10 ° C. or lower. The Tg is preferably 0 ° C. or lower, more preferably −10 ° C. or lower. When Tg is 25 ° C. or higher, the flexibility of the obtained block copolymer may be insufficient. Due to the limitation of the constituent monomer units that can be used, the lower limit of Tg is −80 ° C.
Further, when Tg is −20 ° C. or lower, flexibility is ensured even in a low temperature environment, which is preferable. When cold resistance is taken into consideration, it is more preferably −30 ° C. or lower, and further preferably −40 ° C. or lower.
The Tg value can be obtained by differential scanning calorimetry (DSC) as described in Examples described later.

Further, when the SP value of the polymer block (B) is 9.9 or more, it is preferable in that the oil resistance of the block copolymer becomes better. The SP value is more preferably 10.0 or more, further preferably 10.1 or more, and particularly preferably 10.2 or more.
The upper limit of the SP value of the polymer block (B) is not particularly limited, but is usually 20 or less.

Further, the polymer block (B) may contain a crosslinkable functional group, which is preferable because it is easy to obtain a block copolymer having high oil resistance. The introduction of the crosslinkable functional group can be carried out, for example, by copolymerizing a vinyl compound having a crosslinkable functional group. Examples of the vinyl compound having a crosslinkable functional group include unsaturated carboxylic acid, unsaturated acid anhydride, hydroxy group-containing vinyl compound, epoxy group-containing vinyl compound, primary or secondary amino group-containing vinyl compound, and reactive silicon group. Examples include compounds. These compounds may be used alone or in combination of two or more.
When the polymer block (B) has a crosslinkable functional group, the amount of the crosslinkable functional group introduced is preferably 0.01 mol% or more based on the total structural units of the polymer block (B), and more. It is preferably 0.1 mol% or more, and more preferably 0.5 mol% or more. When the amount of the crosslinkable functional group introduced is 0.01 mol% or more, it becomes easy to obtain a block copolymer having high oil resistance. On the other hand, from the viewpoint of flexibility, the upper limit of the amount of the crosslinkable functional group introduced is preferably 20 mol% or less, more preferably 10 mol% or less, still more preferably 5 mol% or less. The amount of the crosslinkable functional group introduced can be in the range of 0.01 mol% or more and 20 mol% or less, preferably 0.1 mol% or more and 10 mol, based on the total structural unit of the polymer block (B). % Or less, more preferably 0.5 mol% or more and 5 mol% or less.

3. 3. Block Copolymer with Polymer Block (A) and Polymer Block (B) The block copolymer of the present disclosure has one or more of the above-mentioned polymer block (A) and the above-mentioned polymer block (B), respectively. When the block copolymer has two or more polymer blocks (A) and / or polymer blocks (B), the structure of each block may be the same or different.
The structure of the block copolymer is also not particularly limited, and various linear or branched block copolymers such as AB type diblock polymer or ABA type and ABC type triblock polymers can be used. In terms of obtaining good performance as an elastomer material, it is an A- (BA) n-type such as an ABA triblock copolymer composed of a polymer block (A) -polymer block (B) -polymer block (A). Those having a structure are preferable.

In the block copolymer, the polymer block (A) acts as a hard segment and the polymer block (B) acts as a soft segment. As a result, the block copolymer of the present disclosure exhibits excellent mechanical properties such as breaking elongation and breaking strength, and becomes a useful material as an elastomer.
The proportion of the polymer block (A) in the block copolymer is preferably 10% by mass or more and 60% by mass or less, and more preferably 20% by mass or more and 50% by mass or less.
The proportion of the polymer block (B) in the block copolymer is preferably 40% by mass or more and 90% by mass or less, and more preferably 50% by mass or more and 80% by mass or less.

When the block copolymer of the present disclosure is used as an elastomer material, it is preferable that the SP value of the polymer block (A) and the SP value of the polymer block (B) have a difference of 0.1 or more. When the SP values differ by 0.1 or more, both of them are appropriately phase-separated in the block copolymer, so that it is possible to exhibit excellent mechanical strength performance. The difference in SP value is more preferably 0.3 or more, further preferably 0.5 or more, further preferably 0.8 or more, and particularly preferably 1.0 or more. .. Further, from the viewpoint of manufacturing and the like, the difference in SP value is preferably 10 or less, more preferably 5.0 or less.

Further, when the block copolymer of the present disclosure is used as an elastomer material, it is preferable to have a polymer block (A) containing structural units derived from styrenes and a maleimide compound, and a polymer block (B).

Further, when the polymer block (A) has a crosslinkable functional group, an elastomer material having a smaller compression set can be obtained by cross-linking using the crosslinkable functional group. The cross-linking may be due to a reaction between the cross-linking functional groups introduced into the polymer block (A), or as described later, a cross-linking agent having a functional group capable of reacting with the cross-linking functional group is added. You may go there. In the case of a reaction between the crosslinkable functional groups introduced into the polymer block (A), if a reactive silicon group is used as the crosslinkable functional group, the polymerization reaction for producing the block copolymer and the subsequent crosslinking reaction are efficient. Can be done in a targeted manner.

The number average molecular weight (Mn) of the block copolymers of the present disclosure is preferably in the range of 10,000 or more and 500,000 or less. When the number average molecular weight is 10,000 or more, sufficient strength can be exhibited as an elastomer material. Further, if it is 500,000 or less, good moldability can be ensured. The number average molecular weight is more preferably in the range of 20,000 or more and 400,000 or less, and further preferably in the range of 50,000 or more and 200,000 or less.
Further, the molecular weight distribution (Mw / Mn) obtained by dividing the value of the weight average molecular weight (Mw) of the block copolymer by the value of the number average molecular weight (Mn) is 1.5 or less in terms of moldability. It is preferable to have. It is more preferably 1.4 or less, further preferably 1.3 or less, and even more preferably 1.2 or less. The lower limit of the molecular weight distribution is 1.0.

4. Method for Producing Block Copolymer Having Polymer Block (A) and Polymer Block (B) As a method for producing a block copolymer having the above-mentioned polymer block (A) and the above-mentioned polymer block (B) of the present disclosure. Is not particularly limited as long as it is a living radical polymerization method other than the atom transfer radical polymerization method (ATRP method), and is a reversible addition-cleaving chain transfer polymerization method (RAFT method). , A polymerization method using an organic antimony compound (SBRP method), a polymerization method using an organic bismuth compound (BIRP method), a living radical polymerization method having an exchange chain mechanism such as an iodine transfer polymerization method, and a nitroxy radical method (NMP method). Various polymerization methods such as the above can be adopted. Among these, the RAFT method and the NMP method are preferable from the viewpoint of controllability of polymerization and ease of implementation.

As the living radical polymerization method and the NMP method of the exchange chain mechanism, any process such as a batch process, a semi-batch process, a dry continuous polymerization process, or a continuous stirring tank type process (CSPR) may be adopted. Further, the polymerization type can be applied to various aspects such as bulk polymerization using no solvent, solvent-based solution polymerization, aqueous emulsion polymerization, mini-emulsion polymerization or suspension polymerization.

In the RAFT method, controlled polymerization proceeds via a reversible chain transfer reaction in the presence of a specific polymerization control agent (RAFT agent) and a general free radical polymerization initiator. As the RAFT agent, various known RAFT agents such as a dithioester compound, a xanthate compound, a trithiocarbonate compound and a dithiocarbamate compound can be used.
As the RAFT agent, a monofunctional agent having only one active site may be used, or a bifunctional or more agent may be used. It is preferable to use a bifunctional RAFT agent from the viewpoint that it is easy to efficiently obtain the block copolymer having the A- (BA) n-type structure.
The amount of the RAFT agent used is appropriately adjusted depending on the monomer used, the type of the RAFT agent, and the like.

As the polymerization initiator used in the polymerization by the RAFT method, known radical polymerization initiators such as azo compounds, organic peroxides and persulfates can be used, but they are easy to handle for safety and are used during radical polymerization. Azo compounds are preferable because side reactions are unlikely to occur.
Specific examples of the above azo compound include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), and 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], 2,2'-azobis (N-butyl-2-methylpropionamide) and the like.
Only one kind of the radical polymerization initiator may be used, or two or more kinds thereof may be used in combination.

The ratio of the radical polymerization initiator used is not particularly limited, but from the viewpoint of obtaining a polymer having a smaller molecular weight distribution, the amount of the radical polymerization initiator used relative to 1 mol of the RAFT agent is preferably 0.5 mol or less, and is 0. It is more preferably .2 mol or less. Further, from the viewpoint of stably performing the polymerization reaction, the lower limit of the amount of the radical polymerization initiator used with respect to 1 mol of the RAFT agent is 0.01 mol. Therefore, the amount of the radical polymerization initiator used with respect to 1 mol of the RAFT agent is preferably in the range of 0.01 mol or more and 0.5 mol or less, and more preferably in the range of 0.05 mol or more and 0.2 mol or less.

The reaction temperature during the polymerization reaction by the RAFT method is preferably 40 ° C. or higher and 100 ° C. or lower, more preferably 45 ° C. or higher and 90 ° C. or lower, and further preferably 50 ° C. or higher and 80 ° C. or lower. When the reaction temperature is 40 ° C. or higher, the polymerization reaction can proceed smoothly. On the other hand, if the reaction temperature is 100 ° C. or lower, side reactions can be suppressed and restrictions on the initiators and solvents that can be used are relaxed.

｛式中、Ｒ¹は炭素数１～２のアルキル基又は水素原子であり、Ｒ²は炭素数１～２のアルキル基又はニトリル基であり、Ｒ³は－（ＣＨ₂）ｍ－、ｍは０～２であり、Ｒ⁴、Ｒ⁵は炭素数１～４のアルキル基である｝ In the NMP method, a specific alkoxyamine compound or the like having nitroxide is used as a living radical polymerization initiator, and the polymerization proceeds via the nitroxide radical derived from the specific alkoxyamine compound or the like. In the present disclosure, the type of nitroxido radical used is not particularly limited, but from the viewpoint of polymerization controllability when polymerizing a monomer containing an acrylate, a compound represented by the general formula (2) is used as the nitroxide compound. Is preferable.

{In the formula, R ¹ is an alkyl group or a hydrogen atom having 1 to 2 carbon atoms, R ² is an alkyl group or a nitrile group having 1 to 2 carbon atoms, and R ³ is- (CH ₂ ) m-, m. Is 0 to 2, and R ⁴ and R ⁵ are alkyl groups having 1 to 4 carbon atoms}.

The nitroxide compound represented by the general formula (2) undergoes a primary dissociation by heating at about 70 to 80 ° C. and causes an addition reaction with a vinyl-based monomer. At this time, it is possible to obtain a polyfunctional polymerization control agent by adding a nitroxide compound to a vinyl-based monomer having two or more vinyl groups. Next, the vinyl-based monomer can be polymerized in the living room by secondary dissociation of the polymerization control agent under heating.
In this case, since the control agent has two or more active sites in the molecule, a polymer having a narrower molecular weight distribution can be obtained. From the viewpoint of efficiently obtaining the block copolymer having the A- (BA) n-type structure, it is preferable to use a bifunctional polymerization control agent having two active sites in the molecule.
The amount of the nitroxide compound used is appropriately adjusted depending on the monomer used, the type of the nitroxide compound, and the like.

｛式中、Ｒ⁴、Ｒ⁵は炭素数１～４のアルキル基である。｝ When the block copolymer of the present disclosure is produced by the NMP method, 0.001 to 0.2 mol of the nitroxide radical represented by the general formula (3) is added to 1 mol of the nitroxide compound represented by the general formula (2). May be added in the range of the above to carry out the polymerization.

{In the formula, R ⁴ and R ⁵ are alkyl groups having 1 to 4 carbon atoms. }

By adding 0.001 mol or more of the nitroxide radical represented by the general formula (3), the time for the concentration of the nitroxide radical to reach a steady state is shortened. As a result, the polymerization can be controlled to a higher degree, and a polymer having a narrower molecular weight distribution can be obtained. On the other hand, if the amount of the nitroxide radical added is too large, the polymerization may not proceed. A more preferable amount of the nitroxide radical added to 1 mol of the nitroxide compound is in the range of 0.01 to 0.5 mol, and a more preferable amount of addition is in the range of 0.05 to 0.2 mol.

The reaction temperature in the NMP method is preferably 50 ° C. or higher and 140 ° C. or lower, more preferably 60 ° C. or higher and 130 ° C. or lower, further preferably 70 ° C. or higher and 120 ° C. or lower, and particularly preferably 80 ° C. or higher and 120 ° C. It is as follows. When the reaction temperature is 50 ° C. or higher, the polymerization reaction can proceed smoothly. On the other hand, if the reaction temperature is 140 ° C. or lower, side reactions such as radical chain transfer tend to be suppressed.

A- (BA) n of an ABA triblock copolymer composed of a polymer block (A) -polymer block (B) -polymer block (A) by the living radical polymerization method and the NMP method of the exchange chain mechanism. When obtaining a mold structure, for example, the target block copolymer may be obtained by sequentially polymerizing each block. In this case, first, as the first polymerization step, the above-mentioned monomer (а) is polymerized to obtain a polymer block (A). The conversion rate of the monomer (а) in the first polymerization step is preferably 70 to 99%.
Next, as the second polymerization step, the acrylic monomer (b) is added and polymerized to obtain a polymer block (B). The conversion rate of the acrylic monomer (b) in the second polymerization step is 83 to 98%, preferably 86 to 98%, in terms of excellent breaking elongation retention rate and breaking strength retention rate after the heat resistance test. , 90-98% is more preferred.
Further, as a third polymerization step, the above-mentioned monomer (а) is added and polymerized to obtain an ABA triblock copolymer. The conversion rate of the monomer (а) in the third polymerization step is preferably 50 to 99%.
In this case, it is preferable to use the above-mentioned monofunctional polymerization initiator or polymerization control agent as the polymerization initiator. By repeating the above-mentioned second polymerization step and third polymerization step, a higher-order block copolymer such as a tetrablock copolymer can be obtained.
The conversion rate of the monomer (a) and the acrylic monomer (b) can be obtained by gas chromatography measurement as described in Examples described later.
The initial concentration of the acrylic monomer (b) when the polymer block (B) is obtained in the second polymerization step is excellent in breaking elongation retention rate and breaking strength retention rate after the heat resistance test, and oil resistance. In that respect, 2,500 mM or more is preferable, and 2,800 mM or more is more preferable.

Further, when it is produced by a method including the following two-step polymerization steps, it is preferable because the target product can be obtained more efficiently. That is, first, as the first polymerization step, the acrylic monomer (b) is polymerized to obtain a polymer block (B). The conversion rate of the acrylic monomer (b) in the first polymerization step is 83 to 98%, preferably 86 to 98%, in terms of excellent breaking elongation retention rate and breaking strength retention rate after the heat resistance test. , 90-98% is more preferred.
Next, as the second polymerization step, the above-mentioned monomer (а) is added and polymerized to obtain a polymer block (A). The conversion rate of the monomer (а) in the second polymerization step is preferably 50 to 99%.
This makes it possible to obtain an ABA triblock copolymer composed of a polymer block (A) -polymer block (B) -polymer block (A). In this case, it is preferable to use a bifunctional polymerization initiator or a polymerization control agent as the polymerization initiator. According to this method, the process can be simplified as compared with the case where each block is sequentially polymerized and manufactured. Further, by repeating the above-mentioned first polymerization step and second polymerization step, a higher-order block copolymer such as a pentablock copolymer can be obtained.
The initial concentration of the acrylic monomer (b) when the polymer block (B) is obtained in the first polymerization step is excellent in breaking elongation retention rate and breaking strength retention rate after the heat resistance test, and oil resistance. In that respect, 2,500 mM or more is preferable, and 2,800 mM or more is more preferable.

In the present disclosure, the polymerization of the block copolymer may be carried out in the presence of a chain transfer agent, if necessary, regardless of the polymerization method.
Known chain transfer agents can be used, specifically, ethanethiol, 1-propanethiol, 2-propanethiol, 1-butanethiol, 2-butanethiol, 1-hexanethiol, 2-hexane. Thiol, 2-methylheptane-2-thiol, 2-butylbutane-1-thiol, 1,1-dimethyl-1-pentanethiol, 1-octanethiol, 2-octanethiol, 1-decanethiol, 3-decanethiol, 1-Undecanethiol, 1-dodecanethiol, 2-dodecanethiol, 1-tridecanethiol, 1-tetradecanethiol, 3-methyl-3-undecanethiol, 5-ethyl-5-decanethiol, tert-tetradecanethiol, 1 -In addition to alkylthiol compounds having an alkyl group having 2 to 20 carbon atoms such as hexadecanethiol, 1-heptadecanethiol and 1-octadecanethiol, mercaptoacetic acid, mercaptopropionic acid, 2-mercaptoethanol and the like can be mentioned. One or more of them can be used.

In the present disclosure, the block copolymer may be polymerized by a bulk polymerization or the like without using a polymerization solvent, regardless of the polymerization method, but a polymerization solvent may be used if necessary. ..
Examples of the polymerization solvent include nitrile solvents, aromatic solvents, ketone solvents, ester solvents, ortho ester solvents, dimethylformamide, dimethyl sulfoxide, alcohol and water.
Specific examples of the nitrile-based solvent include acetonitrile, isobutyronitrile, benzonitrile and the like.
Specific examples of the aromatic solvent include benzene, toluene, xylene, anisole and the like.
Specific examples of the ketone solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone and the like.
Specific examples of the ester solvent include methyl acetate, ethyl acetate, propyl acetate, butyl acetate and the like.
Specific examples of the ortho ester solvent include trimethyl orthoacetate, triethyl orthoate, triethyl orthoate (n-propyl), tri (isopropyl) orthoacetate, trimethyl orthoacetate, triethyl orthoacetate, triethyl orthopropionate, ortho n-. Examples thereof include trimethyl butyrate and trimethyl orthoisobutyrate.
Among the above, from the viewpoint of polymerization controllability, more specifically, from the viewpoint of having few side reactions such as chain transfer reaction, nitrile solvent, aromatic solvent, ketone solvent, ester solvent and orthoester solvent. It is preferable to use a solvent containing at least one selected from the group consisting of solvents, and among these, acetonitrile, anisole, acetone, methyl acetate, ethyl acetate and trimethyl orthoacetate are preferable.

The method for producing a block copolymer having the polymer block (A) and the polymer block (B) of the present disclosure preferably includes a step of removing volatile components such as a solvent. Examples of the step of removing the volatile matter include reprecipitation and purification, and a method of using a solvent removing device such as a twin-screw continuous kneader, a flow-down evaporator, and a thin-film evaporator.

As the reprecipitation purification, a known method of reprecipitating the polymer in a poor solvent can be adopted.

The temperature condition of the method using the solvent removing device is preferably 100 to 350 ° C., more preferably 120 to 300 ° C., particularly preferably 150 to 250 ° C., and the vacuum degree condition is preferably 10 to 300 Torr. 200 Torr is more preferable, and 10 to 150 Torr is particularly preferable.

In the method using a solvent removing device, it is preferable to add an antioxidant for the purpose of suppressing a decrease in the molecular weight of the block copolymer.
Examples of the antioxidant include a phenol-based antioxidant, a phosphorus-based antioxidant, a sulfur-based antioxidant, and the like.
Examples of the phenolic acid antioxidant include hindered phenols such as 2,6-di-t-butylhydroxytoluene. Commercially available products include ADEKA's ADEKA STAB AO-20, AO-30, AO-40, AO-50, AO-60, AO-70, AO-80, etc., and BASF's Irganox 1010. 1035, 1076, 1098 and the like can be mentioned.
Examples of the phosphorus-based antioxidant include phosphines such as trialkylphosphine and triarylphosphine, and trialkyl phosphite and triaryl phosphite. Commercially available products of these derivatives include ADEKA STAB PEP-4C, PEP-8, PEP-24G, PEP-36, HP-10, 260, 522A, 329K, 1178, 1500, 135A, 3010 and the like. , BASF, Inc., Irgafos 168 and the like.
Examples of the sulfur-based antioxidant include thioether-based compounds, and examples of commercially available products include ADEKA Stub AO-23, AO-412S, and AO-503A manufactured by ADEKA Corporation.
These may be used alone or in combination of two or more. Preferred combinations of these antioxidants include a combination of a phenol-based antioxidant and a phosphorus-based antioxidant, and a combination of a phenol-based antioxidant and a sulfur-based antioxidant.
The content ratio of the antioxidant may be appropriately set according to the purpose, and is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the block copolymer. be.
By setting the content to 0.1 parts by mass or more, the effect of suppressing the decrease in the molecular weight of the block copolymer can be enhanced, and by setting the content to 5 parts by mass or less, the coloring of the block copolymer can be suppressed. can.

Among the steps for removing volatile components, a method using a solvent removing device is preferable from the viewpoint of productivity, and a biaxial continuous kneader is further preferable.

5. Applications The polymers obtained by the manufacturing method of the present invention are various packings, gaskets, hose materials, adhesive raw materials, building / civil engineering materials, daily miscellaneous goods, etc. for automobile parts, electrical appliances, medical products, etc. Can be used in the field.

Further, according to the triblock copolymer composed of the polymer block (A) -polymer block (B) -polymer block (A) obtained by the production method of the present invention, extremely high heat resistance and oil resistance are obtained. It is possible to obtain an elastomer material that exhibits the above. Therefore, among these, for example, in automobile applications, it is suitably used as a sealing material, packing, tube, hose, engine cover, tank cap, etc., as a component in an engine room. As an electric material, it is also suitably used for heat-generating home appliances such as ovens, toasters, IH heaters, electric heaters, and hot air heaters.

Further, the elastomer composition containing the triblock copolymer can be molded and processed into a desired shape to form automobile parts, home appliances / OA equipment parts, medical equipment parts, packaging materials, civil engineering and construction materials, and electric wires. , Can be suitably used as a material in a wide range of fields such as miscellaneous goods.
Hereinafter, the elastomer composition will be described.

<Elastomer composition>
The triblock copolymer can be applied alone as an elastomer material, but may be an embodiment of a composition containing known additives and the like, if necessary. In particular, when the block copolymer contains a cross-linking functional group in at least one of the polymer block (A) and the polymer block (B), a cross-linking agent and a cross-linking accelerator capable of reacting with the functional group are blended. However, it is preferable in that an elastomer having a small value of permanent compression strain can be obtained by subjecting it to heat treatment or the like as necessary.

When the triblock copolymer contains a structural unit derived from a crosslinkable monomer having a carboxyl group, a polyvalent amine, a polyfunctional isocyanate or the like is preferably used as the crosslinking agent.
Specific examples of the polyvalent amine include aliphatic diamine compounds such as hexamethylenediamine, hexamethylenediamine carbamate, N, N'-dicinnamylidene-1,6-hexanediamine; and 4,4'-methylenebiscyclohexylamine carbamate. Alicyclic diamine compounds; 4,4'-methylene dianiline, m-phenylenediamine, 4,4'-diaminodiphenyl ether, 4,4'-(m-phenylenediisopropylidene) dianiline, 4,4'-(p) -Phenylenedisopropylidene) dianiline, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane, 4,4'-diaminobenzanilide, m-xylylene diamine, p-xylylene diamine, 1, Examples thereof include aromatic diamine compounds such as 3,5-benzenetriamine and 1,3,5-benzenetriaminomethyl.
Specific examples of the polyfunctional isocyanate include hexamethylene diisocyanate, dimethyldiphenylenediisocyanate, isophorone diisocyanate and the like.

When a polyvalent amine is used, guanidine compounds such as 1,3-di-o-tolylguanidine and 1,3-diphenylguanidine; imidazole compounds such as 2-methylimidazole and 2-phenylimidazole; phosphoric acid, carbonic acid and bicarbonate. , Salts of weak acids such as alkali metal salts (Li, Na, K) of acids such as stearic acid and lauric acid; triethylenediamine, 1,8-diazabicyclo- [5.4.0] undecene-7 and the like third. Secondary amines; Tertiary phosphin compounds such as triphenylphosphine and tri (methyl) phenylphosphine; cross-linking aids such as quaternary onium salts such as tetrabutylammonium bromide, tetrabutylammonium chloride, octadecyltri n-butylammonium bromide and the like. It is preferable to use in combination.

When the triblock copolymer contains a structural unit derived from a crosslinkable monomer having an epoxy group, the crosslinker includes an organocarboxylic acid ammonium salt, a dithiocarbamate salt, a polyvalent carboxylic acid or an anhydrate. A combination with a quaternary ammonium salt or a phosphonium salt is preferably used.
Specific examples of the ammonium benzoate salt include ammonium benzoate and the like.
Specific examples of the dithiocarbamate include zinc salts such as dimethyldithiocarbamic acid, diethyldithiocarbamic acid and dibenzyldithiocarbamic acid, iron salts, tellurium salts and the like.
Specific examples of the polyvalent carboxylic acid include malonic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, maleic acid, citric acid, tartrate acid, phthalic acid and the like.
Specific examples of the quaternary ammonium salt include tetraethylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium bromide, n-dodecyltrimethylammonium bromide, octadecyltrimethylammonium bromide and the like.
Specific examples of the phosphonium salt include triphenylbenzylphosphonium chloride, triphenylbenzylphosphonium bromide, triphenylbenzylphosphonium iodide, triethylbenzylphosphonium chloride, tetrabutylphosphonium bromide and the like.

When the triblock copolymer contains a structural unit derived from a crosslinkable monomer having a hydroxyl group, a polyfunctional isocyanate or the like is preferably used as the crosslinking agent.

When the triblock copolymer contains a structural unit derived from a crosslinkable monomer having a primary or secondary amino group, a polyfunctional isocyanate, a polyfunctional glycidyl compound and the like are preferably used as the crosslinking agent.

When the triblock copolymer contains a polymerizable unsaturated group, it is a dithiol compound such as 1,2-ethanedithiol, 1,4-butanethiol, 1,10-decanethiol, 1,4-benzenethiol, or a dithiol compound. En-thiol reactions with polyvalent thiols such as trithiol compounds such as ethane-1,1,1-trithiol and 1,3,5-benzenetrithiol can be utilized.

When the cross-linking group of the triblock copolymer is a reactive silicon group, it is not necessary to add a cross-linking agent or the like because a cross-linking reaction occurs due to moisture.

Other above-mentioned additives include, for example, fillers such as carbon black, processing aids such as stearic acid and higher fatty acid esters, and anti-aging of bis [4- (1-phenyl-1-methylethyl) phenyl] amine. Examples include agents, plasticizers, oils, antioxidants and UV absorbers. The blending amount of the additive is preferably 0% by mass or more and 10% by mass or less, more preferably 0% by mass or more and 5% by mass or less, and further preferably 0% by mass or more and 2 by mass with respect to the block copolymer. It is less than mass%.

A thermoplastic resin may be added for the purpose of adjusting the performance or processability of the elastomer composition containing the triblock copolymer. Specific examples of the thermoactive resin include polyolefin resins such as polyethylene and polypropylene, styrene resins of polystyrene, vinyl resins such as polyvinyl chloride, polyester resins, and polyamide resins. Further, other elastomers may be added and mixed.

The elastomer composition containing the triblock copolymer exhibits good fluidity when heated to about 150 ° C. or higher and 250 ° C. or lower. Therefore, it can be applied to molding processes by various methods such as extrusion molding, injection molding, and casting molding.

Hereinafter, the present invention will be specifically described based on Examples. The present invention is not limited to these examples. In the following, "parts" and "%" mean parts by mass and% by mass unless otherwise specified.
The methods for analyzing the polymers obtained in Production Examples, Examples and Comparative Examples are described below.

<Monomer conversion rate>
First, 0.1 g of the solution before the start of polymerization and the polymerization solution at a predetermined time were sampled and dissolved in 5.0 g of acetone to prepare a 2 wt% solution, and then isobutyl acrylate was added to the solution as an internal standard substance. 0.02 g was added to obtain a measurement sample.
Next, the monomer concentration X in the solution before the start of polymerization and the monomer concentration Y in the polymerization solution at a predetermined time were obtained by gas chromatography measurement of the measurement sample, and the calculation formula: (XY) /. The conversion rate (%) of the monomer was calculated according to X × 100.
○ Measurement conditions Measuring equipment: 7820A manufactured by Agilent Technologies
Column: CP-Sil 5CB (dimethylpolysiloxane) manufactured by GL Science Co., Ltd.
Column length 30m, column diameter 0.32mm, df = 0.3μm
Carrier gas: He
Gas flow rate: 1.5 mL / min
Split ratio: 40: 1
Injection volume: 1.0 μL
Injection port temperature: 230 ° C
Detector: FID
Detector temperature: 250 ° C
H ₂ flow rate: 40 mL / min
Air flow rate: 450 mL / min
N ₂ flow rate: 25 mL / min
Temperature rise conditions: 50 ° C (5 min) → 10 ° C / min → 230 ° C (5 min)

<Measurement of molecular weight of polymer>
The obtained polymer was subjected to gel permeation chromatography (GPC) measurement under the conditions described below to obtain a number average molecular weight (Mn) and a weight average molecular weight (Mw) in terms of polystyrene. Moreover, the molecular weight distribution (Mw / Mn) was calculated from the obtained values.
○ Measurement conditions Column: Tosoh TSKgel SuperMultipore HZ-M x 4 Solvent: Tetrahydrofuran Temperature: 40 ° C
Detector: RI
Flow velocity: 600 μL / min

<Polymer composition ratio>
The composition ratio of the obtained polymer was identified and calculated by ¹ H-NMR measurement.

<Glass transition temperature (Tg) of polymer>
The Tg of the obtained polymer was determined from the intersection of the baseline and the tangent at the inflection of the heat flux curve obtained using a differential scanning calorimeter. The heat flux curve shows that about 10 mg of the sample is cooled to -50 ° C, held for 5 minutes, then heated to 300 ° C at 10 ° C / min, subsequently cooled to -50 ° C, held for 5 minutes, and then 10 ° C /. It was obtained under the condition that the temperature was raised to 350 ° C. in min.
Measuring equipment: DSC6220 manufactured by SII Nanotechnology Co., Ltd.
Measurement atmosphere: Under nitrogen atmosphere By measuring the differential scanning calorimetry of the block copolymers obtained in Examples and Comparative Examples, the turning points corresponding to the polymer blocks (A) and the polymer blocks (B). Can be obtained, and the Tg of each polymer block can be obtained from these.

Next, the evaluation method of the elastomer in Examples and Comparative Examples will be described below.
<Initial tensile characteristics>
The pellet-shaped polymer was heat-press molded at 210 ° C. to prepare a sheet having a thickness of about 1 mm.
Using the sheet obtained above as a sample, the tensile strength at break and the elongation at break under normal conditions (25 ° C.) were measured according to JIS K6251.

<Heat resistance>
The same sheet as the initial tensile characteristics was used as the sample.
The sample punched into a dumbbell mold was put into an explosion-proof dryer at 150 ° C., and the sample was taken out after 1000 hours had passed. The heat resistance was evaluated by calculating the Mn retention rate with respect to the initial Mn measurement value from the GPC measurement. Further, in accordance with JIS K 6251, the tensile breaking strength and breaking elongation under normal conditions (25 ° C.) were measured, and the breaking elongation and breaking strength retention rate with respect to the initial measured values were calculated.

<Oil resistance>
The same sheet as the initial tensile characteristics was used as the sample.
The sample punched into a dumbbell shape was immersed in engine oil (Nissan genuine engine oil "Motor Oil Extra Save X 10W-30 SJ"), heated to 150 ° C., and the sample was taken out after 1000 hours had passed. Then, the taken-out sample was allowed to cool, and the swelling rate was evaluated from the weight change rate after lightly wiping. Further, for the same sample, the tensile breaking strength and breaking elongation under normal conditions (25 ° C.) were measured according to JIS K 6251, and the breaking elongation and breaking strength retention rate with respect to the initial measured values were calculated.

<Formability>
The formability was evaluated for each of the following items.
(1) Fluidity A pellet-shaped polymer was used as the sample.
The evaluation was made based on the heating temperature and load conditions when the melt flow rate (MFR) measured according to ASTM D 1239 was 0.1 g / 10 min or more. It was judged that the more the melt flow rate can be obtained under low temperature and low load conditions, the better the fluidity.
(2) Deterioration of resin The molecular weight of the sample before and after the above MFR measurement was measured, the rate of change was calculated, and the evaluation was made based on the following criteria.
◯: Change rate less than 10% ×: Change rate 10% or more (3) Appearance A molded product of 125 mm × 125 mm × thickness 2 mm was injection-molded under the following conditions, and the obtained molded product was visually observed based on the following criteria. The appearance was evaluated by.
◯: No wrinkles, irregularities or hangnail defects are observed on the surface ×: Injection molding machine with wrinkles, irregularities or hangnail defects on the surface: 100MSIII-10E (trade name, manufactured by Mitsubishi Heavy Industries, Ltd.)
Injection molding temperature: 240 ° C
Injection pressure: 30%
Injection time: 3 sec
Mold temperature: 40 ° C

≪Synthesis of RAFT agent≫
Synthesis example 1
(Synthesis of 1,4-bis (n-dodecylsulfanylthiocarbonylsulfanylmethyl) benzene)
Add 1-dodecanethiol (42.2 g), 20% aqueous KOH solution (63.8 g) and trioctylmethylammonium chloride (1.5 g) to a eggplant-shaped flask, cool in an ice bath, and carbon disulfide (15.9 g). ), Tetrahydrofuran (hereinafter also referred to as "THF") (38 ml) was added, and the mixture was stirred for 20 minutes. A THF solution (170 ml) of α, α'-dichloro-p-xylene (16.6 g) was added dropwise over 30 minutes. After reacting at room temperature for 1 hour, the mixture was extracted from chloroform, washed with pure water, dried over anhydrous sodium sulfate, and concentrated with a rotary evaporator. The obtained crude product is purified by column chromatography and then recrystallized from ethyl acetate to form 1,4-bis (n-dodecylsulfanylthiocarbonylsulfanylmethyl) benzene represented by the following formula (4). (Hereinafter also referred to as "DLBTTC") was obtained in a yield of 80%. ¹ The peak of the target product was confirmed at 7.2 ppm, 4.6 ppm and 3.4 ppm by 1 H-NMR measurement.

≪Manufacturing of block copolymer≫
Production Example 1 (Production of Polymer 1)
RAFT agent (DLBTTC) (3.01 g), 2,2'-azobis2-methylbutyronitrile (ABN-E) (0.18 g) obtained in Synthesis Example 1 in a 2 L flask equipped with a stirrer and a thermometer. , Ethyl acrylate (EA) (320.4 g) and acetonitrile (352.9 g) were charged, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 60 ° C. After 8 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rate of EA was 91%, and the molecular weight was Mn63,900, Mw74,100, Mw / Mn1.16 according to GPC (gel permeation chromatography) measurement (polystyrene conversion). EA (42.2 g), isobornyl acrylate (IBXA) (95.1 g) and acetonitrile (338.5 g) were added to the above polymerization solution, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 60 ° C. .. After 8 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rates of EA and IBXA were 92% and 95%, respectively.
Irganox 1010 (manufactured by BASF) (0.3 parts by mass with respect to 100 parts by mass of the block copolymer contained in the polymerization liquid) was added to the obtained polymerization solution to uniformly dissolve the block copolymer, and then a biaxial continuous kneader was used. (The solvent was removed using an S1KRC kneader (trade name, manufactured by Kurimoto Iron Works) under the conditions of a kneading temperature of 240 ° C., a vacuum degree of 80 Torr, and a liquid supply amount of 1 kg / h. After cooling with a pelletizer, the polymer 1 in the form of pellets was obtained. The molecular weights of the obtained polymer 1 were Mn89,800, Mw117,000, and Mw / Mn1.30. The results of measuring the conversion rate of the body and the molecular weight of the polymer are shown in Table 1.

Production Examples 2 to 13 and Comparative Production Examples 2 and 3 (Production of Polymers 2 to 13, 17 and 18)
The same operations as in Production Example 1 were carried out except that the raw materials, the amount used and the polymerization conditions were as described in Tables 1 and 2, to obtain polymers 2 to 13, 17, and 18. The results of measuring the conversion rate of the monomer and the molecular weight of the polymer are shown in Tables 1 and 2.

Production Example 14 (Production of Polymer 14)
2-{[(2-carboxyethyl) sulfanylthiocarbonyl] sulfanyl} propanoic acid (1.16 g), ABN-E (0.35 g), N-phenylmaleimide (PhMI) in a 2 L flask equipped with a stirrer and a thermometer. (41.6 g), styrene (St) (27.1 g) and acetonitrile (131.4 g) were charged, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 70 ° C. After 3 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rates of PhMI and St were 99% and 92%, respectively. The molecular weights were Mn12,500, Mw13,500, and Mw / Mn1.08 as measured by GPC (in terms of polystyrene). Subsequently, EA (320.4 g) and acetonitrile (166.6 g) were added to the above-mentioned polymerization solution, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 70 ° C. After 8 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rate of EA was 92%, and the molecular weight was Mn78,200, Mw100,000, and Mw / Mn1.28 according to GPC measurement (polystyrene conversion). Subsequently, PhMI (41.6 g), St (27.1 g) and acetonitrile (391.0 g) were charged into the above-mentioned polymerization solution, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 70 ° C. After 6 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rates of PhMI and St were 99% and 90%, respectively.
Irganox 1010 (manufactured by BASF) (0.3 parts by mass with respect to 100 parts by mass of the block copolymer contained in the polymerization liquid) was added to the obtained polymerization solution to uniformly dissolve the block copolymer, and then a biaxial continuous kneader was used. (The solvent was removed using an S1KRC kneader (trade name, manufactured by Kurimoto Iron Works) under the conditions of a kneading temperature of 240 ° C., a vacuum degree of 80 Torr, and a liquid supply amount of 1 kg / h. After cooling with a pelletizer, the polymer 14 in the form of pellets was obtained. The molecular weights of the obtained polymer 14 were Mn88,700, Mw116,000, and Mw / Mn1.31. The results of measuring the conversion rate of the body and the molecular weight of the polymer are shown in Table 2.

Production Example 15 (Production of Polymer 15)
2-Methyl-2- [N-tert-butyl-N- (1-diethylphosphono-2,2-dimethylpropyl) -N-oxyl] propionic acid (1.74 g) in a 2 L flask equipped with a stirrer and a thermometer. ), Hexanediol diacrylate (0.53 g) and ethanol (3.4 g) were charged, sufficiently degassed by nitrogen bubbling, and the reaction was started in a constant temperature bath at 75 ° C. After 1 hour, the solvent was cooled to room temperature and then distilled off under reduced pressure.
Subsequently, EA (320.4 g) and anisole (447.6 g) were charged into the residue after distillation under reduced pressure, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 105 ° C. After 10 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rate of EA was 92%, and the molecular weight was Mn66,100, Mw97,200, and Mw / Mn1.47 as measured by GPC (in terms of polystyrene). Subsequently, PhMI (83.1 g), St (54.2 g) and anisole (244.6 g) were charged into the above-mentioned polymerization solution, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 105 ° C. After 3 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rates of PhMI and St were 99% and 84%, respectively.
Irganox 1010 (manufactured by BASF) (0.3 parts by mass with respect to 100 parts by mass of the block copolymer contained in the polymerization liquid) was added to the obtained polymerization solution to uniformly dissolve the block copolymer, and then a biaxial continuous kneader was used. (The solvent was removed using an S1KRC kneader (trade name, manufactured by Kurimoto Iron Works) under the conditions of a kneading temperature of 240 ° C., a vacuum degree of 80 Torr, and a liquid supply amount of 1 kg / h. After cooling with a pelletizer, the polymer 15 in the form of pellets was obtained. The molecular weights of the obtained polymer 15 were Mn74,500, Mw115,000, and Mw / Mn1.54. The results of measuring the conversion rate of the body and the molecular weight of the polymer are shown in Table 2.

Comparative Production Example 1 (Production of Polymer 16)
Copper (I) bromide (0.66 g), pentamethyldiethylenetriamine (2.38 g), EA (320.4 g) and anisole (446.0 g) were charged in a 2 L flask equipped with a stirrer and a thermometer, and nitrogen bubbling was performed. I degassed enough. After adding ethylene bis (2-bromoisobutyrate) (0.89 g), polymerization was started in a constant temperature bath at 70 ° C. After 8 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rate of EA was 92%, and the molecular weights were Mn63,500, Mw71,800, and Mw / Mn1.13 according to GPC measurement (polystyrene conversion). Subsequently, EA (42.2 g), IBXA (95.1 g) and anisole (336.5 g) were charged in the above polymerization solution, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 70 ° C. After 8 hours, the reaction was stopped by cooling to room temperature. At this point, the conversion rates of EA and IBXA were 90% and 91%, respectively.
Irganox 1010 (manufactured by BASF) (0.3 parts by mass with respect to 100 parts by mass of the block copolymer contained in the polymerization liquid) was added to the obtained polymerization solution to uniformly dissolve the block copolymer, and then a biaxial continuous kneader was used. (The solvent was removed using an S1KRC kneader (trade name, manufactured by Kurimoto Iron Works) under the conditions of a kneading temperature of 240 ° C., a vacuum degree of 80 Torr, and a liquid supply amount of 1 kg / h. After cooling with a pelletizer, the polymer 16 was obtained in the form of pellets. The molecular weights of the obtained polymer 16 were Mn88,200, Mw113,000, and Mw / Mn1.28. The results of measuring the conversion rate of the body and the molecular weight of the polymer are shown in Table 2.

The abbreviations in Tables 1 and 2 mean the following compounds.
-PhMI: N-phenylmaleimide-St: styrene-EA: ethyl acrylate-IBXA: isobornyl acrylate-CBSTSP: 2-{[(2-carboxyethyl) sulfanylthiocarbonyl] sulfanyl} propanoic acid (Wako Pure Chemical Industries, Ltd.) RAFT agent)
ABN-E: 2,2'-azobis (2-methylbutyronitrile)
-HDDA: 1,6-hexanediol diacrylate-SG1-MAA: 2-methyl-2- [N-tert-butyl-N- (1-diethylphosphono-2,2-dimethylpropyl) -N-oxyl] Propionic acid (nitroxide compound manufactured by Arkema)
EBBIB: Ethylene bis (2-bromoisobutyrate)
CuBr: Copper bromide (I)
PMDETA: Pentamethyldiethylenetriamine

Examples 1 and 2 and Comparative Example 1
For block copolymers 1, 2 and 16, the composition ratio of the polymer block (A) calculated from ¹ H-NMR, the composition ratio of the polymer block (B), Tg obtained by DSC measurement, the molecular weight of the polymer, and the initial tension. Physical properties and heat resistance (Mn retention rate) were evaluated. The results are shown in Table 3.

Examples 3 to 15 and Comparative Examples 2 and 3
For block copolymers 3 to 15, 17 and 18, the composition ratio of the polymer block (A) calculated from ¹ H-NMR, the composition ratio of the polymer block (B), the Tg obtained from the DSC measurement, the molecular weight of the polymer, The initial tensile characteristics, heat resistance (Mn retention rate), tensile properties after the heat resistance and oil resistance test, swelling rate after the oil resistance test, and moldability were evaluated. The results are shown in Table 4.

As is clear from the results of Examples 1 to 15, the block copolymer obtained by the production method of the present invention exhibited high heat resistance (Mn retention rate). Further, when the Tg of the polymer block (A) is 150 ° C. or higher (Examples 3 to 15), the fracture elongation retention rate and the fracture strength retention rate after the heat resistance test, the oil resistance, and the moldability are also excellent. rice field.
Here, in a comparison in which the initial concentration of the acrylic monomer (b) is constant, the conversion rate of the acrylic monomer (b) when obtaining the polymer block (B) is 90% or more (Example). In 5 and 6), the breaking elongation retention rate and the breaking strength retention rate after the heat resistance test were further superior to those in the case where the conversion was less than 90% (Examples 3 and 4).
Further, when the initial concentration of the acrylic monomer (b) for obtaining the polymer block (B) is 2,500 mM or more, the initial concentration is less than 2,500 mM (Example 13). After the heat resistance test, the breaking elongation retention rate, the breaking strength retention rate, and the oil resistance were further excellent.
On the other hand, as is clear from the results of Comparative Example 1, the block copolymer containing copper obtained by the ATRP method had significantly poor heat resistance (Mn retention rate). Further, as is clear from the results of Comparative Examples 2 and 3, when the conversion rate of the acrylic monomer (b) was less than 83% or more than 98%, the monomer (а) was added and polymerized. In some cases, the breaking elongation retention rate and breaking strength retention rate after the heat resistance test, as well as the oil resistance were significantly poor.

The block copolymer obtained by the production method of the present invention exhibits good rubber elasticity and is also excellent in moldability. Therefore, it can be widely applied in the fields of packings, gaskets, hose materials, etc. for automobile parts, electrical appliances, medical products, etc., adhesive raw materials, construction / civil engineering members, daily miscellaneous goods, and the like.
Further, according to the block copolymer obtained by the production method of the present invention, it is possible to obtain an elastomer material exhibiting extremely high heat resistance and oil resistance. Therefore, among these, for example, in automobile applications, it is suitably used as a sealing material, packing, tube, hose, engine cover, tank cap, etc., as a component in an engine room. As an electric material, it is also suitably used for heat-generating home appliances such as ovens, toasters, IH heaters, electric heaters, and hot air heaters.
The elastomer composition containing the block copolymer of the present disclosure can be molded and processed into a desired shape to form automobile parts, home appliances / OA equipment parts, medical equipment parts, packaging materials, civil engineering and construction materials, electric wires, and the like. It can be suitably used as a material in a wide range of fields such as miscellaneous goods.

Claims (10)

It is a method for producing a block copolymer by a living radical polymerization method (excluding the TERP method) having an exchange chain mechanism.
The block copolymer has a polymer block (A) having a glass transition temperature (Tg) of 25 ° C. or higher and an acrylic polymer block (B) having a Tg of less than 25 ° C.
A step of polymerizing the acrylic monomer (b) constituting the acrylic polymer block (B) to a conversion rate of 90 to 98% to obtain the acrylic polymer block (B).
Next, a method for producing a block copolymer, which comprises a step of adding a monomer (а) constituting the polymer block (A) and polymerizing the polymer block (A) to obtain the polymer block (A). It is a method for producing a block copolymer by the nitroxy radical method (NMP method).
The block copolymer has a polymer block (A) having a glass transition temperature (Tg) of 25 ° C. or higher and an acrylic polymer block (B) having a Tg of less than 25 ° C.
A step of polymerizing the acrylic monomer (b) constituting the acrylic polymer block (B) to a conversion rate of 83 to 98% to obtain the acrylic polymer block (B).
Next, a method for producing a block copolymer, which comprises a step of adding a monomer (а) constituting the polymer block (A) and polymerizing the polymer block (A) to obtain the polymer block (A). The method for producing a block copolymer according to claim 1 or 2, wherein the Tg of the polymer block (A) is 150 ° C. or higher. Claims 1 to 1, wherein as the polymerization solvent, a solvent containing at least one selected from the group consisting of a nitrile solvent, an aromatic solvent, a ketone solvent, an ester solvent and an orthoester solvent is used. The method for producing a block copolymer according to any one of claims 3. The invention according to any one of claims 1 to 4, wherein the initial concentration of the acrylic monomer (b) when obtaining the acrylic polymer block (B) is 2,500 mM or more. A method for producing a block copolymer of. As the first polymerization step, the acrylic monomer (b) is polymerized to a conversion rate of 90 to 98% using a polyfunctional polymerization control agent to obtain the acrylic polymer block (B). When,
Next, as the second polymerization step, the step of adding the monomer (а) and polymerizing to obtain the polymer block (A) is included.
The method for producing a block copolymer according to any one of claims 1 to 5. As the first polymerization step, a step of polymerizing the monomer (а) to obtain the polymer block (A), and a step of obtaining the polymer block (A).
Next, as a second polymerization step, the acrylic monomer (b) is added and polymerized to a conversion rate of 90 to 98% to obtain the acrylic polymer block (B).
Further, as a third polymerization step, the step of adding the monomer (а) and polymerizing to obtain the polymer block (A) is included.
The method for producing a block copolymer according to any one of claims 1 to 5. Any one of claims 1 to 7, wherein the block copolymer has a polymer block (A) containing structural units derived from styrenes and maleimide compounds, and an acrylic polymer block (B). The method for producing a block copolymer according to the section. The method for producing a block copolymer according to any one of claims 1 to 8, wherein the block copolymer is applied as an elastomer material. The method for producing a block copolymer according to any one of claims 1 to 8, wherein the block copolymer is applied as an elastomer material for automobiles.