JP2018172591A - Block copolymer, block copolymer composition and thin film using them - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a block copolymer that is excellent in microphase separation by self-organization and consequently can give a thin film having an extremely fine microdomain.SOLUTION: The block copolymer comprises (α) a (meth)acrylic acid ester block containing a (meth)acrylic acid ester monomer unit as a main structural unit and (β) an aromatic vinyl block containing an aromatic vinyl monomer unit as a main structural unit. The (meth)acrylic acid ester block (α) contains a (meth)acrylic acid ester monomer unit having a cationic group in a ratio of 0.5 to 4.5 mol% in the total repeating units constituting the (meth)acrylic acid ester block (α). The cationic group or a cationic group-containing group is a group in which atoms of Group 15 or Group 16 in the Periodic Table form an onium cation structure.SELECTED DRAWING: None

Description

  The present invention provides a block copolymer that is excellent in microphase separation by self-organization, and can thereby provide a thin film having extremely fine and good microdomains, and a block containing such a block copolymer The present invention relates to a copolymer composition and a thin film obtained using these.

  It is known that polymers composed of different monomer units are generally incompatible with each other, and when they are mixed, they are phase-separated into domains composed of the respective polymers. In addition, the greater the molecular weight of the polymer to be mixed and the greater the difference in polarity (for example, χ parameter difference) between the monomer units constituting each polymer, the stronger the incompatibility between the polymers. It is known that separation tends to occur. Such phase separation between polymers is called macrophase separation, and its scale (domain size) is usually 1 μm or more, typically several μm to several tens of μm.

  On the other hand, in addition to the macrophase separation described above, microphase separation with a phase separation scale on the nanometer order (several nm to several hundred nm) is also known for polymer phase separation. As an example, phase separation based on incompatibility between segment blocks in a block copolymer is known. For such a block copolymer, by causing microphase separation, various functions can be given based on the difference in physical properties between the fine regions formed by the microphase separation. Application to the field is expected. In particular, in the microphase separation of a block copolymer, a columnar (cylinder) structure, a lamellar structure, a co-continuous (gyroid) structure, or a spherical (depending on the change in the volume fraction of each segment block constituting the block copolymer. It is known that various phase separation structures such as (sphere) structures are formed, and if the structure and size of the formed microphase separation structure can be controlled, the degree of freedom in selecting the above functions is greatly improved. It is expected to be able to be made.

  Therefore, development of a polymer material having excellent microphase separation properties has been studied. For example, Patent Document 1 discloses a block copolymer containing styrene and methyl methacrylate (MMA), and it is reported that microphase separation occurs due to incompatibility of each segment block. ing. However, in the block copolymer of styrene and methyl methacrylate, in order to form a microphase separation structure, it is necessary to make the segment length (molecular weight) of each segment block relatively large. There was a limit to miniaturization. In other words, if the segment length (molecular weight) of each segment block is made too small, it is compatible without microphase separation, and the phase separation structure cannot be miniaturized. Therefore, there is a problem that an extremely fine pattern cannot be formed. there were.

JP, 2006-117865, A

  The present invention has been made in view of such circumstances, and is a block copolymer that is excellent in microphase separation by self-organization, and can thereby provide a thin film having extremely fine and good microdomains. It is an object of the present invention to provide a block copolymer composition containing such a block copolymer. Another object of the present invention is to provide a thin film obtained using these.

  As a result of intensive studies to achieve the above object, the present inventors have found that a block copolymer comprising a (meth) acrylic acid ester block (α) and an aromatic vinyl block (β) has (meth) acrylic. It has been found that the above object can be achieved by including a (meth) acrylic acid ester monomer unit having a specific amount of a cationic group in the acid ester block (α), and the present invention has been completed.

  That is, according to the present invention, a (meth) acrylate block (α) containing a (meth) acrylate monomer unit as a main structural unit, and an aromatic vinyl monomer unit as a main structural unit A block copolymer comprising an aromatic vinyl block (β), wherein the (meth) acrylate block (α) has a cationic group-containing (meth) acrylate monomer unit, A block copolymer containing 0.5 to 4.5 mol% in all repeating units constituting the (meth) acrylic acid ester block (α) is provided.

（上記一般式（１）中、Ｒ^１は水素原子またはメチル基を表し、Ａ^＋はカチオン性基またはカチオン性基含有基を表し、Ｘ⁻は任意の対アニオンを表し、ｍは０〜１０の整数である。）
本発明のブロック共重合体において、前記カチオン性基またはカチオン性基含有基は、周期表第１５族または第１６族の原子がオニウムカチオン構造を形成した基であることが好ましい。
本発明のブロック共重合体は、絶対分子量が１５，０００〜５０，０００であることが好ましい。
本発明のブロック共重合体は、分子量分布が１．０〜２．０であることが好ましい。 In the block copolymer of the present invention, the (meth) acrylic acid ester monomer unit having a cationic group is preferably a monomer unit represented by the following general formula (1).

(In the general formula (1), R ¹ represents a hydrogen atom or a methyl group, A ⁺ represents a cationic group or a cationic group-containing group, X ⁻ represents an arbitrary counter anion, and m represents 0-10. Is an integer.)
In the block copolymer of the present invention, the cationic group or the cationic group-containing group is preferably a group in which an atom of Group 15 or Group 16 of the periodic table forms an onium cation structure.
The block copolymer of the present invention preferably has an absolute molecular weight of 15,000 to 50,000.
The block copolymer of the present invention preferably has a molecular weight distribution of 1.0 to 2.0.

Moreover, according to this invention, the block copolymer composition containing said block copolymer and compounds other than this block copolymer is provided.
Furthermore, according to this invention, the thin film formed by microphase-separating said block copolymer or said block copolymer composition is provided.

  According to the present invention, a block copolymer capable of providing a thin film having ultrafine and good microdomains, and a block copolymer composition excellent in microphase separation by self-organization, and It is possible to provide a thin film that is obtained by using these and has extremely fine and good microdomains.

<Block copolymer>
The block copolymer of the present invention comprises a (meth) acrylate block (α) containing a (meth) acrylate monomer unit as a main structural unit, and an aromatic vinyl monomer unit as a main structural unit. An aromatic vinyl block (β) containing,
The (meth) acrylic acid ester block (α) contains a cationic group-containing (meth) acrylic acid ester monomer unit in all repeating units constituting the (meth) acrylic acid ester block (α). It is a block copolymer contained in a proportion of 5 to 4.5 mol%.
In the present invention, “(meth) acrylic acid” means “acrylic acid and / or methacrylic acid”.

  The (meth) acrylic acid ester block (α) contains a (meth) acrylic acid ester monomer unit as a main structural unit in the main chain structure and has a cationic group. The monomer unit is contained in a proportion of 0.5 to 4.5 mol% in all repeating units constituting the (meth) acrylic acid ester block (α).

  In the present invention, in a block copolymer comprising a (meth) acrylic acid ester block (α) and an aromatic vinyl block (β), a cationic group is contained in the (meth) acrylic acid ester block (α). The (meth) acrylic acid ester monomer unit to be contained in the above proportion, thereby appropriately increasing the incompatibility of the (meth) acrylic acid ester block with respect to the aromatic vinyl block (β). As a result, it is possible to improve the microphase separation, and as a result, it is possible to form extremely fine and good microdomains.

  The content ratio of the (meth) acrylic acid ester monomer unit having a cationic group is 0.5 to 4.5 mol% in all repeating units constituting the (meth) acrylic acid ester block (α), More preferably, it is 1.0-4.0 mol%, More preferably, it is 1.0-3.5 mol%. Even if the content ratio of the (meth) acrylic acid ester monomer unit having a cationic group is too small or too large, the effect of introducing the (meth) acrylic acid ester monomer unit having a cationic group, In other words, the effect of improving the incompatibility of the (meth) acrylic acid ester block with respect to the aromatic vinyl block (β) cannot be appropriately obtained, the microphase separation property is low, and the microdomain structure is excellent. It becomes difficult to form.

  The (meth) acrylic acid ester monomer unit having a cationic group may be a unit derived from a (meth) acrylic acid ester monomer having a cationic group. Although it does not specifically limit as a cationic group, From the viewpoint that the improvement effect of a micro phase-separation property can be heightened more, it is a cationic group in which the atom of group 15 or 16 of the periodic table formed the onium cation structure. It is preferable that the nitrogen atom is a cationic group in which an onium cation structure is formed.

  Specific examples of the cationic group include ammonium group, methylammonium group, butylammonium group, cyclohexylammonium group, anilinium group, benzylammonium group, ethanolammonium group, dimethylammonium group, diethylammonium group, dibutylammonium group, and nonylphenylammonium. Group, trimethylammonium group, triethylammonium group, n-butyldimethylammonium group, n-octyldimethylammonium group, n-stearyldimethylammonium group, tributylammonium group, trivinylammonium group, triethanolammonium group, N, N-dimethyl Ammonium groups such as ethanolammonium group and tri (2-ethoxyethyl) ammonium group; piperidinium group, 1-pyrrolidinium Group, 1-methylpyrrolidinium group, imidazolium group, 1-methylimidazolium group, 1-ethylimidazolium group, benzimidazolium group, pyrrolium group, 1-methylpyrrolium group, oxazolium group, benzoxazolium group Group, benzisoxazolium group, pyrazolium group, isoxazolium group, pyridinium group, 2,6-dimethylpyridinium group, pyrazinium group, pyrimidinium group, pyridazinium group, triazinium group, N, N-dimethylanilinium group, A group comprising a heterocyclic ring containing a cationic nitrogen atom such as quinolinium group, isoquinolinium group, indolinium group, isoindolinium group, quinoxalium group, isoquinoxalium group, thiazolium group; triphenylphosphonium salt, tributyl Phosphonium group, etc. Groups comprising a cationic phosphorus atom; but like, but is not limited thereto. Among these, from the viewpoint that the effect of improving the microphase separation can be further increased, an ammonium group is preferable, a methylammonium group, a butylammonium group, a cyclohexylammonium group, a dimethylammonium group, a diethylammonium group, a dibutylammonium group, Alkyl ammonium groups such as trimethylammonium group, triethylammonium group, n-butyldimethylammonium group, n-octyldimethylammonium group, n-stearyldimethylammonium group, tributylammonium group are more preferable, trialkylammonium group is more preferable, An ammonium group is particularly preferred. In addition, the (meth) acrylic acid ester block (α) constituting the block copolymer of the present invention may contain all the same as the cationic group, or may contain two or more different groups. The aspect which contains may be sufficient.

  The cationic group usually has a counter anion, but the counter anion is not particularly limited. For example, halide ions such as fluoride ion, chloride ion, bromide ion, iodide ion; Sulfate ion; Sulphite ion; Hydroxide ion; Carbonate ion; Hydrogen carbonate ion; Nitrate ion; Acetic acid ion; Perchlorate ion; Phosphate ion; Alkyloxy ion; Trifluoromethanesulfonate ion; Hexafluorophosphate ion; tetrafluoroborate ion; and the like. These counter anions may be appropriately selected according to the properties of the block copolymer to be obtained. The counter anions contained in the (meth) acrylate block (α) constituting the block copolymer of the present invention may all be the same or contain two or more different anions. It may be a mode.

Although it does not specifically limit as a (meth) acrylic acid ester monomer unit which has a cationic group, It is preferable that it is a unit represented by following General formula (1). In the case where the (meth) acrylate block (α) contains a unit represented by the following general formula (1) as a (meth) acrylate monomer unit having a cationic group, All the units represented by the following general formula (1) contained in the (meth) acrylate block (α) may be the same unit or two or more different units.

In the general formula (1), R ¹ represents a hydrogen atom or a methyl group, and is preferably a methyl group. A ⁺ represents a cationic group or a cationic group-containing group, and X ⁻ represents an arbitrary counter anion. m is an integer of 0 to 10, preferably an integer of 1 to 9, and more preferably an integer of 1 to 8.

In the general formula (1), A ⁺ represents a cationic group or a cationic group-containing group, and specific examples of the cationic group include those described above. As the cationic group-containing group, The group containing the cationic group mentioned above is mentioned.

In the general formula (1), X ⁻ represents an arbitrary counter anion. For example, specific examples of the counter anion include those described above.

  (Meth) acrylic ester for forming (meth) acrylic acid ester monomer units other than (meth) acrylic acid ester monomer units having a cationic group constituting (meth) acrylic acid ester block (α) Although it does not specifically limit as an acid ester monomer, For example, a (meth) acrylic-acid alkylester monomer and a (meth) acrylic-acid alkoxyalkylester monomer are mentioned.

Although it does not specifically limit as a (meth) acrylic-acid alkylester monomer, (meth) acrylic-acid methyl, (meth) acrylic-acid ethyl, (meth) acrylic-acid n-propyl, (meth) acrylic-acid isopropyl, (meta) C 1-8 linear or branched (meta) alkyl groups such as n-butyl acrylate, isobutyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, etc. ) Acrylic acid alkyl ester monomer; (meth) acrylic acid cycloalkyl ester monomer having 4 to 8 carbon atoms in the cycloalkyl group such as (meth) acrylic acid cyclohexyl; and the like.
Although it does not specifically limit as a (meth) acrylic-acid alkoxyalkylester monomer, (meth) acrylic-acid methoxymethyl, (meth) acrylic-acid ethoxymethyl, (meth) acrylic-acid 2-methoxyethyl, (meth) acrylic acid Alkoxyalkyl groups such as 2-ethoxyethyl, 2-propoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, and 4-methoxybutyl (meth) acrylate (Meth) acrylic acid alkoxyalkyl ester monomers having 2 to 8 carbon atoms;
Among these, (meth) acrylic acid alkyl ester monomers are preferable, linear or branched (meth) acrylic acid alkyl ester monomers having 1 to 8 carbon atoms in the alkyl group are more preferable, and (meth) More preferred is methyl acrylate, and particularly preferred is methyl methacrylate.

  The content ratio of (meth) acrylate monomer units (including (meth) acrylate monomer units having a cationic group) in the (meth) acrylate block (α) is microphase separation. From the viewpoint that it is more excellent in properties, it is preferably 70 to 100 mol%, more preferably 80 to 100 mol%, and particularly preferably in all repeating units constituting the (meth) acrylate block (α). 95 to 100 mol%. That is, the (meth) acrylic acid ester block (α) may contain a monomer unit copolymerizable with the (meth) acrylic acid ester monomer. ) It is particularly preferable that it is composed of an acrylate monomer unit (including a (meth) acrylate monomer unit having a cationic group).

The monomer copolymerizable with the (meth) acrylic acid ester monomer is not particularly limited, but is α, β-unsaturated nitrile such as acrylonitrile and methacrylonitrile; acrylic acid, methacrylic acid, maleic anhydride, etc. Unsaturated carboxylic acids or acid anhydrides of: 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-3-ethyl-1,3-butadiene, Conjugated dienes such as 2-methyl-1,3-pentadiene, 1,3-hexadiene, 1,3-cyclohexadiene; 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, dicyclopentadiene, 5 -Non-conjugated dienes such as ethylidene-2-norbornene;
In addition, aromatic vinyl monomers such as styrene constituting the aromatic vinyl block (β) described later are also included in less than 30 mol% in all repeating units constituting the (meth) acrylate block (α). be able to.

  The aromatic vinyl block (β) is a block containing an aromatic vinyl monomer unit as a main structural unit in the main chain structure.

  The aromatic vinyl monomer forming the aromatic vinyl monomer unit is not particularly limited, and examples thereof include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2- Ethyl styrene, 3-ethyl styrene, 4-ethyl styrene, 2,4-diisopropyl styrene, 2,4-dimethyl styrene, 4-t-butyl styrene, 5-t-butyl-2-methyl styrene, vinyl naphthalene, dimethylamino Examples thereof include methyl styrene and dimethylaminoethyl styrene. Among these, styrene, α-methylstyrene, or 4-methylstyrene is preferable, and styrene is particularly preferable. Note that. These aromatic vinyl monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  From the viewpoint that the content ratio of the aromatic vinyl monomer unit in the aromatic vinyl block (β) is superior to the microphase separation property, it is preferably in all the repeating units constituting the aromatic vinyl block (β). It is 70-100 mol%, More preferably, it is 80-100 mol%, Most preferably, it is 95-100 mol%. That is, the aromatic vinyl block (β) may contain a monomer unit that can be copolymerized with the aromatic vinyl monomer. It is particularly preferable that

Although it does not specifically limit as a monomer copolymerizable with an aromatic vinyl monomer, The thing similar to the monomer copolymerizable with the (meth) acrylic acid ester monomer mentioned above etc. are mentioned.
Moreover, the (meth) acrylic acid ester monomer and the (meth) acrylic acid ester monomer which have a cationic group which comprise the (meth) acrylic acid ester block ((alpha)) mentioned above are also aromatic vinyl blocks ((beta)). ) May be included in less than 30 mol%.

  The content ratio of the (meth) acrylic acid ester block (α) and the aromatic vinyl block (β) in the block copolymer of the present invention is “the unit constituting the (meth) acrylic acid ester block (α)”. The molar ratio of the number of moles of the monomer units: the number of moles of the monomer units constituting the aromatic vinyl block (β), preferably 0.3: 0.7 to 0.7 to 0.3, more preferably Is 0.35: 0.65-0.65: 0.35, more preferably 0.4: 0.6-0.6: 0.4. By making the content ratio of the (meth) acrylate block (α) and the aromatic vinyl block (β) in the above range, the microdomain structure formed by the microphase separation can be appropriately controlled, Thereby, the thin film obtained by causing microphase separation can be applied to a wide range of uses. For example, by setting the content ratio of the (meth) acrylic ester block (α) and the aromatic vinyl block (β) within the above range, the microdomain structure obtained by microphase separation is a lamellar structure. Thus, it can be suitably applied to fields where lamellar pattern formation is required, such as for photoresist applications.

  In addition, the block copolymer of the present invention may be one containing at least one (meth) acrylic acid ester block (α) and at least one aromatic vinyl block (β). When the acid ester block (α) is simply expressed as “A” and the aromatic vinyl block (β) is simply expressed as “B”, one (meth) acrylic acid ester block (α) and one aromatic An AB type diblock copolymer, an ABA type triblock copolymer, a BAB type triblock copolymer, and an AB type consisting of a vinyl block (β) An AB type tetrablock copolymer can be mentioned, and an AB type diblock copolymer is preferable from the viewpoint that a very fine and good microdomain can be formed more appropriately.

  Further, the block copolymer of the present invention may be one in which a (meth) acrylic acid ester block (α) and an aromatic vinyl block (β) are directly bonded, or any bonding group or ( It may be bonded via a polymer block other than the (meth) acrylate block (α) and the aromatic vinyl block (β), but the (meth) acrylate block (α) and aromatic It is preferable that the vinyl block (β) is directly bonded. Furthermore, the block copolymer of the present invention has an optional substituent or functional group at the polymer chain end, or a polymer block other than the (meth) acrylate block (α) and the aromatic vinyl block (β). May be combined.

  The block copolymer of the present invention has an absolute molecular weight (Mabs) of preferably 15,000 to 50,000, more preferably 20, from the viewpoint that ultrafine and good microdomains can be formed better. 000 to 40,000, more preferably 20,000 to 35,000. The block copolymer of the present invention contains a (meth) acrylic acid ester monomer unit having a cationic group in the (meth) acrylic acid ester block (α) at the above-described specific ratio, As a result, the incompatibility of the (meth) acrylic acid ester block (α) with respect to the aromatic vinyl block (β) is appropriately increased, so the absolute molecular weight (Mabs) is compared as described above. Even when the size is small, a microdomain structure can be formed satisfactorily. Further, by setting the absolute molecular weight (Mabs) within the above range, the obtained microdomain structure can be made finer.

  The method for measuring the absolute molecular weight (Mabs) of the block copolymer of the present invention is not particularly limited. For example, gel permeation chromatography (GPC) equipped with a light scatterometer such as a multi-angle light scattering detector and a viscometer. Can be measured. Alternatively, the block copolymer of the present invention first obtains an aromatic vinyl block (β), and then forms a (meth) acrylate block (α) continuously with the aromatic vinyl block (β). In the case of a product obtained by this method, the absolute molecular weight (Mabs) can also be measured by the following method. That is, first, for the aromatic vinyl block (β), the number average molecular weight (Mn) in terms of polystyrene was determined by gel permeation chromatography (GPC) equipped with a differential refractometer, and then, “( The molar ratio of “the number of moles of monomer units constituting the (meth) acrylate block (α): the number of moles of monomer units constituting the aromatic vinyl block (β)” is calculated, and such mole ratio The absolute molecular weight (Mabs) of the block copolymer can also be measured from the number average molecular weight (Mn) in terms of polystyrene of the aromatic vinyl block (β).

  Moreover, the molecular weight distribution of the block copolymer of the present invention is preferably 1.0 to 2.0, more preferably 1 from the viewpoint that the homogeneity of the formed microdomain structure can be further increased. It is 0.0-1.8, More preferably, it is 1.0-1.6. The method for measuring the molecular weight distribution is not particularly limited. For example, for a block copolymer, the number average molecular weight (Mn) in terms of polystyrene and the weight average molecular weight (Mw) by gel permeation chromatography (GPC) equipped with a differential refractometer. ), The ratio (Mw / Mn) is calculated, and the calculated ratio (Mw / Mn) can be used as the molecular weight distribution of the block copolymer.

  Although it does not specifically limit as a manufacturing method of the block copolymer of this invention, The monomer which comprises a (meth) acrylic acid ester block ((alpha)) using a polymerization initiator, and an aromatic vinyl block ((beta)) A method of polymerizing the monomers constituting the is preferable. For example, in the case of obtaining an AB type diblock copolymer, method (i): a monomer containing an aromatic vinyl monomer is polymerized to obtain an aromatic vinyl block (β), The obtained aromatic vinyl block (β) and a monomer containing a (meth) acrylic acid ester monomer including a (meth) acrylic acid ester monomer having a cationic group were mixed and polymerized. A method in which the reaction is continued and the (meth) acrylic acid ester block (α) is continuously formed with the aromatic vinyl block (β); or method (ii): a (meth) acrylic acid ester having a cationic group A monomer containing a (meth) acrylic acid ester monomer containing a monomer is polymerized to obtain a (meth) acrylic acid ester block (α), and the obtained (meth) acrylic acid ester block (α) And aromatic vinyl A method in which a monomer-containing monomer is mixed, the polymerization reaction is continued, and the aromatic vinyl block (β) is continuously formed with the (meth) acrylate block (α); It is done. In the method (i), the monomer containing the aromatic vinyl monomer that has not been reacted when the aromatic vinyl block (β) is obtained is obtained by converting the (meth) acrylic acid ester block (α). When it is obtained, it may be copolymerized with a (meth) acrylic acid ester monomer containing a (meth) acrylic acid ester monomer having a cationic group as long as the effects of the present invention are obtained. Moreover, in the method (ii), the (meth) acrylic acid ester containing the (meth) acrylic acid ester monomer which has the unreacted cationic group when the (meth) acrylic acid ester block ((alpha)) was obtained. When obtaining the aromatic vinyl block (β), the monomer may be copolymerized with a monomer containing an aromatic vinyl monomer as long as the effects of the present invention are obtained.

  As the polymerization method, any method such as ionic polymerization, radical polymerization, and living radical polymerization can be used, but living radical polymerization is preferable from the viewpoint that the polymerization reaction can be appropriately controlled.

Although it does not specifically limit as a polymerization initiator, When performing a polymerization reaction by living radical polymerization, the following (A)-(D) can be used, for example.
(A) Organic tellurium compound represented by the following general formula (2) (B) Mixture of an organic tellurium compound represented by the following general formula (2) and an azo polymerization initiator (C) The following general formula (2 A mixture of an organic tellurium compound represented by the following general formula (3) (D) an organic tellurium compound represented by the following general formula (2), an azo polymerization initiator, And a mixture with an organic ditellurium compound represented by the following general formula (3)

（上記一般式（２）中、Ｒ^２は、炭素数１〜８のアルキル基、アリール基または芳香族ヘテロ環基を表し、Ｒ^３およびＲ^４は、それぞれ独立して、水素原子または炭素数１〜８のアルキル基を表し、Ｒ^５は、炭素数１〜８のアルキル基、アリール基、芳香族ヘテロ環基、アシル基、アミド基、オキシカルボニル基またはシアノ基を表す。）

(In the above general formula (2), R ² represents an alkyl group having 1 to 8 carbon atoms, an aryl group or an aromatic heterocyclic group, and R ³ and R ⁴ each independently represent a hydrogen atom or a carbon number. It represents 1-8 alkyl group, R ⁵ represents an alkyl group having 1 to 8 carbon atoms, an aryl group, an aromatic heterocyclic group, an acyl group, an amide group, an oxycarbonyl group or a cyano group.)

（上記一般式（３）中、Ｒ^６は、炭素数１〜８のアルキル基、アリール基または芳香族ヘテロ環基を表す。）

(In the general formula (3), R ⁶ represents an alkyl group having 1 to 8 carbon atoms, an aryl group, or an aromatic heterocyclic group.)

  Specific examples of the organic tellurium compound represented by the general formula (2) include 3-methylterranyl-1-propene, 3-methylterranyl-2-methyl-1-propene, and 3-methylterranyl-2-phenyl-1-propene. 3-methyl terranyl-3-methyl-1-propene, 3-methyl terranyl-3-phenyl-1-propene, 3-methyl terranyl-3-cyclohexyl-1-propene, 3-methyl terranyl-3-cyano-1-propene, 3, -Ethyl terranyl-1-propene, 3-methyl terranyl-3-dimethylaminocarbonyl-1-propene, 3-[(n-propyl) terranyl] -1-propene, 3-isopropyl terranyl-1-propene, 3- (n -Butyl) terranylpropene, 3-[(n-hexyl) terranyl] -1-propene, 3-phenylte Nyl-1-propene, 3-[(p-methylphenyl) terranyl] -1-propene, 3-cyclohexylterranyl-1-propene, 3-[(2-pyridyl) terranyl] -1-propene, 3-methylterranyl 2-butene, 3-methylterranyl-1-cyclopentene, 3-methylterranyl-1-cyclohexene, 3-methylterranyl-1-cyclooctene, 3-ethylterranyl-1-cyclohexene, 3-methylterranyl-1-cyclohexene, 3-[( n-propyl) terranyl] -1-cyclohexene, 3-[(n-butyl) terranyl] -1-cyclohexene, methyl 2- (methylterranylmethyl) acrylate, ethyl 2- (methylterranylmethyl) acrylate, 2- (Methylterranylmethyl) acrylate n-butyl, 2- (ethylteranyl) Cyl) methyl acrylate, 2-[(n-butyl) terranylmethyl] methyl acrylate, 2- (cyclohexyl terranylmethyl) acrylate, 1,4-bis (methylterranyl) -2-butene, 1,4-bis (Ethylteranyl) -2-butene, 1,4-bis [(n-butyl) terranyl] -2-butene, 1,4-bis (cyclohexylterranyl) -2-butene, 1,4-bis (phenylterranyl) ) -2-butene, (methylterranylmethyl) benzene, (methylterranylmethyl) naphthalene, ethyl-2-methyl-2-methylterranyl-propionate, ethyl-2-methyl-2-n-butylterranyl-propionate, (2 -Trimethylsiloxyethyl) -2-methyl-2-methylterranyl-propionate, (2-hydroxyethyl) -2 -Methyl-2-methylterranyl-propionate, (3-trimethylsilylpropargyl) -2-methyl-2-methylterranyl-propionate, 2-methylterranyl-isobutyrate and the like.

  Specific examples of the organic ditellurium compound represented by the general formula (3) include dimethyl ditelluride, diethyl ditelluride, di-n-propyl ditelluride, diisopropyl ditelluride, dicyclopropyl ditelluride, Di-n-butylditelluride, di-s-butylditelluride, di-t-butylditelluride, dicyclobutylditelluride, diphenylditelluride, bis- (p-methoxyphenyl) ditelluride, bis- (p-aminophenyl) ditelluride, Bis- (p-nitrophenyl) ditelluride, bis- (p-cyanophenyl) ditelluride, bis- (p-sulfonylphenyl) ditelluride, dinaphthyl ditelluride, dipyridyl ditelluride and the like can be mentioned.

  As the azo polymerization initiator, any azo polymerization initiator used in usual radical polymerization can be used without particular limitation. As a specific example thereof, 2,2′-azobis (isobutyronitrile) can be used. ), 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 1,1′-azobis (1-cyclohexanecarbonitrile), dimethyl-2 , 2′-azobisisobutyrate, 4,4′-azobis (4-cyanovaleric acid), 1,1′-azobis (1-acetoxy-1-phenylethane), 2,2′-azobis (2- Methylbutyramide), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylamidinopropane) dihydrochloride, 2,2'-azo [2- (2-imidazolin-2-yl) propane], 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2′-azobis (2,4,4) 4-trimethylpentane), 2-cyano-2-propylazoformamide, 2,2′-azobis (N-butyl-2-methylpropionamide), 2,2′-azobis (N-cyclohexyl-2-methylpropionamide) ) And the like.

  The amount of the organic tellurium compound represented by the general formula (2) is not particularly limited. However, from the viewpoint of setting the absolute molecular weight of the obtained block copolymer within the above range, the monomer ((meta ) When the acrylate block (α) is first formed, it is a monomer containing a (meth) acrylate monomer including a (meth) acrylate monomer having a cationic group When the aromatic vinyl block (β) is formed first, it is preferably 0.003 to 0.012 mol, more preferably 0 to 1 mol of the monomer containing the aromatic vinyl monomer). 0.004 to 0.009 mol.

  The amount of the azo polymerization initiator used in combination is not particularly limited, but is preferably 75 to 250 mol, more preferably 1 mol of the organic tellurium compound represented by the general formula (2). Is 100-200 mol. Further, the amount of the organic ditellurium compound represented by the general formula (3) used in combination is not particularly limited, but preferably 1 mol of the organic tellurium compound represented by the general formula (2). Is 1.0 to 2.0 mol, more preferably 1.0 to 1.5 mol.

  For example, when an AB type diblock copolymer is obtained by the above method (i), the polymerization is preferably carried out by the following method. That is, a monomer containing an aromatic vinyl monomer is polymerized using a mixture of an organic tellurium compound represented by the above general formula (2) and an azo polymerization initiator as a polymerization initiator. To obtain an aromatic vinyl block (β) having a tellurium functional group at its terminal. Next, an organic ditellurium compound represented by the above general formula (3) as a polymerization initiator and a cationic group are added to the reaction system containing an aromatic vinyl block (β) having a tellurium functional group at the terminal obtained. A monomer containing a (meth) acrylic acid ester monomer including a (meth) acrylic acid ester monomer is added, and the polymerization reaction is continued, whereby the (meth) acrylic acid ester block (α) is added. It can be produced by forming it continuously with the aromatic vinyl block (β).

  In the polymerization reaction, a solvent may be used or a solvent may not be used. When the solvent is used, the solvent used is not particularly limited as long as it is inert in the polymerization reaction and can dissolve the monomer and the polymerization catalyst. Specific examples of the solvent that can be used include aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene; aliphatic hydrocarbons such as n-hexane, n-heptane, and n-octane; cyclohexane, cyclopentane, and methylcyclohexane. And alicyclic hydrocarbons such as; polar solvents such as dimethylformamide, tetrahydrofuran, diethyl ether, and cyclopentyl methyl ether; In addition, these solvents may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  Moreover, although superposition | polymerization temperature is not specifically limited, Preferably it is 30-100 degreeC, More preferably, it is 50-80 degreeC. The polymerization time is not particularly limited, but is preferably 1 minute to 96 hours.

  The block copolymer of the present invention thus obtained is excellent in micro phase separation by self-organization, and can thereby provide a thin film having extremely fine and good micro domains. For example, by forming the block copolymer of the present invention into a film and causing microphase separation by heating or the like, a thin film having extremely fine and good microdomains can be obtained. Although it does not specifically limit as a method to shape | mold into a film form, For example, solvent cast molding, melt extrusion molding, melt compression molding, etc. are mentioned. The annealing temperature in the case of causing microphase separation of the thin film obtained by these methods is not particularly limited, but is preferably 20 to 250 ° C., more preferably 80 to 200 ° C., and the annealing time is preferably 0.8. 1 to 96 hours, more preferably 3 to 24 hours.

  And since the thin film obtained in this way has a very fine and favorable micro domain, porous membrane material, drug delivery system (DDS), polymer carrier, photoresist material, quantum dot, high surface area capacitor It can be suitably used for various applications such as bit pattern media. In particular, when the block copolymer of the present invention can have a lamellar microdomain structure by causing microphase separation by heating or the like, patterning with a very fine line width is possible. Therefore, it can be particularly suitably used as a photoresist material. However, the block copolymer of the present invention is not particularly limited to those capable of forming such a lamellar microdomain structure.

<Block copolymer composition>
Moreover, the block copolymer of this invention is good also as a form of a block copolymer composition by mix | blending compounds other than this block copolymer.

  The compound other than the block copolymer of the present invention used in this case is not particularly limited. For example, a solvent, a polymer other than the block copolymer of the present invention, a photosensitizer, a surfactant, and a silane coupling agent. Sensitizers, light stabilizers, antifoaming agents, pigments, dyes, fillers and the like.

  Examples of the polymer other than the block copolymer of the present invention include, for example, a polystyrene polymer, a poly (meth) acrylic polymer, a polyvinyl acetal polymer, a polyurethane polymer, a polyurea polymer, and a polyamide polymer. Examples include coalesced polymers, polyimide polymers, polyester polymers, and epoxy resins.

  Examples of the photosensitizer include azide compounds such as acetophenone compounds, triarylsulfonium salts, and quinonediazide compounds. Among these, a quinonediazide compound is preferable.

  The compounding amount of the compound other than the block copolymer of the present invention in the block copolymer composition of the present invention depends on the compound to be blended within a range not inhibiting the microphase separation by the block copolymer of the present invention. The amount is not particularly limited.

  The block copolymer composition of the present invention contains the above-described block copolymer of the present invention. Therefore, like the above-described block copolymer of the present invention, the microphase separation property by self-organization is provided. This makes it possible to provide a thin film having extremely fine and good microdomains. And according to the block copolymer composition of the present invention, the block copolymer composition of the present invention is formed into a film like the block copolymer of the present invention described above, and dried if necessary. After removing the solvent by, microphase separation is caused by heating or the like, so that a thin film having extremely fine and good microdomains can be obtained. The annealing temperature and annealing time for causing microphase separation may be the same as those of the block copolymer of the present invention described above.

  And since the thin film obtained in this way has a very fine and favorable micro domain, it can be used suitably for various uses like the thin film obtained using the block copolymer of this invention mentioned above. It can be done.

  Hereinafter, although this invention is demonstrated based on a more detailed Example, this invention is not limited to these Examples. In the following, “part” is based on weight unless otherwise specified. Moreover, the test and evaluation followed the following.

[Number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn)]
The number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn) of the polystyrene block and block copolymer were determined by gel permeation chromatography (GPC) using tetrahydrofuran or dimethylformamide as a solvent. It was measured as a polystyrene equivalent value. In addition, HLC-8320 (manufactured by Tosoh Corporation) is used as a measuring instrument, two columns are used by connecting two TSKgel α-M (manufactured by Tosoh Corporation) in series, and a detector is a differential refractometer RI-8320 (manufactured by Tosoh Corporation). ) Was used.

[Absolute molecular weight (Mabs)]
For the block copolymer, ¹ H-NMR measurement and elemental analysis are performed to configure the number of moles of monomer units (M _MMA ) constituting the poly (methyl methacrylate-cationized methyl methacrylate) block and the polystyrene block. the molar ratio of the moles of the monomer units _{(M ST) of:} calculating the _(M MMA M _ST). Then, from the number average molecular weight (Mn) in terms of polystyrene of the polystyrene block measured as described above and the molar ratio (M _MMA : M _ST ) by ¹ H-NMR measurement and elemental analysis, the absolute molecular weight (Mabs) is calculated. Calculated.

[Content of cationized methyl methacrylate monomer unit]
Structure of cationized methyl methacrylate monomer unit contained in block copolymer, and cationized methyl methacrylate monomer unit in poly (methyl methacrylate-cationized methyl methacrylate) block constituting block copolymer The content of was measured using a nuclear magnetic resonance apparatus (NMR) as follows. That is, first, 30 mg of a block copolymer to be a sample was added to 1.0 mL of deuterated chloroform or deuterated dimethyl sulfoxide and shaken for 1 hour to be uniformly dissolved. And the NMR measurement was performed about the obtained solution, the < ¹ > H-NMR spectrum was obtained, and the structure of the block copolymer was assigned according to the usual method.
Moreover, the content rate of the cationized methyl methacrylate monomer unit in the poly (methyl methacrylate-cationized methyl methacrylate) block which comprises a block copolymer was computed with the following method. That is, first, from the integral value of protons derived from methyl methacrylate monomer units (including cationized methyl methacrylate monomer units) constituting the main chain of the poly (methyl methacrylate-cationized methyl methacrylate) block, the poly ( The number of moles B1 of all methyl methacrylate monomer units (including cationized methyl methacrylate monomer units) constituting the (methyl methacrylate-cationized methyl methacrylate) block was calculated. Next, the number of moles B2 of the cationized methyl methacrylate monomer unit contained in the poly (methyl methacrylate-cationized methyl methacrylate) block was calculated from the integral value of protons derived from the cationic group. And the ratio (percentage) of B2 with respect to B1 was calculated | required as content rate of the cationized methyl methacrylate monomer unit in a poly (methyl methacrylate-cationized methyl methacrylate) block.

[Example 1]
(Production of block copolymer A having a poly (methyl methacrylate-cationized methyl methacrylate) block and a polystyrene block)
In a glass reactor, 26.3 mg (0.16 mmol) of 2,2′-azobisisobutyronitrile and 28 μL (0.16 mmol) of 2-methylterranyl-isobutyrate were weighed, and a stir bar was placed in the glass reactor. . Next, 2.5 g (24 mmol) of styrene was added, the temperature was raised to 60 ° C., and the mixture was stirred at 60 ° C. to perform a polymerization reaction. After the polymerization reaction started, the viscosity of the solution gradually increased. And the polystyrene block which has a tellurium functional group at the terminal was obtained in the form of a solid polymer by continuing the polymerization reaction for 17 hours. Then, a part of the obtained polystyrene block was collected, and the molecular weight in terms of polystyrene was measured by GPC measurement using tetrahydrofuran as a solvent. As a result, the number average molecular weight (Mn) in terms of polystyrene was 14,500, in terms of polystyrene. The weight average molecular weight (Mw) was 17,100, and the molecular weight distribution (Mw / Mn) was 1.18.

Next, in the same glass reactor, 21.8 μL (0.206 mmol) of dimethylditelluride (Te ₂ Me ₂ ) was added to 2.4 g of the polystyrene block having the tellurium functional group at the terminal obtained above. Further, 4.0 mL of dimethylformamide was added, and 271 mg (0.6 mmol) of 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide was dissolved in 0.5 mL of dimethylformamide. Added. Then, 3.0 g (30.3 mmol) of methyl methacrylate was added, and the mixture was shaken with a shaker for 12 hours to obtain a uniform solution. Subsequently, the second polymerization reaction was performed by stirring at 60 ° C., and the polymerization reaction was continued for 21 hours to obtain an orange solution. Chloroform was added to the obtained orange solution and reprecipitated with methanol, and the resulting precipitate was washed several times with methanol and then dried at 60 ° C. for 12 hours in a vacuum dryer. A block having a poly (methyl methacrylate-cationized methyl methacrylate) block and a polystyrene block containing a 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit Copolymer A was obtained.

The yield of the obtained block copolymer A was 3.14 g (57% yield). And when a part of obtained block copolymer A was extract | collected and the molecular weight in polystyrene conversion was measured by GPC measurement which uses dimethylformamide as a solvent, the number average molecular weight (Mn) in polystyrene conversion was 19, 500, molecular weight distribution (Mw / Mn) was 1.48. Further, by ¹ H-NMR measurement and elemental analysis, the number of moles of monomer units (M _MMA ) constituting the poly (methyl methacrylate-cationized methyl methacrylate) block and the moles of monomer units constituting the polystyrene block. When the molar ratio (M _MMA : M _ST ) with the number (M _ST ) was measured, the molar ratio (M _MMA : M _ST ) was M _MMA : M _ST = 0.48: 0.52. Then, from the molar ratio (M _MMA : M _ST ) and the number average molecular weight (Mn) in terms of polystyrene of the polystyrene block by the GPC measurement measured above, the absolute molecular weight (Mabs) of the block copolymer A is about It was confirmed to be 28,000. Further, from ¹ H-NMR measurement, 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit in a poly (methyl methacrylate-cationized methyl methacrylate) block The content ratio of was confirmed to be 2.7 mol%.

[Example 2]
(Production of block copolymer B having a poly (methyl methacrylate-cationized methyl methacrylate) block and a polystyrene block)
The same procedure as in Example 1 was conducted except that the amount of 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide was changed from 271 mg (0.6 mmol) to 135.7 mg (0.3 mmol). And a poly (methyl methacrylate-cationized methyl methacrylate) block containing a 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit, and a polystyrene block. 4.34 g (yield 79%) of block copolymer B was obtained.
The polystyrene block was confirmed to have the same number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn) as in Example 1.

And when a part of obtained block copolymer B was extract | collected and the molecular weight in polystyrene conversion was measured by GPC measurement which uses a dimethylformamide as a solvent, the number average molecular weight (Mn) in polystyrene conversion was 22, 000 and the molecular weight distribution (Mw / Mn) was 1.44. Further, by ¹ H-NMR measurement and elemental analysis, the number of moles of monomer units (M _MMA ) constituting the poly (methyl methacrylate-cationized methyl methacrylate) block and the moles of monomer units constituting the polystyrene block. When the molar ratio (M _MMA : M _ST ) with the number (M _ST ) was measured, the molar ratio (M _MMA : M _ST ) was M _MMA : M _ST = 0.54: 0.46. Then, from the molar ratio (M _MMA : M _ST ) and the number average molecular weight (Mn) in terms of polystyrene of the polystyrene block by the GPC measurement measured above, the absolute molecular weight (Mabs) of the block copolymer B is about It was confirmed to be 31,000. Further, from ¹ H-NMR measurement, 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit in a poly (methyl methacrylate-cationized methyl methacrylate) block The content ratio of was confirmed to be 1.3 mol%.

Example 3
(Production of block copolymer C having a poly (methyl methacrylate-cationized methyl methacrylate) block and a polystyrene block)
Except that the amount of 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide used was changed from 271 mg (0.6 mmol) to 407 mg (0.9 mmol), the same as in Example 1, A block copolymer comprising a poly (methyl methacrylate-cationized methyl methacrylate) block containing a 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit and a polystyrene block. 3.96 g of polymer C (yield 72%) was obtained.
The polystyrene block was confirmed to have the same number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn) as in Example 1.

And when a part of obtained block copolymer C was extract | collected and the molecular weight in polystyrene conversion was measured by the GPC measurement which uses a dimethylformamide as a solvent, the number average molecular weight (Mn) in polystyrene conversion is 15, 000 and the molecular weight distribution (Mw / Mn) was 1.42. Further, by ¹ H-NMR measurement and elemental analysis, the number of moles of monomer units (M _MMA ) constituting the poly (methyl methacrylate-cationized methyl methacrylate) block and the moles of monomer units constituting the polystyrene block. When the molar ratio (M _MMA : M _ST ) with the number (M _ST ) was measured, the molar ratio (M _MMA : M _ST ) was M _MMA : M _ST = 0.50: 0.50. Then, from the molar ratio (M _MMA : M _ST ) and the number average molecular weight (Mn) in terms of polystyrene of the polystyrene block by GPC measurement as described above, the absolute molecular weight (Mabs) of the block copolymer C is about It was confirmed to be 29,000. Further, from ¹ H-NMR measurement, 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit in a poly (methyl methacrylate-cationized methyl methacrylate) block The content ratio of was confirmed to be 3.0 mol%.

[Comparative Example 1]
(Production of block copolymer D having poly (methyl methacrylate-cationized methyl methacrylate) block and polystyrene block)
Except that the amount of 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide used was changed from 271 mg (0.6 mmol) to 679 mg (1.5 mmol), the same as in Example 1, A block copolymer comprising a poly (methyl methacrylate-cationized methyl methacrylate) block containing a 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit and a polystyrene block. 3.66 g of polymer D (yield 67%) was obtained.
The polystyrene block was confirmed to have the same number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn) as in Example 1.

A part of the obtained block copolymer D was collected, and the molecular weight in terms of polystyrene was measured by GPC measurement using dimethylformamide as a solvent. The number average molecular weight (Mn) in terms of polystyrene was 11, 000 and the molecular weight distribution (Mw / Mn) was 1.49. Further, by ¹ H-NMR measurement and elemental analysis, the number of moles of monomer units (M _MMA ) constituting the poly (methyl methacrylate-cationized methyl methacrylate) block and the moles of monomer units constituting the polystyrene block. When the molar ratio (M _MMA : M _ST ) with the number (M _ST ) was measured, the molar ratio (M _MMA : M _ST ) was M _MMA : M _ST = 0.51: 0.49. Then, from the molar ratio (M _MMA : M _ST ) and the number average molecular weight (Mn) in terms of polystyrene of the polystyrene block by the GPC measurement measured above, the absolute molecular weight (Mabs) of the block copolymer D is about It was confirmed to be 29,000. Further, from ¹ H-NMR measurement, 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit in a poly (methyl methacrylate-cationized methyl methacrylate) block The content ratio of was confirmed to be 4.7 mol%.

[Comparative Example 2]
(Production of block copolymer E having a poly (methyl methacrylate-cationized methyl methacrylate) block and a polystyrene block)
The same procedure as in Example 1 was conducted except that the amount of 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide was changed from 271 mg (0.6 mmol) to 27.2 mg (0.06 mmol). And a poly (methyl methacrylate-cationized methyl methacrylate) block containing a 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit, and a polystyrene block. 4.0 g (yield 73%) of block copolymer E was obtained.
The polystyrene block was confirmed to have the same number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn) as in Example 1.

And when a part of obtained block copolymer E was extract | collected and the molecular weight in polystyrene conversion was measured by GPC measurement which uses a dimethylformamide as a solvent, the number average molecular weight (Mn) in polystyrene conversion is 25 ,. 000 and the molecular weight distribution (Mw / Mn) was 1.45. Further, by ¹ H-NMR measurement and elemental analysis, the number of moles of monomer units (M _MMA ) constituting the poly (methyl methacrylate-cationized methyl methacrylate) block and the moles of monomer units constituting the polystyrene block. When the molar ratio (M _MMA : M _ST ) with the number (M _ST ) was measured, the molar ratio (M _MMA : M _ST ) was M _MMA : M _ST = 0.50: 0.50. And, based on the molar ratio (M _MMA : M _ST ) and the number average molecular weight (Mn) in terms of polystyrene of the polystyrene block by the GPC measurement measured above, the absolute molecular weight (Mabs) of the block copolymer E is about It was confirmed to be 29,000. Further, from ¹ H-NMR measurement, 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide unit as a cationized methyl methacrylate unit in a poly (methyl methacrylate-cationized methyl methacrylate) block The content ratio of was confirmed to be 0.2 mol%.

[Comparative Example 3]
(Production of block copolymer F having a polymethyl methacrylate block and a polystyrene block)
Block copolymer F having a polymethyl methacrylate block and a polystyrene block in the same manner as in Example 1 except that 2-[(methacryloyloxy) ethyl] trimethylammonium bis (trifluoromethanesulfonyl) imide was not used. 4.90 g (88% yield) was obtained.
The polystyrene block was confirmed to have the same number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn) as in Example 1.

And when a part of obtained block copolymer F was extract | collected and the molecular weight in polystyrene conversion was measured by GPC measurement which uses dimethylformamide as a solvent, the number average molecular weight (Mn) in polystyrene conversion is 29, 800, molecular weight distribution (Mw / Mn) was 1.18. Further, by ¹ H-NMR measurement and elemental analysis, the number of moles of monomer units constituting the polymethylmethacrylate block (M _MMA ) and the number of moles of monomer units constituting the polystyrene block (M _ST ) When the molar ratio (M _MMA : M _ST ) was measured, the molar ratio (M _MMA : M _ST ) was M _MMA : M _ST = 0.50: 0.50. Then, from the molar ratio (M _MMA : M _ST ) and the number average molecular weight (Mn) in terms of polystyrene of the polystyrene block by GPC measurement measured above, the absolute molecular weight (Mabs) of the block copolymer F is about It was confirmed to be 29,800.

Example 4
800 mg of the block copolymer A obtained in Example 1 was sandwiched between two PET films and further sandwiched between two metal plates from the outside, placed in a heating furnace, and hot-pressed at 140 ° C. Thus, a thin film sample was obtained by causing microphase separation.

  Next, the obtained thin film sample was fixed with an ultraviolet curable resin, subjected to a cross-section treatment with a cryomicrotome at room temperature, and then subjected to a dyeing treatment for 30 minutes using ruthenium oxide, thereby obtaining a measurement sample. .

And about the obtained measurement sample, field emission type transmission electron microscope (FE-TEM) (product name "JEM2100F", the product made by JEOL) is used, and the range of 100 times to 500 times on the conditions of the voltage of 200 kV. As a result of cross-sectional observation, a lamellar microdomain structure formed by microphase separation of the poly (methyl methacrylate-cationized methyl methacrylate) block and the polystyrene block could be confirmed. The pitch width was about 13-14 nm.
In addition, when the obtained measurement sample was used for measurement with a small-angle X-ray diffractometer (product name “NANO-Viewer”, manufactured by Rigaku), a scattering peak of a periodic structure derived from a microdomain structure Was observed.

[Examples 5 and 6]
Instead of the block copolymer A obtained in Example 1, the block copolymer B obtained in Example 2 (Example 5) and the block copolymer C obtained in Example 3 (Example) A measurement sample was obtained in the same manner as in Example 4 except that 6) was used.

The obtained measurement sample was subjected to cross-sectional observation with a field emission transmission electron microscope (FE-TEM) in the same manner as in Example 4. A lamellar microdomain structure formed by microphase separation of the (methyl methacrylate-cationized methyl methacrylate) block and the polystyrene block was confirmed. In any of Examples 5 and 6, the pitch width was about 13 to 14 nm.
Further, using the obtained measurement sample, measurement was performed with a small-angle X-ray diffractometer (product name “NANO-Viewer”, manufactured by Rigaku Corporation). A scattering peak of the periodic structure derived from the structure was observed.

[Comparative Examples 4 to 6]
Instead of the block copolymer A obtained in Example 1, the block copolymer D obtained in Comparative Example 1 (Comparative Example 4) and the block copolymer E obtained in Comparative Example 2 (Comparative Example 5) And a block copolymer F obtained in Comparative Example 3 (Comparative Example 6) were used in the same manner as in Example 4 to obtain a measurement sample.

  And about the obtained measurement sample, when it carried out cross-sectional observation with the field emission type | mold transmission electron microscope (FE-TEM) similarly to Example 4, in any of the comparative examples 4 and 5, it is poly. A lamellar microdomain structure formed by microphase separation of the (methyl methacrylate-cationized methyl methacrylate) block and the polystyrene block could not be confirmed. Also in Comparative Example 6, a lamellar microdomain structure formed by microphase separation of the polymethyl methacrylate block and the polystyrene block could not be confirmed.

  As described above, a (meth) acrylate block (α) containing a (meth) acrylate monomer unit as a main structural unit, and an aromatic containing an aromatic vinyl monomer unit as a main structural unit The vinyl block (β) and the (meth) acrylic acid ester block (α) in the (meth) acrylic acid ester block (α) in a proportion of 0.5 to 4.5 mol% of (meth) acrylic acid ester monomer units It was confirmed that a lamellar ultrafine microdomain structure can be formed according to the block copolymer contained in (Examples 1 to 6). On the other hand, when the proportion of the (meth) acrylic acid ester monomer unit having a cationic group in the (meth) acrylic acid ester block (α) is too small (Comparative Examples 1 and 4) or too large (Comparison) In Examples 2 and 5 and, in addition, when a (meth) acrylate monomer unit having a cationic group is not contained (Comparative Examples 3 and 6), a lamellar ultrafine microdomain structure is not formed. As a result.

Claims (7)

A (meth) acrylate block (α) containing a (meth) acrylate monomer unit as a main structural unit, and an aromatic vinyl block (β) containing an aromatic vinyl monomer unit as a main structural unit A block copolymer comprising:
The (meth) acrylic acid ester block (α) contains a cationic group-containing (meth) acrylic acid ester monomer unit in all repeating units constituting the (meth) acrylic acid ester block (α). A block copolymer contained in a proportion of 5 to 4.5 mol%. The block copolymer according to claim 1, wherein the (meth) acrylic acid ester monomer unit having a cationic group is a monomer unit represented by the following general formula (1).

(In the general formula (1), R ¹ represents a hydrogen atom or a methyl group, A ⁺ represents a cationic group or a cationic group-containing group, X ⁻ represents an arbitrary counter anion, and m represents 0-10. Is an integer.)   The block copolymer according to claim 1 or 2, wherein the cationic group or the cationic group-containing group is a group in which an atom of Group 15 or Group 16 of the periodic table forms an onium cation structure.   The block copolymer according to any one of claims 1 to 3, which has an absolute molecular weight of 15,000 to 50,000.   The block copolymer according to any one of claims 1 to 4, having a molecular weight distribution of 1.0 to 2.0.   The block copolymer composition containing the block copolymer in any one of Claims 1-5, and compounds other than the said block copolymer.   The thin film formed by microphase-separating the block copolymer in any one of Claims 1-5, or the block copolymer composition of Claim 6.