WO2023276741A1

WO2023276741A1 - Hydrogenated conjugated diene graft polymer, method for producing same, polymer composition, molded article, and crosslinked product

Info

Publication number: WO2023276741A1
Application number: PCT/JP2022/024457
Authority: WO
Inventors: 順矢高井; 敦稲富; 淳裕中原
Original assignee: 株式会社クラレ
Priority date: 2021-06-30
Filing date: 2022-06-20
Publication date: 2023-01-05
Also published as: JPWO2023276741A1; TW202313717A

Abstract

Provided are a hydrogenated conjugated diene graft polymer having exceptional affinity for polar materials as well as high thermal stability, and a method for producing the hydrogenated conjugated diene graft polymer.　The hydrogenated conjugated diene graft polymer includes a main chain (a) composed of a polymer including a conjugated diene unit, and a side chain (b) composed of a polymer including at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units, at least some of the carbon-carbon double bonds included in the conjugated diene units being hydrogenated, wherein the side chain (b) is bonded to an atom included in a monomer unit that forms a branched portion in the main chain (a), and a hydroxyl group is bonded to the main chain (a).

Description

Hydrogenated conjugated diene-based graft polymer, method for producing the same, polymer composition, molded product and crosslinked product

The present invention relates to a hydrogenated conjugated diene-based graft polymer having excellent affinity with polar materials and high thermal stability, and a method for producing the same.

Conventionally, it has been known that branched polymers have higher fluidity than linear polymers of the same molecular weight, and have an excellent balance between workability and mechanical properties. For example, the main chain is lithiated by reacting a preliminarily synthesized polymer constituting the main chain with an organic alkali metal compound in the presence of tetramethylethylenediamine, and then the monomers that form the structural units of the side chains are polymerized. Thus, a method of forming a conjugated diene-based graft polymer is known (see Patent Document 1). As another method for synthesizing a graft polymer, a method is known in which a functional group-modified polymer having an epoxy group is reacted with an active terminal of a polymer obtained by polymerizing a monomer to be a structural unit of a side chain ( See Patent Document 2).

U.S. Pat. No. 8,623,980 Japanese Patent Publication No. 49-36957

However, the conjugated diene-based graft polymer described in Patent Document 1 does not have hydroxyl groups that have affinity with polar materials, so there is room for improvement in affinity with polar materials. Further, the conjugated diene-based graft polymer described in Patent Document 2 has excellent affinity with polar materials because it has hydroxyl groups in its main chain, but there is room for improvement in the thermal stability of the polymer.

The present invention has been made in view of the above circumstances, and provides a hydrogenated conjugated diene-based graft polymer having excellent affinity with polar materials and high thermal stability, and the hydrogenated conjugated diene-based graft polymer. It aims at providing the manufacturing method of.

As a result of intensive studies by the present inventors, it was found that at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit is added to the main chain (a) made of a polymer containing a conjugated diene unit. and wherein at least a portion of the carbon-carbon double bonds contained in the conjugated diene units contained in the graft polymer are hydrogenated, to which side chains (b) comprising a polymer comprising The present inventors have found that a hydrogenated conjugated diene-based graft polymer in which a hydroxyl group is bonded to the main chain (a), which is a graft polymer, has excellent affinity with polar materials and high thermal stability. I have perfected my invention.

That is, the present invention provides the following [1] to [11].
[1] A main chain (a) made of a polymer containing a conjugated diene unit, and a side chain made of a polymer containing at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit ( b)
A hydrogenated conjugated diene-based graft polymer in which at least part of the carbon-carbon double bonds contained in the conjugated diene units are hydrogenated,
The side chain (b) binds to an atom contained in a monomer unit that becomes a branched portion contained in the main chain (a),
A hydrogenated conjugated diene-based graft polymer having a hydroxyl group bonded to the main chain (a).
[2] The hydrogenated conjugated diene graft polymer according to [1], wherein 3.0 mol% or more of hydroxyl groups are bonded to the main chain (a).
[3] The hydrogenation according to [1] or [2], wherein 50 mol% or more of the carbon-carbon double bonds contained in the conjugated diene units in the hydrogenated conjugated diene-based graft polymer are hydrogenated. Conjugated diene graft polymer.
[4] The hydrogenated conjugated diene graft polymer according to any one of [1] to [3], wherein the average number of side chains (b) per molecule of the conjugated diene graft polymer is 2 or more.
[5] the atom bonded to the side chain (b) contained in the monomer unit serving as the branched portion is not a heteroatom,
any of [1] to [4], wherein the linking portion containing an atom that binds to the side chain (b) contained in the monomer unit that becomes the branching portion is not an aromatic group derived from an aromatic vinyl compound; The hydrogenated conjugated diene-based graft polymer described above.
[6] (A-1) The anion active site contained in the polymer (M) is lithiated by reacting the polymer (M) containing a conjugated diene unit with an organolithium compound in the presence of a polar compound. process;
(A-2) adding a functionalizing agent to functionalize a portion of the lithiated anion active sites;
(B) adding at least one monomer selected from the group consisting of a conjugated diene and an aromatic vinyl compound to polymerize from the remaining lithiated anionic active sites in the polymer (M) to obtain a main chain (C) a step of forming a side chain on the polymer (M) to produce a conjugated diene-based graft polymer; (D) recovering the obtained conjugated diene graft polymer;
The method for producing a hydrogenated conjugated diene-based graft polymer according to any one of [1] to [5].
[7] Furthermore, after step (A-2),
(A-3) adding a Lewis acid;
The method for producing a hydrogenated conjugated diene-based graft polymer according to [6].
[8] (E) an active terminal polymer represented by the following formula (I) and PX (I)
(In formula (I), P represents a polymer chain containing at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units, and X represents an anionic polymerization active terminal.) ,
A step of reacting with a functional group-modified conjugated diene polymer having an epoxy group to prepare a conjugated diene graft polymer;
(C) hydrogenating at least part of the carbon-carbon double bonds contained in the conjugated diene units in the conjugated diene graft polymer to form a hydrogenated conjugated diene graft polymer; and (D) a step of recovering the obtained hydrogenated conjugated diene-based graft polymer;
The method for producing a hydrogenated conjugated diene-based graft polymer according to any one of [1] to [5].
[9] A polymer composition containing the hydrogenated conjugated diene graft polymer according to any one of [1] to [5].
[10] A molded article obtained by molding the polymer composition according to [9].
[11] A crosslinked product obtained by crosslinking the polymer composition according to [9].

According to the present invention, a hydrogenated conjugated diene-based graft polymer having excellent affinity with polar materials and high thermal stability, and a method for producing the same are provided.

The present invention will be described in detail below.
The hydrogenated conjugated diene-based graft polymer of the present invention comprises a main chain (a) made of a polymer containing a structural unit derived from a conjugated diene (hereinafter also referred to as a conjugated diene unit), a conjugated diene unit and an aromatic vinyl A polymer containing a structural unit (hereinafter also referred to as a monomer unit) derived from at least one monomer selected from the group consisting of a structural unit derived from a compound (hereinafter also referred to as an aromatic vinyl compound unit) comprising a side chain (b) consisting of
A hydrogenated conjugated diene-based graft polymer in which at least part of the carbon-carbon double bonds contained in the conjugated diene units are hydrogenated,
The side chain (b) binds to an atom contained in a monomer unit that becomes a branched portion contained in the main chain (a),
A hydroxyl group is bonded to the main chain (a).
In the present invention, the term "graft polymer" refers to a polymer having a backbone composed of a polymer chain and side chains composed of a polymer chain as branches. The body unit and the monomer unit that constitutes the side chain polymer chain may be the same or different. In the present invention, the hydrogenated conjugated diene-based graft polymer is a graft polymer containing conjugated diene units, and at least part of the carbon-carbon double bonds contained in the conjugated diene units are hydrogenated. It is a graft polymer with

<Main chain (a)>
The hydrogenated conjugated diene-based graft polymer of the present invention has a main chain (a) composed of a polymer containing conjugated diene units. The main chain contained in the hydrogenated conjugated diene-based graft polymer of the present invention refers to the entire structural unit portion derived from all monomers including the conjugated diene constituting the main chain. For example, a method of lithiating the main chain by reacting a pre-synthesized conjugated diene-based polymer described later with an organic alkali metal compound in the presence of tetramethylethylenediamine, and then polymerizing a monomer that becomes the structural unit of the side chain. In the case of manufacturing with, it refers to the entire conjugated diene-based polymer portion synthesized in advance. For example, when the conjugated diene-based polymer synthesized in advance contains a structural unit (butadiene unit) derived from butadiene with a vinyl bond, it is bonded to a carbon atom in the polymer skeleton (-(C-C) _n -). The term "main chain" includes up to the -CH= _CH2 portion.

The main chain (a) contains a conjugated diene unit as a monomer unit constituting the polymer. Examples of conjugated dienes include butadiene, isoprene, farnesene, myrcene, 2,3-dimethylbutadiene, 2-phenylbutadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 1 ,3-octadiene, 1,3-cyclohexadiene, 2-methyl-1,3-octadiene, 1,3,7-octatriene, and chloroprene. Among these conjugated dienes, butadiene, isoprene, farnesene and myrcene are preferred, butadiene and isoprene are more preferred, and butadiene is even more preferred. The conjugated diene to be the conjugated diene unit may be used alone or in combination of two or more.

In one embodiment, the main chain (a) is preferably composed of conjugated diene units in an amount of 40% by mass or more among all the monomer units constituting the polymer. The total content of conjugated diene units is preferably 50 to 100% by mass, more preferably 60 to 100% by mass, based on the total monomer units of the main chain (a).

The main chain (a) comprises at least one monomer selected from the group consisting of butadiene units and isoprene-derived structural units (isoprene units) in at least 40% by mass of the total monomer units constituting the polymer. In one embodiment, it is preferably a body unit. The total content of butadiene units and isoprene units is preferably 50 to 100% by mass, more preferably 60 to 100% by mass, based on the total monomer units constituting the main chain (a).

Examples of monomer units other than butadiene units and isoprene units contained in the main chain (a) include conjugated diene units other than the above-mentioned butadiene units and isoprene units, aromatic vinyl compound units, and the like.

Examples of aromatic vinyl compounds include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-t-butylstyrene, 4-cyclohexylstyrene, 4- Dodecylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 2,4,6-trimethylstyrene, 2-ethyl-4-benzylstyrene, 4-(phenylbutyl)styrene, 1-vinylnaphthalene, 2- Examples include vinylnaphthalene, vinylanthracene, N,N-diethyl-4-aminoethylstyrene, vinylpyridine, 4-methoxystyrene, monochlorostyrene, dichlorostyrene, and divinylbenzene. Among these aromatic vinyl compounds, styrene, 4-methylstyrene and α-methylstyrene are preferred, and styrene and α-methylstyrene are more preferred. The aromatic vinyl compound to be the aromatic vinyl compound unit may be used alone or in combination of two or more.

The content of monomer units other than butadiene units and isoprene units in the main chain (a) is preferably 60% by mass or less, more preferably 50% by mass or less, and even more preferably 40% by mass or less. . For example, when the aromatic vinyl compound unit is not more than the above range, the processability of the obtained hydrogenated conjugated diene graft polymer tends to be improved.

In one embodiment, the number average molecular weight (Mn) of the main chain (a) is preferably 1,000 or more and 1,000,000 or less, more preferably 2,000 or more and 500,000 or less, and 2,000 or more and 100 ,000 or less is more preferable. In the present invention, Mn of the main chain (a) is, for example, a side chain after lithiating the main chain by reacting a previously synthesized conjugated diene-based polymer described later with an organic alkali metal compound in the presence of tetramethylethylenediamine. In the case of production by a method of polymerizing a monomer to be a structural unit of, it is Mn in a state before hydrogenation of a conjugated diene polymer synthesized in advance to be a constituent of the main chain. When the Mn of the main chain (a) is within the above range, when the conjugated diene-based graft polymer is produced by the production method of the present invention, the processability during production is excellent and the economy is favorable. There is a tendency. In the present invention, unless otherwise specified, Mn is the number average molecular weight in terms of standard polystyrene obtained from measurement by gel permeation chromatography (GPC).

In one embodiment, the vinyl content of the main chain (a) is preferably 90 mol% or less, more preferably 70 mol% or less, and even more preferably 60 mol% or less. The vinyl content of the main chain (a) is preferably 0.5 mol % or more, more preferably 1 mol % or more. In the present invention, the “vinyl content” means 1,2-bonds, 3,4-bonds (other than farnesene) in the total 100 mol% of conjugated diene units contained in the conjugated diene-based graft polymer before hydrogenation. case), and 3,13-bonds (in the case of farnesene), and conjugated diene units (with bonds other than 1,4-bonds (other than farnesene) and conjugated diene units). Vinyl content is derived from conjugated diene units linked by 1,2-linkages, 3,4-linkages (for non-farnesene), and 3,13-linkages (for farnesene) using ¹ H-NMR. is calculated from the area ratio of the peak derived from the 1,4-bond (other than farnesene) and 1,13-bond (for farnesene) conjugated diene units. In the present invention, the vinyl content of the hydrogenated conjugated diene-based graft polymer is defined as the vinyl content of the polymer obtained from the bonding form of the conjugated diene units contained in the polymer before hydrogenation.

The vinyl content of the main chain (a) can be designed according to the purpose. As a result, the resulting hydrogenated conjugated diene graft polymer tends to be excellent in fluidity and low-temperature properties. Moreover, when it is 50 mol % or more, the obtained conjugated diene-based graft polymer tends to be excellent in heat resistance. In addition, when the polymer chain before hydrogenation, which is the main chain (a), is composed only of butadiene units, the vinyl content should be 25 mol % or more in order to prevent performance deterioration due to crystallization after hydrogenation. is preferred.

The vinyl content of the main chain (a) can be determined, for example, by reacting a previously synthesized conjugated diene polymer described later with an organic alkali metal compound in the presence of tetramethylethylenediamine to lithiate the main chain, followed by In the case of production by a method of polymerizing a monomer that becomes the structural unit of, the type of solvent used in producing the pre-synthesized conjugated diene polymer that will be the constituent of the main chain (a), if necessary A desired value can be obtained by controlling the polar compound used, the polymerization temperature, and the like.

The glass transition temperature (Tg) of the main chain (a) depends on the vinyl content of the conjugated diene unit in the polymer chain that becomes the main chain (a), the type of the conjugated diene unit, and the content of monomer units other than the conjugated diene unit. Although it may vary depending on the content and the like, -150 to 50°C is preferred, -130 to 50°C is more preferred, and -130 to 30°C is even more preferred. When the Tg is within the above range, for example, it is possible to prevent the viscosity from increasing, which facilitates handling. In the present invention, Tg is the peak top value of DDSC obtained by differential scanning calorimetry (DSC) measurement.

<Side chain (b)>
The hydrogenated conjugated diene-based graft polymer of the present invention has a side chain (b) comprising a polymer containing at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units.

The side chain (b) contains at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units as monomer units constituting the polymer.

Specific examples of the conjugated diene that can constitute the monomer unit of the side chain (b) are the same as the specific examples of the conjugated diene that constitutes the monomer unit of the main chain (a). Among the conjugated dienes that become the conjugated diene units contained in the side chain (b), butadiene, isoprene, farnesene and myrcene are preferred, and butadiene and isoprene are more preferred. The conjugated diene to be the conjugated diene unit may be used alone or in combination of two or more.

Specific examples of the aromatic vinyl compound that can constitute the monomer units of the side chain (b) are the same as the specific examples of the aromatic vinyl compound that can constitute the monomer units of the main chain (a). Among these aromatic vinyl compounds, styrene and α-methylstyrene are preferred. The aromatic vinyl compound to be the aromatic vinyl compound unit may be used alone or in combination of two or more.

The side chain (b) is two or more selected from the group consisting of homopolymers, conjugated dienes, and aromatic vinyl compounds, in which the skeleton of the polymer chain consists of only one type of conjugated diene unit or one type of aromatic vinyl compound unit. or a structural unit derived from one or more monomers selected from the group consisting of conjugated dienes and aromatic vinyl compounds, and one other than conjugated dienes and aromatic vinyl compounds It may be a copolymer composed of structural units derived from at least one kind of vinyl monomer. Moreover, the polymer constituting the side chain (b) may be of one type alone, or may be of two or more types having different structures.

The content of the conjugated diene unit contained in the polymer constituting the side chain (b) is preferably 50% by mass or more, and 70% by mass or more, based on the total monomer units of the side chain (b). More preferably, it is particularly preferably 80% by mass or more, and may be 100% by mass. When the content of the conjugated diene units is 50% by mass or more, the processability of the obtained hydrogenated conjugated diene graft polymer tends to be improved. In addition, the said content means content in the side chain (b) before hydrogenation.

The conjugated diene that can constitute the side chain (b) preferably contains at least one selected from the group consisting of butadiene and isoprene. The total content of butadiene units and isoprene units contained in the polymer constituting the side chain (b) is preferably 50% by mass or more, preferably 70% by mass, of the total monomer units constituting the polymer. % or more, particularly preferably 80 mass % or more, and may be 100 mass %. The mass ratio of butadiene units and isoprene units (butadiene units/isoprene units) contained in the side chain (b) is preferably in the range of 0/100 to 50/50, more preferably in the range of 0/100 to 30/70. A range of 0/100 to 20/80 is particularly preferred. When the total content of butadiene units and isoprene units and the mass ratio of butadiene units to isoprene units in the side chain (b) are within the above ranges, the resulting hydrogenated conjugated diene-based graft polymer has improved processability. There is a tendency. In addition, the said content and mass ratio mean the content and mass ratio in the side chain (b) before hydrogenation.

The content of the aromatic vinyl compound unit contained in the polymer constituting the side chain (b) is preferably 50% by mass or less, preferably 30% by mass, of the total monomer units constituting the polymer. It is more preferably 20% by mass or less, particularly preferably 20% by mass or less, and may be 0% by mass. When the content of the aromatic vinyl compound unit is 50% by mass or less, the resulting hydrogenated conjugated diene graft polymer tends to be improved in processability. In addition, the said content means content in the side chain (b) before hydrogenation.

In one embodiment, the number average molecular weight (Mn) of the side chain (b) is preferably 500 or more and 300,000 or less, more preferably 1,000 or more and 200,000 or less, and 1,000 or more and 150,000 or less. is more preferred. In the present invention, the Mn of the side chain (b) is, for example, a conjugated diene-based polymer synthesized in advance described later, which is lithiated by reacting the main chain with an organic alkali metal compound in the presence of tetramethylethylenediamine. In the case of production by a method of polymerizing a monomer that becomes the structural unit of (macroinitiator method (MI method)), the organic alkali metal compound used in the lithiation reaction and the monomer that becomes the structural unit of the side chain is the Mn in the state before hydrogenation calculated from the charge ratio of . When the Mn of the side chain (b) is within the above range, there is a tendency that the process passability during production is excellent and the economy is favorable.

In one aspect, the vinyl content of the side chain (b) is preferably 99 mol% or less, more preferably 90 mol% or less, and even more preferably 85 mol% or less. The vinyl content of the side chain (b) is preferably 0.5 mol % or more, more preferably 1 mol % or more. The vinyl content of the side chain (b) can be determined, for example, by reacting a conjugated diene-based polymer synthesized in advance, which will be described later, with an organic alkali metal compound in the presence of tetramethylethylenediamine to lithiate the main chain, and then determining the structure of the side chain. In the case of production by a method of polymerizing a monomer to be a unit, the vinyl content of the conjugated diene-based graft polymer before hydrogenation calculated from the ¹ H-NMR spectrum and the vinyl content of the above-mentioned main chain (a) , and from the feed ratio of the monomers that are the raw materials of the monomer units that constitute the main chain and the side chain. When the vinyl content of the side chain (b) is within the above range, the resulting hydrogenated conjugated diene graft polymer tends to have an excellent balance between low-temperature properties and heat resistance. In addition, when the polymer chain before hydrogenation, which is the side chain (b), is composed only of butadiene units, the vinyl content of the side chain (b) is set to 25 in order to prevent performance deterioration due to crystallization after hydrogenation. mol % or more is preferable.

Incidentally, the vinyl content of the side chain (b) can be determined, for example, by reacting a conjugated diene-based polymer synthesized in advance, which will be described later, with an organic alkali metal compound in the presence of tetramethylethylenediamine to lithiate the main chain, followed by In the case of production by a method of polymerizing a monomer that becomes a structural unit of, the type of solvent used when polymerizing the side chain (b), the polar compound or Lewis acid used as necessary, the polymerization temperature A desired value can be obtained by controlling such as.

The glass transition temperature (Tg) of the side chain (b) is determined by the vinyl content of the conjugated diene unit in the polymer chain that becomes the side chain (b), the type of conjugated diene, the content of monomer units other than the conjugated diene unit, and the like. Although it may vary depending on the temperature, -150 to 50°C is preferred, -130 to 50°C is more preferred, and -130 to 30°C is even more preferred. When the Tg is within the above range, for example, it is possible to prevent the viscosity from increasing, which facilitates handling. Here, when the side chain (b) is a block copolymer described later and has two or more Tg, the lowest Tg is preferably within the above range.

The side chain (b) may be a block copolymer chain containing a polymer block (b1) containing an aromatic vinyl compound unit and a polymer block (b2) containing a conjugated diene unit.

The polymer block (b1) contains aromatic vinyl compound units. Specific examples and preferred examples of the aromatic vinyl compound unit are the same as specific examples and preferred examples of the aromatic vinyl compound unit constituting the monomer unit of the side chain (b). In the polymer block (b1), the content of the aromatic vinyl compound unit is preferably more than 70 mol%, more preferably more than It is 80 mol % or more, more preferably 90 mol % or more, still more preferably 95 mol % or more, and particularly preferably substantially 100 mol %.

The polymer block (b1) is a structural unit derived from an unsaturated monomer other than the aromatic vinyl compound (hereinafter referred to as "another unsaturated monomer unit") as long as it does not interfere with the object and effect of the present invention. may be contained in the polymer block (b1) in a proportion of 30 mol% or less, preferably less than 20 mol%, more preferably less than 15 mol%, still more preferably less than 10 mol% , more preferably less than 5 mol %, particularly preferably 0 mol %.

Examples of other unsaturated monomers include butadiene, isoprene, 2,3-dimethylbutadiene, 1,3-pentadiene, 1,3-hexadiene, myrcene, farnesene, isobutylene, methyl methacrylate, methyl vinyl ether, β- At least one selected from the group consisting of pinene, 8,9-p-mentene, dipentene, methylenenorbornene, 2-methylenetetrahydrofuran and the like. When the polymer block (b1) contains the other unsaturated monomer units, the bonding form is not particularly limited, and may be random or tapered.

When the side chain (b) is the block copolymer chain, the Mn of the polymer block (b1) is not particularly limited, but the Mn of the polymer block (b1) is preferably 500 to 300,000, More preferably from 1,000 to 200,000, still more preferably from 1,000 to 50,000. When the chain (b) of the conjugated diene graft polymer has a polymer block (b1) having Mn within the above range, the properties such as shear stability of the oil composition containing the conjugated diene graft polymer are improved. tend to improve.

The content of the polymer block (b1) in the conjugated diene-based graft polymer is preferably 70% by mass or less, more preferably 60% by mass or less, even more preferably 50% by mass or less, 40% by mass or less is particularly preferred. When the content of the polymer block (b1) is equal to or less than the above upper limit, properties such as shear stability of the obtained oil composition containing the conjugated diene-based graft polymer tend to be further improved. The content of the polymer block (b1) is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more. If the content of the polymer block (b1) is at least the above lower limit, the production of the conjugated diene-based graft polymer tends to be easy. The content of the polymer block (b1) in the conjugated diene graft polymer can be determined by ¹ H-NMR measurement.

When the side chain (b) is the block copolymer chain, it should contain at least one polymer block (b1). When the block copolymer chain contains two or more polymer blocks (b1), the polymer blocks (b1) may be the same or different. Further, when the different side chains (b) are also the block copolymer chains, the polymer blocks (b1) contained in these two or more copolymer chains may be the same or different. good. In the present invention, "polymer blocks are different" means the monomer units constituting the polymer blocks, Mw, stereoregularity, and, in the case of having a plurality of monomer units, the ratio of each monomer unit and the form of copolymerization. It means that at least one of (random, gradient, block) is different.

When the side chain (b) is the block copolymer chain, the contained polymer block (b2) contains a conjugated diene compound unit. The content of the conjugated diene unit in the polymer block (b2) is preferably 50 mol% or more, more preferably 70 mol% or more, from the viewpoint of improving the properties of the oil composition containing the conjugated diene-based graft polymer to be obtained. , more preferably 90 mol % or more, and particularly preferably substantially 100 mol %.

The specific examples and preferred examples of the conjugated diene and the content and preferred ratio of each monomer are the specific examples and preferred examples of the conjugated diene constituting the monomer unit of the side chain (b) and each monomer. is the same as the content and preferred ratio of
Examples of compounds include butadiene, isoprene, hexadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, myrcene, farnesene and the like. One of these conjugated diene compounds may be used alone, or two or more thereof may be used.

When the side chain (b) is the block copolymer chain and two or more polymer blocks (b2) are contained, the polymer blocks (b2) may be the same or different. may be Further, when the different chains (b) are also the block copolymer chains, the polymer blocks (b2) contained in these two or more copolymer chains may be the same or different. .

The vinyl content of the conjugated diene units of the polymer block (b2) is preferably 1 to 60 mol%, more preferably 2 to 40 mol%, even more preferably 3 to 30 mol%, and particularly preferably 4 to 20 mol%. be. When the conjugated diene-based graft polymer is produced by the anionic polymerization described later, the vinyl content of the polymer block or polymer chain is determined by the type of solvent used, the polar compound used as necessary, A desired value can be obtained by controlling the polymerization temperature and the like.

The polymer block (b2) may contain structural units derived from monomers other than the conjugated diene compound as long as the objects and effects of the present invention are not hindered. In this case, in the polymer block (b2), the content of structural units derived from monomers other than the conjugated diene compound is preferably less than 50 mol%, more preferably less than 30 mol%, still more preferably 20 It is less than mol %, even more preferably less than 10 mol %, and particularly preferably 0 mol %.

Examples of other monomers include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene, and N-vinylcarbazole. , aromatic vinyl compounds such as vinylnaphthalene and vinylanthracene, and methyl methacrylate, methyl vinyl ether, β-pinene, 8,9-p-mentene, dipentene, methylenenorbornene, 2-methylenetetrahydrofuran, 1,3-cyclopentadiene, At least one compound selected from the group consisting of 1,3-cyclohexadiene, 1,3-cycloheptadiene, 1,3-cyclooctadiene and the like is preferably included.

When the side chain (b) is the above block copolymer chain, the Mn of the polymer block (b2) is the polymer The Mn of block (b2) is preferably from 500 to 300,000, more preferably from 1,000 to 200,000, even more preferably from 1,000 to 50,000.

When the side chain (b) is the block copolymer chain, it should have at least one polymer block (b2). When the block copolymer chain has two or more polymer blocks (b2), the polymer blocks (b2) may be the same or different. Further, when the different chains (b) are also the block copolymer chains, the polymer blocks (b2) contained in these two or more copolymer chains may be the same or different. .

When the side chain (b) is the above-mentioned block copolymer chain, the block copolymer chain may include polymer blocks other than the above polymer blocks (b1) and (b2) as long as the object and effect of the present invention are not hindered. may contain polymer blocks composed of other monomers. When the side chain (b) contains the block copolymer chain, the total content of the polymer block (b1) and the polymer block (b2) with respect to the entire side chain (b) is 90% by mass. It is preferably at least 95% by mass, more preferably at least 95% by mass, and particularly preferably substantially 100% by mass. If it is 90% by mass or more, the physical properties of the obtained conjugated diene-based graft polymer tend to be improved.

When the side chain (b) is the block copolymer chain, the form of bonding is limited as long as the block copolymer chain contains the polymer block (b1) and the polymer block (b2). may be linear, branched, radial, or a combination of two or more of these. Further, these polymer blocks may be directly bonded to each other, or may be indirectly bonded via another polymer block. Among these, the form of bonding between the polymer block (b1) and the polymer block (b2) is preferably such that these polymer blocks are directly bonded to form a straight chain. As an example of such a bond type, the polymer block (b1) is represented by b1 and the polymer block (b2) by b2. a diblock copolymer chain denoted by b2-b1-b2 or b1-b2-b1, a triblock copolymer chain denoted by b2-b1-b2-b1 or b1-b2-b1-b2 Examples include copolymer chains, pentablock copolymer chains represented by b2-b1-b2-b1-b2 or b1-b2-b1-b2-b1.

Among these, the physical properties of the obtained conjugated diene-based graft polymer are likely to be improved and the production is easy. A diblock copolymer chain that is

<Hydrogenated conjugated diene-based graft polymer>
The hydrogenated conjugated diene-based graft polymer of the present invention comprises a main chain (a) composed of a polymer containing a conjugated diene unit, and a structural unit derived from a conjugated diene unit and an aromatic vinyl compound (hereinafter referred to as an aromatic vinyl compound unit A side chain (b) made of a polymer containing a structural unit (hereinafter also referred to as a monomer unit) derived from at least one monomer selected from the group consisting of
A hydrogenated conjugated diene-based graft polymer in which at least part of the carbon-carbon double bonds contained in the conjugated diene units are hydrogenated,
The side chain (b) binds to an atom contained in a monomer unit that becomes a branched portion contained in the main chain (a),
A hydroxyl group is bonded to the main chain (a).

The main chain (a) of the hydrogenated conjugated diene-based graft polymer of the present invention contains a monomer unit serving as a branched portion. A side chain (b) is bonded to an atom included in the branched portion of the main chain (a). The atom attached to the side chain (b) contained in this branched portion is not a heteroatom. Here, the atom bonded to the side chain (b) is not a heteroatom means that the atom is not an atom other than a carbon atom and a hydrogen atom, that is, the atom is a carbon atom or a hydrogen atom ( The atom to which the side chain (b) is attached is actually a carbon atom since it is a branch point). If the branch point to which the side chain (b) is bonded is the heteroatom itself, it is not preferable because shear stability and thermal stability tend to deteriorate.
In addition, the atom contained in the monomer unit that becomes the branched portion and the bond with the side chain (b) refers to the atom that constitutes the monomer unit that becomes the branched portion in the main chain (typically a carbon atom ) and the atom constituting the side chain (b) are bound. The method for bonding the atoms contained in the monomer units forming the branched portion with the side chain (b) will be described in detail below as an example of the method for producing a hydrogenated conjugated diene-based graft polymer. A site containing a carbon atom having anionic activity (hereinafter, a site containing a carbon atom having anionic activity is also referred to as an anion active site) contained in a monomer unit serving as a branched portion of the polymer that becomes the chain (a) A method (MI method) of forming a side chain (b) by addition polymerization of a monomer starting from the lithiated site having anion activity (MI method), A method (coupling method (CP method)) of reacting an epoxy group contained in a monomer unit that becomes a branched part of coalescence with an active terminal of a polymer obtained by polymerizing a monomer that becomes a structural unit of a side chain, etc. is mentioned.

In the hydrogenated conjugated diene-based graft polymer of the present invention, the atoms bonded to the side chain (b) contained in the monomer units forming the branched portion are not heteroatoms. In the hydrogenated conjugated diene-based graft polymer, if the branch point itself at which the main chain and the side chain are bonded is a hetero atom, the shear stability and thermal stability tend to deteriorate, which is not preferable.

For example, the graft polymer described in Japanese Patent No. 5089007 is prepared by preparing a mixture of a polymer having two active terminals constituting the main chain and a polymer having one active terminal constituting the side chain. Then, a coupling agent containing a silicon atom having 3 or more reactive sites is added to the mixture and reacted. A heteroatom such as a silicon atom derived from the coupling agent serves as a branching point connecting the main chain and the side chain. In addition, before filing the present application, the applicant of the present application modifies a polymer that is a component of the main chain synthesized in advance with a compound containing a silicon atom to obtain a functional group-modified polymer, and the functional group-modified polymer and An application has been filed for a technique relating to a method for synthesizing a graft polymer by a method of reacting an active terminal of a polymer obtained by polymerizing a monomer that constitutes a structural unit of a side chain. A heteroatom such as a silicon atom derived from this functional group-modified polymer serves as a branching point that connects the main chain and the side chain.
In the hydrogenated conjugated diene-based graft polymer of the present invention, which will be described later, the branch point contained in the main chain (a) is an atom (typically a carbon atom) that is not a hetero atom, and a side chain (b ). Therefore, in the hydrogenated conjugated diene-based graft polymer of the present invention, unlike the polymer described above, the partial branch point (connection point) where the main chain and the side chain are bonded is not a heteroatom.

In the hydrogenated conjugated diene-based graft polymer of the present invention, the linking portion containing the atom that binds to the side chain (b) contained in the monomer unit serving as the branched portion contained in the main chain (a) is an aromatic vinyl In one preferred embodiment, it is not an aromatic group derived from a compound. Here, the aromatic group is an aromatic ring other than CH ₂ ═CR (R is hydrogen, an optionally substituted alkyl group, or an optionally substituted aryl group) possessed by the aromatic vinyl compound. means a group containing
Here, "the linking portion containing the atom that bonds to the side chain (b) is not an aromatic group derived from an aromatic vinyl compound"
The monomer unit itself that becomes the branched portion contained in the main chain is a structural unit derived from a monomer other than an aromatic vinyl compound (e.g., a conjugated diene), or the unit that becomes the branched portion contained in the main chain Even if the monomer unit itself is an aromatic vinyl compound unit, it means that the side chain (b) is not bound to an atom in the aromatic group of the aromatic vinyl compound.
A specific example will be described below. A site containing a carbon atom having an anionic activity contained in a monomer unit that becomes a branched portion of a polymer that becomes the main chain (a) described later is lithiated, and the lithiated site having an anionic activity is used as a starting point, When a graft polymer is synthesized by a method of addition-polymerizing a monomer to form a side chain (b), the aromatic vinyl compound contained in the polymer that becomes the main chain (a) has, for example, high anionic activity ( In the case of 4-methylstyrene having a substituent group (highly reactive with organolithium compounds), the methyl group portion derived from 4-methylstyrene has high reactivity, and a side chain (b) is attached to the carbon atom of this methyl group. will combine.
On the other hand, in the case of an aromatic vinyl compound that does not have a substituent with high anionic activity in the aromatic group, such as styrene, ₍ --CH.sub.2--CH--) of the styrene unit that forms the skeleton of the main chain (a) The side chain (b) is attached to the portion of CH ₂ included in the moiety adjacent to the CH to which the benzene ring is attached. In this case, the side chain (b) is not bonded to the carbon atom of the styrene-derived benzene ring, and the linking including the atom that bonds to the side chain (b) in the branched portion contained in the main chain (a) The moiety will not be an aromatic group derived from an aromatic vinyl compound.

In the conjugated diene-based graft polymer of the present invention, as described above, the linking portion containing the atom that binds to the side chain (b) included in the monomer unit serving as the branched portion included in the main chain (a) is an aromatic It is preferably not an aromatic group derived from a group vinyl compound. When the linking portion is the above aromatic group, the shear stability and thermal stability are deteriorated.

For example, the graft polymer described in Journal of Polymer Science: Part A: Polymer Chemistry, 2007, 45, 3513 or Japanese Patent No. 5508066 is a macromonomer (a polymer obtained by polymerizing a monomer that becomes a structural unit of a side chain). A macromonomer (obtained by directly reacting an aromatic vinyl compound having a polymerizable functional group other than CH ₂ ═C— bonded to an aromatic group at the active end of the coalescence) and a monomer that forms the structural unit of the main chain. Synthesized by the method of polymerizing Derived from this macromonomer, the linking portion that binds to the side chain (b) contained in the branched portion in the main chain (a) becomes an aromatic group. Then, in the graft polymer of the present invention, as is clear from, for example, one example of the method for producing the graft polymer described in detail below, the side chain (b) contained in the branched portion in the main chain (a) is bonded. A linking moiety is not an aromatic group.

The average number of side chains (b) per molecule of the hydrogenated conjugated diene-based graft polymer is preferably 2 or more, more preferably 4 or more, and even more preferably 5 or more. The average number of side chains (b) per molecule of the hydrogenated conjugated diene-based graft polymer can be obtained, for example, by reacting a previously synthesized conjugated diene-based polymer described later with an organic alkali metal compound in the presence of tetramethylethylenediamine. When the main chain is lithiated and then polymerized to form the structural unit of the side chain, the organic alkali metal used in the lithiation reaction and the conjugated diene polymer that forms the structural unit of the main chain are used. It is calculated from the charging ratio (molar ratio) of coalescence and functionalizing agent. If the average number of side chains (b) per molecule of the hydrogenated conjugated diene graft polymer is less than 2, the flowability of the obtained hydrogenated conjugated diene graft polymer is reduced, resulting in poor workability and mechanical properties. It tends to be out of balance.

In one aspect of the hydrogenated conjugated diene graft polymer of the present invention, the side chain density of the side chain (b) is preferably 1.0 mol % or more, more preferably 2.0 mol % or more. 0 mol % or more is more preferable, and 4.0 mol % or more is even more preferable. If the side chain density of the conjugated diene-based graft polymer is less than 1.0 mol%, the flowability of the obtained hydrogenated conjugated diene-based graft polymer is lowered, and the balance between workability and mechanical properties tends to be poor. .

In this specification, the side chain density of the side chain (b) refers to the average number of side chains (b) per molecule of the hydrogenated conjugated diene graft polymer and the number average molecular weight of the main chain (a) in terms of standard polystyrene. (Mn) is obtained from the following formula (1). The above side chain density is the number of side chains (b) per molecule of the conjugated diene graft polymer with respect to the total number of monomer units, assuming that the main chain polymer is all styrene units. Means the ratio of the average number of threads.
(Side chain density) = (average number of side chains (b) per molecule of hydrogenated conjugated diene graft polymer)/[(number average molecular weight Mn of main chain (a))/(molecular weight of styrene unit)] ×100 (1)
The Mn of the main chain (a) is obtained by, for example, lithiating the main chain by reacting a previously synthesized conjugated diene-based polymer described later with an organic alkali metal compound in the presence of tetramethylethylenediamine, followed by lithiation of the side chain. In the case of production by a method of polymerizing a monomer to be a structural unit, it is Mn in terms of standard polystyrene before hydrogenation of a pre-synthesized conjugated diene polymer to be a constituent element of the main chain.

In the hydrogenated conjugated diene-based graft polymer of the present invention, hydroxyl groups are bonded to the main chain (a). The hydroxyl group is bonded to the main chain (a) directly or through a linking chain. Here, "bonded directly to the main chain (a)" means that a hydroxyl group is directly bonded to a monomer unit constituting the polymer that forms the main chain. Bonding to the main chain (a) through the linking chain means that one end of the linking chain is bonded to a monomer unit constituting the polymer that is the main chain, and a hydroxyl group is attached to the other end of the linking chain. It means that they are directly connected. For example, when a hydroxyl group is bonded to a 1,2-bonded butadiene unit, the case represented by the following formula (I-1) is the case where the hydroxyl group is directly bonded to the main chain, and the following formula (I- 2) is a case where a hydroxyl group is bonded to the main chain through a linking chain (the following formula (I-1) and the following formula (I-2) show the structure when butadiene is hydrogenated. ing).

In formula (I-2) above, R ¹ is a linking chain. R ¹ is a divalent organic group and is an alkylene group having no heteroatom. When the connecting chain contains a heteroatom, particularly when a hydroxyl group is directly bonded to the heteroatom, the shear stability and thermal stability of the conjugated diene-based graft polymer deteriorate.

The average number of hydroxyl groups bonded to the main chain (a) per molecule of the hydrogenated conjugated diene graft polymer is preferably 1 or more, more preferably 2 or more, and further preferably 3 or more. preferable. The average number of hydroxyl groups bonded to the main chain (a) per molecule of the hydrogenated conjugated diene graft polymer is the hydroxyl value of the hydrogenated conjugated diene graft polymer calculated according to JIS K1557-1:2007 ( mgKOH/g) and the standard polystyrene-equivalent number average molecular weight (Mn) of the hydrogenated conjugated diene-based graft polymer are used to obtain the molecular weight (Mn) according to the following formula (2).
(Average number of hydroxyl groups bonded to the main chain (a) per molecule of the hydrogenated conjugated diene graft polymer) = {(hydroxyl value of the hydrogenated conjugated diene graft polymer) / [(molecular weight of potassium hydroxide) × 1000]} × (number average molecular weight Mn of hydrogenated conjugated diene graft polymer) × [(average molecular weight of monomer units contained in hydrogenated conjugated diene graft polymer)/(molecular weight of styrene unit) ] (2)
When the average number of hydroxyl groups bonded to the main chain (a) per molecule of the hydrogenated conjugated diene-based graft polymer is 1 or more, the affinity with polar materials tends to be excellent.

When hydroxyl groups are bonded to the main chain (a) of the hydrogenated conjugated diene-based graft polymer, the concentration of hydroxyl groups bonded to the main chain (a) is preferably 3.0 mol % or more. 0.5 mol % or more is more preferable, and 4.0 mol % or more is even more preferable. When the concentration of hydroxyl groups bonded to the main chain (a) is 3.0 mol % or more, the affinity with polar materials tends to be excellent. In one embodiment, the concentration of hydroxyl groups bonded to the main chain (a) is preferably 100 mol % or less, more preferably 80 mol % or less, and even more preferably 60 mol % or less. When the concentration of hydroxyl groups bonded to the main chain (a) is 100 mol % or less, the affinity with non-polar materials and the solubility in organic solvents tend to be excellent.

The affinity with a polar material is evaluated, for example, by the degree of mixing between the organic phase and the aqueous phase when a solution of a conjugated diene-based graft polymer dissolved in an organic solvent and water (polar material) are mixed and shaken. be able to. When the affinity with the polar material is high, the presence of the conjugated diene-based graft polymer at the interface between the organic phase and the aqueous phase increases the miscibility of the organic phase and the aqueous phase, making separation more difficult. Therefore, the affinity with polar materials can be evaluated by the separability of the organic phase and the aqueous phase.

In this specification, the concentration of hydroxyl groups bonded to the main chain (a) is defined as the average number of hydroxyl groups bonded to the main chain (a) per molecule of the hydrogenated conjugated diene graft polymer and the standard polystyrene of the main chain (a). Calculated from the following formula (3) using the converted number average molecular weight (Mn). Note that the above hydroxyl group concentration is the number of all monomer units when it is assumed that the main chain polymer is all styrene units. means the ratio of the average number of hydroxyl groups to
(Hydroxy group concentration) = (average number of hydroxyl groups bonded to main chain (a) per molecule of conjugated diene graft polymer)/[(number average molecular weight Mn of main chain (a))/(molecular weight of styrene unit) ]×100 (3)
The Mn of the main chain (a) is obtained by, for example, lithiating the main chain by reacting a previously synthesized conjugated diene-based polymer described later with an organic alkali metal compound in the presence of tetramethylethylenediamine, followed by lithiation of the side chain. In the case of production by a method of polymerizing a monomer to be a structural unit, it is Mn in terms of standard polystyrene before hydrogenation of a pre-synthesized conjugated diene polymer to be a constituent of the main chain.

The combination of the polymer serving as the main chain (a) and the polymer serving as the side chain (b) contained in the hydrogenated conjugated diene-based graft polymer is not particularly limited, and may be the same or different, depending on the purpose. It is possible to design The fact that the polymer forming the main chain (a) and the polymer forming the side chain (b) are different means that at least one selected from the group consisting of (i) to (iv) below is different.
(i) The molecular weight of the polymer that forms the main chain (a) is different from the molecular weight of the polymer that forms the side chain (b).
(ii) The type or combination of types of monomer units in the polymer that forms the main chain (a) is different from the type or combination of types of monomer units in the polymer that forms the side chain (b).
(iii) When the main chain (a) and the side chain (b) each contain a plurality of monomer units of the same type, the monomer unit composition ratio of the polymer that becomes the main chain (a) It differs from the monomer unit composition ratio of the polymer that forms the chain (b).
(iv) When the main chain (a) and the side chain (b) each contain a conjugated diene unit, the vinyl content of the conjugated diene unit of the polymer that becomes the main chain (a) is the same as that of the side chain (b). different from the vinyl content of the conjugated diene units of the polymer.

In the hydrogenated conjugated diene-based graft polymer of the present invention, 50% by mass or more of the total monomer units constituting the polymer is at least one monomer unit selected from the group consisting of butadiene units and isoprene units. It is one aspect that is preferable. The total content of butadiene units and isoprene units is more preferably 60 to 100% by mass, more preferably 70 to 100% by mass, based on the total monomer units of the conjugated diene graft polymer.

The content of monomer units other than butadiene units and isoprene units in the hydrogenated conjugated diene-based graft polymer of the present invention is preferably 50% by mass or less, more preferably 40% by mass or less, and 30% by mass. % by mass or less is more preferable. For example, when the aromatic vinyl compound unit is not more than the above range, the processability of the obtained hydrogenated conjugated diene graft polymer tends to be improved.

In the hydrogenated conjugated diene-based graft polymer of the present invention, at least part of the carbon-carbon double bonds contained in the conjugated diene units of the polymer are hydrogenated. In the hydrogenated conjugated diene-based graft polymer of the present invention, from the viewpoint of heat resistance and weather resistance, the carbon-carbon double bond contained in the unit in the conjugated diene in the conjugated diene-based graft polymer before hydrogenation is 50 It is preferable that 60 mol % or more is hydrogenated, and more preferably 70 mol % or more is hydrogenated. Also, the hydrogenation rate is usually 100 mol % or less. Furthermore, the hydrogenation rate (hydrogenation rate) may be substantially 100 mol % (that is, substantially complete hydrogenation). When the hydrogenation rate is 50 mol % or more, the hydrogenated conjugated diene-based graft polymer tends to have excellent heat resistance. The degree of hydrogenation is obtained by calculating the content of carbon-carbon double bonds contained in the conjugated diene units in the polymer before and after hydrogenation using ¹ H-NMR, and then obtaining these contents. value.

In one embodiment, the weight average molecular weight (Mw) of the hydrogenated conjugated diene-based graft polymer of the present invention is preferably from 5,000 to 2,000,000, and from 10,000 to 1,500,000. It is preferably 15,000 or more and 1,000,000 or less. When the Mw of the hydrogenated conjugated diene-based graft polymer is within the above range, there is a tendency that the processability during production is excellent and the economy is favorable. In addition, the processability of the polymer composition containing the hydrogenated conjugated diene-based graft polymer tends to be improved.

The molecular weight distribution (Mw/Mn) of the hydrogenated conjugated diene-based graft polymer of the present invention is preferably 1.0 to 20.0, more preferably 1.0 to 10.0, and further 1.0 to 5.0. Preferably, 1.0 to 2.0 is particularly preferred. When Mw/Mn is within the above range, variation in viscosity of the hydrogenated conjugated diene-based graft polymer is small, which is more preferable. In the present invention, Mn means number average molecular weight, and Mn is the number average molecular weight in terms of standard polystyrene obtained from GPC measurement. Further, the molecular weight distribution (Mw/Mn) means the ratio (Mw/Mn) of the weight average molecular weight (Mw) converted to standard polystyrene and the number average molecular weight (Mn) obtained by GPC measurement.

In one aspect, the vinyl content of the hydrogenated conjugated diene-based graft polymer of the present invention is preferably 99 mol % or less, more preferably 90 mol % or less, and even more preferably 85 mol % or less. The vinyl content of the conjugated diene-based graft polymer is preferably 0.5 mol % or more, more preferably 1 mol % or more. When the vinyl content of the hydrogenated conjugated diene-based graft polymer is within the above range, the resulting hydrogenated conjugated diene-based graft polymer tends to have an excellent balance between low-temperature properties and heat resistance. When the conjugated diene-based graft polymer before hydrogenation is composed only of butadiene units, the vinyl content is preferably 25 mol % or more in order to prevent deterioration in performance due to crystallization after hydrogenation. The vinyl content of the hydrogenated conjugated diene-based graft polymer of the present invention is calculated in the same manner as for the main chain (a) from the ¹ H-NMR spectrum of the conjugated diene-based graft polymer before hydrogenation.

The glass transition temperature (Tg) of the hydrogenated conjugated diene-based graft polymer is determined by the vinyl content of the conjugated diene unit contained in the graft polymer, the type of conjugated diene unit, and the content of monomer units other than the conjugated diene unit. Although it may vary depending on the temperature, -150 to 50°C is preferred, -130 to 50°C is more preferred, and -130 to 30°C is even more preferred. When the Tg is within the above range, for example, it is possible to prevent the viscosity from becoming high, which facilitates handling.

The mass ratio of the main chain to the side chain in the hydrogenated conjugated diene-based graft polymer of the present invention is preferably in the range of 1/99 to 90/10, more preferably in the range of 3/97 to 80/20, and 5/95. A range of ~70/30 is more preferred. When the mass ratio of the main chain to the side chain is within the above range, the processability of the hydrogenated conjugated diene graft polymer tends to be improved.

In the hydrogenated conjugated diene-based graft polymer used in the present invention, the total amount of catalyst residues derived from the polymerization catalyst, hydrogenation catalyst (hydrogenation catalyst), etc. used for its production is in the range of 0 to 500 ppm in terms of metal. is preferred. For example, when an organic alkali metal such as an organic lithium compound as described later is used as a polymerization catalyst for producing a hydrogenated conjugated diene-based graft polymer, an alkali metal such as lithium is included. Further, when a Ziegler catalyst is used as the hydrogenation catalyst in the hydrogenation of the (unhydrogenated) conjugated diene-based graft polymer described later, nickel and aluminum are included. When the amount of the catalyst residue is within the above range, the tack does not decrease during processing, etc., and the heat resistance of the hydrogenated conjugated diene-based graft polymer used in the present invention is improved. The total amount of catalyst residue in the hydrogenated conjugated diene-based graft polymer is more preferably 0 to 300 ppm, more preferably 0 to 200 ppm in terms of metal. The catalyst residue amount can be measured by using, for example, an inductively coupled plasma mass spectrometer (ICP-MS) or a polarized Zeeman atomic absorption spectrophotometer.

Examples of methods for adjusting the catalyst residue amount of the hydrogenated conjugated diene-based graft polymer to such a specific amount include a method of purifying the hydrogenated conjugated diene-based graft polymer and sufficiently removing the catalyst residue. As a purification method, washing with water or hot water, an acidic aqueous solution, or an organic solvent typified by methanol, acetone, etc., or washing with a supercritical fluid carbon dioxide is preferable. Cleaning efficiency can be further enhanced by using an acidic aqueous solution for cleaning. Acids used include, for example, monovalent or polyvalent strong acids such as hydrochloric acid, nitric acid, and sulfuric acid; monovalent or polyvalent carboxylic acids such as acetic acid, propionic acid, succinic acid, and citric acid; Or polyvalent weak acids are preferred. The number of washings is preferably from 1 to 20 times, more preferably from 1 to 10 times, from an economical point of view. The washing temperature is preferably 20 to 100°C, more preferably 40 to 90°C. In addition, by removing impurities that inhibit polymerization by distillation or an adsorbent before the polymerization reaction and increasing the purity of the monomers, the necessary amount of the polymerization catalyst can be reduced. The catalyst residue amount can be reduced.

<Method for producing hydrogenated conjugated diene-based graft polymer>
In the method for producing a hydrogenated conjugated diene-based graft polymer of the present invention, from the viewpoint of synthesizing a hydrogenated conjugated diene-based graft polymer having a suitable structure, a previously synthesized conjugated diene-based polymer is prepared in the presence of tetramethylethylenediamine. After the main chain is lithiated by reacting with an organic alkali metal compound, a functionalizing agent is added to add hydroxyl groups to some of the lithiation sites, and then the monomers that become the structural units of the side chains are added. A method of polymerizing (hereinafter referred to as a macroinitiator method (MI method) in this specification), or an epoxy contained in a monomer unit that becomes a branched portion of a functional group-modified polymer that becomes the main chain (a) A method of reacting a group with an active terminal of a polymer obtained by polymerizing a monomer constituting a structural unit of a side chain (hereinafter referred to as a coupling method (CP method)) is preferred.

<Macro initiator method (MI method)>
As a method for producing a hydrogenated conjugated diene-based graft polymer of the present invention, a macro comprising the following steps (A-1), (A-2), (B), (C), and (D) A preferred embodiment is a production method by an initiator method (MI method).

(A-1) A step of lithiating anion active sites contained in the polymer (M) by reacting the polymer (M) containing a conjugated diene unit with an organolithium compound in the presence of a polar compound; A-2) adding a functionalizing agent to functionalize a portion of the lithiated anionic active sites; and (B) at least one monomer selected from the group consisting of conjugated dienes and aromatic vinyl compounds. is added to polymerize from the remaining lithiated anion-active sites in the polymer (M) to form side chains with respect to the polymer (M) containing the conjugated diene unit serving as the main chain. and (C) hydrogenating at least part of the carbon-carbon double bonds contained in the conjugated diene units contained in the conjugated diene graft polymer to produce a conjugated diene graft polymer. forming a conjugated diene-based graft polymer; and (D) recovering the obtained hydrogenated conjugated diene-based graft polymer.

[Step (A-1)]
The method for producing the polymer (M) containing a conjugated diene unit that is a constituent of the main chain in the step (A-1) is preferably, for example, an emulsion polymerization method or a solution polymerization method. From the point of view, the solution polymerization method is more preferable. The polymer (M) containing conjugated diene units forms the main chain (a) of the hydrogenated conjugated diene-based graft polymer of the present invention.

Specific examples and preferred examples of the conjugated diene, which is a monomer unit constituting the polymer (M) containing a conjugated diene unit, and description of the preferred content thereof are given in the main chain (a ).

Examples of monomers other than conjugated dienes that are monomer units constituting the polymer (M) containing conjugated diene units include aromatic vinyl compounds.

Examples of aromatic vinyl compounds include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-t-butylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 2,4,6-trimethylstyrene, 2-ethyl-4-benzylstyrene, 4-(phenylbutyl)styrene, 1-vinylnaphthalene, 2-vinylnaphthalene, vinylanthracene, N,N- Diethyl-4-aminoethylstyrene, vinylpyridine, 4-methoxystyrene, monochlorostyrene, dichlorostyrene, divinylbenzene and the like. Among these aromatic vinyl compounds, styrene and α-methylstyrene are preferred. The aromatic vinyl compound to be the aromatic vinyl compound unit may be used alone or in combination of two or more.

The content of monomer units other than butadiene units and isoprene units in the polymer (M) containing a conjugated diene unit is preferably 60% by mass or less, more preferably 50% by mass or less, and 40% by mass. % or less is more preferable. For example, when the aromatic vinyl compound unit is not more than the above range, the processability of the obtained hydrogenated conjugated diene graft polymer tends to be improved.

Descriptions of the number average molecular weight (Mn), vinyl content, suitable aspects of Tg, etc. of the polymer (M) containing conjugated diene units are the same as those for the main chain (a) of the hydrogenated conjugated diene graft polymer. .

As the emulsion polymerization method, which is an example of the method for producing the polymer (M) containing conjugated diene units, a known method or a method based on a known method can be applied. For example, a monomer containing a predetermined amount of conjugated diene is emulsified and dispersed in a dispersion medium in the presence of an emulsifier, and emulsion polymerized with a radical polymerization initiator.

Examples of emulsifiers include salts of long-chain fatty acids with 10 or more carbon atoms and rosinates. Examples of long-chain fatty acid salts include potassium salts or sodium salts of fatty acids such as capric acid, lauric acid, myristic acid, palmitic acid, oleic acid and stearic acid.

Water is usually used as the dispersion medium. The dispersion medium may contain a water-soluble organic solvent such as methanol or ethanol as long as the stability during polymerization is not impaired.

Examples of radical polymerization initiators include persulfates such as ammonium persulfate and potassium persulfate, organic peroxides, and hydrogen peroxide.

A chain transfer agent may be used to adjust the molecular weight of the resulting polymer (M) containing conjugated diene units. Examples of chain transfer agents include mercaptans such as t-dodecylmercaptan and n-dodecylmercaptan; carbon tetrachloride, thioglycolic acid, diterpene, terpinolene, γ-terpinene, α-methylstyrene dimer and the like.

The temperature for emulsion polymerization can be appropriately set depending on the type of radical polymerization initiator to be used, but it is usually in the range of 0 to 100°C, preferably 0 to 60°C. The polymerization mode may be either continuous polymerization or batch polymerization.

The polymerization reaction can be stopped by adding a polymerization terminator. Examples of the polymerization terminator include amine compounds such as isopropylhydroxylamine, diethylhydroxylamine and hydroxylamine, quinone compounds such as hydroquinone and benzoquinone, and sodium nitrite.

After stopping the polymerization reaction, an anti-aging agent may be added as necessary. After stopping the polymerization reaction, unreacted monomers are removed from the obtained latex if necessary, and then salts such as sodium chloride, calcium chloride and potassium chloride are used as coagulants, and if necessary nitric acid, sulfuric acid and the like are added. After the polymer (M) containing the conjugated diene unit is coagulated while adjusting the pH of the coagulation system to a predetermined value by adding an acid, the polymer is recovered by separating the dispersion medium. Then, the polymer (M) containing the conjugated diene unit is obtained by washing with water, dehydration, and drying. At the time of coagulation, if necessary, the latex and an extender oil made into an emulsified dispersion may be mixed in advance, and the polymer (M) containing an oil-extended conjugated diene unit may be recovered.

As the solution polymerization method, which is an example of the method for producing the polymer (M) containing conjugated diene units, a known method or a method based on the known method can be applied. For example, in a solvent, using a Ziegler-based catalyst, a metallocene-based catalyst, or an anionically polymerizable active metal or active metal compound as an initiator, optionally in the presence of a polar compound, a monomer containing a conjugated diene Polymerize the body.

Examples of solvents include aliphatic hydrocarbons such as n-butane, n-pentane, isopentane, n-hexane, n-heptane and isooctane; alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclopentane; Aromatic hydrocarbons such as toluene and xylene; ether compounds such as dibutyl ether, tetrahydrofuran and ethylene glycol diethyl ether;

The initiator is preferably an anionically polymerizable active metal or an active metal compound, more preferably an anionically polymerizable active metal compound.

Examples of anionically polymerizable active metals include alkali metals such as lithium, sodium and potassium; alkaline earth metals such as beryllium, magnesium, calcium, strontium and barium; lanthanoid rare earth metals such as lanthanum and neodymium. . Among these, alkali metals and alkaline earth metals are preferred, and alkali metals are more preferred.

An organic alkali metal compound is preferable as the anionically polymerizable active metal compound. Examples of organic alkali metal compounds include organic monolithium compounds such as methyllithium, ethyllithium, n-butyllithium, sec-butyllithium, t-butyllithium, hexyllithium, phenyllithium, and stilbenelithium; , 1,4-dilithiobutane, 1,4-dilithio-2-ethylcyclohexane and 1,3,5-trilithiobenzene; and sodium naphthalene, potassium naphthalene and the like. Among these organic alkali metal compounds, organic lithium compounds are preferred, and organic monolithium compounds are more preferred.

The amount of the initiator to be used can be appropriately set according to the melt viscosity, molecular weight, etc. of the polymer (M) containing the conjugated diene unit. It is used in an amount of 01 to 3 parts by weight.

When an organic alkali metal compound is used as an initiator, the organic alkali metal compound can be used as an organic alkali metal amide by reacting it with a secondary amine such as dibutylamine, dihexylamine or dibenzylamine. .

Polar compounds are usually used in anionic polymerizations to adjust the microstructure (vinyl content) of the conjugated diene units without inactivating the reaction. Examples of polar compounds include ether compounds such as dibutyl ether, tetrahydrofuran and ethylene glycol diethyl ether; tertiary amines such as tetramethylethylenediamine and trimethylamine; alkali metal alkoxides and phosphine compounds. The polar compound is generally used in an amount of 0.01 to 1000 mol per 1 mol of the organic alkali metal compound.

The temperature of solution polymerization is usually in the range of -80 to 150°C, preferably in the range of 0 to 100°C, more preferably in the range of 10 to 90°C. The mode of polymerization may be either a batchwise system or a continuous system.

The polymerization reaction of the above solution polymerization can be terminated by adding a polymerization terminator. Examples of the polymerization terminator include alcohols such as methanol and isopropanol. The obtained polymerization reaction solution is poured into a poor solvent such as methanol to precipitate a polymer (M) containing a conjugated diene unit, or the polymerization reaction solution is washed with water, separated, and dried to obtain the conjugated diene. A polymer (M) containing units can be isolated. In addition, the polymerization reaction solution after termination of the polymerization may be directly used for the lithiation reaction as long as it does not affect the lithiation reaction. Moreover, if necessary, the solvent may be partly removed, or the solvent may be added to dilute the polymerization reaction solution.

The polymer (M) containing conjugated diene units thus obtained may be used as it is for the lithiation reaction, but the carbon-carbon double bond contained in the conjugated diene unit in the conjugated diene polymer may be modified after at least a part of is hydrogenated by the hydrogenation method described below.

In the step (A-1), the anion active site contained in the polymer (M) containing the conjugated diene unit obtained as described above is lithiated by reacting it with an organolithium compound in the presence of a polar compound. do.
Lithiation under such conditions lithiates the anion active sites, especially the carbon-carbon double bond portion contained in the vinyl bond type conjugated diene unit contained in the polymer (M). In particular, the skeleton of the main chain (a) of the aromatic vinyl compound unit, for example, the styrene unit, which does not have a substituent in the aromatic group having high reactivity with respect to the anion contained in the polymer (M) The CH ₂ moiety adjacent to the CH to which the benzene ring is attached, included in the (--CH ₂ --CH--) moiety, is lithiated.
In the graft polymer obtained by this production method, therefore, the linking portion containing the atom that bonds to the side chain (b) contained in the monomer unit that becomes the branch portion is not an aromatic group derived from the aromatic vinyl compound. . In order to more reliably lithiate a conjugated diene unit containing a site having anionic activity, when the polymer (M) contains an aromatic vinyl compound unit, the aromatic vinyl compound unit has an anionic activity. It is desirable that the aromatic group does not contain a functional group with a high D (a functional group highly reactive with the organolithium compound). Styrenes having aromatic groups containing such functional groups include 4-methylstyrene, 4-propylstyrene, and the like.

Examples of the organic lithium compound used for lithiation of the polymer (M) in the step (A-1) include methyllithium, ethyllithium, n-butyllithium, sec-butyllithium, t-butyllithium, hexyllithium, organic monolithium compounds such as phenyllithium and stilbenelithium; lithium compounds; Among these organic lithium compounds, organic monolithium compounds are preferred, n-butyllithium and sec-butyllithium are more preferred, and sec-butyllithium is particularly preferred.

The amount of the organolithium compound used can be appropriately set according to the average number of side chains (b) of the hydrogenated conjugated diene graft polymer and the average number of hydroxyl groups bonded to the main chain (a). For example, (amount of organolithium compound charged (number of moles))/(amount of functionalizing agent used in the functionalization reaction (number of moles))/(amount of polymer (M) containing conjugated diene units charged (moles number))=10/4/1, the average number of side chains (b) is six. Also, the average number of hydroxyl groups can be designed to be four.

As described above, the side chain density is obtained from the following formula (1).
(Side chain density) = (average number of side chains (b) per molecule of hydrogenated conjugated diene graft polymer)/[(number average molecular weight Mn of main chain (a))/(molecular weight of styrene unit)] ×100 (1)
That is, the amount of the organolithium compound used is determined so that the desired side chain density and hydroxyl group concentration are obtained by adjusting the number average molecular weight Mn of the main chain (a) and the side chain per molecule of the hydrogenated conjugated diene graft polymer. It can be naturally determined by designing the average number of (b) and the average number of hydroxyl groups bonded to the main chain (a).

The polar compound used in the lithiation of the polymer (M) in step (A-1) above is used to promote the lithiation reaction. Examples of polar compounds include ether compounds such as dibutyl ether, tetrahydrofuran and ethylene glycol diethyl ether; tertiary amines such as tetramethylethylenediamine and trimethylamine; alkali metal alkoxides and phosphine compounds. Among these polar compounds, tertiary amines are preferred, and tetramethylethylenediamine is particularly preferred. The amount of the polar compound used is preferably 0.01 mol or more, more preferably 0.05 mol or more, and particularly preferably 0.1 mol or more, relative to 1 mol of the organic alkali metal compound. The amount of the polar compound used is preferably 100 mol or less, more preferably 50 mol or less, and particularly preferably 10 mol or less, per 1 mol of the organic alkali metal compound. When the amount of the polar compound used is less than 0.01 mol per 1 mol of the organic alkali metal compound, the reaction rate tends to be poor, and when it exceeds 100 mol, the economy tends to be poor.

The lithiation in the above step (A-1) is usually carried out with the polymer (M) dissolved in a solvent. Examples of the solvent include aliphatic hydrocarbons such as n-butane, n-pentane, isopentane, n-hexane, n-heptane and isooctane; alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclopentane; and benzene. , toluene, and xylene; and ether compounds such as dibutyl ether, tetrahydrofuran, and ethylene glycol diethyl ether.

The reaction temperature for the lithiation in step (A-1) is preferably 0°C or higher, more preferably 10°C or higher, and particularly preferably 20°C or higher. Also, the temperature is preferably 100° C. or lower, more preferably 80° C. or lower, and particularly preferably 60° C. or lower. If the temperature is less than 0°C, the reaction rate tends to be poor, and if it exceeds 100°C, side reactions such as decomposition tend to increase.

The reaction time of the lithiation in the step (A-1) can be appropriately set according to the progress of the reaction, preferably 0.01 to 100 hours, more preferably 0.1 to 50 hours, and 0.2 to 20 hours. Time is particularly preferred.

In the ¹ H-NMR measurement of the polymer (M) after lithiation in step (A-1), when the peak area in the range of 4.0 to 5.7 ppm is taken as 100, 5.7 to 6.4 ppm is preferably in the range of 0.1 to 10, more preferably in the range of 0.3 to 5, and particularly preferably in the range of 0.5 to 4. When the peak area is within this range, it can be said that the lithiation reaction is progressing properly, and the average number of side chains (b) in the obtained hydrogenated conjugated diene graft polymer is within the proper range.

[Step (A-2)]
In the method for producing a conjugated diene-based graft polymer by the MI method, in order to form hydroxyl groups bonded to the main chain (a), after step (A-1),
(A-2) adding a functionalizing agent to functionalize a portion of the lithiated anion active sites;
including.

In step (A-2), the finally obtained hydrogenated conjugated diene-based graft is reacted with a functionalizing agent with part of the lithiated anionic active sites obtained in step (A-1). Forms a hydroxyl group that bonds to the main chain (a) of the polymer. When a hydroxyl group is formed by this synthesis method, the hydroxyl group is bonded to the main chain (a) through a linking chain.

Examples of the functionalizing agent used in the functionalization reaction of the anion active site lithiated in the above step (A-2) include formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, valeraldehyde, and isovaleraldehyde. , n-octylaldehyde, 2-ethylhexylaldehyde, decylaldehyde, dodecylaldehyde, benzaldehyde; and epoxides such as ethylene oxide and propylene oxide. Among these functionalizing agents, aldehydes such as n-butyraldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, n-octylaldehyde, 2-ethylhexylaldehyde, decylaldehyde, dodecylaldehyde, benzaldehyde are preferred, and 2-ethylhexylaldehyde, Benzaldehyde is particularly preferred.

The amount of the functionalizing agent used can be appropriately set according to the average number of hydroxyl groups bonded to the main chain (a) described above. For example, (amount of organolithium compound charged (number of moles))/(amount of functionalizing agent used in the functionalization reaction (number of moles))/(amount of polymer (M) containing conjugated diene units charged (moles number))=10/4/1, the average number of side chains (b) is six. Also, the average number of hydroxyl groups can be designed to be four.

As described above, the hydroxyl group concentration is obtained from the following formula (3).
(Hydroxy group concentration) = (average number of hydroxyl groups bonded to main chain (a) per molecule of hydrogenated conjugated diene graft polymer)/[(number average molecular weight of main chain (a) Mn)/(number of styrene units molecular weight)] × 100 (3)
That is, the amount of the functionalizing agent used is such that the number average molecular weight Mn of the main chain (a) and the main chain (a) per molecule of the hydrogenated conjugated diene graft polymer are adjusted so as to achieve the desired hydroxyl group concentration. By designing the average number of bonded hydroxyl groups, it can be determined naturally.

The solvent that can be used in the step (A-2) above is the same as the preferred examples of the solvent in the step (A-1) above. If necessary, a solvent may be further added at any timing after step (A-1).

The reaction temperature for the functionalization in step (A-2) is preferably 0°C or higher, more preferably 10°C or higher, and particularly preferably 20°C or higher. Moreover, the reaction temperature is preferably 100° C. or lower, more preferably 80° C. or lower, and particularly preferably 60° C. or lower. If the temperature is less than 0°C, the reaction rate tends to be poor, and if it exceeds 100°C, side reactions such as decomposition tend to increase.

The reaction time of the functionalization in the above step (A-2) can be appropriately set according to the progress of the reaction, preferably 0.01 to 100 hours, more preferably 0.05 to 50 hours, and 0.1 to 20 hours. Time is particularly preferred.

[Step (A-3)]
In the method for producing a hydrogenated conjugated diene-based graft polymer by the MI method, in order to adjust the vinyl content of the side chain (b) to the desired range, after step (A-1) or step (A-2) ,
(A-3) adding a Lewis acid;
It is a preferred embodiment to include

The Lewis acid is added to reduce the action of the polar compound added to promote the lithiation reaction and to adjust the vinyl content of the side chain in the step (B) described below to the desired range. The Lewis acid is preferably an alkyl metal compound that does not deactivate the lithiation point generated in the above step (A-1), such as trimethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, triisobutyl. Alkylaluminum compounds such as aluminum, tri-n-hexylaluminum, and trioctylaluminum; alkylmagnesium compounds such as butylethylmagnesium, di-n-butylmagnesium, and di-n-hexylmagnesium; dimethyl zinc, Alkyl zinc compounds such as diethyl zinc, di-n-propyl zinc, diisobutyl zinc, and di-n-butyl zinc are included. Among these alkyl metal compounds, alkylaluminum compounds or alkylzinc compounds are preferred, alkylaluminum compounds are more preferred, and triisobutylaluminum is particularly preferred.

The amount of the Lewis acid to be used can be appropriately adjusted depending on the vinyl content of the desired side chain (b). is preferred, 0.05 mol or more is more preferred, and 0.1 mol or more is particularly preferred. The amount of the Lewis acid used is preferably 10 mol or less, more preferably 5 mol or less, and particularly preferably 1 mol or less, per 1 mol of the organic alkali metal compound. If the amount of the Lewis acid used relative to 1 mol of the organic alkali metal compound is less than 0.01 mol, the effect of the addition of the Lewis acid is poor and it is difficult to adjust the desired degree of vinylation. The rate of chain polymerization tends to decrease, and the economy tends to be poor. The amount of the Lewis acid used is preferably 0.02 mol or more, more preferably 0.1 mol or more, and 0.2 mol or more, relative to 1 mol of the polar compound used in the step (A-1). Especially preferred. The amount of the Lewis acid to be used is preferably 20 mol or less, more preferably 10 mol or less, and particularly preferably 2 mol or less, relative to 1 mol of the polar compound. If the amount of the Lewis acid used relative to 1 mol of the polar compound is less than 0.02 mol, the effect of adding the Lewis acid is poor and it is difficult to adjust the degree of vinylation to the desired degree. The polymerization rate tends to decrease, and the economy tends to be poor.

The timing of adding the Lewis acid may be after step (A-1), before step (B) described later, or at any timing during step (B). Well, it can be arbitrarily selected depending on the vinyl content of the desired side chain (b).

[Step (B)]
A method for producing a hydrogenated conjugated diene-based graft polymer by the MI method,
(B) adding at least one monomer selected from the group consisting of a conjugated diene and an aromatic vinyl compound to polymerize from the remaining lithiated anionic active sites in the polymer (M) to obtain a main chain A step of forming a side chain on the polymer (M) to produce a conjugated diene-based graft polymer;
including. The monomer polymerized in the step (B) becomes the side chain (b) of the hydrogenated conjugated diene graft polymer of the present invention. Specific examples and preferred examples of the conjugated diene, which is a monomer unit constituting the polymer polymerized in the step (B), preferred content thereof, and other monomers other than the conjugated diene (aromatic vinyl compound etc.) are the same as those for the side chain (b) of the hydrogenated conjugated diene graft polymer. In addition, the description of the weight average molecular weight (Mn), vinyl content, preferred aspects of Tg, etc. of the polymer polymerized in the step (B) is the same as the description of the side chain (b) of the hydrogenated conjugated diene graft polymer. is.

In the above step (B), a polar compound may be further added in order to adjust the vinyl content of the side chain (b) to the desired range. A Lewis acid may also be added as described above to adjust the vinyl content to the desired range.

Solvents that can be used in the step (B) are the same as the preferred examples of the solvent in the step (A-1). If necessary, a solvent may be further added at any timing after step (A-1).

The polymerization temperature in the step (B) is preferably 0°C or higher, more preferably 10°C or higher, and particularly preferably 20°C or higher. The polymerization temperature is preferably 100° C. or lower, more preferably 80° C. or lower, and particularly preferably 60° C. or lower. If the polymerization temperature is less than 0°C, the polymerization rate tends to be poor, and if it exceeds 100°C, side reactions such as decomposition tend to increase.

The polymerization time in the step (B) can be appropriately set according to the progress of the reaction, but is preferably 0.01 to 100 hours, more preferably 0.1 to 50 hours, and particularly preferably 0.2 to 20 hours. .

The polymerization reaction in the above step (B) can be terminated by adding a polymerization terminator. Examples of the polymerization terminator include alcohols such as methanol and isopropanol.

[Step (C)]
In the method for producing a hydrogenated conjugated diene-based graft polymer of the present invention by the MI method, before the step (D),
(C) hydrogenating at least part of the carbon-carbon double bonds contained in the conjugated diene units in the unhydrogenated conjugated diene graft polymer to form a hydrogenated conjugated diene graft polymer;
including.

A hydrogenated conjugated diene graft polymer can be obtained by subjecting the unhydrogenated conjugated diene graft polymer obtained by the above method to a step of hydrogenating. The hydrogenation method is not particularly limited, and for example, a known method can be used. The above step (B) and hydrogenation may be carried out successively, or the unhydrogenated conjugated diene-based graft polymer may be isolated once and then hydrogenated. The method for isolating the unhydrogenated conjugated diene-based graft polymer is the same as the recovery step (D) described below.

As the catalyst used for the hydrogenation reaction in step (C), a catalyst that can hydrogenate carbon-carbon double bonds contained in olefin compounds and the like can be used. Such catalysts generally include heterogeneous catalysts, homogeneous catalysts, and the like.

The heterogeneous catalyst is not particularly limited, but specific examples include sponge metal catalysts such as sponge nickel, sponge cobalt, and sponge copper; nickel silica, nickel alumina, nickel zeolite, nickel diatomaceous earth, palladium silica, palladium alumina, palladium Zeolite, palladium diatomaceous earth, palladium carbon, palladium calcium carbonate, platinum silica, platinum alumina, platinum zeolite, platinum diatomaceous earth, platinum carbon, platinum calcium carbonate, ruthenium silica, ruthenium alumina, ruthenium zeolite, ruthenium diatomaceous earth, ruthenium carbon, ruthenium calcium carbonate, supported metal catalysts such as iridium silica, iridium alumina, iridium zeolite, iridium diatomaceous earth, iridium carbon, iridium calcium carbonate, cobalt silica, cobalt alumina, cobalt zeolite, cobalt diatomaceous earth, cobalt carbon, and cobalt calcium carbonate;
These heterogeneous catalysts may be modified with iron, molybdenum, magnesium or the like for the purpose of improving activity, improving selectivity and stability. These heterogeneous catalysts may be used singly or in combination of two or more.

The homogeneous catalyst is not particularly limited, but specific examples thereof include Ziegler catalysts composed of a transition metal compound and alkylaluminum or alkyllithium; metallocene catalysts.
Specific examples of transition metal compounds used in Ziegler-based catalysts include nickel salts such as nickel acetate, nickel octylate and nickel acetylacetonate; cobalt salts such as cobalt acetate, cobalt octylate and cobalt acetylacetonate; titanocene dichloride and zirconocene. dichlorides.
Specific examples of alkylaluminums used in Ziegler catalysts include trimethylaluminum, triethylaluminum, triisobutylaluminum, and trioctylaluminum.
Specific examples of alkyllithium used in Ziegler catalysts include methyllithium, ethyllithium, n-butyllithium, sec-butyllithium and t-butyllithium.
These homogeneous catalysts may be used singly or in combination of two or more. Moreover, the homogeneous catalyst may be used in combination with the heterogeneous catalyst.

In the hydrogenation reaction of step (C), since the polymer is hydrogenated, the reaction activity for low-molecular-weight compounds is generally low. Therefore, in many cases, relatively high temperature and high pressure conditions are preferable as the reaction conditions, and it is preferable to use a heterogeneous catalyst with high thermal stability. From the aspect of hydrogenation activity, it is preferable to use nickel or palladium as the metal having hydrogenation activity. Moreover, in order to suppress undesirable side reactions during the hydrogenation reaction, it is preferable to use calcium carbonate or a carbon support as the support, and it is more preferable to use a carbon support.

The hydrogenation reaction is usually carried out in an organic solvent. Such an organic solvent is not particularly limited, and for example, the solvents exemplified in the above step (B) or step (E) described later can be used.

The above hydrogenation reaction may be carried out, for example, in a state in which the unhydrogenated conjugated diene-based graft polymer is present in the solvent used in the above step (B), without particularly treating the organic solvent. Alternatively, after part of the solvent is removed by a method such as distillation, the reaction may be carried out in the remaining solvent, or after dilution with an organic solvent, the reaction may be carried out in the solvent. After the step (B) is completed, the unhydrogenated conjugated diene-based graft polymer is temporarily taken out, and the unhydrogenated conjugated diene-based graft polymer is put into an organic solvent to carry out a hydrogenation reaction in the solvent. may

When the hydrogenation reaction is carried out in an organic solvent, the amount of the organic solvent used should be such that the concentration of the unhydrogenated conjugated diene-based graft polymer in the reaction solution is 1% by mass or more and 30% by mass or less. is preferred. If the concentration is less than 1% by mass, the productivity may be significantly reduced, and if it exceeds 30% by mass, the viscosity may be significantly increased and the mixing efficiency may be reduced.

The reaction pressure of the hydrogenation reaction may be appropriately set according to the catalyst used, etc., but the total pressure is usually 0.1 MPa to 20 MPa, preferably 0.5 MPa to 15 MPa, more preferably 0.5 MPa to 5 MPa. be.

The hydrogenation reaction is carried out in the presence of hydrogen gas, but it may be carried out in the presence of a gas mixed with a gas other than hydrogen gas that is inert to the hydrogenation reaction. Specific examples of gases inert to the hydrogenation reaction include nitrogen, helium, argon, and carbon dioxide. Also, depending on the reaction conditions, the solvent used in the reaction may have a significant partial pressure as a gas component, but such a situation is usually not a problem as long as the hydrogenation reaction proceeds.

The reaction temperature for the hydrogenation reaction may be appropriately set according to the catalyst used, but is usually 20°C to 250°C, preferably 50°C to 180°C, more preferably 70°C to 180°C. In general, it may be desirable for heterogeneous catalysts to react at higher temperatures than homogeneous catalysts.
The reaction time for the hydrogenation reaction may be appropriately set according to the type of catalyst used, the amount of catalyst and the reaction temperature, and is usually 0.1 to 100 hours, preferably 1 to 50 hours. If the reaction time is too short, the desired hydrogenation rate may not be obtained. On the other hand, if the reaction time is too long, undesired side reactions may proceed remarkably, and a hydrogenated conjugated diene-based graft polymer having desired physical properties may not be obtained.

The reaction form of the hydrogenation reaction is not particularly limited, and may be appropriately set according to the type of catalyst used in the reaction. Examples of the reaction format include a batch reaction format, a semi-continuous reaction format (semi-batch reaction format), and a continuous reaction format. Suitable continuous reaction formats include plug flow format (PFR), continuous flow stirred format (CSTR), and the like.
When using a heterogeneous catalyst, the hydrogenation reaction can be carried out using a fixed bed reactor.
When the hydrogenation reaction is carried out under positive mixing conditions, the mixing method includes a mixing method by stirring and a mixing method in which the reaction solution is circulated in a loop.
When a heterogeneous catalyst is used under mixed conditions, the reaction is by a suspended bed and becomes a gas-liquid-solid reaction field. Further, when a homogeneous catalyst is used under mixed conditions, the reaction field becomes a gas-liquid two-phase system.
Hydrogen in a reaction format in which the hydrogenation reaction in the reaction vessel is once terminated, the reaction liquid is withdrawn, and at least part of the withdrawn reaction liquid is charged into the same or different reaction vessel to further perform the hydrogenation reaction. An addition reaction may be performed. By carrying out the hydrogenation reaction in such a reaction format, if it is possible to avoid localization of the heat generation accompanying the hydrogenation reaction, the hydrogenation rate may be improved.
The hydrogenation reaction may be carried out in a single reaction format, or in combination of two or more reaction formats that are the same or different.
When aiming for a higher hydrogenation rate, it may be desirable to use a fixed-bed reactor and use a hydrogenation reaction step that includes a plug-flow reaction step.

The amount of catalyst used in the hydrogenation reaction may be appropriately set according to the type of catalyst used, the concentration of the unhydrogenated conjugated diene-based graft polymer, and the reaction mode. When carrying out a hydrogenation reaction, the amount of the catalyst used per 100 parts by mass of the reaction liquid containing the unhydrogenated conjugated diene graft polymer is usually 0.01 to 20 parts by mass, preferably 0.05 to 15 parts by mass, More preferably, it is 0.1 to 10 parts by mass. If the amount of catalyst used is too small, the hydrogenation reaction may require a long time, and if the amount of catalyst used is too large, more power may be required to mix the heterogeneous catalyst. In addition, when the hydrogenation reaction is carried out in a fixed bed, it is difficult to specify the amount of catalyst used per reaction liquid containing the unhydrogenated conjugated diene graft polymer. You can set it.
Ziegler catalyst as a homogeneous catalyst; when using a metallocene catalyst, the concentration in the reaction solution containing the unhydrogenated conjugated diene graft polymer of the transition metal compound is usually 0.001 mmol/liter to 100 mmol/liter. , preferably 0.01 mmol/liter to 10 mmol/liter.

The catalyst used in the hydrogenation reaction may be separated from the liquid containing the hydrogenated conjugated diene-based graft polymer, if necessary, after the completion of the hydrogenation reaction. The separation method is not particularly limited as long as the catalyst can be separated. If a heterogeneous catalyst is used, the catalyst can be separated by, for example, continuous or batch filtration, centrifugation, settling by settling and decantation. When a homogeneous catalyst is used, the catalyst can be separated by, for example, coagulation sedimentation, adsorption, washing and aqueous phase extraction.
Even if the used catalyst is separated by these separation methods, trace amounts of metal components derived from the catalyst may remain in the liquid containing the hydrogenated conjugated diene graft polymer. Also in this case, since the metal component remains in the liquid, the remaining metal component can be separated by a separation method such as coagulation sedimentation, adsorption, washing, and aqueous phase extraction, as described above.
The catalyst recovered by separation can be used again for the hydrogenation reaction after removing part of it or adding a new catalyst, if necessary.

[Step (D)]
A method for producing a hydrogenated conjugated diene-based graft polymer by the MI method,
(D) a step of recovering the obtained hydrogenated conjugated diene-based graft polymer;
including.

In step (D), the obtained hydrogenated conjugated diene-based graft polymer of the present invention is recovered. The method for recovering the hydrogenated conjugated diene-based graft polymer is not particularly limited. A solution containing a conjugated diene-based graft polymer is poured into a poor solvent such as methanol to precipitate a hydrogenated conjugated diene-based graft polymer, or a polymerization reaction solution is poured into hot water together with steam to azeotrop the solvent. (steam stripping) and then dried, or the hydrogenated conjugated diene-based graft polymer can be recovered by isolating the above-mentioned hydrogenated conjugated diene-based graft polymer by washing the polymerization reaction solution with water, separating it, and drying it. In addition, when the hydrogenated conjugated diene graft polymer is already obtained as a solution containing the hydrogenated conjugated diene graft polymer before performing the step (D), the solution is concentrated as it is or the solution is concentrated. Alternatively, after diluting, step (D) may be performed by the method as described above.

An antioxidant may be added to the conjugated diene-based graft polymer of the present invention in any of the steps described above, if necessary. For example, it may be added after step (B), after step (C) or at each step during step (D), or after step (D) or at each step during step (D).
Preferred anti-aging agents used at this time include, for example, 2,6-di-t-butyl-4-methylphenol (BHT), 2,2'-methylenebis(4-methyl-6-t-butylphenol), 4,4 '-thiobis(3-methyl-6-t-butylphenol), 4,4'-butylidenebis(3-methyl-6-t-butylphenol) (AO-40), 3,9-bis[1,1-dimethyl- 2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane (AO-80), 2,4-bis[(octylthio)methyl]-6-methylphenol (Irganox 1520L), 2,4-bis[(dodecylthio)methyl]-6-methylphenol (Irganox 1726), 2-[1-(2-hydroxy- 3,5-di-t-pentylphenyl)ethyl]-4,6-di-t-pentylphenyl acrylate (SumilizerGS), 2-t-butyl-6-(3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate (Sumilizer GM), 6-t-butyl-4-[3-(2,4,8,10-tetra-t-butyldibenzo[d,f][1,3,2]dioxa Phosphepin-6-yloxy)propyl]-2-methylphenol (SumilizerGP), Tris(2,4-di-t-butylphenyl)phosphite (Irgafos168), Dioctadecyl 3,3'-dithiobispropionate , hydroquinone, p-methoxyphenol, N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (Nocrac 6C), bis(2,2,6,6-tetramethyl-4-piperidyl) Sebacate (LA-77Y), N,N-dioctadecylhydroxylamine (IrgastabFS042), bis(4-t-octylphenyl)amine (Irganox5057) and the like. The anti-aging agents may be used singly or in combination of two or more.

<Coupling method (CP method)>
As a method for producing the hydrogenated conjugated diene-based graft polymer of the present invention, a production method by a coupling method (CP method) including the following steps (E), (C) and (D) is a preferred embodiment. .

(E) a functional group-modified conjugated diene-based polymer having an active terminal polymer represented by the following formula (I) and an epoxy group (hereinafter, this polymer is also referred to as a functional group-modified conjugated diene-based polymer (F) ) to prepare a conjugated diene-based graft polymer

PX (I)
(In formula (I), P represents a polymer chain containing at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit, and X represents an anionic polymerization active terminal. ); and (C) hydrogenating at least part of the carbon-carbon double bonds contained in the conjugated diene units contained in the conjugated diene graft polymer to form a hydrogenated conjugated diene graft polymer; and (D) a step of recovering the obtained hydrogenated conjugated diene-based graft polymer

[Step (E)]
The active terminal polymer (I) used in the above step (E) can be produced using a known polymerization method. For example, in a solvent inert to the polymerization terminal, using an anionically polymerizable active metal or active metal compound as an initiator, optionally in the presence of a polar compound, by anionically polymerizing a monomer, the active terminal is polymerized. Coalescence (I) can be obtained. The P of this active terminal polymer (I) becomes the side chain (b) of the hydrogenated conjugated diene graft polymer obtained in the present invention.

Description of specific examples of monomers to be monomer units constituting the active terminal polymer (I), preferred embodiments, etc., and specific examples and preferred embodiments of the monomer units contained in the active terminal polymer (I) is the same as the side chain (b) of the hydrogenated conjugated diene graft polymer.

As the anionically polymerizable active metal or active metal compound, an organic alkali metal compound is preferred, and an organic lithium compound is more preferred. Examples of the organic lithium compound include methyllithium, ethyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, and pentyllithium.

Examples of the solvent include aliphatic hydrocarbons such as n-butane, n-pentane, isopentane, n-hexane, n-heptane and isooctane; alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclopentane; and benzene. , toluene, and xylene; and ether compounds such as dibutyl ether, tetrahydrofuran, and ethylene glycol diethyl ether.

A polar compound may be added during the anionic polymerization. Polar compounds are commonly used in anionic polymerizations to control the microstructure (vinyl content) of the conjugated diene units without quenching the reaction. Examples of polar compounds include ether compounds such as dibutyl ether, tetrahydrofuran and ethylene glycol diethyl ether; tertiary amines such as tetramethylethylenediamine and trimethylamine; alkali metal alkoxides and phosphine compounds. The polar compound is generally used in an amount of 0.01 to 1000 mol per 1 mol of the organic alkali metal compound.

The temperature of the anionic polymerization is usually in the range of -80 to 150°C, preferably in the range of 0 to 100°C, more preferably in the range of 10 to 90°C. The mode of polymerization may be either a batchwise system or a continuous system.

The P of the above active terminal polymer (I) finally becomes the side chain (b) of the hydrogenated conjugated diene-based graft polymer of the present invention. The description of the preferred embodiments of the number average molecular weight (Mn) of P, vinyl content, and Tg of the active terminal polymer (I) relates to the side chain (b) of the hydrogenated conjugated diene-based graft polymer of the present invention. It is the same.

In the above step (E), the functional group-modified conjugated diene-based polymer (F) is obtained, for example, by modifying the unmodified conjugated diene-based polymer (F') with a functional group in the modification step described below. The method for producing the unmodified conjugated diene-based polymer (F′) is not particularly limited, and can be applied in the same manner as the method for producing the polymer (M) containing conjugated diene units described above. The portion of the functional group-modified conjugated diene-based polymer (F) other than the functional group-modified conjugated diene-based polymer becomes the main chain (a) of the hydrogenated conjugated diene-based graft polymer of the present invention.

Specific examples and preferred examples of the conjugated diene, which is a monomer unit constituting the unmodified conjugated diene-based polymer (F'), preferred content thereof, and other monomers other than the conjugated diene (aromatic vinyl compound, etc.) are the same as those for the main chain (a) of the hydrogenated conjugated diene-based graft polymer. In addition, the description of the number average molecular weight (Mn), vinyl content, preferred aspects of Tg, etc. of the unmodified conjugated diene-based polymer (F′) is the description of the main chain (a) of the hydrogenated conjugated diene-based graft polymer. It is the same. When the functional group-modified conjugated diene-based polymer (F) to be the main chain (a) is produced by the CP method, 4-methylstyrene units are included as aromatic vinyl compound units contained in the polymer. good too. This is because the side chain (b) is not bound to the aromatic group contained in the 4-methylstyrene unit when the conjugated diene-based graft polymer is produced by the CP method.

The method for producing the functional group-modified conjugated diene polymer (F) having an epoxy group by modifying the unmodified conjugated diene polymer (F') with a functional group is not particularly limited, and conventionally known methods can be used. It can be according to the method. For example, by epoxidizing the unmodified conjugated diene-based polymer (F′) using an epoxidizing agent such as hydroperoxides and organic peracids, a functional group-modified conjugated diene-based polymer (F ) can be manufactured. Hydroperoxides include hydrogen peroxide, t-butyl hydroperoxide, cumene hydroperoxide and the like. Examples of organic peracids include performic acid, peracetic acid, perbenzoic acid, trifluoroperacetic acid, m-chloroperbenzoic acid and the like. The organic peracid may be an equilibrium peracid using hydrogen peroxide and an organic acid.

If necessary, a catalyst may be used in the epoxidation reaction. Combinations of the epoxidizing agent and the catalyst include, for example, when the epoxidizing agent is a hydroperoxide, a combination of hydrogen peroxide and a mixture of tungstic acid and caustic soda, a combination of hydrogen peroxide and an organic acid, t- Examples include a combination of butyl hydroperoxide and molybdenum hexacarbonyl. Further, when the epoxidizing agent is an organic peracid, a combination of an organic peracid and an alkali such as sodium carbonate or an acid such as sulfuric acid may be used.
Other epoxidation reactions include phase-transfer heteropolyacids prepared from heteropolyacids containing tungsten or molybdenum (especially 12-tungstophosphoric acid) and surfactants (especially halogenated quaternary ammonium salts). A method of epoxidation with hydrogen peroxide in a two-phase system of an aqueous phase and an organic phase in the presence of an acid is also included.
The amount of the epoxidizing agent and the catalyst used is not particularly limited, and can be appropriately set according to the type of polymer to be epoxidized, the type of epoxidizing agent, the degree of epoxidation of the polymer to be epoxidized, and the like. .

The epoxidation reaction can be carried out in the absence of a solvent, but it may also be carried out in the presence of a solvent that is inert to the epoxidizing agent. Solvents that can be used for the epoxidation reaction include aliphatic hydrocarbons such as hexane and heptane, esters such as ethyl acetate, aromatic hydrocarbons such as benzene and xylene, and halogenated hydrocarbons such as chloroform and carbon tetrachloride. Hydrogen is mentioned.

The reaction temperature of the above epoxidation reaction is usually in the range of 0 to 140°C, preferably 0 to 80°C, more preferably 10 to 40°C, from the viewpoints of reaction rate, reaction selectivity, safety, and the like. If the reaction temperature is too low, the reaction rate tends to decrease. From the viewpoint of safety, the reaction is preferably carried out under an inert gas atmosphere such as nitrogen or argon. The reaction time can be appropriately set according to the desired epoxidation rate, and is, for example, 1 to 48 hours, preferably 4 to 36 hours, more preferably 8 to 36 hours.

The average number of epoxy groups per molecule of the functional group-modified conjugated diene polymer (F) is preferably 2 to 150, more preferably 3 to 90, and even more preferably 4 to 70.

The average number of epoxy groups per molecule of the functional group-modified conjugated diene polymer (F) is determined by the epoxy equivalent (g/eq) contained in the functional group-modified conjugated diene polymer (F) and the functional group-modified conjugated diene system. It is obtained from the following formula (4) using the number average molecular weight (Mn) of the polymer (F) in terms of standard polystyrene.
(Average number of epoxy groups per molecule of functional group-modified conjugated diene polymer (F)) = [(number average molecular weight Mn of functional group-modified conjugated diene polymer (F))/(molecular weight of styrene unit) × (Average molecular weight of conjugated diene units contained in functional group-modified conjugated diene-based polymer (F) and optionally other monomeric units other than conjugated dienes)]/(epoxy equivalent) (4)

The epoxy equivalent of the epoxy group contained in the functional group-modified conjugated diene-based polymer (F) is the conjugated diene bonded per epoxy group and other monomers other than the conjugated diene optionally contained. means body mass. The epoxy equivalent is calculated from the area ratio of the peak derived from the epoxy group and the peak derived from the main chain of the polymer using ¹ H-NMR.

The description of the number average molecular weight (Mn), vinyl content, preferred aspects of Tg, etc. of the functional group-modified conjugated diene-based polymer (F) is the same as that of the unmodified conjugated diene-based polymer (F').

The melt viscosity of the functional group-modified conjugated diene polymer (F) measured at 38° C. is preferably 0.01 to 2,000 Pa s, more preferably 0.05 to 1500 Pa s, and 0.1 to 1000 Pa. • s is more preferred. When the melt viscosity of the functional group-modified conjugated diene-based polymer (F) is within the above range, it tends to be excellent in the ability to pass the process during production and to be economically efficient.

In step (E), by reacting the active terminal polymer (I) with the functional group-modified conjugated diene polymer (F), the epoxy groups in the functional group-modified conjugated diene polymer (F) and the active The terminal polymer (I) reacts to form a conjugated diene-based graft polymer in which the active terminal polymer (I) as a side chain is bound to the main chain (a) (hereinafter, this reaction is referred to as a coupling reaction (referred to as
An example of the coupling reaction when epoxy-modified polybutadiene is used as the functional group-modified conjugated diene polymer (F) is shown in the following formula (II).

(In formula (II), P represents a polymer chain containing at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units.)

In the coupling reaction or the step of hydrogenation or washing described later, the ring-opening of the epoxy group in the functional group-modified conjugated diene polymer (F) results in the main chain of the hydrogenated conjugated diene graft polymer ( A hydroxyl group is formed that bonds to a). When a hydroxyl group is formed by this synthesis method, the hydroxyl group is directly bonded to atoms (typically carbon atoms) constituting the main chain (a) other than the atoms bonded to the side chain (b).

The average number of epoxy groups per molecule of the functional group-modified conjugated diene polymer (F) can be appropriately set according to the average number of hydroxyl groups bonded to the main chain (a) described above. For example, when the average number of epoxy groups per molecule of the functional group-modified conjugated diene polymer (F) is 4, hydroxyl groups bonded to the main chain (a) per molecule of the finally obtained conjugated diene graft polymer can be designed to have an average number of four.

The average number of side chains (b) per molecule of the hydrogenated conjugated diene-based graft polymer is the amount of charged active terminal polymer (I) and functional group-modified conjugated diene-based polymer (F) in the above coupling reaction. The ratio can be adjusted to the desired range. For example, (amount (number of moles) charged of active terminal polymer (I))/(amount (number of moles) charged of functional group-modified conjugated diene polymer (F)) = 4/1, the side chain (b ) is 4 on average. However, the upper limit of the average number of side chains (b) is the number of epoxy groups per molecule of the functional group-modified conjugated diene polymer (F).

The molar ratio of (charged amount of active terminal polymer (I))/(charged amount of functional group-modified conjugated diene polymer (F)) is the side chain per molecule of hydrogenated conjugated diene graft polymer (b ) may be appropriately set so as to obtain a desired value. If the molar ratio of (charged amount of active terminal polymer (I))/(charged amount of functional group-modified conjugated diene-based polymer (F)) is less than 2, the number of side chains that can be introduced is less than 200. If it is too large, the coupling rate, which will be described later, tends to decrease.

The above coupling reaction is usually carried out at a temperature of 0 to 100° C. for 0.5 to 50 hours. The functional group-modified conjugated diene-based polymer (F) may be diluted before use, and the solvent for dilution is not particularly limited as long as it is inert to the active terminal and does not adversely affect the reaction. Examples include hexane and cyclohexane. , heptane, octane, decane, toluene, benzene, xylene and other saturated aliphatic or aromatic hydrocarbons.
Also, a Lewis base may be added as an additive during the coupling reaction. Lewis bases include, for example, ethers such as dimethyl ether, diethyl ether and tetrahydrofuran; glycol ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether; triethylamine, N,N,N',N'-tetramethylethylenediamine, N-methylmorpholine; amines such as These Lewis bases may be used singly or in combination of two or more.

In the coupling reaction, the functional group-modified conjugated diene polymer (F) may be added to the reaction system in which the active terminal polymer (I) was synthesized, or conversely, the functional group-modified conjugated diene The active terminal polymer (I) may be added to the system containing the system polymer (F). Moreover, as described above, both the active terminal polymer (I) and the functional group-modified conjugated diene polymer (F) may be used after being diluted with a solvent, if necessary. The active terminal polymer (I) may be used alone or in combination of two or more. The functional group-modified conjugated diene polymer (F) may also be used alone. may be used in combination of two or more.

The coupling rate in the above coupling reaction is preferably 40% or higher, more preferably 50% or higher, even more preferably 60% or higher. If the coupling rate is less than 40%, the obtained hydrogenated conjugated diene graft polymer will have poor mechanical properties, which is not preferable. The coupling ratio is determined by the following formula (5) using the peak area of the component derived from the unreacted active terminal polymer (I) obtained by GPC measurement and the total sum of all peak areas.
(Coupling rate (%)) = [{(sum of all peak areas) - (peak area of component derived from active terminal polymer (I))}/(sum of all peak areas)] x 100 ( 5)

The coupling rate can be adjusted by increasing the amount of the functional group-modified conjugated diene polymer (F) added to the active terminal polymer (I), by increasing the amount of the Lewis base added to the active terminal polymer (I), or by adjusting the reaction It can be increased by raising the temperature or lengthening the reaction time. The coupling reaction can be carried out until the coupling rate reaches the desired range. After that, the coupling reaction can be stopped by adding a polymerization terminator such as methanol or isopropanol.

A conjugated diene-based graft polymer obtained by a production method including steps (E) and (D) without including step (C), which will be described in detail below, is an unhydrogenated conjugated diene-based graft polymer.

[Step (C)]
In the method for producing a hydrogenated conjugated diene-based graft polymer of the present invention, before step (D),
(C) a step of hydrogenating at least part of the carbon-carbon double bonds contained in the conjugated diene units in the (unhydrogenated) conjugated diene graft polymer to form a hydrogenated conjugated diene graft polymer; ;
including.

A hydrogenated conjugated diene graft polymer can be obtained by subjecting the unhydrogenated conjugated diene graft polymer obtained by the above method to a step of hydrogenating. The method of hydrogenating the unhydrogenated conjugated diene-based graft polymer is not particularly limited, and is the same as the method of hydrogenating the unhydrogenated conjugated diene-based graft polymer described as the step (C) of the MI method described above. method can be applied.

[Step (D)]
The method for producing the hydrogenated conjugated diene-based graft polymer used in the present invention comprises:
(D) a step of recovering the obtained hydrogenated conjugated diene-based graft polymer;
including.

In step (D), the obtained hydrogenated conjugated diene-based graft polymer is recovered. The method for recovering the hydrogenated conjugated diene-based graft polymer is not particularly limited, and the same method as the method for recovering the conjugated diene-based graft polymer described as the step (D) of the MI method described above can be applied.

An antioxidant may be added to the conjugated diene-based graft polymer of the present invention in any of the steps described above, if necessary. For example, it may be added after step (E), after step (C) or at each step during step (D), or after step (D) or at each step during step (D).
Preferred anti-aging agents used at this time are the same anti-aging agents exemplified in the step of the MI method described above.

[Polymer composition]
The polymer composition of the present invention contains the hydrogenated conjugated diene graft polymer of the present invention (hereinafter also referred to as hydrogenated conjugated diene graft polymer (α)). The polymer composition may further contain a polymer (β) other than the hydrogenated conjugated diene graft polymer (α). The other polymer (β) may be a thermoplastic polymer (β1) or a curable polymer (β2).

Examples of the thermoplastic polymer (β1) include acrylic resins such as polymethyl methacrylate and (meth)acrylic acid ester polymers or copolymers; polyethylene, ethylene-vinyl acetate copolymer, polypropylene, polybutene- 1, poly-4-methylpentene-1, olefin resins such as polynorbornene; ethylene ionomer; polystyrene, styrene-maleic anhydride copolymer, high impact polystyrene, AS resin, ABS resin, AES resin, AAS resin, Styrene resins such as ACS resin and MBS resin; Styrene-methyl methacrylate copolymer; Styrene-methyl methacrylate-maleic anhydride copolymer; Polyester resins such as polyethylene terephthalate, polybutylene terephthalate and polylactic acid; Nylon 6, Polyamides such as nylon 66, polyamide elastomer; Polycarbonate; Polyvinyl chloride; Polyvinylidene chloride; Polyvinyl alcohol; Ethylene-vinyl alcohol copolymer; Polyacetal; acrylic rubbers; silicone rubbers; styrene thermoplastic elastomers such as SEPS, SEBS and SIS (excluding the conjugated diene graft polymer of the present invention); olefin rubbers such as IR, EPR and EPDM.

Examples of the curable polymer (β2) include epoxy resins, unsaturated polyester resins, epoxy (meth)acrylate resins, ester (meth)acrylate resins, phenol resins, urea resins, melamine resins, thermosetting urethane resins, silicon Resins, imide resins, furan resins, alkyd resins, allyl resins, diallyl phthalate resins. Among these, from the viewpoint of availability and basic physical properties of the cured product, and from the viewpoint of obtaining a polymer composition that is more excellent due to the ability to remove air bubbles and the toughness of the cured product obtained, epoxy resins, unsaturated polyesters Resins and epoxy (meth)acrylate resins are preferred, among which epoxy resins and unsaturated polyester resins are more preferred, and epoxy resins are even more preferred. The curable polymer (β2) may be used singly or in combination of two or more.

When the polymer composition contains the hydrogenated conjugated diene graft polymer (α) and another polymer (β), the hydrogenated conjugated diene graft polymer (α) and the other polymer (β) The mass ratio (α)/(β) with is preferably 1/99 to 99/1.

Moreover, various additives may be added to the polymer composition of the present invention to the extent that the effects of the present invention are not impaired. For example, when the other polymer (β) is a thermoplastic polymer (β1), such additives include reinforcing agents or fillers such as calcium carbonate, silica, carbon black, glass fiber, clay, process oil, , polyethylene glycol, glycerin, phthalates, and other plasticizers can be used as additives. Other additives include, for example, heat stabilizers, antioxidants, ultraviolet absorbers, colorants, pigments, lubricants, and surfactants. Furthermore, the additive includes a foaming agent, and a foam can be produced from a polymer composition containing the foaming agent and the thermoplastic polymer (β1).
For example, when the other polymer (β) is a curable polymer (β2), such additives include curing agents, curing accelerators, known rubbers, thermoplastic elastomers, impact modifiers such as core-shell particles, etc. agents, fillers (silica, talc, calcium carbonate, inorganic particles such as aluminum hydroxide, etc.), flame retardants, antifoaming agents, pigments, dyes, antioxidants, weathering agents, lubricants, release agents, and the like.

The polymer composition of the present invention can be prepared by a conventional method for mixing polymeric substances depending on the composition ratio of each component such as the hydrogenated conjugated diene graft polymer (α) and the other polymer (β). .

When the other polymer (β) is a thermoplastic polymer (β1), the polymer composition can be produced using a mixing device such as an extruder, mixing roll, Banbury mixer, kneader, or the like. In particular, in the present invention, a method of melt-kneading using these mixing apparatuses is a preferred embodiment.

When the other polymer (β) is a curable polymer (β2), for example, the polymer composition is obtained by thoroughly mixing with a mixer, melt-kneading with a mixing roll, an extruder, or the like, then cooling and pulverizing. can be made.

The polymer composition of the present invention may be a crosslinkable polymer composition containing the hydrogenated conjugated diene graft polymer (α). Such polymer compositions additionally contain a cross-linking agent.
Examples of cross-linking agents include sulfur, sulfur compounds, hydrogen peroxide, peroxides such as organic peroxides, phenolic resins, amino resins, quinones and quinonedioxime derivatives, halogen compounds, aldehyde compounds, alcohol compounds, epoxy compounds, metals. Halides, organometallic halides, silane compounds, and the like.
When sulfur, a sulfur compound, or the like is contained as a cross-linking agent, a vulcanization accelerator or a vulcanization aid may also be contained.
The crosslinkable polymer composition includes solid rubbers such as natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene copolymer rubber (excluding conjugated diene graft polymer (α)), carbon black, Fillers such as silica, cross-linking aids, softeners such as oils, tackifying resins, anti-aging agents, antioxidants, light stabilizers, anti-scorch agents, compounds containing functional groups, waxes, lubricants, plasticizers, processing aids , pigments, pigments, dyes, other coloring agents, flame retardants, antistatic agents, matting agents, antiblocking agents, UV absorbers, release agents, foaming agents, antibacterial agents, antifungal agents, fragrances, dispersants, solvents It may contain additives such as

The polymer composition of the present invention can be molded into articles by various conventionally known molding methods.

When the other polymer (β) is a thermoplastic polymer (β1), the polymer composition is molded by, for example, extrusion molding, injection molding, blow molding, compression molding, vacuum molding, calender molding, etc. products can be produced. Molded articles, sheets, films and the like of various shapes can be obtained by these methods. In addition, non-woven fabrics and fibrous molded articles can also be produced by methods such as melt blowing and spunbonding.

When the other polymer (β) is the curable polymer (β2), a molded article can be produced by thermally curing the polymer composition, for example, by a transfer molding method. Other molding methods when the polymer composition contains the curable polymer (β2) include, for example, injection molding and compression molding.

Further, when the polymer composition of the present invention is a crosslinkable polymer composition, it can be used as a crosslinked product by crosslinking. The cross-linking conditions for the cross-linkable polymer composition can be appropriately set according to the application and the cross-linking agent to be used. For example, when the cross-linking agent is a peroxide, a cross-linked product can be produced by performing a cross-linking reaction at a temperature of 130° C. to 250° C. for 10 minutes to 60 minutes. For example, when the cross-linking agent is sulfur or a sulfur compound, a vulcanization mold can be used at a vulcanization temperature of 120 to 200° C. and a vulcanization pressure of 0.5 to 20 MPa.

When the other polymer (β) is a thermoplastic polymer (β1), the uses of molded articles obtained from the polymer composition include, for example, automobile interior and exterior parts such as bumpers and instrument panels, televisions, stereos, and cleaners. Housing materials for home appliances such as machines, electrical and electronic parts such as connectors, materials for electric cables, meat and fish trays, fruit and vegetable packs, frozen food containers and other food packaging materials or food containers, industrial materials and other packaging materials, sports Sporting goods such as shoe materials, fabric or leather products, toys, sandals and other daily goods, various films, sheets, laminated materials for molded products, adhesives and adhesives, elastic materials used for paper diapers, hoses, tubes, belts and various rubber products, medical supplies, and the like.

When the other polymer (β) is a curable polymer (β2), applications of the polymer composition, its cured product or molded article include, for example, adhesives for fiber-reinforced composite materials (fiber-reinforced composite materials for concrete Adhesives for fiber reinforced composite materials for transportation equipment such as automobiles, railway vehicles and aircraft, adhesives for fiber reinforced composite materials for various sporting goods, etc.), adhesives for assembly (transportation such as automobiles, railway vehicles and aircraft Adhesives for assembling parts in transportation equipment, etc.); various paints such as anti-corrosion and waterproof paints for water supply and sewage, anti-corrosion paints for metals; Various coating primers such as coating primers; Various lining materials such as metal lining materials, concrete lining materials, and tank lining materials; Various repair materials such as concrete crack repair materials; Printed wiring boards, insulating boards, semiconductor sealing Examples include various electric and electronic parts such as sealing materials and packaging materials.

Applications in which the crosslinkable polymer composition and the crosslinked product of the polymer composition can be used include tires, belts, anti-vibration rubber, wire coating rubber, rolls, shoes, sealants, adhesives, greases, Examples include printing plate materials, OCR, OCA, paints, fenders, coating agents, gaskets, hoses, and brake pads.

The above-mentioned crosslinkable polymer composition or crosslinked product of the polymer composition is suitably used, for example, as a part of a tire.
Examples of tire parts where the polymer composition and the crosslinked product of the polymer composition can be used include the tread (cap tread, undertread), sidewall, rubber reinforcing layer for run-flat tires (liner, etc.), and rim. Cushions, bead fillers, bead insulation, bead apex, clinch apex, belts, belt cushions, breakers, breaker cushions, chafers, chafer pads, strip apex and the like.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the following examples and comparative examples, physical properties of hydrogenated conjugated diene-based graft polymers were evaluated by the following methods.

(1) Weight average molecular weight (Mw), number average molecular weight (Mn), molecular weight distribution (Mw/Mn)
By gel permeation chromatography (GPC), the hydrogenated conjugated diene-based graft polymer and the weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw/Mn) of the polymer at each stage of its production ) was calculated in terms of standard polystyrene.
Apparatus: GPC apparatus "HLC-8220" manufactured by Tosoh Corporation
Separation column: Tosoh Corporation "TSKgel SuperMultiporeHZ-M (column diameter = 4.6 mm, column length = 15 cm)" (used by connecting two in series)
Eluent: Tetrahydrofuran Eluent flow rate: 0.35 mL/min Column temperature: 40°C
Detection method: Differential refractive index (RI)
Injection volume: 10 μl
Concentration: 1 mg/1 cc (hydrogenated conjugated diene-based graft polymer/THF)

(2) Vinyl content, styrene unit (structural unit derived from styrene) content, hydrogenation rate ¹ H-NMR, conjugated diene graft polymer, vinyl content of polymer at each stage of its production, and styrene A unit content and a hydrogenation rate were calculated. The vinyl content was calculated from the area ratio of the peak of the double bond of the vinylated conjugated diene unit in the obtained spectrum and the peak of the double bond derived from the non-vinylated conjugated diene unit, and the vinyl content was derived from the styrene unit. The styrene unit content was calculated from the area ratio of the peak of the aromatic ring and the peak of the double bond derived from the conjugated diene unit. The vinyl content and styrene unit content were obtained by using ¹ H-NMR of the conjugated diene graft polymer before hydrogenation. The hydrogenation rate was calculated from the peak ratio of the double bond derived from the conjugated diene unit of the conjugated diene graft polymer before hydrogenation and the hydrogenated conjugated diene graft polymer after hydrogenation.
Apparatus: Nuclear magnetic resonance apparatus "JNM-ECX400" manufactured by JEOL Ltd.
Solvent: Heavy chloroform Measurement temperature: 50°C
Accumulated times: 1024 times

(3) Average number of side chains (b) per molecule of hydrogenated conjugated diene graft polymer When the conjugated diene polymer is reacted with an organic alkali metal compound in the presence of tetramethylethylenediamine to lithiate the main chain and then polymerize the monomers that form the structural units of the side chains, It was calculated from the feed ratio of the organic alkali metal used in the lithiation reaction, the conjugated diene polymer as the structural unit of the main chain, and the functionalizing agent added as necessary. In addition, the active terminal of the polymer obtained by polymerizing the epoxy group contained in the monomer unit that will be the branch portion of the functional group-modified polymer that will be the main chain (a) described later and the monomer that will be the structural unit of the side chain In the case of production by a method of reacting with , it was calculated from the charging ratio of the active terminal polymer and the functional group-modified conjugated diene polymer, which are the constituents of the side chain (b) in the coupling reaction.

(4) Side chain density of side chain (b) It was calculated from the following formula (1) using the number average molecular weight (Mn) in terms of standard polystyrene.
(Side chain density) = (average number of side chains (b) per molecule of hydrogenated conjugated diene graft polymer)/[(number average molecular weight Mn of main chain (a))/(molecular weight of styrene unit)] ×100 (1)

(5) Average number of hydroxyl groups bonded to main chain (a) per molecule of hydrogenated conjugated diene graft polymer Average number of hydroxyl groups bonded to main chain (a) per molecule of hydrogenated conjugated diene graft polymer As described above, the number is the hydroxyl value (mgKOH/g) of the hydrogenated conjugated diene graft polymer calculated according to JIS K1557-1: 2007 and the number of standard polystyrene equivalents of the hydrogenated conjugated diene graft polymer. Obtained from the following formula (2) using the average molecular weight (Mn).
(Average number of hydroxyl groups bonded to the main chain (a) per molecule of the hydrogenated conjugated diene graft polymer) = {(hydroxyl value of the hydrogenated conjugated diene graft polymer) / [(molecular weight of potassium hydroxide) × 1000]} × (number average molecular weight Mn of hydrogenated conjugated diene graft polymer) × [(average molecular weight of monomer units contained in hydrogenated conjugated diene graft polymer)/(molecular weight of styrene unit) ] (2)

(6) Concentration of hydroxyl groups The concentration of hydroxyl groups bonded to the main chain (a) is determined by the average number of hydroxyl groups bonded to the main chain (a) per molecule of the hydrogenated conjugated diene graft polymer and the standard polystyrene of the main chain (a). Calculated from the following formula (3) using the converted number average molecular weight (Mn).
(Hydroxy group concentration) = (average number of hydroxyl groups bonded to main chain (a) per molecule of hydrogenated conjugated diene graft polymer)/[(number average molecular weight of main chain (a) Mn)/(number of styrene units molecular weight)] × 100 (3)

(7) Affinity with polar materials The affinity of the hydrogenated conjugated diene-based graft polymer with polar materials was evaluated by the separability of a mixed liquid of toluene/water. A hydrogenated conjugated diene-based graft polymer was dissolved in toluene so that the solid content concentration was 10% by mass, and a toluene solution of the polymer and water were mixed at a weight ratio of 1:1 and shaken at room temperature for 5 minutes. It was allowed to stand, and the affinity with the polar material was evaluated according to the following indices.
A: It takes 1 minute or more for the organic phase and the aqueous phase to separate, or an intermediate phase in which the organic phase and the aqueous phase are mixed exists at a volume ratio of 10% or more. B: The organic phase and the aqueous phase separate in less than 1 minute. do

(8) Heat resistance The heat resistance of the hydrogenated conjugated diene-based graft polymer was evaluated by the gel fraction after heating. After heating the hydrogenated conjugated diene-based graft polymer at 150° C. for 12 hours in the air, 20 times the amount of cyclohexane was added and the mixture was shaken at room temperature for 12 hours. The mass of the charged polymer was M1, and the mass of the insoluble matter after filtration and drying was M2.
(Gel fraction (%)) = (M2/M1) x 100
A: Gel fraction after drying is less than 50% by mass B: Gel fraction after drying is 50% by mass or more

[Example 1]
(Step (1))
A sufficiently dried 5 L autoclave was purged with nitrogen, charged with 1130 g of cyclohexane, 519 g of sec-butyllithium (10.5% by mass cyclohexane solution) and 15 g of tetrahydrofuran, heated to 50° C. and then heated to 50° C. under stirring conditions. 1,350 g of butadiene was added successively while controlling the temperature to be 0° C., and polymerization was carried out for 1 hour. After that, 31 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution. Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. The unmodified conjugated diene polymer (F'-1) was obtained by vacuum-drying the polymer solution after washing at 70° C. for 24 hours.

(Step (2))
Subsequently, 200 g of the unmodified conjugated diene polymer (F'-1) obtained in step (1), 3800 g of chloroform, 12-tungstophosphate hydrate (H ₃ PW ₁₂ 60 g of O ₄₀ .30H ₂ O), 60 g of hexadecylpyridinium chloride and 400 g of 35% by weight hydrogen peroxide were charged and stirred at room temperature for 15 hours under nitrogen atmosphere. After the reaction, water was added and stirred, the aqueous phase was removed, and the mixture was washed with a 10% by weight aqueous solution of sodium hydrogen sulfite. Silica gel (manufactured by Wako Pure Chemical Industries, Ltd., trade name “C-200”) was added to the separated organic phase, stirred for 1 hour, and then filtered. The filtrate was vacuum-dried at 70° C. for 24 hours to obtain a functional group-modified conjugated diene polymer (F-1). By analyzing the obtained functional group-modified conjugated diene polymer (F-1), the number average molecular weight and vinyl content of the main chain (a) of the hydrogenated conjugated diene graft polymer (G-1) described later are determined. be able to. The resulting functional group-modified conjugated diene polymer (F-1) had a number average molecular weight of 3,000, a vinyl content of 50 mol%, and an epoxy per molecule of the functional group-modified conjugated diene polymer (F-1). The average number of groups was ten. 720 g of toluene was added to 180 g of the obtained functional group-modified conjugated diene polymer (F-1) to dilute it to a concentration of 20% by mass, and the functional group-modified conjugated diene polymer (F-1) used in the coupling reaction described later was obtained. A diluted solution of 1) was obtained.

(Step (3))
A sufficiently dried 5 L autoclave is purged with nitrogen, charged with 2230 g of toluene and 75 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. While controlling as above, 580 g of isoprene was successively added and polymerized for 1 hour to obtain an active terminal polymer (I-1). By sampling and analyzing the polymer solution in step (3), the number average molecular weight, vinyl content, and styrene unit content of the side chain (b) of the hydrogenated conjugated diene graft polymer (G-1) described later. can be asked for. The obtained active terminal polymer (I-1) had a number average molecular weight of 7,000, a vinyl content of 10 mol % and a styrene unit content of 0 mass %.

(Step (4))
Subsequently, 120 g of a diluted solution of the functional group-modified conjugated diene polymer (F-1) obtained in step (2) is added to the solution containing the active terminal polymer (I-1) obtained in step (3). and the coupling reaction was carried out at 50° C. for 2 hours. After that, 8.2 g of methanol was added to terminate the reaction to obtain a polymer solution.

(Step (5))
450 mL of a Ziegler hydrogenation catalyst (0.095 mmol/L cyclohexane solution) formed from nickel octylate and trimethylaluminum was added to the resulting polymer solution, and the reaction was allowed to proceed for 10 hours under conditions of a hydrogen pressure of 1 MPa and 80°C. to obtain a solution containing the hydrogenated conjugated diene graft polymer (G-1).

(Step (6))
Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to recover a hydrogenated conjugated diene-based graft polymer (G-1). The resulting hydrogenated conjugated diene-based graft polymer (G-1) had a weight average molecular weight of 59,000, an Mw/Mn of 1.5, a structural unit content derived from styrene of 0% by mass, and a hydrogenation rate of 85 mol%, the average number of hydroxyl groups bonded to the main chain per polymer molecule is 10, the hydroxyl group concentration is 34.7 mol%, the average number of side chains (b) per polymer molecule is 8, The side chain density was 27.8 mol%. Moreover, the monomer unit that becomes the branched portion has no heteroatom, and the linking portion that bonds to the side chain (b) is not an aromatic group derived from an aromatic vinyl compound. Table 3 shows the molecular specifications and physical properties of the obtained hydrogenated conjugated diene graft polymer (G-1).

[Example 2]
A hydrogenated conjugated diene-based graft polymer (G -2) was obtained. Table 3 shows the molecular specifications and physical properties of the obtained hydrogenated conjugated diene graft polymer (G-2).

[Example 3]
(Step (1))
A sufficiently dried 5 L autoclave is purged with nitrogen, charged with 1470 g of cyclohexane and 177 g of sec-butyllithium (10.5% by mass cyclohexane solution), heated to 50°C, and then brought to a polymerization temperature of 50°C under stirring conditions. While controlling as above, 1350 g of isoprene was added successively and polymerized for 1 hour. After that, 10 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution. Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to obtain a conjugated diene polymer (M-1). Analysis of the obtained conjugated diene-based polymer (M-1) can determine the number average molecular weight and vinyl content of the main chain (a) of the hydrogenated conjugated diene-based graft polymer (G-3) described later. . The resulting conjugated diene polymer (M-1) had a number average molecular weight of 7,000 and a vinyl content of 10 mol %.

(Step (2))
Subsequently, 111 g of the conjugated diene polymer (M-1) obtained in step (1) was charged into a sufficiently dried 5 L autoclave, and the polymer was degassed with nitrogen while stirring at 60° C. for 3 hours. And the inside of the autoclave was replaced with nitrogen. After charging 1230 g of cyclohexane and raising the temperature to 40° C., 87 g of sec-butyllithium (10.5% by mass cyclohexane solution) and 9.2 g of N,N,N',N'-tetramethylethylenediamine were sequentially added, The lithiation reaction was carried out at 40°C for 1 hour.

(Step (3))
Subsequently, 1370 g of cyclohexane was added to dilute the reaction solution, and the temperature was raised to 40° C. again. Then, 9.3 g of 2-ethylhexylaldehyde was added and stirred at 40° C. for 1 hour to functionalize some of the lithiated anion active sites.

(Step (4))
While controlling the polymerization temperature to 40° C., 190 g of butadiene was successively added and polymerized for 2 hours. After that, 7.0 g of methanol was added to terminate the polymerization reaction to obtain a polymer solution. By analyzing the amount of the reagent charged in step (3) and the polymer solution in step (3), the number average molecular weight of the side chain (b) of the hydrogenated conjugated diene graft polymer (G-3) described later, vinyl content and styrene unit content can be determined. The side chain (b) of the hydrogenated conjugated diene graft polymer (G-3) had a number average molecular weight of 5,000, a vinyl content of 75 mol %, and a styrene unit content of 0 mass %.

(Step (5))
450 mL of a Ziegler hydrogenation catalyst (0.095 mmol/L cyclohexane solution) formed from nickel octylate and trimethylaluminum was added to the resulting polymer solution, and the reaction was allowed to proceed for 10 hours under conditions of a hydrogen pressure of 1 MPa and 80°C. to obtain a solution containing a hydrogenated conjugated diene-based graft polymer (G-3).

(Step (6))
Water was added to the obtained polymer solution and stirred, and the polymer solution was washed with water. After finishing the stirring and confirming that the polymer solution phase and the water phase were separated, the water was separated. After washing, the polymer solution was vacuum-dried at 70° C. for 24 hours to recover a hydrogenated conjugated diene-based graft polymer (G-3). The obtained hydrogenated conjugated diene graft polymer (G-3) had a weight average molecular weight of 22,000, an Mw/Mn of 1.5, a structural unit content derived from styrene of 0% by mass, and a hydrogenation rate of 85 mol%, the average number of hydroxyl groups bonded to the main chain per polymer molecule is 3, the hydroxyl group concentration is 4.5 mol%, the average number of side chains (b) per polymer molecule is 3, The side chain density was 4.5 mol%. In addition, the atom bonded to the side chain (b) contained in the monomer unit that becomes the branched portion is not a hetero atom, and the linking portion containing the atom bonded to the side chain (b) is an aromatic vinyl compound-derived aromatic not a tribe. Table 3 shows the molecular specifications and physical properties of the obtained hydrogenated conjugated diene graft polymer (G-3).

[Examples 4-6]
A conjugated diene-based graft polymer (G-4 ), (G-11) and (G-12) were obtained. In Examples 5 and 6, TMEDA (polar compound) used in step (1) was added immediately before adding butadiene after charging cyclohexane and sec-butyllithium into a 5 L autoclave. Table 3 shows the molecular specifications and physical properties of the obtained hydrogenated conjugated diene graft polymers (G-4), (G-11) and (G-12).

[Comparative Examples 1 and 2]
By the same method as in Example 1 except that the type and amount of each reagent used in steps (1) to (4) are changed as shown in Table 1 and the hydrogenation reaction in step (5) is not performed. , (unhydrogenated) conjugated diene-based graft polymers (G-5) and (G-6) were obtained. Table 3 shows the molecular specifications and physical properties of the obtained (unhydrogenated) conjugated diene graft polymers (G-5) and (G-6).

[Comparative Examples 3 and 4]
By the same method as in Example 3 except that the type and amount of each reagent used in steps (1) to (4) are changed as shown in Table 2 and the hydrogenation reaction in step (5) is not performed. , (unhydrogenated) conjugated diene-based graft polymers (G-7) and (G-8) were obtained. Table 3 shows the molecular specifications and physical properties of the obtained (unhydrogenated) conjugated diene-based graft polymers (G-7) and (G-8).

[Comparative Examples 5-7]
Change the type and amount of each reagent used in steps (1), (2), (4), and (5) as described in Table 2, and do not perform the functionalization reaction of step (3). Hydrogenated conjugated diene-based graft polymers (G-9), (G-10), and (G-13) having no hydroxyl group bonded to the main chain were obtained in the same manner as in Example 3, except for the above. In Comparative Example 7, TMEDA (polar compound) used in step (1) was added immediately before adding butadiene after charging cyclohexane and sec-butyllithium into a 5 L autoclave. Table 3 shows the molecular specifications and physical properties of the obtained hydrogenated conjugated diene graft polymers (G-9), (G-10) and (G-13).

The types and amounts of each reagent used in steps (1) to (5) in Examples 1 to 6 and Comparative Examples 1 to 7 are shown in Tables 1 and 2 below, Examples 1 to 6, and Comparative Example 1. Table 3 shows the molecular specifications and physical properties of the polymers (hydrogenated conjugated diene graft polymer, non-hydrogenated conjugated diene graft polymer) obtained in steps to 7.

In Table 1, abbreviations have the following meanings.
SBL: sec-butyllithium (10.5 wt% cyclohexane solution)
THF: tetrahydrofuran HPC: hexadecylpyridinium chloride Bd: butadiene Ip: isoprene

Abbreviations in Table 2 have the following meanings.
SBL: sec-butyllithium (10.5 wt% cyclohexane solution)
TMEDA: N,N,N',N'-tetramethylethylenediamine 2-EHA: 2-ethylhexylaldehyde BzA: benzaldehyde Bd: butadiene Ip: isoprene

Table 3 shows that the hydrogenated conjugated diene-based graft polymers of Examples 1 to 6 have excellent affinity with polar materials and high thermal stability. On the other hand, the (unhydrogenated) conjugated diene-based graft polymers of Comparative Examples 1 to 4 are inferior in heat resistance. Also, the hydrogenated conjugated diene-based graft polymers of Comparative Examples 5 to 7 are inferior in affinity with polar materials.

The hydrogenated conjugated diene-based graft polymer of the present invention has excellent affinity with polar materials and high thermal stability. Therefore, the hydrogenated conjugated diene-based graft polymer of the present invention can be used for automobile interior and exterior parts, electrical and electronic parts, packaging materials, sporting goods, daily miscellaneous goods, laminated materials, elastic materials, various rubber products, medical supplies, and various other products. It can be effectively used in a wide range of fields such as adhesives and various coating primers.

Claims

A main chain (a) made of a polymer containing a conjugated diene unit and a side chain (b) made of a polymer containing at least one monomer unit selected from the group consisting of a conjugated diene unit and an aromatic vinyl compound unit including
A hydrogenated conjugated diene-based graft polymer in which at least part of the carbon-carbon double bonds contained in the conjugated diene units are hydrogenated,
The side chain (b) binds to an atom contained in a monomer unit that becomes a branched portion contained in the main chain (a),
A hydrogenated conjugated diene-based graft polymer having a hydroxyl group bonded to the main chain (a).
The hydrogenated conjugated diene-based graft polymer according to claim 1, wherein the hydroxyl groups bonded to the main chain (a) are 3.0 mol% or more.
The hydrogenated conjugated diene graft polymer according to claim 1 or 2, wherein 50 mol% or more of the carbon-carbon double bonds contained in the conjugated diene units in the hydrogenated conjugated diene graft polymer are hydrogenated. Combined.
The hydrogenated conjugated diene graft polymer according to any one of claims 1 to 3, wherein the average number of side chains (b) per molecule of the conjugated diene graft polymer is 2 or more.
the atom bonded to the side chain (b) contained in the monomer unit serving as the branched portion is not a heteroatom,
5. The connecting portion containing an atom that binds to the side chain (b) contained in the monomer unit that becomes the branch portion is not an aromatic group derived from an aromatic vinyl compound, according to any one of claims 1 to 4 The hydrogenated conjugated diene-based graft polymer described above.
(A-1) A step of lithiating anion active sites contained in the polymer (M) by reacting the polymer (M) containing a conjugated diene unit with an organolithium compound in the presence of a polar compound;
(A-2) adding a functionalizing agent to functionalize a portion of the lithiated anion active sites;
(B) adding at least one monomer selected from the group consisting of a conjugated diene and an aromatic vinyl compound to polymerize from the remaining lithiated anionic active sites in the polymer (M) to obtain a main chain (C) a step of forming a side chain on the polymer (M) to produce a conjugated diene-based graft polymer; (D) recovering the obtained conjugated diene graft polymer;
The method for producing a hydrogenated conjugated diene-based graft polymer according to any one of claims 1 to 5.
Furthermore, after step (A-2),
(A-3) adding a Lewis acid;
The method for producing a hydrogenated conjugated diene-based graft polymer according to claim 6.
(E) an active terminal polymer represented by the following formula (I) and PX (I)
(In formula (I), P represents a polymer chain containing at least one monomer unit selected from the group consisting of conjugated diene units and aromatic vinyl compound units, and X represents an anionic polymerization active terminal.) ,
A step of reacting with a functional group-modified conjugated diene polymer having an epoxy group to prepare a conjugated diene graft polymer;
(C) hydrogenating at least part of the carbon-carbon double bonds contained in the conjugated diene units in the conjugated diene graft polymer to form a hydrogenated conjugated diene graft polymer;
and (D) recovering the resulting hydrogenated conjugated diene graft polymer;
The method for producing a hydrogenated conjugated diene-based graft polymer according to any one of claims 1 to 5.
A polymer composition containing the hydrogenated conjugated diene-based graft polymer according to any one of claims 1 to 5.
A molded article obtained by molding the polymer composition according to claim 9.
A crosslinked product obtained by crosslinking the polymer composition according to claim 9.