JP7280664B2 - Conjugated diene polymer, conjugated diene polymer composition, and method for producing conjugated diene polymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a conjugated diene polymer, a conjugated diene polymer composition, and a method for producing a conjugated diene polymer.

In recent years, due to the growing interest in environmental problems, there is a strong demand for fuel saving in automobiles, and polymer compositions used for automobile tires are also required to have excellent fuel saving properties. . Polymer compositions containing conjugated diene polymers such as polybutadiene and butadiene-styrene copolymers and fillers such as carbon black and silica are used as polymer compositions for automobile tires.

For example, Patent Documents 1 and 2 disclose a polymer composition containing a conjugated diene polymer modified with a specific acrylamide compound.

JP-A-1-217003 JP-A-1-217047

However, polymer compositions using conventional conjugated diene-based polymers have not been sufficiently satisfactory in terms of fuel economy.

The problem to be solved by the present invention is a conjugated diene-based polymer capable of obtaining a polymer composition having excellent fuel efficiency, and a conjugated diene-based polymer composition containing the conjugated diene-based polymer and a filler. and to provide a method for producing the conjugated diene-based polymer.

［式中、Ｚは、酸素原子又は硫黄原子を示し、Ｒ^１、Ｒ^２及びＲ^３は、それぞれ独立に、水素原子、ヒドロカルビル基又は置換ヒドロカルビル基を示し、Ｒ^４及びＲ^５は、それぞれ独立に、ヒドロカルビル基、置換ヒドロカルビル基、シリル基又は置換シリル基を示し、Ｒ^４及びＲ^５は、結合して窒素原子と共に環構造を形成していてもよく、Ｒ^４及びＲ^５が結合した基は、ケイ素原子、窒素原子、硫黄原子及び酸素原子からなる原子群より選ばれる少なくとも一種の原子を有してもよい。］ The present invention relates to a conjugated diene-based polymer having a structural unit based on a conjugated diene, and having two or more structural units represented by the following formula (1) in one molecule of the polymer. .

[In the formula, Z represents an oxygen atom or a sulfur atom, R ¹ , R ² and R ³ each independently represent a hydrogen atom, a hydrocarbyl group or a substituted hydrocarbyl group, R ⁴ and R ⁵ each independently represents a hydrocarbyl group, a substituted hydrocarbyl group, a silyl group or a substituted silyl group, R ⁴ and R ⁵ may combine to form a ring structure together with the nitrogen atom, and the group to which R ⁴ and R ⁵ are bonded may have at least one atom selected from the group of atoms consisting of silicon atoms, nitrogen atoms, sulfur atoms and oxygen atoms. ]

The present invention also relates to a conjugated diene polymer composition containing the conjugated diene polymer described above and a filler.

［式中、Ｚは、酸素原子又は硫黄原子を示し、Ｒ^１、Ｒ^２及びＲ^３は、それぞれ独立に、水素原子、ヒドロカルビル基又は置換ヒドロカルビル基を示し、Ｒ^４及びＲ^５は、それぞれ独立に、ヒドロカルビル基、置換ヒドロカルビル基、シリル基又は置換シリル基を示し、Ｒ^４及びＲ^５は、結合して窒素原子と共に環構造を形成していてもよく、Ｒ^４及びＲ^５が結合した基は、ケイ素原子、窒素原子、硫黄原子及び酸素原子からなる群より選ばれる少なくとも一種の原子を有してもよい。］ The present invention further relates to a method for producing a conjugated diene-based polymer having the following steps A and B.
(Step A): In a hydrocarbon solvent, in the presence of an alkali metal catalyst, a monomer containing a conjugated diene is polymerized, and at least one end of the polymer chain having a structural unit based on the conjugated diene has a A step of obtaining a polymer having an alkali metal.
(Step B): A step of reacting the polymer obtained in Step A with 2 equivalents or more of a compound represented by the following formula (2) with respect to 1 equivalent of the alkali metal.

[In the formula, Z represents an oxygen atom or a sulfur atom, R ¹ , R ² and R ³ each independently represent a hydrogen atom, a hydrocarbyl group or a substituted hydrocarbyl group, R ⁴ and R ⁵ each independently represents a hydrocarbyl group, a substituted hydrocarbyl group, a silyl group or a substituted silyl group, R ⁴ and R ⁵ may combine to form a ring structure together with the nitrogen atom, and the group to which R ⁴ and R ⁵ are bonded may have at least one atom selected from the group consisting of silicon atoms, nitrogen atoms, sulfur atoms and oxygen atoms. ]

According to the present invention, a conjugated diene-based polymer capable of obtaining a polymer composition having excellent fuel economy, a conjugated diene-based polymer composition containing the conjugated diene-based polymer and a filler, and the conjugate A method for producing a diene polymer can be provided.

This embodiment will be described in detail. In addition, this invention is not limited to the following embodiment.

As used herein, hydrocarbyl groups represent hydrocarbon residues. A substituted hydrocarbyl group denotes a group in which one or more hydrogen atoms of a hydrocarbon residue have been replaced with a substituent. A hydrocarbyloxy group represents a group in which a hydrogen atom of a hydroxyl group has been replaced with a hydrocarbyl group, and a substituted hydrocarbyloxy group represents a group in which one or more hydrogen atoms of a hydrocarbyloxy group has been replaced with a substituent. In addition, the substituted silyl group represents a group in which one or more hydrogen atoms of the silyl group have been substituted with a substituent, and the substituted amino group represents a group in which one or more hydrogen atoms of the amino group have been substituted with a substituent. represents a group.

[Conjugated diene polymer]
The conjugated diene-based polymer of the present embodiment is a conjugated diene-based polymer having a structural unit based on a conjugated diene, and has two or more structural units represented by the following formula (1) in one molecule of the polymer. .

In the formula, Z represents an oxygen atom or a sulfur atom, R ¹ , R ² and R ³ each independently represent a hydrogen atom, a hydrocarbyl group or a substituted hydrocarbyl group, R ⁴ and R ⁵ each independently , a hydrocarbyl group, a substituted hydrocarbyl group, a silyl group or a substituted silyl group, ^R4 and ^R5 may be combined to form a ring structure together with the nitrogen atom, and the group to which ^R4 and ^R5 are bonded is , a silicon atom, a nitrogen atom, a sulfur atom and an oxygen atom.

Hydrocarbyl groups include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, neopentyl group, isopentyl group and n-hexyl. cycloalkyl groups such as cyclohexyl group; aryl groups such as phenyl group, methylphenyl group, ethylphenyl group and naphthyl group; and aralkyl groups such as benzyl group.

The substituted hydrocarbyl group includes, for example, a substituted hydrocarbyl group having at least one group selected from the group consisting of a nitrogen atom-containing group, an oxygen atom-containing group, a sulfur atom-containing group and a silicon atom-containing group as a substituent. is mentioned.

Examples of the group having a group having a nitrogen atom as a substituent include dialkylaminoalkyl groups such as a dimethylaminoethyl group, a diethylaminoethyl group, a dimethylaminopropyl group and a diethylaminopropyl group. Examples of groups having oxygen atom-containing groups as substituents include alkoxyalkyl groups such as methoxymethyl, methoxyethyl, ethoxymethyl, ethoxyethyl, and methoxypropyl groups. The group having a group having a silicon atom as a substituent includes, for example, a trialkylsilylalkyl group such as a trimethylsilylmethyl group; a trialkylsilyloxyalkyl group such as a tert-butyldimethylsilyloxymethyl group; a trimethoxysilylpropyl group; and a trialkoxysilylalkyl group.

The hydrocarbyl groups for R ¹ , R ² and R ³ are those having 1 to 4 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group and tert-butyl group. An alkyl group is preferred, a methyl group and an ethyl group are more preferred, and a methyl group is even more preferred. The substituted hydrocarbyl groups for R ¹ , R ² and R ³ are preferably C 1-4 alkoxyalkyl groups such as methoxymethyl, methoxyethyl, ethoxymethyl, ethoxyethyl and methoxypropyl. and ethoxyethyl groups are more preferred, and methoxymethyl groups are even more preferred.

R ¹ and R ² are preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or a methyl group, still more preferably a hydrogen atom. R ³ is preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxyalkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, from the viewpoint of improving fuel economy and economy. , a methyl group or a methoxymethyl group, more preferably a hydrogen atom or a methyl group.

The hydrocarbyl group of R ⁴ and R ⁵ is preferably an alkyl group, and the number of carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group and tert-butyl group is Alkyl groups of 1 to 4 are more preferred, and methyl and ethyl groups are even more preferred.

Substituted hydrocarbyl groups for ^R4 and ^R5 are selected from hydrocarbyloxy, trihydrocarbylsilyloxy, hydrocarbylthio, trihydrocarbylsilylthio, hydrocarbylamino, trihydrocarbylsilylamino, silyl and substituted silyl groups. You may have at least 1 sort(s) of group chosen from the following group as a substituent.

Substituted silyl groups include, for example, trialkylsilyl groups such as trimethylsilyl group, triethylsilyl group and tert-butyldimethylsilyl group. The substituted silyl group for R ⁴ and R ⁵ is preferably a trialkylsilyl group, more preferably a trimethylsilyl group.

^R4 may be a hydrocarbyl group and ^R5 may be a substituted hydrocarbyl group. In this case, R ⁴ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group, an ethyl group, an n-propyl group or an n-butyl group, a methyl group or an ethyl group. is more preferable. R ⁵ is preferably a dialkylaminoalkyl group, more preferably a dimethylaminopropyl group or a diethylaminopropyl group, even more preferably a dimethylaminopropyl group.

From the viewpoint of availability of compounds, R ⁴ and R ⁵ may combine to form a ring structure together with a nitrogen atom, and the group to which R ⁴ and R ⁵ are bonded may be a silicon atom, a nitrogen atom, or a sulfur atom. and oxygen atoms.

The group to which R ⁴ and R ⁵ are bonded has 2 to 12 carbon atoms and may have at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom and a silicon atom. valence groups. The group to which R ⁴ and R ⁵ are bonded is, for example, an _alkylene group such as a trimethylene group, a tetramethylene group, a pentamethylene group and a hexamethylene group; or an oxygen-containing group such as an oxydiethylene group and an oxydipropylene group; It may be a nitrogen-containing group such as a group represented by CH ₂ --N=CH-- or a group represented by --CH ₂ CH ₂ --NR--CH ₂ CH ₂ --. R represents an alkyl group or a substituted silyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, still more preferably a methyl group. The group to which R ⁴ and R ⁵ are bonded is preferably a nitrogen-containing group or an oxygen-containing group, more preferably a group represented by -CH ₂ CH ₂ -NR-CH ₂ CH ₂ - or an oxydiethylene group.

The conjugated diene-based polymer of the present embodiment has two or more structural units represented by formula (1) in one molecule of the polymer. may have 2 to 3000 or 2 to 300 structural units. The structural unit represented by formula (1) may be block or random.

The structural unit represented by the above formula (1) can be introduced into the conjugated diene polymer by polymerizing the compound represented by the following formula (2). That is, in the conjugated diene-based polymer of the present embodiment, the polymer chain is modified with a compound represented by the following formula (2).

In the formula, Z represents an oxygen atom or a sulfur atom, R ¹ , R ² and R ³ each independently represent a hydrogen atom, a hydrocarbyl group or a substituted hydrocarbyl group, R ⁴ and R ⁵ each independently , a hydrocarbyl group, a substituted hydrocarbyl group, a silyl group or a substituted silyl group, and R ⁴ and R ⁵ may be combined to form a ring structure together with a nitrogen atom, and the ring structure consists of a silicon atom, a nitrogen atom, It may have at least one atom selected from the group consisting of sulfur atoms and oxygen atoms.

Examples of compounds represented by formula (2) include N,N-dimethylacrylamide, N,N-diethylacrylamide, N-ethyl-N-methylacrylamide, N,N-dipropylacrylamide, N,N-diisopropyl Acrylamide, N,N-dibutylacrylamide, N,N-diphenylacrylamide, N,N-diallylacrylamide, N-methyl-N-(2-dimethylaminoethyl)acrylamide, N-methyl-N-(2-diethylaminoethyl) acrylamide, N-methyl-N-(2-methyl-2-trimethylsilylaminoethyl)acrylamide, N-methyl-N-(2-methyl-2-(tert-butyl)dimethylsilylaminoethyl)acrylamide, N-methyl- N-(2,2-bis(trimethylsilyl)aminoethyl)acrylamide, N-methyl-N-(2,2-bis(tert-butyldimethylsilyl)aminoethyl)acrylamide, N-methyl-N-(3-dimethyl aminopropyl)acrylamide, N-methyl-N-(3-diethylaminopropyl)acrylamide, N-methyl-N-(3-methyl-3-trimethylsilylaminopropyl)acrylamide, N-methyl-N-(3-methyl-3 -(tert-butyl)dimethylsilylaminopropyl)acrylamide, N-methyl-N-(3,3-bis(trimethylsilyl)aminopropyl)acrylamide, N-methyl-N-(3,3-bis(tert-butyldimethyl) silyl)aminopropyl)acrylamide, N-methyl-N-(4-dimethylaminobutyl)acrylamide, N-methyl-N-(4-diethylaminobutyl)acrylamide, N-methyl-N-(3-morpholinopropyl)acrylamide, N-methyl-N-(3-cyanopropyl)acrylamide, N-trimethylsilyl-N-(2-dimethylaminoethyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(2-dimethylaminoethyl)acrylamide, N-trimethylsilyl-N-(2-methyl-2-trimethylsilylaminoethyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(2-methyl-2-trimethylsilylaminoethyl)acrylamide, N-trimethylsilyl-N- (2-methyl-2-(tert-butyl)dimethylsilylaminoethyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(2-methyl-2-(tert-butyl)dimethylsilylaminoethyl)acrylamide, N-trimethylsilyl-N-(2,2-bis(trimethylsilyl)aminoethyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(2,2-bis(trimethylsilyl)aminoethyl)acrylamide, N-trimethylsilyl- N-(2,2-bis(tert-butyldimethylsilyl)aminoethyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(2,2-bis(tert-butyldimethylsilyl)aminoethyl)acrylamide, N-trimethylsilyl-N-(3-dimethylaminopropyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(3-dimethylaminopropyl)acrylamide, N-trimethylsilyl-N-(3-methyl-3-trimethylsilyl aminopropyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(3-methyl-3-trimethylsilylaminopropyl)acrylamide, N-trimethylsilyl-N-(3-methyl-3-(tert-butyl)dimethylsilyl aminopropyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(3-methyl-3-(tert-butyl)dimethylsilylaminopropyl)acrylamide, N-trimethylsilyl-N-(3,3-bis(trimethylsilyl) ) aminopropyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(3,3-bis(trimethylsilyl)aminopropyl)acrylamide, N-trimethylsilyl-N-(3,3-bis(tert-butyldimethylsilyl ) aminopropyl)acrylamide, N-(tert-butyl)dimethylsilyl-N-(3,3-bis(tert-butyldimethylsilyl)aminopropyl)acrylamide, and other acrylamide compounds; N-methyl-N-(2- dimethylaminoethyl) methacrylamide, N-methyl-N-(2-diethylaminoethyl) methacrylamide, N-methyl-N-(3-dimethylaminopropyl) methacrylamide, N-methyl-N-(3-diethylaminopropyl) methacrylamide, N-methyl-N-(4-dimethylaminobutyl) methacrylamide, N-methyl-N-(4-diethylaminobutyl) methacrylamide, N-methyl-N-(3-morpholinopropyl) methacrylamide, N -methacrylamide compounds such as methyl-N-(3-cyanopropyl) methacrylamide; morpholine compounds such as N-acryloylmorpholine and N-methacryloylmorpholine; N-acryloyl-N'-methylpiperazine, N-acryloyl-N'- trimethylsilylpiperazine, N-acryloyl-N'-(tert-butyl)dimethylsilylpiperazine, N-methacryloyl-N'-trimethylsilylpiperazine, N-methacryloyl-N'-(tert-butyl)dimethylsilylpiperazine, N-methacryloyl-N Piperazine compounds such as '-methylpiperazine can be mentioned.

Examples of compounds represented by formula (2) include N-methyl-N-(3-dimethylaminopropyl)acrylamide, N-methyl-N-(3-diethylaminopropyl)acrylamide, N-methyl-N-(3-dimethyl aminopropyl) methacrylamide, N-trimethylsilyl-N-(3-dimethylaminopropyl)acrylamide, N-trimethylsilyl-N-(3,3-bis(trimethylsilyl)aminopropyl)acrylamide, N-methyl-N-(3- diethylaminopropyl)methacrylamide, N-acryloylmorpholine, N-methacryloylmorpholine, N-acryloyl-N'-methylpiperazine, N-acryloyl-N'-trimethylsilylpiperazine and N-methacryloyl-N'-methylpiperazine are preferred, and N- Methyl-N-(3-dimethylaminopropyl)acrylamide, N-acryloylmorpholine and N-acryloyl-N'-methylpiperazine are more preferred. You may use the compound represented by Formula (2) individually or in combination of 2 or more types.

The Mooney viscosity (ML ₁₊₄ ) of the conjugated diene polymer is preferably 10 or more, more preferably 20 or more, from the viewpoint of strength. From the viewpoint of workability, it is preferably 200 or less, more preferably 150 or less. Mooney viscosity (ML ₁₊₄ ) is measured at 100° C. according to JIS K6300 (1994).

The vinyl bond content of the conjugated diene-based polymer is preferably 80 mol % or less, more preferably 70 mol % or less, from the viewpoint of fuel economy, with the content of conjugated diene units being 100 mol %. From the viewpoint of gripping properties, the content is preferably 10 mol% or more, more preferably 15 mol% or more, still more preferably 20 mol% or more, and particularly preferably 40 mol% or more. The amount of vinyl bond can be determined from the absorption intensity near 910 cm ⁻¹ , which is the absorption peak of the vinyl group, by infrared spectroscopic analysis.

The molecular weight distribution of the conjugated diene polymer is preferably 1-5, more preferably 1-2, from the viewpoint of fuel economy. The molecular weight distribution is obtained by measuring the number average molecular weight (Mn) and the weight average molecular weight (Mw) by gel permeation chromatography (GPC) and dividing Mw by Mn.

The conjugated diene-based polymer of the present embodiment can be produced by a production method including the following steps A and B.
(Step A): In a hydrocarbon solvent, in the presence of an alkali metal catalyst, a monomer containing a conjugated diene is polymerized, and at least one end of the polymer chain having a structural unit based on the conjugated diene has a A step of obtaining a polymer having an alkali metal.
(Step B): A step of reacting the polymer obtained in Step A with 2 equivalents or more of the compound represented by the formula (2) with respect to 1 equivalent of the alkali metal.

As the alkali metal catalyst, an alkali metal, an organic alkali metal compound, a complex of an alkali metal and a polar compound, an oligomer containing an alkali metal, or the like can be used.

Alkali metals include, for example, lithium, sodium, potassium, rubidium and cesium. Examples of organic alkali metal compounds include ethyllithium, n-propyllithium, iso-propyllithium, n-butyllithium, sec-butyllithium, tert-octyllithium, n-decyllithium, phenyllithium, 2-naphthyllithium, 2-butylphenyllithium, 4-phenylbutyllithium, cyclohexyllithium, 4-cyclopentyllithium, dimethylaminopropyllithium, diethylaminopropyllithium, tert-butyldimethylsilyloxypropyllithium, N-morpholinopropyllithium, lithium hexamethyleneimide, lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, lithium dodecamethyleneimide, 1,4-dilithio-2-butene, sodium naphthalenide, sodium biphenylide and potassium naphthalenide. Complexes of alkali metals and polar compounds include, for example, potassium-tetrahydrofuran complexes and potassium-diethoxyethane complexes. Examples of alkali metal-containing oligomers include a compound obtained by reacting 3-(dimethylamino)propyllithium or 3-(diethylamino)propyllithium with isoprene, and a sodium salt of α-methylstyrene tetramer. Among these, organic lithium compounds and organic sodium compounds are preferred as alkali metal catalysts, and organic lithium compounds and organic sodium compounds having 2 to 20 carbon atoms are more preferred. You may use an alkali metal catalyst individually or in combination of 2 or more types.

The hydrocarbon solvent is a solvent that does not deactivate the organic alkali metal compound catalyst, and aliphatic hydrocarbons, aromatic hydrocarbons, alicyclic hydrocarbons, and the like can be used. Examples of aliphatic hydrocarbons include propane, n-butane, iso-butane, n-pentane, iso-pentane, 2-methylpentane, 3-methylpentane, n-hexane, propene, 1-butene, iso-butene , trans-2-butene, cis-2-butene, 1-pentene, 2-pentene, 1-hexene and 2-hexene. Aromatic hydrocarbons include, for example, benzene, toluene, xylene and ethylbenzene. Alicyclic hydrocarbons include, for example, cyclopentane, methylcyclopentane and cyclohexane. Among these, hydrocarbons having 2 to 12 carbon atoms are preferred. The hydrocarbon solvent may be used alone or in combination of two or more, and a mixture of aliphatic and alicyclic hydrocarbons such as industrial hexane may be used.

In step A, a monomer containing a conjugated diene is polymerized to produce a polymer having an alkali metal derived from the alkali metal catalyst described above at the polymer chain end. Conjugated dienes include, for example, 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and 1,3-hexadiene. Among these, 1,3-butadiene and isoprene are preferred from the viewpoint of availability. Conjugated dienes may be used alone or in combination of two or more.

In step A, the conjugated diene may be polymerized in combination with another monomer. Other monomers include, for example, vinyl aromatics, vinyl nitriles and unsaturated carboxylic acid esters. Vinyl aromatics include styrene, α-methylstyrene, vinyltoluene, vinylnaphthalene, divinylbenzene, trivinylbenzene and divinylnaphthalene. Vinyl nitriles include, for example, acrylonitrile, and unsaturated carboxylic acid esters include methyl acrylate, ethyl acrylate, methyl methacrylate and ethyl methacrylate. Among these, aromatic vinyl is preferred, and styrene is more preferred.

From the viewpoint of strength, the monomer may contain structural units based on aromatic vinyl (aromatic vinyl units). That is, the conjugated diene-based polymer of the present embodiment may further have structural units based on aromatic vinyl. The content of the aromatic vinyl unit is preferably 10% by mass or more (the content of the conjugated diene unit is 90% by mass or less) when the total amount of the conjugated diene unit and the aromatic vinyl unit is 100% by mass. It is preferably 15% by mass or more (the content of conjugated diene units is 85% by mass or less). In addition, from the viewpoint of fuel economy, the content of the aromatic vinyl unit is preferably 50% by mass or less (the content of the conjugated diene unit is 50% by mass or more), more preferably 45% by mass or less (the conjugated diene unit content is 50% by mass or more). unit content is 55% by mass or more).

From the viewpoint of fuel efficiency, the monomer may further contain a vinyl compound represented by the following formula (3). That is, the conjugated diene-based polymer of the present embodiment may further have a structural unit based on a vinyl compound represented by the following formula (3).

In the formula, R ⁶ represents a hydrogen atom or a hydrocarbyl group, R ⁷ represents a hydrocarbylene group, m is 0 or 1, X ¹ , X ² and X ³ each independently represents a substituted amino group, hydrocarbyl or substituted hydrocarbyl groups, wherein at least one of X ¹ , X ² and X ³ is a substituted amino group.

The substituted amino groups of X ¹ , X ² and X ³ may be acyclic amino groups or cyclic amino groups.

Examples of non-cyclic amino groups include dimethylamino group, diethylamino group, di(n-propyl)amino group, di(isopropyl)amino group, di(n-butyl)amino group, di(sec-butyl)amino group, di(tert-butyl)amino group, di(neopentyl)amino group, dialkylamino group such as ethylmethylamino group; di(methoxymethyl)amino group, di(methoxyethyl)amino group, di(ethoxymethyl)amino group, di(alkoxyalkyl)amino groups such as di(ethoxyethyl)amino; and di(trialkylsilyl)amino groups such as di(trimethylsilyl)amino and di(tert-butyldimethylsilyl)amino.

Cyclic amino groups include, for example, 1-pyrrolidinyl group, 1-piperidino group, 1-hexamethyleneimino group, 1-heptamethyleneimino group, 1-octamethyleneimino group, 1-decamethyleneimino group, 1-dodecamethylene 1-polymethyleneimino group such as imino group; imidazolyl group such as 1-imidazolyl group and 4,5-dihydro-1-imidazolyl group; 1-imidazolidinyl group; 1-piperazinyl group;

The substituted amino group is preferably an acyclic amino group, more preferably a dialkylamino group, more preferably a dialkylamino group substituted with an alkyl group having 1 to 4 carbon atoms, from the viewpoint of economy and availability. , dimethylamino group, diethylamino group, di(n-propyl)amino group and di(n-butyl)amino group are more preferred.

At least one of X ¹ , X ² and X ³ is a substituted amino group, preferably two or all of X ¹ , X ² and X ³ are substituted amino groups, X ¹ , X ² and two of X ³ are more preferably substituted amino groups.

The hydrocarbyl groups of X ¹ , X ² and X ³ can include the hydrocarbyl groups described above, including methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert- An alkyl group such as a butyl group is preferred, an alkyl group having 1 to 4 carbon atoms is more preferred, and a methyl group and an ethyl group are even more preferred.

Examples of the substituted hydrocarbyl groups of X ¹ , X ² and X ³ include the substituted hydrocarbyl groups described above, and alkoxyalkyl groups such as methoxymethyl, ethoxymethyl, methoxyethyl and ethoxyethyl are preferred. An alkoxyalkyl group having 1 to 4 atoms is more preferred.

When one or two of X ¹ , X ² and X ³ is a hydrocarbyl group or a substituted hydrocarbyl group, it is preferably an alkyl group or an alkoxyalkyl group, and an alkyl group having 1 to 4 carbon atoms or is more preferably an alkoxyalkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, and even more preferably a methyl group or an ethyl group.

From the viewpoint of fuel economy and grip, the vinyl compound represented by formula (3) is preferably bis(dialkylamino)alkylvinylsilane, bis(dimethylamino)methylvinylsilane, bis(diethylamino)methylvinylsilane, bis(di (n-propyl)amino)methylvinylsilane and bis(di(n-butyl)amino)methylvinylsilane are more preferred. From the viewpoint of compound availability, bis(diethylamino)methylvinylsilane and bis(di(n-butyl)amino)methylvinylsilane are preferred as the vinyl compound represented by formula (3).

Polymerization in step A includes an agent that adjusts the amount of vinyl bonds in the conjugated diene unit, and an agent that adjusts the distribution of structural units based on monomers other than the conjugated diene unit and the conjugated diene in the conjugated diene polymer chain (hereinafter , collectively referred to as “adjusting agent”). Ether compounds, tertiary amines, phosphine compounds and the like can be used as such modifiers.

Examples of ether compounds include cyclic ethers such as tetrahydrofuran, tetrahydropyran, and 1,4-dioxane; aliphatic monoethers such as diethyl ether and dibutyl ether; ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, and diethylene glycol. Aliphatic diethers such as diethyl ether and diethylene glycol dibutyl ether; and aromatic ethers such as diphenyl ether and anisole. Tertiary amines include, for example, triethylamine, tripropylamine, tributylamine, N,N,N',N'-tetramethylethylenediamine, N,N-diethylaniline, pyridine and quinoline. Phosphine compounds include, for example, trimethylphosphine, triethylphosphine and triphenylphosphine. You may use a regulator individually or in combination of 2 or more types.

The polymerization temperature in step A is generally 25 to 100°C, preferably 35 to 90°C, more preferably 50 to 80°C. The polymerization time is usually 10 minutes to 5 hours.

In step B, a compound represented by formula (2) is used as a modifier, and two or more structural units represented by formula (1) are introduced into the polymer obtained in step A. In step B, the amount of the compound represented by formula (2) to be reacted with the polymer obtained in step A is 2 molar equivalents or more per 1 mol of the alkali metal derived from the organic alkali metal catalyst. From the viewpoint of fuel economy and grip, the amount of the compound represented by formula (2) is preferably 2 to 3000 equivalents, more preferably 2 to 300 equivalents. The rate of introduction of the compound (modifier) represented by formula (2) into the polymer is preferably 50% or more, more preferably 70% or more, and even more preferably 100%.

In step B, the temperature at which the polymer obtained in step A and the compound represented by formula (2) are reacted is generally 25 to 100°C, preferably 35 to 90°C, more preferably 50°C. ~80°C. The reaction time is generally 60 seconds to 5 hours, preferably 5 minutes to 1 hour, more preferably 15 minutes to 1 hour.

In the production method of the present embodiment, if necessary, a coupling agent may be added to the hydrocarbon solution of the conjugated diene-based polymer during the initiation and termination of the polymerization of the monomers by the alkali metal catalyst.

Examples of coupling agents include silicon tetrachloride, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, tin tetrachloride, methyltrichlorotin, dimethyldichlorotin, trimethylchlorotin, tetramethoxysilane, methyltrimethoxysilane, dimethoxydimethyl Silanes, methyltriethoxysilane, ethyltrimethoxysilane, dimethoxydiethylsilane, diethoxydimethylsilane, tetraethoxysilane, ethyltriethoxysilane and diethoxydiethylsilane.

The amount of the coupling agent added is preferably 0.03 mol or more, more preferably 0.05 mol or more per 1 mol of the alkali metal derived from the alkali metal catalyst, from the viewpoint of processability of the conjugated diene polymer. be. Also, the amount of the coupling agent added is preferably 0.4 mol or less, more preferably 0.3 mol or less, from the viewpoint of fuel economy.

The conjugated diene-based polymer is recovered by a known recovery method, for example, a method of adding a coagulant to a hydrocarbon solution of a conjugated diene-based polymer, or a method of adding steam to a hydrocarbon solution of a conjugated diene-based polymer. It can be recovered from a hydrocarbon solution of the system polymer. The recovered conjugated diene polymer may be dried with a known dryer such as a band dryer or an extrusion dryer.

[Conjugated diene polymer composition]
The conjugated diene-based polymer composition of this embodiment contains the above-described conjugated diene-based polymer and a filler.

As fillers, silica, carbon black, calcium carbonate, talc, alumina, clay, aluminum hydroxide, mica and the like can be used.

Silica includes, for example, dry silica (anhydrous silicic acid), wet silica (hydrous silicic acid), colloidal silica, precipitated silica, calcium silicate and aluminum silicate. These may be used alone or in combination of two or more.

The BET specific surface area of silica is usually 50-250 m ² /g. BET specific surface area can be measured according to ASTM D1993-03. Commercially available silica products include EVONIK's trade name "Ultrasil VN3", Tosoh Silica Co.'s trade names "NIPSIL VN3", "NIPSIL AQ", "NIPSIL ER", "NIPSIL RS-150", and Rhodia. product names such as "Zeosil 1115MP" and "Zeosil 1165MP" manufactured by

Carbon blacks include, for example, furnace black, acetylene black, thermal black, channel black and graphite. Channel blacks include, for example, EPC, MPC and CC. Furnace carbon blacks include, for example, SAF, ISAF, HAF, MAF, FEF, SRF, GPF, APF, FF, CF, SCF and ECF. Thermal blacks include, for example, FT and MT. You may use carbon black individually or in combination of 2 or more types.

The nitrogen adsorption specific surface area (N ₂ SA) of carbon black is generally 5-200 m ² /g, and the dibutyl phthalate (DBP) absorption of carbon black is generally 5-300 mL/100 g. The nitrogen adsorption specific surface area can be measured according to ASTM D4820-93, and the DBP absorption can be measured according to ASTM D2414-93. Commercially available carbon black products include "Diablack N339" manufactured by Mitsubishi Chemical Corporation, "Seist 6", "Seist 7HM" and "Seist KH" manufactured by Tokai Carbon Co., Ltd., and "Seist KH" manufactured by EVONIK. CK 3", "Special Black 4A", etc. can be used.

The content of the filler is usually 10 to 150 parts by mass with respect to 100 parts by mass of the conjugated diene polymer. The content of the filler is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, from the viewpoint of abrasion resistance and strength, and preferably 120 parts by mass or less from the viewpoint of enhancing reinforcing properties. , more preferably 100 parts by mass or less.

From the viewpoint of fuel economy, the filler preferably contains silica or carbon black. The content of silica is preferably 50 parts by mass or more, more preferably 70 parts by mass or more, based on 100 parts by mass of the total filler content. The content of carbon black is preferably 50 parts by mass or more, more preferably 70 parts by mass or more, based on 100 parts by mass of the total filler content.

The conjugated diene-based polymer composition may contain other polymer components, additives, and the like.

Other polymer components include, for example, conventional styrene-butadiene copolymer rubber, polybutadiene rubber, butadiene-isoprene copolymer rubber, butyl rubber, natural rubber, ethylene-propylene copolymer and ethylene-octene copolymer. mentioned. These polymer components may be used alone or in combination of two or more.

When other polymer components are blended, the content of the conjugated diene-based polymer of the present embodiment is the total content of the polymer components (including the content of the conjugated diene-based polymer) from the viewpoint of fuel economy. Based on 100 parts by mass, it is preferably 10 parts by mass or more, more preferably 20 parts by mass or more.

As additives, known ones can be used, vulcanizing agents such as sulfur; thiazole vulcanization accelerator, thiuram vulcanization accelerator, sulfenamide vulcanization accelerator, guanidine vulcanization accelerator vulcanization accelerators such as stearic acid, vulcanization activators such as zinc oxide; organic peroxides; silane coupling agents; extender oils;

Examples of silane coupling agents include vinyltrichlorosilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane. Silane, γ-methacryloxypropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-phenyl-γ -aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, bis(3-(triethoxysilyl)propyl)disulfide, bis(3-(tri ethoxysilyl)propyl)tetrasulfide, γ-trimethoxysilylpropyldimethylthiocarbamyltetrasulfide and γ-trimethoxysilylpropylbenzothiazyltetrasulfide. Silane coupling agents may be used alone or in combination of two or more. As commercially available products, trade names such as "Si69" and "Si75" manufactured by EVONIK can be used.

Examples of extender oils include aromatic mineral oils (viscosity specific gravity constant (VGC value) 0.900 to 1.049), naphthenic mineral oils (VGC value 0.850 ˜0.899) and paraffinic mineral oils (VGC values 0.790-0.849). The polycyclic aromatic content of the extender oil is preferably less than 3% by weight, more preferably less than 1% by weight. The polyaromatic content is measured according to the British Petroleum Institute method 346/92. The aromatic compound content (CA) of the extender oil is preferably 20% by mass or more. You may use an extender oil individually or in combination of 2 or more types.

Examples of vulcanization accelerators include thiazole-based vulcanization accelerators such as 2-mercaptobenzothiazole, dibenzothiazyldisulfide, and N-cyclohexyl-2-benzothiazylsulfenamide; tetramethylthiuram monosulfide, tetramethyl Thiuram vulcanization accelerators such as thiuram disulfide; N-cyclohexyl-2-benzothiazolesulfenamide, N-tert-butyl-2-benzothiazolesulfenamide, N-oxyethylene-2-benzothiazolesulfenamide Sulfenamide-based vulcanization accelerators such as N-oxyethylene-2-benzothiazolesulfenamide and N,N'-diisopropyl-2-benzothiazolesulfenamide; diphenylguanidine, diorthotolylguanidine, orthotolylbiguanidine and other guanidine-based vulcanization accelerators. The content of the vulcanization accelerator is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 3 parts by mass, per 100 parts by mass of the polymer component.

As a method for producing the conjugated diene-based polymer composition of the present embodiment, a known method, for example, a method of kneading each component with a known mixer such as a roll or a Banbury mixer may be used.

As kneading conditions, when a vulcanizing agent and a vulcanization accelerator are not blended, the kneading temperature is usually 50 to 200° C., preferably 80 to 190° C., and the kneading time is usually 30 seconds to 30 minutes. Yes, preferably 1 minute to 30 minutes. When a vulcanizing agent or a vulcanization accelerator is added, the kneading temperature is usually 100°C or less, preferably room temperature to 80°C. A composition containing a vulcanizing agent or a vulcanization accelerator is usually used after undergoing vulcanization treatment such as press vulcanization. The vulcanization temperature is generally 120-200°C, preferably 140-180°C.

The conjugated diene-based polymer and the conjugated diene-based polymer composition of the present embodiment are excellent in fuel efficiency, and can be used for tires, shoe soles, flooring materials, anti-vibration materials, etc., and are particularly suitable for tires. can be used for

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Physical properties were evaluated by the following methods.

1. Mooney viscosity (ML ₁₊₄ )
The Mooney viscosity of the polymer was measured at 100°C according to JIS K6300 (1994).

2. Vinyl Bond Amount The vinyl bond amount (mol %) of the conjugated diene in the polymer was obtained from the absorption intensity near 910 cm ⁻¹ , which is the absorption peak of the vinyl group, by infrared spectroscopic analysis.

3. Styrene Unit Content The styrene unit content (% by mass) of the polymer was determined from the refractive index according to JIS K6383 (1995).

4. Molecular weight distribution (Mw/Mn)
The weight average molecular weight (Mw) and number average molecular weight (Mn) are measured by gel permeation chromatography (GPC) under the following conditions (1) to (8), and the molecular weight distribution (Mw/ Mn) was determined.
(1) Apparatus: HLC-8020 manufactured by Tosoh Corporation
(2) Separation column: GMH-XL manufactured by Tosoh Corporation (2 columns in series)
(3) Measurement temperature: 40°C
(4) Carrier: Tetrahydrofuran (5) Flow rate: 0.6 mL/min (6) Injection volume: 5 μL
(7) detector: differential refraction (8) molecular weight standard: standard polystyrene

4. Modifier introduction rate to polymer Determine the moles of unreacted modifier in the polymer solution by gas chromatography (GC) method under the following conditions (1) to (7), and modify the polymer according to the following formula. The introduction rate of the agent was calculated.
Denaturant introduction rate (%) = [unreacted modifier (mol) / introduced modifier (mol)] × 100
(1) Apparatus: GC-2010 manufactured by Shimadzu Corporation
(2) Column: DB-5MS (length 30 m, inner diameter 0.25 mm, film thickness 0.25 μm, manufactured by Agilent Technologies)
(3) Inlet and transfer line temperature: 250°C
(4) Oven temperature: 150°C (held for 5 minutes) → 20°C/min → 300°C (held for 5 minutes)
(5) Carrier gas: He (0.81 mL/min)
(6) Injection volume: 1 μL
(7) Detector: FID (Detector temperature: 300°C)

5. Polymer Adsorption Rate The adsorption rate of the polymer to the column was calculated under the following conditions by a liquid chromatography (LC) method.
(Preparation of measurement sample)
A tetrahydrofuran (THF) solution containing octacosane at a concentration of about 0.2 w/v% as an internal standard was prepared, and 30 mg of the polymer was dissolved in 30 mL of the THF solution to prepare a measurement sample.
(measuring device)
As a measuring device, Shimadzu Corporation liquid feed pump: LC-20AD, degasser: DGU-20A3, autosampler: SIL-20A HT, column oven: CTO-20A, differential refractive index detector (RID): RID-10A, System controller: CBM-20A, analysis software: LC solution ver. 1.24 SP1 was used.
(Measurement condition)
As a measurement column, two LC columns: Inertsil CX (inner diameter: 4.6 mm, length: 250 mm) manufactured by GL Science were connected, and the column oven temperature was set at 30°C, and the RID cell temperature was set at 40°C. Using THF (Wako, special grade, stabilizer-free) as the mobile phase, 20 μL of sample was injected into the device and passed through the column at a flow rate of 1 mL/min.

(Calculation of adsorption rate)
The measurement sample was subjected to LC measurement under the above conditions, and in the obtained chromatogram, a baseline was drawn for the peak derived from the polymer and the internal standard peak, and the peak area was determined. As a standard sample, an unmodified styrene-butadiene copolymer (hereinafter abbreviated as "unmodified SBR") having a styrene-based structural unit content of 25% by mass and an Mw of 256,000 was prepared. A similar measurement was carried out using the same method, and the peak area was obtained. Then, the adsorption rate of the polymer was obtained from the following formula.
Adsorption rate (%) = [1-(A ₂ ×S ₁ )/(A ₁ ×S ₂ )]×100
where A ₁ is the peak area of the unmodified SBR, S ₁ is the peak area of the internal standard in the unmodified SBR, A ₂ is the peak area of the polymer, and S ₂ is the peak area of the internal standard in the polymer. indicates The standard sample is not limited to the unmodified SBR, but an unmodified styrene-butadiene copolymer having a styrene-based structural unit content of about 5 to 50% by mass and an Mw in the range of 100,000 to 1,100,000. A polymer can be used, and the content of the structural unit based on styrene is preferably 0.9 to 1.1 times that of the polymer in the measurement sample, and Mw is 0 of the Mw of the polymer in the measurement sample. 0.5 times to 1.5 times is preferable.

6. Fuel Economy A test piece having a width of 1 mm or 2 mm and a length of 40 mm was punched out from the vulcanized sheet and subjected to the test. Measurement was performed by measuring the loss tangent (tan δ (70°C)) of the test piece at a temperature of 70°C under the conditions of a strain of 1% and a frequency of 10 Hz using a viscoelasticity measuring device (manufactured by Ueshima Seisakusho Co., Ltd.). The smaller the tan δ, the better the fuel efficiency.

Example 1
<Preparation of conjugated diene polymer 1>
The interior of a stainless steel polymerization reactor having an internal volume of 5 L was washed ^, dried, and purged with dry nitrogen. 5 mL and 1.2 mL of ethylene glycol diethyl ether were charged into the polymerization reaction vessel. Next, an n-hexane solution containing 3.41 mmol of n-butyllithium (hereinafter abbreviated as “nBuLi”) was added to initiate polymerization, followed by copolymerization of 1,3-butadiene and styrene. Went for 5 hours. During the polymerization, the stirring speed was 130 rpm, the temperature inside the polymerization reactor was 65° C., and the monomer was continuously fed into the polymerization reactor. The amount of 1,3-butadiene fed was 202 g and the amount of styrene fed was 68 g.
Next, the resulting polymer solution was stirred at a stirring speed of 130 rpm, and an n -Hexane solution was added and stirred for 15 minutes, then 20 mL of n-hexane solution containing 0.21 mL of methanol was added to the polymer solution and further stirred for 5 minutes. GC measurement of the polymer solution confirmed that no unreacted MePAM remained. The adsorption rate of the polymer calculated by LC measurement was 41%.

1.8 g of 2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate (manufactured by Sumitomo Chemical Co., Ltd., trade name: Sumilizer GM) and 0.9 g of pentaerythrityl tetrakis(3-laurylthiopropionate) (manufactured by Sumitomo Chemical Co., Ltd., trade name: Sumilizer TP-D) was added, and most of the volatile matter in the polymer solution was removed at room temperature for 24 hours. After evaporating for 1 hour and drying under reduced pressure at 55° C. for 12 hours, a conjugated diene polymer 1 was obtained.

<Preparation of polymer composition and production of vulcanized sheet>
"Conjugated diene polymer 1" 100 parts by mass, silica (manufactured by EVONIK, trade name: Ultrasil VN3-GR) 78.4 parts by mass, silane coupling agent (manufactured by EVONIK, trade name: Si69) 6.4 mass part, carbon black (manufactured by Mitsubishi Chemical Corporation, trade name: Diablack N339) 6.4 parts by mass, extender oil (manufactured by Japan Energy Co., trade name: JOMO Process NC-140) 47.6 parts by mass, anti-aging agent ( Sumitomo Chemical Co., trade name: Antigen 3C) 1.5 parts by mass, stearic acid 2 parts by mass, zinc white 2 parts by mass, vulcanization accelerator (Sumitomo Chemical Co., trade name: Soxinol CZ) 1 part by mass, vulcanization Sulfur accelerator (manufactured by Sumitomo Chemical Co., Ltd., trade name: Soxinol D) 1 part by mass, wax (manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., trade name: Sannok N) 1.5 parts by mass, processing aid (manufactured by Structol Co., Ltd., Product name: 1 part by mass of EF44) and 1.4 parts by mass of sulfur are kneaded in a Laboplastomill to prepare a polymer composition containing silica as a filler (hereinafter abbreviated as “Si polymer composition”). ) was prepared. Then, the Si polymer composition was formed into a sheet with a 6-inch roll, and the sheet was vulcanized by heating at 160° C. for 55 minutes to prepare a vulcanized sheet.

"Conjugated diene polymer 1" 70 parts by mass, polybutadiene rubber (manufactured by Ube Industries, Ltd., trade name: BR150B) 30 parts by mass, carbon black (Diablack N339) 55 parts by mass, extender oil (JOMO process NC-140 ) 10 parts by mass, antioxidant (antigen 6C) 1 part by mass, stearic acid 2 parts by mass, zinc white 3 parts by mass, vulcanization accelerator (Sokucinol CZ) 1.5 parts by mass, wax (Sannok N) 2.0 Parts by mass and 1.5 parts by mass of sulfur were kneaded in a Laboplastomill to prepare a polymer composition containing carbon black as a filler (hereinafter abbreviated as "CB polymer composition"). bottom. Next, the CB polymer composition was formed into a sheet with a 6-inch roll, and the sheet was vulcanized by heating at 160° C. for 12 minutes to prepare a vulcanized sheet.

Example 2
<Preparation of conjugated diene polymer 2>
A conjugated diene polymer 2 was obtained in the same manner as in Example 1, except that the amount of MePAM added was changed from 17.1 mmol to 30.7 mmol. GC measurement of the polymer solution confirmed that no unreacted MePAM remained. The adsorption rate of the polymer calculated by LC measurement was 44%.
<Preparation of polymer composition and production of vulcanized sheet>
A Si polymer composition was prepared and a vulcanized sheet was produced in the same manner as in Example 1, except that the conjugated diene polymer 2 was used.

Comparative example 1
<Preparation of conjugated diene polymer 3>
The interior of a stainless steel polymerization reactor having an internal volume of 20 L was washed, dried, and replaced with dry nitrogen, and 10.2 kg of hexane, 606 g of 1,3-butadiene, 193 g of styrene, 6.1 mL of tetrahydrofuran, and 4.5 mL of ethylene glycol diethyl ether were added. It was put into the polymerization reaction vessel. Next, an n-hexane solution containing 11.7 mmol of nBuLi was added to initiate polymerization, and 1,3-butadiene and styrene were copolymerized for 3.0 hours. During the polymerization, the stirring speed was 130 rpm, the temperature inside the polymerization reactor was 65° C., and the monomer was continuously fed into the polymerization reactor. The feed amount of 1,3-butadiene was 909 g and the feed amount of styrene was 291 g. Next, 20 mL of a hexane solution containing 0.71 mL of methanol was introduced into the polymerization reactor, and the polymer solution was stirred for 5 minutes. The adsorption rate of the polymer calculated by LC measurement was 0%.

8.0 g of "Sumilyzer GM" and 4.0 g of "Sumilyzer TP-D" were added to the polymer solution, then most of the volatile matter in the polymer solution was evaporated at room temperature for 24 hours, and then heated to 55°C. After drying under reduced pressure for 12 hours, a conjugated diene polymer 3 was obtained.

<Preparation of polymer composition and production of vulcanized sheet>
"Conjugated diene polymer 3" 100 parts by weight, "Ultrasil VN3-GR" 80.0 parts by weight, "Si75" 6.4 parts by weight, "Diablack N339" 5.0 parts by weight, "JOMO process NC-140 40.0 parts by mass, "Antigen 6C" 2.0 parts by mass, stearic acid 2.0 parts by mass, zinc white 3.0 parts by mass, "Sokucinol CZ" 1.5 parts by mass, "Sokucinol D" 2.0 parts Parts by mass, 2.0 parts by mass of "Sannok N", 1.0 parts by mass of "EF44" and 1.5 parts by mass of sulfur were kneaded in a Laboplastomill to prepare a Si polymer composition. Then, the Si polymer composition was formed into a sheet with a 6-inch roll, and the sheet was vulcanized by heating at 160° C. for 55 minutes to prepare a vulcanized sheet.

A CB polymer composition was prepared and a vulcanized sheet was produced in the same manner as in Example 1 except that the conjugated diene polymer 3 was used.

Comparative example 2
<Preparation of conjugated diene polymer 4>
In the preparation of the conjugated diene-based polymer of Example 1, the amount of nBuLi added was changed from 3.41 mmol to 2.52 mmol, and the n-hexane solution containing 17.1 mmol of MePAM was added to N-(3-dimethylaminopropyl ) Acrylamide (hereinafter abbreviated as “PAM”) was changed to an n-hexane solution containing 25.2 mmol, and the amount of methanol added was changed from 0.21 mL to 0.15 mL. Same as in Example 1. Then, a conjugated diene polymer 4 was obtained. A GC measurement of the polymer solution confirmed that the unreacted PAM was 95% of the modifier moles charged.
<Preparation of polymer composition and production of vulcanized sheet>
A Si polymer composition was prepared and a vulcanized sheet was produced in the same manner as in Example 1 except that the conjugated diene polymer 4 was used.

Comparative example 3
<Preparation of conjugated diene polymer 5>
In the preparation of the conjugated diene-based polymer of Example 1, the amount of nBuLi added was changed from 3.41 mmol to 3.82 mmol, the amount of MePAM added was changed from 17.1 mmol to 3.82 mmol, and the amount of methanol added was changed to A conjugated diene polymer 5 was obtained in the same manner as in Example 1, except that the volume was changed from 0.21 mL to 0.23 mL. GC measurement of the polymer solution confirmed that no unreacted MePAM remained.
<Preparation of polymer composition and production of vulcanized sheet>
A Si polymer composition and a CB polymer composition were prepared in the same manner as in Example 1 except that the conjugated diene polymer 5 was used, and vulcanized sheets of each were produced.

Table 1 shows the evaluation results of Examples 1 and 2 and Comparative Examples 1 and 3. "Si" in the table corresponds to the vulcanized sheet of the Si polymer composition, and "CB" in the table corresponds to the vulcanized sheet of the CB polymer composition.

Example 3
<Preparation of conjugated diene polymer 6>
The interior of a stainless steel polymerization reactor with an internal volume of 5 L was washed, dried, and replaced with dry nitrogen, and 2.55 kg of hexane, 135 g of 1,3-butadiene, 45 g of styrene, 1.5 mL of tetrahydrofuran, and 1.2 mL of ethylene glycol diethyl ether were added. It was put into the polymerization reaction vessel. Next, 0.81 mmol of bis(diethylamino)methylvinylsilane and 2.98 mmol of nBuLi were added as n-hexane solutions to initiate polymerization, and 1,3-butadiene and styrene were copolymerized for 2.5 hours. . Further, 0.3 hours after the initiation of polymerization, an n-hexane solution containing 1.01 mmol of bis(diethylamino)methylvinylsilane was introduced into the polymerization reactor. During the polymerization, the stirring speed was 130 rpm, the temperature inside the polymerization reactor was 65° C., and the monomer was continuously fed into the polymerization reactor. The amount of 1,3-butadiene fed was 202 g and the amount of styrene fed was 68 g.
Next, the obtained polymer solution was stirred at a stirring speed of 130 rpm, an n-hexane solution containing 11.9 mmol of MePAM was added, and after stirring for 15 minutes, 0.18 mL of methanol was added to the polymer solution. 20 mL of hexane solution was added and stirred for an additional 5 minutes. GC measurement of the polymer solution confirmed that no unreacted MePAM remained.

1.8 g of "Sumilyzer GM" and 0.9 g of "Sumilyzer TP-D" are added to the polymer solution, then most of the volatile matter in the polymer solution is evaporated at room temperature for 24 hours, and further heated to 55°C. and dried under reduced pressure for 12 hours to obtain a conjugated diene polymer 6.

<Preparation of polymer composition and production of vulcanized sheet>
"Conjugated diene polymer 6" 100 parts by mass, "Ultrasil VN3-GR" 78.4 parts by mass, "Si75" 6.4 parts by mass, "Diablack N339" 6.4 parts by mass, "JOMO process NC-140 47.6 parts by mass, 1.5 parts by mass of "Antigen 3C", 2 parts by mass of stearic acid, 2 parts by mass of zinc white, 1 part by mass of "Sokucinol CZ", 1 part by mass of "Sokucinol D", 1 part of "Sannok N" .5 parts by mass, 1 part by mass of "EF44" and 1.4 parts by mass of sulfur were kneaded in a Laboplastomill to prepare a Si polymer composition. Then, the Si polymer composition was formed into a sheet with a 6-inch roll, and the sheet was vulcanized by heating at 160° C. for 55 minutes to prepare a vulcanized sheet.

Example 4
<Preparation of conjugated diene polymer 7>
The inside of a stainless steel polymerization reactor with an internal volume of 20 L was washed, dried, and replaced with dry nitrogen, and 10.2 kg of hexane, 600 g of 1,3-butadiene, 200 g of styrene, 6.1 mL of tetrahydrofuran, and 4.6 mL of ethylene glycol diethyl ether were added. It was put into the polymerization reaction vessel. Next, 3.66 mmol of bis(diethylamino)methylvinylsilane and 13.5 mmol of nBuLi were added as n-hexane solutions to initiate polymerization, and 1,3-butadiene and styrene were copolymerized for 3.0 hours. . Further, 0.4 hours after the initiation of polymerization, an n-hexane solution containing 4.88 mmol of bis(diethylamino)methylvinylsilane was introduced into the polymerization reactor. During the polymerization, the stirring speed was 130 rpm, the temperature inside the polymerization reactor was 65° C., and the monomer was continuously fed into the polymerization reactor. The feed amount of 1,3-butadiene was 900 g and the feed amount of styrene was 300 g.
Next, the polymer solution was stirred at a stirring speed of 130 rpm, an n-hexane solution containing 135 mmol of N-acryloylmorpholine (hereinafter abbreviated as "ACMO") was added, and after stirring for 15 minutes, the polymer was 20 mL of a hexane solution containing 0.82 mL of methanol was added to the solution and stirred for an additional 5 minutes. GC measurement of the polymer solution confirmed that no unreacted ACMO remained.

8.0 g of "Sumilyzer GM" and 4.0 g of "Sumilyzer TP-D" are added to the polymer solution, then most of the volatile matter in the polymer solution is evaporated at room temperature for 24 hours, and further heated to 55°C. and dried under reduced pressure for 12 hours to obtain a conjugated diene polymer 7.

<Preparation of polymer composition and production of vulcanized sheet>
A Si polymer composition was prepared and a vulcanized sheet was produced in the same manner as in Example 3 except that the conjugated diene polymer 7 was used.

Example 5
<Preparation of conjugated diene polymer 8>
The interior of a stainless steel polymerization reactor having an internal volume of 5 L was washed, dried, and replaced with dry nitrogen, and 2.55 kg of hexane, 133 g of 1,3-butadiene, 47 g of styrene, 1.5 mL of tetrahydrofuran, and 1.2 mL of ethylene glycol diethyl ether were added. It was put into the polymerization reaction vessel. Next, 0.81 mmol of bis(diethylamino)methylvinylsilane and 3.06 mmol of nBuLi were added as n-hexane solutions to initiate polymerization, and 1,3-butadiene and styrene were copolymerized for 2.5 hours. . Further, 0.3 hours after the initiation of the polymerization, 1.01 mmol of bis(diethylamino)methylvinylsilane was added as an n-hexane solution into the polymerization reactor. During the polymerization, the stirring speed was 130 rpm, the temperature inside the polymerization reactor was 65° C., and the monomer was continuously fed into the polymerization reactor. The amount of 1,3-butadiene fed was 200 g and the amount of styrene fed was 70 g.
Next, the obtained polymer solution was stirred at a stirring speed of 130 rpm, and an n-hexane solution containing 30.6 mmol of N-acryloyl-N'-methylpiperazine (hereinafter abbreviated as "AMP") was added. After stirring for 15 minutes, 20 mL of a hexane solution containing 0.19 mL of methanol was added to the polymer solution, and the mixture was further stirred for 5 minutes. GC measurement of the polymer solution confirmed that no unreacted AMP remained.

1.8 g of "Sumilyzer GM" and 0.9 g of "Sumilyzer TP-D" are added to the polymer solution, then most of the volatile matter in the polymer solution is evaporated at room temperature for 24 hours, and further heated to 55°C. and dried under reduced pressure for 12 hours to obtain a conjugated diene polymer 8.

<Preparation of polymer composition and production of vulcanized sheet>
A Si polymer composition was prepared and a vulcanized sheet was produced in the same manner as in Example 3 except that the conjugated diene polymer 8 was used.

Comparative example 4
<Preparation of conjugated diene polymer 9>
In the preparation of the conjugated diene-based polymer of Example 3, the amount of nBuLi added was changed from 2.98 mmol to 3.61 mmol, the amount of MePAM added was changed from 11.9 mmol to 3.61 mmol, and the amount of methanol added was changed to A conjugated diene polymer 9 was obtained in the same manner as in Example 3, except that the volume was changed from 0.18 mL to 0.22 mL. GC measurement of the polymer solution confirmed that no unreacted MePAM remained.
<Preparation of polymer composition and production of vulcanized sheet>
A Si polymer composition was prepared and a vulcanized sheet was produced in the same manner as in Example 3 except that the conjugated diene polymer 9 was used.

Table 2 shows the evaluation results of Examples 3 to 5 and Comparative Example 4.

Claims (6)

A conjugated diene-based polymer having a conjugated diene-based structural unit, wherein at least one end of the polymer chain of the polymer having the conjugated diene-based structural unit is modified with a compound represented by the following formula (2): , a conjugated diene-based polymer having two or more blocks of structural units represented by the following formula (1) in one molecule of the polymer.

[In the formula, Z represents an oxygen atom or a sulfur atom, R ¹ , R ² and R ³ represent a hydrogen atom, R ⁴ represents a hydrocarbyl group, and R ⁵ represents a dialkylaminoalkyl group . ] A conjugated diene-based polymer having a conjugated diene-based structural unit, wherein at least one end of the polymer chain of the polymer having the conjugated diene-based structural unit is modified with a compound represented by the following formula (2): , a conjugated diene-based polymer having two or more blocks of structural units represented by the following formula (1) in one molecule of the polymer.

[In the formula, Z represents an oxygen atom or a sulfur atom, R ¹ , R ² and R ³ represent a hydrogen atom, R ⁴ and R ⁵ each independently represent a hydrocarbyl group , R ⁴ and R ⁵ is bonded to form a ring structure with a nitrogen atom , and the group to which R ⁴ and R ⁵ are bonded has a nitrogen atom or an oxygen atom . ] A conjugated diene polymer composition comprising the conjugated diene polymer according to claim 1 or 2 and a filler. 4. The conjugated diene polymer composition according to claim 3, wherein the content of said filler is 10 to 150 parts by mass with respect to 100 parts by mass of said conjugated diene polymer. A method for producing a conjugated diene-based polymer, comprising the following steps A and B.
(Step A): In a hydrocarbon solvent, a monomer containing a conjugated diene is polymerized in the presence of an alkali metal catalyst, and at least one end of a polymer chain having a structural unit based on the conjugated diene is attached to the alkali metal catalyst. A step of obtaining a polymer having an alkali metal derived from it.
(Step B): A step of reacting the polymer obtained in Step A with 2 equivalents or more of a compound represented by the following formula (2) with respect to 1 equivalent of the alkali metal.

[In the formula, Z represents an oxygen atom or a sulfur atom, R ¹ , R ² and R ³ represent a hydrogen atom, R ⁴ represents a hydrocarbyl group, and R ⁵ represents a dialkylaminoalkyl group . ] A method for producing a conjugated diene-based polymer, comprising the following steps A and B.
(Step A): In a hydrocarbon solvent, a monomer containing a conjugated diene is polymerized in the presence of an alkali metal catalyst, and at least one end of a polymer chain having a structural unit based on the conjugated diene is attached to the alkali metal catalyst. A step of obtaining a polymer having an alkali metal derived from it.
(Step B): A step of reacting the polymer obtained in Step A with 2 equivalents or more of a compound represented by the following formula (2) with respect to 1 equivalent of the alkali metal.

[In the formula, Z represents an oxygen atom or a sulfur atom, R ¹ , R ² and R ³ represent a hydrogen atom, R ⁴ and R ⁵ each independently represent a hydrocarbyl group , R ⁴ and R ⁵ is bonded to form a ring structure with a nitrogen atom , and the group to which R ⁴ and R ⁵ are bonded has a nitrogen atom or an oxygen atom . ]