JP6630138B2 - Method for producing copolymer, copolymer, rubber composition, and rubber product - Google Patents

Description

  The present invention relates to a method for producing a copolymer, a copolymer, a rubber composition, and a rubber product.

  Since rubber products such as tires are required to have excellent fracture resistance, wear resistance, crack growth resistance, and the like, it is known to use natural rubber having excellent elasticity as a raw material. 2. Description of the Related Art In recent years, natural rubber prices have been rising due to a decrease in the resources of rubber trees. Therefore, there is a need for a synthetic rubber having the same properties as natural rubber.

  Natural rubber consists essentially of polyisoprene having a cis-1,4-bond content of almost 100%, and the molecular structure of this polymer is believed to give rise to elasticity. Based on the knowledge of this natural rubber, research has been conducted to develop a block polymer having a conjugated diene-derived portion having a high cis-1,4-bond content and a method for producing the same (for example, see Patent Document 1). .

  Conventional methods for producing a block polymer having a conjugated diene-derived portion having a high cis-1,4-bond content include (A) at least one rare earth metal compound, (B) at least one organoaluminum compound, and (C) Lewis. A method using a catalyst containing at least one acid is known (for example, see Patent Document 1).

JP-A-2002-356557

  However, in the above-mentioned conventional method, in order to obtain a copolymer having a conjugated diene-derived moiety having a high cis-1,4-bond content, for example, (i) the presence of the above-mentioned catalyst and the presence of an inert organic solvent Under the following conditions, the conjugated diene is polymerized until the conversion becomes 50% by mass or more, (ii) a polar polymer is added to the polymerization mixture, and the polymerization is carried out until the conversion becomes 30% by mass or more; and (iii) The resulting block copolymer had to be isolated and subjected to a complicated process of (iv) using 5-30% by weight of conjugated diene and 1-30% by weight of polar monomer in the reaction mixture.

Therefore, an object of the present invention is to provide a method for producing a copolymer, which can easily produce a copolymer having a conjugated diene-derived moiety having a high cis-1,4-bond content. .
Another object of the present invention is to provide a copolymer having a conjugated diene-derived moiety having a high cis-1,4-bond content. Further, another object of the present invention is to provide a rubber composition which can obtain the effects of the copolymer of the present invention. It is another object of the present invention to provide a rubber product that can obtain the effects of the copolymer of the present invention.

The method for producing the copolymer of the present invention comprises the following formula (C1): M- (AQ ¹ ) (AQ ² ) (AQ ³ ) (C1) (where M is a lanthanoid element, scandium, and AQ ¹ , AQ ² and AQ ³ are at least one selected from the group consisting of yttrium, and AQ ¹ , AQ ² and AQ ³ are functional groups containing at least one selected from nitrogen, oxygen and sulfur. Which has at least one MN bond, MO bond or MS bond), and a substituted or unsubstituted cyclopentadienyl In which a conjugated diene monomer and a polar monomer are copolymerized in the presence of a polymerization catalyst composition containing a compound (B) having at least one selected from the group consisting of a group, an indenyl group and a fluorenyl group Which is characterized in that
According to the method for producing a copolymer of the present invention, it is possible to easily produce a copolymer having a conjugated diene-derived portion having a high cis-1,4-bond content.

Here, in the method for producing a copolymer of the present invention, it is preferable that the polymerization catalyst composition further includes an organometallic compound represented by the following formula (C2). According to this configuration, the polymerization activity can be increased.
YR ¹ _a R ² _b R ³ _c (C2)
(Wherein, Y is a metal element selected from the group consisting of Group 1, Group 2, Group 12, and Group 13 elements of the periodic table, and R ¹ and R ^{2 each} have 1 to 1 carbon atoms. 10 hydrocarbon groups or hydrogen atoms, and R ³ is a hydrocarbon group having 1 to 10 carbon atoms, provided that R ¹ , R ² and R ³ may be the same or different from each other; Is a group 1 metal element, a is 1 and b and c are 0, and when Y is a group 2 or group 12 metal element, a and b are 1 And when c is 0 and Y is a Group 13 metal element, a, b and c are 1) wherein at least one of R ¹ , R ² and R ³ is different It is more preferred that According to this configuration, the catalytic activity can be increased.

  Furthermore, in the method for producing a copolymer of the present invention, the compound (B) preferably has an indenyl group. According to this configuration, the controllability of polymerization can be improved.

  Further, in the method for producing a copolymer of the present invention, it is preferable that the polymerization catalyst composition further contains an aluminoxane compound. According to this configuration, the catalytic activity in the polymerization reaction system can be further improved. Therefore, the reaction time can be further shortened, and the reaction temperature can be further increased.

Further, in the method for producing a copolymer of the present invention, the polar monomer is preferably a (meth) acrylic monomer or an acrylonitrile monomer. According to this configuration, the physical properties of the non-polar rubber can be improved, and for example, the adhesion of the polymer and the breaking strength of the polymer can be improved.
In the present specification, “(meth) acrylic” means at least one of “acrylic” and “methacrylic”.

  Further, in the method for producing a copolymer of the present invention, the conjugated diene monomer is preferably butadiene or isoprene. According to this configuration, various properties of the rubber composition, the rubber product, and the like can be improved.

The copolymer of the present invention is characterized by being produced by the above-mentioned method for producing a copolymer.
The copolymer of the present invention has a conjugated diene-derived moiety having a high cis-1,4-bond content.

The rubber composition of the present invention is characterized by containing the above-mentioned copolymer.
According to the rubber composition of the present invention, the effect of the copolymer of the present invention can be obtained.

The rubber product of the present invention is characterized by being manufactured using a rubber composition.
According to the rubber product of the present invention, the effects of the copolymer of the present invention can be obtained.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the copolymer which can manufacture easily the copolymer which has a conjugated diene origin part which has a high cis-1,4- bond content can be provided.
Further, according to the present invention, a copolymer having a conjugated diene-derived portion having a high cis-1,4-bond content can be provided. Further, according to the present invention, it is possible to provide a rubber composition which can obtain the effects of the copolymer of the present invention. Further, according to the present invention, it is possible to provide a rubber product which can obtain the effects of the copolymer of the present invention.

  Hereinafter, embodiments of a method for producing a copolymer, a copolymer, a rubber composition, and a rubber product of the present invention will be described in detail.

(Method for producing copolymer)
The method for producing a copolymer according to an example of the present invention (hereinafter, also referred to as “method for producing an example copolymer”) includes at least a polymerization reaction step and, if necessary, a monomer preparation step and a catalyst system. It includes a preparation step and other steps.

<Polymerization reaction step>
The polymerization reaction step is a step of copolymerizing a conjugated diene monomer and a polar monomer in the presence of a predetermined polymerization catalyst composition.

  The predetermined polymerization catalyst composition used in the method for producing a copolymer according to an example of the present invention needs to include the rare earth element compound (A) and the compound (B).

Conventional polymerization catalyst compositions use a catalyst comprising a metallocene-type cation complex of a gadolinium compound as a main catalyst. Here, in order to dissolve the compound of the main catalyst, a relatively toxic and expensive aromatic hydrocarbon (such as toluene) is required as a solvent for the polymerization reaction. Therefore, with the conventional polymerization catalyst composition, there was a possibility that the copolymer could not be produced while sufficiently reducing the environmental load and the production cost.
The polymerization catalyst composition of the present invention uses the rare earth element compound (A) as a main catalyst and the compound (B) as an additive. Here, the main catalyst and the additive can be dissolved in a solvent (hexane or the like) other than the aromatic hydrocarbon (toluene or the like), and as a solvent for the polymerization reaction, the toxicity and the price are relatively high. Does not require aromatic hydrocarbons. In other words, the need for a relatively toxic and expensive aromatic hydrocarbon as a solvent for the polymerization reaction can be reduced. Therefore, according to the polymerization catalyst composition of the present invention, a copolymer can be produced while reducing environmental load and production cost.

  In the polymerization catalyst composition of the present invention, the compound (B) that can function as a conjugated ligand in the reaction system is used as an additive. Here, the compound (B) plays a role of improving the catalytic activity in the reaction system. Therefore, according to the polymerization catalyst composition of the present invention, the reaction time required for polymerization can be relatively short, and the reaction temperature required for polymerization can be relatively high, so that the robustness of the polymerization reaction system can be increased. .

-Polymerization catalyst composition-
Hereinafter, the details of the predetermined polymerization catalyst composition will be described.
The predetermined polymerization catalyst composition is
A rare earth element compound (A) (hereinafter also referred to as “component (A)”);
A compound (B) (hereinafter also referred to as “component (B)”);
Need to be included.
This predetermined polymerization catalyst composition,
-Organometallic compounds (hereinafter also referred to as "component (C)")
-Aluminoxane compound (hereinafter, also referred to as "component (D)")
-Halogen compound (hereinafter, also referred to as "component (E)")
・ Ionic compounds (hereinafter also referred to as “component (F)”)
May be further included.

  The predetermined polymerization catalyst composition preferably has high solubility in aliphatic hydrocarbons, and preferably forms a homogeneous solution in the aliphatic hydrocarbons. Here, examples of the aliphatic hydrocarbon include hexane, cyclohexane, and pentane.

It is preferable that the predetermined polymerization catalyst composition does not contain an aromatic hydrocarbon. Here, examples of the aromatic hydrocarbon include benzene, toluene, xylene and the like.
Here, “containing no aromatic hydrocarbon” means that the ratio of the aromatic hydrocarbon contained in the polymerization catalyst composition is less than 0.1% by weight.

--- Rare earth element compound (A) ((A) component)-
The component (A) can be a rare earth element compound (A) or a reaction product of the rare earth element compound (A) and a Lewis base.
Examples of the rare earth element compound (A) include scandium, yttrium, and a compound containing a lanthanoid element composed of elements having atomic numbers of 57 to 71. The lanthanoid element is specifically lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium.
Examples of the Lewis base include tetrahydrofuran, diethyl ether, dimethylaniline, trimethylphosphine, lithium chloride, neutral olefins, neutral diolefins, and the like.

  Here, the rare earth element compound (A) or a reaction product of the rare earth element compound (A) and a Lewis base preferably does not have a bond between the rare earth element and carbon. When the reaction product of the rare earth element compound (A) and the Lewis base does not have a rare earth element-carbon bond, the reaction product is stable and easy to handle.

  The component (A) may be used alone or in combination of two or more.

The rare earth element compound (A) described above has the following formula (C1):
M− (AQ ¹ ) (AQ ² ) (AQ ³ ) (C1)
(Wherein M is at least one selected from the group consisting of lanthanoid elements, scandium, and yttrium, and AQ ¹ , AQ ² and AQ ³ are at least one selected from nitrogen, oxygen and sulfur. Functional groups contained therein, which may be the same or different, provided that they have at least one MN bond, MO bond or MS bond).
With respect to M, the lanthanoid element is an element having an atomic number of 57 to 71, and specifically, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium , Ytterbium and lutetium.
Further, regarding AQ ¹ , AQ ² and AQ ³ , examples of the nitrogen-containing functional group include an amide group. Here, examples of the amide group include an aliphatic amide group such as a dimethylamide group, a diethylamide group and a diisopropylamide group; a phenylamide group, a 2,6-di-tert-butylphenylamide group, and a 2,6-diisopropylphenyl Amide group, 2,6-dineopentylphenylamide group, 2-tert-butyl-6-isopropylphenylamide group, 2-tert-butyl-6-neopentylphenylamide group, 2-isopropyl-6-neopentylphenyl An arylamide group such as an amide group and a 2,4,6-tri-tert-butylphenylamide group; a bistrialkylsilylamide group such as a bistrimethylsilylamide group; and particularly, from the viewpoint of solubility in aliphatic hydrocarbons. And a bistrimethylsilylamide group are preferred.
With respect to AQ ¹ , AQ ² and AQ ³ , the functional group containing oxygen includes a group represented by RO—, a group represented by R—CO ₂ —, and (RC (＝ O) —) ₂ CH. - a group or the like can be mentioned formula, the functional group containing sulfur, groups represented by RS-, R-CS ₂ - group represented by, (R-C (= S ) -) 2 CH- in And the like. Here, R represents an alkyl group, preferably an alkyl group having 1 to 10 carbon atoms, which may be the same or different.

The rare earth element compound (A) preferably does not have a bond between the rare earth element and carbon. When the rare earth element compound (A) does not have a rare earth element-carbon bond, the reaction product is stable and easy to handle.
The rare earth element compound (A) may be used alone or in combination of two or more.

The rare earth element compound (A) has the following formula (I _′ ):
M− (NQ ¹ ) (NQ ² ) (NQ ³ ) (I _′ )
(Wherein M represents at least one element selected from the group consisting of scandium, yttrium, and lanthanoid elements; NQ ¹ , NQ ² and NQ ³ represent amide groups, and Which may be different; having three MN bonds).
According to the above configuration, the rare earth element compound (A) can be a compound having three M-N bonds, each bond is chemically equivalent, and the structure of the compound is stable, so that handling is easy. It becomes.
Further, with the above configuration, the catalytic activity in the polymerization reaction system can be further improved. Therefore, the reaction time can be further shortened, and the reaction temperature can be further increased.

As M in the above formula (I _′ ), gadolinium is particularly preferred from the viewpoint of enhancing the catalytic activity and the reaction controllability.
In the formula (I _′ ), examples of the amide group represented by NQ ¹ , NQ ² and NQ ³ include, for example, an aliphatic amide group such as a dimethylamide group, a diethylamide group and a diisopropylamide group; 2,6-di-tert-butylphenylamide group, 2,6-diisopropylphenylamide group, 2,6-dineopentylphenylamide group, 2-tert-butyl-6-isopropylphenylamide group, 2-tert- Arylamide groups such as butyl-6-neopentylphenylamide group, 2-isopropyl-6-neopentylphenylamide group, 2,4,6-tri-tert-butylphenylamide group; bistrialkyl groups such as bistrimethylsilylamide group And a silylamide group, particularly from the viewpoint of solubility in aliphatic hydrocarbons. Bistrimethylsilylamido group. The amide groups may be used alone or in combination of two or more.

--- Compound (B) (component (B))-
The aforementioned compound (B) is selected from the group consisting of substituted or unsubstituted cyclopentadiene, indene and fluorene, that is, cyclopentadiene, substituted cyclopentadiene compound, indene, substituted indene compound, fluorene and substituted fluorene compound.
Here, examples of the substituent of the substituted cyclopentadiene compound, the substituted indene compound, and the substituted fluorene compound include a hydrocarbyl group and a metalloid group, and the hydrocarbyl group preferably has 1 to 20 carbon atoms, and preferably has 1 to 10 carbon atoms. Is still more preferable, and more preferably 1 to 8. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of metalloids of the metalloid group include germyl Ge, stannyl Sn, and silyl Si.The metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group of the metalloid group is the same as the above-mentioned hydrocarbyl group. is there. Specific examples of the metalloid group include a trimethylsilyl group.
The above cyclopentadiene and substituted cyclopentadiene compounds have a cyclopentadienyl group. Here, examples of the substituted cyclopentadiene compound include tetramethylcyclopentadiene and pentamethylcyclopentadiene.
The indene and substituted indene compounds have an indenyl group. Here, examples of the substituted indene compound include 2-phenyl-1H-indene, 3-benzyl-1H-indene, 3-methyl-2-phenyl-1H-indene, and 3-benzyl-2-phenyl-1H-indene. , 1-benzyl-1H-indene, etc., and from the viewpoint of reducing the molecular weight distribution, 3-benzyl-1H-indene and 1-benzyl-1H-indene are particularly preferred.
Further, the fluorene and the substituted fluorene compound have a fluorenyl group. Here, examples of the substituted fluorene compound include trimethylsilylfluorene and 9-methyl-9H-fluorene.
According to the configuration, the conjugated electrons of the compound (B) can be increased, and the catalytic activity in the polymerization reaction system can be further improved. Therefore, the reaction time can be further shortened, and the reaction temperature can be further increased.

  The amount of the compound (B) used is preferably more than 0 mol, more preferably 0.5 mol or more based on 1 mol of the rare earth element compound (A) from the viewpoint of sufficiently obtaining the catalytic activity. It is particularly preferably at least 1 mol, and from the viewpoint of suppressing a decrease in catalytic activity, the amount is preferably at most 3 mol, more preferably at most 2.5 mol, based on 1 mol of the rare earth element compound (A). It is particularly preferably 2.2 mol or less.

--- Organometallic compound (component (C))-
Examples of the component (C) include a compound represented by the formula (C2).
YR ¹ _a R ² _b R ³ _c (C2)
(Wherein, Y is a metal element selected from the group consisting of Group 1, Group 2, Group 12, and Group 13 elements of the periodic table, and R ¹ and R ^{2 each} have 1 to 1 carbon atoms. 10 hydrocarbon groups or hydrogen atoms, and R ³ is a hydrocarbon group having 1 to 10 carbon atoms, provided that R ¹ , R ² and R ³ may be the same or different from each other; Is a group 1 metal element, a is 1 and b and c are 0, and when Y is a group 2 or group 12 metal element, a and b are 1 And c is 0, and when Y is a Group 13 metal element, a, b and c are 1)
Here, from the viewpoint of increasing the catalytic activity, it is preferable that R ¹ , R ² and R ³ in formula (C2) are not all the same.

Specifically, the component (C) is represented by the formula (C3)
AlR ⁴ R ⁵ R ⁶ ... (C3)
(Wherein, R ⁴ and R ⁵ are a hydrocarbon group or a hydrogen atom having 1 to 10 carbon atoms, R ⁶ is a hydrocarbon group having 1 to 10 carbon atoms, and R ⁴ , R ⁵ and R ⁶ May be the same or different).
Examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-t-butylaluminum, tripentylaluminum, and trihexyl. Aluminum, tricyclohexyl aluminum, trioctyl aluminum; diethyl aluminum hydride, di-n-propyl aluminum hydride, di-n-butyl aluminum hydride, diisobutyl aluminum hydride, dihexyl aluminum hydride, diisohexyl aluminum hydride, Dioctyl aluminum hydride, diisooctyl aluminum hydride; ethyl aluminum dihydride, n-propyl aluminum Dihydride, it includes isobutyl aluminum dihydride and the like, particularly, triethylaluminum, triisobutylaluminum, hydrogenated diethylaluminum, preferably diisobutylaluminum hydride, more particularly, diisobutylaluminum hydride are preferred.
The organoaluminum compound may be used alone or in combination of two or more.

--- Aluminoxane compound (component (D))-
The component (D) is a compound obtained by bringing an organic aluminum compound into contact with a condensing agent.
By using the component (D), the catalytic activity in the polymerization reaction system can be further improved. Therefore, the reaction time can be further shortened, and the reaction temperature can be further increased.

Here, examples of the organoaluminum compound include trialkylaluminums such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, and mixtures thereof. In particular, trimethylaluminum and a mixture of trimethylaluminum and tributylaluminum are preferable.
Examples of the condensing agent include water and the like.

As the component (D), for example, the formula (S4)
− (Al (R ¹⁰ ) O) _n − (S4)
(Wherein, R ¹⁰ is a hydrocarbon group having 1 to 10 carbon atoms, wherein the halogen and / or may be substituted with an alkoxy group in some hydrocarbon group; R ¹⁰ is between the repeating units May be the same or different; n is 5 or more)
And an aluminoxane represented by

The molecular structure of the aluminoxane may be linear or cyclic.
n is preferably 10 or more.
Examples of the hydrocarbon group for R ¹⁰ include a methyl group, an ethyl group, a propyl group, and an isobutyl group, and a methyl group is particularly preferable. The above hydrocarbon groups may be used alone or in combination of two or more. As the hydrocarbon group for R, a combination of a methyl group and an isobutyl group is preferable.

The aluminoxane preferably has high solubility in aliphatic hydrocarbons, and preferably has low solubility in aromatic hydrocarbons. For example, aluminoxane which is commercially available as a hexane solution is preferable.
Here, the aliphatic hydrocarbon includes hexane, cyclohexane and the like.

The component (D) is particularly represented by the formula (S5)
_{- (Al (CH 3) x} (i-C 4 H 9) y O) m - ··· (S5)
(Where x + y is 1; m is 5 or more)
(Hereinafter, also referred to as “TMAO”). As the TMAO, for example, a product name: TMAO341 manufactured by Tosoh Fine Chemical Co., Ltd. may be mentioned.

In addition, the component (D) is particularly represented by the formula (S6)
_{- (Al (CH 3) 0.7} (i-C 4 H 9) 0.3 O) k - ··· (S6)
(Where k is 5 or more)
May be used as the modified aluminoxane (hereinafter, also referred to as “MMAO”). As the MMAO, for example, a product name: MMAO-3A manufactured by Tosoh Fine Chemical Co., Ltd. may be mentioned.

Furthermore, the component (D) is particularly represented by the formula (S7)
− [(CH ₃ ) AlO] _i − (S7)
(Where i is 5 or more)
(Hereinafter, also referred to as “PMAO”). As the PMAO, for example, a product name: TMAO-211 manufactured by Tosoh Fine Chemical Co., Ltd. can be mentioned.

  The component (D) is preferably MMAO or TMAO among the above-mentioned MMAO, TMAO, and PMAO from the viewpoint of enhancing the effect of improving the catalytic activity, and particularly, from the viewpoint of further enhancing the effect of improving the catalytic activity, TMAO Is more preferable.

--- Halogen compound (component (E))-
As the component (E), for example, a halogen-containing compound which is a Lewis acid (hereinafter, also referred to as “component (E-1)”), a complex compound of a metal halide and a Lewis base (hereinafter, “(E-2) Component), and at least one compound selected from the group consisting of organic compounds containing an active halogen (hereinafter, also referred to as “component (E-3)”).

These compounds react with the component (A), that is, a rare earth element-containing compound having an MN bond or a reaction product of the rare earth element-containing compound and a Lewis base to form a cationic transition metal compound, a halogenated transition A metal compound and / or a transition metal compound in a state where electrons are deficient in the transition metal center are generated.
By using the component (E), the cis-1,4-bond content of the conjugated diene polymer can be improved.

As the component (E-1), for example, a halogen-containing compound containing an element of Group 3, Group 4, Group 5, Group 6, Group 8, Group 13, Group 14, or Group 15, and the like In particular, an aluminum halide or an organic metal halide is preferable.
Examples of the halogen-containing compound that is a Lewis acid include titanium tetrachloride, tungsten hexachloride, tri (pentafluorophenyl) borate, methylaluminum dibromide, methylaluminum dichloride, ethylaluminum dibromide, ethylaluminum dichloride, and butylaluminum dibromide , Butyl aluminum dichloride, dimethyl aluminum bromide, dimethyl aluminum chloride, diethyl aluminum bromide, diethyl aluminum chloride, dibutyl aluminum bromide, dibutyl aluminum chloride, methyl aluminum sesquibromide, methyl aluminum sesquichloride, ethyl aluminum sesquibromide, ethyl aluminum sesquichloride, aluminum G Bromide, tri (pentafluorophenyl) aluminum, dibutyltin dichloride, tin tetrachloride, phosphorus trichloride, phosphorus pentachloride, antimony trichloride, antimony pentachloride, etc., in particular, ethyl aluminum dichloride, ethyl aluminum dibromide, diethyl Aluminum chloride, diethylaluminum bromide, ethylaluminum sesquichloride and ethylaluminum sesquibromide are preferred.
As the halogen, chlorine or bromine is preferable.
The halogen-containing compound that is the Lewis acid may be used alone or in combination of two or more.

As the metal halide used for the component (E-2), for example, beryllium chloride, beryllium bromide, beryllium iodide, magnesium chloride, magnesium bromide, magnesium iodide, calcium chloride, calcium bromide, calcium iodide, Barium chloride, barium bromide, barium iodide, zinc chloride, zinc bromide, zinc iodide, cadmium chloride, cadmium bromide, cadmium iodide, mercury chloride, mercury bromide, mercury iodide, manganese chloride, manganese bromide , Manganese iodide, rhenium chloride, rhenium bromide, rhenium iodide, copper chloride, copper iodide, silver chloride, silver bromide, silver iodide, gold chloride, gold iodide, gold bromide, and the like. , Magnesium chloride, calcium chloride, barium chloride, zinc chloride, manganese chloride, copper chloride are preferred, and magnesium chloride is particularly preferred. Zinc chloride, manganese chloride, copper chloride are preferable.
As the Lewis base used for the component (E-2), a phosphorus compound, a carbonyl compound, a nitrogen compound, an ether compound, and an alcohol are preferable.
For example, tributyl phosphate, tri-2-ethylhexyl phosphate, triphenyl phosphate, tricresyl phosphate, triethylphosphine, tributylphosphine, triphenylphosphine, diethylphosphinoethane, diphenylphosphinoethane, acetylacetone, benzoylacetone, propio Nitrile acetone, valeryl acetone, ethyl acetyl acetone, methyl acetoacetate, ethyl acetoacetate, phenyl acetoacetate, dimethyl malonate, diethyl malonate, diphenyl malonate, acetic acid, octanoic acid, 2-ethylhexanoic acid, oleic acid, stearic acid , Benzoic acid, naphthenic acid, versatic acid, triethylamine, N, N-dimethylacetamide, tetrahydrofuran, diphenyl ether, 2-ethylhexyl alcohol, oley Alcohol, stearyl alcohol, phenol, benzyl alcohol, 1-decanol, lauryl alcohol and the like are mentioned. In particular, tri-2-ethylhexyl phosphate, tricresyl phosphate, acetylacetone, 2-ethylhexanoic acid, versatic acid, 2-ethylhexyl alcohol , 1-decanol and lauryl alcohol are preferred.
The number of moles of the Lewis base is 0.01 to 30 moles, preferably 0.5 to 10 moles, per mole of the metal halide. Use of the reaction product with the Lewis base can reduce the amount of metal remaining in the polymer.

  Examples of the component (E-3) include benzyl chloride and the like.

--- Ionic compound (component (F))-
The ionic compound (component (F)) comprises a non-coordinating anion and a cation, and reacts with the rare earth element compound as the component (A) or a reaction product thereof with a Lewis base to form a cationic transition metal compound. And the like.

  Examples of the non-coordinating anion (eg, tetravalent boron anion) include tetraphenyl borate, tetrakis (monofluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, and tetrakis ( (Tetrafluorophenyl) borate, tetrakis (pentafluorophenyl) borate, tetrakis (tetrafluoromethylphenyl) borate, tetra (tolyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluoro Phenyl), phenyl] borate, and tridecahydride-7,8-dicarboundecaborate.

On the other hand, examples of the cation include a carbonium cation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptatrienyl cation, and a ferrocenium cation having a transition metal.
Specific examples of the above carbonium cation include trisubstituted carbonium cations such as triphenylcarbonium cation and tri (substituted phenyl) carbonium cation, and more specifically, as tri (substituted phenyl) carbonyl cation. Examples thereof include a tri (methylphenyl) carbonium cation and a tri (dimethylphenyl) carbonium cation. Specific examples of the ammonium cation include trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tripropylammonium cation, and tributylammonium cation (for example, tri (n-butyl) ammonium cation); N, N-dimethylanilinium Cations, N, N-dialkylanilinium cations such as N, N-diethylanilinium cation, N, N-2,4,6-pentamethylanilinium cation; dialkylammonium cations such as diisopropylammonium cation and dicyclohexylammonium cation; And the like.
Specific examples of the above phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation.

Therefore, as the ionic compound (component (F)), a compound selected and combined from the above-mentioned non-coordinating anions and cations is preferable. Specifically, N, N-dimethylanilinium tetrakis (pentafluorophenyl) ) Borate, triphenylcarboniumtetrakis (pentafluorophenyl) borate and the like are preferred.
These ionic compounds ((F) component) can be used alone or in combination of two or more. Incidentally, the content of the ionic compound in the first polymerization catalyst composition is preferably 0.1 to 10 times mol, more preferably about 1 time mol, to the component (A).

  Hereinafter, the weight ratio between the components of one example of the polymerization catalyst composition will be described.

  The molar ratio of the component (B) (compound (B)) to the component (A) (rare earth element compound (A)) is preferably more than 0, more preferably 0.5 or more, from the viewpoint of obtaining sufficient catalytic activity. And 1 or more are particularly preferable, and from the viewpoint of suppressing a decrease in catalytic activity, 3 or less are preferable, 2.5 or less are more preferable, and 2.2 or less are particularly preferable.

  The ratio of the component (C) (organometallic compound) in mole to the component (A) is preferably 1 or more, more preferably 5 or more, from the viewpoint of improving the catalytic activity in the reaction system. In respect of suppression, 50 or less is preferable, 30 or less is more preferable, and specifically, about 10 is preferable.

  The molar ratio of aluminum in the component (A) to the rare earth element in the component (A) is preferably 10 or more, more preferably 100 or more, from the viewpoint of improving the catalytic activity in the reaction system. From the viewpoint of suppressing a decrease in the catalyst activity in the above, it is preferably 1,000 or less, more preferably 800 or less.

From the viewpoint of improving the catalytic activity, the molar ratio of the component (E) (halogen compound) to the component (A) is preferably 0 or more, more preferably 0.5 or more, particularly preferably 1.0 or more. From the viewpoint of maintaining the solubility of the component and suppressing a decrease in the catalytic activity, the number is preferably 20 or less, more preferably 10 or less.
Therefore, according to the above range, the effect of improving the cis-1,4-bond content of the conjugated diene polymer can be enhanced.

In addition, the predetermined polymerization catalyst composition includes a non-coordinating anion (for example, a tetravalent boron anion) and a cation (for example, a carbonium cation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptatrienyl cation, (Ferrocenium cation having a transition metal, etc.). Here, the ionic compound has high solubility in aromatic hydrocarbons and low solubility in hydrocarbons. Therefore, if a polymerization catalyst composition containing no ionic compound is used, a conjugated diene polymer can be produced while further reducing the environmental burden and production cost.
In addition, "not containing an ionic compound" means that the ratio of the ionic compound contained in the polymerization catalyst composition is less than 0.01% by weight.

  Further, it is also possible to carry out the polymerization using the following first to fourth polymerization catalyst compositions.

--- First polymerization catalyst composition--
The first polymerization catalyst composition has the following general formula (I):
( ^Wherein , M represents a lanthanoid element, scandium or yttrium, Cp ^R each independently represents unsubstituted or substituted indenyl, and R ^{a to} R ^f each independently represent an alkyl group having 1 to 3 carbon atoms. L represents a neutral Lewis base, w represents an integer of 0 to 3), and a metallocene complex represented by the following general formula (II):
( ^Wherein , M represents a lanthanoid element, scandium or yttrium, Cp ^R each independently represents unsubstituted or substituted indenyl, and X ′ represents a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group, an amide group. , A silyl group or a hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, w represents an integer of 0 to 3), and a metallocene complex represented by the following general formula (III ):
( ^Wherein , M represents a lanthanoid element, scandium or yttrium, Cp ^R ′ represents unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl, X represents a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group. , An amide group, a silyl group or a hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, w represents an integer of 0 to 3, and [B] ⁻ represents a non-coordinating group. At least one complex selected from the group consisting of half metallocene cation complexes represented by an anion).

  Here, the metallocene complex is a complex compound in which one or more cyclopentadienyl or a derivative thereof is bonded to a central metal, and in particular, a cyclopentadienyl or a derivative thereof bonded to a central metal is one. A certain metallocene complex may be referred to as a half metallocene complex. An olefin is an aliphatic unsaturated hydrocarbon having at least one carbon-carbon double bond.

  The first polymerization catalyst composition is selected from the group consisting of metallocene complexes represented by the general formulas (I) and (II), and half metallocene cation complexes represented by the general formula (III). It preferably contains at least one kind of complex and further contains other components contained in a polymerization catalyst composition containing a usual metallocene complex, such as a cocatalyst.

In the metallocene complexes represented by the general formulas (I) and (II), Cp ^R in the formula is unsubstituted indenyl or substituted indenyl. Cp ^R of the indenyl ring as a basic skeleton may be represented by C ₉ H _7-X R X or _{C 9 H 11-X R X} . Here, X is an integer of 0-7 or 0-11. Further, it is preferable that each R is independently a hydrocarbyl group or a metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of metalloids of the metalloid group include germyl Ge, stannyl Sn, and silyl Si.The metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group of the metalloid group is the same as the above-mentioned hydrocarbyl group. is there. Specific examples of the metalloid group include a trimethylsilyl group. Specific examples of the substituted indenyl include 2-phenylindenyl, 2-methylindenyl and the like. Incidentally, the two Cp ^R in the general formula (I) and formula (II) may each be the same or different from each other.

In the half metallocene cation complex represented by the general formula (III), Cp ^R ′ in the formula is unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl, and among these, unsubstituted or substituted indenyl It is preferable that Cp ^R 'having a basic skeleton a cyclopentadienyl ring, represented by _{C 5 H 5-X R X} . Here, X is an integer of 0-5. Further, it is preferable that each R is independently a hydrocarbyl group or a metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of metalloids of the metalloid group include germyl Ge, stannyl Sn, and silyl Si.The metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group of the metalloid group is the same as the above-mentioned hydrocarbyl group. is there. Specific examples of the metalloid group include a trimethylsilyl group. Specific examples of Cp ^R ′ having a cyclopentadienyl ring as a basic skeleton include the following.
(In the formula, R represents a hydrogen atom, a methyl group or an ethyl group.)

In formula (III), Cp ^R ′ having the above-mentioned indenyl ring as a basic skeleton is defined in the same manner as Cp ^{R in} formula (I), and preferred examples are also the same.

In the general formula (III), Cp ^R 'having a basic skeleton of the above fluorenyl ring may be represented by C ₁₃ H _9-X R _X or _{C 13 H 17-X R X} . Here, X is an integer of 0-9 or 0-17. Further, it is preferable that each R is independently a hydrocarbyl group or a metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of metalloids of the metalloid group include germyl Ge, stannyl Sn, and silyl Si.The metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group of the metalloid group is the same as the above-mentioned hydrocarbyl group. is there. Specific examples of the metalloid group include a trimethylsilyl group.

  The central metal M in the general formulas (I), (II) and (III) is a lanthanoid element, scandium or yttrium. The lanthanoid elements include 15 elements having atomic numbers 57 to 71, and any of these elements may be used. Preferable examples of the central metal M include samarium Sm, neodymium Nd, praseodymium Pr, gadolinium Gd, cerium Ce, holmium Ho, scandium Sc and yttrium Y.

The metallocene complex represented by the general formula (I) contains a silylamide ligand [—N (SiR ₃ ) ₂ ]. The R groups (R ^{a to} R ^f in the general formula (I)) contained in the silylamide ligand are each independently an alkyl group having 1 to 3 carbon atoms or a hydrogen atom. Further, at least one of R ^{a to} R ^f is preferably a hydrogen atom. By making at least one of R ^{a to} R ^f a hydrogen atom, the synthesis of the catalyst is facilitated, and the bulk around silicon is reduced, so that a non-conjugated olefin is easily introduced. Further, as the alkyl group, a methyl group is preferable.

The metallocene complex represented by the general formula (II) contains a silyl ligand [—SiX ′ ₃ ]. X ′ contained in the silyl ligand [—SiX ′ ₃ ] is a group defined in the same manner as X in the general formula (III) described below, and preferred groups are also the same.

  In the general formula (III), X is a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group, an amide group, a silyl group, and a hydrocarbon group having 1 to 20 carbon atoms. Here, examples of the alkoxide group include an aliphatic alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, and a tert-butoxy group; -tert-butylphenoxy group, 2,6-diisopropylphenoxy group, 2,6-dineopentylphenoxy group, 2-tert-butyl-6-isopropylphenoxy group, 2-tert-butyl-6-neopentylphenoxy group, An aryl oxide group such as a 2-isopropyl-6-neopentylphenoxy group is exemplified, and among these, a 2,6-di-tert-butylphenoxy group is preferable.

  In the general formula (III), examples of the thiolate group represented by X include thiomethoxy, thioethoxy, thiopropoxy, thio n-butoxy, thioisobutoxy, thiosec-butoxy, and thiotert-butoxy groups. Aliphatic thiolate group; thiophenoxy group, 2,6-di-tert-butylthiophenoxy group, 2,6-diisopropylthiophenoxy group, 2,6-dineopentylthiophenoxy group, 2-tert-butyl-6-isopropyl Arylthiolate groups such as thiophenoxy group, 2-tert-butyl-6-thioneopentylphenoxy group, 2-isopropyl-6-thioneopentylphenoxy group, and 2,4,6-triisopropylthiophenoxy group; Among these, a 2,4,6-triisopropylthiophenoxy group is preferred.

  In the general formula (III), the amide group represented by X includes an aliphatic amide group such as a dimethylamide group, a diethylamide group, a diisopropylamide group; a phenylamide group, a 2,6-di-tert-butylphenylamide group, 2,6-diisopropylphenylamide group, 2,6-dineopentylphenylamide group, 2-tert-butyl-6-isopropylphenylamide group, 2-tert-butyl-6-neopentylphenylamide group, 2-isopropyl- An arylamide group such as a 6-neopentylphenylamide group, a 2,4,6-tert-butylphenylamide group; a bistrialkylsilylamide group such as a bistrimethylsilylamide group; and among these, a bistrimethylsilylamide group is exemplified. preferable.

  In the general formula (III), examples of the silyl group represented by X include a trimethylsilyl group, a tris (trimethylsilyl) silyl group, a bis (trimethylsilyl) methylsilyl group, a trimethylsilyl (dimethyl) silyl group, and a triisopropylsilyl (bistrimethylsilyl) silyl group. Among these, a tris (trimethylsilyl) silyl group is preferable.

  In the general formula (III), the halogen atom represented by X may be any of a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, but is preferably a chlorine atom or a bromine atom. Further, as the hydrocarbon group having 1 to 20 carbon atoms represented by X, specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert- Linear or branched aliphatic hydrocarbon groups such as butyl group, neopentyl group, hexyl group and octyl group; aromatic hydrocarbon groups such as phenyl group, tolyl group and naphthyl group; aralkyl groups such as benzyl group And others: a hydrocarbon group containing a silicon atom such as a trimethylsilylmethyl group and a bistrimethylsilylmethyl group. Among them, a methyl group, an ethyl group, an isobutyl group, and a trimethylsilylmethyl group are preferable.

  In the general formula (III), X is preferably a bistrimethylsilylamide group or a hydrocarbon group having 1 to 20 carbon atoms.

In the general formula (III), [B] ^- The non-coordinating anion represented by, for example, a tetravalent boron anion. As the tetravalent boron anion, specifically, tetraphenyl borate, tetrakis (monofluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluorophenyl) borate, tetrakis ( (Pentafluorophenyl) borate, tetrakis (tetrafluoromethylphenyl) borate, tetra (tolyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl), phenyl] borate, tri Decahydride-7,8-dicarboundecaborate and the like can be mentioned, and among these, tetrakis (pentafluorophenyl) borate is preferable.

  The metallocene complex represented by the general formula (I) and the formula (II), and the half metallocene cation complex represented by the general formula (III) are further 0 to 3, preferably 0 to 1 neutral Lewis base L is included. Here, examples of the neutral Lewis base L include tetrahydrofuran, diethyl ether, dimethylaniline, trimethylphosphine, lithium chloride, neutral olefins, neutral diolefins, and the like. Here, when the complex contains a plurality of neutral Lewis bases L, the neutral Lewis bases L may be the same or different.

  Further, the metallocene complex represented by the general formula (I) and the formula (II), and the half metallocene cation complex represented by the general formula (III) may be present as a monomer, It may be present as a multimeric body or higher.

The metallocene complex represented by the general formula (I) may be, for example, a lanthanoid trishalide, scandium trishalide or yttrium trishalide in a solvent, an indenyl salt (eg, potassium salt or lithium salt) and bis (trialkylsilyl) It can be obtained by reacting with an amide salt (for example, potassium salt or lithium salt). Since the reaction temperature may be about room temperature, the reaction can be carried out under mild conditions. The reaction time is optional, but is about several hours to several tens of hours. The reaction solvent is not particularly limited, but is preferably a solvent that dissolves the raw materials and products, and for example, toluene may be used. Hereinafter, a reaction example for obtaining the metallocene complex represented by the general formula (I) will be described.
(In the formula, X ″ represents a halide.)

The metallocene complex represented by the above general formula (II) can be obtained, for example, by adding a lanthanoid trishalide, scandium trishalide or yttrium trishalide in a solvent to an indenyl salt (for example, potassium salt or lithium salt) and a silyl salt (for example, potassium). (A salt or a lithium salt). Since the reaction temperature may be about room temperature, the reaction can be carried out under mild conditions. The reaction time is optional, but is about several hours to several tens of hours. The reaction solvent is not particularly limited, but is preferably a solvent that dissolves the raw materials and products, and for example, toluene may be used. Hereinafter, a reaction example for obtaining the metallocene complex represented by the general formula (II) will be described.
(In the formula, X ″ represents a halide.)

The half metallocene cation complex represented by the general formula (III) can be obtained, for example, by the following reaction.

Here, in the compound represented by the general formula (IV), M represents a lanthanoid element, scandium or yttrium, and Cp ^R ′ each independently represents unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl. , X represents a hydrogen atom, a halogen atom, an alkoxide group, a thiolate group, an amide group, a silyl group or a hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, w represents 0 to 3 Indicates an integer. In general formula [A] ⁺ [B] ^- in the ionic compound represented by, [A] ⁺ represents a cation, [B] ^- is a non-coordinating anion.

Examples of the cation represented by [A] ⁺ include a carbonium cation, an oxonium cation, an amine cation, a phosphonium cation, a cycloheptatrienyl cation, and a ferrocenium cation having a transition metal. Examples of the carbonium cation include trisubstituted carbonium cations such as a triphenylcarbonium cation and a tri (substituted phenyl) carbonium cation.As the tri (substituted phenyl) carbonyl cation, specifically, tri (methylphenyl ) Carbonium cation and the like. Examples of the amine cation include trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tripropylammonium cation, and tributylammonium cation; N, N-dimethylanilinium cation, N, N-diethylanilinium cation, N, N- N, N-dialkylanilinium cations such as 2,4,6-pentamethylanilinium cation; dialkylammonium cations such as diisopropylammonium cation and dicyclohexylammonium cation; Examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation. Among these cations, an N, N-dialkylanilinium cation or a carbonium cation is preferable, and an N, N-dialkylanilinium cation is particularly preferable.

The general formula for the reaction [A] ⁺ [B] ^- As the ionic compound represented by a compound of a combination selected from each non-coordinating anion and cation of the, N, N-Jimechiruaniri Preference is given to ammonium tetrakis (pentafluorophenyl) borate, triphenylcarboniumtetrakis (pentafluorophenyl) borate and the like. In general formula [A] ⁺ [B] ^- ionic compounds represented by is preferably added from 0.1 to 10 mol per mol of the metallocene complex, more preferably it added about 1 molar. In the case where the half metallocene cation complex represented by the general formula (III) is used for the polymerization reaction, the half metallocene cation complex represented by the general formula (III) may be provided as it is in the polymerization reaction system, the compound represented by the general formula (IV) and the general formula used in the reaction [a] ⁺ [B] ^- provides an ionic compound represented separately into the polymerization reaction system, the general formula in the reaction system (III )) To form a half metallocene cation complex. Further, by using a metallocene complex represented by the general formula (I) or (II) in combination with an ionic compound represented by the general formula [A] ⁺ [B] ^- , A half metallocene cation complex represented by the formula (III) can also be formed.

  The structures of the metallocene complexes represented by the general formulas (I) and (II) and the half metallocene cation complex represented by the general formula (III) are preferably determined by X-ray structural analysis.

  The co-catalyst that can be used in the polymerization catalyst composition can be arbitrarily selected from components used as co-catalysts in a polymerization catalyst composition containing a usual metallocene complex. Preferred examples of the co-catalyst include aluminoxanes, organic aluminum compounds, and the above-mentioned ionic compounds. These cocatalysts may be used alone or in a combination of two or more.

  As the aluminoxane, an alkylaminoxan is preferable, and examples thereof include methylaluminoxane (MAO) and modified methylaluminoxane. Further, as the modified methylaluminoxane, MMAO-3A (manufactured by Tosoh Finechem Co., Ltd.) is preferable. The content of the aluminoxane in the polymerization catalyst composition is set so that the element ratio Al / M between the central metal M of the metallocene complex and the aluminum element Al of the aluminoxane is about 10 to 1000, preferably about 100. Is preferred.

  On the other hand, examples of the organoaluminum compound include trialkylaluminum, dialkylaluminum chloride, alkylaluminum dichloride, and dialkylaluminum hydride. Of these, trialkylaluminum is preferable. Examples of the trialkyl aluminum include triethyl aluminum, triisobutyl aluminum, and the like. The content of the organoaluminum compound in the polymerization catalyst composition is preferably 1 to 50 times, more preferably about 10 times, the mole of the metallocene complex.

--- Second polymerization catalyst composition--
Next, the second polymerization catalyst composition will be described in detail.
The second polymerization catalyst composition preferably contains the metallocene-based composite catalyst and a boron anion, and further contains other components contained in a catalyst composition containing a normal metallocene-based catalyst, such as a co-catalyst. More preferably. The metallocene composite catalyst and the boron anion are also referred to as a two-component catalyst. According to the second catalyst composition, a conjugated diene compound / non-conjugated olefin copolymer can be produced as in the case of the metallocene-based composite catalyst. It is possible to arbitrarily control the content of the monomer component in the copolymer.

  In the second polymerization catalyst composition, a specific example of the boron anion constituting the two-component catalyst is a tetravalent boron anion. For example, tetraphenylborate, tetrakis (monofluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluorophenyl) borate, tetrakis (pentafluorophenyl) borate, tetrakis (tetrafluoromethyl) Phenyl) borate, tetra (tolyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl), phenyl] borate, tridecahydride-7,8-dicarboundecaborate Among them, tetrakis (pentafluorophenyl) borate is preferable.

  The boron anion can be used as an ionic compound combined with a cation. Examples of the cation include a carbonium cation, an oxonium cation, an amine cation, a phosphonium cation, a cycloheptatrienyl cation, and a ferrocenium cation having a transition metal. Examples of the carbonium cation include trisubstituted carbonium cations such as a triphenylcarbonium cation and a tri (substituted phenyl) carbonium cation. As the tri (substituted phenyl) carbonyl cation, specifically, tri (methylphenyl) ) Carbonium cations and the like. Examples of the amine cation include trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tripropylammonium cation, and tributylammonium cation; N, N-dimethylanilinium cation, N, N-diethylanilinium cation, N, N- N, N-dialkylanilinium cations such as 2,4,6-pentamethylanilinium cation; dialkylammonium cations such as diisopropylammonium cation and dicyclohexylammonium cation; Examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation. Among these cations, an N, N-dialkylanilinium cation or a carbonium cation is preferable, and an N, N-dialkylanilinium cation is particularly preferable. Therefore, as the ionic compound, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, triphenylcarbonium tetrakis (pentafluorophenyl) borate and the like are preferable. The ionic compound comprising a boron anion and a cation is preferably added in an amount of 0.1 to 10 moles, more preferably about 1 mole, based on the metallocene composite catalyst.

--- Metallocene composite catalyst ---
Hereinafter, the metallocene composite catalyst will be described in detail.
The metallocene-based composite catalyst has a lanthanoid element, a rare earth element of scandium or yttrium, and a Group 13 element of the periodic table, and has the following formula (A):
_Ra MX _b QY _b ... (A)
[Wherein, R each independently represents unsubstituted or substituted indenyl, R is coordinated to M, M represents a lanthanoid element, scandium or yttrium, and X each independently represents a carbon number of 1 to 1. X is μ-coordinated to M and Q, Q is an element belonging to Group 13 of the periodic table, and Y is each independently a hydrocarbon group having 1 to 20 carbon atoms or A hydrogen atom, Y is coordinated to Q, and a and b are 2]. By using the metallocene-based polymerization catalyst, a copolymer of a conjugated diene compound and a non-conjugated olefin can be produced. In addition, by using the metallocene-based composite catalyst, for example, a catalyst previously combined with an aluminum catalyst, it becomes possible to reduce or eliminate the amount of alkylaluminum used in synthesizing the copolymer. When a conventional catalyst system is used, it is necessary to use a large amount of alkyl aluminum during the synthesis of the copolymer. For example, in a conventional catalyst system, it is necessary to use at least 10 equivalents of alkyl aluminum with respect to a metal catalyst. However, in the case of the above-mentioned metallocene composite catalyst, an excellent catalytic action can be obtained by adding about 5 equivalents of alkyl aluminum. Is exhibited.

  In the metallocene-based composite catalyst, the metal M in the formula (A) is a lanthanoid element, scandium, or yttrium. The lanthanoid elements include 15 elements having atomic numbers 57 to 71, and any of these elements may be used. Preferable examples of the metal M include samarium Sm, neodymium Nd, praseodymium Pr, gadolinium Gd, cerium Ce, holmium Ho, scandium Sc, and yttrium Y.

  In the formula (A), R is each independently unsubstituted indenyl or substituted indenyl, and R is coordinated to the metal M. Specific examples of the substituted indenyl group include, for example, 1,2,3-trimethylindenyl group, heptamethylindenyl group, 1,2,4,5,6,7-hexamethylindenyl group, and the like. Can be

  In the above formula (A), Q represents an element belonging to Group 13 of the periodic table, and specific examples include boron, aluminum, gallium, indium, and thallium.

  In the above formula (A), X each independently represents a hydrocarbon group having 1 to 20 carbon atoms, and X is μ-coordinated to M and Q. Here, as the hydrocarbon group having 1 to 20 carbon atoms, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group Pentadecyl group, hexadecyl group, heptadecyl group, stearyl group and the like. The μ-coordination is a coordination mode having a crosslinked structure.

  In the above formula (A), each Y independently represents a hydrocarbon group having 1 to 20 carbon atoms or a hydrogen atom, and the Y is coordinated to Q. Here, as the hydrocarbon group having 1 to 20 carbon atoms, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group Pentadecyl group, hexadecyl group, heptadecyl group, stearyl group and the like.

  As the metallocene-based composite catalyst, a metallocene-based composite catalyst represented by the above formula (I) is preferable.

--- Third polymerization catalyst composition--
Next, the third polymerization catalyst composition will be described.
The catalyst activity of the third polymerization catalyst composition is preferably 30 kg / mol · h or more, more preferably 1000 kg / mol · h or more. By setting the catalyst activity to 30 kg / mol · h or more, it becomes possible to efficiently synthesize polyisoprene. In addition, the numerical value of the catalyst activity here indicates the ability to produce polyisoprene per unit mole of catalyst and per unit time.
The third polymerization catalyst composition comprises at least a component (O): a rare earth element compound represented by the following general formula (i): M- (NQ ¹ ) (NQ ² ) (NQ ³ ) (i)
(Wherein M is at least one selected from lanthanoids, scandium and yttrium, and NQ ¹ , NQ ² and NQ ³ are amide groups, which may be the same or different, provided that MN Having a bond);
(P) component: at least one of an ionic compound (P-1) and a halogen compound (P-3);
Component (Q): The following general formula (X):
YR ¹ _a R ² _b R ³ _c ... (X)
(Wherein, Y is a metal selected from Group 1, Group 12, Group 12, and Group 13 of the periodic table, and R ¹ and R ² are a hydrocarbon group having 1 to 10 carbon atoms or hydrogen. R ³ is a hydrocarbon group having 1 to 10 carbon atoms, provided that R ¹ , R ² and R ³ may be the same or different from each other, and Y is a member of Group 1 of the periodic table. When a is a selected metal, a is 1 and b and c are 0, and when Y is a metal selected from Groups 2 and 12 of the periodic table, a and b are 1 and c is 0, and when Y is a metal selected from Group 13 of the periodic table, a, b and c are 1).
The component (O) is a reactant with a rare earth element compound Lewis base, and also includes a reactant having no bond between the rare earth element and carbon.
The above (P-1) includes an ionic compound composed of a non-coordinating anion and a cation.
The above (P-3) contains at least one of a Lewis acid, a complex compound of a metal halide and a Lewis base, and an organic compound containing an active halogen.
In addition, it may further contain aluminoxane (P-2).
Further, a compound (component (Q)) which can be an anionic ligand may be contained.

  In the above formula (i), examples of the amide group represented by NQ include an aliphatic amide group such as a dimethylamide group, a diethylamide group and a diisopropylamide group; a phenylamide group, a 2,6-di-tert-butylphenylamide group, 2,6-diisopropylphenylamide group, 2,6-dineobenylphenylamide group, 2-tert-butyl-6-isopropylphenylamide group, 2-tert-butyl-6-neobentylphenylamide group, 2- Any one of an arylamide group such as a 2,4,6-tert-butylphenylamide group and a bistrialkylsilylamide group such as a bistrimethylsilylamide group, and a bistrimethylsilylamide group Is preferred.

  In the polymerization reaction system, the molar amount of the component (O) contained in the third polymerization catalyst composition is preferably 1/5000 or less, particularly 1/10000 or less of the isoprene monomer added later. The specific concentration is preferably in the range of 0.1 to 0.0001 mol / l. By defining the molar ratio in this manner, the amount of cis-1,4 bond is improved, and the activity of the catalyst is improved. Therefore, the amount of the catalyst residue in the synthetic polyisoprene can be greatly reduced. Thereby, by blending the polyisoprene into the rubber composition, it is possible to further improve the durability.

  The component (O) used in the third polymerization catalyst composition is a rare earth element compound or a reaction product of the rare earth element compound and a Lewis base, wherein the rare earth element compound and the reaction product of the rare earth element compound and the Lewis base are used. Preferably, the reactant does not have a bond between the rare earth element and carbon. When the rare earth element compound and the reactant do not have a rare earth element-carbon bond, the compound is stable and easy to handle. Here, the rare earth element compound is a compound containing a lanthanoid element or scandium or yttrium composed of elements having atomic numbers 57 to 71 in the periodic table. Specific examples of the lanthanoid element include lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. The component (O) may be used alone or in a combination of two or more.

  In the component (O) used in the third polymerization catalyst composition, examples of the Lewis base that reacts with the rare earth element compound include tetrahydrofuran, diethyl ether, dimethylaniline, trimethylphosphine, lithium chloride, neutral olefins, And neutral diolefins.

  The component (P) used in the third polymerization catalyst composition is at least one compound selected from the group consisting of an ionic compound (P-1) and a halogen compound (P-3).

The ionic compound represented by the above (P-1) comprises a non-coordinating anion and a cation, and reacts with a rare earth element compound as the above component (O) or a reaction product thereof with a Lewis base to form a cationic compound. An ionic compound that can generate a transition metal compound can be used. Here, as the non-coordinating anion, a tetravalent boron anion, for example, tetraphenyl borate, tetrakis (monofluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluoroborate) Phenyl) borate, tetrakis (pentafluorophenyl) borate, tetrakis (tetrafluoromethylphenyl) borate, tetra (tolyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl) Phenyl] borate, and tridecahydride-7,8-dicarboundecaborate. Preferably, tetrakis (pentafluorophenyl) borate is used. On the other hand, examples of the cation include a carbonium cation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptatrienyl cation, and a ferrocenium cation having a transition metal. Specific examples of the carbonium cation include a trisubstituted carbonium cation such as a triphenylcarbonium cation and a tri (substituted phenyl) carbonium cation. As the tri (substituted phenyl) carbonyl cation, more specifically, Tri (methylphenyl) carbonium cation, tri (dimethylphenyl) carbonium cation, and the like. Specific examples of the ammonium cation include trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tripropylammonium cation, and tributylammonium cation (for example, tri (n-butyl) ammonium cation); N, N-dimethylanilinium N, N-dialkylanilinium cations such as cation, N, N-diethylanilinium cation, N, N-2,4,6-pentamethylanilinium cation; dialkylammonium cations such as diisopropylammonium cation and dicyclohexylammonium cation Is mentioned. Specific examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation. Therefore, as the ionic compound, a compound selected and combined from the above-mentioned non-coordinating anions and cations is preferable. Specifically, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, triphenylcarboate Preference is given to potassium tetrakis (pentafluorophenyl) borate. In addition, these ionic compounds can be used alone or in combination of two or more. The content of the ionic compound in the third polymerization catalyst composition is preferably 0.1 to 10 moles, more preferably about 1 mole, relative to the component (O).

  The aluminoxane represented by the above (P-2) is a compound obtained by bringing an organoaluminum compound into contact with a condensing agent, and is, for example, a repeating unit represented by the general formula: (-Al (R ') O-) A chain aluminoxane or a cyclic aluminoxane having a unit (wherein R ′ is a hydrocarbon group having 1 to 10 carbon atoms, and some of the hydrocarbon groups may be substituted with a halogen atom and / or an alkoxy group; The degree of polymerization of the unit is preferably 5 or more, and more preferably 10 or more). Here, specific examples of R ′ include a methyl group, an ethyl group, a propyl group, an isobutyl group and the like, and among these, a methyl group is preferable. Examples of the organoaluminum compound used as a raw material of the aluminoxane include trialkylaluminums such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, and mixtures thereof, with trimethylaluminum being particularly preferred. For example, an aluminoxane using a mixture of trimethylaluminum and tributylaluminum as a raw material can be suitably used. The content of the aluminoxane in the third polymerization catalyst composition is such that the element ratio Al / M of the rare earth element M constituting the component (O) to the aluminum element Al of the aluminoxane is about 10 to 1,000. Is preferable.

  The halogen compound represented by the above (P-3) contains at least one of a Lewis acid, a complex compound of a metal halide and a Lewis base, and an organic compound containing an active halogen, and is, for example, the above (O) component. By reacting with a rare earth element compound or a reaction product thereof with a Lewis base, a cationic transition metal compound, a halogenated transition metal compound, or a compound having a transition metal center with insufficient charge can be produced. The total content of the halogen compound in the third polymerization catalyst composition is preferably 1 to 5 times the mole of the component (O).

As the Lewis acid, a boron-containing halogen compound such as B (C ₆ F ₅ ) _{3 and} an aluminum-containing halogen compound such as Al (C ₆ F ₅ ) ₃ can be used. A halogen compound containing an element belonging to Group V, VI or VIII can also be used. Preferably, an aluminum halide or an organic metal halide is used. Further, as the halogen element, chlorine or bromine is preferable. As the Lewis acid, specifically, methyl aluminum dibromide, methyl aluminum dichloride, ethyl aluminum dibromide, ethyl aluminum dichloride, butyl aluminum dibromide, butyl aluminum dichloride, dimethyl aluminum bromide, dimethyl aluminum chloride, diethyl aluminum bromide, diethyl Aluminum chloride, dibutyl aluminum bromide, dibutyl aluminum chloride, methyl aluminum sesquibromide, methyl aluminum sesquichloride, ethyl aluminum sesquibromide, ethyl aluminum sesquichloride, dibutyl tin dichloride, aluminum tribromide, antimony trichloride, antimony pentachloride, phosphorus trichloride , Pentachloride , Tin tetrachloride, titanium tetrachloride, tungsten hexachloride, etc., among which diethyl aluminum chloride, ethyl aluminum sesquichloride, ethyl aluminum dichloride, diethyl aluminum bromide, ethyl aluminum sesquibromide, ethyl aluminum dibromide are particularly preferred. preferable.

  Examples of the metal halide constituting the complex compound of the metal halide and the Lewis base include beryllium chloride, beryllium bromide, beryllium iodide, magnesium chloride, magnesium bromide, magnesium iodide, calcium chloride, calcium bromide, and iodine. Calcium iodide, barium chloride, barium bromide, barium iodide, zinc chloride, zinc bromide, zinc iodide, cadmium chloride, cadmium bromide, cadmium iodide, mercury chloride, mercury bromide, mercury iodide, manganese chloride, Manganese bromide, manganese iodide, rhenium chloride, rhenium bromide, rhenium iodide, copper chloride, copper iodide, silver chloride, silver bromide, silver iodide, gold chloride, gold iodide, gold bromide, etc. Of these, magnesium chloride, calcium chloride, barium chloride, manganese chloride, zinc chloride and copper chloride are preferred. , Magnesium chloride, manganese chloride, zinc chloride, copper chloride being particularly preferred.

As the Lewis base constituting the complex compound of the metal halide and the Lewis base, a phosphorus compound, a carbonyl compound, a nitrogen compound, an ether compound, an alcohol and the like are preferable. Specifically, tributyl phosphate, tri-2-ethylhexyl phosphate, triphenyl phosphate, tricresyl phosphate, triethylphosphine, tributylphosphine, triphenylphosphine, diethylphosphinoethane, diphenylphosphinoethane, acetylacetone, benzoylacetone , Propionitrile acetone, valeryl acetone, ethyl acetylacetone, methyl acetoacetate, ethyl acetoacetate, phenyl acetoacetate, dimethyl malonate, diethyl malonate, diphenyl malonate, acetic acid, octanoic acid, 2-ethylhexanoic acid, oleic acid , Stearic acid, benzoic acid, naphthenic acid, versatic acid, triethylamine, N, N-dimethylacetamide, tetrahydrofuran, diphenyl ether, 2-ethylhexyl alcohol, Ilyl alcohol, stearyl alcohol, phenol, benzyl alcohol, 1-decanol, lauryl alcohol and the like. Among them, tri-2-ethylhexyl phosphate, tricresyl phosphate, acetylacetone, 2-ethylhexanoic acid, versatic acid, -Ethylhexyl alcohol, 1-decanol,
Lauryl alcohol is preferred.

  The Lewis base is reacted at a rate of 0.01 to 30 mol, preferably 0.5 to 10 mol, per 1 mol of the metal halide. The use of a reaction product with this Lewis base can reduce the amount of metal remaining in the polymer.

  Examples of the organic compound containing an active halogen include benzyl chloride and the like.

The component (Q) used in the third polymerization catalyst composition is represented by the following general formula (X):
YR ¹ _a R ² _b R ³ _c ... (X)
(Wherein, Y is a metal selected from Group 1, Group 2, Group 12 and Group 13 of the periodic table, and R ¹ and R ² are the same or different and have 1 to 10 carbon atoms. A hydrocarbon group or a hydrogen atom, wherein R ³ is a hydrocarbon group having 1 to 10 carbon atoms, provided that R ³ may be the same as or different from R ¹ or R ^2, and Y is a periodic table When a is a metal selected from Group 1, a is 1 and b and c are 0, and when Y is a metal selected from Group 2 and Group 12 of the periodic table, a and b are 1 and c is 0, and when Y is a metal selected from Group 13 of the periodic table, a, b and c are 1). And the following general formula (Xa):
AlR ¹ R ² R ³ ... (Xa)
(Wherein, R ¹ and R ² are the same or different and are a hydrocarbon group or a hydrogen atom having 1 to 10 carbon atoms, and R ³ is a hydrocarbon group having 1 to 10 carbon atoms, provided that R ³ is It may be the same or different from R ¹ or R ² ). Examples of the organoaluminum compound of the general formula (Xa) include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-t-butylaluminum, tripentylaluminum. , Trihexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum; diethyl aluminum hydride, di-n-propyl aluminum hydride, di-n-butyl aluminum hydride, diisobutyl aluminum hydride, dihexyl aluminum hydride, diiso aluminum hydride Hexyl aluminum, dioctyl aluminum hydride, diisooctyl aluminum hydride; ethyl aluminum dihydride, n-propyl aluminum Um dihydride, it includes isobutyl aluminum dihydride and the like, among these, triethylaluminum, triisobutylaluminum, hydrogenated diethylaluminum, hydrogenated diisobutylaluminum are preferred. The organoaluminum compound as the component (Q) described above can be used alone or in combination of two or more. The content of the component (Q) in the third polymerization catalyst composition is preferably at least 10 times, more preferably at least 20 to 1000 times the mole of the component (O). The content of the component (Q) is preferably 1/5000 or more, more preferably 1/3000 to 1/10, of the molar amount of the isoprene monomer to be added later. By defining the molar ratio in this manner, the amount of cis-1,4 bond is improved, and the activity of the catalyst is improved. Therefore, the amount of the catalyst residue in the synthetic polyisoprene can be greatly reduced. Thereby, by blending the polyisoprene into the rubber composition, it is possible to further improve the durability.

--- Compound that can be an anionic ligand ----
The compound that can be an anionic ligand (component (R)) is not particularly limited as long as it can be exchanged with the amide group of component (O), and has any of an OH group, an NH group, and an SH group. Is preferred.

Specific compounds having an OH group include aliphatic alcohols and aromatic alcohols. Specifically, dibutylhydroxytoluene, alkylated phenol, 4,4'-thiobis- (6-t-butyl-3-methylphenol), 4,4'-butylidenebis- (6-t-butyl-3-methylphenol) ), 2,2'-methylenebis- (4-methyl-6-t-butylphenol), 2,2'-methylenebis- (4-ethyl-6-t-butylphenol), 2,6-di-t-4- Ethylphenol, 1,1,3-tris- (2-methyl-4-hydroxy-5-t-butylphenyl) butane, n-octadecyl-3- (4-hydroxy-3,5-di-t-butylphenyl ) Propionate, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, dilaurylthiodipropionate, disteary Examples thereof include, but are not limited to, luthiodipropionate and dimyristylylthiopropionate. For example, as a hindered phenol compound, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3 , 5-Di-t-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3 , 5-triazine, pentaerythryl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thio-diethylenebis [3- (3,5-di- t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, N, N'- Hexamethylene bis (3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), 3,5-t-butyl-4-hydroxybenzyl fosphonate-diethyl ester, 1,3,5- Trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, octyl Diphenylamine, 2,4-bis [(octylthio) methyl] -o-cresol and the like. As the hydrazine-based compound, N, N'-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine can be exemplified.

  Examples of those having an NH group include primary amines and secondary amines such as alkylamines and arylamines. Specific examples include dimethylamine, diethylamine, pyrrole, ethanolamine, diethanolamine, dicyclohexylamine, N, N'-dibenzylethylenediamine, bis (2-diphenylphosphinophenyl) amine, and the like.

  Examples of the compound having an SH group include compounds represented by the following general formulas (VI) and (VII) in addition to aliphatic thiols and aromatic thiols.

(Wherein, R ¹ , R ² and R ³ are each independently —O—C _j H _{2j + 1} , — (O—C _k H _2k −) _a —O—C _m H _{2m + 1} or —C _n H _{2n + 1} , wherein at least one of R ¹ , R ² and R ³ is — (O—C _k H _2k −) _a —O—C _m H _{2m + 1} , and j, m and n are Each independently is 0 to 12, k and a are each independently 1 to 12, R ⁴ has 1 to 12 carbon atoms, and is a linear, branched or cyclic, saturated or unsaturated; , An alkylene group, a cycloalkylene group, a cycloalkylalkylene group, a cycloalkenylalkylene group, an alkenylene group, a cycloalkenylene group, a cycloalkylalkenylene group, a cycloalkenylalkenylene group, an arylene group or an aralkylene group.) In the general formula (VI) As a specific example of what is shown, 3-mercaptopropion Trimethoxysilane, 3-mercaptopropyl triethoxy silane, 3-mercaptopropyl methyl dimethoxy silane, (mercaptomethyl) dimethylethoxysilane, (mercaptomethyl) dimethylethoxysilane include mercaptomethyl trimethoxysilane.

(Wherein, W is -NR ⁸ -, - O- or -CR ⁹ R ¹⁰ - (wherein, R ⁸ and R ⁹ are _{-C p H 2p + 1, R} 10 is -C _q H _{2q +} is _1, p and q are 0 to 20 independently) is represented by, R ⁵ and R ⁶ are independently _{-M-C r H 2r -.} ( where, M is -O- Or —CH ₂ —, and r is 1 to 20), and R ⁷ is —O—C _j H _{2j + 1} , — (O—C _k H _2k —) _a —O—C _m. H _{2m + 1} or —C _n H _{2n + 1} , j, m and n are each independently 0 to 12, k and a each independently 1 to 12, R ⁴ is carbon A linear, branched or cyclic, saturated or unsaturated alkylene group, cycloalkylene group, cycloalkylalkylene group, cycloalkenylalkylene group, alkenylene group, cycloalkene Down group, a cycloalkyl alkenylene group, cycloalkenyl alkenylene group, an arylene group or an aralkylene group.)
Specific examples of the compound represented by the general formula (VII) include 3-mercaptopropyl (ethoxy) -1,3-dioxa-6-methylaza-2-silacyclooctane and 3-mercaptopropyl (ethoxy) -1,3-dioxa -6-butylaza-2-silacyclooctane, 3-mercaptopropyl (ethoxy) -1,3-dioxa-6-dodecylaza-2-silacyclooctane, and the like.

As the component (R), an anionic tridentate ligand precursor represented by the following general formula (ii) can be preferably used.
E ¹ −T ¹ −X−T ² −E ² (ii)
(R represents an anionic electron donating group containing a coordinating atom selected from Group 15 atoms, and E ¹ and E ² each independently represent a coordinating atom selected from Group 15 and Group 16 atoms. And T ¹ and T ² each represent a crosslinking group that bridges X with E ¹ and ~ E ^2.

  The component (R) is preferably added in an amount of 0.01 to 10 mol, particularly 0.1 to 1.2 mol, per 1 mol of the rare earth element compound ((O) component). When the addition amount is 0.1 mol or more, the catalyst activity becomes sufficiently high, and it becomes possible to efficiently synthesize polyisoprene. It is preferable that the addition amount is equivalent to the rare-earth element compounding barrier (1.0 mol), but an excessive amount may be added. However, if the addition amount exceeds 1.2 mol, the loss of the reagent is large, which is not preferable.

In the general formula (ii), the neutral electron donating groups E ¹ and E ² are groups containing a coordination atom selected from Group 15 and Group 16. E ¹ and E ² may be the same group or different groups. Examples of the coordinating atom include nitrogen N, phosphorus P, oxygen O, sulfur S and the like, and P is preferable.

When the coordinating atom contained in E ¹ and E ² is P, the neutral electron donating group E ¹ or E ² may be 1) a diarylphosphino group or a ditolylphosphino group; A finino group, 2) a dialkylphosphino group such as a dimethylphosphino group or a diethylphosphino group, and 3) an alkylarylphosphino group such as a methylphenylphosphino group, more preferably a diarylphosphino group. .

When the coordinating atom contained in E ¹ and E ² is N, the neutral electron donating group E ¹ or E ² may be 1) a dimethylamino group, a diethylamino group, a bis (trimethylsilyl) amino group, or the like. 2) diarylamino group such as diphenylamino group, and 3) alkylarylamino group such as methylphenyl group.

When the coordinating atom contained in the above E ¹ and E ² is O, the neutral electron donating group E ¹ or E ² may be 1) an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group or a butoxy group. And 2) an aryloxy group such as a phenoxy group and a 2,6-dimethylphenoxy group.

When the coordinating atom contained in E ¹ and E ² is S, the neutral electron donating group E ¹ or E ² may be 1) an alkylthio group such as a methylthio group, an ethylthio group, a propylthio group, or a butylthio group. And 2) an arylthio group such as a phenylthio group and a tolylthio group.

  The anionic electron donating group X is a group containing a coordination atom selected from Group 15. The coordinating atom is preferably phosphorus P or nitrogen N, and more preferably N.

The crosslinking groups T ¹ and T ² may be any groups capable of crosslinking X with E ¹ and E ² , and examples thereof include an arylene group which may have a substituent on the aryl ring. T ¹ and T ² may be the same or different groups.
The arylene group may be a phenylene group, a naphthylene group, a pyridylene group, a thienylene group (preferably, a phenylene group or a naphthylene group). Further, an arbitrary group may be substituted on the aryl ring of the arylene group. Examples of the substituent include an alkyl group such as a methyl group and an ethyl group, an aryl group such as a phenyl group and a tolyl group, a halogen group such as fluoro, chloro and bromo, and a silyl group such as a trimethylsilyl group.
As the arylene group, a 1,2-phenylene group is more preferably exemplified.

  Preferred examples of the anionic tridentate ligand precursor in the metal complex constituting the third polymerization catalyst composition include those represented by the following general formula (iii). These can be produced, for example, by referring to the methods described in the following Examples, or Organometallics, 23, p 47784787 (2004).

(In the above formula, R represents an alkyl group or an aryl group, Y represents hydrogen, an alkyl group, a halogeno group, a silyl group, or the like.)
More specifically, PNP ligands such as bis (2-diphenylphosphinophenyl) amine are exemplified.

--- Fourth polymerization catalyst composition-
Next, the fourth polymerization catalyst composition will be described.
The catalyst activity of the fourth polymerization catalyst composition is the same as that of the third polymerization catalyst composition except that the following component (P-2) is used in place of the component (P) in the polymerization catalyst composition. It is the same as the polymerization catalyst composition.
Component (P-2): a hydrocarbylaluminoxane compound having a hydrocarbon group having 1 to 20 carbon atoms

  The component (P-2) used in the fourth polymerization catalyst composition is a hydrocarbylaluminoxane compound having a hydrocarbon group having 1 to 20 carbon atoms.

The hydrocarbylaluminoxane compound is preferably an alkylaluminoxane, and examples of the alkylaluminoxane include methylaluminoxane (MAO), modified methylaluminoxane, and the like. Preferable examples of the modified methylaluminoxane include P-MAO and MMAO-3A (manufactured by Tosoh Finechem).
The content of the component (P-2) in the fourth polymerization catalyst composition is preferably at least 10 times the mole of the component (O).

-Conjugated diene monomer-
The conjugated diene monomer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include 1,3-butadiene, isoprene, 1,3-pentadiene, 2-ethyl-1,3-butadiene, , 3-dimethylbutadiene (2,3-dimethyl-1,3-butadiene), 2-methylpentadiene, 4-methylpentadiene, 2,4-hexadiene, 1,3-hexadiene, and the like. These may be used alone or in combination of two or more.
Among these, 1,3-butadiene and isoprene are preferable from the viewpoint of improving various properties of a rubber composition, a rubber product, and the like.

-Polar monomer-
The polar monomer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, and (meth) acrylic acid. n-propyl, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, (meth) ) (Meth) acrylic monomers such as n-pentyl acrylate, n-hexyl (meth) acrylate, and cyclohexyl (meth) acrylate; acrylonitrile monomers such as acrylonitrile and methacrylonitrile; These may be used alone or in combination of two or more.
Among them, methyl (meth) acrylate and acrylonitrile are preferable from the viewpoint that the physical properties of the nonpolar rubber can be improved and, for example, the adhesion of the polymer and the breaking strength of the polymer can be improved.
In this specification, “(meth) acrylic acid” represents at least one of “acrylic acid” and “methacrylic acid”, and “(meth) acrylic” refers to “acrylic” and “methacrylic”. Methacrylic ".

  Here, the molar amount of the component (A) with respect to a total of 100 g of the conjugated diene monomer and the polar monomer is preferably 0.01 mmol or more, more preferably 0.03 mmol or more, from the viewpoint of sufficiently obtaining the catalytic activity. From the viewpoint of preventing excess, the amount is preferably 0.5 mmol or less, more preferably 0.05 mmol or less.

  The solvent used in the polymerization reaction step is not particularly limited as long as it is inert in the polymerization reaction, and can be appropriately selected depending on the intended purpose.Examples include n-hexane, cyclohexane, and mixtures thereof. Is mentioned. Here, highly toxic aromatic hydrocarbons (benzene, toluene, xylene, etc.) are not required.

In the above polymerization reaction step, a well-known method in the technical field such as a solution polymerization method, a suspension polymerization method, a liquid phase bulk polymerization method, an emulsion polymerization method, a gas phase polymerization method, and a solid phase polymerization method can be used.
The reaction temperature in the polymerization reaction step is not particularly limited and may be appropriately selected depending on the purpose. However, it is preferably -100 to 300 ° C, more preferably 0 to 200 ° C, and particularly preferably 25 to 120 ° C. . At a high temperature, the cis-1,4-selectivity may decrease, and at a low temperature, the reaction rate may decrease.
The reaction pressure in the polymerization reaction step is not particularly limited and can be appropriately selected depending on the purpose. For example, the pressure can be normal pressure. At a high pressure, the monomer (monomer) may not be sufficiently taken into the polymerization reaction system, and at a low pressure, the reaction rate may decrease.
The reaction time in the polymerization reaction step is not particularly limited and can be appropriately selected depending on the purpose, and can be, for example, 0.5 to 3 hours.

<Monomer preparation step>
The monomer preparation step is a step of preparing the conjugated diene monomer and the polar monomer described above as a monomer.

<Catalyst preparation step>
The catalyst system preparation step is a step of preparing a polymerization catalyst composition (predetermined polymerization catalyst composition) containing the above-mentioned rare earth element compound and the above-mentioned compound having a cyclopentadiene skeleton.

The reagent used in each of the above steps (polymerization reaction step, monomer preparation step, catalyst system preparation step) may be used without a solvent or together with a solvent suitable for each reagent.
In each of the above steps, the reagent and the solvent are preferably used after appropriately performing purification operations such as distillation, degassing, and freeze-drying.
Further, it is preferable that each of the above steps, in particular, the catalyst system preparation step and the polymerization reaction step be performed in an atmosphere of an inert gas such as nitrogen gas or argon gas.

  The method for producing the copolymer of the present invention is not limited to the above-described production method.For example, in the production method of the above-described example, a compound having a cyclopentadiene skeleton may be used in a catalyst system preparation step in a polymerization catalyst composition. May be added in the polymerization reaction step.

(Copolymer)
The copolymer of one example of the present invention (hereinafter, also referred to as “one example of a copolymer”) is produced by the method for producing a copolymer of one example of the present invention.
According to the conjugated diene-derived portion in one example of the copolymer, since it has an extremely high cis-1,4-bond content, a copolymer having high elasticity can be provided and used as a rubber component in a rubber composition. Can be.

The molar ratio of the component derived from the polar monomer (the portion derived from the polar monomer) to the sum of the component derived from the polar monomer (the portion derived from the polar monomer) and the component derived from the conjugated diene (the portion derived from the conjugated diene) Although the ratio of each component can be freely combined, the ratio is preferably 20 mol% or less, more preferably 2 mol% to 15 mol%, in order to maintain the physical properties of the rubber depending on the application.
The cis-1,4-bond content of the conjugated diene-derived portion in the copolymer is not particularly limited and can be appropriately selected depending on the purpose. The content is preferably 95% or more, more preferably 97% or more. 98% or more is particularly preferable. As the cis-1,4-bond content of the conjugated diene-derived portion in the copolymer becomes higher, the elongation crystallinity of the copolymer can be increased and the elasticity of the copolymer can be increased. .
The trans-1,4-bond content of the conjugated diene-derived portion in the copolymer is not particularly limited and may be appropriately selected depending on the purpose. The content is preferably less than 5%, more preferably less than 3%, Less than 1% is particularly preferred. The lower the trans-1,4-bond content of the conjugated diene-derived portion in the copolymer, the higher the elongation crystallinity of the copolymer and the higher the elasticity of the copolymer. .
The 1,2-vinyl bond content of the conjugated diene-derived portion in the copolymer is not particularly limited and may be appropriately selected depending on the intended purpose, and is preferably 5% or less, more preferably 3% or less, and 1% or less. % Or less is particularly preferred. The lower the 1,2-vinyl bond content of the conjugated diene-derived portion in the copolymer, the higher the elongation crystallinity of the copolymer and the higher the elasticity of the copolymer.
The 3,4-vinyl bond content of the conjugated diene-derived portion in the above copolymer is not particularly limited and can be appropriately selected depending on the purpose, and is preferably 5% or less, more preferably 3% or less, and 1% or less. % Or less is particularly preferred. The lower the 3,4-vinyl bond content of the conjugated diene-derived portion in the copolymer, the higher the elongation crystallinity of the copolymer and the higher the elasticity of the copolymer.

The number average molecular weight (Mn) of the copolymer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 300,000 or more, more preferably 400,000 or more.
The molecular weight distribution (Mw / Mn) of the copolymer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 3.0 or less, more preferably 2.5 or less.

  The type of the copolymer is not particularly limited and can be appropriately selected depending on the intended purpose.However, one type of a block copolymer, an alternating copolymer, a graph and a copolymer, and a random copolymer is used. The above is obtained. Although not limited thereto, it can be confirmed by using, for example, 1H-MNR and 13C-NMR.

<Chain structure of copolymer>
To confirm the formation of the block copolymer, differential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR) are used as main measuring means. The differential scanning calorimetry (DSC) is a measurement method performed in accordance with JIS K 7121-1987. Specifically, when the glass transition temperature derived from the portion composed of the conjugated diene monomer unit, the crystallization temperature derived from the portion, and the crystallization temperature derived from the portion composed of the polar monomer unit can be observed by DSC, if both can be observed, This indicates that a block portion composed of a conjugated diene monomer unit and a portion composed of a polar monomer unit are formed in the polymer.

(Rubber composition)
The rubber composition of one example of the present invention (hereinafter, also referred to as “one rubber composition”) needs to include the copolymer of one example of the present invention. Here, the copolymer of one example of the present invention can be a rubber component.
One example of the rubber composition may include a rubber component other than the above-described one example of the copolymer, and may also include a filler, an antioxidant, a softener, stearic acid, zinc white, a vulcanization accelerator, a vulcanizing agent, and an oil. , Sulfur, and the like.
One example rubber composition can be manufactured by methods well known to those skilled in the art.

(Rubber product)
The rubber product of one example of the present invention (hereinafter, also referred to as “one rubber product”) needs to be manufactured using the rubber composition of one example of the present invention. Examples of rubber products include, for example, tire members such as treads, base treads, sidewalls, side reinforcing rubbers, and bead fillers; other automobile parts; Industrial goods such as hoses; sports goods; footwear; toys; thread rubbers; adhesives;

<Tire>
All members of the tire can be manufactured using one example of the rubber composition.
The tire can be manufactured by a method well known to those skilled in the art.

  Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

(Production of copolymer)
A copolymer was produced according to the following.
(Example 1)
286 g of a hexane solution containing 60 g (0.88 mol) of isoprene (conjugated diene monomer) was added to a sufficiently dried 2 L stainless steel reactor.
On the other hand, in a glove box under a nitrogen atmosphere, 50 μmol of trisbistrimethylsilylamide gadolinium (Gd [N (SiMe ₃ ) ₂ ] ₃ ) (component (A)) and 2-phenylindene (component (B)) were placed in a glass container. ) 100 μmol and 2.5 mmol of diisobutylaluminum hydride (component (C)) were added, and these were dissolved in 5 mL of hexane. Then, in this glass container, MMAO (manufactured by Tosoh Finechem Co., Ltd., product name: MMAO-3A) (component (D)) was added to the ratio of the moles of aluminum in MMAO to gadolinium in trisbistrimethylsilylamide gadolinium. The amount was increased to 600 times, and 100 μmol of diethyl aluminum chloride (component (E-1)) was further added to obtain a polymerization catalyst composition.
Thereafter, the polymerization catalyst composition was taken out of the glove box, and an amount of the polymerization catalyst composition containing 8.1 μmol of gadolinium was added to a 2 L reactor containing isoprene. This reaction system was maintained at 50 ° C. for 90 minutes, after which 8.4 g (0.1 mol) of methyl acrylate (a polar monomer) was charged and maintained at 50 ° C. for 90 minutes to perform a copolymerization reaction. Thereafter, 5 mL of an isopropanol solution (5% by mass) of 2,2′-methylene-bis (6-t-butyl-4-ethylphenol) (manufactured by Ouchi Shinko Chemical Co., Ltd., product name: Nocrack NS-5) was added to The copolymerization reaction was stopped by adding to the reaction system. Further, the reaction product was precipitated and separated by adding a large amount of methanol to the reactor, and further dried in vacuum at 60 ° C. to obtain a copolymer A (yield: 60 g).
No aromatic hydrocarbons (such as toluene) were used throughout the above production.

(Example 2)
A polymerization catalyst composition was prepared and a copolymerization reaction was carried out in the same manner as in Example 1 except that 3-benzylindene was used instead of 2-phenylindene, to obtain a copolymer B (yield: 60 g).

(Example 3)
A polymerization catalyst composition was prepared and a copolymerization reaction was carried out in the same manner as in Example 1 except that indene was used instead of 2-phenylindene, to obtain a copolymer C (yield: 58 g).

(Example 3-2)
Preparation of the polymerization catalyst composition and copolymerization reaction in the same manner as in Example 1 except that "acrylonitrile was used instead of methyl acrylate" and "tetramethylcyclopentadiene was used instead of 2-phenylindene". Was carried out to obtain a copolymer C-2 (yield: 60 g).

(Comparative Example 1)
"The point where 2-phenylindene was not used", "The point where N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate [Me ₂ NHPhB (C ₆ F ₅ ) ₄ ] was used instead of MMAO”, and A polymerization catalyst composition was prepared and a copolymerization reaction was carried out in the same manner as in Example 1 except that "toluene was used instead of hexane" to obtain a copolymer D (yield: 55 g).

(Comparative Example 2)
“A point where bis (2-phenylindenyl) gadolinium bis (dimethylsilylamide) ((2-PhC ₉ H ₆ ) ₂ GdN (SiHMe ₂ ) ₂ ) (metallocene catalyst) was used in place of trisbistrimethylsilylamide gadolinium” , "Point not using _2- phenylindene", "Point using N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate [Me ₂ NHPhB (C ₆ F ₅ ) ₄ ] instead of MMAO”, A polymerization catalyst composition was prepared and a copolymerization reaction was carried out in the same manner as in Example 1 except for the point that "toluene was used instead of hexane", to obtain a copolymer E (yield: 58 g).

(Example 4)
260 g of a hexane solution containing 60 g (1.11 mol) of 1,3-butadiene (conjugated diene monomer) was added to a sufficiently dried stainless steel 2 L reactor.
On the other hand, in a glove box under a nitrogen atmosphere, trisbistrimethylsilylamido gadolinium (Gd [N (SiMe ₃ ) ₂ ] ₃ ) (component (A)) (200 μm) and trimethylsilylfluorene (component (B)) 400 μmol were placed in a glass container. 20.0 mmol of diisobutylaluminum hydride (component (C)) was added, and these were dissolved in 80 mL of hexane. Then, in this glass container, MMAO (manufactured by Tosoh Finechem Co., Ltd., product name: MMAO-3A) (component (D)) was added to the ratio of the moles of aluminum in MMAO to gadolinium in trisbistrimethylsilylamide gadolinium. As a 600-fold amount, 400 μmol of diethyl aluminum chloride (component (E-1)) was further added to obtain a polymerization catalyst composition.
Thereafter, the polymerization catalyst composition was taken out of the glove box, and an amount of the polymerization catalyst composition containing 14 μmol of gadolinium was added to a 2 L reactor containing 1,3-butadiene. This reaction system was maintained at 50 ° C. for 90 minutes, after which 8.4 g (0.1 mol) of methyl acrylate (a polar monomer) was charged and maintained at 50 ° C. for 90 minutes to perform a copolymerization reaction. Thereafter, 5 mL of an isopropanol solution (5% by mass) of 2,2′-methylene-bis (6-t-butyl-4-ethylphenol) (manufactured by Ouchi Shinko Chemical Co., Ltd., product name: Nocrack NS-5) was added to The copolymerization reaction was stopped by adding to the reaction system. Further, the reaction product was precipitated and separated by adding a large amount of methanol to the reactor, and further dried in vacuum at 60 ° C. to obtain a copolymer F (yield: 60 g).
No aromatic hydrocarbons (such as toluene) were used throughout the above production.

(Example 5)
The polymerization catalyst was the same as in Example 4, except that "3-benzylindene was used instead of trimethylsilylfluorene" and "TMAO (manufactured by Tosoh Fine Chemical Co., Ltd., product name: TMAO341) was used instead of MMAO". Preparation of the composition and a copolymerization reaction were performed to obtain a copolymer G (yield: 60 g).

(Example 6)
A polymerization catalyst composition was prepared and a copolymerization reaction was carried out in the same manner as in Example 4 except that 2-phenylindene was used instead of trimethylsilylfluorene, to obtain a copolymer H (yield: 60 g).

(Example 7)
"Tris bistrimethylsilylamide gadolinium _{(Gd [N (SiMe 3)} 2] 3) instead of tris tert- blanking of butoxide gadolinium (Gd (OtBu) ₃₎ points with" and "instead of 3-methyl-trimethylsilyl fluorene -2 Preparation of a polymerization catalyst composition and a copolymerization reaction were carried out in the same manner as in Example 4 except for "a point using -phenylindene" to obtain a copolymer I (yield: 60 g).

(Example 8)
A polymerization catalyst composition was prepared and a copolymerization reaction was carried out in the same manner as in Example 4 except that 3-benzyl-2-phenylindene was used instead of trimethylsilylfluorene to obtain a copolymer J (yield: 50 g). .

(Example 9)
Implementation than "in place of tris bistrimethylsilylamide gadolinium _{(Gd [N (SiMe 3)} 2] 3), (Gd (StBu) 3) points with" and "point using indene instead of trimethylsilyl fluorene" A polymerization catalyst composition was prepared and a copolymerization reaction was carried out in the same manner as in Example 4 to obtain a copolymer K (yield: 58 g).

(Comparative Example 3)
A copolymerization reaction was carried out in the same manner as in Example 4 except that trimethylsilylfluorene was not used, and a copolymer L was obtained (yield: 55 g).

(Example 10)
The polymerization catalyst was the same as in Example 4, except that "5.2 g of acrylonitrile was used instead of 8.4 g of methyl acrylate" and "3-benzyl-2-phenylindene was used instead of trimethylsilylfluorene". Preparation of the composition and a copolymerization reaction were performed to obtain a copolymer M (yield: 60 g).

(Example 11)
260 g of a hexane solution containing 60 g (1.11 mol) of 1,3-butadiene (conjugated diene monomer) was added to a sufficiently dried stainless steel 2 L reactor.
On the other hand, in a glove box under a nitrogen atmosphere, 200 μmol of trisbistrimethylsilylamide gadolinium (Gd [N (SiMe ₃ ) ₂ ] ₃ ) ((A) component) and 3-benzylindene ((B) component) were placed in a glass container. ) 400 μmol and 20.0 mmol of diisobutylaluminum hydride (component (C)) were added, and these were dissolved in 80 mL of hexane. Then, in this glass container, TMAO (manufactured by Tosoh Fine Chemicals Co., Ltd., product name: TMAO341) (component (D)) was added at a ratio 300 times the molar ratio of aluminum in TMAO to gadolinium in trisbistrimethylsilylamide gadolinium. As an amount, 400 μmol of diethyl aluminum chloride (component (E-1)) was further added to obtain a polymerization catalyst composition.
Thereafter, the polymerization catalyst composition was taken out of the glove box, and an amount of the polymerization catalyst composition containing 14 μmol of gadolinium was added to a 2 L reactor containing 1,3-butadiene. This reaction system was maintained at 50 ° C. for 90 minutes, after which 8.4 g (0.1 mol) of methyl acrylate (a polar monomer) was charged and maintained at 50 ° C. for 90 minutes to perform a copolymerization reaction. Thereafter, 1 mL of an isopropanol solution (5% by mass) of 2,2′-methylene-bis (6-t-butyl-4-ethylphenol) (manufactured by Ouchi Shinko Chemical Co., Ltd., product name: Nocrack NS-5) was added, The copolymerization reaction was stopped by adding to the reaction system. Further, the reaction product was precipitated and separated by adding a large amount of isopropanol to the reactor, and further dried in vacuum at 60 ° C. to obtain a copolymer N (yield: 60 g).

(Examples 12 to 14)
Preparation of a polymerization catalyst composition and copolymerization reaction in the same manner as in Example 11 except that the amount of diethyl aluminum chloride added was changed to 50 μmol (Example 12), 100 μmol (Example 13), and 200 μmol (Example 14). To obtain copolymers O to Q (yield: 45 g in Example 12, 55 g in Example 13, and 60 g in Example 14).

(Example 15)
A polymerization catalyst composition was prepared and a copolymerization reaction was carried out in the same manner as in Example 11 except that diethyl aluminum chloride was not added, to obtain a copolymer S (yield: 50 g).

(Example 16)
260 g of a hexane solution containing 60 g (1.11 mol) of 1,3-butadiene (conjugated diene monomer) was added to a sufficiently dried stainless steel 2 L reactor.
On the other hand, in a glove box under a nitrogen atmosphere, 200 μmol of trisbistrimethylsilylamide gadolinium (Gd [N (SiMe ₃ ) ₂ ] ₃ ) ((A) component) and 2-phenylindene ((B) component) were placed in a glass container. ) 400 μmol, a total of 20.0 mmol of diisobutylaluminum hydride (10.0 mmol) / triisobutylaluminum (10.0 mmol) (component (C)) were added, and these were dissolved in 80 mL of hexane. Then, in this glass container, MMAO (manufactured by Tosoh Finechem Co., Ltd., product name: MMAO-3A) (component (D)) was added to the ratio of the moles of aluminum in MMAO to gadolinium in trisbistrimethylsilylamide gadolinium. It was added as a 600-fold amount to obtain a polymerization catalyst composition.
Thereafter, the polymerization catalyst composition was taken out of the glove box, and an amount of the polymerization catalyst composition containing 14 μmol of gadolinium was added to a 2 L reactor containing 1,3-butadiene. This reaction system was maintained at 50 ° C. for 90 minutes, after which 8.4 g (0.1 mol) of methyl acrylate (a polar monomer) was charged and maintained at 50 ° C. for 90 minutes to perform a copolymerization reaction. Thereafter, 5 mL of an isopropanol solution (5% by mass) of 2,2′-methylene-bis (6-t-butyl-4-ethylphenol) (manufactured by Ouchi Shinko Chemical Co., Ltd., product name: Nocrack NS-5) was added to The copolymerization reaction was stopped by adding to the reaction system. Further, the reaction product was precipitated and separated by adding a large amount of methanol to the reactor, and further dried in vacuum at 60 ° C. to obtain a copolymer F (yield: 60 g).
No aromatic hydrocarbons (such as toluene) were used throughout the above production.

(Example 17)
A polymerization catalyst composition was prepared and the polymerization reaction was carried out in the same manner as in Example 16 except that the amounts of trisbistrimethylsilylamide gadolinium and 2-phenylindene were reduced to half, to obtain a copolymer U (yield: 30 g).

  Table 1 shows details of the preparation of the polymerization catalyst composition and the production of the conjugated diene polymer in each of Examples and Comparative Examples.

The catalytic activity of the polymerization catalyst composition in each production is calculated by the following formula (yield (kg)) / [(amount of (A) component used (mol)) × (reaction time (hour))
Calculated from

(Analysis of copolymer)
The following (1) and (2) were analyzed for each of the copolymers obtained above.
(1) Analysis of microstructure (cis-1,4-bond content, vinyl bond amount) For each of the obtained polymers, an NMR spectrum was obtained using NMR (AVANCE 600, manufactured by Bruker). Peaks obtained by ¹ H-NMR and ¹³ C-NMR measurements ( ¹ H-NMR: δ 4.6-4.8 (= CH _{2 of} 3,4-vinyl unit)), 5.0-5.2 (-CH = of 1,4-unit), ¹³ C-NMR: δ 23.4 (1,4-cis unit), 15.9 (1,4-trans unit), 18.6 (3,4-unit) Unit)), the cis-1,4 bond amount (%) was calculated.
In addition, it was confirmed from the peaks obtained by ¹ H-NMR and ¹³ C-NMR that the copolymer was a copolymer.
Further, differential scanning calorimetry (DSC) was performed in accordance with JIS K 7121-1987 to confirm the formation of the block copolymer.
(2) Analysis of number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) Gel permeation chromatography (GPC) (GPC device: HLC-8220GPC manufactured by Tosoh Corporation; column: TSKgel GMH _XL- 2 manufactured by Tosoh Corporation) This; detector: Differential refractometer (RI)) was used to calculate the polystyrene-equivalent number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) of each copolymer based on monodisperse polystyrene. The measurement temperature was 40 ° C., and the elution solvent was THF.

  Table 1 shows the details of the analysis results of the copolymers in each of the examples and comparative examples.

* 1: Trisbistrimethylsilylamide gadolinium * 2: Bis (2-phenylindenyl) gadolinium bis (dimethylsilylamide)
* 1: Trisbistrimethylsilylamide gadolinium * 2: Bis (2-phenylindenyl) gadolinium bis (dimethylsilylamide)

  From a comparison between Examples 1 to 17 and Comparative Examples 1 to 3, the polymerization catalyst composition of the present invention containing the rare earth element compound (A) represented by the formula (C1) and the compound (B) was used. It was shown that by copolymerizing a conjugated diene monomer and a polar monomer, high catalytic activity was obtained and the desired effect of the present invention was obtained.

According to the method for producing a copolymer of the present invention, it is possible to easily produce a copolymer having a conjugated diene-derived portion having a high cis-1,4-bond content. Furthermore, according to the copolymer of the present invention, it is possible to provide a copolymer having a conjugated diene-derived moiety having a high cis-1,4-bond content. Further, according to the rubber composition of the present invention, the effects of the copolymer of the present invention can be obtained. Further, according to the rubber product of the present invention, the effects of the copolymer of the present invention can be obtained.
The rubber composition containing the copolymer of the present invention includes a tire member such as a tread, a base tread, a sidewall, a side reinforcing rubber, a bead filler; other automobile parts; a vibration-isolating rubber, a seismic isolation rubber, a belt (conveyor belt), It can be suitably used for industrial goods such as rubber crawlers and various hoses; sports goods; footwear; toys; thread rubber;

Claims (10)

The following formula (C1):
M− (AQ ¹ ) (AQ ² ) (AQ ³ ) (C1)
(Wherein, M is gadolinium, and AQ ¹ , AQ ² and AQ ³ are all a bistrialkylsilylamide group, a group represented by RO—, or a group represented by RS—, However, R is a rare earth element compound (A) represented by an alkyl group having 1 to 10 carbon atoms );
In the presence of a polymerization catalyst composition comprising a substituted or unsubstituted compound (B) having at least one selected from the group consisting of a cyclopentadienyl group, an indenyl group and a fluorenyl group,
A method for producing a copolymer, comprising a polymerization reaction step of copolymerizing a conjugated diene monomer and a polar monomer. The polymerization catalyst composition,
The following formula (C2):
YR ¹ _a R ² _b R ³ _c (C2)
(Wherein, Y is a metal element selected from the group consisting of elements of Groups 2, 12, and 13 of the periodic table , and R ¹ and R ² are hydrocarbons having 1 to 10 carbon atoms. R ³ is a hydrocarbon group having 1 to 10 carbon atoms, provided that R ¹ , R ² and R ³ may be the same or different from each other , and Y is a group 2 Or a and b are 1 and c are 0 when it is a Group 12 metal element, and a, b and c are 1 when Y is a Group 13 metal element )
The method for producing a copolymer according to claim 1, further comprising an organometallic compound represented by the following formula: In the formula (C2), R ^1, R ² and R ³ are at least one is different, the production method of the copolymer of claim 2.   The method for producing a copolymer according to any one of claims 1 to 3, wherein the compound (B) has an indenyl group.   The method for producing a copolymer according to any one of claims 1 to 4, wherein the polymerization catalyst composition further includes an aluminoxane compound.   The method for producing a copolymer according to any one of claims 1 to 5, wherein the polar monomer is a (meth) acrylic monomer or an acrylonitrile-based monomer.   The method for producing a copolymer according to any one of claims 1 to 6, wherein the conjugated diene monomer is butadiene or isoprene.   A copolymer produced by the method for producing a copolymer according to claim 1.   A rubber composition comprising the copolymer according to claim 8. A rubber product produced using the rubber composition according to claim 9.