JP2001278908A - Conjugated diene polymerization catalyst, production method of conjugated diene based polymer, and butadiene based polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a butadiene based polymer having a specific range of 1,2-bond unit content, high 1,4-cis bond unit content, and a narrow molecular- weight distribution, and to provide a catalyst for a conjugated diene polymer capable of producing the butadiene based polymer and a method for producing the polymer. SOLUTION: The butadiene polymer with 20-50 wt.% of 1,2-bond unit content in a butadiene unit, a ratio (t-BD/c-BD) of less than 0. 1 of 1,4-trans bond unit content (t-BD) to 1,4-cis bond unit content (c-BD) in a butadiene unit, a ratio (Mw/Mn) of less than 2 of weight average relative molecular (Mw) to number average relative molecular (Mn) is provided by polymerizing conjugated diene monomers in the presence of a conjugated diene polymerization catalyst consisting of (A) a compound of the fourth group transition metal in a periodic table which has one cyclopentadiene ring structure being coupled directly with an organic group having a halogen atom and (B) an aid catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a conjugated diene polymerization catalyst, a method for producing a conjugated diene-based polymer and a butadiene-based polymer, and more particularly, to a transition metal compound having one specific cyclopentadiene ring structure and a co-catalyst. A conjugated diene polymerization catalyst comprising: a method for producing a conjugated diene polymer characterized by polymerizing a monomer in the presence of the polymerization catalyst; Butadiene polymer having a 4-cis bond unit content and a narrow molecular weight distribution.

[0002]

2. Description of the Related Art Metallocene catalysts generally have high activity because of their high activity, and are also characterized by excellent control of the stereoregularity of the polymer. Are being considered. Also in the production of conjugated diene-based polymers, polymerization catalysts comprising a combination of a half metallocene compound of Group 4 of the Periodic Table with excellent control of the stereoregularity of the polymer and aluminoxane have been proposed.

[0003] Makromol. Chem. Rap. C
om. 1990, Vol. 11, p. 519 discloses a half metallocene compound of Group 4 of the periodic table having no substituent on the cyclopentadiene ring. Proceedings of the 47th Symposium on Polymer Science, 1998, Vol. 47, p. 1605,
A half-metallocene compound of Group 4 of the periodic table having an alkyl group and an alkylsilyl group on a cyclopentadiene ring is disclosed. JP-A-9-77818 discloses a half metallocene compound of Group 4 of the periodic table having an ether group-containing organic group on a cyclopentadiene ring. Macromol. Chem. , Macromo
l. Symp. 1997, Vol. 118, 55-60.
Page and Proceedings of the 1st Symposium on R & D of Industrial Science and Technology 1st Creative Technology for Creating Highly Functional Materials, December 10, 1997
Pp. 77 discloses a half metallocene compound of Group 4 of the periodic table having an ester group-containing organic group on a cyclopentadiene ring.

[0004] On the other hand, butadiene polymers are industrially used in large quantities as modifying rubbers in the field of modified resins such as high impact polystyrene (HIPS). Butadiene polymers used as modifying rubbers in this field have moderate 1,2-linked unit content and high 1,4-
It is believed that it is preferred to have a cis-linked unit content and a narrow molecular weight distribution. However, the butadiene polymers obtained by current production techniques do not fully satisfy the above requirements.

For example, when polymerization is carried out using a typical coordination polymerization catalyst having cobalt, nickel, titanium and neodymium as catalytic metal elements, a butadiene polymer having a high 1,4-cis bond unit content can be obtained. , Part 1
The 2-linkage unit content is low and the molecular weight distribution is broad. When polymerization is performed using an organolithium catalyst, living polymerization proceeds, and a butadiene polymer having a narrow molecular weight distribution is obtained.
Also, a butadiene polymer having an appropriate 1,2-bond unit content can be obtained by adding a polar compound such as an ether or an amine to the polymerization system. However, the content of the 1,4-cis bond unit is low, and the ratio of the 1,4-trans bond unit content to the 1,4-cis bond unit content is usually about 2 and extremely large. As described above, in the prior art, it was not possible to obtain a butadiene-based polymer having an appropriate 1,2-linkage unit content and a high 1,4-cis-linkage unit content and a narrow molecular weight distribution.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a butadiene-based polymer having a specific range of 1,2-linkage unit content and high 1,4-cis-linkage unit content and a narrow molecular weight distribution. An object of the present invention is to provide a method for producing a conjugated diene-based polymer that gives a polymer or the like with high activity, and a conjugated diene polymerization catalyst that can produce the butadiene-based polymer.

[0007]

Thus, according to the present invention, there is provided a transition metal compound (A) having a cyclopentadiene ring structure, wherein an organic group having a halogen atom is directly bonded to the cyclopentadiene ring. With an organoaluminum oxy compound (B1), an ionic compound (B2) capable of forming a cationic transition metal compound by reacting with the transition metal compound (A), and a cationic transition compound reacting with the transition metal compound (A). Lewis acid capable of forming metal compounds (B3)
And a conjugated diene polymerization catalyst comprising at least one cocatalyst (B) selected from organometallic compounds (B4) comprising a metal element of Groups 1, 2, 12, or 13 of the periodic table.

According to the present invention, a transition metal compound (A) belonging to Group 4 of the periodic table, which has one cyclopentadiene ring structure and an organic group having a halogen atom is directly bonded to the cyclopentadiene ring, An aluminum oxy compound (B1), an ionic compound (B) capable of reacting with the transition metal compound (A) to form a cationic transition metal compound;
2) a Lewis acid (B3) capable of reacting with the transition metal compound (A) to form a cationic transition metal compound and an organometallic compound (B4) comprising a metal element of Groups 1, 2, 12, or 13 of the periodic table A conjugated diene monomer or a conjugated diene monomer and a monomer copolymerizable therewith in the presence of a polymerization catalyst comprising at least one cocatalyst (B) selected from the group consisting of: A method for producing a conjugated diene polymer is provided.

Further, according to the present invention, the content of 1,2-linkage units in butadiene units is 20 to 50% by weight, and the content of 1,4-trans linkage units in butadiene units (tB
D) The ratio (t-BD / c-BD) between the 1,4-cis bond unit content (c-BD) and the ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) is 0.1 or less. (Mw / Mn)
Is 2 or less, and the number average molecular weight (Mn) is 10,000 to 1,0.
A butadiene-based polymer having a molecular weight of 00000 is provided.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION (Conjugated Diene Polymerization Catalyst) The conjugated diene polymerization catalyst of the present invention has one cyclopentadiene ring structure, and an organic group having a halogen atom is directly bonded to the cyclopentadiene ring. A group 4 transition metal compound (A), an organic aluminum oxy compound (B1),
An ionic compound (B2) capable of producing a cationic transition metal compound by reacting with the transition metal compound (A), and a Lewis acid (B3) capable of producing a cationic transition metal compound by reacting with the transition metal compound (A) And Periodic Tables 1, 2,
Organometallic compounds consisting of Group 12 or 13 metal elements (B
And at least one cocatalyst (B) selected from 4).

Transition metal compound (A) used in the present invention has a single cyclopentadiene ring structure, and an organic group having a halogen atom is directly bonded to the cyclopentadiene ring. Is preferably a compound represented by the following general formula 1. General formula 1:

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Wherein L is an organic group having a cyclopentadiene ring structure, M is a transition metal of Group 4 of the periodic table, Q is an organic group on the cyclopentadiene ring, and at least one of Q is a halogen atom. M is an integer of 1 to 5. E is a hydrogen atom, halogen, a hydrocarbon group having 1 to 12 carbon atoms, a hydrocarbon oxy group having 1 to 12 carbon atoms, or
An amino group substituted with a hydrocarbon group having 1 to 12 carbon atoms. A plurality of E may be the same or different from each other;
May be combined with a cyclopentadiene ring to form a cyclic structure. n is 2 or 3. )

That is, the transition metal compound (A) represented by the general formula 1 has only one condensed ring organic group having a cyclopentadiene ring structure such as cyclopentadiene, indene, and fluorene as a ligand.
A half metallocene compound having at least one organic group having a halogen atom on the cyclopentadiene ring of the ligand. The transition metal of Group 4 of the periodic table (M in the formula) is preferably titanium, zirconium or hafnium, and more preferably titanium.

Q is an organic group on the cyclopentadiene ring, and at least one of Q is an organic group having a halogen atom. m is an integer of 1 to 5. When m is 2 or more, Q may be the same or different from each other. The preferred integer m is 1. Examples of the halogen in Q include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, a fluorine atom, a chlorine atom and a bromine atom are preferred, a fluorine atom and a chlorine atom are more preferred, and a fluorine atom is particularly preferred. Examples of the organic group Q having a halogen atom include carbon atoms of 1
And halogenated alkyl groups having 6 to 20 carbon atoms, aralkyl halide groups having 7 to 20 carbon atoms, and the like.

Examples of the halogenated alkyl group include fluoromethyl, 2-fluoroethyl, 2-chlorosiethyl,
-Bromoethyl, 2-iodoethyl, 2,2-difluoroethyl, 2,2,2-trifluoroethyl, 2-fluoropropyl, 3-fluoropropyl and the like. Examples of the halogenated aryl group include 2-fluorophenyl, 3-fluorophenyl, 4-fluorophenyl,
2,6-difluorophenyl and the like. Examples of the halogenated aralkyl group include 2-fluorobenzyl, 3
-Fluorobenzyl, 4-fluorobenzyl, 2,6-
Difluorobenzyl, 2,4,6-trifluorobenzyl, 2- (2-fluorophenyl) ethyl and the like. Among these, a halogenated aralkyl group is preferable, and among them, a fluoroaralkyl group such as 2-fluorobenzyl is more preferable.

Other organic groups Q include those having 1 to 2 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl, hexyl, octyl and cyclohexyl.
0 alkyl groups, aralkyl groups having 7 to 20 carbon atoms such as benzyl and triphenylmethyl. Other organic groups Q include a trimethylsilyl group,
Such as trimethylstannyl group and trimethylgermyl group,
In addition to organic metal groups consisting of hydrocarbon groups having 1 to 6 carbon atoms and silicon, tin or germanium, thioether groups, carbonyl groups, sulfonyl groups, ester groups, thioester groups, amino groups, alkyl-substituted amino groups, amide groups, etc. And the like.

Among the compounds represented by E, examples of the halogen include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a chlorine atom is preferred. Among those represented by E, examples of the hydrocarbon group include an alkyl group having 1 to 12 carbon atoms such as methyl, ethyl, isopropyl, butyl and neopentyl, and an aralkyl group having 7 to 12 carbon atoms such as benzyl. Among those represented by E, examples of the hydrocarbonoxy group include an alkoxy group having 1 to 12 carbon atoms such as methoxy, ethoxy and isopropoxy, and an aralkyloxy group having 7 to 12 carbon atoms such as benzyloxy.

Of those represented by E, those having 1 to 1 carbon atoms
Examples of the amino group substituted with 12 hydrocarbon groups include dimethylamino, diethylamino, diisopropylamino,
1 carbon atoms such as dibutylamino and di-t-butylamino
And a dialkylamino group having from 12 to 12 alkyl groups. These carbon atoms constituting E may be substituted by silicon atoms. E may be bonded to a cyclopentadiene ring to form a cyclic structure. In this case, the transition metal compound (A) becomes a so-called geometrically constrained catalyst having a metallocycle structure. When E is bonded to the cyclopentadiene ring, an oxygen atom, a sulfur atom,
It may be via a nitrogen atom or the like. n is an integer of 2 or 3, and is preferably 3.

The specific compound of the transition metal compound (A) is not particularly limited, but for example, the following (1) to (1)
And (5). (1) Substituted cyclopentadienyl titanium tri (or di) halide Specific examples include 2-fluorobenzylcyclopentadienyl titanium tri (or di) chloride and 2-chlorobenzylcyclopentadienyl titanium tri (or di). Bromide, 2-bromobenzylcyclopentadienyl titanium tri (or di) chloride, 2-iodobenzylcyclopentadienyl titanium tri (or di) chloride, 2-fluorophenylcyclopentadienyl titanium tri (or di) chloride, (1-t
-Butyl) (2-fluorobenzyl) cyclopentadienyltitanium tri (or di) chloride, (1,2-
Dimethyl) [3- (2-fluorobenzyl)] cyclopentadienyltitanium tri (or di) chloride,
(1,2,4-trimethyl) [3- (2-fluorobenzyl)] cyclopentadienyltitanium tri (or di) chloride, (tetramethyl) (2-fluorobenzyl) cyclopentadienyltitanium tri (or di) )
Chloride and the like. Among them, (2-fluorobenzyl) cyclopentadienyltitanium trichloride is preferred.

(2) Indenyl titanium tri (or di) halide having a substituent on the cyclopentadiene ring Specific examples include [1- (2-fluorobenzyl)] indenyl titanium tri (or di) chloride, [ 1-
(2-fluorobenzyl)] (3-methyl) indenyltitanium tri (or di) chloride, [1- (2-2)
-Fluorobenzyl)] (2,3-dimethyl) indenyltitanium tri (or di) chloride.

(3) Fluorenyl titanium tri (or di) halide having a substituent on the cyclopentadiene ring Specific examples include [9- (2-fluorobenzyl)] fluorenyl titanium tri (or di) chloride And the like. (4) A compound in which all or a part of the halogen atoms bonded to the central metal of the compounds of (1) to (3) are substituted with a hydrocarbon group or a hydrocarbonoxy group. Specific examples include (2-fluorobenzyl) Cyclopentadienyltitanium tri (or di) benzyl, (2
-Fluorobenzyl) cyclopentadienyltitanium tri (or di) butoxide and the like.

(5) Compound in which titanium, which is the central metal of the compounds of (1) to (4), is replaced with zirconium or hafnium. Specific examples include (2-fluorobenzyl) cyclopentadienyl zirconium tri (or di). Chloride,
(2-fluorobenzyl) cyclopentadienyl hafnium tri (or di) chloride, [1- (2-fluorobenzyl)] indenyl zirconium tri (or di)
Chloride and the like. As the transition metal compound (A), among the compounds (1) to (5), (1)
Compounds having the structure are preferred.

Organic aluminum oxy compound (B1) The organic aluminum oxy compound (B1) used in the present invention
1) is a compound having a structure represented by the following general formula 2 or 3. General formula 2:

[0024]

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General formula 3:

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(Where R ^{1 to} R ⁶ are a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms or a hydrocarbon oxy group having 1 to 10 carbon atoms, respectively. S is 0 or more. It is an integer, preferably 5 or more, and the upper limit is preferably 1
00, more preferably 50. R ^{1 to} R ⁶ are
Each may be the same or different. )

Examples of the halogen atom in the general formulas 2 and 3 include a fluorine atom, a bromine atom, a chlorine atom and an iodine atom. Among them, a chlorine atom is preferable. General formula 2
Examples of the hydrocarbon group in and 3 include a methyl group, an ethyl group, a propyl group, a butyl group, an octyl group, and a phenyl group. Among them, a methyl group, an ethyl group, a propyl group, and a butyl group are preferable. Examples of the hydrocarbon oxy group in the general formulas 2 and 3 include a methoxy group, an ethoxy group, and a butoxy group.

Specific examples of the organic aluminum oxy compound (B1) include methylaluminoxane, ethylaluminoxane, propylaluminoxane, butylaluminoxane, chloroaluminoxane and the like. Among them, methylaluminoxane is preferred. The organic aluminum oxy compound (B1) can be synthesized by reacting an organic aluminum metal compound with water.

Examples of the organic aluminum metal compound include trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, diethylaluminum hydride, dimethylaluminum chloride, diethylaluminum chloride, methylaluminum sesquichloride, ethylaluminum sesquichloride, and methylaluminum Dichloride, ethylaluminum dichloride and the like.
Also, a mixture of these can be used.

Ionic Compound (B2) The ionic compound (B2) used in the present invention is a compound capable of reacting with the transition metal compound (A) to form a cationic transition metal compound. It is an ionic compound composed of a cation.

The non-coordinating anion is not particularly limited, and examples thereof include an organic boron compound anion. Examples of the organic boron compound anion include tetra (phenyl) borate, tetra (fluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluorophenyl) borate, and tetrakis (pentafluorophenyl) borate , Tetrakis (tetrafluoromethylphenyl) borate, tetra (triyl) borate, tetra (xylyl) borate, (triphenylpentafluorophenyl) borate, [tris (pentafluorophenyl) phenyl] borate and the like.

The cation is not particularly limited.
For example, a carbonium ion, an oxonium ion, an ammonium ion, a phosphonium ion, and a ferrocenium ion can be given. As carbonium ions,
Triphenylcarbonium ion, tri (methylphenyl) carbonium ion, tri (dimethylphenyl) carbonium ion and the like. Examples of the oxonium ion include a methyloxonium ion, a dimethyloxonium ion, and a trimethyloxonium ion.

As the ammonium ion, trimethylammonium ion, triethylammonium ion,
Trialkyl ammonium ions such as tripropyl ammonium ion and tributyl ammonium ion;
Dialkylammonium ions such as diisopropylammonium ion and dicyclohexylammonium ion; N, N-diethylanilinium ion and N, N-
N, N-dialkylanilinium ions such as dimethyl-2,4,6-trimethylanilinium ion; and the like. Examples of the phosphonium ion include a triphenylphosphonium ion, a tri (methylphenyl) phosphonium ion, and a tri (dimethylphenyl) phosphonium ion. Examples of the ferrocenium ion include a 1,1′-dimethylferrocenium ion.

The ionic compound (B2) is an ionic compound which is arbitrarily selected from the above-mentioned non-coordinating anions and cations. Above all, specific examples of preferred ionic compound (B2) include tri (methylphenyl) carbonium tetrakis (pentafluorophenyl) borate, triphenylcarbonium tetrakis (pentafluorophenyl) borate, N, N-
Dimethylanilinium tetrakis (pentafluorophenyl) borate and 1,1′-dimethylferrocenium tetrakis (pentafluorophenyl) borate are exemplified.

Lewis acid (B3) The Lewis acid (B3) used in the present invention can react with the transition metal compound (A) to form a cationic transition metal compound, and is not particularly limited. Number 1
And an organic boron compound having 10 to 10 hydrocarbon groups bonded thereto. The hydrogen atom of the hydrocarbon group may be substituted with a halogen atom or the like. Specific examples of the organic boron compound include trimethylboron, triphenylboron, tris (pentafluorophenyl) boron, tris (monofluorophenyl) boron, and tris (difluorophenyl) boron.

Organometallic Compound (B4) The organometallic compound (B4) used in the present invention, which is composed of a metal element of Groups 1, 2, 12, or 13 of the periodic table, is not particularly limited. Examples include magnesium compounds, organoaluminum compounds, organoaluminum hydrides, organomagnesium halides, and organoaluminum halides.

Examples of the organic lithium compound include methyl lithium, butyl lithium, phenyl lithium and the like. Examples of the organomagnesium compound include dibutylmagnesium. Examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, triisopropylaluminum, and triisobutylaluminum. Examples of the organic aluminum hydride include diethyl aluminum hydride and ethyl aluminum sesquihydride.

As the organic magnesium halide,
Ethyl magnesium chloride, butyl magnesium chloride and the like can be mentioned. Examples of the organoaluminum halide include dimethylaluminum chloride, diethylaluminum chloride, methylaluminum sesquichloride, ethylaluminum sesquichloride, methylaluminum dichloride, and ethylaluminum dichloride.

(Method for Producing Conjugated Diene-Based Polymer) The conjugated diene-based polymer of the present invention has one cyclopentadiene ring structure and a periodic table in which an organic group having a halogen atom is directly bonded to the cyclopentadiene ring. Group 4 transition metal compound (A), an organoaluminum oxy compound (B1), and an ionic compound (B) that can react with the transition metal compound (A) to form a cationic transition metal compound
2) a Lewis acid (B3) capable of reacting with the transition metal compound (A) to form a cationic transition metal compound and an organometallic compound (B4) comprising a metal element of Groups 1, 2, 12, or 13 of the periodic table A conjugated diene monomer or a conjugated diene monomer and a monomer copolymerizable therewith in the presence of a polymerization catalyst comprising at least one cocatalyst (B) selected from Can be

The conjugated diene monomer used in the present invention includes 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2
-Chloro-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene and the like. Among the conjugated diene monomers, 1,3-butadiene and 2-methyl-
1,3-butadiene is preferred, and 1,3-butadiene is more preferred. These conjugated diene monomers can be used alone or in combination of two or more, but it is particularly preferable to use 1,3-butadiene alone.

The monomers copolymerizable with the conjugated diene monomer include styrene, o-methylstyrene, p-methylstyrene, m-methylstyrene, 2,4-dimethylstyrene, ethylstyrene and p-methylstyrene. tert-butylstyrene, α-methylstyrene, α-methyl-p-methylstyrene, o-chlorostyrene, m-chlorostyrene, p
-Chlorostyrene, p-bromostyrene, 2-methyl-
1,4-dichlorostyrene, 2,4-dibromostyrene, aromatic vinyl such as vinylnaphthalene, ethylene,
Olefins such as propylene and 1-butene; cyclic olefins such as cyclopentene and 2-norbornene;
-Hexadiene, 1,6-heptadiene, 1,7-octadiene, dicyclopentadiene, 5-ethylidene-2
Non-conjugated dienes such as -norbornene; (meth) acrylates such as methyl methacrylate;

The amounts of the cocatalysts in the polymerization catalyst used in the present invention are respectively prepared as follows. Organoaluminum oxy compound (B1) / transition metal compound (A)
(The (B1) is calculated in terms of aluminum atom equivalent) is usually 10 to 10,000, preferably 50.
5,000, more preferably 100-3,000. The molar ratio of the ionic compound (B2) / the transition metal compound (A) is usually 0.01 to 100, preferably 0.1 to 100.
It is 10. Lewis acid (B3) / transition metal compound (A)
Is usually 0.01 to 100, preferably 0.1 to 100.
10 to 10. The molar ratio of the organometallic compound (B4) / transition metal compound (A) is usually 0.1 to 10,000, preferably 1 to 1,000. Regardless of whether the amount of the cocatalyst used is small or large, the polymerization activity decreases. The respective cocatalysts can be used as a mixture.

The amount of the polymerization catalyst used in the present invention is usually 0.01 to 50 mmol, preferably 0.05 to 50 mol, per mol of the transition metal compound (A) per 1 mol of the monomer.
It is 10 mmol, more preferably 0.1 to 5 mmol. If the amount of the catalyst used is small, the polymerization activity decreases,
If the amount is large, the molecular weight of the obtained polymer decreases.

In the method for producing a conjugated diene polymer of the present invention, the transition metal compound (A) and the cocatalyst (B) may be separately contacted with a conjugated diene monomer, respectively. It is preferable to contact with the conjugated diene monomer after having been previously contacted under the condition satisfying the formula β. Formula α: 0 ≦ T ≦ 50 Formula β: 0.5 ≦ t ≦ 2000exp (−0.0921
T)

That is, the contact temperature (T, ° C) between the transition metal compound (A) and the co-catalyst (B) is preferably from 0 to 50.
° C, more preferably 10 to 40 ° C, still more preferably 1 to 40 ° C.
5-35 ° C. When the contact temperature is low, Mw / Mn of the obtained polymer increases, and when it is high, the polymerization activity decreases.

The contact time (t, min) between the transition metal compound (A) and the cocatalyst (B) is preferably a time satisfying 0.5 ≦ t ≦ 2000 exp (−0.0921T), and 1 ≦ t A time that satisfies ≦ 1000exp (−0.0921T) is more preferable, and a time that satisfies 2 ≦ t ≦ 500exp (−0.0921T) is more preferable. When the contact time is short, the Mw / Mn of the obtained polymer increases, and when the contact time is long, the polymerization activity decreases.

Transition metal compound (A) and cocatalyst (B)
Can be used in the form of either a solution or a slurry, but in order to obtain higher polymerization activity, a solution is preferable. The solvent used for preparing the solution or slurry is a hydrocarbon solvent such as butane, pentane, hexane, heptane, octane, cyclohexane, mineral oil, benzene, toluene, xylene, or chloroform, methylene chloride, dichloroethane, chlorobenzene, -Chlorotoluene, 4
-Chlorotoluene, 2,6-dichlorotoluene, 1,
2,4-trichlorobenzene, 2-fluorotoluene,
Halogenated hydrocarbon solvents such as 4-fluorotoluene. These solvents may be used as a mixture of two or more kinds. Of these, aromatic hydrocarbons and halogenated aromatic hydrocarbons are preferred.

The polymerization catalyst used in the method for producing a conjugated diene polymer of the present invention is used by supporting the components of the polymerization catalyst on a carrier in order to prevent contamination of the polymerization catalyst due to adhesion to the polymerization reactor. You may. Examples of the carrier include carbon black, an inorganic compound, and an organic polymer compound. As inorganic compounds, inorganic oxides, inorganic chlorides,
Examples thereof include inorganic hydroxides and the like, and may contain a small amount of carbonate or sulfate. Preferred specific examples include inorganic oxides such as silica, alumina, magnesia, titania, zirconia, and calcia, and inorganic chlorides such as magnesium chloride. These inorganic compounds have an average particle diameter of 5 to 150 μm and a specific surface area of ² to 800 m ² / g.
It is preferably a porous particle of 100 to 8
Heat treatment is performed at 00 ° C. to remove water and used as a carrier.

The organic polymer compound preferably has an aromatic ring, a substituted aromatic ring, or a functional group such as a hydroxy group, a carboxyl group, an ester group, or a halogen atom in the side chain. These are acrylic acid, methacrylic acid,
It can be obtained by polymerizing a monomer composed of vinyl chloride, vinyl acetate, styrene, divinylbenzene or the like, or chemically modifying a polymer having an α-olefin monomer unit such as ethylene, propylene or butene. Specific examples include a carboxy-modified crosslinked styrene copolymer composed of styrene-methacrylic acid-divinylbenzene. These organic polymer compounds have an average particle diameter of 5-2.
It is preferable to use the carrier in the form of 50 μm spherical particles.

The polymerization method employed in the method for producing a conjugated diene polymer of the present invention is not particularly limited, but includes a bulk polymerization method, a solution polymerization method and a slurry polymerization method in an inert solvent, and a gas phase stirring method. Gas phase polymerization using a tank and a gas phase fluidized bed. Among these methods, the solution polymerization method is preferable because the molecular weight distribution can be narrowed. Further, both a batch polymerization method and a continuous polymerization method can be employed.

The inert solvent used in the solution polymerization method is not particularly limited, but is a hydrocarbon solvent such as butane, pentane, hexane, heptane, octane, cyclohexane, mineral oil, benzene, toluene, xylene, or chloroform, methylene chloride. And halogenated hydrocarbon solvents such as dichloroethane, chlorobenzene, 2-chlorotoluene, 4-chlorotoluene, 2,6-dichlorotoluene, 1,2,4-trichlorobenzene, 2-fluorotoluene and 4-fluorotoluene. These solvents may be used as a mixture of two or more kinds. Of these, aromatic hydrocarbon solvents and halogenated aromatic hydrocarbon solvents are preferred.

The polymerization temperature in the method for producing a conjugated diene polymer of the present invention is not particularly limited, but is preferably -10.
0 ° C to + 100 ° C, more preferably -80 ° C to 50 ° C
° C, more preferably -60 ° C to 30 ° C, particularly preferably -40 ° C to 0 ° C. If this polymerization temperature is high,
Mw / Mn of the obtained polymer increases. Also, -1
A polymerization reaction at an extremely low temperature of not more than 00 ° C. is not preferable in view of production cost. The polymerization time is about 1 minute to 50 hours, and the polymerization pressure is about 1 to 30 kg / cm ² .

In the method for producing a conjugated diene polymer of the present invention, a chain transfer agent can be added to adjust the molecular weight of the polymer. As the chain transfer agent, 1,4
-Those conventionally used in the production of cis-polybutadiene rubber can be used in the same manner.
Examples include allenes such as 2-butadiene, cyclic dienes such as cyclooctadiene, and hydrogen.

In the method for producing a conjugated diene polymer of the present invention, since the polymerization reaction proceeds in a living manner, a reagent capable of reacting with a living polymer having a catalytic metal at a molecular terminal before termination of the polymerization reaction. Can be added to the polymerization system to react with the living polymer. Usually, a monofunctional reagent is called a terminal modifier, and a polyfunctional reagent is called a coupling agent. In the case of a terminal modifier, it forms a structure bonded to the end of a living polymer, and in the case of a coupling agent, a structure formed by bonding two or more living polymers. They can be used in combination.

The terminal modifier is not particularly restricted but includes, for example, epoxy compounds such as ethylene oxide and styrene oxide; isocyanate compounds such as phenyl isocyanate and butyl isocyanate;
4'-bis (diethylamino) benzophenone, 4,
N-substituted aminoketones such as 4'-bis (diphenylamino) benzophenone; N-substituted benzaldehydes such as 4-dimethylaminobenzaldehyde and 4-diphenylaminobenzaldehyde; N, N-diethylacetamide, N, N-dimethylaminoacetamide Carboxylic acid amides such as N-methyl-2-pyrrolidone, N
N-substituted pyrrolidones such as -phenyl-2-pyrrolidone; and the like. In the case of a terminal modifying agent, it may cause a structural change upon binding to the terminal of the living polymer and further react with another terminal of the living polymer to act as if it were a coupling agent.

The coupling agent is not particularly restricted but includes, for example, silicon halide compounds containing at least two halogen atoms such as silicon tetrachloride, silicon tetrabromide, trichloromethylsilane, hexachlorodisilane; tetramethoxysilane; Organosilicon compounds containing two or more alkoxy groups having 1 to 8 carbon atoms, such as tetraethoxysilane, methyltrimethoxysilane, and phenyltrimethoxysilane; at least two organosilicon compounds such as tin tetrachloride, tin tetrabromide, and dimethyltin dichloride; And a halogenated tin compound containing a halogen atom.

When a living polymer is reacted with a terminal modifier or a coupling agent, a Mooney viscosity stabilizer is appropriately added to the obtained polymer in order to suppress a change in Mooney viscosity during storage of the polymer. It may be added in an amount. The Mooney viscosity stabilizer is not particularly limited. For example, monoamine compounds such as butylamine, hexylamine, diphenylamine, triethylamine, aniline, and benzylamine; m-phenylenediamine, N,
Polyvalent amine compounds such as N′-dimethyl-p-phenylenediamine; and the like. These compounds are 2
A mixture of more than one species may be used.

To the butadiene polymer of the present invention, an appropriate amount of an antioxidant may be added in order to prevent deterioration during removal and storage of the polymer. Antioxidants include, for example, 2,6-di-t-butyl-4-methylphenol,
Phenolic antioxidants such as 2,6-di-t-butyl-4-isobutylphenol; sulfur antioxidants such as dilaurylthiodipropionate and distearylthiodipropionate; tris (nonylphenyl) phosphite , A phosphorus-based antioxidant such as tris (2,4-di-t-butylphenyl) phosphite; phenyl-α-
Amine-based antioxidants such as naphthylamine and p-isopropoxydiphenylamine; and the like. These antioxidants may be used as a mixture of two or more.

The termination of the polymerization reaction is usually carried out at a predetermined point in time.
It is carried out by adding a polymerization terminator to the polymerization system.
Examples of the polymerization terminator include water; alcohols such as methanol, ethanol, propanol, butanol and isobutanol; inorganic acids such as hydrochloric acid; and organic acids such as citric acid, versatic acid and dodecylbenzenesulfonic acid. These polymerization terminators may be used as a mixture of two or more. The method of recovering the polymer after the termination of the polymerization reaction may be a conventional method, such as a steam stripping method or a method of precipitating the polymer in a poor solvent.

(Butadiene-based polymer) The butadiene-based polymer of the present invention has a 1,2-linkage unit content in a butadiene unit of 20 to 50% by weight and a 1,4-trans linkage unit content in a butadiene unit (t). -BD) and the ratio (t-BD / c-BD) of the 1,4-cis bond unit content (c-BD) to 0.1 or less, and the weight average molecular weight (Mw) and the number average molecular weight (Mn) A butadiene-based polymer having a ratio (Mw / Mn) of 2 or less and a number average molecular weight (Mn) of 10,000 to 1,000,000.

In the butadiene polymer of the present invention,
The 2-bond unit content is from 20 to 20 in the butadiene unit of the polymer.
It is 50% by weight, preferably 22 to 40% by weight, more preferably 24 to 30% by weight. In the butadiene-based polymer of the present invention, the 1,4-trans bond unit content (t-BD) and the 1,4-cis bond unit content (c
-BD) (t-BD / c-BD) is 0.1 or less, preferably 0.05 or less, more preferably 0.0 or less.
3 or less, more preferably 0.02 or less.

The ratio (Mw) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the butadiene polymer of the present invention is
(w / Mn) is 2.0 or less, preferably 1.6 or less, more preferably 1.4 or less, and particularly preferably 1.2 or less. The number average molecular weight of the butadiene polymer of the present invention (M
n) is from 10,000 to 1,000,000, preferably from 50,000 to 600,000, more preferably 10
It is between 0.00000 and 400,000.

The butadiene-based polymer of the present invention can be suitably used as a modifying rubber in the field of modified resins such as impact-resistant polystyrene (HIPS) and used as a raw material rubber for tires and industrial rubber parts. can do.

[0064]

EXAMPLES The present invention will be specifically described below with reference to examples. (Example 1) 2-fluorobenzylcyclopentadienyl titanium
Synthesis of trichloride (abbreviated as complex I ) 2-Fluorobenzyl chloride (9.1 g) was added to 45 mL (90 mmol) of a solution of cyclopentadienyl sodium in tetrahydrofuran (THF) (2.0 mol / L, manufactured by Aldrich). Tetrahydrofuran solution 50
ml was slowly added dropwise at -78 ° C under a nitrogen atmosphere. After completion of the dropwise addition, the mixture was stirred at room temperature for 3 hours, and about 1 ml of methanol was added to terminate the reaction. The reaction mixture was poured into 300 ml of ice water, and the organic component was extracted with n-hexane, which was washed with water and saturated saline. The obtained hexane solution was dried over magnesium sulfate, concentrated by a rotary evaporator, and the resulting residue was distilled under reduced pressure (54 ° C., 1 mm
Hg) to give 2-fluorobenzylcyclopentadiene (8.7 g, yield 50%) as a colorless liquid.

In a mixed solution of 2-fluorobenzylcyclopentadiene (3.07 g, 17.6 mmol) in tetrahydrofuran / n-hexane, 12.1 ml (19.4 ml) was added.
mmol) in n-butyllithium in hexane (1.6
mol / L) was slowly added dropwise at -78 ° C under a nitrogen atmosphere. After the dropwise addition, the mixture was stirred at room temperature for 1 hour, cooled to -78 ° C again, and chlorotrimethylsilane (2.53 ml, 20 mmol
l) An n-hexane solution (10 ml) was slowly added dropwise. After completion of the dropwise addition, the mixture was stirred at room temperature for 3 hours, and then about 1 ml
Was added to terminate the reaction. Add 3 reaction mixtures
The mixture was poured into ice water (00 ml), the organic component was extracted with n-hexane, and this was washed with water and saturated saline. The obtained hexane solution was dried over magnesium sulfate, and concentrated by a rotary evaporator, and the resulting residue was distilled under reduced pressure (7.
7-80 ° C, 1 mmHg) to give (2-fluorobenzyl) (trimethylsilyl) cyclopentadiene (3.66 g, yield 85%) as a yellow liquid.

(2-Fluorobenzyl) (trimethylsilyl) cyclopentadiene (4.32 g, 17.7 mm)
ol) in n-hexane (50 ml), titanium tetrachloride (1.94 ml) was added at -78 ° C under a nitrogen atmosphere, and stirring was continued at room temperature for 3 hours. The reaction solution was cooled to −30 ° C. to precipitate yellow crystals (2.32 g, 45%). ¹ H-NMR confirmed that the product was 2-fluorobenzylcyclopentadienyltitanium trichloride. (CDCl3, ppm) 4.19 (2H, s), 6.
84 (2H, t, j = 2.9 Hz), 6.92 (2H,
t, j = 2.9 Hz), 7.00-7.15 (2H,
m), 7.21-7.31 (2H, m)

Polymerization of 1,3-butadiene In a sealed pressure-resistant glass ampoule having an inner volume of 150 ml, 25.54 g of toluene and 1.7 of butadiene were placed under a nitrogen atmosphere.
1 g was charged. Methylaluminoxane [17.0 mm
ol (in terms of aluminum atom equivalent, the same applies hereinafter), manufactured by Tosoh Akzo Co., Ltd.) and 2-fluorobenzylcyclopentadienyltitanium trichloride (0.01
A solution obtained by aging a toluene solution of 7 mmol (hereinafter abbreviated as “complex I”) at 25 ° C. for 5 minutes was added to the ampoule, and polymerized at 25 ° C. for 15 minutes. The polymerization reaction was stopped by adding a small amount of methanol, and then the polymerization solution was poured into a large amount of acidic methanol containing an antioxidant to precipitate a polymer. The polymer was redissolved in toluene and the solution was centrifuged to remove ash and reprecipitated in acidic methanol. The purified polymer was dried and weighed to determine the polymer yield.

The molecular weight and the molecular weight distribution were determined by gel permeation chromatography (GPC) analysis based on a calibration curve prepared using a standard polybutadiene sample (manufactured by Polymer Laboratories). A column in which G-7000, G-5000 and G-4000 manufactured by Tosoh Corporation were connected was used as a column, and THF was used as an eluent. Table 1 shows the results.

The microstructure of the polymer (1,4-cis, 1,
4-trans and 1,2-linking unit content) is ¹ H-NM
It was determined by R analysis and ¹³ C-NMR analysis. Ie
^{In the 1} H-NMR spectrum, 5.4-5.6 pp
The intensity ratio of the signal derived from the unsaturated methine proton in the 1,4-linkage unit appearing at m and the signal derived from the unsaturated methylene proton in the 1,2-linkage unit appearing at 5.0-5.1 ppm is 1 , 4-linkage unit content and 1,2
-The binding unit content was calculated. In the ¹³ C-NMR spectrum, a signal derived from a saturated methylene carbon in the 1,4-cis bond unit (mainly 27.4 ppm) and 1,
From the intensity ratio of the signal (mainly 32.7 ppm) derived from the saturated methylene carbon in the 4-trans bond unit, 1,4
-The ratio of the content of cis-linked units to the content of trans-linked units in the linked units was calculated. Table 1 shows the results.

Comparative Example 1 The same as Example 1 except that cyclopentadienyltitanium trichloride (abbreviated as complex II) was used as the transition metal compound instead of complex I, and the polymerization time was changed to 20 minutes. Was subjected to polymerization of 1,3-butadiene and analysis of the polymer. Table 1 shows the results.

(Example 2) The aging of the polymerization catalyst was 25
Example 1 except that the polymerization was carried out at -25 ° C for 10 minutes, and then the polymerization reaction was carried out at -25 ° C for 3 hours.
In the same manner as in 1, polymerization of 1,3-butadiene and analysis of the polymer were performed. Table 1 shows the results.

Comparative Example 2 Polymerization of 1,3-butadiene and analysis of the polymer in the same manner as in Example 2 except that complex II was used instead of complex I as the transition metal compound and the polymerization time was changed to 5 hours. Was done. Table 1 shows the results.

[0073]

[Table 1]

When Example 1 and Comparative Example 1 are compared, the microstructure of the butadiene polymer obtained by introducing a 2-fluorobenzyl group into the cyclopentadiene ring has a low trans-bond unit content / cis-bond unit content ratio. It can be seen that the content of the 1,2-linkage unit increases while maintaining the content.
In Example 2, living polymerization of 1,3-butadiene proceeds, and a butadiene polymer having an extremely narrow molecular weight distribution is obtained. Comparing Example 2 with Comparative Example 2, the introduction of a 2-fluorobenzyl group into the cyclopentadiene ring significantly increases the polymerization activity, and furthermore, the microstructure of the butadiene polymer has a low trans-binding unit content / cis It can be seen that the 1,2-linking unit content increases while maintaining the binding unit content ratio.

[0075]

The novel conjugated diene polymerization catalyst of the present invention has a novel butadiene system having a narrow range of molecular weight distribution, having a specific range of 1,2-bond unit content and a high 1,4-cis bond unit content. A polymer is obtained efficiently.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuzou Suzuki 1-1 Institute of Industrial Science and Technology, Tsukuba City, Ibaraki Prefecture (72) Inventor Satoshi Miyazawa 1-1 Institute of Technology East, Tsukuba City, Ibaraki Prefecture Inside the Institute of Quality Engineering (72) Inventor Kenji Tsuchihara 1-1 East Higashi, Tsukuba City, Ibaraki Prefecture Inside the Institute of Materials Science and Technology (72) Inventor Hideaki Hagiwara 1-1 East Higashi Tsukuba City, Ibaraki Prefecture Inside the Engineering Research Institute (72) Inventor Masahide Murata 2-315-504, Suido 2-chome, Bunkyo-ku, Tokyo (72) Inventor Hiroyuki Ozaki 4-6-202 Onogawa, Tsukuba-shi, Ibaraki Prefecture (72) Inventor Masanao Kawabe 2-72-6-203 Takezono, Tsukuba-shi, Ibaraki Prefecture (72) Inventor Yoshifumi Fukui 4-63-507 Ninomiya 4-chome, Tsukuba-shi, Ibaraki Prefecture (72) Inventor Jiju 2-7-2 Kodano, Kanazawa City, Ishikawa Prefecture (72) Inventor Juan Bante 2-2-2 Umezono Tsukuba City, Ibaraki Prefecture (72) Inventor Toshio Kase 5-2-2 Matsushiro Tsukuba City, Ibaraki Prefecture F-term ( Reference) 4J028 AA01A AB00A AB01A AC01A AC10A AC28A BA00A BA00B BA01A BA01B BA02B BB00A BB00B BB01B BB02B BC01B BC05B BC06B BC13A BC15B BC16B EC17B BC19B BC25B BC27B CB94EB04 EB01 DB04A DB04EB04 EB04 EB04 AA02Q AA03Q AA04Q AB00Q AB02Q AB04Q AB07Q AL03Q AR04Q AR11Q AR22Q AS01P AS02P AS03P AS04P AS07P AS11Q AS15Q BA03H BA31H BA46H BB01Q BB03Q BC43H BC68H CA01 CA04 CA15 CA31 DA01 HC04 HC51 HC51 HC

Claims (3)

[Claims] 1. A transition metal belonging to Group 4 of the periodic table (A) having one cyclopentadiene ring structure and an organic group having a halogen atom directly bonded to the cyclopentadiene ring, and an organic aluminum oxy compound (B1) An ionic compound (B2) capable of reacting with the transition metal compound (A) to form a cationic transition metal compound, and a Lewis acid (B3) capable of reacting with the transition metal compound (A) to form a cationic transition metal compound. ) And Periodic Table 1, 2, 1
Organometallic compounds consisting of Group 2 or 13 metal elements (B
A conjugated diene polymerization catalyst comprising at least one cocatalyst (B) selected from 4). 2. A transition metal belonging to Group 4 of the Periodic Table (A) having one cyclopentadiene ring structure and an organic group having a halogen atom directly bonded to the cyclopentadiene ring, and an organic aluminum oxy compound (B1) An ionic compound (B2) capable of reacting with the transition metal compound (A) to form a cationic transition metal compound, and a Lewis acid (B3) capable of reacting with the transition metal compound (A) to form a cationic transition metal compound. ) And Periodic Table 1, 2, 1
Organometallic compounds consisting of Group 2 or 13 metal elements (B
Polymerizing a conjugated diene monomer or a conjugated diene monomer and a monomer copolymerizable therewith in the presence of a polymerization catalyst comprising at least one cocatalyst (B) selected from 4) A method for producing a conjugated diene-based polymer, characterized in that: 3. The content of 1,2-linkage units in butadiene units is 20 to 50% by weight, the content of 1,4-trans linkage units (t-BD) and the content of 1,4-cis linkage units in butadiene units are c-BD) (t-BD / c-BD) is 0.1 or less, the ratio (Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) is 2 or less, and the number average molecular weight A butadiene-based polymer having (Mn) of 10,000 to 1,000,000.