Method for producing catalyst composition and method for producing conjugated diene polymer

Abstract

The present invention relates to a method for producing a catalyst composition having improved catalytic activity by pretreating hydrogen-bonded lanthanum rare earth compounds and / or oligomer forms of lanthanum rare earth compounds, which cause a decrease in catalytic activity, and a method for producing a conjugated diene polymer using the catalyst composition produced thereby.

Description

[Technical field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0021076 filed on February 17, 2022, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a method for producing a catalyst composition for producing a conjugated diene polymer, and a method for producing a conjugated diene polymer using the same. [Background technology]

[0003] Recently, with the increasing interest in energy saving and environmental issues, there is a demand for automobiles with lower fuel consumption. As one method for achieving this, a method has been proposed in which the cis bond content and linearity of polybutadiene in a rubber composition for forming tires are increased, and the molecular weight distribution is narrowed.

[0004] Polybutadiene can be produced using a Ziegler-Natta catalyst, which is produced by activating an organic acid metal compound with an alkylaluminum and an alkylaluminum halide compound, and reacting the produced catalyst with 1,3-butadiene monomer to produce polybutadiene.

[0005] Here, the organic acid metal compound may be titanium-based, nickel-based, cobalt-based or lanthanum-based, and from the viewpoint of increasing the cis bond content and linearity of polybutadiene and narrowing the molecular weight distribution, lanthanum-based rare earth element compounds are mainly used.

[0006] Representative examples of the lanthanum-based rare earth element compounds include neodymium-based compounds, and a specific example is NdV (neodymium versatate), etc. This is activated through alkylation using an alkylaluminum compound and then halogenation using an alkylaluminum halide compound, and preforming may be performed by adding 1,3-butadiene monomer during the alkylation reaction to stabilize the catalyst.

[0007] Here, the same lanthanum rare earth compound such as NdV does not exist in the form of a single compound, but exists in the form of hydrogen bonds and / or oligomers due to moisture and aliphatic compounds used in the manufacturing process (Non-Patent Documents 1 and 2). However, when the hydrogen-bonded lanthanum rare earth compound and / or oligomer form of the lanthanum rare earth compound is directly alkylated, the alkylation takes a long time compared to when the lanthanum rare earth compound exists as a single compound, and the alkylation reaction is not fully carried out. When the lanthanum rare earth compound that is not fully alkylated is introduced into a halogenation reactor for carrying out the halogenation reaction, it causes a decrease in catalytic activity and also causes a problem of increasing contamination of the catalyst manufacturing equipment.

[0008] US Patent Publication No. 9056303 (Patent Document 1) discloses a method for producing a catalyst system using multiple alkylation reactors. In order to eliminate the drawbacks of producing a catalyst system in a batch mode, Patent Document 1 specifically specifies the type of reactor to prevent gel formation in the reactor during continuous production and to ensure the flexibility of the alkylating agent and rare earth salt that affect the catalytic activity, and adjusts the flow rate of the outlet of the catalyst system at the line outlet as necessary to remain within a residence time range suitable for the alkylation reaction and the chlorination reaction. In addition, Japanese Patent Publication No. 5072191 (Patent Document 2) discloses a method for producing a catalyst for conjugated diene polymerization by sequentially charging an alkylaluminum compound and an alkylaluminum hydride for the alkylation reaction. However, Patent Document 1 and Patent Document 2 only directly perform an alkylation reaction on a lanthanum compound during the production of a catalyst system and a catalyst for conjugated diene polymerization, and do not recognize the form of the lanthanum compound charged during the alkylation reaction and its effect on the catalytic activity. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] US9056303 B2 [Patent Document 2] JP5072191 B2 [Non-patent literature]

[0010] [Non-Patent Document 1] "A Highly Reactive and Monomeric Neodymium Ctalyst", Macromolecules 2002, 35, 13, 4875-4879(https: / / doi.org / 10.1021 / ma012123p) [Non-Patent Document 2] "Living and non-living Ziegler-Natta catalysts: electronic properties of active site", Polymer, Volume 44, Issue 21, October 2003, Pages 6555-6558(https: / / doi.org / 10.1016 / S0032-3861(03)00698-0) Summary of the Invention [Problem to be solved by the invention]

[0011] The problem to be solved by the present invention is to improve the catalytic activity in the continuous production of a catalyst composition for the polymerization of polybutadiene by pretreating hydrogen-bonded lanthanum rare earth compounds and / or oligomeric forms of lanthanum rare earth compounds, which cause a decrease in catalytic activity, prior to an alkylation reaction.

[0012] That is, in order to solve the problems mentioned in the Background of the Invention above, the present invention aims to provide a continuous production method for producing a catalyst composition having improved catalytic activity by pretreating hydrogen-bonded lanthanum rare earth compounds and / or oligomeric forms of lanthanum rare earth compounds, which cause a decrease in catalytic activity.

[0013] Another object of the present invention is to provide a method for producing a conjugated diene-based polymer having a high cis bond content, high linearity, and a narrow molecular weight distribution, by using a catalyst composition produced by the above-mentioned method for producing a catalyst composition. [Means for solving the problem]

[0014] In order to solve the above problems, the present invention provides a method for producing a catalyst composition and a method for producing a conjugated diene-based polymer.

[0015] (1) The present invention provides a method for preparing a catalyst composition, comprising: a pretreatment step (S10) of pretreating a lanthanum rare earth compound to form a hydrogen bond, an oligomer, or a combination thereof; an alkylation reaction step (S20) of mixing and reacting the lanthanum rare earth compound pretreated in the step (S10) with an alkylating agent; and a halogenation reaction step (S30) of mixing and reacting the lanthanum rare earth compound alkylated in the step (S20) with a halogen compound, wherein the step (S20) is continuously performed in a plurality of reactors connected in series.

[0016] (2) The present invention provides the method for producing a catalyst composition according to the above (1), wherein the step (S10) is carried out by mixing and reacting a lanthanum rare earth compound with one or more trialkylaluminums selected from the group consisting of trimethylaluminum and triethylaluminum.

[0017] (3) The present invention provides the method for producing a catalyst composition according to the above (2), wherein the step (S10) is carried out before the alkylation reaction of the lanthanum rare earth compound with trialkylaluminum.

[0018] (4) The present invention provides a method for producing a catalyst composition according to any one of the above (1) to (3), wherein the lanthanum rare earth compound is a neodymium compound represented by the following chemical formula 1:

[0019] [ka]

[0020] In the above formula 1, R 1 ~R 3 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 1 ~R 3 But it's not all hydrogen.

[0021] (5) The present invention is directed to any one of the above (1) to (4), wherein the lanthanum rare earth compound is Nd(2-ethylhexanoate)3, Nd(2,2-dimethyldecanoate)3, Nd(2,2-diethyldecanoate)3, Nd(2,2-dipropyldecanoate)3, Nd(2,2-dibutyldecanoate)3, Nd(2,2-dihexyldecanoate)3, Nd(2, 2-dioctyldecanoate)3, Nd(2-ethyl-2-propyldecanoate)3, Nd(2-ethyl-2-butyldecanoate)3, Nd(2-ethyl-2-hexyldecanoate)3, Nd(2-propyl-2-butyldecanoate)3, Nd(2-propyl-2-hexyldecanoate)3, Nd(2-propyl-2-isopropyldecanoate)3, Nd(2-butyl -2-Hexyldecanoate)3, Nd(2-Hexyl-2-octyldecanoate)3, Nd(2,2-Diethyloctanoate)3, Nd(2,2-Dipropyloctanoate)3, Nd(2,2-Dibutyloctanoate)3, Nd(2,2-Dihexyloctanoate)3, Nd(2-Ethyl-2-propyloctanoate)3, Nd(2-Ethyl-2-hexyloctanoate The present invention provides a method for producing a catalyst composition, the catalyst composition being one or more selected from the group consisting of Nd(2,2-diethylnonanoate)3, Nd(2,2-dipropylnonanoate)3, Nd(2,2-dibutylnonanoate)3, Nd(2,2-dihexylnonanoate)3, Nd(2-ethyl-2-propylnonanoate)3 and Nd(2-ethyl-2-hexylnonanoate)3.

[0022] (6) The present invention provides a method for producing a catalyst composition according to any one of the above (1) to (5), wherein the alkylating agent is an alkylaluminum compound represented by the following chemical formula 2: [Chemical formula 2] AlR 4 R 5 R 6 In the above formula 2, R 4 ~R 6 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 4 ~R6 is not all hydrogen, R 4 ~R 6 When all of are alkyl groups, the alkyl groups have 3 to 12 carbon atoms.

[0023] (7) The present invention provides a method for producing a catalyst composition according to any one of the above (1) to (6), wherein the alkylating agent is a dialkylaluminum hydride.

[0024] (8) The present invention provides a method for producing a catalyst composition according to any one of (1) to (7), wherein the pretreatment reaction in step (S10), the alkylation reaction in step (S20), or the pretreatment reaction in step (S10) and the alkylation reaction in step (S20) are carried out using a conjugated diene monomer.

[0025] (9) The present invention provides a method for producing a catalyst composition according to any one of the above items (1) to (8), wherein the halogen compound is at least one selected from the group consisting of alkylaluminum halides represented by the following chemical formula 3 and alkylaluminum sesquihalides represented by the following chemical formula 4: [Chemical formula 3] AlR 7 R 8 R 9 In the above formula 3, R 7 ~R 9 are each independently a halogen group or an alkyl group having 1 to 12 carbon atoms, and R 7 ~R 9 are not all halogen groups,

[0026] [ka]

[0027] In the above Chemical Formula 4, R 10 ~R 12 are each independently an alkyl group having 1 to 12 carbon atoms, and X1 to X3 are each independently a halogen group.

[0028] (10) The present invention provides a method for producing a catalyst composition according to any one of the above (1) to (9), wherein the halogen compound is at least one selected from the group consisting of dialkylaluminum halides and alkylaluminum sesquihalides.

[0029] (11) The present invention provides the method for producing a catalyst composition according to any one of (1) to (10), wherein the steps (S10), (S20) and (S30) are each carried out in separate reactors connected in series.

[0030] (12) The present invention provides a method for producing a catalyst composition according to any one of the above (1) to (11), wherein the steps (S10), (S20) and (S30) are carried out continuously.

[0031] (13) The present invention provides the method for producing a catalyst composition according to any one of the above (1) to (12), wherein the alkylating agent is divided and charged into the plurality of reactors connected in series.

[0032] (14) The present invention provides a method for producing a conjugated diene polymer, comprising the step (S100) of polymerizing a conjugated diene monomer in the presence of a catalyst composition produced by the method for producing a catalyst composition according to any one of (1) to (13) above, in a hydrocarbon solvent, to produce an active polymer.

[0033] (15) The present invention provides a conjugated diene polymer produced by the method for producing a conjugated diene polymer according to (14) above.

[0034] (16) The present invention provides a rubber composition containing the conjugated diene polymer according to (15) above. Effect of the Invention

[0035] The catalyst composition produced by the method for producing a catalyst composition of the present invention has excellent catalytic activity since it is produced by pretreating hydrogen-bonded lanthanum rare earth compounds and / or oligomer forms of lanthanum rare earth compounds, which cause a decrease in catalytic activity, prior to the alkylation reaction.

[0036] According to the method for producing a catalyst composition of the present invention, it is possible to continuously produce a catalyst composition, thereby improving the productivity of the catalyst composition and the conjugated diene-based polymer using the same, and ensuring more uniform quality.

[0037] The conjugated diene polymer produced by the method for producing a conjugated diene polymer of the present invention has a low content of lanthanum-based rare earth elements remaining in the conjugated diene polymer due to its high catalytic activity, a high content and linearity of cis bonds, and a narrow molecular weight distribution, and when applied to a rubber composition, it exhibits excellent wear resistance and fuel economy. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] The present invention will now be described in more detail to aid in understanding the present invention.

[0039] The terms and words used in the description of the present invention and the claims should not be interpreted in a limited manner to their ordinary or dictionary meanings, but should be interpreted in a manner that is consistent with the technical idea of ​​the present invention, based on the principle that the inventors can appropriately define the concepts of terms in order to best describe their invention.

[0040] Method for producing catalyst composition The present invention provides a method for producing a catalyst composition. The catalyst composition produced by the method for producing a catalyst composition may be a catalyst composition for polymerization of a conjugated diene-based polymer.

[0041] According to one embodiment of the present invention, the method for preparing the catalytic composition includes a pretreatment step (S10) of pretreating a lanthanum rare earth compound to form a hydrogen bond, an oligomer, or a combination thereof; an alkylation reaction step (S20) of mixing and reacting the lanthanum rare earth compound pretreated in the hydrogen bond, oligomer, or combination thereof in the step (S10) with an alkylating agent; and a halogenation reaction step (S30) of mixing and reacting the lanthanum rare earth compound alkylated in the step (S20) with a halogen compound, wherein the step (S20) may be continuously performed in a plurality of reactors connected in series.

[0042] As described in the Background Art of the present invention, lanthanum rare earth compounds do not exist in the form of a single compound, but in the form of hydrogen bonds and / or oligomers due to moisture and aliphatic compounds used in the manufacturing process (see Non-Patent Documents 1 and 2). However, when the hydrogen-bonded lanthanum rare earth compounds and / or oligomers of lanthanum rare earth compounds are directly alkylated, the alkylation takes a long time compared to when the lanthanum rare earth compounds exist as a single compound, and the alkylation reaction is not fully carried out. When the lanthanum rare earth compounds that are not fully alkylated are introduced into a halogenation reactor for carrying out the halogenation reaction, it causes a decrease in catalytic activity and also causes a problem of increasing contamination of the catalyst manufacturing equipment. However, the manufacturing method of the catalyst composition according to the present invention can improve the catalytic activity by pretreating the hydrogen-bonded lanthanum rare earth compounds and / or oligomers of lanthanum rare earth compounds in the step (S10) before the alkylation reaction. Here, the pretreatment may include minimizing or even removing hydrogen-bonded lanthanum rare earth compounds and / or oligomeric forms of lanthanum rare earth compounds prior to the alkylation reaction.

[0043] According to one embodiment of the present invention, the step (S10) may be carried out by mixing and reacting a lanthanum rare earth compound with one or more trialkylaluminums selected from the group consisting of trimethylaluminum and triethylaluminum. It is known that trimethylaluminum and triethylaluminum can be used as alkylating agents in alkylation reactions. However, when trimethylaluminum and triethylaluminum are used simply as alkylating agents, rather than for the purpose of carrying out the pretreatment reaction in the step (S10) as in the present invention, the alkylation reaction of the lanthanum rare earth compound can only be induced according to the purpose, which means that the alkylation reaction takes a long time and causes a problem that the alkylation reaction is not carried out sufficiently. From this perspective, the step (S10) may be carried out before the alkylation reaction of the lanthanum rare earth compound with one or more trialkylaluminums selected from the group consisting of trimethylaluminum and triethylaluminum is carried out. Meanwhile, trialkylaluminum and / or dialkylaluminum hydrides usable as alkylating agents other than trimethylaluminum and triethylaluminum cannot sufficiently induce hydrogen bonding, oligomer formation, or a combination thereof in the pretreatment reaction of the lanthanum rare earth element compound, and are therefore not suitable as trialkylaluminum compounds for the pretreatment reaction in the (S10) step.

[0044] According to an embodiment of the present invention, the (S10) step may be carried out by adding one or more trialkylaluminums selected from the group consisting of trimethylaluminum and triethylaluminum in a molar ratio of 1 mol or more, 2 mol or more, 3 mol or more, 4 mol or more, 5 mol or more, 6 mol or more, 7 mol or more, 8 mol or more, 9 mol or more, or 10 mol or more, or may be carried out by adding one or more trialkylaluminums selected from the group consisting of trimethylaluminum and triethylaluminum in a molar ratio of 20 mol or less, 19 mol or less, 18 mol or less, 17 mol or less, 16 mol or less, 15 mol or less, 14 mol or less, 13 mol or less, 12 mol or less, 11 mol or less, or 10 mol or less, relative to 1 mol of the lanthanum rare earth compound.

[0045] According to one embodiment of the present invention, the (S10) step may be carried out at a temperature of -20°C or higher, -15°C or higher, or -10°C or higher, and may be carried out at a temperature of 40°C or lower, 35°C or lower, 30°C or lower, 25°C or lower, or 20°C or lower.

[0046] According to one embodiment of the present invention, the (S10) step may be performed for 10 minutes or more, 15 minutes or more, 20 minutes or more, 25 minutes or more, or 30 minutes or more, and may be performed for 1 hour or less, 50 minutes or less, 40 minutes or less, or 30 minutes or less.

[0047] According to one embodiment of the present invention, in step (S10), the efficiency of the pretreatment reaction of the lanthanum rare earth compound to form hydrogen bonds, oligomers, or a combination thereof can be further improved by adjusting the molar ratio between the lanthanum rare earth compound and one or more trialkylaluminums selected from the group consisting of trimethylaluminum and triethylaluminum, the reaction temperature, and the reaction time.

[0048] According to an embodiment of the present invention, the lanthanum rare earth compound may be a neodymium compound, and specific examples thereof include neodymium carboxylates (e.g., neodymium acetate, neodymium acrylate, neodymium methacrylate, neodymium gluconate, neodymium citrate, neodymium fumarate, neodymium lactate, neodymium maleate, neodymium oxalate, neodymium 2-ethylhexanoate, neodymium neodecanoate, etc.); organic phosphates (e.g., neodymium dibutyl phosphate, neodymium dipentyl phosphate, neodymium dihexyl phosphate, etc.); neodymium phosphate, neodymium diheptyl phosphate, neodymium dioctyl phosphate, neodymium bis(1-methylheptyl)phosphate, neodymium bis(2-ethylhexyl)phosphate, or neodymium didecyl phosphate; organic phosphonates (e.g., neodymium butyl phosphonate, neodymium pentyl phosphonate, neodymium hexyl phosphonate, neodymium heptyl phosphonate, neodymium octyl phosphonate, neodymium (1-methylheptyl)phosphonate, neodymium (2-ethylhexyl)phosphonate, neodymium decyl phosphonate, neodymium dodecylphosphonate or neodymium octadecylphosphonate; organic phosphinates (e.g. neodymium butylphosphinate, neodymium pentylphosphinate, neodymium hexylphosphinate, neodymium heptylphosphinate, neodymium octylphosphinate, neodymium (1-methylheptyl)phosphinate or neodymium (2-ethylhexyl)phosphinate); carbamates (e.g. neodymium dimethylcarbamate, neodymium diethylcarbamate, neodymium diisopropylcarbamate); salts, such as neodymium dibutylcarbamate or neodymium dibenzylcarbamate; dithiocarbamates (such as neodymium dimethyldithiocarbamate, neodymium diethyldithiocarbamate, neodymium diisopropyldithiocarbamate or neodymium dibutyldithiocarbamate); xanthogenates (such as neodymium methylxanthogenate, neodymium ethylxanthogenate, neodymium isopropylxanthogenate, neodymium butylxanthogenate, or neodymium benzylxanthogenate);β-diketonates (such as neodymium acetylacetonate, neodymium trifluoroacetylacetonate, neodymium hexafluoroacetylacetonate or neodymium benzoylacetonate); alkoxides or aryloxides (such as neodymium methoxide, neodymium ethoxide, neodymium isopropoxide, neodymium phenoxide or neodymium nonylphenoxide); halides or pseudohalides (such as neodymium fluoride, neodymium chloride, neodymium fluoride, neodymium iodide, neodymium cyanide, neodymium cyanate, neodymium thiocyanate or neodymium tetrahydrofuran); neodymium azide, etc.); oxyhalides (e.g., neodymium oxyfluoride, neodymium oxychloride, or neodymium oxybromide, etc.); or organic neodymium compounds containing one or more rare earth element-carbon bonds (e.g., Cp3Ln, Cp2LnR, Cp2LnCl, CpLnCl2, CpLn(cyclooctatetraene), (C5Me5)2LnR, LnR3, Ln(allyl)3, or Ln(allyl)2Cl, etc., in which Ln is a rare earth metal element and R is a hydrocarbyl group), etc., and any one or a mixture of two or more of these may be included;

[0049] According to an embodiment of the present invention, the lanthanide rare earth compound may be a neodymium compound represented by the following Chemical Formula 1:

[0050] [ka]

[0051] In the above formula 1, R 1 ~R 3 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 1 ~R 3 may not all be hydrogen. 1 is an alkyl group having 4 to 12 carbon atoms, and R 2 and R 3 are each independently a hydrogen atom or an alkyl group having 2 to 8 carbon atoms, and R 2and R 3 may not all be hydrogen. 1 is an alkyl group having 6 to 8 carbon atoms, and R 2 and R 3 are each independently a hydrogen atom or an alkyl group having 2 to 6 carbon atoms, and R 2 and R 3 does not have to be all hydrogen.

[0052] According to one embodiment of the present invention, the lanthanum rare earth compound is Nd(2-ethylhexanoate)3, (neodymium versatate), Nd(2,2-dimethyldecanoate)3, Nd(2,2-diethyldecanoate)3, Nd(2,2-dipropyldecanoate)3, Nd(2,2-dibutyldecanoate)3, Nd(2,2-dihexyldecanoate)3, Nd(2 ,2-dioctyldecanoate)3, Nd(2-ethyl-2-propyldecanoate)3, Nd(2-ethyl-2-butyldecanoate)3, Nd(2-ethyl-2-hexyldecanoate)3, Nd(2-propyl-2-butyldecanoate)3, Nd(2-propyl-2-hexyldecanoate)3, Nd(2-propyl-2-isopropyldecanoate)3, Nd(2 -butyl-2-hexyldecanoate)3, Nd(2-hexyl-2-octyldecanoate)3, Nd(2,2-diethyloctanoate)3, Nd(2,2-dipropyloctanoate)3, Nd(2,2-dibutyloctanoate)3, Nd(2,2-dihexyloctanoate)3, Nd(2-ethyl-2-propyloctanoate)3, Nd(2-ethyl-2- The compound may be one or more selected from the group consisting of Nd(2,2-diethylnonanoate)3, Nd(2,2-dipropylnonanoate)3, Nd(2,2-dibutylnonanoate)3, Nd(2,2-dihexylnonanoate)3, Nd(2-ethyl-2-propylnonanoate)3 and Nd(2-ethyl-2-hexylnonanoate)3.

[0053] According to one embodiment of the present invention, the neodymium compound contains a carboxylate ligand containing an alkyl group of various lengths having two or more carbon atoms as a substituent at the α-position, thereby inducing a three-dimensional change around the neodymium central metal and blocking the phenomenon of entanglement between compounds, thereby suppressing oligomerization during polymerization of a conjugated diene polymer using the catalyst composition. In addition, such a neodymium-based compound has the effect of reducing the ratio of neodymium located in the central portion, which is difficult to convert to catalytically active species, due to its high solubility in solvents, and thus increasing the conversion rate to catalytically active species.

[0054] According to one embodiment of the present invention, the solubility of the neodymium compound may be about 60 parts by weight or more per 100 parts by weight of the non-polar solvent at room temperature (25° C.). The solubility of the neodymium-based compound means the degree to which it is dissolved cleanly without a suspension phenomenon, and such high solubility can result in excellent catalytic activity.

[0055] According to one embodiment of the present invention, the (S10) step may be carried out by including a conjugated diene monomer. This is to form a pre-polymerized or premixed catalyst composition by pre-mixing a conjugated diene monomer used in the polymerization reaction of a conjugated diene polymer using the catalyst composition prepared according to the present invention with the catalyst composition, which can further improve the activity of the catalyst composition and stabilize the active polymer produced. The "pre-polymerization" may mean that a small amount of a conjugated diene monomer such as 1,3-butadiene is added to the catalyst composition containing a neodymium compound, an alkylating agent, and a halogen compound, i.e., in order to reduce the possibility of generating active species of various catalyst compositions in the catalyst system, and pre-polymerization is performed in the catalyst composition system together with the addition of 1,3-butadiene. Also, "premix" may mean a state in which polymerization is not performed in the catalyst composition system and each compound is uniformly mixed.

[0056] According to an embodiment of the present invention, the conjugated diene monomer that may be added in step (S10) may be 1,3-butadiene or a derivative thereof, such as 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, or 2-ethyl-1,3-butadiene, or may be 2-methyl-1,3-pentadiene, 1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 1,3-hexadiene, or 2,4-hexadiene.

[0057] According to an embodiment of the present invention, when the step (S10) is carried out including a conjugated diene monomer, the conjugated diene monomer may be added in a molar ratio of 1 mole or more, 5 moles or more, 10 moles or more, 15 moles or more, or 20 moles or more, per mole of the lanthanum rare earth element compound, or may be added in a molar ratio of 100 moles or less, 90 moles or less, 80 moles or less, 70 moles or less, 60 moles or less, or 50 moles or less.

[0058] According to one embodiment of the present invention, step (S20) is a step for carrying out an alkylation reaction on a lanthanum rare earth compound, and may be carried out by mixing and reacting the lanthanum rare earth compound pretreated in step (S10) to form a hydrogen bond, an oligomer, or a combination thereof with an alkylating agent.

[0059] According to one embodiment of the present invention, the alkylating agent may act as a cocatalyst as an organometallic compound capable of transferring a hydrocarbyl group to another metal. The alkylating agent may be an organometallic compound that is soluble in the polymerization solvent and contains a metal-carbon bond, such as an organoaluminum compound, an organomagnesium compound, or an organolithium compound.

[0060] According to one embodiment of the present invention, the alkylating agent may be an organoaluminum compound, and specific examples thereof include alkylaluminum such as tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-t-butylaluminum, tripentylaluminum, trihexylaluminum, tricyclohexylaluminum, and trioctylaluminum; diethylaluminum hydride, di-n-propylaluminum hydride, diisopropylaluminum hydride, di-n-butylaluminum hydride, diisobutylaluminum hydride (DIBAH), di-n-octylaluminum hydride, diphenylaluminum hydride, di-p-tolylaluminum hydride, dibenzylaluminum hydride, phenylethylaluminum hydride, phenyl-n-propylaluminum hydride, phenylisopropylaluminum hydride, phenyl-n-butylaluminum hydride, and phenylisobutylaluminum hydride. aluminum hydride, dihydrocarbyl aluminum hydrides such as phenyl-n-octylaluminum hydride, p-tolylethyl aluminum hydride, p-tolyl-n-propyl aluminum hydride, p-tolylisopropyl aluminum hydride, p-tolyl-n-butyl aluminum hydride, p-tolylisobutyl aluminum hydride, p-tolyl-n-octylaluminum hydride, benzylethyl aluminum hydride, benzyl-n-propyl aluminum hydride, benzylisopropyl aluminum hydride, benzyl-n-butyl aluminum hydride, benzylisobutyl aluminum hydride or benzyl-n-octylaluminum hydride; hydrocarbyl aluminum dihydrides such as ethyl aluminum dihydride, n-propyl aluminum dihydride, isopropyl aluminum dihydride, n-butyl aluminum dihydride, isobutyl aluminum dihydride or n-octylaluminum dihydride, and the like.

[0061] According to one embodiment of the present invention, the alkylating agent is preferably an alkylaluminum compound from the viewpoint of controlling catalytic reactions and side reactions caused by the lanthanum rare earth compound pretreated in step (S10) with hydrogen bonding, oligomer form, or a combination thereof. As a specific example, the alkylating agent may be an alkylaluminum compound represented by the following formula 2:

[0062] [Chemical formula 2] AlR 4 R 5 R 6

[0063] In the above formula 2, R 4 ~R 6 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 4 ~R 6 is not all hydrogen, R 4 ~R 6 When all of R are alkyl groups, the number of carbon atoms in the alkyl group may be 3 to 12. 4 ~R 6 are each independently a hydrogen atom or an alkyl group having 3 to 8 carbon atoms, and R 4 ~R 6 is not all hydrogen, R 4 ~R 6 When all of are alkyl groups, the number of carbon atoms in the alkyl group may be 3 to 6. As a further specific example, in the above Chemical Formula 2, R 4 ~R 6 are each independently a hydrogen atom or an alkyl group having 3 to 6 carbon atoms, and R 4 ~R 6 does not have to be all hydrogen.

[0064] According to one embodiment of the present invention, the alkylating agent may be a dialkylaluminum hydride from the viewpoint of controlling the catalytic reaction and side reaction of the lanthanum rare earth compound pretreated in the hydrogen bond, oligomer form, or a combination thereof in the step (S10), and the type of the dialkylaluminum hydride is as described above. As a specific example, the alkylating agent may be diisobutylaluminum hydride.

[0065] According to one embodiment of the present invention, the alkylating agent may include two or more alkylaluminum compounds. As a specific example, the alkylating agent may include two or more selected from the group consisting of dialkylaluminum hydrides and trialkylaluminums. As a more specific example, the alkylating agent may include one or more dialkylaluminum hydrides and one or more trialkylaluminums, and as a more specific example, the alkylating agent may include diisobutylaluminum hydride and triisobutylaluminum.

[0066] According to one embodiment of the present invention, the (S20) step may be carried out by adding an alkylating agent in a molar ratio of 1 mole or more, 2 moles or more, 3 moles or more, 4 moles or more, 5 moles or more, 6 moles or more, 7 moles or more, 8 moles or more, 9 moles or more, 10 moles or more, 11 moles or more, 12 moles or more, 13 moles or more, 14 moles or more, or 15 moles or more, or in a molar ratio of 30 moles or less, 29 moles or less, 28 moles or less, 27 moles or less, 26 moles or less, 25 moles or less, 24 moles or less, 23 moles or less, 22 moles or less, 21 moles or less, 20 moles or less, 19 moles or less, 18 moles or less, 17 moles or less, 16 moles or less, or 15 moles or less, based on 1 mole of the lanthanum rare earth compound pretreated in the hydrogen bond, oligomer form, or a combination thereof in the (S10) step.

[0067] According to one embodiment of the present invention, the (S20) step may be performed at a temperature of -20°C or higher, -15°C or higher, -10°C or higher, or -5°C or higher, and may be performed at a temperature of 40°C or lower, 35°C or lower, 30°C or lower, 25°C or lower, or 20°C or lower.

[0068] According to one embodiment of the present invention, the (S20) step may be performed for 10 minutes or more, 15 minutes or more, 20 minutes or more, 25 minutes or more, or 30 minutes or more, and may be performed for 2 hours or less, 1 hour and 30 minutes or less, 1 hour or less, 50 minutes or less, 40 minutes or less, or 30 minutes or less.

[0069] According to one embodiment of the present invention, in step (S20), the catalytic activity can be further improved by adjusting the molar ratio of the lanthanum rare earth compound pretreated in step (S10) to the alkylating agent, the reaction temperature, and the reaction time.

[0070] According to one embodiment of the present invention, the step (S20) may be carried out using a conjugated diene monomer for the same purpose as the step (S10). Here, when the step (S20) is carried out using a conjugated diene monomer, it may be carried out separately from or simultaneously with the step (S10).

[0071] According to an embodiment of the present invention, when the step (S20) is carried out including a conjugated diene monomer, the conjugated diene monomer may be added in a molar ratio of 1 mol or more, 5 mol or more, 10 mol or more, 15 mol or more, or 20 mol or more per mol of the lanthanum rare earth compound pretreated in the step (S10) to form a hydrogen bond, an oligomer, or a combination thereof, and may be added in a molar ratio of 100 mol or less, 90 mol or less, 80 mol or less, 70 mol or less, 60 mol or less, or 50 mol or less.

[0072] According to one embodiment of the present invention, the (S20) step may be continuously performed in a plurality of reactors connected in series. In this case, the alkylation reaction is performed in a plurality of reactors connected in series, so that the activity of the catalyst composition can be further improved by performing the alkylation reaction sufficiently. Here, the alkylating agent may be introduced only into the first reactor of the plurality of reactors connected in series to perform the (S20) step, or may be divided and introduced into the plurality of reactors connected in series to perform the (S20) step. When the alkylating agent is divided and introduced into the plurality of reactors, the reactor into which the alkylating agent is introduced may be selected as necessary. In addition, the alkylating agent divided and introduced into the plurality of reactors connected in series may be the same or different in type.

[0073] According to one embodiment of the present invention, the flow of reactants in the multiple reactors connected in series in step (S20) may be independently performed in a top-down manner or a bottom-up manner.

[0074] According to an embodiment of the present invention, at least one of the reactors connected in series in step (S20) may include a pipe-type reactor equipped with a line mixer. In this case, the reactants can be continuously mixed by being retained in the pipe-type reactor connected between the reactors connected in series, and the alkylation reaction can be more efficiently performed.

[0075] According to an embodiment of the present invention, step (S30) is a step for carrying out a halogenation reaction on the lanthanum rare earth compound alkylated in step (S20), and may be carried out by mixing and reacting the lanthanum rare earth compound alkylated in step (S20) with a halogen compound.

[0076] According to an embodiment of the present invention, the halogen compound may be a halogen element, an interhalogen compound, a hydrogen halide, an organic halide, a non-metal halide, a metal halide, or an organic metal halide.

[0077] According to one embodiment of the present invention, the halogen element may be fluorine, chlorine, bromine or iodine.

[0078] According to an embodiment of the present invention, the interhalogen compound may be iodine monochloride, iodine monobromide, iodine trichloride, iodine pentafluoride, iodine monofluoride, or iodine trifluoride, etc.

[0079] According to one embodiment of the present invention, the hydrogen halide may be hydrogen fluoride, hydrogen chloride, hydrogen bromide or hydrogen iodide.

[0080] According to one embodiment of the present invention, the organic halide is t-butyl chloride (t-BuCl), t-butyl bromide, allyl chloride, allyl bromide, benzyl chloride, benzyl bromide, chloro-di-phenylmethane, bromo-di-phenylmethane, triphenylmethyl chloride, triphenylmethyl bromide, benzylidene chloride, benzylidene bromide, methyltrichlorosilane, phenyltrichlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, trimethylchlorosilane (TMSCl), benzoyl chloride, benzoyl bromide, propionyl chloride, propionyl bromide, methylchloroformate, methylbromoformate, iodomethane, diiodomethane, triiodomethane ("iodomethane"). The iodide may be, for example, tetraiodomethane, 1-iodopropane, 2-iodopropane, 1,3-diiodopropane, t-butyl iodide, 2,2-dimethyl-1-iodopropane (also referred to as "neopentyl iodide"), allyl iodide, iodobenzene, benzyl iodide, diphenylmethyl iodide, triphenylmethyl iodide, benzylidene iodide (also referred to as "benzal iodide"), trimethylsilyliodide, triethylsilyliodide, triphenylsilyliodide, dimethyldiiodosilane, diethyldiiodosilane, diphenyldiiodosilane, methyltriiodosilane, ethyltriiodosilane, phenyltriiodosilane, benzoyl iodide, propionyl iodide, or methyl iodoformate.

[0081] According to one embodiment of the present invention, the non-metal halide may be phosphorus trichloride, phosphorus tribromide, phosphorus pentachloride, phosphorus oxychloride, phosphorus oxybromide, boron trifluoride, boron trichloride, boron tribromide, silicon tetrafluoride, silicon tetrachloride (SiCl4), silicon tetrabromide, arsenic trichloride, arsenic tribromide, selenium tetrachloride, selenium tetrabromide, tellurium tetrachloride, tellurium tetrabromide, silicon tetraiodide, arsenic triiodide, tellurium tetraiodide, boron triiodide, phosphorus triiodide, phosphorus oxyiodide, or selenium tetraiodide, etc.

[0082] According to an embodiment of the present invention, the metal halide may be tin tetrachloride, tin tetrabromide, aluminum trichloride, aluminum tribromide, antimony trichloride, antimony pentachloride, antimony tribromide, aluminum trifluoride, gallium trichloride, gallium tribromide, gallium trifluoride, indium trichloride, indium tribromide, indium trifluoride, titanium tetrachloride, titanium tetrabromide, zinc dichloride, zinc dibromide, zinc difluoride, aluminum triiodide, gallium triiodide, indium triiodide, titanium tetraiodide, zinc diiodide, germanium tetraiodide, tin tetraiodide, tin diiodide, antimony triiodide, or magnesium diiodide.

[0083] According to one embodiment of the present invention, the organometallic halide may be an alkylaluminum halide or an alkylaluminum sesquihalide.Specific examples of the organometallic halide include dimethylaluminum chloride, diethylaluminum chloride, dimethylaluminum bromide, diethylaluminum bromide, dimethylaluminum fluoride, diethylaluminum fluoride, methylaluminum dichloride, ethylaluminum dichloride, methylaluminum dibromide, ethylaluminum dibromide, methylaluminum difluoride, ethylaluminum difluoride, methylaluminum sesquichloride, ethylaluminum sesquichloride (EASC), isobutylaluminum sesquichloride, methylmagnesium chloride, methylmagnesium bromide, ethylmagnesium chloride, ethylmagnesium bromide, n-butylmagnesium chloride, n-butylmagnesium bromide, phenylmagnesium chloride, phenylmagnesium bromide, benzylmagnesium chloride, trimethyltin chloride, trimethyltin bromide, triethyltin chloride, triethyltin bromide, iodide, di-t-butyltin dichloride, di-t-butyltin dibromide, di-n-butyltin dichloride, di-n-butyltin dibromide, tri-n-butyltin chloride, tri-n-butyltin bromide, methylmagnesium iodide, dimethylaluminum iodide, diethylaluminum iodide, di-n-butylaluminum iodide, diisobutylaluminum iodide, di-n-octylaluminum iodide, methylaluminum diiodide, ethylaluminum diiodide, n-butylaluminum aluminum diiodide, isobutylaluminum diiodide, methylaluminum sesquiiodide, ethylaluminum sesquiiodide, isobutylaluminum sesquiiodide, ethylmagnesium iodide, n-butylmagnesium iodide, isobutylmagnesium iodide, phenylmagnesium iodide, benzylmagnesium iodide, trimethyltin iodide, triethyltin iodide, tri-n-butyltin iodide, di-n-butyltin diiodide, or di-t-butyltin diiodide.

[0084] According to one embodiment of the present invention, the halogen compound may be at least one selected from the group consisting of alkylaluminum halides represented by the following formula 3 and alkylaluminum sesquihalides represented by the following formula 4, in order to improve catalytic activity and thereby reactivity.

[0085] [Chemical formula 3] AlR 7 R 8 R 9

[0086] In the above formula 3, R 7 ~R 9 are each independently a halogen group or an alkyl group having 1 to 12 carbon atoms, and R 7 ~R 9 may not all be halogen groups. 7 ~R 9 are each independently a halogen group or an alkyl group having 1 to 6 carbon atoms, and R 7 ~R 9 may not all be halogen groups. 7 and R 8 are each independently an alkyl group having 1 to 4 carbon atoms; R 9 may be a halogen group.

[0087] [ka]

[0088] In the above Chemical Formula 4, R 10 ~R 12 may each independently be an alkyl group having 1 to 12 carbon atoms, and X1 to X3 may each independently be a halogen group. 10 ~R 12 may each independently be an alkyl group having 1 to 6 carbon atoms. 10 ~R 12may each independently be an alkyl group having 1 to 4 carbon atoms.

[0089] According to one embodiment of the present invention, the halogen compound may be at least one selected from the group consisting of dialkylaluminum halides and alkylaluminum sesquihalides in order to control catalytic reactions and side reactions caused by the lanthanum rare earth compound pretreated in step (S10) with hydrogen bonding, oligomer form, or a combination thereof, and the types of dialkylaluminum halides and alkylaluminum sesquihalides are as described above. As a specific example, the dialkylaluminum halide may be diethylaluminum chloride, and the alkylaluminum sesquihalide may be ethylaluminum sesquichloride.

[0090] According to one embodiment of the present invention, the step (S30) may be performed by adding a molar ratio of 0.1 mol or more, 0.5 mol or more, 1.0 mol or more, 1.5 mol or more, 2.0 mol or more, 2.5 mol or more, or 3.0 mol or more of a halogen compound relative to 1 mol of the lanthanum rare earth compound pretreated in the hydrogen bond, oligomer form, or a combination thereof in the step (S10), or may be performed by adding a molar ratio of 5.0 mol or less, 4.5 mol or less, 4.0 mol or less, 3.5 mol or less, or 3.0 mol or less.

[0091] According to one embodiment of the present invention, the (S30) step may be carried out at a temperature of -20°C or higher, -15°C or higher, or -10°C or higher, and may be carried out at a temperature of 40°C or lower, 35°C or lower, 30°C or lower, 25°C or lower, or 20°C or lower.

[0092] According to one embodiment of the present invention, the (S30) step may be performed for 10 minutes or more, 15 minutes or more, 20 minutes or more, 25 minutes or more, or 30 minutes or more, and may be performed for 1 hour or less, 50 minutes or less, 40 minutes or less, or 30 minutes or less.

[0093] According to one embodiment of the present invention, in step (S30), the catalytic activity can be further improved by adjusting the molar ratio of the lanthanum rare earth compound pretreated in step (S10) to the halogen compound, the reaction temperature, and the reaction time.

[0094] According to an embodiment of the present invention, the steps (S10) to (S30) may be carried out in an organic solvent. The organic solvent may be a non-polar solvent that is not reactive with the components of the catalyst composition. As a specific example, the organic solvent may be a linear, branched or cyclic aliphatic hydrocarbon having 5 to 20 carbon atoms, such as n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, isopentane, isohexane, isooctane, 2,2-dimethylbutane, cyclopentane, cyclohexane, methylcyclopentane or methylcyclohexane; a mixed solvent of aliphatic hydrocarbons having 5 to 20 carbon atoms, such as petroleum ether, petroleum spirits, or kerosene; or an aromatic hydrocarbon solvent, such as benzene, toluene, ethylbenzene, or xylene. As a more specific example, the organic solvent may be the linear, branched or cyclic aliphatic hydrocarbon having 5 to 20 carbon atoms or a mixed solvent of aliphatic hydrocarbons, and preferably, n-hexane, cyclohexane, or a mixture thereof.

[0095] According to one embodiment of the present invention, the steps (S10), (S20) and (S30) may be carried out in separate reactors connected in series, respectively. Therefore, in order to prepare a catalyst by the method for preparing a catalyst composition, at least one or more reactors for carrying out the step (S10), two or more reactors for carrying out the step (S20) and one or more reactors for carrying out the step (S30), totaling four or more reactors, are required.

[0096] According to one embodiment of the present invention, the steps (S10), (S20) and (S30) may be carried out continuously, i.e., the steps (S10), (S20) and (S30) may be carried out continuously in separate reactors connected in series, in which case the productivity of the catalyst composition and the conjugated diene-based polymer using the same may be improved and more uniform quality may be ensured.

[0097] According to one embodiment of the present invention, all steps of the method for preparing a catalyst composition, including steps (S10) to (S30), may be carried out at a temperature of -20°C or higher, -15°C or higher, -10°C or higher, or -5°C or higher, and may be carried out at a temperature of 40°C or lower, 35°C or lower, 30°C or lower, 25°C or lower, 20°C or lower, or 15°C or lower.

[0098] According to one embodiment of the present invention, all steps of the method for producing a catalyst composition including steps (S10) to (S30) may be carried out for 30 minutes or more, 35 minutes or more, 40 minutes or more, 45 minutes or more, 50 minutes or more, 55 minutes or more, 60 minutes or more, 65 minutes or more, or 70 minutes or more, and may be carried out for 2 hours or less, 1 hour 50 minutes or less, 1 hour 40 minutes or less, 1 hour 30 minutes or less, 1 hour 20 minutes or less, or 1 hour 10 minutes or less.

[0099] Method for producing conjugated diene polymer The present invention provides a method for producing a conjugated diene-based polymer.

[0100] According to an embodiment of the present invention, the method for producing a conjugated diene-based polymer may include a step (S100) of polymerizing a conjugated diene-based monomer in a hydrocarbon solvent in the presence of a catalyst composition prepared by the method for preparing a catalyst composition to produce an activated polymer.

[0101] According to an embodiment of the present invention, the conjugated diene monomer that may be added in step (S100) may be at least one selected from the group consisting of 1,3-butadiene, isoprene, 1,3-pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, and 2,4-hexadiene.

[0102] According to one embodiment of the present invention, the hydrocarbon solvent in step (S100) may be one or more selected from the group consisting of n-pentane, n-hexane, n-heptane, isooctane, cyclohexane, toluene, benzene and xylene.

[0103] According to one embodiment of the present invention, the catalyst composition may be a catalyst composition prepared by the above-mentioned method for preparing a catalyst composition, and the catalyst composition may be used in an amount of 0.03 mmol or more, 0.04 mmol or more, 0.05 mmol or more, or 0.06 mmol or more of the neodymium compound relative to a total of 100 g of the conjugated diene monomer, and may be used in an amount of 0.15 mmol or less, 0.14 mmol or less, 0.13 mmol or less, 0.12 mmol or less, 0.11 mmol or less, 0.10 mmol or less, 0.09 mmol or less, or 0.08 mmol or less.

[0104] According to one embodiment of the present invention, the polymerization in step (S100) may be carried out in a continuous polymerization reactor including at least two reactors or in a batch reactor, and may be a temperature-rise polymerization, an isothermal polymerization, or a constant temperature polymerization (adiabatic polymerization).

[0105] According to one embodiment of the present invention, the constant temperature polymerization means polymerization by the heat of reaction itself without adding any heat after adding a catalyst composition, the temperature increasing polymerization means increasing the temperature by adding any heat after adding a catalyst composition, and the isothermal polymerization means maintaining the temperature of the reactants constant by adding heat to increase the temperature or removing heat after adding a catalyst composition.

[0106] According to one embodiment of the present invention, the polymerization in step (S100) may be carried out using coordination anion polymerization, and the polymerization environment may be bulk polymerization, solution polymerization, suspension polymerization or emulsion polymerization, and a specific example may be solution polymerization.

[0107] According to one embodiment of the present invention, the polymerization in step (S100) may be carried out at a temperature of -20°C or more, -10°C or more, 0°C or more, 10°C or more, 20°C or more, 30°C or more, 40°C or more, 50°C or more, or 60°C or more, and may be carried out at a temperature of 200°C or less, 150°C or less, 120°C or less, or 90°C or less. Within this range, the polymerization reaction can be smoothly controlled and the cis-1,4 bond content of the resulting conjugated diene polymer can be ensured.

[0108] According to one embodiment of the present invention, the polymerization of the (S100) step may be carried out for 15 minutes or more, 20 minutes or more, 30 minutes or more, 40 minutes or more, 50 minutes or more, or 1 hour or more, and may be carried out for 3 hours or less, 2 hours and 30 minutes or less, or 2 hours or less.

[0109] According to an embodiment of the present invention, the conjugated diene-based polymer formed by polymerization in step (S100) may be an activated polymer including sites activated by a catalyst composition.

[0110] According to an embodiment of the present invention, the method may include reacting the activated polymer with a modifier (S200). The modifier may be a known modifier that can be used in the preparation of a conjugated diene-based polymer using a catalyst composition containing a lanthanum rare earth compound.

[0111] According to one embodiment of the present invention, the method for preparing the conjugated diene-based polymer may include a step of terminating the polymerization after preparing the activated polymer by further using an additive such as a reaction terminator for completing the polymerization reaction, such as polyoxyethylene glycol phosphate, or an antioxidant, such as 2,6-di-t-butyl-p-cresol. In addition, an additive for facilitating solution polymerization, such as a chelating agent, a dispersing agent, a pH regulator, an oxygen scavenger, or an oxygen scavenger, may be selectively further used together with the reaction terminator.

[0112] Conjugated diene polymer The present invention provides a conjugated diene-based polymer.

[0113] According to an embodiment of the present invention, the conjugated diene-based polymer may be prepared by the method for preparing a conjugated diene-based polymer, i.e., the conjugated diene-based polymer may be polymerized in the presence of a catalyst composition prepared by the method for preparing a catalyst composition described above.

[0114] According to an embodiment of the present invention, the conjugated diene polymer may include a conjugated diene monomer unit, which refers to a repeating unit formed by polymerization of a conjugated diene monomer.

[0115] According to one embodiment of the present invention, the conjugated diene-based polymer may contain 80% by weight or more, 85% by weight or more, 90% by weight or more, 95% by weight or more, or 100% by weight of 1,3-butadiene monomer units, and optionally may contain 20% by weight or less, 15% by weight or less, 10% by weight or less, or 5% by weight or less of other conjugated diene-based monomer units copolymerizable with the 1,3-butadiene monomer, and within this range, a decrease in the cis-1,4 bond content in the conjugated diene-based polymer may be prevented. The 1,3-butadiene monomer may be 1,3-butadiene or a derivative thereof, such as 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, or 2-ethyl-1,3-butadiene, and other conjugated diene monomers copolymerizable with the 1,3-butadiene may be 2-methyl-1,3-pentadiene, 1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 1,3-hexadiene, or 2,4-hexadiene.

[0116] According to one embodiment of the present invention, the conjugated diene-based polymer may be a conjugated diene-based polymer catalyzed from a catalyst composition containing a lanthanum rare earth element compound, i.e., the conjugated diene-based polymer may be a conjugated diene-based polymer containing an organometallic moiety activated from a catalyst composition containing a neodymium compound.

[0117] According to one embodiment of the present invention, the conjugated diene-based polymer has a weight average molecular weight (Mw) of 1.0×10 5 g / mol or more, 2.0×10 5 g / mol or more, 3.0×10 5 g / mol or more, 4.0×10 5 g / mol or more, 5.0×10 5 g / mol or more, 6.0×10 5 g / mol or more, 7.0×10 5 g / mol or more, 8.0×10 5 g / mol or greater or 9.0×10 5 g / mol or more, and 6 g / mol or less, 9.0×10 5g / mol or less, 8.0×10 5 g / mol or less, 7.0×10 5 g / mol or less, 6.0×10 5 g / mol or less, 5.0×10 5 g / mol or less, 4.0×10 5 g / mol or less, or 3.0×10 5 The conjugated diene polymer may have a number average molecular weight (Mn) of 1.0×10 5 g / mol or more, 2.0×10 5 g / mol or more, 3.0×10 5 g / mol or more, 4.0×10 5 g / mol or greater, or 5.0×10 5 g / mol or more, and 5 g / mol or less, 5.0×10 5 g / mol or less, 4.0×10 5 g / mol or less, 3.0×10 5 g / mol or less, 2.0×10 5 g / mol or less, or 1.0×10 5 Within this range, when applied to a rubber composition, the rubber composition has excellent tensile properties and excellent processability, which improves the workability of the rubber composition to facilitate kneading, and has the effect of providing the rubber composition with excellent mechanical properties and a good balance of physical properties.

[0118] According to an embodiment of the present invention, the conjugated diene-based polymer may have a molecular weight distribution (Mw / Mn) of 1.0 or more, 1.5 or more, 2.0 or more, 2.1 or more, 2.2 or more, or 2.3 or more, and may be 4.0 or less, 3.5 or less, 3.0 or less, or 2.5 or less. The molecular weight distribution may be calculated from the ratio (Mw / Mn) of the number average molecular weight (Mn) to the weight average molecular weight (Mw). Here, the number average molecular weight (Mn) is a common average of the molecular weights of individual polymers calculated by measuring the molecular weights of n polymer chains, calculating the sum of these molecular weights, and dividing by n, and the weight average molecular weight (Mw) indicates the molecular weight distribution of the polymer composition. All molecular weight averages may be expressed in grams per mole (g / mol). Also, the weight average molecular weight and the number average molecular weight may each mean a polystyrene-equivalent molecular weight analyzed by gel permeation chromatography (GPC).

[0119] According to one embodiment of the present invention, when the conjugated diene-based polymer satisfies the conditions of weight average molecular weight (Mw) and number average molecular weight as well as the molecular weight distribution, when applied to a rubber composition, the polymer has excellent tensile properties, viscoelasticity and processability with respect to the rubber composition, and has an excellent balance between these physical properties.

[0120] According to one embodiment of the present invention, the conjugated diene polymer may have a cis-1,4 bond content of 97.0 wt% or more, 97.5 wt% or more, 97.6 wt% or more, 97.9 wt% or more, 98.0 wt% or more, or 98.1 wt% or more, or may be 100.0 wt% or less, 99.5 wt% or less, or 99.0 wt% or less.

[0121] According to one embodiment of the present invention, the conjugated diene-based polymer may have a Mooney viscosity (ML1+4, @100°C) of 30 or more, 35 or more, 40 or more, 41 or more, 43 or more, or 44 or more, and may be 70 or less, 60 or less, 50 or less, 49 or less, or 45 or less.

[0122] Rubber composition The present invention provides a rubber composition.

[0123] According to an embodiment of the present invention, the rubber composition may include the conjugated diene polymer. As a specific example, the rubber composition may include the conjugated diene polymer in an amount of 0.1% by weight or more, 10% by weight or more, or 20% by weight or more, or may include the conjugated diene polymer in an amount of 100% by weight or less, 95% by weight or less, or 90% by weight or less. Within this range, a molded product, such as a tire, manufactured using the rubber composition may have sufficient abrasion resistance and crack resistance.

[0124] According to an embodiment of the present invention, the rubber composition may further include other rubber components, if necessary, in addition to the conjugated diene polymer. Here, the rubber components may be included in an amount of 90% by weight or less based on the total weight of the rubber composition. Specifically, the rubber components may be included in an amount of 1 to 900 parts by weight based on 100 parts by weight of the conjugated diene copolymer.

[0125] According to one embodiment of the present invention, the rubber component may be a natural rubber or a synthetic rubber. For example, the rubber component may be a natural rubber (NR) containing cis-1,4-polyisoprene; modified natural rubber such as epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber, which are obtained by modifying or refining the general natural rubber; styrene-butadiene copolymer (SBR), polybutadiene (BR), polyisoprene (IR), butyl rubber (IIR), ethylene-propylene copolymer, polyisobutylene-co-yne, etc. The rubber may be synthetic rubber such as isoprene, neoprene, poly(ethylene-co-propylene), poly(styrene-co-butadiene), poly(styrene-co-isoprene), poly(styrene-co-isoprene-co-butadiene), poly(isoprene-co-butadiene), poly(ethylene-co-propylene-codiene), polysulfide rubber, acrylic rubber, urethane rubber, silicone rubber, epichlorohydrin rubber, halogenated butyl rubber, etc., and any one or a mixture of two or more of these may be used.

[0126] According to an embodiment of the present invention, the rubber composition may include 20 parts by weight or more and 90 parts by weight or less of a filler based on 100 parts by weight of the conjugated diene-based polymer. The filler may be a silica-based filler, a carbon black-based filler, or a combination thereof. As a specific example, the filler may be a carbon black-based filler.

[0127] According to one embodiment of the present invention, the carbon black-based filler has a nitrogen adsorption specific surface area (NSA, measured in accordance with JIS K 6217-2:2001) of 20 m 2 / g~250m 2 / g, within this range, the rubber composition has excellent processability and the filler can sufficiently ensure reinforcing performance. The carbon black filler may have a dibutyl phthalate oil absorption (DBP) of 80 cc / 100 g to 200 cc / 100 g, within this range, the rubber composition has excellent processability and the filler can sufficiently ensure reinforcing performance.

[0128] According to one embodiment of the present invention, the silica-based filler may be wet silica (hydrated silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, colloidal silica, or the like. As a specific example, the silica-based filler may be wet silica, which has the most significant effect of improving fracture properties and wet grip. In addition, the silica-based filler may be a filler having a nitrogen surface area per gram (N2SA) of 120 m 2 / g~180m 2 / g, and the CTAB (cetyl trimethyl ammonium bromide) adsorption specific surface area is 100m 2 / g~200m 2 / g, and within this range, the rubber composition has excellent processability and the reinforcing performance of the filler can be sufficiently ensured.

[0129] According to an embodiment of the present invention, when a silica-based filler is used as the filler, a silane coupling agent may be used in combination to improve reinforcement and low heat generation. The silane coupling agent may be bis(3-triethoxysilylpropyl)tetrasulfide, bis(3-triethoxysilylpropyl)trisulfide, bis(3-triethoxysilylpropyl)disulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(3-trimethoxysilylpropyl)tetrasulfide, bis(2-trimethoxysilylethyl)tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-triethoxy ... -dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropyl benzothiazolyl tetrasulfide, 3-triethoxysilylpropyl benzolyl tetrasulfide, 3-triethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis(3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyl dimethoxymethyl silane, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyl tetrasulfide or dimethoxymethylsilylpropyl benzothiazolyl tetrasulfide may be used. As a specific example, the silane coupling agent may be bis(3-triethoxysilylpropyl) polysulfide or 3-trimethoxysilylpropyl benzothiazyl tetrasulfide in consideration of the effect of improving reinforcing properties.

[0130] According to one embodiment of the present invention, the rubber composition may be sulfur crosslinkable, and thus may further include a vulcanizing agent. The vulcanizing agent may specifically be sulfur powder, and may be included in an amount of 0.1 to 10 parts by weight per 100 parts by weight of the rubber component. Within this range, the necessary elastic modulus and strength of the vulcanized rubber composition can be ensured, and fuel economy can be ensured.

[0131] According to an embodiment of the present invention, the rubber composition may further include various additives commonly used in the rubber industry, such as a vulcanization accelerator, a process oil, a plasticizer, an antioxidant, a scorch inhibitor, zinc white, stearic acid, a thermosetting resin, or a thermoplastic resin, in addition to the above-mentioned components.

[0132] According to an embodiment of the present invention, the vulcanization accelerator is not particularly limited, and specifically, a thiazole-based compound such as M (2-mercaptobenzothiazole), DM (dibenzothiazyl disulfide), CZ (N-cyclohexyl-2-benzothiazyl sulfenamide), or a guanidine-based compound such as DPG (diphenyl guanidine) may be used. The vulcanization accelerator may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the rubber component.

[0133] According to one embodiment of the present invention, the process oil acts as a softener in the rubber composition, and may be, for example, a paraffinic, naphthenic, or aromatic compound, and, for example, in consideration of tensile strength and abrasion resistance, aromatic process oils may be used, and in consideration of hysteresis loss and low temperature properties, naphthenic or paraffinic process oils may be used. The process oil may be contained in an amount of 100 parts by weight or less per 100 parts by weight of the rubber component, and within this range, the tensile strength and low heat generation property (fuel economy) of the vulcanized rubber may be prevented from decreasing.

[0134] According to an embodiment of the present invention, the antioxidant may be N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, or a high temperature condensate of diphenylamine and acetone, etc. The antioxidant may be used in an amount of 0.1 to 6 parts by weight based on 100 parts by weight of the rubber component.

[0135] According to one embodiment of the present invention, the rubber composition can be obtained by kneading the compounding recipe using a kneading machine such as a Banbury mixer, a roll, or an internal mixer. After molding, a vulcanization process can be performed to obtain a rubber composition that has low heat generation and excellent abrasion resistance.

[0136] According to an embodiment of the present invention, the rubber composition can be used to manufacture various tire components such as tire tread, undertread, sidewall, carcass coating rubber, belt coating rubber, bead filler, shaper, or bead coating rubber, as well as various industrial rubber products such as anti-vibration rubber, belt conveyor, hose, etc. As a specific example, a molded product manufactured using the rubber composition can include a tire or a tire tread.

[0137] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to exemplary embodiments thereof, so that those skilled in the art can easily practice the present invention. However, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[0138] Working Example [Example 1] Four pressure-resistant reactors with a volume of 300 ml and equipped with a jacket and an agitator were connected in series and used as a continuous catalyst production reactor. Here, the third and fourth reactors were connected using piping equipped with a line mixer. Each reactor was maintained in a nitrogen atmosphere. A neodymium versatate solution diluted in n-hexane was continuously injected into the first reactor, and at the same time, 1,3-butadiene diluted in n-hexane was continuously injected, and a triethylaluminum solution diluted in n-hexane was continuously injected in a content of 10 moles of triethylaluminum per mole of neodymium. The temperature of the first reactor was operated at a temperature of 0°C, and after 10 minutes of continuous injection, the mixture mixed in the first reactor was transferred to the second reactor, and a diisobutylaluminum hydride solution diluted in n-hexane was continuously injected into the second reactor in a content of 15 moles of diisobutylaluminum hydride per mole of neodymium. The second reactor was operated at a temperature of 10°C, and after 20 minutes of continuous injection, the reactants in the second reactor were transferred to the third reactor. The third reactor was operated at a temperature of 10°C, and after 10 minutes of continuous injection, the reactants in the third reactor were transferred to the fourth reactor. A diethylaluminum chloride solution diluted with n-hexane was continuously injected into the fourth reactor at a content of 3 moles of diethylaluminum chloride per mole of neodymium. The third reactor was operated at a temperature of -5°C, and after 30 minutes of continuous injection, the catalyst composition prepared was taken out in a pressure-resistant container prepared in a nitrogen atmosphere and stored at a temperature below 0°C.

[0139] [Example 2] Four pressure-resistant reactors with a volume of 300 ml and equipped with a jacket and an agitator were connected in series and used as a continuous catalyst production reactor. Here, the third and fourth reactors were connected using piping equipped with a line mixer. Each reactor was maintained in a nitrogen atmosphere. A neodymium versatate solution diluted in n-hexane was continuously injected into the first reactor, and at the same time, 1,3-butadiene diluted in n-hexane was continuously injected, and a triethylaluminum solution diluted in n-hexane was continuously injected in a content of 10 moles of triethylaluminum per mole of neodymium. The temperature of the first reactor was operated at a temperature of 0°C, and after 10 minutes of continuous injection, the mixture mixed in the first reactor was transferred to the second reactor, and a diisobutylaluminum hydride solution diluted in n-hexane was continuously injected into the second reactor in a content of 15 moles of diisobutylaluminum hydride per mole of neodymium. The second reactor was operated at a temperature of 10°C, and after 15 minutes of continuous injection, the reactants in the second reactor were transferred to the third reactor. The third reactor was operated at a temperature of 10°C, and after 15 minutes of continuous injection, the reactants in the third reactor were transferred to the fourth reactor. A diethylaluminum chloride solution diluted with n-hexane was continuously injected into the fourth reactor at a content of 3 moles of diethylaluminum chloride per mole of neodymium. The third reactor was operated at a temperature of -5°C, and after 30 minutes of continuous injection, the catalyst composition prepared was taken out in a pressure-resistant container prepared in a nitrogen atmosphere and stored at a temperature below 0°C.

[0140] [Example 3] Four pressure-resistant reactors with a volume of 300 ml and equipped with a jacket and an agitator were connected in series and used as a continuous catalyst production reactor. Here, the third and fourth reactors were connected using piping equipped with a line mixer. Each reactor was maintained in a nitrogen atmosphere. A neodymium versatate solution diluted in n-hexane was continuously injected into the first reactor, and at the same time, 1,3-butadiene diluted in n-hexane was continuously injected, and a triethylaluminum solution diluted in n-hexane was continuously injected in a content of 10 moles of triethylaluminum per mole of neodymium. The temperature of the first reactor was operated at a temperature of 0°C, and after 10 minutes of continuous injection, the mixture mixed in the first reactor was transferred to the second reactor, and a diisobutylaluminum hydride solution diluted in n-hexane was continuously injected into the second reactor in a content of 15 moles of diisobutylaluminum hydride per mole of neodymium. The second reactor was operated at a temperature of 10°C, and after 10 minutes of continuous injection, the reactants in the second reactor were transferred to the third reactor. The third reactor was operated at a temperature of 10°C, and after 10 minutes of continuous injection, the reactants in the third reactor were retained in a pipe equipped with a line mixer at a temperature of 10°C for 10 minutes and then transferred to the fourth reactor. A diethylaluminum chloride solution diluted with n-hexane was continuously injected into the fourth reactor at a content of 3 moles of diethylaluminum chloride per mole of neodymium. The third reactor was operated at a temperature of -5°C, and after 30 minutes of continuous injection, the catalyst composition prepared was separated into a pressure-resistant container prepared in a nitrogen atmosphere and stored at a temperature below 0°C.

[0141] [Example 4] Four pressure-resistant reactors with a volume of 300 ml and equipped with a jacket and an agitator were connected in series and used as a continuous catalyst production reactor. Here, the third and fourth reactors were connected using piping equipped with a line mixer. Each reactor was maintained in a nitrogen atmosphere. A neodymium versatate solution diluted in n-hexane was continuously injected into the first reactor, and at the same time, 1,3-butadiene diluted in n-hexane was continuously injected, and a triethylaluminum solution diluted in n-hexane was continuously injected in a content of 10 moles of triethylaluminum per mole of neodymium. The temperature of the first reactor was operated at a temperature of 0°C, and after 10 minutes of continuous injection, the mixture mixed in the first reactor was transferred to the second reactor, and a diisobutylaluminum hydride solution diluted in n-hexane was continuously injected into the second reactor in a content of 15 moles of diisobutylaluminum hydride per mole of neodymium. The second reactor was operated at 0°C, and after 30 minutes of continuous injection, the reactants in the second reactor were transferred to the third reactor. The third reactor was operated at 10°C, and after 15 minutes of continuous injection, the reactants in the third reactor were retained in a pipe equipped with a line mixer at 10°C for 10 minutes and then transferred to the fourth reactor. A diethylaluminum chloride solution diluted with n-hexane was continuously injected into the fourth reactor at a content of 3 moles of diethylaluminum chloride per mole of neodymium. The third reactor was operated at -5°C, and after 30 minutes of continuous injection, the catalyst composition prepared was separated into a pressure-resistant container prepared in a nitrogen atmosphere and stored at a temperature below 0°C.

[0142] [Comparative Example 1] Two pressure-resistant reactors with a volume of 300 ml and equipped with a jacket and an agitator were connected in series and used as a continuous catalyst production reactor. Each reactor was maintained in a nitrogen atmosphere. A neodymium versatate solution diluted in n-hexane was continuously injected into the first reactor, and at the same time, 1,3-butadiene diluted in n-hexane was continuously injected, and a diisobutylaluminum hydride solution diluted in n-hexane was continuously injected at a content of 15 moles of diisobutylaluminum hydride per mole of neodymium. The temperature of the first reactor was operated at 0°C, and after 30 minutes of continuous injection, the reactants of the first reactor were transferred to the second reactor, and a diethylaluminum chloride solution diluted in n-hexane was continuously injected into the second reactor at a content of 3 moles of diethylaluminum chloride per mole of neodymium. The second reactor was operated at a temperature of -5°C, and after 30 minutes of continuous injection, the prepared catalyst composition was dispensed into a pressure-resistant vessel prepared in a nitrogen atmosphere and stored at a temperature below 0°C.

[0143] [Comparative Example 2] 1,3-butadiene diluted with n-hexane was added to the reactor, followed by neodymium versatate (Solvay). Then, diisobutylaluminum hydride was added to the reactor at a content of 15 moles of diisobutylaluminum hydride per mole of neodymium at a temperature of 0°C and stirred for 30 minutes. Then, diethylaluminum chloride was added to the reactor at a content of 3 moles of diethylaluminum chloride per mole of neodymium at a temperature of -5°C and stirred for 30 minutes to prepare a catalyst composition.

[0144] [Comparative Example 3] 1,3-butadiene diluted with n-hexane was added to the reactor, followed by neodymium versatate (Solvay). Then, triisobutylaluminum was added to the reactor at a content of 30 moles per mole of neodymium at a temperature of 0°C and stirred for 30 minutes. Then, diethylaluminum chloride was added to the reactor at a content of 3 moles per mole of neodymium at a temperature of -5°C and stirred for 30 minutes to prepare a catalyst composition.

[0145] [Experimental Example] <Experimental Example 1: Production of conjugated diene polymer and evaluation of catalyst composition activity> 500g of 1,3-butadiene and 4.2kg of n-hexane were put into a 20L autoclave reactor, and the internal temperature of the reactor was raised to 70°C. When the catalyst composition prepared in Examples 1 to 4 was used, 0.01g of diisobutylaluminum hydride was added as a molecular weight regulator, and when the catalyst composition prepared in Comparative Examples 1 to 3 was used, 0.25g of diisobutylaluminum hydride was added as a molecular weight regulator, and the catalyst composition prepared in Examples 1 to 4 and Comparative Examples 1 to 3 was added, and polymerization was carried out. When the polymerization conversion rate reached 98% or more, an n-hexane solution containing 1.0g of polymerization terminator and a solution in which an antioxidant Irganox 1520 (BAS) was dissolved in n-hexane at 30% by weight were added to terminate the reaction. The obtained polymer was put into hot water heated with steam, stirred to remove the solvent, and then roll-dried to remove the remaining solvent and water, to produce a butadiene polymer.

[0146] During the preparation of the butadiene polymer, a portion of the polymerization solution was taken after 25 minutes of reaction time had elapsed since the start of polymerization, and the TSC (total solid content, %) was measured, and the polymerization conversion was calculated according to the following mathematical formula 1. The polymerization conversion after 25 minutes of reaction time was measured for each catalyst composition of Examples 1 to 4 and Comparative Examples 1 to 3 to evaluate the activity of the catalyst composition, which is shown in Table 1 below. The measured value of Comparative Example 2 was used as a reference value, and the activity of the catalyst composition of each Example and Comparative Example was indexed using the following mathematical formula 2.

[0147] [Mathematical formula 1] Polymerization conversion rate (%) = TSC of sample (%) / 1,3-butadiene concentration (wt%)

[0148] [Mathematical formula 2] Activity Index = (measured value / reference value) x 100

[0149] [Table 1]

[0150] As shown in Table 1, it was confirmed that the catalyst compositions prepared in Examples 1 to 4 exhibited significantly higher activity than those prepared in Comparative Examples 1 to 3.

[0151] On the other hand, in the case of Comparative Example 1, in which the pretreatment step using triethylaluminum was not carried out on the lanthanum rare earth element compound according to the present invention, it was confirmed that the activity of the catalyst composition was decreased compared to Examples 1 to 4, in which the same alkylating agent and halogen compound were used.

[0152] In addition, in Comparative Example 2, in which the pretreatment step using triethylaluminum was not carried out on the lanthanum rare earth compound according to the present invention and the catalyst composition was prepared using a batch reactor, the activity of the catalyst composition was also confirmed to be reduced compared to Examples 1 to 4, in which the same alkylating agent and halogen compound were used.

[0153] In addition, in the case of Comparative Example 3 in which the catalytic composition was prepared using a batch reactor without carrying out the pretreatment step using triethylaluminum on the lanthanum rare earth compound according to the present invention, even when the alkylating agent was changed to triisobutylaluminum and used in an excessive amount, the alkylation reaction did not proceed sufficiently, and it was confirmed that the activity of the catalytic composition was reduced compared to Examples 1 to 4, especially compared to Example 4 in which the same alkylating agent and halogen compound were used.

[0154] <Experimental Example 2: Evaluation of physical properties of conjugated diene polymer> The conjugated diene polymers produced in Experimental Example 1 using the catalyst compositions of Examples 1 to 4 and Comparative Examples 1 to 3 were measured for Mooney viscosity, molecular weight distribution and cis-1,4 bond content as described below, and the results are shown in Table 2 below.

[0155] *Mooney viscosity (ML1+4, @100℃): For each polymer, Mooney viscosity was measured at 100℃ using a Monsanto MV2000E Large Rotor at rotor speed 2±0.02 rpm. The sample used was left at room temperature (23±3℃) for 30 minutes or more, and then 27±3g was taken and filled into the die cavity. The platen was operated to apply torque and measure the Mooney viscosity.

[0156] * Weight average molecular weight (Mw), number average molecular weight (Mn) and molecular weight distribution (MWD): Each polymer was dissolved in tetrahydrofuran (THF) for 30 minutes at 40°C, and then loaded onto gel permeation chromatography (GPC) and run. Two PLgel Olexis columns and one PLgel mixed-C column from Polymer Laboratories were used in combination. All newly replaced columns were mixed bed type columns, and polystyrene was used as the GPC standard material.

[0157] *Cis-1,4 bond content: The cis-1,4 bond content of the conjugated diene portion was measured by Fourier transform infrared spectroscopy (FT-IR). Specifically, carbon disulfide in the same cell was used as a blank, and the FT-IR transmittance spectrum of a carbon disulfide solution of a conjugated diene polymer prepared at a concentration of 5 mg / mL was measured. -1 The maximum peak value a (baseline) near 967 cm indicates a trans-1,4 bond. -1 The minimum peak value b near 911 cm indicates a vinyl bond. -1 The minimum peak value c near 736 cm indicates a cis-1,4 bond. -1 The respective contents were calculated using the minimum peak value d in the vicinity.

[0158] [Table 2]

[0159] As shown in Table 2, it was confirmed that the conjugated diene-based polymers prepared using the catalyst compositions prepared in Examples 1 to 4 exhibited appropriate levels of Mooney viscosity and molecular weight distribution, and also had a high level of cis-1,4 bond content.

[0160] Meanwhile, it was confirmed that the conjugated diene-based polymers prepared using the catalyst compositions prepared in Comparative Examples 1 to 3 had a lower cis-1,4 bond content and a wider molecular weight distribution than those in Examples 1 to 4.

[0161] <Experimental Example 3: Evaluation of rubber composition properties> Using the catalyst compositions of Examples 1 to 4 and Comparative Examples 1 to 3 and the conjugated diene-based polymer produced in Experimental Example 1, rubber compositions and rubber test specimens were produced. The Mooney viscosity, abrasion resistance, tensile properties and viscoelastic properties of the rubber compositions were measured by the following methods, and are shown in Table 3 below.

[0162] <Production of Rubber Composition and Rubber Test Pieces> Using the catalyst compositions of Examples 1 to 4 and Comparative Examples 1 to 3, 100 parts by weight of the conjugated diene polymer produced in Experimental Example 1 was mixed with 70 parts by weight of carbon black, 22.5 parts by weight of process oil (TDAE oil), 2 parts by weight of antioxidant (TMDQ), 3 parts by weight of zinc oxide (ZnO), and 2 parts by weight of stearic acid to produce the conjugated diene polymer.

[0163] Next, 2 parts by weight of sulfur, 2 parts by weight of a vulcanization accelerator (CZ), and 0.5 parts by weight of a vulcanization accelerator (DPG) were added to each of the rubber compositions, and the mixture was weakly mixed at 50 rpm at 50°C for 1 minute and 30 seconds. A sheet-shaped vulcanization mixture was then produced using a roll at 50°C, and the vulcanization mixture was vulcanized at 160°C for 25 minutes to produce rubber test pieces.

[0164] *Tensile properties: After vulcanizing each rubber composition at 150°C for 90 minutes, the modulus of the vulcanized material at 300% elongation (M-300%, kg f / cm) was measured according to ASTM D412. 2 The measured value of Comparative Example 2 was used as a reference value, and the 300% modulus of each of the Examples and Comparative Examples was indexed using the following mathematical formula 3.

[0165] [Mathematical formula 3] M-300%Index = (measured value / reference value) x 100

[0166] * Viscoelastic properties: Using a DMTS 500N manufactured by Gabo, Germany, the viscoelastic coefficient (Tan δ) was measured at a frequency of 10 Hz, prestrain 3%, and dynamic strain 3% at temperatures from -60°C to 60°C. Here, the Tan δ value at 0°C indicates the rolling resistance, and the Tan δ value at 60°C indicates the rolling resistance characteristics (fuel economy). The measured value of Comparative Example 2 was used as the reference value, and the viscoelastic properties of each Example and Comparative Example were indexed using the following mathematical formula 4.

[0167] [Mathematical formula 4] Tan δ 60℃Index = (reference value / measured value) × 100

[0168] *Abrasion resistance: A DIN abrasion test was performed on each of the prepared rubber test pieces according to ASTM D5963, and the results were expressed as a DIN wt loss index (loss volume index: ARIA (Abrasion resistance index, Method A)). The measured value of Comparative Example 2 was used as a reference value, and the abrasion resistance of each of the Examples and Comparative Examples was indexed using the following Equation 5.

[0169] [Mathematical formula 5] Wear Index = (reference value / measured value) x 100

[0170] [Table 3]

[0171] As shown in Table 3, the rubber compositions prepared including the conjugated diene polymers prepared using the catalyst compositions prepared in Examples 1 to 4 were found to have improved tensile properties, viscoelastic properties, and abrasion resistance compared to the rubber compositions prepared including the conjugated diene polymers prepared using the catalyst compositions prepared in Comparative Examples 1 to 3.

[0172] Meanwhile, it was confirmed that the rubber composition prepared including the conjugated diene polymer prepared using the catalyst composition prepared in Comparative Example 1 had lower tensile properties, viscoelastic properties, and abrasion resistance than the rubber composition prepared including the conjugated diene polymer prepared using the catalyst composition prepared in Comparative Example 2.

[0173] This result is attributable to the improved catalytic activity achieved by pretreating hydrogen-bonded lanthanum rare earth compounds and / or oligomeric forms of lanthanum rare earth compounds, which cause a decrease in catalytic activity, prior to the alkylation reaction during the preparation of the catalyst composition for producing a conjugated diene polymer.

[0174] From these results, it was confirmed that the catalyst composition prepared by the method for preparing the catalyst composition of the present invention has excellent catalytic activity because it is prepared by pretreating hydrogen-bonded lanthanum rare earth compounds and / or oligomer forms of lanthanum rare earth compounds, which cause a decrease in catalytic activity, before the alkylation reaction.

[0175] In addition, it has been confirmed that the conjugated diene polymer produced by the method for producing a conjugated diene polymer of the present invention has a low content of lanthanum-based rare earth elements remaining in the conjugated diene polymer due to its high catalytic activity, a high content and linearity of cis bonds, and a narrow molecular weight distribution, and when applied to a rubber composition, it exhibits excellent wear resistance and low fuel consumption.

Claims

1. A pretreatment step (S10) of carrying out a pretreatment reaction of hydrogen bonding, oligomer formation, or a combination thereof with respect to a lanthanum rare earth compound; an alkylation reaction step (S20) of mixing and reacting the lanthanum rare earth compound pretreated in the hydrogen bond, oligomer form, or a combination thereof in the step (S10) with an alkylating agent; and a halogenation reaction step (S30) of mixing and reacting the lanthanum rare earth compound alkylated in the step (S20) with a halogen compound, The method for preparing a catalyst composition, wherein the step (S20) is continuously performed in a plurality of reactors connected in series.

2. 2. The method for producing a catalyst composition according to claim 1, wherein the step (S10) is carried out by mixing and reacting the lanthanum rare earth compound with one or more trialkylaluminums selected from the group consisting of trimethylaluminum and triethylaluminum.

3. The method for producing a catalyst composition according to claim 2, wherein the step (S10) is carried out before the lanthanum rare earth compound is alkylated with trialkylaluminum.

4. 2. The method for producing a catalyst composition according to claim 1, wherein the lanthanum rare earth compound is a neodymium compound represented by the following chemical formula 1: 【Chemistry 5】 In the above Chemical Formula 1, R 1 ~R 3 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 1 ~R 3 But it's not all hydrogen.

5. The lanthanum rare earth element compound is Nd(2-ethylhexanoate). 3 , Nd(2,2-dimethyldecanoate) 3 , Nd(2,2-diethyldecanoate) 3 , Nd(2,2-dipropyl decanoate) 3 , Nd(2,2-dibutyldecanoate) 3 , Nd(2,2-dihexyldecanoate) 3 , Nd(2,2-dioctyldecanoate) 3 , Nd(2-ethyl-2-propyl decanoate) 3 , Nd(2-ethyl-2-butyldecanoate) 3 , Nd(2-ethyl-2-hexyldecanoate) 3 , Nd(2-propyl-2-butyldecanoate) 3 , Nd(2-propyl-2-hexyldecanoate) 3 , Nd(2-propyl-2-isopropyl decanoate) 3 , Nd(2-butyl-2-hexyldecanoate) 3 , Nd(2-hexyl-2-octyldecanoate) 3 , Nd(2,2-diethyl octanoate) 3 , Nd(2,2-dipropyl octanoate) 3 , Nd(2,2-dibutyl octanoate) 3 , Nd(2,2-dihexyl octanoate) 3 , Nd(2-ethyl-2-propyl octanoate) 3 , Nd(2-ethyl-2-hexyl octanoate) 3 , Nd(2,2-diethylnonanoate) 3 , Nd(2,2-dipropyl nonanoate) 3 , Nd(2,2-dibutylnonanoate) 3 , Nd(2,2-dihexylnonanoate) 3 , Nd(2-ethyl-2-propyl nonanoate) 3 and Nd(2-ethyl-2-hexylnonanoate) 3 The method for producing a catalyst composition according to claim 1, wherein the catalyst is one or more selected from the group consisting of:

6. The method for preparing a catalyst composition according to claim 1, wherein the alkylating agent is an alkylaluminum compound represented by the following formula 2: [Chemical formula 2] AlR 4 R 5 R 6 In the above Chemical Formula 2, R 4 ~R 6 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R 4 ~R 6 is not all hydrogen, R 4 ~R 6 When all of the groups are alkyl groups, the alkyl groups each have 3 to 12 carbon atoms.

7. The method for preparing a catalyst composition according to claim 1, wherein the alkylating agent is a dialkylaluminum hydride.

8. 2. The method for producing a catalyst composition according to claim 1, wherein the pretreatment reaction in step (S10), the alkylation reaction in step (S20), or the pretreatment reaction in step (S10) and the alkylation reaction in step (S20) are carried out using a conjugated diene monomer.

9. The method for producing a catalyst composition according to claim 1, wherein the halogen compound is at least one selected from the group consisting of alkylaluminum halides represented by the following formula 3 and alkylaluminum sesquihalides represented by the following formula 4: [Chemical formula 3] AlR 7 R 8 R 9 In the above Chemical Formula 3, R 7 ~R 9 are each independently a halogen group or an alkyl group having 1 to 12 carbon atoms, and R 7 ~R 9 are not all halogen groups, 【Chemistry 6】 In the above Chemical Formula 4, R 10 ~R 12 are each independently an alkyl group having 1 to 12 carbon atoms, X 1 ~X 3 are each independently a halogen group.

10. The method for producing a catalyst composition according to claim 1, wherein the halogen compound is at least one selected from the group consisting of dialkylaluminum halides and alkylaluminum sesquihalides.

11. The method for producing a catalyst composition according to claim 1, wherein the steps (S10), (S20) and (S30) are each carried out in separate reactors connected in series.

12. The method for producing a catalyst composition according to claim 1, wherein the steps (S10), (S20) and (S30) are carried out consecutively.

13. The method for producing a catalyst composition according to claim 1, wherein the alkylating agent is divided and fed to the plurality of reactors connected in series.

14. A method for producing a conjugated diene polymer, comprising the step (S100) of polymerizing a conjugated diene monomer in a hydrocarbon solvent in the presence of a catalyst composition produced by the method for producing a catalyst composition according to claim 1 to produce an activated polymer.

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