Modified conjugated diene-based polymer and method for preparing same

Abstract

The present invention relates to a modified conjugated diene-based polymer comprising a modifying moiety derived from a modifying agent which can be used for modifying a conjugated diene-based polymer, has excellent affinity with a filler, and thus can improve the blending performance of the conjugated diene-based polymer, and a method for preparing the same.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority based on Korean Patent Application No. 10-2022-0167041 filed on December 2, 2022, the entire contents of which are hereby incorporated by reference. Technical Field

[0003] The present invention relates to a modified conjugated diene polymer comprising a modified portion derived from a modifier and a method for preparing the modified conjugated diene polymer. The modified portion can be used to modify the conjugated diene polymer, has excellent affinity with a filler and improves the compounding performance of the conjugated diene polymer. Background Art

[0004] According to recent demands for automobiles with low fuel consumption ratio, conjugated diene-based polymers having regulation stability represented by wet skid resistance and low rolling resistance, and excellent wear resistance and tensile properties are required as rubber materials for tires.

[0005] In order to reduce the rolling resistance of the tire, there is a method of reducing the hysteresis loss of the vulcanized rubber, and rebound resilience, tan δ, Goodrich heat, etc. at 50° C. to 80° C. are used as evaluation indicators of the vulcanized rubber. That is, it is desirable to use a rubber material having high rebound resilience at the above temperature or a low tan δ value or Goodrich heat.

[0006] Natural rubber, polyisoprene rubber or polybutadiene rubber are known as rubber materials with low hysteresis loss, but these rubbers have the limitation of low wet skid resistance. Therefore, conjugated diene polymers or copolymers such as styrene-butadiene rubber (hereinafter referred to as "SBR") and butadiene rubber (hereinafter referred to as "BR") have been prepared recently by emulsion polymerization or solution polymerization to be used as tire rubber. Among these polymerization methods, the greatest advantage of solution polymerization compared with emulsion polymerization is that the vinyl structure content and styrene content of the physical properties of the specified rubber can be arbitrarily adjusted, and its molecular weight and physical properties can be controlled by coupling or modification. Therefore, SBR prepared by solution polymerization is widely used as a rubber material for tires, because it is easy to change the structure of the SBR or BR finally prepared, and the movement of the chain end can be reduced, and the coupling force with fillers such as silica and carbon black can be increased by coupling or modification of the chain end.

[0007] If solution polymerized SBR is used as a rubber material for tires, since the glass transition temperature of the rubber is increased by increasing the vinyl content in SBR, physical properties such as driving resistance and braking force required for tires can be controlled, and fuel consumption can be reduced by appropriately adjusting the glass transition temperature. Solution polymerized SBR is prepared by using an anionic polymerization initiator and is used by coupling or modifying the chain ends of the polymers thus formed using various modifiers. For example, U.S. Patent No. 4397994 discloses a method for coupling the active anions of the chain ends of polymers obtained by polymerizing styrene-butadiene using a coupling agent such as a tin compound, using an alkyl lithium (which is a monofunctional initiator) in a non-polar solvent.

[0008] Meanwhile, carbon black, silica, etc. are used as reinforcing fillers for tire treads. If silica is used as a reinforcing filler, there are advantages of improving low hysteresis loss and wet skid resistance. However, compared with carbon black having a hydrophobic surface, silica having a hydrophilic surface has the defects of low affinity and poor dispersibility, and in order to improve dispersibility or provide coupling between silica and rubber, a separate silane coupling agent is required. Therefore, a method of introducing a functional group having affinity or reactivity with silica at the end of a rubber molecule is adopted, but the effect is insufficient.

[0009] [Prior art literature]

[0010] [Patent Document]

[0011] (Patent Document 1) US 4397994A Summary of the invention

[0012] Technical issues

[0013] An object of the present invention is to provide a modified conjugated diene-based polymer, which is modified by a modifier represented by Formula 1 and has a high modification ratio and excellent affinity with a filler, and a method for preparing the same.

[0014] Technical Solution

[0015] In order to solve the above problems, the present invention provides a modified conjugated diene polymer and a preparation method thereof.

[0016] (1) The present invention provides a modified conjugated diene polymer comprising a repeating unit derived from a conjugated diene monomer and a modified portion derived from a modifier represented by Formula 1.

[0017] [Formula 1]

[0018]

[0019] In formula 1,

[0020] A is an arylene group of 6 to 30 carbon atoms, or a heteroarylene group of 2 to 30 carbon atoms containing 1 to 3 N atoms,

[0021] L1 and L2 are each independently an alkylene group of 1 to 20 carbon atoms,

[0022] L3 and L4 are each independently an alkylene group of 1 to 20 carbon atoms, and

[0023] R1 to R6 are each independently an alkyl group of 1 to 10 carbon atoms or an alkoxy group of 1 to 20 carbon atoms, wherein at least one of R1 to R3 is an alkoxy group of 1 to 20 carbon atoms, and at least one of R4 to R6 is an alkoxy group of 1 to 20 carbon atoms.

[0024] (2) The present invention provides a modified conjugated diene-based polymer according to (1), wherein, in Formula 1, A is an arylene group having 6 to 20 carbon atoms, or a heteroarylene group having 3 to 20 carbon atoms containing 1 or 2 N atoms.

[0025] (3) The present invention provides a modified conjugated diene polymer according to (1) or (2), wherein, in Formula 1, L1 and L2 are each independently an alkylene group of 1 to 10 carbon atoms, wherein L1 and L2 are the same, and L3 and L4 are each independently an alkylene group of 1 to 10 carbon atoms, wherein L3 and L4 are the same.

[0026] (4) The present invention provides the modified conjugated diene-based polymer according to any one of (1) to (3), wherein, in Formula 1, R1 to R6 are each independently an alkoxy group having 1 to 10 carbon atoms.

[0027] (5) The present invention provides the modified conjugated diene-based polymer according to any one of (1) to (4), wherein the modifier represented by Formula 1 is selected from the compounds represented by Formula 1A and Formula 1B.

[0028] [Formula 1A]

[0029]

[0030] [Formula 1B]

[0031]

[0032] In Formula 1A and Formula 1B,

[0033] Definitions of L1 to L4 and R1 to R6 are the same as those in Formula 1.

[0034] (6) The present invention provides the modified conjugated diene-based polymer according to any one of (1) to (5), wherein the modifier represented by Formula 1 is selected from the compounds represented by Formula 1-1 to Formula 1-3.

[0035] [Formula 1-1]

[0036]

[0037] [Formula 1-2]

[0038]

[0039] [Formula 1-3]

[0040]

[0041] (7) The present invention provides the modified conjugated diene-based polymer according to any one of (1) to (6), which has a weight average molecular weight of 10,000 g / mol to 2,000,000 g / mol.

[0042] (8) The present invention provides the modified conjugated diene-based polymer according to any one of (1) to (7), which has a molecular weight distribution of 1.0 to 8.0.

[0043] (9) The present invention provides a method for preparing a modified conjugated diene polymer, comprising: (S1) a step of polymerizing a conjugated diene monomer or an aromatic vinyl monomer and a conjugated diene monomer in a hydrocarbon solvent containing an organic metal compound to prepare a living polymer coupled with an organic metal; and (S2) a step of reacting the living polymer with a modifier represented by the following formula 1.

[0044] [Formula 1]

[0045]

[0046] In formula 1,

[0047] A is an arylene group of 6 to 30 carbon atoms, or a heteroarylene group of 2 to 30 carbon atoms containing 1 to 3 N atoms,

[0048] L1 and L2 are each independently an alkylene group of 1 to 20 carbon atoms,

[0049] L3 and L4 are each independently an alkylene group of 1 to 20 carbon atoms, and

[0050] R1 to R6 are each independently an alkyl group of 1 to 10 carbon atoms or an alkoxy group of 1 to 20 carbon atoms, wherein at least one of R1 to R3 is an alkoxy group of 1 to 20 carbon atoms, and at least one of R4 to R6 is an alkoxy group of 1 to 20 carbon atoms.

[0051] (10) The present invention provides the method for preparing a modified conjugated diene-based polymer according to (9), wherein the amount of the organic metal compound used is 0.01 mmol to 10 mmol based on 100 g of the total monomer.

[0052] (11) The present invention provides a method for preparing a modified conjugated diene-based polymer according to (9) or (10), wherein the modifier represented by Formula 1 and the organic metal compound are used in a molar ratio of 1:0.1 to 1:5.0.

[0053] Beneficial effects

[0054] The modified conjugated diene-based polymer according to the present invention includes a modified portion derived from the modifier represented by Formula 1, and has the effects of significantly improved wear resistance and high affinity with fillers, and exhibits excellent processability and compounding properties. DETAILED DESCRIPTION

[0055] Hereinafter, the present invention will be described in more detail to help understanding of the present invention.

[0056] It should be understood that the words or terms used in the specification and claims of the present invention should not be interpreted as the meanings defined in commonly used dictionaries. It should also be understood that based on the principle that the inventor can appropriately define the meanings of words or terms to best explain the present invention, the words or terms should be interpreted as having a meaning consistent with the meaning of the technical idea of ​​the present invention.

[0057] Hereinafter, the present invention will be explained in detail.

[0058] Definition of terms

[0059] In the present invention, the term "substituted" may mean that the hydrogen of a functional group, an atomic radical or a compound is replaced by a specific substituent, and if the hydrogen of a functional group, an atomic radical or a compound is replaced by a specific substituent, then one or more (including two or more) substituents may be present depending on the number of hydrogen present in the functional group, the atomic radical or the compound, and if multiple substituents are present, the substituents may be the same or different.

[0060] In the present invention, the term "alkyl" may refer to a monovalent aliphatic saturated hydrocarbon, and may include straight chain alkyl groups such as methyl, ethyl, propyl and butyl and branched chain alkyl groups such as isopropyl, sec-butyl, tert-butyl and neopentyl.

[0061] In the present invention, the term "alkylene group" may refer to a divalent aliphatic saturated hydrocarbon such as methylene, ethylene, propylene and butylene.

[0062] In the present invention, the term "alkoxy group" may include all functional groups, atomic groups and compounds in which hydrogen at the terminal of an alkyl group is substituted with an oxygen atom, such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group.

[0063] In the present invention, the term "heteroalkyl group" may refer to an alkyl group in which carbon atoms (excluding terminal carbon atoms) in the alkyl group are substituted with one or more hetero atoms.

[0064] In the present invention, the term "cycloalkyl group" may refer to a cyclic saturated hydrocarbon.

[0065] In the present invention, the term "aryl group" may refer to an aromatic hydrocarbon, and may include a monocyclic aromatic hydrocarbon in which one ring is formed and a polycyclic aromatic hydrocarbon in which two or more rings are combined.

[0066] In the present invention, the term "heteroaryl" may include all aryl groups in which the carbon atoms in the aryl group are replaced by one or more heteroatoms.

[0067] In the present invention, the terms "derived unit" and "derived functional group" may refer to a component or structure derived from a certain material, or the material itself.

[0068] Modified conjugated diene polymers

[0069] The present invention provides a modified conjugated diene-based polymer comprising a modified portion derived from a modifier represented by Formula 1.

[0070] The modified conjugated diene-based polymer is characterized by including a repeating unit derived from a conjugated diene-based monomer and a modified portion derived from a modifier represented by Formula 1 below.

[0071] [Formula 1]

[0072]

[0073] In formula 1,

[0074] A is an arylene group of 6 to 30 carbon atoms, or a heteroarylene group of 2 to 30 carbon atoms containing 1 to 3 N atoms,

[0075] L1 and L2 are each independently an alkylene group of 1 to 20 carbon atoms,

[0076] L3 and L4 are each independently an alkylene group of 1 to 20 carbon atoms, and

[0077] R1 to R6 are each independently an alkyl group of 1 to 10 carbon atoms or an alkoxy group of 1 to 20 carbon atoms, wherein at least one of R1 to R3 is an alkoxy group of 1 to 20 carbon atoms, and at least one of R4 to R6 is an alkoxy group of 1 to 20 carbon atoms.

[0078] In one embodiment of the present invention, if one or both ends of a polymer or a polymer chain in a polymer forms a coupling bond through a derivative unit of a modifying agent, the modified moiety may be a coupling binding moiety.

[0079] In particular, in Formula 1, A may be an arylene group of 6 to 20 carbon atoms, or a heteroarylene group of 3 to 20 carbon atoms including 1 or 2 N atoms, or may be an arylene group of 6 to 10 carbon atoms, or a heteroarylene group of 3 to 20 carbon atoms including 1 or 2 N atoms. In particular, A may be an arylene group including phenylene, naphthyl, biphenylene, anthrylene, phenanthrenyl, fluorenyl, etc., or may be a pyrrolylene, pyrazolylene, pyridylene, pyrimidylene, triazinylene, carbazolylene, etc.

[0080] In particular, in Formula 1, L1 and L2 may each independently be an alkylene group of 1 to 10 carbon atoms, wherein L1 and L2 are the same, and L3 and L4 may each independently be an alkylene group of 1 to 10 carbon atoms, wherein L3 and L4 are the same. For example, L1 and L2 may be the same and may be an alkylene group of 1 to 10 carbon atoms, an alkylene group of 1 to 6 carbon atoms, a methylene group, an ethylene group, a propylene group, a butylene group, etc., and L3 and L4 may be the same and may be an alkylene group of 1 to 10 carbon atoms, an alkylene group of 1 to 6 carbon atoms, a methylene group, an ethylene group, a propylene group, a butylene group, etc. L1 and L2 may be a methylene group, and L3 and L4 may be a propylene group.

[0081] Particularly, in Formula 1, R1 to R6 may all be alkoxy groups of 1 to 10 carbon atoms, for example, R1 to R6 may each independently be an alkoxy group of 1 to 6 carbon atoms, an alkoxy group of 1 to 3 carbon atoms, a methoxy group, an ethoxy group, or the like.

[0082] In particular, the modifier represented by Formula 1 may be selected from compounds represented by Formula 1A and Formula 1B.

[0083] [Formula 1A]

[0084]

[0085] [Formula 1B]

[0086]

[0087] In Formula 1A and Formula 1B,

[0088] Definitions of L1 to L4 and R1 to R6 are the same as those in Formula 1.

[0089] In the modifier represented by Formula 1, the core ring structure thereof is an arylene group of 6 to 20 carbon atoms or a heteroarylene group of 5 to 20 carbon atoms including 1 to 3 N atoms, and the alkoxysilane functional groups at both ends of the modifier have an electron density that is easy to bond with the conjugated diene polymer. In addition, the modifier represented by Formula 1 forms a planar structure over the entire compound and can easily form a bond with the conjugated diene polymer without steric hindrance. In contrast, if the inner core ring has a cycloalkyl structure, the modifier may have a distorted structure, and contact and reaction with the conjugated diene polymer may proceed slowly.

[0090] In addition, if the N atom is included in the modifier, side reactions may occur easily, and a strong base material is needed to react steadily. However, since aminosilane is weak relative to a strong base material, the problem is that it is difficult to control the reaction environment, and the synthesis yield of the modifier is low. Therefore, in the present invention, if the kernel is a sub-heteroaryl, the number of N included therein is limited to 1 to 3 for effective preparation, so that it is easy to use in the modification reaction, and does not show such a problem.

[0091] Furthermore, the modifier represented by Formula 1 may have excellent solubility in a reaction solvent, and if a modified conjugated diene-based polymer is prepared using the modifier, a modified conjugated diene-based polymer showing a high modification rate may be prepared.

[0092] Furthermore, the modifier represented by Formula 1 of the present invention can be easily prepared without performing many steps.

[0093] The modifier represented by Formula 1 may be selected from compounds represented by Formula 1-1 to Formula 1-3.

[0094] [Formula 1-1]

[0095]

[0096] [Formula 1-2]

[0097]

[0098] [Formula 1-3]

[0099]

[0100] In the present invention, the modifier represented by Formula 1 may be prepared through a reaction step of a compound represented by Formula 2 with a compound represented by Formula 3 or Formula 4.

[0101] [Formula 2]

[0102]

[0103] [Formula 3]

[0104]

[0105] [Formula 4]

[0106]

[0107] In Formula 2, A1 and A2 may each independently be a halogen atom, in particular Cl.

[0108] In Formulae 2 to 4, the definition of each substituent is the same as defined above.

[0109] In this step, the compound represented by Formula 2 and the compound represented by Formula 3 or Formula 4 may be reacted in a molar ratio of 1:1.5 to 1:5.0, a molar ratio of 1:1.5 to 1:3.0, or a molar ratio of 1:1.5 to 1:2.5.

[0110] In this step, the reaction of the compound represented by Formula 2 with the compound represented by Formula 3 or Formula 4 may be performed at a temperature of 20 to 200° C., 30 to 180° C., or 40 to 150° C. for 1 to 72 hours.

[0111] In the present invention, the repeating unit derived from a conjugated diene monomer may refer to a repeating unit formed during the polymerization of the conjugated diene monomer, and the conjugated diene monomer may be, for example, one or more selected from 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-1,3-octadiene, isoprene, 2-phenyl-1,3-butadiene and 2-halogeno-1,3-butadiene (halogeno refers to a halogen atom).

[0112] Meanwhile, the modified conjugated diene-based copolymer may be a copolymer further including a repeating unit derived from an aromatic vinyl monomer and a repeating unit derived from a conjugated diene-based monomer.

[0113] The repeating unit derived from an aromatic vinyl monomer may refer to a repeating unit formed during the polymerization of an aromatic vinyl monomer, and the aromatic vinyl monomer may be, for example, one or more selected from styrene, α-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4-(p-methylphenyl)styrene and 1-vinyl-5-hexylnaphthalene.

[0114] If the modified conjugated diene polymer is a copolymer comprising a repeating unit derived from an aromatic vinyl monomer, the modified conjugated diene polymer may comprise at least 20 wt %, 30 wt %, 40 wt %, 50 wt %, 55 wt % or 60 wt % and at most 95 wt %, 90 wt % or 80 wt % of the repeating unit derived from the conjugated diene monomer, and may comprise at least 5 wt %, 10 wt % or 20 wt % and at most 80 wt %, 70 wt %, 60 wt %, 55 wt %, 50 wt %, 45 wt % or 40 wt % of the repeating unit derived from the aromatic vinyl monomer. Within these ranges, excellent rolling resistance, wet skid resistance and abrasion resistance can be achieved.

[0115] According to an embodiment of the present invention, the copolymer may be a random copolymer, and in this case, an effect of excellent balance between physical properties may be exhibited. The random copolymer may mean an arrangement of repeating units that form the copolymer in a disordered manner.

[0116] According to the number average molecular weight (Mn) of the modified conjugated diene polymer of the embodiment of the present invention, it can be 10000g / mol to 2000000g / mol, 50000g / mol to 1800000g / mol or 120000g / mol to 1500000g / mol, and the weight average molecular weight (Mw) can be 10000g / mol to 5000000g / mol, 100000g / mol to 3500000g / mol or 120000g / mol to 2000000g / mol.Within these ranges, the excellent effect of rolling resistance and wet skid resistance can be achieved.In another embodiment, the modified conjugated diene polymer can meet the molecular weight distribution (Mw / Mn) of 1.0 to 8.0, 1.0 to 4.0 or 1.0 to 3.5, and within this range, the excellent balance effect between physical properties can be achieved.

[0117] Here, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are molecular weights converted from polystyrene analyzed by gel permeation chromatography (GPC), and the molecular weight distribution (Mw / Mn), also called polydispersity, is calculated as the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn).

[0118] In another embodiment, the Mooney viscosity of the modified conjugated diene-based polymer may be 20 to 150 at 100° C., or 20 to 150 at 140° C., and within this range, excellent effects of processability and productivity may be achieved.

[0119] Here, the Mooney viscosity is measured using a Mooney viscometer, such as a large rotor of MV2000E (ALPHA Technologies) under the conditions of 100° C. and 140° C. and a rotor speed of 2±0.02 rpm. Specifically, the polymer is allowed to stand at room temperature (23±5° C.) for more than 30 minutes, 27±3 g is collected and put into a mold cavity, a press plate is operated, and then the Mooney viscosity is measured while applying torque.

[0120] In addition, the modified conjugated diene polymer may have a vinyl content of 5% by weight or more, 10% by weight or more, or 10% to 60% by weight. Within this range, the glass transition temperature can be controlled within an appropriate range, and excellent effects of rolling resistance, wet skid resistance, and low consumption ratio can be achieved. Here, the vinyl content may refer to the content of the conjugated diene monomer that is not 1,4-added but 1,2-added based on 100% by weight of the conjugated diene copolymer composed of a vinyl monomer and an aromatic vinyl monomer.

[0121] Meanwhile, the terms "derived repeating unit", "derived functional group" and "derived group" used in the present invention may refer to a component or structure derived from a specific material, or the material itself.

[0122] Preparation method of modified conjugated diene polymer

[0123] In addition, the present invention provides a method for preparing the modified conjugated diene polymer.

[0124] The method for preparing a modified conjugated diene polymer according to an embodiment of the present invention is characterized in that it includes: (S1) polymerizing a conjugated diene monomer or an aromatic vinyl monomer and a conjugated diene monomer in a hydrocarbon solvent containing an organic metal compound to prepare a living polymer coupled with an organic metal (step 1); and (S2) reacting the living polymer with a modifier represented by Formula 1 (step 2).

[0125] [Formula 1]

[0126]

[0127] The definitions of the substituents in Formula 1 are the same as those defined above.

[0128] Step 1 is a step for preparing a living polymer coupled with an organic metal compound, and can be performed by polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in a hydrocarbon solvent containing an organic metal compound.

[0129] The hydrocarbon solvent is not particularly limited, and may be, for example, one or more selected from n-pentane, n-hexane, n-heptane, isooctane, cyclohexane, toluene, benzene, and xylene.

[0130] The conjugated diene-based monomer and the aromatic vinyl-based monomer are the same as defined above.

[0131] According to one embodiment of the present invention, the organometallic compound may be used in 0.01 mmol to 10 mmol, 0.05 mmol to 5 mmol, 0.1 mmol to 2 mmol, 0.1 mmol to 1 mmol, or 0.15 mmol to 0.8 mmol, based on a total of 100 g of the monomer.

[0132] The organometallic compound may be, for example, one or more selected from methyllithium, ethyllithium, propyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, hexyllithium, n-decyllithium, tert-octyllithium, phenyllithium, 1-naphthyllithium, n-eicosyllithium, 4-butylphenyllithium, 4-tolyllithium, cyclohexyllithium, 3,5-di-n-heptylcyclohexyllithium, 4-cyclopentyllithium, sodium naphthyl, potassium naphthyl, lithium alkoxide, sodium alkoxide, potassium alkoxide, lithium sulfonate, sodium sulfonate, potassium sulfonate, lithium amide, sodium amide, potassium amide and lithium isopropylamide.

[0133] Meanwhile, the polymerization in step 1 may be performed by including a polar additive, and the polar additive may be added at 0.001 g to 50 g, 0.001 g to 10 g, 0.005 g to 0.2 g, or 0.01 g to 0.2 g based on 100 g of the total monomer.

[0134] In addition, the polar additive can be selected from tetrahydrofuran, 2,2-bis(tetrahydrofuranyl)propane, ether, cyclopentyl ether, dipropyl ether, ethylene dimethyl ether, diethylene glycol, dimethyl ether, tert-butoxyethoxyethane, bis(3-dimethylaminoethyl)ether, (dimethylaminoethyl)ethyl ether, trimethylamine, triethylamine, tripropylamine and tetramethylethylenediamine, particularly one or more of triethylamine or tetramethylethylenediamine. If the polar additive is included, and if the conjugated diene monomer or the conjugated diene monomer and the aromatic vinyl monomer are copolymerized, the difference in their reaction rates can be compensated, and the effect of inducing the easy formation of the random copolymer can be achieved.

[0135] The polymerization in step 1 can be, for example, anionic polymerization, and in a specific embodiment, living anionic polymerization, by which an anionic active part is formed at the polymerization end by the growth polymerization reaction of anions. In addition, the polymerization in step 1 can be temperature-raising polymerization, isothermal polymerization or constant temperature polymerization (adiabatic polymerization). Constant temperature polymerization can refer to a polymerization method including a step of polymerization using self-generated reaction heat without arbitrary application of heat after injecting an organic metal compound, and temperature-raising polymerization can refer to a polymerization method including injecting an organic metal compound and then raising the temperature by arbitrarily applying heat. Isothermal polymerization can refer to such a polymerization method, by adding heat or taking heat after adding an organic metal compound to increase heat, so that the temperature of the polymer is kept constant.

[0136] Furthermore, the polymerization in step 1 can be performed at a temperature ranging from -20°C to 80°C, from 0°C to 80°C, from 10°C to 80°C, or from 10°C to 70°C, for example.

[0137] The living polymer prepared in step 1 may refer to a polymer in which a polymer anion and an organic metal cation are coupled.

[0138] Step 2 is a step of reacting the living polymer with the modifier represented by Formula 1 to prepare a modified conjugated diene-based polymer.

[0139] According to an embodiment of the present invention, the modifier represented by Formula 1 may be used in an amount of 0.05 g to 10 g, 0.05 g to 5 g, for example 0.05 g to 1 g, based on 100 g of the total monomer.

[0140] In addition, according to an embodiment of the present invention, the modifier represented by Formula 1 and the organic metal compound can be used in a molar ratio of 1:0.1 to 1:5.0, a molar ratio of 1:0.1 to 1:4, and within this range, a modification reaction with optimal performance can be performed, and a conjugated diene polymer with a high molecular weight can be obtained.

[0141] The reaction in step 2 is a modification reaction for introducing a functional group derived from a modifying agent, and can be performed at 0° C. to 90° C. for 1 minute to 5 hours.

[0142] In addition, according to an embodiment of the present invention, the method for preparing the modified conjugated diene-based polymer may be performed by a batch type or continuous polymerization method including one or more reactors.

[0143] The method for preparing a modified conjugated diene-based polymer may further include, for example, one or more steps of a recovery step of a solvent and an unreacted monomer after step 2 of the present invention and a drying step when necessary.

[0144] Rubber composition

[0145] Furthermore, the present invention provides a rubber composition comprising the modified conjugated diene-based polymer.

[0146] The rubber composition according to an embodiment of the present invention may include the modified conjugated diene polymer in an amount of 10 wt % or more, 10 wt % to 100 wt %, or 20 wt % to 90 wt %, and within this range, mechanical properties such as tensile strength and wear resistance are excellent, and an excellent balance between physical properties can be achieved.

[0147] In addition, as required, in addition to the modified conjugated diene polymer, the rubber composition may further include other rubber components, and in this case, the other rubber components may be included in an amount of 90% by weight or less relative to the total weight of the rubber composition. In a specific embodiment, the other rubber components may be included in an amount of 1 to 900 parts by weight relative to 100 parts by weight of the modified conjugated diene polymer.

[0148] The rubber component may be, for example, a natural rubber or a synthetic rubber, and may particularly be a natural rubber (NR) including cis-1,4-polyisoprene; a modified natural rubber obtained by modifying or purifying ordinary natural rubber such as epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR) and hydrogenated natural rubber; and synthetic rubbers such as styrene-butadiene copolymer (SBR), polybutadiene (BR), polyisoprene (IR), butyl rubber (IIR), ethylene-propylene copolymer, copolymerized isobutylene-isoprene, chloroprene rubber, copolymerized (ethylene-propylene), copolymerized (styrene-butadiene), copolymerized (styrene-isoprene-butadiene), copolymerized (isoprene-butadiene), copolymerized (ethylene-propylene-diene), polysulfide rubber, acryl rubber, polyurethane rubber, silicone rubber, epichlorohydrin rubber, butyl rubber and halogenated butyl rubber, and any one of them or a mixture of two or more thereof may be used.

[0149] Based on 100 weight portions of the modified conjugated diene polymer of the present invention, the rubber composition may include 0.1 weight portion to 200 weight portions or 10 weight portions to 120 weight portions of filler. The filler may be, for example, a silica-based filler, particularly wet silica (hydrated silicate), dry silica (anhydrous silicate), calcium silicate, aluminum silicate or colloidal silicon dioxide. Preferably, the filler may be wet silica, which has the most significant improvement effect of the destruction characteristics and the compatibility effect of wet grip. In addition, if desired, the rubber composition may further include a carbon-based filler.

[0150] In another embodiment, if silica is used as a filler, a silane coupling agent may be used together to improve the reinforcement and low exothermic properties. Specific examples of the silane coupling agent may include 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-triethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, Formyl tetrasulfide, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzoyl tetrasulfide, 3-triethoxysilylpropylmethacrylate monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, bis(3-diethoxymethylsilylpropyl)tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyl tetrasulfide or dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide, and any one of them or a mixture of two or more thereof may be used. In view of the improvement effect of reinforcing properties, it is preferred to use bis(3-triethoxysilylpropyl)polysulfide or 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide.

[0151] In addition, in the rubber composition according to the embodiment of the present invention, since a modified conjugated diene polymer is used as a rubber component, a functional group having a high affinity with silica in the modified conjugated diene polymer is brought into the active part, so the mixing amount of the silane coupling agent can be less than usual. Therefore, based on 100 parts by weight of silica, the silane coupling agent can be used in an amount of 1 to 20 parts by weight or 5 to 15 parts by weight. Within the above range, the effect as a coupling agent can be fully exhibited, and the effect of preventing the gelation of the rubber component can be achieved.

[0152] The rubber composition according to the embodiment of the present invention can be sulfur cross-linkable, and therefore can further include a vulcanizing agent. The vulcanizing agent can be sulfur powder in particular, and can be included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of rubber components. Within the above range, it is possible to ensure that the required elasticity and intensity of the vulcanized rubber composition, and at the same time, the low fuel consumption ratio can be excellent.

[0153] The rubber composition according to an embodiment of the present invention may contain various additives used in the general rubber industry in addition to the above components, particularly vulcanization accelerators, processing oils, plasticizers, anti-aging agents, scorch retardants, zinc white, stearic acid, thermosetting resins or thermoplastic resins.

[0154] 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, and may include thiazole compounds such as 2-mercaptobenzothiazole (M), dibenzothiazolyl disulfide (DM) and N-cyclohexyl-2-benzothiazolyl sulfenamide (CZ), or guanidine compounds such as diphenylguanidine (DPG).

[0155] Processing oil is used as the softener in rubber composition, and can include for example paraffin, cycloparaffin or aromatic compound. Consider that tensile strength and wear resistance can use aromatic processing oil, consider that hysteresis loss and low temperature performance can use cycloparaffin or paraffin processing oil. Based on the rubber component of 100 weight parts, processing oil can be included with the amount below 100 weight parts. Within the above range, the tensile strength of vulcanized rubber and the deterioration of low heat release performance (low fuel consumption ratio) can be prevented.

[0156] The anti-aging agent may include, for example, 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 condensate of diphenylamine and acetone at high temperature, in an amount of 0.1 to 6 parts by weight based on 100 parts by weight of the rubber component.

[0157] The rubber composition according to an embodiment of the present invention can be obtained by grinding using grinding equipment such as a Banbury mixer, a roll and an internal mixer according to a mixing recipe. The rubber composition having low heat release performance and good wear performance can be obtained by a vulcanization process after a molding process.

[0158] Therefore, the rubber composition can be used to manufacture various components of a tire, such as a tire tread, a tire base, a sidewall, a carcass coating rubber, a belt coating rubber, a bead filler, a bead filler and a bead coating rubber, or to manufacture rubber products in various industries, such as anti-vibration rubber, a belt conveyor and a hose.

[0159] The present invention also provides a tire produced using the rubber composition.

[0160] A tire may be a tire or include a tire tread.

[0161] Example

[0162] Hereinafter, the present invention will be explained in more detail with reference to Examples. However, the Examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

[0163] Preparation Example 1

[0164] 1,4-di(chloromethyl)benzene (3.5 g, 20 mmol), di(3-(trimethoxysilyl)propyl)amine (15.4 g) and triethylamine (8.4 mL) were stirred at 150°C for 6 hours. After the reaction was completed, the temperature was lowered to room temperature, 50 mL of hexane was injected into it, and then stirred for 15 minutes. The solid by-product was removed by diatomaceous earth filter, and the solution and impurities were removed by reduced pressure distillation to obtain a light brown oil. Observation 1 H NMR spectroscopy identified the compound as shown below.

[0165] [Formula 1-1]

[0166]

[0167] 1 H NMR (CDCl3, 500MHz): δ7.24 (s, 4H), 3.56 (d, J=9.2Hz, 40H), 2.48-2.37 (m, 8H), 1.63-1.53 ​​(m, 8H), 0.65-0.56 (m, 8H)

[0168] Preparation Example 2

[0169] 1,3-Di(chloromethyl)benzene (3.5 g, 20 mmol), di(3-(trimethoxysilyl)propyl)amine (15.4 g) and triethylamine (8.4 mL) were stirred at 150°C for 6 hours. After the reaction was completed, the temperature was lowered to room temperature, 50 mL of hexane was injected into it, and then stirred for 15 minutes. The solid by-product was removed by diatomaceous earth filter, and the solution and impurities were removed by vacuum distillation to obtain a light brown oil. Observation 1 H NMR spectroscopy identified the compound as shown below.

[0170] [Formula 1-2]

[0171]

[0172] 1 H NMR (CDCl3, 500MHz): δ7.24 (s, 4H), 3.56 (d, J=9.2Hz, 40H), 2.48-2.37 (m, 8H), 1.63-1.53 ​​(m, 8H), 0.65-0.56 (m, 8H)

[0173] Preparation Example 3

[0174] 2,6-bis(chloromethyl)pyridine (3.5 g, 20 mmol), di(3-(trimethoxysilyl)propyl)amine (15.4 g) and triethylamine (8.4 mL) were stirred at 150°C for 6 hours. After the reaction was completed, the temperature was lowered to room temperature, 50 mL of hexane was injected into it, and then stirred for 15 minutes. The solid by-product was removed by diatomaceous earth filter, and the solution and impurities were removed by vacuum distillation to obtain a light brown oil. Observation 1 H NMR spectroscopy identified the compound as shown below.

[0175] [Formula 1-3]

[0176]

[0177] 1 H NMR (CDCl3, 500MHz): δ7.60 (t, 1H), 7.35 (d, 2H), 3.56 (d, J=9.2Hz, 40H), 2.48-2.37 (m, 8H), 1.63-1.53 ​​(m, 8H), 0.65-0.56 (m, 8H)

[0178] Example 1

[0179] Into a 20L autoclave reactor, 4.733g of n-hexane, 375.0g of styrene, 593.8g of 1,3-butadiene and 1.4g of N,N,N',N-tetramethylethylenediamine (TMEDA) as a polar additive were injected, and 5.0g (10% by weight in hexane) of n-butyllithium was injected, and then the internal temperature of the reactor was adjusted to 40°C, and adiabatic heating reaction was performed. After about 30 minutes, 31.3g of 1,3-butadiene was injected to end-cap the polymer with 1,3-butadiene. Then, the compound represented by formula 1-1 prepared in Preparation Example 1 (1.84g, 2.3mmol) was injected as a modifier and reacted for 20 minutes (molar ratio of [TMEDA]: [catalytic Li] = 3.1: 1, molar ratio of [modifier]: [catalytic Li] = 0.3: 1). Thereafter, the polymerization reaction was quenched using ethanol, and 17 g of a solution in which 30 wt % of Wingstay K as an antioxidant was dissolved in hexane was added. The resulting polymer obtained was put into hot water heated with steam and stirred to remove the solvent, and then, tumble dried to remove the remaining amount of the solvent and water to prepare a modified styrene-butadiene copolymer.

[0180] Example 2

[0181] A modified conjugated diene polymer was prepared by carrying out the same method as in Example 1, except that the compound represented by Formula 1-2 prepared in Preparation Example 2 was injected as a modifier (molar ratio of [TMEDA]:[catalytic Li] = 3.1:1, molar ratio of [modifier]:[catalytic Li] = 0.3:1).

[0182] Example 3

[0183] A modified conjugated diene polymer was prepared by carrying out the same method as in Example 1, except that the compound represented by Formula 1-3 prepared in Preparation Example 3 was injected as a modifier (molar ratio of [TMEDA]:[catalytic Li] = 3.1:1, molar ratio of [modifier]:[catalytic Li] = 0.3:1).

[0184] Comparative Example 1

[0185] A modified conjugated diene polymer was prepared by carrying out the same method as in Example 1, except that SiCl4 was injected as a modifier (molar ratio of [TMEDA]:[catalytic Li] = 3.1:1, molar ratio of [modifier]:[catalytic Li] = 0.48:1).

[0186] Comparative Example 2

[0187] A modified conjugated diene polymer was prepared by carrying out the same method as in Example 1, except that N-methyl-3-(trimethoxysilyl)-N-(3-(trimethoxysilyl)propyl)propan-1-amine was injected as a modifier (molar ratio of [TMEDA]:[catalytic Li] = 3.1:1, molar ratio of [modifier]:[catalytic Li] = 0.35:1).

[0188] *N-Methyl-3-(trimethoxysilyl)-N-(3-(trimethoxysilyl)propyl)propan-1-amine

[0189]

[0190] Comparative Example 3

[0191] A modified conjugated diene polymer was prepared by carrying out the same method as in Example 1, except that tris(3-(trimethoxysilyl)propyl)amine was used as a modifier (molar ratio of [TMEDA]:[catalytic Li] = 3.1:1, molar ratio of [modifier]:[catalytic Li] = 0.36:1).

[0192] *Tris(3-(trimethoxysilyl)propyl)amine

[0193]

[0194] Experimental Example 1

[0195] For the modified conjugated diene polymers prepared in the examples and comparative examples, the styrene unit content and vinyl content in each polymer were measured, and the weight average molecular weight (Mw, ×10 3 g / mol), number average molecular weight (Mn, ×10 3 g / mol), molecular weight distribution (MWD) and Mooney viscosity (MV).

[0196] 1) Styrene bond content and 1,2-vinyl bond content

[0197] The styrene bond content (SM) and 1,2-vinyl bond content (Vi) in each polymer were measured and analyzed using Varian VNMRS 500MHz NMR. When measuring NMR, 1,1,2,2-tetrachloroethane was used as a solvent, and the styrene unit bond content and 1,2-vinyl bond content were calculated as follows: the solvent peak was counted as 6.00 ppm, and 7.2-6.9 ppm was regarded as a random styrene peak, 6.9-6.2 ppm was regarded as a block styrene peak, 5.8-5.1 ppm was regarded as a 1,4-vinyl and 1,2-vinyl peak, and 5.1-4.5 ppm was regarded as a 1,2-vinyl peak.

[0198] 2) Weight average molecular weight, number average molecular weight and molecular weight distribution

[0199] By gel permeation chromatography (GPC) analysis, the weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured, and the molecular weight distribution (MWD, Mw / Mn) was calculated from each molecular weight thus measured.

[0200] Specifically, GPC was performed by using two PLgelOlexis columns (Polymer Laboratories Co.) and one PLgel mixed-C column (Polymer Laboratories Co.) in combination, and the newly replaced columns were all mixed bed type columns. In order to calculate the molecular weight, polystyrene (PS) was used as a GPC standard material.

[0201] 3) Mooney viscosity

[0202] Mooney viscosity (MV, (ML1+4, @100°C MU)) was measured using MV2000 (ALPHA Technologies) at a rotor speed of 2±0.02 rpm at 100°C using a large rotor. In this case, the sample used was left to stand at room temperature (23±5°C) for more than 30 minutes, 27±3 g was collected and put into the mold cavity, the press plate was operated, and the Mooney viscosity was measured for 4 minutes.

[0203] [Table 1]

[0204]

[0205] As the above results, if compared with the comparative example, it is confirmed that the modified conjugated diene polymer of the embodiment using the modifier represented by Formula 1 according to the present invention shows a significantly higher molecular weight than the comparative example, but the increment of Mooney viscosity is relatively not too large. The results show that the modified conjugated diene polymer prepared in the embodiment has a star polymer shape. In addition, it is found that the modified conjugated diene polymer of the embodiment with this structure shows improved processability and excellent wear resistance due to high molecular weight characteristics.

[0206] Experimental Example 2

[0207] In order to comparatively analyze the physical properties of the rubber compositions including the modified conjugated diene-based copolymers prepared in Examples and Comparative Examples and the molded articles produced therefrom, tensile properties, abrasion resistance, and wet skid resistance were measured, respectively.

[0208] 1) Manufacture of rubber samples

[0209] The modified conjugated diene polymers of Examples and Comparative Examples were used as raw material rubbers and kneaded under the kneading conditions shown in the following Table 2. The amounts of the raw materials in Table 2 are expressed in parts by weight based on 100 parts by weight of the raw material rubber.

[0210] [Table 2]

[0211]

[0212] Specifically, the rubber sample was kneaded by first-stage kneading and second-stage kneading. In the first-stage kneading, raw rubber, silica (filler), organic silane coupling agent (X50S, Evonik), process oil (TDAE oil), zinc oxide (ZnO), stearic acid, antioxidant (TMQ (RD)) (2,2,4-trimethyl-1,2-dihydroquinoline polymer), anti-aging agent (6PPD ((dimethylbutyl)-N-phenyl-phenylenediamine) and wax (microcrystalline wax) were kneaded using a Banbury mixer equipped with a temperature control device. In this case, the kneading was controlled. The temperature of the kneading device was set to 100° C., and the first kneaded mixture was obtained at a discharge temperature of 150° C. In the second stage kneading, the first kneaded mixture was cooled to room temperature, and the first kneaded mixture, sulfur powder, rubber accelerator (DPD (diphenylguanidine)) and vulcanization accelerator (CZ (N-cyclohexyl-2-benzothiazolylsulfenamide)) were added to the kneading device and mixed at a temperature of 100° C. or lower to obtain a second kneaded mixture. Then, by curing treatment at 160° C. for 20 minutes, a rubber sample was manufactured.

[0213] 2) Tensile properties

[0214] In order to measure the tensile properties, based on the ASTM412 tensile test method, each specimen was manufactured, and the tensile stress (300% modulus) when the specimen was stretched 300%, the breaking strength (tensile strength) and the elongation of the specimen were measured.

[0215] Specifically, tensile properties were measured at room temperature at a rate of 50 cm / min using a universal testing machine 4204 tensile tester (Instron Co.) In Table 3, the obtained values ​​are shown as indices (%) based on the obtained values ​​of Comparative Example 1, and higher numerical values ​​indicate better results.

[0216] 3) Viscoelastic properties

[0217] The viscoelastic properties were obtained by changing the deformation at each measurement temperature (-60°C to 60°C) at a frequency of 10 Hz in torsion mode using a dynamic mechanical analyzer (TA Corporation), and measuring the tan δ value. The Payne effect is shown as the difference between the minimum and maximum values ​​at deformations of 0.28% to 40%. If the tan δ value at a low temperature of 0°C increases, the wet skid resistance is excellent, and if the tan δ value at a high temperature of 60°C decreases, the hysteresis loss becomes smaller and the rolling resistance (fuel consumption ratio) becomes better. However, in Table 3, the obtained values ​​are shown by an index based on the obtained values ​​of Comparative Example 1, and a higher numerical value indicates a better result.

[0218] 4) Processing performance

[0219] The Mooney viscosity (MV, (ML1+4, MU at 100°C)) of the second kneaded product obtained during the production of 1) the rubber sample was measured, and the processability characteristics of each polymer were comparatively analyzed. In this case, if the Mooney viscosity measurement value decreases, the processability is excellent, but the obtained values ​​in Table 3 are indexed and shown based on the measured values ​​of Comparative Example 1, and if the value increases, the characteristics are excellent.

[0220] Specifically, the measurement was performed using MV2000 (ALPHA Technologies) at a rotor speed of 2±0.02 rpm at 100° C. using a large rotor. Each second kneaded product was left to stand at room temperature (23±5° C.) for more than 30 minutes, 27±3 g was collected and placed in a mold cavity, a press plate was operated, and the measurement was performed for 4 minutes.

[0221] 5) Wear resistance (DIN wear test)

[0222] For each rubber sample, a DIN abrasion test was performed based on ASTM D 5963, and the DIN loss index (loss volume index: ARIA (Abrasion Resistance Index, Method A)) was measured. A higher value indicates a better result.

[0223] [Table 3]

[0224]

[0225] As shown in Table 3, it is confirmed that the modified conjugated diene polymer of the embodiment has the tensile properties, viscoelastic properties, wear resistance and processing properties of balance.Through these results, the modified conjugated diene polymer of the present invention comprises the functional group of the modifier represented by free formula 1, and the affinity with filler is excellent, and this means that due to the structural characteristics of the polymer chain combined with the functional group derived from the modifier, the processability and tensile properties of the rubber composition comprising the modified conjugated diene polymer are improved.Thus, it can be found that the modified conjugated diene polymer of the present invention is modified by the modifier represented by formula 1, and the remarkable effect that the polymer modified by other modifiers with similar structures can not be realized can be obtained.

Claims

1. A modified conjugated diene polymer comprising a repeating unit derived from a conjugated diene monomer and a modified portion derived from a modifier represented by the following formula 1: [Formula 1] In formula 1, A is an arylene group of 6 to 30 carbon atoms, or a heteroarylene group of 2 to 30 carbon atoms containing 1 to 3 N atoms, L1 and L2 are each independently an alkylene group of 1 to 20 carbon atoms, L3 and L4 are each independently an alkylene group of 1 to 20 carbon atoms, and R1 to R6 are each independently an alkyl group of 1 to 10 carbon atoms or an alkoxy group of 1 to 20 carbon atoms, wherein at least one of R1 to R3 is an alkoxy group of 1 to 20 carbon atoms, and at least one of R4 to R6 is an alkoxy group of 1 to 20 carbon atoms.

2. The modified conjugated diene polymer according to claim 1, wherein In Formula 1, A is an arylene group of 6 to 20 carbon atoms, or a heteroarylene group of 3 to 20 carbon atoms containing 1 or 2 N atoms.

3. The modified conjugated diene polymer according to claim 1, wherein In formula 1, L1 and L2 are each independently an alkylene group of 1 to 10 carbon atoms, wherein L1 and L2 are the same, and L3 and L4 are each independently an alkylene group of 1 to 10 carbon atoms, wherein L3 and L4 are the same.

4. The modified conjugated diene polymer according to claim 1, wherein In Formula 1, R1 to R6 are each independently an alkoxy group having 1 to 10 carbon atoms.

5. The modified conjugated diene polymer according to claim 1, wherein The modifier represented by Formula 1 is selected from the compounds represented by the following Formula 1A and Formula 1B: [Formula 1A] [Formula 1B] In Formula 1A and Formula 1B, Definitions of L1 to L4 and R1 to R6 are the same as those in Formula 1.

6. The modified conjugated diene polymer according to claim 1, wherein The modifier represented by Formula 1 is selected from the compounds represented by the following Formulas 1-1 to 1-3: [Formula 1-1] [Formula 1-2] [Formula 1-3] 7 . The modified conjugated diene polymer according to claim 1 , wherein the weight average molecular weight thereof is 10,000 g / mol to 2,000,000 g / mol. 8 . The modified conjugated diene polymer according to claim 1 , which has a molecular weight distribution of 1.0 to 8.

0.

9. A method for preparing a modified conjugated diene polymer, the method comprising: (S1) a step of polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in a hydrocarbon solvent containing an organic metal compound to prepare a living polymer coupled with an organic metal; and (S2) a step of reacting the living polymer with a modifier represented by the following formula 1: [Formula 1] In formula 1, A is an arylene group of 6 to 30 carbon atoms, or a heteroarylene group of 2 to 30 carbon atoms containing 1 to 3 N atoms, L1 and L2 are each independently an alkylene group of 1 to 20 carbon atoms, L3 and L4 are each independently an alkylene group of 1 to 20 carbon atoms, and R1 to R6 are each independently an alkyl group of 1 to 10 carbon atoms or an alkoxy group of 1 to 20 carbon atoms, wherein at least one of R1 to R3 is an alkoxy group of 1 to 20 carbon atoms, and at least one of R4 to R6 is an alkoxy group of 1 to 20 carbon atoms.

10. The method for preparing a modified conjugated diene polymer according to claim 9, wherein: The organic metal compound is used in an amount of 0.01 mmol to 10 mmol based on 100 g in total of the monomer.

11. The method for preparing a modified conjugated diene polymer according to claim 9, wherein: The modifier represented by Formula 1 and the organometallic compound are used in a molar ratio of 1:0.1 to 1:5.0.

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