KR102234507B1 - Preparation method of modified diene polymer and modified diene polymer produced by the same - Google Patents

Abstract

The present invention relates to a method for producing a modified conjugated diene-based polymer having excellent processability, a modified conjugated diene-based polymer prepared therefrom, a rubber composition containing the polymer, and a tire manufactured using the rubber composition.

Description

Preparation method of modified conjugated diene polymer and modified diene polymer produced therefrom {Preparation method of modified diene polymer and modified diene polymer produced by the same}

The present invention relates to a method for producing a modified conjugated diene-based polymer having excellent processability, a modified conjugated diene-based polymer prepared therefrom, a rubber composition containing the polymer, and a tire manufactured using the rubber composition.

In recent years, in accordance with the demand for low fuel consumption for automobiles, a conjugated diene-based polymer having low running resistance, excellent abrasion resistance, and tensile properties as a rubber material for tires, and also having adjustment stability typified by wet skid resistance is required.

In order to reduce the running resistance of the tire, there is a method of reducing the hysteresis loss of the vulcanized rubber. As an evaluation index of the vulcanized rubber, rebound elasticity of 50°C to 80°C, Tan δ, Goodrich heat, and the like are used. That is, a rubber material having high resilience at the above temperature or low Tan δ or Goodrich heat generation is preferable.

As rubber materials with low hysteresis loss, natural rubber, polyisoprene rubber, polybutadiene rubber, and the like are known, but these have a problem of low wet skid resistance. Accordingly, recently, conjugated diene-based (co)polymers such as styrene-butadiene rubber (hereinafter referred to as SBR) or butadiene rubber with controlled cis content (hereinafter referred to as Low Cis-BR) have been prepared by emulsion polymerization or solution polymerization. And is used as rubber for tires. Among them, the greatest advantage of solution polymerization compared to emulsion polymerization is that the vinyl structure content and styrene content that define rubber properties can be arbitrarily adjusted, and molecular weight and physical properties can be adjusted by coupling or modification. Is that it can be adjusted. Therefore, it is easy to change the structure of the final manufactured SBR or Low Cis-BR rubber, reduce the movement of the chain ends by bonding or denaturation of the chain ends, and increase the bonding strength with fillers such as silica or carbon black, which is suitable for solution polymerization. SBR rubber is widely used as a rubber material for tires. When such a solution polymerization SBR is used as a rubber material for tires, the glass transition temperature of the rubber can be increased by increasing the vinyl content in the SBR, so that not only the required properties of the tire such as driving resistance and braking force can be adjusted, but also fuel consumption can be reduced. have.

The solution polymerization SBR is prepared using an anionic polymerization initiator, and the chain ends of the formed polymer are bonded or modified using various modifiers.

For example, U.S. Patent No. 4,397,994 proposes a technique in which the active anion at the chain end of a polymer obtained by polymerizing styrene-butadiene in a non-polar solvent using alkyllithium, which is a monofunctional initiator, is bound using a binder such as a tin compound. I did.

On the other hand, carbon black and silica are used as reinforcing fillers for tire treads. When silica is used as a reinforcing filler, low hysteresis loss and wet skid resistance are improved. However, silica on a hydrophilic surface compared to carbon black on a hydrophobic surface has a disadvantage of poor dispersibility due to low affinity with rubber. It is necessary to use a ring agent.

Accordingly, a method of introducing a functional group having affinity or reactivity with silica at the end of the rubber molecule has been made, but the effect is not sufficient.

In addition, a method of preparing and using a modified polymer through a multistage modification step such as 1st stage and 2nd stage has been proposed. However, in the case of manufacturing through a multistage modification step, there is a large difference in the Mooney Viscosity (MV) stability of the prepared polymer according to the number of functional groups possessed by the modifier used in each step. For example, in the case of a polymer prepared through a multistage modification step using a modifier having an alkoxy group, the molecular weight rapidly increases due to hydrolysis and condensation reactions during storage or transportation, resulting in a large increase in Mooney viscosity. As a result, there is a problem that the workability is deteriorated.

In addition, when silica is used as a filler, in most cases, the blending is not uniform in the process of blending with the filler, resulting in poor processability, and many problems have arisen in molded articles such as tires manufactured therefrom.

Accordingly, there is a need to develop a rubber that not only can provide basic tire properties, but also has excellent blendability with a filler, that is, excellent in balance between physical properties and processability.

US 4,397,994 A

The present invention was conceived to solve the problems of the prior art, and an object of the present invention is to provide a method for producing a modified conjugated diene-based polymer having improved affinity with a filler and excellent processability.

Another object of the present invention is to provide a modified conjugated diene-based polymer having excellent Mooney viscosity stability prepared from the above production method.

In order to solve the above problems, the present invention polymerizes a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in the presence of a polyfunctional anionic polymerization initiator in a hydrocarbon solvent to prepare an active polymer having an alkali metal bonded at both ends. Manufacturing step (step 1); First reacting the polymer with a first denaturant (step 2); And a step of secondary reaction with a second denaturant after the first reaction (step 3), wherein the first denaturant and the second denaturant are compounds represented by the following formula (1) independently of each other. It provides a method of manufacturing.

[Formula 1]

In Formula 1,

R ₁ and R ₂ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms; A C 1 to C 20 monovalent hydrocarbon group including N or O; Or they are connected to each other to form an aliphatic cyclic hydrocarbon group having 3 to 8 carbon atoms,

R ₃ is a monovalent hydrocarbon group having 1 to 20 carbon atoms,

R ₄ is a C 1 to C 20 divalent hydrocarbon group,

R ₅ and R ₆ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or -SiR ₇ R ₈ R ₉ ,

Here, R ₇ to R ₉ are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms.

In addition, in the present invention, two or more conjugated diene-based polymer-derived units are bonded or coupled by a functional group derived from a first modifier, and the two or more conjugated diene-based polymer-derived units each contain a functional group derived from a second modifier at the other end. And, the first denaturant and the second denaturing agent each independently provide a modified conjugated diene-based polymer having excellent Mooney viscosity stability, prepared from the above production method, which is a compound represented by the following formula (1).

[Formula 1]

In Formula 1,

R ₁ and R ₂ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms; A C 1 to C 20 monovalent hydrocarbon group including N or O; Or they are connected to each other to form an aliphatic cyclic hydrocarbon group having 3 to 8 carbon atoms,

R ₃ is a monovalent hydrocarbon group having 1 to 20 carbon atoms,

R ₄ is a C 1 to C 20 divalent hydrocarbon group,

R ₅ and R ₆ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or -SiR ₇ R ₈ R ₉ ,

Here, R ₇ to R ₉ are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms.

The manufacturing method according to the present invention uses an aminoalkoxysilane-based material having two alkoxy groups bonded to silica as a first and second denaturant, and the first and second denaturants are used in a specific ratio to the number of living anions in the polymer chain. A modified conjugated diene-based polymer having excellent Mooney viscosity stability can be prepared in which an amine group is introduced into the intermediate chain and a siloxane group is introduced into both ends by performing the first reaction and the second reaction, respectively.

In addition, the modified conjugated diene-based polymer prepared by the production method of the present invention has an amine group introduced into the intermediate chain and a siloxane group introduced at both ends, thereby having excellent affinity with carbon black as well as silica, Mooney viscosity can also be excellent in stability. Accordingly, since the modified conjugated diene-based polymer may have excellent processability, a processed product (eg, tire) manufactured from a rubber composition including the modified conjugated diene polymer may have excellent tensile strength, abrasion resistance, and viscoelastic properties.

Hereinafter, the present invention will be described in more detail to aid understanding of the present invention.

The terms or words used in the specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventor may appropriately define the concept of terms in order to describe his own invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that there is.

In the present invention, the modified conjugated diene-based polymer may include two or more conjugated diene-based polymer-derived units, wherein one end of the unit derived from one conjugated diene-based polymer is bonded to one end of the unit derived from another conjugated diene-based polymer or It may be coupled, and the bonding or coupling may be due to a functional group derived from the first denaturant.

Here, the'conjugated diene-based polymer-derived unit' may be a polymer formed by polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer.

In the present invention, the intermediate chain of the polymer may represent a portion or a portion in which two or more conjugated diene-based polymer-derived units are bonded or coupled.

The present invention provides a method for producing a modified conjugated diene polymer having excellent blending properties with a filler and excellent processability.

The production method according to an embodiment of the present invention is an active polymer in which alkali metals are bonded at both ends by polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in the presence of a polyfunctional anionic polymerization initiator in a hydrocarbon solvent. Manufacturing a step (step 1); First reacting the polymer with a first denaturant (step 2); And performing a second reaction with a second denaturant after the first reaction (step 3), wherein the first denaturant and the second denaturant are independently of each other a compound represented by the following formula (1).

[Formula 1]

In Formula 1,

R ₁ and R ₂ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms; A C 1 to C 20 monovalent hydrocarbon group including N or O; Or they are connected to each other to form an aliphatic cyclic hydrocarbon group having 3 to 8 carbon atoms,

R ₃ is a monovalent hydrocarbon group having 1 to 20 carbon atoms,

R ₄ is a C 1 to C 20 divalent hydrocarbon group,

R ₅ and R ₆ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or -SiR ₇ R ₈ R ₉ ,

Here, R ₇ to R ₉ are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms.

Step 1 is a step for preparing an active polymer in which an alkali metal is bonded to both ends, and is performed by polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in the presence of a polyfunctional anionic polymerization initiator in a hydrocarbon solvent. I can.

In the present invention, the term “active polymer in which an alkali metal is bonded to both ends” may refer to a polymer in which anions and alkali metal cations at both ends of the polymer are bonded.

In the present invention, the polymer may be a homopolymer derived from a conjugated diene-based monomer, or may be a copolymer derived from a conjugated diene-based monomer and an aromatic vinyl-based monomer. When the polymer is a copolymer, the copolymer may be a random copolymer.

In the present invention, the term "random copolymer" refers to a random arrangement of constituent units constituting the copolymer.

The conjugated diene-based monomer is not particularly limited, but, for example, 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-1,3-octadiene, isoprene and 2-phenyl It may be one or more selected from the group consisting of -1,3-butadiene.

The conjugated diene-based monomer may be used alone or together with an aromatic vinyl-based monomer. When the conjugated diene-based monomer is used together with an aromatic vinyl-based monomer, the conjugated diene-based monomer may be used in an amount of 60% to 90% by weight based on 100% by weight of the total monomer. Specifically, the conjugated diene-based monomer may be used in an amount of 60% to 85% by weight.

The aromatic vinyl-based monomer is not particularly limited, for example, styrene, α-methyl styrene, 3-methyl styrene, 4-methyl styrene, 4-propylstyrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4-(p -Methylphenyl) styrene and 1-vinyl-5-hexylnaphthalene may be one or more selected from the group consisting of.

The aromatic vinyl-based monomer may be used in an amount of 10% to 40% by weight based on 100% by weight of the total monomer. Specifically, the aromatic vinyl-based monomer may be used in an amount of 15% to 40% by weight.

The hydrocarbon solvent is not particularly limited, but may be, for example, one or more selected from the group consisting of n-pentane, n-hexane, n-heptane, isooctane, cyclohexane, toluene, benzene, and xylene.

The polyfunctional anionic polymerization initiator may be used in an amount of 0.1 mmol to 5.0 mmol based on a total of 100 g of monomers.

The polyfunctional anionic polymerization initiator may be prepared by reacting an aromatic compound and an organolithium compound in a hydrocarbon solvent. In this case, the aromatic compound and the organic lithium compound may be reacted in a molar ratio of 1:1 to 1:2.

The aromatic compound used in the preparation of the polyfunctional anionic polymerization initiator is o-diisopropenyl benzene, m-diisopropenyl benzene, p-diisopropenyl benzene, o-divinyl benzene, m-divinyl benzene, p-divinyl benzene, 1,2,4-trivinyl benzene, 1,2-vinyl-3,4-dimethylbenzene, 1,3-divinyl naphthalene, 1,3,5-trivinylnaphthalene, 2,4 -Consisting of divinylbiphenyl, 3,5,4'-trivinyl biphenyl, 1,2-divinyl-3,4-dimethylbenzene and 1,5,6-trivinyl-3,7-diethyl naphthalene It may be one or more selected from the group, but is not limited thereto.

The organolithium compound used in the preparation of the polyfunctional anionic polymerization initiator is ethyllithium, propyllithium, n-butyllithium, s-butyllithium, t-butyllithium, hexyllithium, phenyllithium, lithium dimethyl amide and lithium isopropylamide. It may be one or more selected from the group consisting of, but is not limited thereto.

The hydrocarbon solvent used in the preparation of the polyfunctional anionic polymerization initiator may be as described above.

In addition, when preparing the polyfunctional anionic polymerization initiator, a Lewis base may be further used to promote or stabilize the formation of the initiator. In this case, the Lewis base is not particularly limited, but may be used in an amount of 50,000 ppm to 200,000 ppm relative to the hydrocarbon solvent.

The Lewis base may be, for example, a tertiary amine, a tertiary diamine, a chain or cyclic ether. The tertiary amine is trimethylamine, triethylamine, methyl diethyl amine, 1,1-dimethoxy trimethylamine, 1,1-diethoxy trimethylamine, 1,1-diethoxy triethylamine, N,N-dimethyl Formamide diisopropyl acetal, N,N-dimethylformamide dicyclohexyl acetal, and the like.

The tertiary diamine is N,N,N',N'-tetramethyl diaminomethane, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethypropane diamine , N,N,N',N'-tetramethyl diaminobutane, N,N,N',N'-tetramethyl diaminopentane, N,N,N',N'-tetramethyl hexanediamine, dipiperi Dinopentane, dipiperidino ethane, and the like.

The chain ether may be dimethyl ether, diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene dimethyl ether, or the like.

The cyclic ethers are tetrahydrofuran, bis(2-oxolanyl)ethane, 2,2-bis(2-oxolanyl)propane, 1,1-bis(2-oxolanyl)ethane, 2,2- Bis(2-oxolanyl)butane, 2,2-bis(5-methyl-2-oxolanyl)propane, 2,2-bis(3,4,5-trimethyl-2-oxolanyl)propane, etc. I can.

In addition, the polyfunctional anionic polymerization initiator may be prepared by reacting under a temperature of 50°C or less, specifically -20°C to 30°C.

The polymerization of step 1 may be performed by further adding a polar additive, and the polar additive may be added in an amount of 0.01 g to 2.0 g based on a total of 100 g of monomers. Specifically, the polar additive may be added in an amount of 0.05 g to 1.0 g, more specifically 0.03 g to 0.5 g, based on 100 g of the total monomer.

The polar additives include tetrahydrofuran, ditetrahydroprilpropane, diethyl ether, cycloamal ether, dipropyl ether, ethylene dimethyl ether, ethylene dimethyl ether, diethylene glycol, dimethyl ether, tertiary butoxyethoxyethane bis ( It may be one or more selected from the group consisting of 3-dimethylaminoethyl) ether, (dimethylaminoethyl) ethyl ether, trimethylamine, triethylamine, tripropylamine, and tetramethylethylenediamine.

The manufacturing method according to an embodiment of the present invention is to make it easy to form a random copolymer by compensating for the difference in reaction rate when the conjugated diene-based monomer and the aromatic vinyl-based monomer are copolymerized by using the polar additive. You can induce it.

The polymerization of step 1 may be performed through temperature-rising polymerization or constant-temperature polymerization.

Here, temperature-raising polymerization refers to a polymerization method including the step of increasing the reaction temperature by optionally applying heat after adding the polyfunctional anionic polymerization initiator, and the constant temperature polymerization is optionally heating after the polyfunctional anionic polymerization initiator is added. It shows a polymerization method in which no is added.

The polymerization may be performed at a temperature range of -20°C to 150°C, specifically 0°C to 120°C, and more specifically 50°C to 100°C.

Step 2 is a step of first reacting the active polymer with a first modifier in order to introduce an amine group into the intermediate chain of the active polymer to which the alkali metal is bonded at both ends.

The first denaturant may be the same compound as the second denaturant to be described later, or may be a different compound. Specifically, the first denaturant may be the same compound as the second denaturant, and may be a compound represented by Formula 1 above.

Specifically, the first denaturing agent in Formula 1, R ₁ and R ₂ are each independently an alkyl group having 1 to 10 carbon atoms; Alternatively, they may be connected to each other to form an aliphatic cyclic hydrocarbon group having 3 to 6 carbon atoms, and when R ₁ and R ₂ form an aliphatic cyclic hydrocarbon group, the cyclic hydrocarbon group may be substituted with at least one alkyl group having 1 to 3 carbon atoms. .

In addition, in Formula 1, R ₅ and R ₆ may be independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or -SiR ₇ R ₈ R ₉ , and R ₅ and R ₆ may be simultaneously -SiR ₇ R ₈ R _{In the} case of 9, each R ₉ may be connected to each other to form a cyclic hydrocarbon.

Specifically, in Formula 1, R ₁ and R ₂ are each independently an alkyl group having 1 to 6 carbon atoms; Or they may be connected to each other to form an aliphatic cyclic hydrocarbon group having 3 to 6 carbon atoms, and when R ₁ and R ₂ form a cyclic hydrocarbon group, the cyclic hydrocarbon group may be substituted with at least one alkyl group having 1 to 3 carbon atoms, and R ₃ is an alkyl group having 1 to 6 carbon atoms, R ₄ is an alkylene group having 1 to 10 carbon atoms, and R ₅ and R ₆ may each independently be an alkyl group having 1 to 6 carbon atoms.

More specifically, the compound represented by Chemical Formula 1 is 3-diethoxy(methyl)silyl)-N,N-diethylpropan-2-amine (3-(diethoxy(methyl)silyl)-N,N-diethylpropan -2-amine), or 2-(N,N-dimethylaminopropyl)-2,5,5-trimethyl-1,3,2-dioxasilinane (2-(N,N-dimethylaminopropyl)-2, 5,5-trimethyl-1,3,2-dioxasilinane).

The first modifier may be used in an amount of 0.1 moles to 1.0 moles relative to 1 mole of the polyfunctional anionic polymerization initiator. Specifically, the first modifier may be used in an amount of 0.25 mol to 1.0 mol relative to 1 mol of the polyfunctional anionic polymerization initiator.

In addition, the first modifier may be used by adjusting the number of siloxane groups in the first modifier relative to the number of ends of the polymer chain to match a desired number, and specifically, 10% of the number of living anions at the end of the polymer chain It may be used in an amount of to 100%. More specifically, it may be used in an amount of 20% to 100%, more specifically 25% to 100%.

The manufacturing method according to an embodiment of the present invention uses a first modifier having two functional groups (alkoxy groups) as described above in a specific ratio relative to the polyfunctional anionic polymerization initiator. An amine group derived from a modifier can be introduced.

Specifically, when the first denaturant is used in an amount such that all functional groups of the first denaturant, such as an alkoxy group and the living anion of the polymer chain, react, ethanol is desorbed as much as the alkoxy group during the first reaction and intermediate A polymer in which an amine group is bonded to the chain can be prepared.

This makes it possible to prepare an active polymer in which an alkali metal is bonded to both ends and an amine group derived from the first modifier is introduced into the intermediate chain.

That is, in the active polymer prepared by step 2, two or more active polymers each react with one first denaturant, so that the functional group derived from the first denaturant is simultaneously included in the intermediate chain, but each other end is still an alkali metal Each of these may be bound active polymers.

In step 3, in order to prepare a modified conjugated diene-based polymer in which an amine group is introduced into the intermediate chain and a siloxane group is introduced at both ends, the active polymer into which the functional group derived from the first modifier is introduced is subjected to a secondary reaction with a second modifier. . In this case, the second denaturant may be the same as the first denaturant or a different compound as described above. The specific type of the second denaturant may be the same as the above-described first denaturant.

The second denaturant may be used in an amount of 1 mol to 10 mol relative to 1 mol of the first denaturant.

The first and second reactions are denaturation reactions for introducing functional groups to the intermediate chain and both ends of the polymer, and each of the first and second reactions is performed in a temperature range of 0°C to 100°C for 1 minute to 5 minutes. It could be something to do for hours.

The manufacturing method according to an embodiment of the present invention can prepare a modified conjugated diene-based polymer in which a functional group is introduced into the intermediate chain and both ends through the first reaction and the second reaction.

In addition, the present invention provides a modified conjugated diene-based polymer prepared from the above production method.

The modified conjugated diene-based polymer according to an embodiment of the present invention may be a modified conjugated diene homopolymer or a modified conjugated diene-based copolymer, and the copolymer may be a modified styrene-butadiene copolymer.

The modified conjugated diene-based polymer may have a structure in which the functional groups derived from the first and second denaturing agents are introduced into the intermediate chain and both ends by the method as described above, and specifically, two or more conjugated diene-based polymers The derived units are simultaneously bonded or coupled by a functional group derived from a first denaturant, and the units derived from the two or more conjugated diene-based polymers each contain a functional group derived from a second denaturant at the other end, and the first denaturant and the second denaturant Independently of each other, it may be a compound represented by Formula 1. For example, the polymer may contain 0.05 mmol to 5.0 mmol of an amine group per 100 g in the intermediate chain, and may contain a unit containing 0.2 mmol to 20.0 mmol of siloxane group per 100 g of the polymer at the end of the polymer.

In addition, the modified conjugated diene-based polymer may have a Mooney viscosity difference (Δ MV) represented by Equation 1 below of 10 to -30.

[Equation 1]

△ MV = CMV-PMV

In Equation 1, CMV (compound mooney viscosity) is the Mooney viscosity of a blend containing a modified conjugated diene-based polymer, a filler, and a crosslinking agent, and PMV (polymer mooney viscosity) is the Mooney viscosity of the modified conjugated diene-based polymer.

At this time, the modified conjugated diene-based polymer may have a Mooney viscosity of 20 or more, specifically 30 to 150, and more specifically 50 to 100.

In addition, the difference in Mooney viscosity indicates the blending properties of the modified conjugated diene-based polymer, that is, the ease of blending with a filler. It means that when a modified conjugated diene-based polymer is used, processability can be excellent.

Here, the blend may be a mixture comprising a modified conjugated diene polymer, a filler, and a crosslinking agent, and specifically, may be a second blend described in Experimental Examples 2 and 1) Preparation of a crosslinked rubber to be described later. In addition, the Mooney viscosity was determined after leaving the modified conjugated diene-based polymer or blend at room temperature (23±5°C) for 30 minutes or more under conditions of 100°C and Rotor Speed 2±0.02rpm using a large rotor of Monsanto's MV2000E. ±3g was collected, filled inside the die cavity, and measured while applying torque by operating a platen.

The modified conjugated diene-based polymer may have a number average molecular weight of 1,000 g/mol to 2,000,000 g/mol, specifically 10,000 g/mol to 1,000,000 g/mol, more specifically 100,000 g/mol to 500,000 g/mol. .

The modified conjugated diene-based polymer may have a vinyl content of 15% or more, specifically 20% or more, more specifically 25% to 70%, and the glass transition temperature of the polymer is adjusted within this range to be applied to a tire. Not only can it satisfy the physical properties required of the tire, such as running resistance and braking force, but also has the effect of reducing fuel consumption. At this time, the vinyl content refers to the content of the 1,2-added conjugated diene-based monomer rather than 1,4-added based on 100% by weight of the conjugated diene-based monomer.

The modified conjugated diene-based polymer may have a molecular weight distribution of 1.0 to 5.0, specifically 1.3 to 4.0, and more specifically 1.5 to 3.0.

The modified conjugated diene-based polymer has viscoelastic properties, and when measured at 10 Hz through DMA after mixing with silica, the Tan δ value at 60°C (Tanδ at 60°C) may be 0.15 to 0.10, or 0.13 to 0.08 days. In this range, compared to the conventional invention, the driving resistance or the rolling resistance (RR) is greatly improved.

In addition, the present invention provides a rubber composition comprising the modified conjugated diene-based polymer.

The rubber composition may include a modified conjugated diene-based polymer in an amount of 0.1% to 100% by weight, specifically 20% to 90% by weight.

In addition, the rubber composition may further include other rubber components as necessary in addition to the modified conjugated diene-based polymer, and the rubber component may be included in an amount of 90% by weight or less based on the total weight of the rubber composition. Specifically, it may be included in an amount of 1 to 90 parts by weight based on 100 parts by weight of the modified conjugated diene-based copolymer.

The rubber component may be a natural rubber or a synthetic rubber, for example, the rubber component is a natural rubber (NR) including cis-1,4-polyisoprene; Modified natural rubber such as epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), hydrogenated natural rubber, etc. obtained by modifying or purifying the general natural rubber; Styrene-butadiene copolymer (SBR), polybutadiene (BR), polyisoprene (IR), butyl rubber (IIR), ethylene-propylene copolymer, polyisobutylene-co-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 -Co-diene), polysulfide rubber, acrylic rubber, urethane rubber, silicone rubber, epichlorohydrin rubber, butyl rubber, halogenated butyl rubber, etc. may be synthetic rubber, any one or a mixture of two or more of them may be used. have.

In addition, the rubber composition may include 0.1 parts by weight to 200 parts by weight of a filler based on 100 parts by weight of the modified conjugated diene polymer, and specifically, may include 0.1 parts by weight to 150 parts by weight of the filler. The filler may be a silica-based filler, a carbon black-based filler, or a combination thereof.

The carbon black-based filler is not particularly limited, but may have a nitrogen adsorption specific surface area (measured in accordance with N2SA, JIS K 6217-2:2001) of 20 m 2 /g to 250 m 2 /g. In addition, the carbon black may have a dibutylphthalate oil absorption (DBP) of 80 cc/100g to 200 cc/100g. When the nitrogen adsorption specific surface area of the carbon black ^{exceeds 250 m 2} /g, the processability of the rubber composition may be deteriorated, and when it is ^{less than 20 m 2} /g, the reinforcing performance by the carbon black may be insignificant. In addition, when the DBP oil absorption amount of the carbon black exceeds 200 cc/100 g, the processability of the rubber composition may be deteriorated, and when it is less than 80 cc/100 g, the reinforcing performance by the carbon black may be insignificant.

In addition, the silica is not particularly limited, but may be, for example, wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, or colloidal silica. Specifically, the silica may be a wet silica having the most remarkable effect of improving fracture properties and having both wet grip properties. In addition, the silica has a nitrogen surface area per gram (N2SA) of 120 m2/g to 180 m2/g, and a specific surface area of CTAB (cetyl trimethyl ammonium bromide) adsorption from 100 m2/g to 200 m2/g Can be When the nitrogen adsorption specific surface area of the silica is less than 120 m 2 /g, the reinforcing performance by silica may be deteriorated, and when it exceeds 180 m 2 /g, the workability of the rubber composition may be deteriorated. In addition, when the CTAB adsorption specific surface area of the silica is less than 100 m 2 /g, the reinforcing performance by silica as a filler may be deteriorated, and when it exceeds 200 m 2 /g, the workability of the rubber composition may be reduced.

Meanwhile, when silica is used as the filler, a silane coupling agent may be used together to improve reinforcement and low heat generation.

Specifically, as the silane coupling agent, 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-dimethylthiocarbamoyltetrasulfur Feed, 3-triethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-trimethoxysilyl Propylbenzothiazolyltetrasulfide, 3-triethoxysilylpropylbenzolyltetrasulfide, 3-triethoxysilylpropylmethacrylate monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, bis (3-diethoxymethylsilylpropyl)tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide or dimethoxymethylsilylpropylbenzothiazolyl Tetrasulfide and the like, and any one or a mixture of two or more of them may be used. More specifically, when considering the effect of improving reinforcement, the silane coupling agent may be bis(3-triethoxysilylpropyl)polysulfide or 3-trimethoxysilylpropylbenzothiazyltetrasulfide.

In addition, in the rubber composition according to an embodiment of the present invention, since a modified conjugated diene-based polymer in which a functional group having high affinity with a filler is introduced in the active site as a rubber component is used, the amount of the silane coupling agent is It can be reduced than the usual case. Specifically, the silane coupling agent may be used in an amount of 1 to 20 parts by weight based on 100 parts by weight of the filler. When used in the above range, gelation of the rubber component can be prevented while the effect as a coupling agent is sufficiently exhibited. More specifically, the silane coupling agent may be used in an amount of 5 parts by weight to 15 parts by weight based on 100 parts by weight of silica.

In addition, the rubber composition according to an embodiment of the present invention may be sulfur crosslinkable, and thus may further include a vulcanizing agent.

The vulcanizing agent may be specifically sulfur powder, and may be included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the rubber component. When included in the above content range, the required elastic modulus and strength of the vulcanized rubber composition can be secured, and at the same time, low fuel economy can be obtained.

In addition, in addition to the above components, the rubber composition according to an embodiment of the present invention includes various additives commonly used in the rubber industry, specifically, a vulcanization accelerator, a process oil, a plasticizer, an anti-aging agent, an anti-scorch agent, and a zinc oxide. , Stearic acid, a thermosetting resin, or a thermoplastic resin may be further included.

The vulcanization accelerator is not particularly limited, and specifically, M (2-mercaptobenzothiazole), DM (dibenzothiazyl disulfide), CZ (N-cyclohexyl-2-benzothiazylsulfenamide), etc. A thiazole-based compound or a guanidine-based compound such as DPG (diphenylguanidine) 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.

In addition, the process oil acts as a softening agent in the rubber composition, and may specifically be a paraffinic, naphthenic, or aromatic compound. More specifically, when considering tensile strength and abrasion resistance, the aromatic process oil is hysteresis. In consideration of loss and low temperature characteristics, a naphthenic or paraffinic process oil may be used. The process oil may be included in an amount of 100 parts by weight or less based on 100 parts by weight of the rubber component, and when included in the amount, it is possible to prevent a decrease in tensile strength and low heat generation (low fuel consumption) of the vulcanized rubber.

In addition, as the anti-aging agent, specifically, N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, 6- And oxy-2,2,4-trimethyl-1,2-dihydroquinoline, or a high-temperature condensation product of diphenylamine and acetone. The anti-aging agent may be used in an amount of 0.1 to 6 parts by weight based on 100 parts by weight of the rubber component.

The rubber composition according to an embodiment of the present invention can be obtained by kneading using a kneader such as a Banbury mixer, a roll, or an internal mixer according to the above formulation, and has low heat generation and abrasion resistance by a vulcanization process after molding processing. This excellent rubber composition can be obtained.

Accordingly, the rubber composition may include tire treads, under treads, side walls, carcass coated rubbers, belt coated rubbers, bead fillers, pansies, or bead coated rubbers, and other tire members, anti-vibration rubber, belt conveyors, hoses, etc. It can be useful in the manufacture of various industrial rubber products.

The molded article manufactured using the rubber composition may include a tire or a tire tread.

Hereinafter, the present invention will be described in more detail by examples and experimental examples. However, the following Examples and Experimental Examples are for illustrative purposes only, and the scope of the present invention is not limited thereto.

Manufacturing example : Multifunctionality Anionic polymerization initiator (t- buLi /1,3- diisopropenylbenzene adduct)

A 2.5 L reactor equipped with a stirrer and jacket was previously dried with nitrogen and then adjusted to -10°C. Triethylamine 47.5 g (99.5%, 0.467 mol), t-butyllithium 332.5 g (18%, 0.934 mol), and cyclohexane 466.6 g were sequentially added thereto, followed by stirring and mixing. Thereafter, 76.2 g (97%, 0.467 mol) of 1,3-diisopropenylbenzene was slowly added, and when the addition was completed, the mixture was stirred at room temperature for 2 hours to prepare 922.8 g (14.5%) of a polyfunctional anionic polymerization initiator.

Example 1

Normal hexane 2000 g/hr, butadiene 292 g/hr, styrene 108 g/hr, and polar additives after drying with nitrogen and removing impurities such as moisture in advance by connecting four 6 L reactors equipped with a stirrer and jacket in series. 0.82 g/hr of TMEDA (tetramethylethylenediamine) was added to the first reactor. Here, the polyfunctional anionic polymerization initiator (molecular weight: 288.37 g/mol) prepared in Preparation Example was continuously added to the reactor so that it became 0.90 g/hr based on the amount of lithium initiator added. At this time, the temperature inside the reactor was maintained at 80° C. and the reaction was carried out for 40 minutes. Then, a certain amount of the reactant was continuously transferred to the second reactor, and the solid content (TSC, Total Solid Content) in the reactor reactant was measured while passing through the second reactor to confirm that butadiene and styrene were consumed by 98% or more. At this time, the reaction temperature in the second reactor was 80°C and the reaction time was 60 minutes. Thereafter, the reactant was continuously transferred to the second reactor to the third reactor, and 3-(diethoxy(methyl)silyl)-N,N-diethylpropan-2-amine (molecular weight: 247.45 g/mol, two alkoxy groups) ) Was added at 0.193 g/hr, which is 0.25 mol of the polymerization initiator, and a coupling reaction (first modification reaction) was performed while maintaining the temperature at 75°C for 40 minutes. Thereafter, it was transferred to the fourth reactor and 3-(diethoxy(methyl)silyl)-N,N-diethylpropan-1-amine was added to the reactant from the third reactor at 1.158 g/hr, which is 1.5 mol of the polymerization initiator. Then, while maintaining the temperature at 75° C. for 30 minutes, a denaturation reaction (secondary denaturation reaction) was performed. After adding 2,6-di-t-butyl-p-cresol (BHT) at 4.0 g/hr to the reactant coming out of the fourth reactor, the solvent was removed through steam stripping, and a 6-inch Hot Roll (110° C.) By drying for 4 minutes, a modified styrene-butadiene copolymer was prepared.

Example 2

The polyfunctional anionic polymerization initiator prepared in Preparation Example was added at 0.92 g/hr and the polar additive was added at 0.84 g/hr, and in the first modification reaction, 3-(diethoxy(methyl)silyl)-N,N-diethyl Propan-2-amine is added at 0.395 g/hr, which is 0.5 mol compared to the polymerization initiator, and 3-(diethoxy(methyl)silyl)-N,N-diethylpropan-2-amine compared to the polymerization initiator in the secondary denaturation reaction. A modified styrene-butadiene copolymer was prepared in the same manner as in Example 1, except that 1.0 mol of 0.790 g/hr was added.

Example 3

The polyfunctional anionic polymerization initiator prepared in Preparation Example was added at 0.84 g/hr and the polar additive was added at 0.75 g/hr, and in the first modification reaction, 3-(diethoxy(methyl)silyl)-N,N-diethyl Propan-2-amine was added at 0.721 g/hr, which is 1.0 mol relative to the polymerization initiator, and 3-(diethoxy(methyl)silyl)-N,N-diethylpropan-2-amine was added to the polymerization initiator in the secondary denaturation reaction. A modified styrene-butadiene copolymer was prepared in the same manner as in Example 1, except that 1.0 mol, 0.721 g/hr, was added.

Comparative Example 1

Four 6 L reactors equipped with a stirrer and jacket are connected in series and dried with nitrogen beforehand, and then butadiene 292 g/hr, styrene 108 g/hr, hexane 2000 g/hr, and TMEDA (tetra Methylethylenediamine) 0.75 g/hr was added to the first reactor. Here, the polyfunctional anionic polymerization initiator prepared in Preparation Example was continuously added to the reactor so as to be 0.84 g/hr based on the amount of lithium initiator added. At this time, the temperature inside the reactor was maintained at 80° C. and the reaction was performed for 40 minutes. Subsequently, a certain amount of the reactant was continuously transferred to the second reactor, and the solid content (TSC, Total Solid Content) in the reactor reactant was measured while passing through the second reactor to confirm that butadiene and styrene were consumed by 98% or more. At this time, the reaction temperature in the second reactor was 80°C and the reaction time was 60 minutes. Thereafter, the reactants were continuously transferred to the second reactor to the third reactor, and then transferred to the fourth reactor, and reacted while maintaining the temperature at 75°C for 30 minutes. After adding 2,6-di-t-butyl-p-cresol (BHT) at 4.0 g/hr to the reactant coming out of the fourth reactor, the solvent was removed through steam stripping, and a 6-inch Hot Roll (110° C.) It was dried for 4 minutes by using to prepare an unmodified styrene-butadiene copolymer.

Comparative Example 2

The polyfunctional anionic polymerization initiator prepared in Preparation Example was added at 0.90 g/hr, and the polar additive was added at 0.82 g/hr, and 3-(diethoxy(methyl)silyl) without performing a coupling reaction (first modification reaction). )-N,N-diethylpropan-1-amine was added to the reactant from the third reactor at 1.54 g/hr, which is 2.0 times the molar ratio of the polymerization initiator, and only the second denaturation reaction was performed in the fourth reactor. A modified styrene-butadiene copolymer was prepared through the same method as in Example 1.

Comparative Example 3

The polyfunctional anionic polymerization initiator prepared in Preparation Example was added at 0.95 g/hr and a polar additive at 0.96 g/hr, and 3-(diethoxy(methyl)silyl)-N,N-diethylpropan-2-amine Was added at 0.408 g/hr, which is 0.5 mol of the polymerization initiator, to perform a coupling reaction, and 1-(3-triethoxysilyl)propyl)-2,2,5,5-tetramethyl -2,5-disila-1azacyclopentane (molecular weight: 363.72 g/mol, number of alkoxy groups) was added at 1.20 g/hr, which is 1.0 mol of the polymerization initiator, except that the secondary denaturation reaction was carried out. A modified styrene-butadiene copolymer was prepared through the same method as in Example 1.

Comparative Example 4

The polyfunctional anionic polymerization initiator prepared in Preparation Example was added at 0.92 g/hr and a polar additive at 0.84 g/hr, and 3-(diethoxy(methyl)silyl)-N,N-diethylpropan-2-amine Was added at 0.395 g/hr, which is 0.5 mol of the polymerization initiator, to perform a coupling reaction (first modification reaction), and 3-(diethoxymethylsilyl)-N-(3-(diethoxy) was added to the reaction product from the third reactor. Except for performing the secondary denaturation reaction by adding methylsilyl)propyl-N-methylpropan-1-amine (molecular weight: 379.69 g/mol, number of alkoxy groups of 4) at 1.21 g/hr, which is 1.0 mol of the polymerization initiator. Was prepared a modified styrene-butadiene copolymer through the same method as in Example 1.

Experimental Example 1

Microstructure analysis, Mooney viscosity, and molecular weight characteristics of the modified styrene-butadiene copolymer prepared in Examples 1 to 3 and Comparative Examples 2 to 4 and the styrene-butadiene copolymer prepared in Comparative Example 1 were measured. . The results are shown in Table 1 below.

1) Microstructure analysis

Microstructure analysis was measured using Varian VNMRS 500 Mhz NMR, and 1,1,2,2-tetrachloroethane D2 (Cambridge Isotope) was used as a solvent.

2) Mooney viscosity

The Mooney viscosity was measured by collecting the reactants that completed the second reaction in the second reactor during the preparation of each copolymer, the reactants that completed the third reaction in the third reactor, and each of the final prepared copolymers, respectively, and the Mooney viscosity was MV- Using 2000E (Monsanto), a rotor speed of 2±0.02 rpm and a large rotor were used to measure ML (1+4 at 100°C). At this time, the sample was left at room temperature (23±3℃) for at least 30 minutes, then 27±3 g was collected, filled in the die cavity, and measured by operating the platen.

3) Mooney viscosity stability evaluation

Mooney viscosity stability was measured by the same method as the Mooney viscosity measurement method described above after each copolymer was placed in an aging oven at 70° C. and subjected to heat aging for 24 hours. Before heat aging the thus measured value, stability was evaluated by the difference between the Mooney viscosity of the final prepared copolymer. In this case, the smaller the difference, the better the Mooney viscosity stability.

4) Molecular weight characteristics

The molecular weight characteristics of each of the copolymers were compared by measuring the weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw/Mn).

Specifically, each copolymer was dissolved in tetrahydrofuran (THF) for 30 minutes under the condition of 40° C., and then loaded and flowed through gel permeation chromatography (GPC). At this time, the column was used in combination with two PLgel Olexis columns and one PLgel mixed-C column manufactured by Polymer Laboratories. In addition, all of the newly replaced columns used a mixed bed type column, and polystyrene was used as a gel permeation chromatography standard material (GPC STandard material).

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Transformation or not Secondary degeneration Secondary degeneration Secondary degeneration Unmodified Primary degeneration Secondary degeneration Secondary degeneration Microstructure Analysis (NMR) Styrene
(SM, wt%) 25.1 25.5 26.3 26.1 25.8 26.2 25.5 Vinyl (wt%) 37.8 38.5 38.1 37.8 38.1 38.6 38.4 Mooney viscosity
(ML(1+4) @ 100℃) Second reactant 56.3 54.0 67.4 68.0 68.0 49.6 54.8 Third reactant 60.3 63.7 72.2 67.5 68.1 62.1 64.1 Final copolymer 64.7 68.9 74.7 68.3 72.8 66.3 76.4 Mooney viscosity stability Mooney viscosity
(After heat aging) 70.2 71.9 80.5 70.8 78.0 81.3 100.6 Mooney viscosity tea 5.5 3.0 5.8 2.5 5.2 15.0 24.2 Molecular weight characteristics Number average molecular weight (Mn, X10 ⁵ , g/mol) 1.63 1.85 1.94 1.73 1.77 - - Weight average molecular weight (Mw, X10 ⁵ , g/mol) 4.38 5.25 5.45 4.81 4.97 - - Molecular weight distribution (Mw/Mn) 2.69 2.84 2.81 2.78 2.81 - -

As shown in Table 1, the modified styrene-butadiene copolymers of Examples 1 to 3 according to an embodiment of the present invention have a Mooney viscosity as the second reactant (before the denaturation reaction), and the third reactant (after the first denaturation reaction). ) And the final copolymer (after the second modification reaction), but in the case of the styrene-butadiene copolymer of Comparative Example 1 in which the modification reaction was not performed, the Mooney viscosity in the second reactant and the final copolymer Even in the case of the modified styrene-butadiene copolymer of Comparative Example 2 in which the Mooney viscosity was equal and only the first modification reaction was performed, the second and third reactants exhibited equivalent Mooney viscosity, and there was a difference in Mooney viscosity only between the final copolymer and the third reactant. Indicated. As a result of the above, the modified styrene-butadiene copolymer prepared in Examples 1 to 3 prepared through the production method according to an embodiment of the present invention was subjected to a modification reaction in the intermediate chain of the polymer chain by primary modification ( This means that the coupling reaction) was performed, and then the terminal denaturation reaction was performed by secondary denaturation.

Meanwhile, in the case of the modified styrene-butadiene copolymers of Comparative Examples 3 and 4, the Mooney viscosity was the second reactant (before the modification reaction), the third reactant (after the first modification reaction), and the final copolymer (after the second modification reaction). It was confirmed that the primary and secondary denaturation was performed by showing an increasing form as the temperature increased. The viscosity) was as small as 10 or less, whereas the modified styrene-butadiene copolymers of Comparative Example 3 and Comparative Example 4 showed a large difference of 15 and 24.2, respectively. This is a modified styrene-butadiene copolymer prepared through the use of a material having two alkoxy groups bonded to silica as a modifier during the first reaction and the second reaction in the production method according to an embodiment of the present invention. The Mooney viscosity of is also a result indicating that stability can be excellent.

Experimental Example 2

In order to compare and analyze the physical properties of the rubber compositions including the respective copolymers of Examples 1 to 3 and Comparative Examples 1 and 2, and molded articles manufactured therefrom, Mooney viscosity, modification rate, vulcanization characteristics, and viscoelastic characteristics And tensile strength was measured. The results are shown in Table 3 below. On the other hand, in the case of the copolymers of Comparative Example 3 and Comparative Example 4, Mooney viscosity stability was significantly deteriorated, and was excluded from the measurement of the properties of the blend properties.

1) Preparation of crosslinked rubber

Each crosslinked rubber was prepared through the first stage kneading process and the second stage kneading process, and the materials used in the first stage kneading process and the second stage kneading process are shown in Table 2 below. At this time, the amount of materials excluding the copolymer is shown based on 100 parts by weight of the copolymer.

In the first stage kneading, a half-bar remixer attached with a temperature control device is used, and each of the above copolymers, first filler, second filler, process oil, anti-aging agent, zinc oxide (ZnO), stearic acid. ), wax and antioxidant were mixed and kneaded in the first stage. At this time, the first stage kneading was carried out by increasing the number of rotations of the rotor to raise the internal temperature to 150°C and maintaining the temperature for 5 minutes to obtain a first blend. In the second-stage kneading, after cooling the first blend to room temperature, a rubber accelerator, sulfur powder, and vulcanization accelerator are added to the kneader, and the sheet is gently mixed at 50 rpm for 1.5 minutes at 50°C. A second formulation was obtained which was a rubber in the form of. Thereafter, heat was applied to each of the second formulations at a 160° C. press for a time multiplied by 1.3 times t'90 hours to prepare each crosslinked rubber.

division Substance name Parts by weight 1st stage kneading Rubber Each copolymer 100 First filler Silica (7000 GR, Degussa) 50 parts by weight + Carbon Black (High Abrasion Furnace) 20 parts by weight) 70 Process oil TDAE 37.5 Silane coupling agent X50S(Degussa)
(50 wt% carbon black + 50 wt% bis(3-triethoxysilylpropyltetrasulfane)) 11.2 Stearic acid Stearic acid 2.0 Zinc oxide Zinc oxide 3.0 Anti-aging agent RD (Flexsys)
(Polymerized 2,2,4-trimethyl-1,2-dihydroquinoline) 2.0 Antioxidant 6PPD (Flexsys)
(N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine) 2.0 Wax Wax 1.0 2nd stage kneading Rubber accelerator DPG (Flexsys)
(Diphenylguanidine) 1.75 Sulfur powder sulfur 1.5 Vulcanization accelerator CZ (Flexsys)
(Nt-butyl-2-benzothiazylsulfonamide) 2.0

2) Mooney viscosity

Mooney viscosity was measured using each of the second formulations prepared during preparation of the crosslinked rubber specimen. Specifically, MV-2000E (Monsanto) was used to measure a rotor speed of 2±0.02 rpm, and a large rotor was used to measure ML(1+4) at 100°C. At this time, the sample was left at room temperature (23±3℃) for at least 30 minutes, then 27±3 g was collected, filled in the die cavity, and measured by operating the platen.

3) denaturation rate

Using each of the second formulations, the amount of rubber bound to the filler was calculated from the amount of the component remaining undissolved in toluene by the bound rubber measurement method, and the ratio of the rubber bound to the filler to the amount of rubber in the second formulation was obtained. The value was used as the rate of denaturation. At this time, the denaturation rate was expressed as an index (percentage, %) using the value of Comparative Example 1 as 100. ^{Specifically, a 1 cm 3} volume hexagonal cube box was made with a 100 mesh stainless steel net, _{and the weight (W 0} ) was measured to 3 decimal places. After uniformly slicing 1 g of each second formulation into 1 mm × 1 mm × 1 mm size, _{measuring the weight (W 1} ) to 3 decimal places, putting it in the box and covering the lid, 2 L filled with 1000 cc of toluene Dipped in a glass bottle of. At this time, the box was placed so as to be placed in the middle of the toluene solution. After 24 hours, the box was taken out and dried in a vacuum oven at 140° C. for 35 minutes, and the weight (W ₂ ) was measured. Thereafter, the denaturation rate was calculated through Equation 2 below.

[Equation 2]

Denaturation rate (%)=[(W ₃ -W ₅ )/W ₄ ]×100

In Equation 2, W ₃ is W ₂ -W ₀ , W ₄ is the theoretical amount of rubber (the amount of rubber in 1 g of the second compound), and W ₅ is the amount of the theoretical inorganic substance (the amount of filler in 1 g of the second compound)

4) Curing characteristics

Vulcanization properties were measured using each of the first formulations prepared during the preparation of the crosslinked rubber specimen, specifically MDR 2000E (moving die rheometer, Monsanto) at 160° C. for 30 minutes, 1°, Arc, 1.7 Tc'90 (90% curing time) was measured in Hz conditions.

5) Tensile characteristics

For tensile properties, each test piece was prepared according to the tensile test method of ASTM 412, and the tensile strength at the time of cutting and the tensile stress at the time of 300% elongation (300% modulus) were measured. Specifically, tensile properties were measured at a rate of 50 cm/min at room temperature using a Universal Test Machin 4204 (Instron) tensile tester to obtain tensile strength and tensile stress values at 300% elongation. At this time, each result value was expressed as an index (percentage, %) using the value of Comparative Example 1 as 100.

6) wear resistance

Abrasion resistance was measured using DIN Abrader at 40 rpm for the drum rotation speed of the wear machine and 4.2 mm per revolution for the lateral movement speed of the drum. At this time, the abrasive paper used was Aluminum Oxide Grain 60, and the average value was used by measuring three samples for each crosslinked rubber, and the volume reduction was obtained by dividing the weight loss by the specific gravity and used as the wear value. Each result value was expressed as an index (percentage, %) using the value of Comparative Example 1 as 100.

7) Viscoelastic properties

The running resistance (Rolling ResisTance, 60°C Tan δ) of each of the prepared crosslinked rubbers was measured.

Specifically, using Explexor 500N (Gabo, Germany) was measured in a temperature sweep mode while heating at 2/min at each measurement temperature (20~70℃) at Frequency 10 Hz, Static Strain 3.5%, and Dynamic Strain 3%. . At this time, the value of 60 Tan δ is a measure of driving resistance, and the lower the value is, the less hysteresis loss is and indicates that the driving resistance (fuel economy) is excellent. Each result value was expressed as an index (percentage, %) using the value of Comparative Example 1 as 100.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Mooney viscosity 2nd formulation 54.9 53.7 82.5 86.1 97.4 △ Mooney viscosity -9.8 -15.2 +7.8 +17.8 +24.6 Modification rate (bound rubber) 137 135 133 100 128 Crosslinking properties Tc'90(min) 16.44 15.91 15.82 17.57 16.28 Tensile properties 300% modulus (Index, %) 110 114 107 100 103 Wear resistance DIN wear
(Index, %) 105 107 108 100 104 Viscoelasticity Tan δ at 60
(Index, %) 117 115 112 100 112 * △ Mooney viscosity: Mooney viscosity of the second formulation-Mooney viscosity of the final copolymer (see Table 1)

As shown in Table 3, the Mooney viscosity of the second blend prepared using the modified styrene-butadiene copolymer of Examples 1 to 3 according to an embodiment of the present invention was Compared to the second blend, it shows a significantly smaller value and shows the difference in the Mooney viscosity between the second blend and the final copolymer.Examples 1 to 3 also have a Mooney viscosity value in the range of 10 to -30, i.e., modified styrene-butadiene copolymer. It was confirmed that even if the Mooney viscosity of the second formulation containing the filler was reduced or increased compared to the Mooney viscosity of the modified styrene-butadiene copolymer itself, it did not increase significantly and showed an appropriate range. Here, the lower the Mooney viscosity value of the blend, the better the flowability can be, and as a result, the better the processability.

This indicates that the modified styrene-butadiene copolymers of Examples 1 to 3 prepared according to an exemplary embodiment of the present invention have excellent affinity with a filler, and are thus easily blended.

In addition, the modified styrene-butadiene copolymers of Examples 1 to 3 prepared through the manufacturing method according to an embodiment of the present invention were compared with the unmodified or terminally modified styrene-butadiene copolymers of Comparative Examples 1 and 2 Thus, it was confirmed that the modification rate was remarkably high, and all of the tensile properties, abrasion resistance, and viscoelastic properties were remarkably improved.

On the other hand, through the measured value of the difference in Mooney viscosity, which is a measure of processability, it was confirmed that the degree of improvement in processability varies depending on the molar ratio of the polyfunctional anionic polymerization initiator and the primary modifying agent when preparing the modified styrene-butadiene copolymer. Specifically, in Examples 1 to 3, the polyfunctional anionic polymerization initiator to the first denaturant were used in a 1:0.25 molar ratio, 1:0.5 molar ratio, and 1:1 molar ratio, respectively, and the resulting Mooney viscosity difference was -9.8,- 15.2 and +7.8, through which the multifunctional anionic polymerization initiator to the first denaturant was used in a molar ratio of 1:0.25 and 1:0.5 rather than using a molar ratio of 1:1, it was more excellent in processability. It was confirmed that the effect can be achieved.

Claims (19)

1) polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in the presence of a polyfunctional anionic polymerization initiator in a hydrocarbon solvent to prepare an active polymer in which alkali metals are bonded to both ends;
2) first reacting the polymer with a first denaturant; And
3) comprising the step of secondary reaction with a second denaturant after the first reaction,
A method for producing a modified conjugated diene-based polymer wherein the first and second denaturing agents are independently of each other a compound represented by the following formula (1):
[Formula 1]

In Formula 1,
R ₁ and R ₂ are each independently an alkyl group having 1 to 6 carbon atoms; Or they are connected to each other to form an aliphatic cyclic hydrocarbon group having 3 to 6 carbon atoms,
When R ₁ and R ₂ form an aliphatic cyclic hydrocarbon group, at least one C 1 to C 3 alkyl group is substituted,
R ₃ is an alkyl group having 1 to 6 carbon atoms,
R ₄ is an alkylene group having 1 to 10 carbon atoms,
R ₅ and R ₆ are each independently an alkyl group having 1 to 6 carbon atoms.
delete delete delete The method according to claim 1,
The compound represented by Formula 1 is 3-(diethoxy(methyl)silyl)-N,N-diethylpropan-2-amine or 2-(N,N-dimethylaminopropyl)-2,5,5-trimethyl -1,3,2-dioxacillinan is a method for producing a modified conjugated diene-based polymer.
The method according to claim 1,
The first modifier is a method for producing a modified conjugated diene-based polymer to be used in an amount of 0.1 mol to 1.0 mol relative to 1 mol of the polyfunctional anionic polymerization initiator.
The method according to claim 1,
The method of manufacturing a modified conjugated diene-based polymer, wherein the first and second modifiers are the same material.
The method according to claim 1,
The method for producing a modified conjugated diene-based polymer is used in an amount of 1.0 to 10.0 moles relative to 1 mole of the first denaturing agent.
The method according to claim 1,
The method for producing a modified conjugated diene-based polymer wherein the polyfunctional anionic polymerization initiator is prepared by reacting an aromatic compound and an organolithium compound in a hydrocarbon solvent.
The method of claim 9,
The method for producing a modified conjugated diene-based polymer wherein the aromatic compound and the organolithium compound are reacted in a molar ratio of 1:1 to 1:2.
The method of claim 9,
The aromatic compound is o-diisopropenyl benzene, m-diisopropenyl benzene, p-diisopropenyl benzene, o-divinyl benzene, m-divinyl benzene, p-divinyl benzene, 1,2, 4-trivinylbenzene, 1,2-vinyl-3,4-dimethylbenzene, 1,3-divinyl naphthalene, 1,3,5-trivinylnaphthalene, 2,4-divinylbiphenyl, 3,5, Modified conjugation of at least one selected from the group consisting of 4'-trivinyl biphenyl, 1,2-divinyl-3,4-dimethylbenzene and 1,5,6-trivinyl-3,7-diethyl naphthalene Method for producing a diene-based polymer.
The method of claim 9,
The organolithium compound is one or more selected from the group consisting of ethyl lithium, propyl lithium, n-butyl lithium, s-butyl lithium, t-butyl lithium, hexyl lithium, phenyl lithium, lithium dimethyl amide and lithium isopropyl amide. Method for producing a modified conjugated diene-based polymer.
The method according to claim 1,
The method for producing a modified conjugated diene-based polymer, wherein the polyfunctional anionic polymerization initiator is used in an amount of 0.1 mmol to 5.0 mmol based on a total of 100 g of monomers.
The method according to claim 1,
The polymerization of step 1) is a method for producing a modified conjugated diene-based polymer to be performed by further adding a polar additive.
The method of claim 14,
The method for producing a modified conjugated diene-based polymer is added in an amount of 0.01 g to 2.0 g based on a total of 100 g of the polar additive.
Two or more conjugated diene-based polymer-derived units are bonded or coupled by a functional group derived from the first denaturant,
The two or more conjugated diene-based polymer-derived units each contain a functional group derived from a second denaturant at the other end,
A modified conjugated diene-based polymer prepared from the production method according to claim 1, wherein the first and second denaturing agents are independently of each other a compound represented by the following formula (1):
[Formula 1]

In Formula 1,
R ₁ and R ₂ are each independently an alkyl group having 1 to 6 carbon atoms; Or they are connected to each other to form an aliphatic cyclic hydrocarbon group having 3 to 6 carbon atoms,
When R ₁ and R ₂ form an aliphatic cyclic hydrocarbon group, at least one C 1 to C 3 alkyl group is substituted,
R ₃ is an alkyl group having 1 to 6 carbon atoms,
R ₄ is an alkylene group having 1 to 10 carbon atoms,
R ₅ and R ₆ are each independently an alkyl group having 1 to 6 carbon atoms.
The method of claim 16,
The polymer is a modified conjugated diene-based polymer containing 0.05 mmol to 5.0 mmol of an amine group per 100 g of the polymer.
The method of claim 16,
The polymer is a modified conjugated diene-based polymer containing 0.2 mmol to 20.0 mmol of a siloxane group per 100 g of the polymer.
The method of claim 16,
The polymer is a modified conjugated diene-based polymer having a Mooney viscosity difference (Δ MV) represented by the following equation (1) of 10 to -30:
[Equation 1]
△ MV = CMV-PMV
In Equation 1, CMV is the Mooney viscosity of a blend containing a modified conjugated diene-based polymer, a filler, and a crosslinking agent, and PMV is the Mooney viscosity of the modified conjugated diene-based polymer.