KR102024139B1 - Modifying agent, preparation method of modified conjugated diene polymer using the modifying agent and modified conjugated diene polymer - Google Patents

Abstract

The present invention relates to a rubber modifier, a rubber modifier, a modified conjugated diene-based polymer comprising a functional group thereof, a method for preparing the modified conjugated diene-based polymer, a rubber composition comprising the modified conjugated diene-based polymer, and a tire made from the rubber composition. It is about. Accordingly, the rubber modifier compound may be used as a modifier for rubber, in particular, a conjugated diene-based polymer, to be bonded to the conjugated diene-based polymer chain to easily introduce a filler affinity functional group. Therefore, the modified conjugated diene-based polymer prepared by using the rubber modifier rubber modifier may contain a plurality of functional groups.

Description

Modifying agent, preparation method of modified conjugated diene polymer using the modifying agent and modified conjugated diene polymer

The present invention relates to a rubber modifier, a method for producing a modified conjugated diene-based polymer using the same, a modified conjugated diene-based polymer prepared from the production method, a rubber composition comprising the modified conjugated diene-based polymer, and a tire made from the rubber composition will be.

In recent years, with the demand for low fuel consumption for automobiles, there has been a demand for conjugated diene-based polymers having low rolling resistance, excellent wear resistance and tensile properties, and adjusting stability represented by wet skid resistance.

In order to reduce the rolling 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, a repulsive elasticity of 50 ° C. to 80 ° C., tan δ, Goodrich heating and the like are used. That is, a rubber material having a high rebound elasticity at the above temperature or a small tan δ or good rich heat generation is preferable.

As a rubber material having a low hysteresis loss, natural rubber, polyisoprene rubber, polybutadiene rubber and the like are known, but these have a problem of low wet skid resistance. Recently, conjugated diene-based (co) polymers such as styrene-butadiene rubber (hereinafter referred to as SBR) or butadiene rubber (hereinafter referred to as BR) have been produced by emulsion polymerization or solution polymerization and used as rubber for tires. . Among them, the greatest advantage of solution polymerization over emulsion polymerization is that the vinyl structure content and styrene content that define rubber properties can be arbitrarily controlled, and molecular weight and physical properties can be adjusted by coupling or modification. It can be adjusted. Therefore, it is easy to change the structure of the final manufactured SBR or BR rubber, and the movement of the chain ends can be reduced by the binding or modification of the chain ends, and the bonding strength with fillers such as silica or carbon black can be increased. It is widely used as a rubber material for tires.

When the solution-polymerized SBR is used as a rubber material for tires, the vinyl content in the SBR is increased to increase the glass transition temperature of the rubber, thereby controlling tire required properties such as running resistance and braking force, and properly adjusting the glass transition temperature. By adjusting the fuel consumption can be reduced.

The solution polymerization SBR is prepared using an anionic polymerization initiator, and is used by binding or modifying the chain ends of the formed polymer using various modifiers.

For example, US Pat. No. 4,397,994 discloses a technique in which the active anion at the chain end of a polymer obtained by polymerizing styrene-butadiene in a nonpolar solvent using alkyllithium, a monofunctional initiator, using a binder such as a tin compound. It was.

Meanwhile, carbon black and silica are used as reinforcing fillers for tire treads. When silica is used as reinforcing fillers, low hysteresis loss and wet skid resistance are improved. However, the hydrophilic surface silica has a disadvantage of poor dispersibility due to low affinity with rubber compared to the hydrophobic surface carbon black, so that a separate silane coupler may be used to improve dispersibility or to impart a bond between silica and rubber. It is necessary to use a ring agent.

Thus, a method of introducing a functional group having affinity or reactivity with silica to the rubber molecule terminal portion, but the effect is not sufficient.

Therefore, there is a need for development of a rubber having high affinity with fillers including silica.

US 4,397,994 A

The present invention has been made to solve the problems of the prior art, and an object thereof is to provide a rubber modifier capable of providing an amine functional group.

Another object of the present invention is to provide a method for producing a modified conjugated diene-based polymer using the rubber modifier.

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

In addition, another object of the present invention to provide a rubber composition comprising the modified conjugated diene-based polymer.

Furthermore, another object of the present invention is to provide a tire made from the rubber composition.

In order to solve the above problems, there is provided a rubber modifier represented by the following formula (1).

[Formula 1]

In Chemical Formula 1,

n, m and o are each independently an integer from 0 to 20.

In addition, the present invention is to prepare an active polymer in which the alkali metal is bonded to at least one end by polymerizing a conjugated diene monomer or an aromatic vinyl monomer and a conjugated diene monomer in the presence of an organic alkali metal compound in a hydrocarbon solvent (step 1 ); And it provides a method for producing a modified conjugated diene-based polymer comprising the step (step 2) of reacting the active polymer with the rubber modifier represented by the formula (1).

In addition, there is provided a modified conjugated diene-based polymer prepared by the above production method.

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

Furthermore, there is provided a tire made from the rubber composition.

The rubber modifier represented by Formula 1 according to the present invention may be used as a modifier for rubber, particularly a conjugated diene-based polymer, and may be bonded to the conjugated diene-based polymer chain to provide a functional functional group such as an amine group.

The production method according to the present invention can easily prepare a modified conjugated diene-based polymer having excellent modification rate by using a rubber modifier represented by the formula (1).

In addition, the modified conjugated diene-based polymer according to the present invention may be excellent in affinity with the filler, in particular, silica-based filler by binding the functional group, such as amine group derived from the rubber modifier represented by the formula (1) in the polymer chain.

In addition, the rubber composition according to the present invention may be excellent in workability by including a modified conjugated diene-based polymer having excellent affinity with the filler, and as a result, the processed product (for example, a tire) manufactured using the rubber composition may be tensile. Strength, wear resistance and low cloud resistance properties can be excellent.

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

The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

The present invention provides a rubber modifier capable of providing an amine function.

The rubber modifier according to an embodiment of the present invention is characterized by represented by the following formula (1).

[Formula 1]

In Chemical Formula 1,

n, m and o are each independently an integer from 0 to 20.

Specifically, in Formula 1, n, m, and o may be each independently an integer of 0 to 10.

In addition, in Formula 1, n, m, and o may be each independently an integer of 0 to 5.

More specifically, the rubber modifier represented by Formula 1 may be represented by the following Formula 2.

[Formula 2]

The rubber modifier according to an embodiment of the present invention contains a plurality of amines and has a vinyl group as shown in Formula 1, and when used as a modifier of a rubber modifier, such as a conjugated diene-based polymer, a plurality of amine groups are bonded. A modified conjugated diene-based polymer may be prepared, and a compounding affinity with the reinforcing agent of the modified conjugated diene-based polymer may be imparted thereto.

In addition, the rubber modifier represented by Formula 1 may be a modifier for a conjugated diene-based polymer. Herein, the conjugated diene polymer may be a conjugated diene monomer homopolymer or a copolymer of a conjugated diene monomer and an aromatic vinyl monomer.

In addition, the present invention provides a modified conjugated diene-based polymer represented by the following formula (3).

[Formula 3]

In Chemical Formula 3,

P is a conjugated diene polymer chain,

n, m and o are each independently an integer from 0 to 20.

The modified conjugated diene-based polymer according to an embodiment of the present invention may be a combination of a rubber modifier derived unit represented by the formula (1). That is, the modified conjugated diene-based polymer may be modified by a rubber modifier represented by the formula (1).

The modified conjugated diene-based polymer has an amine group and a vinyl group bonded to the polymer chain, it may be excellent in affinity with the filler, especially silica filler. Accordingly, the physical properties of the rubber composition including the modified conjugated diene-based polymer may be excellent, and consequently, the tensile strength of a molded article, such as a tire, manufactured using the rubber composition may be excellent. Abrasion resistance and wet road resistance can be improved.

In addition, 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.

The modified conjugated diene-based polymer may have a polydispersity index (PDI) of 0.5 to 10, specifically 0.5 to 5, and more specifically 1 to 2.

In addition, the modified conjugated diene-based polymer may have a vinyl content of 18 wt% or more, specifically 25 wt% or more, more specifically 30 wt% to 70 wt%, and the glass transition temperature when the vinyl content is in the above range. Can be adjusted up to an appropriate range, and when applied to a tire, not only the properties required for the tire such as driving resistance and braking force are excellent, but also it has an effect of reducing fuel consumption.

In this case, the vinyl content refers to the content of the monomer having a vinyl group or the content of the 1,2-added conjugated diene monomer rather than 1,4-addition based on 100% by weight of the conjugated diene monomer.

In addition, the present invention provides a method for producing a modified conjugated diene-based polymer using a rubber modifier represented by the formula (1).

The production method according to an embodiment of the present invention is an active polymer in which an alkali metal is bonded to at least one terminal by polymerizing a conjugated diene monomer or an aromatic vinyl monomer and a conjugated diene monomer in the presence of an organic alkali metal compound in a hydrocarbon solvent. Preparing (step 1); And reacting the active polymer with a rubber modifier represented by Chemical Formula 1 (step 2).

Step 1 is a step for preparing an active polymer having an alkali metal bonded to at least one end thereof, which is performed by polymerizing a conjugated diene monomer or an aromatic vinyl monomer and a conjugated diene monomer in the presence of an organic alkali metal compound in a hydrocarbon solvent. Can be.

The polymerization of step 1 may be to use a conjugated diene monomer alone or a conjugated diene monomer and an aromatic vinyl monomer together as a monomer. That is, the polymer prepared by the above production method according to an embodiment of the present invention may be a conjugated diene monomer homopolymer or a copolymer derived from a conjugated diene monomer and an aromatic vinyl monomer.

In this case, when the polymer is a copolymer derived from a conjugated diene monomer and an aromatic vinyl monomer, the copolymer may be a random copolymer.

Here, the "random copolymer" may indicate that the structural units constituting the copolymer are randomly arranged.

The conjugated diene 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.

When the conjugated diene monomer and the aromatic vinyl monomer are used together as the monomer, the conjugated diene monomer may include 60% by weight or more of the unit derived from the conjugated diene monomer in the finally prepared modified conjugated diene polymer. 60 wt% to 90 wt%, more specifically, 60 wt% to 85 wt%.

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

When the conjugated diene monomer and the aromatic vinyl monomer are used together as the monomer, the aromatic vinyl monomer may be 40 wt% or less of the aromatic vinyl monomer-derived unit in the finally prepared modified conjugated diene polymer. It may be used in an amount comprised from 10% by weight to 40% by weight, more specifically 15% by weight 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 organoalkali metal compound may be used in an amount of 0.01 mmol to 10 mmol based on 100 g of the total monomer.

 The organoalkali metal compound is not particularly limited, but for example, methyllithium, ethyllithium, propyllithium, n-butyllithium, s-butyllithium, t-butyllithium, hexyllithium, n-decyllithium, t-octylithium, Phenyllithium, 1-naphthyllithium, n-eicosilium, 4-butylphenyllithium, 4-tolyllithium, cyclohexyllithium, 3,5-di-n-heptylcyclohexyllithium, 4-cyclopentyllithium, naph At least one member selected from the group consisting of sodium sodium, naphthyl potassium, lithium alkoxide, sodium alkoxide, potassium alkoxide, lithium sulfonate, sodium sulfonate, potassium sulfonate, lithium amide, sodium amide, potassium amide, lithium isopropylamide Can be.

The polymerization of step 1 may be performed by further adding a polar additive as needed, the polar additive may be added to 0.001 parts by weight to 10 parts by weight based on 100 parts by weight of the total monomer. Specifically, the amount may be added in an amount of 0.001 part by weight to 1 part by weight, more specifically 0.005 part by weight to 0.1 part by weight, based on 100 parts by weight of the total monomers.

The polar additives include tetrahydrofuran, ditetrahydrofurylpropane, diethyl ether, cycloamal ether, dipropyl ether, ethylene dimethyl ether, ethylene dimethyl ether, diethyl 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.

In the manufacturing method according to an embodiment of the present invention, when the conjugated diene-based monomer and the aromatic vinyl-based monomer are copolymerized by using the polar additive, the reaction rate can be easily compensated for by forming a random copolymer. Can be induced.

The polymerization of step 1 may be carried out through adiabatic polymerization, or isothermal polymerization.

Here, adiabatic polymerization refers to a polymerization method including a step of polymerizing with self-heating reaction without adding heat after the addition of the organoalkali metal compound, and the isothermal polymerization is an arbitrary heat after adding the organoalkali metal compound. It represents a polymerization method for maintaining a constant temperature of the polymer by adding or taking away heat.

The polymerization may be performed at a temperature range of -20 ° C to 200 ° C, specifically 0 ° C to 150 ° C, and more specifically 10 ° C to 120 ° C.

Step 2 is a modification reaction step of reacting the active polymer with a rubber modifier represented by Formula 1 to prepare a modified conjugated diene-based polymer.

In this case, the rubber modifier represented by Chemical Formula 1 may be as described above.

The compound represented by Chemical Formula 1 may be used in a ratio of 0.1 mole to 10 moles relative to 1 mole of the organic alkali metal compound. The reaction of Step 2 according to an embodiment of the present invention may be performed to introduce a functional group into a polymer. As a modification reaction, each reaction may be performed for 1 minute to 5 hours at a temperature range of 0 ℃ to 90 ℃.

The preparation method according to an embodiment of the present invention may further include one or more steps of recovering and drying the solvent and the unreacted monomer, if necessary after step 2 above.

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

The rubber composition according to an embodiment of the present invention may be a modified conjugated diene-based polymer containing 10 wt% or more, specifically 10 wt% to 100 wt%, more specifically 20 wt% to 90 wt%. have. If the content of the modified conjugated diene-based polymer is less than 10% by weight, the effect of improving the wear resistance and crack resistance of a molded article, for example, a tire manufactured using the rubber composition may be insignificant.

In addition, the rubber composition may further include other rubber components, if necessary, in addition to the modified conjugated diene-based polymer, wherein the rubber components may be included in an amount of 90% by weight or less based on the total weight of the rubber composition. Specifically, the modified conjugated diene copolymer may be included in an amount of 1 part by weight to 900 parts by weight based on 100 parts by weight.

The rubber component may be natural rubber or synthetic rubber, for example, the rubber component may include natural rubber (NR) including cis-1,4-polyisoprene; Modified natural rubbers such as epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber obtained by modifying or refining the general natural rubber; Styrene-butadiene copolymer (SBR), polybutadiene (BR), polyisoprene (IR), butyl rubber (IIR), ethylene-propylene copolymer, polyisobutylene-co-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., and any one or a mixture of two or more thereof may be used. have.

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

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

Specific examples of the silane coupling agent 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-dimethylthiocarbamoyl tetrasul Feed, 3-triethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilyl Propylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzolyl tetrasulfide, 3-triethoxysilylpropyl methacrylate Monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide or dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide, and the like, and any one or a mixture of two or more thereof may be used. More specifically, in consideration of the reinforcing improvement effect, the silane coupling agent may be bis (3-triethoxysilylpropyl) polysulfide or 3-trimethoxysilylpropylbenzothiazyl tetrasulfide.

In the rubber composition according to one embodiment of the present invention, a modified conjugated diene-based polymer having a functional group having high affinity with a silica-based filler as an active moiety is used as the rubber component. The compounding amount can be reduced than usual. 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 silica-based filler. When used in the above range, the 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 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 parts by weight to 10 parts by weight based on 100 parts by weight of the rubber component. When included in the content range, it is possible to ensure the required elastic modulus and strength of the vulcanized rubber composition, and at the same time obtain a low fuel consumption.

In addition, the rubber composition according to an embodiment of the present invention, in addition to the components described above, various additives commonly used in the rubber industry, specifically, vulcanization accelerators, process oils, plasticizers, anti-aging agents, anti-scoring agents, zinc white (zinc white) ), Stearic acid, a thermosetting resin, or a thermoplastic resin may be further included.

The said vulcanization accelerator is not specifically limited, Specifically, M (2-mercapto benzothiazole), DM (dibenzothiazyl disulfide), CZ (N-cyclohexyl-2- benzothiazyl sulfenamide), etc. Thiazole compounds, or guanidine compounds such as DPG (diphenylguanidine) can be used. The vulcanization accelerator may be included in an amount of 0.1 parts by weight to 5 parts by weight based on 100 parts by weight of the rubber component.

In addition, the process oil acts as a softener in the rubber composition, specifically, may be a paraffinic, naphthenic, or aromatic compound, and more specifically, aromatic process oil, hysteresis loss in consideration of tensile strength and wear resistance. And naphthenic or paraffinic process oils may be used when considering low temperature properties. The process oil may be included in an amount of 100 parts by weight or less with respect to 100 parts by weight of the rubber component, when included in the content, it is possible to prevent the degradation of tensile strength, 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- Methoxy-2,2,4-trimethyl-1,2-dihydroquinoline, or a high temperature condensate of diphenylamine and acetone. The anti-aging agent may be used in an amount of 0.1 parts by weight 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 kneading machine such as a Banbury mixer, a roll, an internal mixer, etc. by the above formulation, and also has low heat resistance and abrasion resistance by a vulcanization process after molding. This excellent rubber composition can be obtained.

Accordingly, the rubber composition may be used for tire members such as tire treads, under treads, sidewalls, carcass coated rubbers, belt coated rubbers, bead fillers, pancreapers, or bead coated rubbers, dustproof rubbers, belt conveyors, hoses, and the like. It may be useful for the production of various industrial rubber products.

In addition, the present invention provides a tire manufactured using the rubber composition.

The tire may include a tire or a tire tread.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. However, the following Examples and Experimental Examples are provided to illustrate the present invention, and the scope of the present invention is not limited only to these examples.

Example

Into a 20 L autoclave reactor, 270 g of styrene, 710 g of 1,3 butadiene, 5000 g of normal hexane, and 1.3 g of 2,2-bis (2-oxoranyl) propane were added as a polar additive, and the temperature inside the reactor was increased to 40 ° C. Adjusted. When the internal temperature of the reactor reached 40 ° C, 4 mmol of n-butyllithium was added to the reactor to perform an adiabatic heating reaction. After 20 minutes of reaction, 20 g of 1,3-butadiene was added thereto, and the end of the SSBR was capped with butadiene. After 5 minutes, 12 mmol of the compound of Formula 2 was added and reacted for 15 minutes. Then, the polymerization reaction was stopped using ethanol, and 5 ml of a solution in which 0.3 wt% of BHT (butylated hydroxytoluene), an antioxidant, was dissolved in hexane was added. The resulting polymer was placed in hot water heated with steam, stirred to remove the solvent, and then dried in rolls to remove residual solvent and water to prepare a modified styrene-butadiene copolymer.

Comparative example

A commercially available commercial styrene-butadiene copolymer (5025-2HM grade, LANXESS) was used for the experiment.

Experimental Example

Tensile and viscoelastic properties were measured in order to compare and analyze the physical properties of the rubber composition and each of the molded articles prepared therefrom including the copolymers of Examples and Comparative Examples. The results are shown in Table 1 below.

1) Preparation of Rubber Composition

Each rubber composition was prepared through a first stage kneading, a second stage kneading and a third stage kneading. At this time, the amount of the substance except the modified conjugated diene copolymer is shown based on 100 parts by weight of the modified conjugated diene copolymer. In the first stage kneading, 100 parts by weight of each copolymer, 70 parts by weight of silica, and bis (3-triethoxysilylpropyl) tetrasulfate as a silane coupling agent were used at 80 rpm using a half-barrier with temperature controller. 11.02 parts by weight of feed, 33.75 parts by weight of process oil (TDAE), 2.0 parts by weight of antioxidant (TMDQ), 2.0 parts by weight of antioxidant, 3.0 parts by weight of zinc oxide (ZnO), 2.0 parts by weight of stearic acid, and 1.0 weight part of waxes were blended and kneaded. At this time, the temperature of the kneader was controlled and the primary blend was obtained at the discharge temperature of 140 ° C to 150 ° C. In the second stage kneading, after cooling the primary blend to room temperature, 1.75 parts by weight of a rubber accelerator (CZ), 1.5 parts by weight of sulfur powder, and 2.0 parts by weight of vulcanization accelerator are added to the kneader, and the mixture is mixed at a temperature of 60 ° C. or lower to mix the secondary mixture. Got. Thereafter, the second blend was molded in a third stage kneading, and vulcanized by vulcanization press at 180 to 90 minutes for each vulcanized rubber.

2) tensile properties

Tensile properties were prepared in accordance with the tensile test method of ASTM 412 (thickness 25 mm, length 80 mm) and measured the tensile strength at the time of cutting the specimen and the tensile stress (300% modulus) at 300% elongation. Specifically, tensile properties were measured at a rate of 50 cm / min at room temperature using a Universal Test Machin 4204 (Instron Co., Ltd.) tensile tester to obtain tensile strength and tensile stress at 300% elongation.

3) viscoelastic properties

Viscoelastic properties were measured by using a dynamic mechanical analyzer (TA Co., Ltd.) in a torsion mode by changing the strain at a frequency of 10 Hz and measuring temperature (0 ° C. to 60 ° C.). The Payne effect (ΔG ′) is expressed as the difference between the minimum and maximum values at 0.28% to 40% of the strain. The smaller the Payne effect, the better the dispersibility of the filler. In addition, the lower the high temperature 60 ° C Tan δ, the less the hysteresis loss and the better the low cloud resistance (fuel efficiency).

division Example Comparative example Tensile Properties Tensile strength (kgf / cm ² ) 176 174 300% tensile stress (kgf / cm ² ) 103 96 Viscoelastic Tan δ at 60 ℃ (Index) 105 100 △ G 'at 60 ℃ 0.65 0.76

As shown in Table 1, the rubber composition comprising the copolymer of the comparative example of the tensile properties and viscoelasticity of the rubber composition comprising the modified styrene-butadiene copolymer of the embodiment prepared using the modifier according to an embodiment of the present invention It was confirmed that the contrast is excellent.

Specifically, the rubber composition comprising the modified styrene-butadiene copolymer of the example prepared using the modifier according to the embodiment of the present invention is 60 ℃ compared to the rubber composition comprising the styrene-butadiene copolymer of the non-modified example It was confirmed that the Tan δ value at increased. This is a result showing that the modified styrene-butadiene copolymer prepared using the modifier according to the embodiment of the present invention may have excellent rolling resistance characteristics and high fuel efficiency.

In addition, the rubber composition comprising the modified styrene-butadiene copolymer of the example prepared using the modifying agent according to the embodiment of the present invention is ΔG 'compared to the rubber composition comprising the styrene-butadiene copolymer of the comparative example which is not modified. It was confirmed that is significantly low. This is a result indicating that the rubber composition including the modified styrene-butadiene copolymer according to the embodiment of the present invention may have excellent silica dispersibility.

Claims (22)

delete delete delete delete delete delete delete delete delete delete 1) preparing an active polymer in which an alkali metal is bound by polymerizing an aromatic vinyl monomer and a conjugated diene monomer in the presence of an organic alkali metal compound in a hydrocarbon solvent; And
2) A method of producing a modified conjugated diene-based polymer comprising the step of reacting the active polymer with a rubber modifier represented by the formula (1):
[Formula 1]

In Chemical Formula 1,
n, m and o are each independently an integer from 0 to 20.
The method according to claim 11,
The organoalkali metal compound is a method for producing a modified conjugated diene-based polymer that is used in 0.01 mmol to 10 mmol based on a total of 100 g of the monomer.
The method according to claim 11,
The organoalkali metal compound is methyllithium, ethyllithium, propyllithium, n-butyllithium, s-butyllithium, t-butyllithium, hexyllithium, n-decyllithium, t-octylithium, phenyllithium, 1-naphthyl Lithium, n-eicosilium, 4-butylphenyllithium, 4-tolyllithium, cyclohexyllithium, 3,5-di-n-heptylcyclohexyllithium, 4-cyclopentyllithium, naphthyl sodium, naphthyl potassium, Of the modified conjugated diene-based polymer is one or more selected from the group consisting of lithium alkoxide, sodium alkoxide, potassium alkoxide, lithium sulfonate, sodium sulfonate, potassium sulfonate, lithium amide, sodium amide, potassium amide, lithium isopropylamide Manufacturing method.
The method according to claim 11,
The polymerization of step 1) is a method for producing a modified conjugated diene-based polymer further by adding a polar additive.
The method according to claim 11 or 14,
The polar additive is a method for producing a modified conjugated diene-based polymer is added in an amount of 0.001 to 10 parts by weight based on 100 parts by weight of the total monomer.
The method according to claim 11,
Formula 1 is a method for producing a modified conjugated diene polymer that is a compound represented by the formula (2):
[Formula 2]

The method according to claim 11,
The compound represented by Formula 1 is a method for producing a modified conjugated diene-based polymer that is used in a ratio of 0.1 to 10 moles relative to 1 mole of the organic alkali metal compound.
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