KR102165117B1 - Modified conjugated diene polymer and method for preparing the same - Google Patents

Abstract

상기 화학식 1에서, 각 치환기의 정의는 발명의 설명 상 정의된 바와 같다.The present invention relates to a modified conjugated diene-based polymer, and more particularly, a modified conjugated diene-based polymer comprising a repeating unit derived from a conjugated diene-based monomer, and a functional group derived from a denaturant including a compound represented by the following formula (1) at one end A polymer and a method for preparing the same are provided.
[Formula 1]

In Formula 1, the definition of each substituent is as defined in the description of the invention.

Description

Modified conjugated diene polymer and its manufacturing method {MODIFIED CONJUGATED DIENE POLYMER AND METHOD FOR PREPARING THE SAME}

The present invention relates to a modified conjugated diene-based polymer, and more specifically, a modified conjugated diene-based polymer having excellent processability, tensile strength, abrasion resistance, and wet road surface resistance by including a functional group derived from a modifying agent having excellent affinity with an inorganic filler. It relates to a polymer.

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

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, resilience of 50°C to 80°C, tan δ, Goodrich heat generation, and the like are used. That is, a rubber material having high repulsion elasticity at the above temperature or low tan δ and Goodrich heat generation is preferable.

As rubber materials having a low hysteresis loss, natural rubber, polyisoprene rubber, polybutadiene rubber, and the like are known, but these have a problem of low resistance to wet road surfaces. Accordingly, recently, conjugated diene-based polymers or copolymers such as styrene-butadiene rubber (hereinafter referred to as SBR) or butadiene rubber (hereinafter referred to as BR) have been manufactured by emulsion polymerization or solution polymerization and are 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 BR, reduce the movement of the chain ends by bonding or denaturation of the chain ends, and increase the bonding strength with a filler such as silica or carbon black, so that SBR by solution polymerization is It is widely used as a rubber material.

When such a solution polymerization SBR is used as a rubber material for a tire, the glass transition temperature of the rubber can be increased by increasing the vinyl content in the SBR, so that the required properties of the tire such as running resistance and braking force can be adjusted, as well as the glass transition temperature. Fuel consumption can be reduced by appropriate control. The solution polymerization SBR is prepared by 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 technology 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, and when silica is used as a reinforcing filler, low hysteresis loss and resistance to wet road surfaces are improved. However, silica on a hydrophilic surface compared to carbon black on a hydrophobic surface has a drawback of poor dispersibility due to low affinity with rubber, so a separate silane couple is used to improve dispersibility or to impart a silica-rubber bond. 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.

US 4397994 A

The present invention was devised to solve the problems of the prior art, and by including a functional group derived from a modifier having excellent affinity with an inorganic filler, it has excellent processability even with a high molecular weight, and has excellent tensile strength, abrasion resistance, and resistance to wet road surfaces. An object of the present invention is to provide an excellent modified conjugated diene-based polymer and a method for producing the same.

According to an embodiment of the present invention for solving the above problems, the present invention includes a conjugated diene-based monomer-derived repeating unit, and a denaturant-derived functional group comprising a compound represented by the following formula (1) at one end Conjugated diene-based polymers are provided:

[Formula 1]

In Formula 1, X ¹ and X ² are each independently CR ⁶ , an N atom, an O atom, or an S atom, but at least one of X ¹ and X ² may be an N atom, and X ¹ or X ² is In the case of an O atom or an S atom, R ⁴ or R ⁵ may not be present, R ¹ may be a divalent hydrocarbon group having 1 to 30 carbon atoms, and R ² and R ³ are each independently of 1 to 30 carbon atoms. It may be a monovalent hydrocarbon group, and R ⁴ and R ⁵ are each independently hydrogen, a monovalent hydrocarbon group having 1 to 30 carbon atoms, or a functional group represented by the following formula (2), but at least one of R ⁴ and R ⁵ must be represented by the following formula It may be a functional group represented by 2, and R ⁶ may be hydrogen or a monovalent hydrocarbon group having 1 to 30 carbon atoms,

[Formula 2]

In Formula 2, R ⁷ may be a divalent hydrocarbon group having 1 to 30 carbon atoms, and R ⁸ and R ⁹ are each independently hydrogen, a monovalent hydrocarbon group having 1 to 30 carbon atoms, or a monovalent hydrocarbon group having 1 to 30 carbon atoms It may be an unsubstituted, monosubstituted, disubstituted, or trisubstituted silyl group with a group.

In addition, the present invention comprises the steps of polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in a hydrocarbon solvent containing an organometallic compound to prepare an organic metal-bonded active polymer (S1); And it provides a method for producing a modified conjugated diene-based polymer comprising the step (S2) of reacting with a denaturing agent containing the active polymer and the compound represented by the following formula (1):

[Formula 1]

In Formula 1, the definition of each substituent is as defined above.

In addition, the present invention provides a denaturant comprising the compound represented by Formula 1 and a method for preparing the same.

In the case of denaturing a conjugated diene-based polymer from a modifier having excellent affinity with an inorganic filler according to the present invention, by including a functional group derived from the modifier at one end of the polymer, the modified conjugated diene-based polymer having excellent affinity with the inorganic filler It is possible to manufacture, and the modified conjugated diene-based polymer thus prepared has excellent processability even though it has a high molecular weight, and has excellent tensile strength, abrasion resistance, and resistance to wet road surfaces.

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

The terms or words used in the description and claims of the present invention should not be construed as being limited to their usual or dictionary meanings, and the inventors appropriately explain the concept of terms in order to explain their own invention in the best way. Based on the principle that it can be defined, it should be interpreted as a meaning and concept consistent with the technical idea of the present invention.

The modified conjugated diene-based polymer according to the present invention may contain a repeating unit derived from a conjugated diene-based monomer, and may include a functional group derived from a denaturant including a compound represented by the following formula (1) at one end:

[Formula 1]

In Formula 1, X ¹ and X ² are each independently CR ⁶ , an N atom, an O atom, or an S atom, but at least one of X ¹ and X ² may be an N atom, and X ¹ or X ² is In the case of an O atom or an S atom, R ⁴ or R ⁵ may not be present, R ¹ may be a divalent hydrocarbon group having 1 to 30 carbon atoms, and R ² and R ³ are each independently of 1 to 30 carbon atoms. It may be a monovalent hydrocarbon group, and R ⁴ and R ⁵ are each independently hydrogen, a monovalent hydrocarbon group having 1 to 30 carbon atoms, or a functional group represented by the following formula (2), but at least one of R ⁴ and R ⁵ must be represented by the following formula It may be a functional group represented by 2, and R ⁶ may be hydrogen or a monovalent hydrocarbon group having 1 to 30 carbon atoms,

[Formula 2]

In Formula 2, R ⁷ may be a divalent hydrocarbon group having 1 to 30 carbon atoms, and R ⁸ and R ⁹ are each independently hydrogen, a monovalent hydrocarbon group having 1 to 30 carbon atoms, or a monovalent hydrocarbon group having 1 to 30 carbon atoms It may be an unsubstituted, monosubstituted, disubstituted, or trisubstituted silyl group with a group.

As a specific example, in Formula 1, X ¹ and X ² are each independently CR ⁶ , or an N atom, but at least one of X ¹ and X ² may be an N atom, and R ¹ is 2 having 1 to 20 carbon atoms. May be a hydrocarbon group, R ² and R ³ may each independently be a monovalent hydrocarbon group having 1 to 20 carbon atoms, and R ⁴ and R ⁵ are each independently hydrogen, a monovalent hydrocarbon group having 1 to 20 carbon atoms, or the above A functional group represented by Formula 2, but at least one of R ⁴ and R ⁵ may be a functional group represented by Formula 2, and R ⁶ may be hydrogen or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and the formula 2 In, R ⁷ may be a divalent hydrocarbon group having 1 to 20 carbon atoms, and R ⁸ and R ⁹ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms, or an unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, 1 It may be a substituted, disubstituted, or trisubstituted silyl group.

In the present invention, the term'monovalent hydrocarbon group' means a monovalent atomic group in which carbon and hydrogen are bonded, such as a monovalent alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkyl group containing one or more unsaturated bonds, and an aryl group. In addition, the minimum number of carbon atoms of the substituent represented by the monovalent hydrocarbon may be determined according to the type of each substituent.

In the present invention, the term'divalent hydrocarbon group' refers to a divalent alkylene group, an alkenylene group, an alkynylene group, a cycloalkylene group, a cycloalkylene group containing one or more unsaturated bonds, and an arylene group. It may mean a valence group of atoms, and the minimum number of carbon atoms of a substituent represented by a divalent hydrocarbon may be determined according to the type of each substituent.

In the present invention, the term'unsubstituted silyl group' may refer to the silyl group itself represented by -SiH _3, and the'silyl group monosubstituted with a monovalent hydrocarbon group' means that one hydrogen of the silyl group is substituted with a monovalent hydrocarbon group. It may mean a silyl group, and'silyl group disubstituted with a monovalent hydrocarbon group'and'silyl group trisubstituted with a monovalent hydrocarbon group' are silyl in which two or three hydrogens of the silyl group are each substituted with a monovalent hydrocarbon group. It may mean a group, and when the silyl group is substituted with a plurality of monovalent hydrocarbon groups, that is, the monovalent hydrocarbon groups of the'disubstituted silyl group' and the'trisubstituted silyl group' may be the same or different from each other.

According to an embodiment of the present invention, the compound represented by Formula 1 may be a compound represented by Formula 1-1 below.

[Formula 1-1]

In Formula 1-1, Me is a methyl group, and Et is an ethyl group.

As described above, according to the present invention, when the conjugated diene-based polymer is modified from a modifier having excellent affinity with an inorganic filler, including the compound represented by Formula 1, by including a functional group derived from the modifier at one end of the polymer , It is possible to prepare a modified conjugated diene-based polymer having excellent affinity with inorganic fillers, and the modified conjugated diene-based polymer prepared in this way has excellent processability even though it has a high molecular weight, and has excellent effects in tensile strength, abrasion resistance, and resistance to wet road surfaces. .

The repeating unit derived from the conjugated diene-based monomer may mean a repeating unit formed when the conjugated diene-based monomer is polymerized, and the conjugated diene-based monomer is, for example, 1,3-butadiene, 2,3-dimethyl-1,3-butadiene. , Piperylene, 3-butyl-1,3-octadiene, isoprene, 2-phenyl-1,3-butadiene and 2-halo-1,3-butadiene (halo means a halogen atom) from the group consisting of. It may be one or more selected.

Meanwhile, the modified conjugated diene-based copolymer may be, for example, a copolymer further including a repeating unit derived from an aromatic vinyl monomer together with a repeating unit derived from the conjugated diene-based monomer.

The repeating unit derived from the aromatic vinyl monomer may mean a repeating unit formed when the aromatic vinyl monomer is polymerized, and the aromatic vinyl monomer is, for example, styrene, α-methylstyrene, 3-methylstyrene, 4-methylstyrene, and 4-propyl It may be one or more selected from the group consisting of styrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4-(p-methylphenyl)styrene, and 1-vinyl-5-hexylnaphthalene.

When the modified conjugated diene-based polymer is a copolymer containing repeating units derived from an aromatic vinyl monomer, the modified conjugated diene-based polymer contains 50 to 95% by weight, 55 to 90% by weight, or 60 to 90% by weight of repeating units derived from a conjugated diene-based monomer. As 90% by weight, it may contain 5 to 50% by weight, 10 to 45% by weight, or 10 to 40% by weight of the repeating unit derived from the aromatic vinyl monomer, and within this range, excellent rolling resistance, wet road surface resistance and abrasion resistance It works.

According to an embodiment of the present invention, the copolymer may be a random copolymer, and in this case, there is an effect of having an excellent balance between physical properties. The random copolymer may mean that the repeating units constituting the copolymer are randomly arranged.

The modified conjugated diene-based polymer according to an embodiment of the present invention has a number average molecular weight (Mn) of 10,000 g/mol to 2,000,000 g/mol, 10,000 g/mol to 1,000,000 g/mol, or 100,000 g/mol to 1,000,000 g /mol, and a weight average molecular weight (Mw) of 10,000 g/mol to 5,000,000 g/mol, 10,000 g/mol to 3,000,000 g/mol, or 100,000 g/mol to 2,000,000 g/mol, within this range It has excellent effect of rolling resistance and wet road surface resistance. As another example, the modified conjugated diene-based polymer may have a molecular weight distribution (Mw/Mn) of 1 to 5, 1 to 4, or 1 to 3, and within this range, the physical property balance between physical properties is excellent.

As another example, the modified conjugated diene-based polymer may have a Mooney viscosity at 100° C., 40 or more, 40 to 110, 40 to 90, or 50 to 80, and has excellent processability and productivity within this range. It works.

In addition, the modified conjugated diene-based polymer may have a vinyl content of 5% by weight or more, or 5% by weight to 50% by weight, and the glass transition temperature within this range can be adjusted to an appropriate range, so that rolling resistance and wet road surface resistance And there is an effect excellent in low fuel economy. Here, the vinyl content refers to the content of 1,2-added conjugated diene-based monomer, not 1,4-added, based on 100% by weight of the conjugated diene-based copolymer consisting of a monomer having a vinyl group and an aromatic vinyl-based monomer. I can.

Meanwhile, in the present invention, the terms'derived repeating unit' and'derived functional group' may refer to a component, structure, or the substance itself derived from a substance.

The method for preparing a modified conjugated diene-based polymer according to the present invention comprises polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in a hydrocarbon solvent containing an organometallic compound to prepare an organic metal-bound active polymer. Step (S1); And reacting with a denaturant including the active polymer and the compound represented by Formula 1 below (S2).

[Formula 1]

The definition of each substituent in Formula 1 is as defined above.

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.

According to an embodiment of the present invention, the compound represented by Chemical Formula 1 may be used in an amount of 0.01 mmol to 10 mmol based on a total of 100 g of monomers.

According to an embodiment of the present invention, the organometallic compound may be used in an amount of 0.01 mmol to 10 mmol, 0.05 mmol to 5 mmol, 0.1 mmol to 2 mmol, or 0.1 mmol to 1 mmol based on a total of 100 g of monomers.

Examples of the organometallic compound include methyl lithium, ethyl lithium, propyl lithium, n-butyl lithium, s-butyl lithium, t-butyl lithium, hexyl lithium, n-decyl lithium, t-octyl lithium, phenyl lithium, 1-naph Tilithium, n-eicosyllithium, 4-butylphenyllithium, 4-tolyllithium, cyclohexyllithium, 3,5-di-n-heptylcyclohexyllithium, 4-cyclopentyllithium, naphthyl sodium, naphthyl potassium , Lithium alkoxide, sodium alkoxide, potassium alkoxide, lithium sulfonate, sodium sulfonate, potassium sulfonate, lithium amide, sodium amide, potassium amide, and lithium isopropylamide.

Meanwhile, the polymerization of step (S1) may be carried out including a polar additive, and the polar additive may be added in an amount of 0.001 g to 50 g, 0.001 g to 10 g, or 0.005 g to 0.1 g based on a total of 100 g of monomers. have. In addition, the polar additives are tetrahydrofuran, ditetrahydrofurylpropane, diethyl ether, cycloamal ether, dipropyl ether, ethylene methyl ether, ethylene dimethyl ether, diethyl glycol, dimethyl ether, tertiary butoxyethoxyethane. , Bis(3-dimethylaminoethyl) ether, (dimethylaminoethyl) ethyl ether, trimethylamine, triethylamine, tripropylamine, and tetramethylethylenediamine may be one or more selected from the group consisting of, and preferably triethyl It may be an amine or tetramethylethylenediamine, and may be the same as or different from a polar additive that may be added when preparing the amino silane compound, and when the polar additive is included, a conjugated diene-based monomer or a conjugated diene-based monomer and When copolymerizing an aromatic vinyl-based monomer, there is an effect of inducing a random copolymer to be easily formed by compensating for a difference in reaction rate thereof.

The polymerization in step (S1) may be an anionic polymerization as an example, and a specific example may be a living anionic polymerization having an anionic active site at the polymerization end by a growth polymerization reaction by an anion. In addition, the polymerization in step (S1) may be elevated temperature polymerization, isothermal polymerization, or constant temperature polymerization (insulation polymerization), and the constant temperature polymerization includes polymerization by self-reaction heat without optionally applying heat after adding an organometallic compound. It may mean a polymerization method, and the elevated temperature polymerization may mean a polymerization method in which heat is arbitrarily applied after the organometallic compound is added to increase the temperature, and the isothermal polymerization is heat after the organometallic compound is added. It may mean a polymerization method in which the temperature of the polymerized product is kept constant by increasing heat by adding or taking away heat. In addition, the polymerization of step (S1) is an example, the polymerization may be carried out in a temperature range of -20 ℃ to 200 ℃, 0 ℃ to 150 ℃, or 10 ℃ to 120 ℃.

The active polymer prepared by the step (S1) may mean a polymer in which a polymer anion and an organic metal cation are bonded.

According to an embodiment of the present invention, the molar ratio of the denaturant containing the compound represented by Formula 1 and the organometallic compound may be 1:0.1 to 1:10, and within this range, the denaturation reaction of optimum performance can be performed. It is possible to obtain a conjugated diene polymer having a high modification rate.

The reaction in step (S2) is a denaturation reaction for introducing a functional group derived from the denaturant into the active polymer, and may be performed at 0°C to 90°C for 1 minute to 5 hours.

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

The method for preparing the modified conjugated diene-based polymer may further include at least one of the steps of recovering and drying a solvent and an unreacted monomer, if necessary, following the step (S2) of the present invention.

The denaturant according to the present invention may include a compound represented by the following Formula 1:

[Formula 1]

In Formula 1, the definition of each substituent is as defined above.

The modifier of the present invention has excellent affinity with inorganic fillers, particularly silica-based fillers, and thus has an effect of increasing dispersibility between the polymer modified from the modifier and the filler.

According to the present invention, a rubber composition containing the modified conjugated diene polymer is provided.

The rubber composition may contain the modified conjugated diene polymer in an amount of 10% by weight or more, 10% by weight to 100% by weight, or 20% by weight to 90% by weight, and within this range, tensile strength, abrasion resistance, etc. It has excellent mechanical properties and has an excellent balance between properties.

In addition, the rubber composition may further include other rubber components as necessary in addition to the modified conjugated diene-based polymer, and in this case, the rubber component may be included in an amount of 90% by weight or less based on the total weight of the rubber composition. As a specific example, the other rubber component may be included in an amount of 1 to 900 parts by weight based on 100 parts by weight of the modified conjugated diene-based polymer.

The rubber component may be, for example, natural rubber or synthetic rubber, and specific examples include 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.

The rubber composition may include, for example, 0.1 parts by weight to 200 parts by weight, or 10 parts by weight to 120 parts by weight of a filler based on 100 parts by weight of the modified conjugated diene-based polymer of the present invention. The filler may be a silica-based filler as an example, and a specific example may be wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, or colloidal silica, and preferably, the effect of improving fracture properties and wet It may be wet-type silica that has the most excellent wet grip effect. In addition, the rubber composition may further include a carbon black-based filler if necessary.

As another example, when silica is used as the filler, a silane coupling agent for improving reinforcement and low heat generation properties may be used together, and as a specific example, the silane coupling agent is bis(3-triethoxysilylpropyl)tetrasulfide , Bis(3-triethoxysilylpropyl)trisulfide, bis(3-triethoxysilylpropyl)disulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(3-trimethoxysilyl Propyl) tetrasulfide, bis(2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide Feed, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-trimethoxysilylpropylbenzothiazolyltetrasulfide, 3-triethoxysilylpropylbenzolyltetrasulfide, 3-triethoxysilylpropylmethacrylate monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, bis(3-diethoxymethylsilylpropyl)tetrasulfide, 3-mercaptopropyldimethoxymethyl Silane, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, dimethoxymethylsilylpropylbenzothiazolyltetrasulfide, and the like, any one or a mixture of two or more of them may be used. Preferably, when considering the effect of improving reinforcing properties, it 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 silica is introduced as a rubber component is used, the blending amount of the silane coupling agent is usually It may be less than the case, and accordingly, the silane coupling agent may be used in an amount of 1 to 20 parts by weight, or 5 to 15 parts by weight per 100 parts by weight of silica, and within this range, the effect as a coupling agent is While sufficiently exhibited, there is an effect of preventing the gelation of the rubber component.

The rubber composition according to an embodiment of the present invention may be sulfur crosslinkable, and 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, within this range, while securing the required elastic modulus and strength of the vulcanized rubber composition, low fuel economy It has an excellent effect.

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, a zinc white, It may further include stearic acid, a thermosetting resin, or a thermoplastic resin.

The vulcanization accelerator is a thiazole compound such as M (2-mercaptobenzothiazole), DM (dibenzothiazyl disulfide), CZ (N-cyclohexyl-2-benzothiazylsulfenamide), or DPG A guanidine-based compound such as (diphenylguanidine) may be used, and may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the rubber component.

The process oil acts as a softening agent in the rubber composition, and may be, for example, a paraffinic, naphthenic, or aromatic compound, and when considering tensile strength and abrasion resistance, when considering aromatic process oil price, hysteresis loss and low temperature characteristics Naphthenic or paraffinic process oil may be used. For example, 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 within this range, there is an effect of preventing a decrease in tensile strength and low heat generation (low fuel economy) of the vulcanized rubber.

Examples of the anti-aging agent include N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, 6-ethoxy-2 ,2,4-trimethyl-1,2-dihydroquinoline, or a high-temperature condensation product of diphenylamine and acetone, and the like, and 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 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, pancreas, or bead coated rubbers, and other tire members, anti-vibration rubber, belt conveyors, hoses, etc. It may be useful in the manufacture of various industrial rubber products.

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

The tire may include a tire or a tire tread.

Hereinafter, the present invention will be described in more detail by examples. However, the following examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example

Example 1

In a 20 L autoclave reactor, 270 g of styrene, 710 g of 1,3-butadiene, and 5,000 g of normal hexane, and 0.86 g of ditetrahydrofurylpropane (DTP, 2,2-di(2-tetrahydrofuryl) propane) as a polar additive were added. After that, the internal temperature of the reactor was raised to 40 °C. When the temperature inside the reactor reached 40° C., 4 mmol of n-butyllithium was added to the reactor to proceed with an adiabatic heating reaction. After 20 extra passes, 20 g of 1,3-butadiene was added, and the end of the polymer was capped with butadiene. After 5 minutes, 4 mmol of the compound represented by the following formula 1-1 was added, and the denaturation reaction was performed for 15 minutes. Thereafter, the polymerization reaction was stopped using ethanol, and 45 ml of a solution in which 0.3% by weight of the antioxidant BHT (butylated hydroxytoluene) was dissolved in hexane was added. The resulting polymer was put in hot water heated with steam and stirred to remove the solvent, and then roll-dried to remove the remaining amount of solvent and water, thereby preparing a modified conjugated diene-based polymer. The analysis results for the modified conjugated diene-based polymer thus prepared are shown in Table 1 below.

[Formula 1-1]

Example 2

In Example 1, it was carried out in the same manner as in Example 1, except that 2.7 mmol of the compound represented by Formula 1-1 was added.

Comparative Example 1

A commercially available LANXESS company's styrene-butadiene copolymer (5025-2HM grade) was used.

Comparative Example 2

In Example 1, it was carried out in the same manner as in Example 1, except that 4 mmol of chlorodimethylsilante was added instead of the compound represented by Formula 1-1.

Experimental example

Experimental Example 1

For each modified or unmodified conjugated diene-based polymer prepared in the above Examples and Comparative Examples, the styrene unit content and vinyl unit content in the conjugated diene-based polymer, weight average molecular weight (Mw, X10 ⁴ g/mol), and number average Molecular weight (Mn, X10 ⁴ g/mol), molecular weight distribution (MWD) and pattern viscosity (MV) were measured, respectively. The results are shown in Table 1 below.

The styrene unit content (SM, wt%) and vinyl content (Vinyl, wt%) in the conjugated diene polymer were measured and analyzed using Varian VNMRS 500 MHz NMR.

The weight average molecular weight (Mw) and number average molecular weight (Mn) were measured through GPC (Gel permeation chromatohraph) analysis, and the molecular weight distribution (MWD, Mw/Mn) was calculated from the measured molecular weights. Specifically, the GPC was used in combination with two columns of PLgel Olexis (Polymer Laboratories) and one column of PLgel mixed-C (Polymer Laboratories). When calculating the molecular weight, the GPC standard material was performed using polystyrene (PS).

The pattern viscosity (MV, (ML1+4, @100°C) MU) was measured using a Rotor Speed 2±0.02 rpm, Large Rotorfmf at 100°C using MV-2000 (ALPHA Technologies), and the sample used at this time Was left at room temperature (23±3℃) for at least 30 minutes, and then 27±3 g was collected, filled in the die cavity, and platen was operated for 4 minutes.

division Example Comparative example One 2 One 2 SM (wt%) 27 27 27 27 Vinyl (wt%) 43 43 43 43 Mw (X10 ⁴ g/mol) 43 51 69 50 Mn (X10 ⁴ g/mol) 34 39 39 31 MWD (Mw/Mn) 1.2 1.3 1.8 1.2 MV 68 72 61 64

Experimental Example 2

In order to compare and analyze the physical properties of the rubber composition including each modified or unmodified conjugated diene-based copolymer prepared in the above Examples and Comparative Examples and the molded article prepared therefrom, tensile properties, abrasion resistance, and wet road surface resistance were measured, respectively. The results are shown in Table 3 below.

1) Preparation of rubber specimen

Each modified or unmodified conjugated diene-based polymer of Examples and Comparative Examples was used as a raw material rubber, and was blended under the conditions shown in Table 2 below. The raw materials in Table 2 are each part by weight based on 100 parts by weight of rubber.

Specifically, the rubber specimen is kneaded through the first stage kneading and the second stage kneading. In the first stage kneading, raw material rubber (conjugated diene polymer), filler, organosilane coupling agent, process oil, zinc oxide, stearic acid, antioxidant, anti-aging agent, and wax are kneaded using a Banbari mixer with a temperature control device. I did. At this time, the temperature of the kneader was controlled at 70° C., and a first blend was obtained at a discharge temperature of 145° C. to 155° C. In the second stage kneading, the first blend was cooled to room temperature, and then the first blend, sulfur, rubber accelerator and vulcanization accelerator were added to the kneader, followed by mixing at a temperature of 100° C. or less to obtain a second blend. Thereafter, a rubber specimen was prepared through a curing process at 160° C. for 20 minutes.

2) tensile properties

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.

3) Viscoelastic properties

For viscoelastic properties, tan δ was measured by varying the strain at a frequency of 10 Hz and each measurement temperature (-60°C to 60°C) in a torsion mode using a dynamic mechanical analyzer (TA), and the result of Comparative Example 1 was used as a reference value. And expressed by indexing according to Equations 1 and 2 below. The higher the low temperature 0℃ tan δ index, the better the wet road surface resistance, and the higher the high temperature 60℃ tan δ index, the less hysteresis loss and the better low running resistance (fuel economy).

[Equation 1]

[Equation 2]

division Example Comparative example One 2 One 2 Tensile properties 300% modulus (kgf/cm ² ) 119 117 98 104 Tensile strength (kgf/cm ² ) 191 188 167 168 Viscoelasticity tan δ@0℃(Index) 116 112 100 98 tan δ@60℃(Index) 125 123 100 105

As shown in Table 3, the modified conjugated diene-based polymer according to the present invention was compared with Comparative Example 1, which is a commercially available copolymer, and Comparative Example 2, in which coupling/modification was performed using a silane-based compound not containing a functional group. It was confirmed that both tensile properties and viscoelastic properties were significantly improved.

Claims (12)

A modified conjugated diene-based polymer comprising a repeating unit derived from a conjugated diene-based monomer, and a functional group derived from a denaturant comprising a compound represented by the following formula 1-1 at one end:
[Formula 1-1]

In Formula 1-1, Me is a methyl group, and Et is an ethyl group. delete delete The method of claim 1,
The modified conjugated diene-based polymer further includes a repeating unit derived from an aromatic vinyl monomer. The method of claim 1,
The modified conjugated diene-based polymer has a number average molecular weight (Mn) of 10,000 g/mol to 2,000,000 g/mol. The method of claim 1,
The modified conjugated diene-based polymer is a modified conjugated diene-based polymer having a molecular weight distribution (Mw/Mn) of 1 to 5. Polymerizing a conjugated diene-based monomer or an aromatic vinyl-based monomer and a conjugated diene-based monomer in a hydrocarbon solvent containing an organometallic compound to prepare an organic metal-bonded active polymer (S1); And
A method for preparing a modified conjugated diene-based polymer comprising the step (S2) of reacting with a denaturant including the active polymer and a compound represented by the following formula 1-1:
[Formula 1-1]

In Formula 1-1, Me is a methyl group, and Et is an ethyl group. The method of claim 7,
The organic metal compound is a method for producing a modified conjugated diene-based polymer to be used in an amount of 0.01 mmol to 10 mmol based on a total of 100 g of monomers. The method of claim 7,
The organometallic compound is methyllithium, ethyllithium, propyllithium, n-butyllithium, s-butyllithium, t-butyllithium, hexyllithium, n-decyllithium, t-octyllithium, phenyllithium, 1-naphthyllithium , n-eicosyllithium, 4-butylphenyllithium, 4-tolyllithium, cyclohexyllithium, 3,5-di-n-heptylcyclohexyllithium, 4-cyclopentyllithium, naphthyl sodium, naphthyl potassium, lithium Alkoxide, sodium alkoxide, potassium alkoxide, lithium sulfonate, sodium sulfonate, potassium sulfonate, lithium amide, sodium amide, potassium amide and lithium isopropyl amide, wherein at least one selected from the group consisting of a modified conjugated diene polymer production method . The method of claim 7,
The polymerization of the step (S1) is a method for producing a modified conjugated diene-based polymer that is carried out including a polar additive. The method of claim 10,
The polar additives are tetrahydrofuran, ditetrahydrofurylpropane, diethyl ether, cycloamal ether, dipropyl ether, ethylene dimethyl ether, ethylene dimethyl ether, diethyl glycol, dimethyl ether, tertiary butoxyethoxyethane, bis (3-dimethylaminoethyl) ether, (dimethylaminoethyl) ethyl ether, trimethylamine, triethylamine, tripropylamine, and a method for producing a modified conjugated diene-based polymer of at least one selected from the group consisting of tetramethylethylenediamine. A denaturant comprising a compound represented by the following formula 1-1:
[Formula 1-1]

In Formula 1-1, Me is a methyl group, and Et is an ethyl group.