Modifier, modified conjugated diene polymer containing the same, and method for producing the polymer

Abstract

The present invention relates to a modifying agent which is useful for modifying a conjugated diene polymer, has excellent affinity with a filler, and can improve the blend properties of the conjugated diene polymer, a modified conjugated diene polymer containing a functional group derived from the modifying agent, and a method for producing the modified conjugated diene polymer.

Description

[Technical field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0178529 dated December 19, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a modifying agent which is useful for modifying a conjugated diene polymer, has excellent affinity with a filler, and can improve the blend properties of the conjugated diene polymer, a modified conjugated diene polymer containing a functional group derived from the modifying agent, and a method for producing the modified conjugated diene polymer. [Background technology]

[0003] In recent years, with the demand for lower fuel consumption for automobiles, there has been a demand for conjugated diene-based polymers as rubber materials for tires that have low rolling resistance, excellent abrasion resistance and tensile properties, as well as adjustment stability, as typified by wet skid resistance.

[0004] One method for reducing the rolling resistance of a tire is to reduce the hysteresis loss of vulcanized rubber, and the evaluation indexes for such vulcanized rubber are the rebound resilience, tan δ, Goodrich heat generation, etc. at 50° C. to 80° C. In other words, a rubber material that has high rebound resilience or low tan δ and Goodrich heat generation at the above temperatures is preferred.

[0005] Natural rubber, polyisoprene rubber, polybutadiene rubber, etc. are known as rubber materials with low hysteresis loss, but they have a problem of low wet skid resistance. In recent years, conjugated diene polymers or copolymers 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 content of vinyl structure and the content of styrene, which determine the physical properties of rubber, can be freely adjusted, and the molecular weight and physical properties can be adjusted by coupling, modification, etc. Therefore, the structure of the finally produced SBR or BR can be easily changed, and the movement of the chain ends can be reduced by bonding or modification of the chain ends, and the binding strength with fillers such as silica or carbon black can be increased, so SBR produced by solution polymerization is often used as a rubber material for tires.

[0006] When such SBR produced by solution polymerization 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 making it possible to adjust the physical properties required for tires, such as running resistance and braking force, as well as to reduce fuel consumption by appropriately adjusting the glass transition temperature. The SBR produced by solution polymerization is produced using an anionic polymerization initiator, and the chain ends of the formed polymer are bonded or modified using various modifiers before use. For example, U.S. Patent No. 4,397,994 presents a technology in which active anions at the chain ends of a polymer obtained by polymerizing styrene-butadiene in a non-polar solvent using an alkyl lithium, which is a monofunctional initiator, are bonded using a binder such as a tin compound.

[0007] Meanwhile, carbon black and silica are used as reinforcing fillers for tire treads, and when silica is used as a reinforcing filler, it has the advantage of improving low hysteresis loss and wet skid resistance. However, compared to carbon black with a hydrophobic surface, silica with a hydrophilic surface has a low affinity with rubber, and therefore has a disadvantage of poor dispersibility. Therefore, it is necessary to improve the dispersibility or use a separate silane coupling agent to bond silica and rubber. Therefore, a method of introducing a functional group having affinity and reactivity with silica to the end of a rubber molecule has been tried, but the effect is not sufficient. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] US4397994A Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide a modifier which is useful for modifying a conjugated diene polymer, has excellent affinity with a filler, and can improve the compounding properties of the conjugated diene polymer. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention provides a modifying agent having a novel structure.

[0011] (1) The present invention provides a denaturing agent represented by the following chemical formula 1:

[0012] [ka]

[0013] In the above Chemical Formula 1, A is an arylene group having 6 to 20 carbon atoms or a heteroarylene group having 5 to 20 carbon atoms; L1 and L2 each independently represent an alkylene group having 1 to 20 carbon atoms; L3 and L4 each independently represent an alkylene group having 1 to 20 carbon atoms; R1 to R6 are each independently an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, where at least one of R1 to R3 is an alkoxy group having 1 to 20 carbon atoms, and at least one of R4 to R6 is an alkoxy group having 1 to 20 carbon atoms.

[0014] (2) The present invention provides the modifying agent according to (1) above, wherein in Chemical Formula 1, A is an arylene group having 6 to 10 carbon atoms or a heteroarylene group having 5 to 10 carbon atoms.

[0015] (3) The present invention provides the modifying agent according to (1) or (2), wherein in Chemical Formula 1, L1 and L2 are each independently an alkylene group having 1 to 10 carbon atoms, and L1 and L2 are the same as each other, and L3 and L4 are each independently an alkylene group having 1 to 10 carbon atoms, and L3 and L4 are the same as each other.

[0016] (4) The present invention provides the modifying agent according to any one of (1) to (3) above, wherein in Chemical Formula 1, R1 to R6 are each independently an alkoxy group having 1 to 10 carbon atoms.

[0017] (5) The present invention provides the modifying agent according to any one of (1) to (4) above, wherein the modifying agent represented by Chemical Formula 1 is selected from compounds represented by the following Chemical Formula 1A and Chemical Formula 1B:

[0018] [ka]

[0019] [ka]

[0020] In the above Chemical Formula 1A and Chemical Formula 1B, The definitions of L1 to L4 and R1 to R6 are the same as those in Chemical Formula 1 above.

[0021] (6) The present invention provides the modifying agent according to any one of (1) to (5) above, wherein the modifying agent represented by Chemical Formula 1 is selected from compounds represented by the following Chemical Formula 1-1 and Chemical Formula 1-2:

[0022] [ka]

[0023] [ka] Effect of the Invention

[0024] By using the modifying agent according to the present invention, a modified conjugated diene-based polymer can be produced at a high modification rate, and a modified conjugated diene-based polymer having excellent affinity with a filler and exhibiting excellent processability and compounding properties can be produced. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The present invention will now be described in more detail so that the present invention may be easily understood.

[0026] The terms and words used in the description of the present invention and the claims should not be interpreted in a limited manner to their ordinary or dictionary meanings, but should be interpreted in a manner that is consistent with the technical idea of ​​the present invention, based on the principle that the inventors can appropriately define the concepts of terms in order to best describe their invention.

[0027] The present invention will be described in detail below.

[0028] Definition of Terms The term "substituted" used in the present invention means that the hydrogen of a functional group, an atomic group, or a compound is replaced with a specific substituent, and when the hydrogen of a functional group, an atomic group, or a compound is replaced with a specific substituent, one or more substituents may be present depending on the number of hydrogen present in the functional group, atomic group, or compound. In addition, when multiple substituents are present, each of the substituents may be the same or different from each other.

[0029] As used herein, the term "alkyl group" means a monovalent aliphatic saturated hydrocarbon group and can include both straight-chain alkyl groups, such as methyl, ethyl, propyl, and butyl, and branched alkyl groups, such as isopropyl, sec-butyl, tert-butyl, and neo-pentyl.

[0030] As used herein, the term "alkylene group" may refer to a divalent aliphatic saturated hydrocarbon such as methylene, ethylene, propylene, and butylene.

[0031] The term "alkoxy group" as used herein may mean any functional group, atomic group, or compound in which the terminal hydrogen of an alkyl group is replaced with an oxygen atom, such as methoxy, ethoxy, propoxy, and butoxy.

[0032] As used herein, the term "heteroalkyl group" may refer to an alkyl group in which any carbon atom in the alkyl group (excluding the terminal carbon atom) is replaced with one or more heteroatoms.

[0033] As used herein, the term "cycloalkyl group" may refer to a cyclic saturated hydrocarbon.

[0034] The term "aryl group" as used herein means an aromatic hydrocarbon and can be meant to include both monocyclic aromatic hydrocarbons, in which one ring is formed, or polycyclic aromatic hydrocarbons, in which two or more rings are linked together.

[0035] As used herein, the term "heteroaryl group" may be intended to include any aryl group in which one or more carbon atoms in the aryl group have been replaced with a heteroatom.

[0036] In the present invention, the terms "derived unit" and "derived functional group" can mean a component or structure originating from a certain substance, or the substance itself.

[0037] The present invention provides a denaturing agent represented by the following Chemical Formula 1:

[0038] [ka]

[0039] In the above Chemical Formula 1, A is an arylene group having 6 to 20 carbon atoms or a heteroarylene group having 5 to 20 carbon atoms; L1 and L2 each independently represent an alkylene group having 1 to 20 carbon atoms; L3 and L4 each independently represent an alkylene group having 1 to 20 carbon atoms; R1 to R6 are each independently an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, where at least one of R1 to R3 is an alkoxy group having 1 to 20 carbon atoms, and at least one of R4 to R6 is an alkoxy group having 1 to 20 carbon atoms.

[0040] Specifically, in Chemical Formula 1, A is an arylene group having 6 to 20 carbon atoms, or a heteroarylene group having 5 to 20 carbon atoms, and may be an arylene group having 6 to 10 carbon atoms, or a heteroarylene group having 5 to 10 carbon atoms. Specifically, A is an arylene group such as a phenylene group, a naphthalene group, a biphenylene group, an anthracenylene group, a phenanthrenylene group, or a fluorenylene group, and may be a heteroarylene group containing one or more of O, N, S, and P atoms as a hetero element, and may be a pyridinylene group, a pyrimidinylene group, a triazinylene group, a thiophenylene group, a furanylene group, a dibenzothiophenylene group, a dibenzofuranylene group, a carbazolylene group, or the like.

[0041] Specifically, in the above Chemical Formula 1, L1 to L4 are each independently an alkylene group having 1 to 20 carbon atoms, L1 and L2 are each independently an alkylene group having 1 to 10 carbon atoms, and L1 and L2 are the same as each other, and L3 and L4 are each independently an alkylene group having 1 to 10 carbon atoms, and L3 and L4 may be the same as each other. For example, L1 and L2 may be the same as each other and an alkylene group having 1 to 10 carbon atoms, an alkylene group having 1 to 6 carbon atoms, a methylene group, an ethylene group, a propylene group, a butylene group, or the like, and L3 and L4 may be the same as each other and an alkylene group having 1 to 10 carbon atoms, an alkylene group having 1 to 6 carbon atoms, a methylene group, an ethylene group, a propylene group, a butylene group, or the like, and L1 to L4 may all be a propylene group.

[0042] Specifically, in Chemical Formula 1, R1 to R6 are an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, where at least one of R1 to R3 is an alkoxy group having 1 to 20 carbon atoms, and at least one of R4 to R6 is an alkoxy group having 1 to 20 carbon atoms. More specifically, R1 to R6 may all be an alkoxy group having 1 to 10 carbon atoms, such as an alkoxy group having 1 to 6 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a methoxy group, or an ethoxy group.

[0043] Specifically, the modifying agent represented by the formula 1 may be selected from the compounds represented by the following formulas 1A and 1B.

[0044] [ka]

[0045] [ka]

[0046] In the above Chemical Formula 1A and Chemical Formula 1B, The definitions of L1 to L4 and R1 to R6 are the same as those in Chemical Formula 1 above.

[0047] The modifier represented by Chemical Formula 1 contains more alkoxysilane functional groups than conventional modifiers, making it possible to produce a high molecular weight modified conjugated diene polymer, and has silica affinity functional groups such as O and N, which allows it to exhibit excellent compounding properties through interaction with silica-based fillers. In addition, the modifier represented by Chemical Formula 1 itself is structurally planar, making it easy to undergo a bonding reaction with the polymer during the modification process.

[0048] The modifying agent represented by Chemical Formula 1 may be selected from compounds represented by Chemical Formula 1-1 and Chemical Formula 1-2 below.

[0049] [ka]

[0050] [ka]

[0051] The denaturant represented by Chemical Formula 1 according to the present invention may be prepared by reacting a compound represented by Chemical Formula 2 below with a compound represented by Chemical Formula 3 or Chemical Formula 4 below.

[0052] [ka]

[0053] [ka]

[0054] [ka]

[0055] In the above formula 2, A1 and A2 are each independently a halogen element, specifically Cl.

[0056] In the chemical formulas 2 to 4, the definition of each substituent is as defined above.

[0057] In the above step, the compound represented by Chemical Formula 2 and the compound represented by Chemical Formula 3 or Chemical Formula 4 may be reacted in a molar ratio of 1:1.5 to 1:5.0, a molar ratio of 1:1.5 to 1:3.0, or a molar ratio of 1:1.5 to 1:2.5.

[0058] In the above step, the reaction of the compound represented by Chemical Formula 2 with the compound represented by Chemical Formula 3 or Chemical Formula 4 may be carried out at a temperature of 20 to 200°C, 30 to 180°C, or 40 to 150°C for 1 to 72 hours.

[0059] By using the modifying agent represented by Chemical Formula 1 of the present invention, a modified conjugated diene polymer containing a repeating unit derived from a conjugated diene monomer and containing a functional group derived from the modifying agent represented by Chemical Formula 1 at at least one terminal can be produced.

[0060] The repeating unit derived from the conjugated diene monomer means a repeating unit formed by polymerization of a conjugated diene monomer, and the conjugated diene monomer may be, for example, one or more selected from the group consisting of 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).

[0061] Meanwhile, the modified conjugated diene copolymer may be, for example, a copolymer further including a repeating unit derived from an aromatic vinyl monomer in addition to the repeating unit derived from the conjugated diene monomer.

[0062] The repeating unit derived from the aromatic vinyl monomer means a repeating unit formed by polymerization of the aromatic vinyl monomer, and the aromatic vinyl monomer may be, for example, one or more selected from the group consisting of styrene, α-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4-(p-methylphenyl)styrene, and 1-vinyl-5-hexylnaphthalene.

[0063] When the modified conjugated diene polymer is a copolymer containing a repeating unit derived from an aromatic vinyl monomer, the modified conjugated diene polymer may contain a repeating unit derived from a conjugated diene monomer at a minimum of 20% by weight, 30% by weight, 40% by weight, 50% by weight, 55% by weight, or 60% by weight, and a maximum of 95% by weight, 90% by weight, or 80% by weight, and may contain a repeating unit derived from an aromatic vinyl monomer at a minimum of 5% by weight, 10% by weight, or 20% by weight, and a maximum of 80% by weight, 70% by weight, 60% by weight, 55% by weight, 50% by weight, 45% by weight, or 40% by weight. When the amount is within this range, the effect of excellent rolling resistance, wet skid resistance, and abrasion resistance is obtained.

[0064] According to an embodiment of the present invention, the copolymer may be a random copolymer, which has an excellent balance between the physical properties. The random copolymer may mean a copolymer in which repeating units constituting the copolymer are randomly arranged.

[0065] The modified conjugated diene polymer according to one embodiment of the present invention may have a number average molecular weight (Mn) of 10,000 g / mol to 2,000,000 g / mol, 50,000 g / mol to 1,800,000 g / mol, or 120,000 g / mol to 1,500,000 g / mol, and a weight average molecular weight (Mw) of 10,000 g / mol to 5,000,000 g / mol, 100,000 g / mol to 3,500,000 g / mol, or 120,000 g / mol to 2,000,000 g / mol. When the weight average molecular weight is within this range, the polymer has excellent rolling resistance and wet skid resistance. As yet another example, the modified conjugated diene polymer may have a molecular weight distribution (Mw / Mn) of 1.0 to 8.0, 1.0 to 4.0, or 1.0 to 3.5. When the molecular weight distribution is within this range, an excellent balance between physical properties is achieved.

[0066] Here, the weight average molecular weight (Mw) and number average molecular weight (Mn) are polystyrene equivalent molecular weights analyzed by gel permeation chromatography (GPC), and the molecular weight distribution (Mw / Mn) is also called polydispersity and is calculated as the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn).

[0067] As yet another example, the modified conjugated diene polymer may have a Mooney viscosity of 20 to 150 at 100° C., and 20 to 150 at 140° C. When the viscosity is within this range, the effect of excellent processability and productivity is obtained.

[0068] Here, the Mooney viscosity is measured using a Mooney viscometer, for example, a large rotor of MV2000E (ALPHA Technologies), under conditions of 100° C. and 140° C., rotor speed 2±0.02 rpm. Specifically, the polymer is left at room temperature (23±5° C.) for 30 minutes or more, and then 27±3 g is taken and filled into the die cavity, and the platen is operated to apply torque for measurement.

[0069] In addition, the modified conjugated diene polymer may have a vinyl content of 5% by weight or more, 10% by weight or more, or 10% by weight to 60% by weight. When the vinyl content is within this range, the glass transition temperature is adjusted to an appropriate range, so that the rolling resistance, wet skid resistance, and fuel economy are excellent. Here, the vinyl content may mean the content of 1,2-added conjugated diene monomer, not 1,4-added, relative to 100% by weight of a conjugated diene copolymer composed of a vinyl group-containing monomer and an aromatic vinyl monomer.

[0070] On the other hand, the terms "repeating unit derived from," "functional group derived from," and "group derived from" used in the present invention can mean a component or structure originating from a certain substance, or the substance itself.

[0071] Method for producing modified conjugated diene polymer The present invention also provides a method for producing the modified conjugated diene polymer.

[0072] The method for producing the modified conjugated diene polymer according to one embodiment of the present invention includes the steps of: (S1) polymerizing a conjugated diene monomer or an aromatic vinyl monomer and a conjugated diene monomer in a hydrocarbon solvent containing an organometallic compound to produce an activated polymer having an organometallic bond thereto (Step 1); and (S2) reacting the activated polymer with a modifier represented by the following chemical formula 1 (Step 2).

[0073] [ka]

[0074] The definition of each substituent in the formula 1 is as defined above.

[0075] Step 1 is a step for preparing an activated polymer bound to an organometallic compound, and can be carried out by polymerizing a conjugated diene monomer, or an aromatic vinyl monomer and a conjugated diene monomer in a hydrocarbon solvent containing an organometallic compound.

[0076] The hydrocarbon solvent is not particularly limited, and 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.

[0077] The conjugated diene monomer and the aromatic vinyl monomer are as defined above.

[0078] According to one embodiment of the present invention, the organometallic compound may be used in an amount of 0.01 to 10 mmol, 0.05 to 5 mmol, 0.1 to 2 mmol, 0.1 to 1 mmol, or 0.15 to 0.8 mmol based on a total of 100 g of the monomers.

[0079] The organometallic compound may be, for example, one or more selected from the group consisting of 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 isopropylamide.

[0080] On the other hand, the polymerization in step 1 may be carried out by 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, 0.005 g to 0.2 g, or 0.01 g to 0.2 g based on a total of 100 g of the monomers.

[0081] In addition, the polar additive is at least one selected from the group consisting of tetrahydrofuran, 2,2-di(tetrahydrofuryl)propane, diethyl ether, cyclopentyl ether, dipropyl ether, ethylene dimethyl ether, diethyl glycol, dimethyl ether, tertiary butoxyethoxyethane, bis(3-dimethylaminoethyl)ether, (dimethylaminoethyl)ethyl ether, trimethylamine, triethylamine, tripropylamine, and tetramethylethylenediamine, and may be specifically triethylamine or tetramethylethylenediamine. When the polar additive is included, when a conjugated diene monomer or a conjugated diene monomer and an aromatic vinyl monomer are copolymerized, the difference in reaction rate between them is complemented, thereby inducing the formation of a random copolymer easily.

[0082] The polymerization in step 1 may be, for example, anionic polymerization, and for a specific example, living anionic polymerization having an anionic active site at the polymerization end by a growth polymerization reaction by anion. The polymerization in step 1 may be temperature-rise polymerization, isothermal polymerization, or constant temperature polymerization (adiabatic polymerization). The constant temperature polymerization refers to a polymerization method including a step of polymerizing with the reaction heat of the organometallic compound itself without adding any heat after the organometallic compound is added, the temperature-rise polymerization refers to a polymerization method in which the temperature is increased by adding any heat after the organometallic compound is added, and the isothermal polymerization refers to a polymerization method in which the temperature of the polymer is maintained constant by adding heat to increase the heat or removing heat after the organometallic compound is added.

[0083] The polymerization in step 1 may be carried out at a temperature range of, for example, -20 to 80°C, 0 to 80°C, 10 to 80°C, or 10 to 70°C.

[0084] The activated polymer prepared in step 1 may refer to a polymer in which a polymer anion and an organometallic cation are bonded.

[0085] Step 2 is a step of reacting the activated polymer with the modifying agent represented by Chemical Formula 1 to prepare a modified conjugated diene-based polymer.

[0086] According to an embodiment of the present invention, the modifying agent represented by Formula 1 may be used in an amount of 0.1 to 100 g, 0.1 to 50 g, specifically 0.1 to 25 g, based on a total of 100 g of monomers.

[0087] According to one embodiment of the present invention, the modifying agent represented by Chemical Formula 1 and the organometallic compound may be used in a molar ratio of 1:0.1 to 1:10, a molar ratio of 1:0.1 to 1:5, or a molar ratio of 1:0.2 to 1:4. When the ratio is within this range, a modification reaction with optimal performance can be performed.

[0088] The reaction in step 2 is a modification reaction for introducing a functional group derived from the modifying agent into the activated polymer, and may be carried out at 0° C. to 90° C. for 1 minute to 5 hours.

[0089] According to one embodiment of the present invention, the method for producing the modified conjugated diene polymer may be carried out by a batchwise polymerization method or a continuous polymerization method including one or more reactors.

[0090] As an example, the method for producing the modified conjugated diene-based polymer may further include, following step 2 of the present invention, one or more steps of recovering and drying the solvent and unreacted monomers, if necessary.

[0091] Rubber composition Furthermore, the present invention provides a rubber composition containing the modified conjugated diene-based polymer.

[0092] The rubber composition according to one embodiment of the present invention 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. When the amount is within this range, the rubber composition has excellent mechanical properties such as tensile strength and abrasion resistance, and has an excellent balance between the various physical properties.

[0093] The rubber composition may further contain other rubber components, if necessary, in addition to the modified conjugated diene polymer, and in this case, the rubber components may be contained 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 components may be contained in an amount of 1 part by weight to 900 parts by weight based on 100 parts by weight of the modified conjugated diene polymer.

[0094] The rubber component may be, for example, natural rubber or synthetic rubber, and specific examples thereof include natural rubber (NR) containing cis-1,4-polyisoprene; modified natural rubbers such as epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber, which are obtained by modifying or refining the general natural rubber; styrene-butadiene copolymers (SBR), polybutadiene (BR), polyisoprene (IR), butyl rubber (IIR), ethylene-propylene copolymers, polyisobutylene-co-isoprene, The rubber may be a synthetic rubber such as 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, halogenated butyl rubber, or the like, and any one or a mixture of two or more of these may be used.

[0095] The rubber composition may contain, for example, 0.1 to 200 parts by weight, or 10 to 120 parts by weight of a filler relative to 100 parts by weight of the modified conjugated diene polymer of the present invention. The filler may be, for example, a silica-based filler, and specific examples thereof may include wet silica (hydrated silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, colloidal silica, etc., and preferably wet silica, which has the highest effect of improving fracture properties and wet grip properties. The rubber composition may further contain a carbon black-based filler as necessary.

[0096] As another example, when silica is used as the filler, a silane coupling agent for improving reinforcing properties and low heat generation properties may be used together.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-dimethylthiocarbamoyltetrasulfide, 3-triethoxy ... silyl tetrasulfide, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropyl benzothiazolyl tetrasulfide, 3-triethoxysilylpropyl benzolyl tetrasulfide, 3-triethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis(3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyl dimethoxymethyl silane, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyl tetrasulfide, or dimethoxymethylsilylpropyl benzothiazolyl tetrasulfide, and any one or a mixture of two or more of these can be used. Preferably, in consideration of the effect of improving reinforcing properties, bis(3-triethoxysilylpropyl) polysulfide or 3-trimethoxysilylpropyl benzothiazyl tetrasulfide may be used.

[0097] In addition, the rubber composition according to one embodiment of the present invention uses a modified conjugated diene polymer in which a functional group having high affinity with silica is introduced into the active site as a rubber component, so that the amount of the silane coupling agent can be reduced more than usual. Therefore, 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. When the amount is within this range, the effect of the coupling agent is sufficiently exhibited, while the gelation of the rubber component is prevented.

[0098] The rubber composition according to one 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 to 10 parts by weight per 100 parts by weight of the rubber component. When the amount is within this range, the vulcanized rubber composition can ensure the required elastic modulus and strength, and also has an effect of excellent fuel efficiency.

[0099] In addition to the above components, the rubber composition according to an embodiment of the present invention may further include various additives commonly used in the rubber industry, specifically, a vulcanization accelerator, a process oil, a plasticizer, an antioxidant, a scorch inhibitor, zinc white, stearic acid, a thermosetting resin, or a thermoplastic resin.

[0100] As the vulcanization accelerator, for example, a thiazole-based compound such as M (2-mercaptobenzothiazole), DM (dibenzothiazyl disulfide), CZ (N-cyclohexyl-2-benzothiazylsulfenamide), or a guanidine-based compound such as DPG (diphenylguanidine) can be used, and may be contained in an amount of 0.1 to 5 parts by weight per 100 parts by weight of the rubber component.

[0101] The process oil acts as a softener in the rubber composition and may be, for example, a paraffinic, naphthenic, or aromatic compound, and aromatic process oils can be used in consideration of tensile strength and abrasion resistance, and naphthenic or paraffinic process oils can be used in consideration of hysteresis loss and low temperature properties. The process oil may be contained in an amount of 100 parts by weight or less per 100 parts by weight of the rubber component, and within this range, it is effective in preventing a decrease in the tensile strength and low heat generation property (fuel economy) of the vulcanized rubber.

[0102] The antioxidant may be, for example, N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, or a high-temperature condensate of diphenylamine and acetone, and may be used in an amount of 0.1 to 6 parts by weight per 100 parts by weight of the rubber component.

[0103] The rubber composition according to one embodiment of the present invention is obtained by kneading the rubber composition according to the compounding recipe using a kneading machine such as a Banbury mixer, a roll, or an internal mixer. After molding and processing, a vulcanization process is performed to obtain a rubber composition having low heat build-up and excellent abrasion resistance.

[0104] As a result, the rubber composition is useful in the production of tire components such as tire treads, undertreads, sidewalls, carcass coating rubber, belt coating rubber, bead fillers, chafers, and bead coating rubber, as well as various industrial rubber products such as dustproof rubber, belt conveyors, and hoses.

[0105] The present invention also provides a tire produced using the rubber composition.

[0106] The tire may include a tire or a tire tread.

[0107] Working Example The present invention will be described in more detail with reference to the following examples. However, the following examples are merely for the purpose of illustrating the present invention, and the scope of the present invention is not limited thereto.

[0108] Manufacturing Example 1 (1) Synthesis of 1,4-bis(3-chloropropoxy)benzene In a 250 mL flask, hydroquinone (5.0 g, 45.4 mmol), 1-bromo-3-chloropropane (11.2 g), potassium phosphate (38.56 g), and methanol (45.4 mL) were placed and refluxed overnight. After the reaction, the mixture was quenched with water and dichloromethane. The product was finally obtained by drying. 1 H NMR(CDCl3, 500 MHz): 6.84 ppm(s, 4H), 4.07 ppm(m, 4H), 3.74 ppm(m, 4H), 2.21 ppm(m, 4H)

[0109] (2) Synthesis of 3,3'-(1,4-phenylenebis(oxy)bis(N,N-bis(3-(trimethoxysilyl)propyl)propan-1-amine) In a 100 mL flask, 1,4-bis(3-chloropropoxy)benzene (5.7 g, 21.8 mmol), trimethylamine (4.6 mL), and bis(3-(trimethoxysilyl)propyl)amine (15.7 mL) were placed and stirred overnight at 150° C. After completion of the reaction, the product was obtained by filtration and drying in vacuum. The H nuclear magnetic resonance spectroscopy spectrum was observed and it was confirmed that the compound was represented by the following chemical formula. 1 H NMR(CDCl3, 500 MHz): 6.80 ppm(s, 4H), 3.93 ppm(m, 4H), 3.55 ppm(s, 36H), 2.57 ppm(m, 4H), 2.41 ppm(m, 8H), 1.86 ppm(m, 4H), 1.53 ppm(m, 8H), 0.60 ppm(m, 8H)

[0110] [ka]

[0111] Manufacturing Example 2 (1) Synthesis of 1,5-bis(3-chloropropoxy)naphthalene In a 250 mL flask, naphthalene-1,5-diol (5.0 g, 31.2 mmol), 1-bromo-3-chloropropane (7.72 g), potassium phosphate (26.5 g), and methanol (31.2 mL) were placed and refluxed overnight. After the reaction, the mixture was quenched with water and dichloromethane. The product was finally obtained by drying. 1 H NMR(CDCl3, 500 MHz): 7.81 ppm(m, 2H), 7.38 ppm(m, 2H), 6.86 ppm(m, 2H), 4.28 ppm(m, 4H), 3.70 ppm(m, 4H), 2.46 ppm(m, 4H)

[0112] (2) Synthesis of 3,3'-(naphthalene-1,5-diylbis(oxy))bis(N,N-bis(3-(trimethoxysilyl)propyl)propan-1-amine) In a 100 mL flask, 1,5-bis(3-chloropropoxy)naphthalene (5.1 g, 16.3 mmol), trimethylamine (6.8 mL), and bis(3-(trimethoxysilyl)propyl)amine (11.8 mL) were placed and stirred overnight at 150° C. After completion of the reaction, the product was obtained by filtration and drying in vacuum. The H nuclear magnetic resonance spectroscopy spectrum was observed and it was confirmed that the compound was represented by the following chemical formula.

[0113] 1 H NMR(CDCl3, 500 MHz): 7.79 ppm(s, 2H), 7.33 ppm(s, 2H), 4.18 ppm(m, 4H), 3.55 ppm(s, 36H), 2.95 ppm(m, 4H), 2.62 ppm(m, 4H), 1.67 ppm(m, 8H), 1.31 ppm(m, 8H), 0.62 ppm(m, 8H)

[0114] [ka]

[0115] Example 1 Into a 20L autoclave reactor, 4.733g of n-hexane, 375.0g of styrene, 593.8g of 1,3-butadiene, and 1.4g of N,N,N',N'-tetramethylethylenediamine (TMEDA) as a polar additive were added, followed by 5.0g of n-butyllithium (10wt% in n-hexane), and the internal temperature of the reactor was adjusted to 40°C to carry out an adiabatic heating reaction. After about 30 minutes, 31.3g of 1,3-butadiene was added to cap the ends of the polymer with butadiene.

[0116] Then, 2.0 g of the compound represented by Chemical Formula 1-1 prepared in Preparation Example 1 was added as a modifier ([TMEDA]:[act.Li] = 3.1:1 molar ratio, [modifier]:[act.Li] = 0.3:1 molar ratio). Then, the reaction was stopped using ethanol, and 17 g of a solution in which the antioxidant Wingstay K was dissolved in hexane at 30 wt% was added. The resulting polymer was placed in hot water heated with steam, stirred to remove the solvent, and roll-dried to remove the remaining solvent and water, producing a modified styrene-butadiene copolymer.

[0117] Example 2 A modified conjugated diene polymer was produced in the same manner as in Example 1, except that 2.2 g of the compound represented by Chemical Formula 1-2 produced in Preparation Example 2 was added as the modifying agent.

[0118] Comparative Example 1 A modified styrene-butadiene copolymer was produced in the same manner as in Example 1, except that 0.64 g of SiCl4 was used as a modifier and the molar ratio of [modifier]:[act.Li] was 0.48:1.

[0119] Comparative Example 2 A modified styrene-butadiene copolymer was produced in the same manner as in Example 1, except that 0.97 g of N-methyl-3-(trimethoxysilyl)-N-(3-(trimethoxysilyl)propyl)propan-1-amine was used as the modifier, and the molar ratio of [modifier]:[act.Li] was 0.35:1.

[0120] Comparative Example 3 A modified styrene-butadiene copolymer was produced in the same manner as in Example 1, except that 1.4 g of tris(3-(trimethoxysilyl)propyl)amine was used as the modifier and the molar ratio of [modifier]:[act.Li] was 0.36:1.

[0121] Experimental Example 1 The modified conjugated diene polymers prepared in the examples and comparative examples were examined for the styrene unit content, vinyl content, weight average molecular weight (Mw, ×10 3 g / mol), number average molecular weight (Mn, ×10 3 g / mol), molecular weight distribution (MWD), and Mooney viscosity (MV) were measured, respectively.

[0122] 1) Styrene bond content and 1,2-vinyl bond content The styrene bond content (SM) and 1,2-vinyl bond content (Vi) in each polymer were measured and analyzed using a Varian VNMRS 500 MHz NMR. During NMR measurement, 1,1,2,2-tetrachloroethane was used as the solvent, and the solvent peak was calculated at 6.00 ppm. The styrene unit bond content and 1,2-vinyl bond content were calculated using the peaks of random styrene from 7.2 to 6.9 ppm, block styrene from 6.9 to 6.2 ppm, 1,4-vinyl and 1,2-vinyl from 5.8 to 5.1 ppm, and 1,2-vinyl from 5.1 to 4.5 ppm.

[0123] 2) Weight average molecular weight, number average molecular weight, molecular weight distribution The weight average molecular weight (Mw) and number average molecular weight (Mn) were measured by gel permeation chromatograph (GPC) analysis, and the molecular weight distribution (MWD, Mw / Mn) was calculated from the measured molecular weights.

[0124] Specifically, the GPC was performed using a combination of two PLgel Olexis (Polymer Laboratories) columns and one PLgel mixed-C (Polymer Laboratories) column, and the newly replaced columns were all mixed bed type columns. In addition, when calculating the molecular weight, PS (polystyrene) was used as the GPC standard material.

[0125] 3) Mooney Viscosity The Mooney viscosity (MV, (ML1+4, @100°C MU) was measured at 100°C using MV-2000 (ALPHA Technologies) at a rotor speed of 2±0.02 rpm and a large rotor. The sample used was left at room temperature (23±5°C) for 30 minutes or more, and then 27±3 g of the sample was taken and filled into the die cavity. The platen was operated and the measurement was performed for 4 minutes.

[0126] [Table 1]

[0127] As shown in the above results, the modified conjugated diene-based polymer of the present invention using the modifier represented by Chemical Formula 1 according to the present invention showed a significantly higher molecular weight than the comparative example, but the increase in Mooney viscosity was not relatively large. This result indicates that the modified conjugated diene-based polymer prepared in the example has a star-shaped polymer structure. In addition, it can be seen that the modified conjugated diene-based polymer of the example having such a structure should have improved processability and excellent wear performance due to its high molecular weight characteristics.

[0128] Experimental Example 2 In order to compare and analyze the physical properties of the rubber compositions containing the modified conjugated diene-based polymers prepared in the examples and comparative examples, and the molded articles prepared therefrom, the tensile properties, abrasion resistance, and wet skid resistance were measured, respectively.

[0129] 1) Preparation of rubber test specimens The modified conjugated diene polymers of the examples and comparative examples were used as raw rubber and were compounded under the compounding conditions shown in the following Table 2. The raw materials in Table 2 are each in parts by weight based on 100 parts by weight of rubber.

[0130] [Table 2]

[0131] Specifically, the rubber test pieces are kneaded through a first stage kneading and a second stage kneading. In the first stage kneading, raw rubber, silica (filler), an organic silane coupling agent (X50S, Evonik), process oil (TDAE oil), zinc oxide (ZnO), stearic acid, an antioxidant (TMQ(RD) (2,2,4-trimethyl-1,2-dihydroquinoline polymer), an anti-aging agent (6PPD ((dimethylbutyl)-N-phenyl-phenylenediamine), and a wax (Microcrystaline Wax) was mixed into the mixer. At this time, the temperature of the mixer was controlled to obtain a primary compound at a discharge temperature of 150°C. In the second mixing stage, the primary compound was cooled to room temperature, and then the primary compound, sulfur powder, rubber accelerator (DPG (diphenyl guanidine)), and vulcanization accelerator (CZ (N-cyclohexyl-2-benzothiazylsulfenamide)) were added to the mixer and mixed at a temperature of 100°C or less to obtain a secondary compound. Then, a curing process was carried out at 160°C for 20 minutes to produce rubber test pieces.

[0132] 2) Tensile properties For the tensile properties, each test piece was prepared according to the tensile test method of ASTM412, and the tensile stress at 300% elongation (300% modulus), breaking strength (tensile strength), and tensile modulus of the test pieces were measured.

[0133] Specifically, the tensile properties were measured at room temperature at a speed of 50 cm / min using a Universal Test Machine 4204 (Instron Corp.) tensile tester. The results in Table 3 are shown as an Index (%) based on the results of Comparative Example 1, with a higher value indicating better properties.

[0134] 3) Viscoelastic properties The viscoelastic properties were measured using a dynamic mechanical analyzer (manufactured by TA) in strain mode, with a frequency of 10 Hz, and with varying deformation at each measurement temperature (-60°C to 60°C). The Payne effect was expressed as the difference between the minimum and maximum values ​​at deformations of 0.28% to 40%. A higher tan δ at a low temperature of 0°C means better wet skid resistance, and a lower tan δ at a high temperature of 60°C means less hysteresis loss and better rolling resistance (fuel economy). However, the results in Table 3 are indexed using the measured values ​​in Comparative Example 1 as the reference value, and therefore the higher the value, the better the performance.

[0135] 4) Processability characteristics The Mooney viscosity (MV, (ML1+4, at 100°C MU) of the secondary blend obtained during the preparation of the rubber test specimens 1) was measured, and the processability characteristics of each polymer were compared and analyzed. In this regard, the lower the measured Mooney viscosity value, the better the processability characteristics. However, the results in Table 3 are shown as indexes using the measured value of Comparative Example 1 as the reference value, so the higher the value, the better the characteristics.

[0136] Specifically, using a large rotor on an MV-2000 (ALPHA Technologies), each secondary compound was left at room temperature (23±5°C) for 30 minutes or more at 100°C with a rotor speed of 2±0.02 rpm, and then 27±3 g was taken and filled into the die cavity, and the platen was operated to measure for 4 minutes.

[0137] 5) Abrasion resistance (DIN abrasion test) Each rubber test piece was subjected to a DIN abrasion test according to ASTM D5963, and the results were expressed as the DIN loss index (loss volume index: ARIA (Abration resistance index, Method A)). The higher the value, the better the performance.

[0138] [Table 3]

[0139] As shown in Table 3, it was confirmed that the modified conjugated diene-based polymers of the examples had the effect of improving the tensile properties, viscoelastic properties, abrasion resistance, and processability properties in a well-balanced manner.

[0140] From the above results, it was confirmed that the modified conjugated diene polymer of the present invention can form a high molecular weight polymer by containing a functional group derived from the modifier represented by Chemical Formula 1, and that a rubber composition containing the same has improved abrasion resistance properties. In addition, it has excellent affinity with fillers, which means that the processability and tensile properties of the rubber composition containing the same are all improved. From this, it can be seen that the modified conjugated diene polymer of the present invention, modified with the modifier represented by Chemical Formula 1, has a remarkable effect that cannot be achieved by a polymer modified with another modifier of a similar structure.

Claims

1. A modifying agent represented by the following chemical formula 1. 【Chemistry 1】 (In the above Chemical Formula 1, A is an arylene group having 6 to 20 carbon atoms or a heteroarylene group having 5 to 20 carbon atoms; L １ and L ２ are each independently an alkylene group having 1 to 20 carbon atoms, L ３ and L ４ are each independently an alkylene group having 1 to 20 carbon atoms, R １ ~R ６ are each independently an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, where R １ ~R ３ At least one of R is an alkoxy group having 1 to 20 carbon atoms; ４ ~R ６ At least one of the groups is an alkoxy group having 1 to 20 carbon atoms.

2. In the above Chemical Formula 1, 2. The modifying agent according to claim 1, wherein A is an arylene group having 6 to 10 carbon atoms or a heteroarylene group having 5 to 10 carbon atoms.

3. In the above Chemical Formula 1, L １ and L ２ are each independently an alkylene group having 1 to 10 carbon atoms; L １ and L ２ are identical to each other, L ３ and L ４ are each independently an alkylene group having 1 to 10 carbon atoms; L ３ and L ４ The denaturing agent of claim 1 , wherein:

4. In the above Chemical Formula 1, R １ ~R ６ and each independently represent an alkoxy group having 1 to 10 carbon atoms.

5. The modifying agent according to claim 1 , wherein the modifying agent represented by Chemical Formula 1 is selected from compounds represented by the following Chemical Formula 1A and Chemical Formula 1B: 【Chemistry 2】 (In the above Chemical Formula 1A and Chemical Formula 1B, L １ ~L ４ , R １ ~R ６ is defined as in Chemical Formula 1.

6. The modifying agent according to claim 1, wherein the modifying agent represented by Chemical Formula 1 is selected from the compounds represented by the following Chemical Formulas 1-1 and 1-2. 【Chemistry 3】

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