Modified conjugated diene polymer and rubber composition containing same

Abstract

The present invention relates to a modified conjugated diene polymer having a well-balanced and excellent wet skid resistance and abrasion resistance, and a rubber composition containing the same. The modified conjugated diene polymer contains repeating units derived from a conjugated diene monomer and functional groups derived from a modifier, and by controlling the microstructure of the polymer, the glass transition onset temperature (T g-on ) and glass transition end temperature (offset, T g-off ) is 10°C or more and 30°C or less, the effect of providing a well-balanced, excellent wet skid resistance and running resistance, as well as improved wear resistance.

Description

[Technical field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0153156 filed on November 16, 2020, and Korean Patent Application No. 10-2021-0088035 filed on July 5, 2021, and all contents disclosed in the documents of said Korean patent applications are incorporated as part of this specification.

[0002] The present invention relates to a modified conjugated diene-based polymer having a well-balanced excellent wet skid resistance and running resistance and improved abrasion resistance, and to a rubber composition containing the same. [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 running resistance, excellent abrasion resistance and tensile properties, as well as adjustment stability, as typified by wet skid resistance.

[0004] In order to reduce the running resistance of a tire, there is a method of reducing the hysteresis loss of vulcanized rubber, and the evaluation indexes of such vulcanized rubber are the resilience, tan δ, Goodrich heat generation, etc. at 50° C. to 80° C. In other words, a rubber material having high 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 adjusted as desired, 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, 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] 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 modifying agents to introduce functional groups to the ends. For example, U.S. Patent No. 4,397,994 presents a technique in which active anions at the chain ends of a polymer obtained by polymerizing styrene-butadiene in a non-polar solvent using an alkyllithium, which is a monofunctional initiator, are bonded using a bonding agent such as a tin compound.

[0007] In addition, when the solution-polymerized SBR is used as a rubber material, the physical properties required for tires, such as rolling resistance, can be adjusted by increasing the vinyl content in the SBR, but if the vinyl content is high, braking performance and abrasion resistance are disadvantageous. Therefore, the styrene content in the SBR must be maintained at a certain level or higher, but in this case, there is a problem that the effects that can be obtained from a high vinyl content are not realized.

[0008] Due to these problems, attempts have been made to improve rolling resistance and wet skid resistance in a balanced manner by using a block copolymer SBR containing two block copolymer units having gradients in the styrene and vinyl contents as a solution-polymerized SBR. However, the improvements have been only slight, and when an SBR with a low glass transition temperature is used to improve abrasion resistance, wet skid resistance tends to deteriorate.

[0009] Therefore, there is a need to develop a polymer that can simultaneously improve wet skid resistance and abrasion resistance while still satisfying the product requirements for tensile properties and fuel economy. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] US4,397,994A Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention has been made to solve the above-mentioned problems of the conventional art, and has an object to provide a modified conjugated diene-based polymer having a specific range of difference between the onset temperature and the end temperature of the glass transition temperature by controlling the microstructure of the polymer, in order to realize a tire having a well-balanced improved property of wet skid resistance and abrasion resistance while maintaining excellent tensile properties and fuel economy properties.

[0012] Another object of the present invention is to provide a rubber composition containing the modified conjugated diene polymer. [Means for solving the problem]

[0013] According to one embodiment of the present invention for solving the above problems, the present invention provides a polymerizable composition comprising a repeating unit derived from a conjugated diene monomer and a functional group derived from a modifier, and having a glass transition onset temperature (T g-on ) and the glass transition end temperature (offset, T g-off The present invention provides a modified conjugated diene-based polymer having a temperature difference of 10° C. or more and 30° C. or less.

[0014] The present invention also provides a rubber composition comprising the modified conjugated diene-based polymer and a filler. Effect of the Invention

[0015] The modified conjugated diene-based polymer according to the present invention has an effect of having a low glass transition temperature, but excellent in balanced wet skid resistance and running resistance, and improved abrasion resistance, by controlling the difference between the glass transition start temperature and the end temperature within a specific range through control of the polymer microstructure.

[0016] In addition, the modified conjugated diene-based polymer according to the present invention can achieve excellent abrasion resistance and wet skid resistance by controlling the microstructure, and further, can achieve excellent processability, fuel economy characteristics, and tensile properties by introducing a modifier and adjusting the branching degree. [Brief description of the drawings]

[0017] The following drawings attached to this specification illustrate specific embodiments of the present invention and, together with the above-mentioned content of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited only to the matters described in the drawings.

[0018] [Figure 1]1 is an example of a tan δ graph according to temperature derived from dynamic viscoelastic analysis using an Advanced Rheometric Expansion System (ARES). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The present invention will now be described in more detail so that the present invention may be easily understood. 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.

[0020] Definition of Terms As used herein, the term "polymer" refers to a polymeric compound prepared by polymerizing monomers, whether of the same or different types. The general term polymer thus encompasses the term homopolymer, which is commonly used to refer to a polymer prepared from one type of monomer, and the term copolymer, as defined below.

[0021] As used herein, the term "copolymer" refers to a polymer made by polymerization of at least two different monomers. Thus, the general term copolymer includes two-member copolymers, which are commonly used to refer to polymers made from two different monomers, and polymers made from more than two different monomers.

[0022] As used herein, the term "1,2-vinyl bond content" refers to the mass (or weight) percentage of butadiene contained in the 1,2-positions in the polymer chain of a polymer, based on the portion derived from a conjugated diene monomer (such as butadiene) in the polymer (the total amount of polymerized butadiene).

[0023] As used herein, the term "styrene bond content" refers to the mass (or weight) percentage of styrene contained in the polymer chain of a polymer that is derived from an aromatic vinyl monomer (such as styrene) in the polymer. In this specification, the term "room temperature" means a temperature in its natural state without heating or cooling, and is a temperature of 20±5°C.

[0024] As used herein, the term "substituted" may mean that hydrogen of a functional group, an atomic group, or a compound is replaced with a specific substituent. When 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, and when multiple substituents are present, each substituent may be the same as or different from each other.

[0025] As used herein, the term "alkyl group" means a monovalent aliphatic saturated hydrocarbon group, and can be meant to include any of straight-chain alkyl groups such as methyl, ethyl, propyl, and butyl; branched alkyl groups such as isopropyl, sec-butyl, tert-butyl, and neo-pentyl; and cyclic saturated hydrocarbons, or cyclic unsaturated hydrocarbons containing one or more unsaturated bonds.

[0026] As used herein, the term "alkylene group" may mean a divalent aliphatic saturated hydrocarbon such as methylene, ethylene, propylene, and butylene. As used herein, the term "cycloalkyl group" may mean a cyclic saturated hydrocarbon.

[0027] As used herein, the term "aryl group" refers to an aromatic hydrocarbon and can be intended to include either a monocyclic aromatic hydrocarbon formed with one ring, or a polycyclic aromatic hydrocarbon formed with two or more linked rings.

[0028] As used herein, the term "aralkyl group (aralkyl)", also known as aralkyl, may refer to a combination of an alkyl group and an aryl group formed by replacing a hydrogen atom bonded to a carbon atom constituting an alkyl group with an aryl group.

[0029] As used herein, the term "single bond" may refer to a single covalent bond itself, without another atom or molecular group involved. As used herein, the terms "derived unit," "derived repeating unit," and "derived functional group" can refer to a component or structure originating from a certain substance, or the substance itself.

[0030] In this specification, the terms "comprise", "have" and their derivatives are not intended to exclude the presence of any additional components, steps or procedures, whether they are specifically disclosed or not. To avoid any uncertainty, all compositions claimed by the use of the term "comprise" may include any additional additives, adjuvants or compounds, whether polymeric or otherwise, unless stated to the contrary. In contrast, the term "consisting essentially of" excludes from the scope of any consecutive description any other components, steps or procedures, except those that are not essential for operability. The term "consisting of" excludes any components, steps or procedures not specifically stated or listed.

[0031] Measurement method and conditions In this specification, the "1,2-vinyl bond content" and "styrene bond content" are values ​​measured and analyzed using a Varian VNMRS 500 MHz NMR to measure the vinyl and styrene contents in polymer units. In the NMR measurement, 1,1,2,2-tetrachloroethane was used as the solvent, and the solvent peak was calculated at 6.0 ppm, with 7.2 to 6.9 ppm being random styrene, 6.9 to 6.2 ppm being block styrene, 5.8 to 5.1 ppm being 1,4-vinyl and 1,2-vinyl, and 5.1 to 4.5 ppm being 1,2-vinyl peaks, and the 1,2-vinyl bond content and styrene bond content in the entire polymer were calculated and measured, respectively.

[0032] In this specification, "weight average molecular weight (Mw)", "molecular weight distribution (MWD)", and "unimodal properties" are obtained by measuring the weight average molecular weight (Mw) and number average molecular weight (Mn) under the following conditions using a GPC (gel permeation chromatograph) (PL GPC220, Agilent Technologies) to obtain a molecular weight distribution curve. The molecular weight distributions (PDI, MWD, Mw / Mn) were calculated from the measured molecular weights.

[0033] -Column: Two PLgel Olexis (Polymer Laboratories) columns and one PLgel mixed-C (Polymer Laboratories) column were used in combination. -Solvent: 2% by weight of amine compound mixed in tetrahydrofuran -Flow rate: 1ml / min -Sample concentration: 1-2mg / ml (diluted in THF) -Injection volume: 100μL -Column temperature: 40℃ -Detector: Refractive index -Standard: Polystyrene (corrected by a cubic function)

[0034] In this specification, the "glass transition temperature (Tg)" refers to a differential scanning calorimetry curve (DSC curve) recorded in accordance with ISO 22768:2006 using a differential scanning calorimetry (DSCQ100, manufactured by TA) while heating from -100°C at 10°C / min under a nitrogen flow of 50 ml / min, and the peak top (inflection point) of the DSC differential curve is taken as the glass transition temperature.

[0035] In this specification, the term "glass transition onset temperature (T g-on )" and "Glass transition end temperature (offset, T g-off In accordance with ISO 22768:2006, a differential scanning calorimetry curve (DSC curve) is recorded while heating from -100°C at 10°C / min in a nitrogen flow of 50 ml / min. The temperature at which the glass transition begins on this curve is the glass transition onset temperature, and the temperature at which the glass transition ends is the glass transition end temperature.

[0036] In this specification, the "tan δ peak" refers to a peak that appears in a tan δ graph as a function of temperature derived from dynamic viscoelastic analysis using an Advanced Rheometric Expansion System (ARES), and is measured using a dynamic mechanical analyzer (TA, ARES-G2) in a torsional mode under conditions of a frequency of 10 Hz, a strain of 0.5%, and a heating rate of 5°C / min.

[0037] In this specification, the "Si content" is measured by an ICP analysis method using an inductively coupled plasma optical emission spectrometer (ICP-OES; Optima 7300DV). Using the inductively coupled plasma optical emission spectrometer, about 0.7 g of a sample was placed in a platinum crucible, about 1 mL of concentrated sulfuric acid (98% by weight, electronic grade) was added, and the sample was heated at 300°C for 3 hours. The sample was then ashed in an electric furnace (Thermo Scientific, Lindberg Blue M) using the following program of steps 1 to 3, and then:

[0038] 1) Step 1: initial temp 0℃, rate(temp / hr) 180℃ / hr, temp(holdtime) 180℃(1hr); 2) Step 2: initial temp 180℃, rate(temp / hr) 85℃ / hr, temp(holdtime) 370℃(2hr); 3) Step 3: initial temp 370℃, rate(temp / hr) 47℃ / hr, temp(holdtime) 510℃(3hr);

[0039] 1 mL of concentrated nitric acid (48 wt%) and 20 μL of concentrated hydrofluoric acid (50 wt%) were added to the residue, and the platinum crucible was sealed and shaken for more than 30 minutes. Then, 1 mL of boric acid was added to the sample and stored at 0°C for more than 2 hours. The sample was then diluted with 30 mL of ultrapure water, incinerated, and measured.

[0040] In the present invention, the "N content" may be measured by the NSX analysis method, and the NSX analysis method may be measured using an ultratrace nitrogen quantitative analyzer (NSX-2100H). Specifically, the ultratrace nitrogen quantitative analyzer (Auto sampler, Horizontal furnace, PMT & Nitrogen detector) was turned on, and the carrier gas flow rates were set to Ar 250 ml / min, O2 350 ml / min, and ozonizer 300 ml / min, and the heater was set to 800°C, and the analyzer was stabilized by waiting for about 3 hours. After the analyzer was stabilized, a nitrogen standard (AccuStandard S-22750-01-5ml) was used to create calibration curves with calibration curve ranges of 5 ppm, 10 ppm, 50 ppm, 100 ppm, and 500 ppm, and the area corresponding to each concentration was obtained, and then a straight line was created using the ratio of the area to the concentration. Then, the ceramic boat containing 20 mg of sample was placed in the autosampler of the analyzer and measured to obtain the area. The nitrogen atom content was calculated using the obtained sample area and the calibration curve.

[0041] In this case, the sample used in the above-mentioned NSX analysis method may be a modified conjugated diene polymer sample that is placed in hot water heated with steam and stirred to remove the solvent, and may be a sample from which the residual monomer and the residual modifier have been removed. In addition, if oil has been added to the above-mentioned sample, the sample may be a sample from which the oil has been extracted (removed).

[0042] Modified conjugated diene polymer The present invention provides a modified conjugated diene-based polymer having a difference between its glass transition onset temperature and glass transition end temperature in a specific range by controlling a microstructure that can realize a tire having balanced and improved wet skid resistance and abrasion resistance while maintaining excellent tensile properties and running resistance (fuel economy characteristics).

[0043] The modified conjugated diene polymer according to one embodiment of the present invention contains a repeating unit derived from a conjugated diene monomer and a functional group derived from a modifier, and has a glass transition onset temperature (T g-on ) and the glass transition end temperature (offset, T g-off ) is 10°C or more and 30°C or less.

[0044] According to one embodiment of the present invention, the modified conjugated diene-based polymer realizes a polymer with a specific microstructure by applying a characteristic production method described later, and thereby the difference between the glass transition onset temperature and the glass transition end temperature of the polymer is controlled to 10°C or more and 30°C or less, and the polymer has excellent tensile properties and running resistance, and has excellent wet skid resistance and abrasion resistance in a balanced manner.

[0045] Glass transition onset and end temperatures of polymers According to one embodiment of the present invention, the modified conjugated diene copolymer has a glass transition onset temperature (T g-on ) and the glass transition end temperature (offset, T g-off ) is between 10°C and 30°C.

[0046] In general, in the case of modified polymers produced by polymerization and not having controlled microstructures, the glass transition onset temperature and glass transition end temperature are substantially the same as the glass transition temperature and are within a range of less than ±10° C. from the glass transition temperature, so the difference between the onset temperature and end temperature is not more than 10° C. In this case, the abrasion resistance properties that can be expected to be improved due to the low glass transition temperature can be obtained, but there is a problem that the physical properties of wet skid resistance are deteriorated, and when a polymer with a high glass transition temperature is used, the opposite phenomenon occurs, and it is difficult to easily control the abrasion resistance and wet skid resistance by structural modification of the modifier, the type of functional group, control of the branching degree, etc.

[0047] However, since the modified conjugated diene-based polymer according to one embodiment of the present invention is produced by a production method that controls the microstructure of the polymer, even if it has the same glass transition temperature as existing modified conjugated diene-based polymers, the difference between the glass transition onset temperature and the glass transition end temperature can be controlled within a specific range, thereby achieving the effect of simultaneously increasing wet skid resistance and abrasion resistance.

[0048] In this case, if the difference between the glass transition onset temperature and the glass transition end temperature is less than 10° C., it is impossible to realize the effect of simultaneously improving wet skid resistance and abrasion resistance, and if the difference between the glass transition onset temperature and the glass transition end temperature is greater than 30° C., problems of reduced processability and reduced tensile properties may occur. Therefore, it is necessary to control the difference between the glass transition onset temperature and the glass transition end temperature to be 10° C. or more and 30° C. or less, and in order to optimally realize the above-mentioned effects, it is preferable to set the difference to be 15° C. or more and 30° C. or less.

[0049] Dynamic viscoelastic behavior of polymers According to one embodiment of the present invention, the modified conjugated diene-based polymer satisfies the above-mentioned difference between the glass transition onset temperature and the glass transition end temperature, and may have a full width at half maximum (FWHM) value of a tan δ peak appearing in a temperature range of -100°C to 100°C in a tan δ graph according to temperature derived from dynamic viscoelasticity analysis using an ARES (Advanced Rheometric Expansion System) of 20°C or more.

[0050] In general, in the case of polymers produced by polymerization methods and not having a controlled microstructure, the tan δ peak appears more than once or the peak width is very narrow, and the peak width is not wide. This may be related to the glass transition temperature, but in the case of block copolymers, where the units in the polymer are separated and the difference in glass transition temperature between the blocks is large, the tan δ peak width is narrow and more than two peaks may appear. In addition, in the case of random copolymers, if the vinyl content or styrene content in the final polymer is only adjusted without precisely controlling the microstructure, the peak width generally appears very narrow.

[0051] In this case, the glass transition temperature may be the same for both the block copolymer and the random copolymer, but there is a large difference in wet skid resistance. In order to solve this problem, there are efforts to improve wet skid resistance while accepting changes in glass transition temperature. However, when the glass transition temperature changes, the abrasion resistance changes, and there is a problem that the basic physical properties of the polymer are different, so it remains a challenge to realize a polymer with improved performance. That is, it is difficult to balance abrasion resistance and wet skid resistance, and these two properties tend not to be improved simultaneously through a modification process, so it remains an even more difficult challenge to solve. However, the conjugated diene-based polymer according to one embodiment of the present invention has a unique tan δ peak even if it has the same glass transition temperature as the existing modified conjugated diene-based polymer, in that it is produced by a production method that controls the microstructure of the polymer, and it is possible to realize the effect of simultaneously increasing wet skid resistance and abrasion resistance.

[0052] In this case, the tan δ peak appears in a temperature range of −100° C. to 100° C. in a tan δ graph according to temperature derived from dynamic viscoelasticity analysis by ARES (Advanced Rheometric Expansion System), and the full width at half maximum of the tan δ peak is 25° C. or more. The number of tan δ peaks appearing in the temperature range may usually be one, but may be two or more. When two or more peaks appear, this may mean that the full width at half maximum of one of the multiple peaks is 25° C. or more.

[0053] The full width at half maximum of the tan δ peak may be 25° C. or more, and preferably 30° C. or more. The full width at half maximum may be up to 80° C., and preferably 70° C. or less. As another example, the full width at half maximum of the tan δ peak may be 30° C. or more and 80° C. or less, or 35° C. or more and 60° C. or less. If the full width at half maximum is less than 25° C., a problem occurs in which the wet skid resistance is significantly reduced at the same glass transition temperature, and if the full width at half maximum of the peak is greater than 80° C., it is unlikely to be realized, but even if it is realized, it inevitably involves problems such as phase separation or increased hysteresis at high temperatures, which may cause a problem of poor fuel economy.

[0054] The tan δ peak may appear at −100° C. to 100° C., preferably −80° C. to 20° C., and more preferably −70° C. to 0° C. When the peak appears in the above range, a further advantageous effect in terms of abrasion resistance can be expected.

[0055] The dynamic viscoelasticity analysis using the ARES was carried out by using a dynamic mechanical analyzer (TA, ARES-G2) to measure tan δ according to temperature in the temperature range of -100°C to 100°C in a torsional mode at a frequency of 10 Hz, a deformation rate (Strain) of 0.5%, and a heating rate of 5°C / min. The graph derived at this time shows the tan δ value against temperature.

[0056] Repeating units derived from monomers According to one embodiment of the present invention, the modified conjugated diene polymer has a repeating unit derived from a conjugated diene monomer as a main unit, and the conjugated diene monomer may be, for example, at least one 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).

[0057] In addition, the conjugated diene polymer may further include an aromatic vinyl monomer and a repeating unit derived therefrom in addition to the conjugated diene monomer. The aromatic vinyl monomer may be, for example, at least one selected from the group consisting of styrene, α-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4-(p-methylphenyl)styrene, 1-vinyl-5-hexylnaphthalene, 3-(2-pyrrolidino ethyl)styrene, 4-(2-pyrrolidino ethyl)styrene, and 3-(2-pyrrolidino-1-methyl ethyl)-α-methylstyrene.

[0058] As another example, the conjugated diene polymer may be a copolymer further including a repeating unit derived from a diene monomer having 1 to 10 carbon atoms in addition to the repeating unit derived from the conjugated diene monomer. The repeating unit derived from the diene monomer may be a repeating unit derived from a diene monomer different from the conjugated diene monomer, and the diene monomer different from the conjugated diene monomer may be, for example, 1,2-butadiene. When the conjugated diene polymer is a copolymer further including a diene monomer, the conjugated diene polymer may include the repeating unit derived from the diene monomer in an amount of more than 0% by weight to 1% by weight, more than 0% by weight to 0.1% by weight, more than 0% by weight to 0.01% by weight, or more than 0% by weight to 0.001% by weight. Within this range, there is an effect of preventing the formation of gel.

[0059] According to one embodiment of the present invention, when the conjugated diene polymer chain contains two or more monomers, it may have an intermediate chain structure between a random copolymer and a block copolymer, in which case it is easy to control the microstructure, and therefore it has an effect of having an excellent balance between each physical property. The random copolymer may mean a copolymer in which repeating units constituting the copolymer are randomly arranged.

[0060] Glass transition temperature of polymers According to one embodiment of the present invention, the modified conjugated diene-based polymer may have a glass transition temperature of −100° C. to 20° C. The glass transition temperature is a value that varies depending on the microstructure of the polymer, but in order to improve the abrasion resistance, it is preferable to produce the polymer so that the glass transition temperature satisfies the above range, and the glass transition temperature may be more preferably −100° C. to 0° C., even more preferably −90° C. to −10° C., and even more preferably −80° C. to −20° C.

[0061] The glass transition temperature may be variably adjusted depending on the bonding method (1,2-bond or 1,4-bond) of the conjugated diene monomer in the polymer unit, the presence or absence of a repeating unit derived from an aromatic vinyl monomer, the content of the repeating unit derived from an aromatic vinyl monomer, and the microstructure (1,2-vinyl bond content and styrene bond content) in each unit depending on the polymerization method and polymerization conditions.

[0062] For example, the conjugated diene polymer may contain 0% by weight to 50% by weight, specifically 0% by weight to 45% by weight, preferably more than 0% by weight to 30% by weight or less of repeating units derived from aromatic vinyl monomers. Here, containing 0% by weight of repeating units derived from aromatic vinyl monomers means that the polymer does not contain repeating units derived from aromatic vinyl monomers and is composed only of conjugated diene monomers. In addition, the 1,2-vinyl bond content may be 10 parts by weight to 80 parts by weight, preferably 20 parts by weight to 60 parts by weight, more preferably 20 parts by weight to 50 parts by weight, based on 100 parts by weight of the modified conjugated diene polymer. When the microstructure is controlled in this way, it is expected to have excellent tensile properties and fuel efficiency characteristics, and a balanced improvement in wear resistance and wet skid resistance.

[0063] Silicon and nitrogen content of polymers Meanwhile, the modified conjugated diene polymer according to one embodiment of the present invention may have a Si and N content of 50 ppm or more, or 50 ppm to 1000 ppm, based on the total weight of the polymer, and preferably 100 ppm or more, or 150 ppm or more, and preferably 700 ppm or less, preferably 500 ppm or less, in the lower limit. Within this range, the rubber composition containing the modified conjugated diene polymer has excellent mechanical properties such as tensile properties and viscoelastic properties. Meanwhile, the Si and N may be derived from a compound having a modified functional group, such as a modifying agent, a modified initiator, or a modified monomer, which will be described later, by introducing the compound.

[0064] Denaturing Agent According to one embodiment of the present invention, the modified conjugated diene-based polymer contains a functional group derived from a modifier, and the modifier is used to modify the terminal of the polymer, and a specific example of the silica affinity modifier may be an alkoxysilane-based modifier. The silica affinity modifier means a modifier containing a silica affinity functional group in a compound used as a modifier, and the silica affinity functional group may mean a functional group that has excellent affinity with a filler, particularly a silica-based filler, and can interact with the silica-based filler and the functional group derived from the modifier.

[0065] The modifier may be, for example, an alkoxysilane-based modifier, and may be, for example, an alkoxysilane-based compound containing one or more heteroatoms such as nitrogen, oxygen, or sulfur. When the alkoxysilane-based compound is used as the modifier, one end of the activated polymer may be modified to a form in which the activated polymer is bonded to a silyl group through a substitution reaction between an anion active site located at one end of the activated polymer and an alkoxy group of the alkoxysilane-based compound, and thus the affinity of the modified conjugated diene-based polymer with inorganic fillers and the like can be improved from the functional group derived from the modifier present at one end of the polymer unit. Thus, there is an effect that the viscoelasticity of the rubber composition containing the modified conjugated diene-based polymer is further improved. Furthermore, when the alkoxysilane-based compound contains a nitrogen atom, in addition to the effect derived from the silyl group, an additional effect of increasing physical properties derived from the nitrogen atom can be expected. In order to optimally realize such an effect, it is preferable to apply an alkoxysilane-based compound containing an N-containing functional group.

[0066] According to one embodiment of the present invention, the denaturant may include a compound represented by the following Formula 1:

[0067] [ka]

[0068] In the above formula 1, R 1 may be a single bond or an alkylene group having 1 to 10 carbon atoms; R 2 and R 3 may each independently be an alkyl group having 1 to 10 carbon atoms; R 4 may be hydrogen, an alkyl group having 1 to 10 carbon atoms, a mono-, di-, or tri-substituted alkylsilyl group substituted with an alkyl group having 1 to 10 carbon atoms, or a heterocyclic group having 2 to 10 carbon atoms; R 21 is a single bond, an alkylene group having 1 to 10 carbon atoms, or -[R 42 O] j - may be R 42may be an alkylene group having 1 to 10 carbon atoms, a and m may each independently be an integer selected from 1 to 3, n may be an integer of 0, 1, or 2, and j may be an integer selected from 1 to 30.

[0069] As a specific example, in the above Chemical Formula 1, R 1 may be a single bond or an alkylene group having 1 to 5 carbon atoms; R 2 and R 3 may each independently be hydrogen or an alkyl group having 1 to 5 carbon atoms; R 4 may be hydrogen, an alkyl group having 1 to 5 carbon atoms, a trialkylsilyl group substituted with an alkyl group having 1 to 5 carbon atoms, or a heterocyclic group having 2 to 5 carbon atoms; R 21 is a single bond, an alkylene group having 1 to 5 carbon atoms, or -[R 42 O] j - may be R 42 may be an alkylene group having 1 to 5 carbon atoms, a may be an integer of 2 or 3, m may be an integer selected from 1 to 3, n may be an integer of 0, 1, or 2, in which case m+n=3, and j may be an integer selected from 1 to 10.

[0070] In the above formula 1, R 4 is a heterocyclic group, the heterocyclic group may be unsubstituted or substituted with a tri-substituted alkoxysilyl group, and when the heterocyclic group is substituted with a tri-substituted alkoxysilyl group, the tri-substituted alkoxysilyl group may be linked to the heterocyclic group and substituted by an alkylene group having 1 to 10 carbon atoms, and the tri-substituted alkoxysilyl group may mean an alkoxysilyl group substituted with an alkoxy group having 1 to 10 carbon atoms.

[0071] More specifically, the compound represented by Chemical Formula 1 is N,N-bis(3-(dimethoxy(methyl)silyl)propyl)-methyl-1-amine, N,N-bis(3-(diethoxy(methyl)silyl)propyl)-methyl-1-amine, N,N-bis(3-(trimethoxysilyl)propyl) -methyl-1-amine, N,N-bis(3-(trimethoxysilyl)propyl)-methyl-1-amine, N,N-bis(3-(triethoxysilyl)propyl)-methyl-1-amine, N,N-diethyl-3-(trimethoxysilyl)propan-1-amine, N,N-diethyl-3-(trimethoxysilyl)propan-1-amine N,N-diethyl-3-(triethoxysilyl)propan-1-amine, tri(trimethoxysilyl)amine, tri(3-(trimethoxysilyl)propyl)amine, N,N-bis(3-(diethoxy(methyl)silyl)propyl)-1,1,1-trimethylsilanamine )propyl)-1,1,1-trimethylsilanamine), N,N-bis(3-(1H-imidazol-1-yl)propyl)-(triethoxysilyl)methan-1-amine), N-(3-(1H-1,2,4-triazol-1-yl)propyl)-3-(trimethoxysilyl)-N-(3-(trimethoxysilyl)propyl)propan-1-amine4-triazole-1-yl)propyl)-3-(trimethoxysilyl)-N-(trimethoxysilyl)propyl)propan-1-amine), 3-(trimethoxysilyl)-N-(3-trimethoxysilyl)propyl)-N-(3-(1-(3-(trimethoxysilyl)propyl)-1H-1,2,4-triazole-3-yl)propyl)propan-1-amine -(1-(3-(trimethoxysilyl)propyl)-1H-1,2,4-triazol-3-yl)propyl)propan-1-amine), N,N-bis(2-(2-methoxyethoxy)ethyl)-3-(triethoxysilyl)propan-1-amine, N,N-bis(3-(triethoxysilyl)propyl)-2,5,8,11,14-pentaoxahexaamine N,N-bis(3-(triethoxysilyl)propyl)-2,5,8,11,14-pentaoxahexadecan-16-amine, N-(2,5,8,11,14-pentaoxahexadecan-16-yl)-N-(3-(triethoxysilyl)propyl)-2,5,8,11,14-pentaoxahexadecan-16-amine It may be one selected from the group consisting of N-(3,6,9,12-tetraoxahexadecyl)-N-(3-(triethoxysilyl)propyl)-3,6,9,12-tetraoxahexadecan-1-amine.

[0072] In another example, the denaturant may include a compound represented by the following Chemical Formula 2:

[0073] [ka]

[0074] In the above formula 2, R 5 , R 6 , and R 9 may each independently be an alkylene group having 1 to 10 carbon atoms; R 7 , R 8 , R 10 , and R 11 may each independently be an alkyl group having 1 to 10 carbon atoms; R 12 may be hydrogen or an alkyl group having 1 to 10 carbon atoms; b and c are each independently 0, 1, 2, or 3, and may satisfy b+c≧1; A is [ka] In this case, R 13 , R 14 , R 15 , and R 16 may each independently be hydrogen or an alkyl group having 1 to 10 carbon atoms.

[0075] As a specific example, the compound represented by Chemical Formula 2 may be one selected from the group consisting of N-(3-(1H-imidazol-1-yl)propyl)-3-(triethoxysilyl)-N-(3-(triethoxysilyl)propyl)propan-1-amine and 3-(4,5-dihydro-1H-imidazol-1-yl)-N,N-bis(3-(triethoxysilyl)propyl)propan-1-amine.

[0076] In another example, the denaturant may include a compound represented by the following Formula 3:

[0077] [ka]

[0078] In the above Chemical Formula 3, A 1 and A 2 may each independently be a divalent hydrocarbon group having 1 to 20 carbon atoms which may or may not contain an oxygen atom, R 17 ~R 20 may each independently be a monovalent hydrocarbon group having 1 to 20 carbon atoms; L 1 ~L 4 are each independently a mono-, di-, or tri-substituted alkylsilyl group substituted with an alkyl group having 1 to 10 carbon atoms, or a monovalent hydrocarbon group having 1 to 20 carbon atoms; 1 and L 2 And, L 3 and L 4 may be linked together to form a ring having 1 to 5 carbon atoms, L 1 and L 2 And, L 3 and L 4are linked together to form a ring, the ring formed may contain 1 to 3 heteroatoms of one or more types selected from the group consisting of N, O, and S.

[0079] As a specific example, in the above Chemical Formula 3, 1 and A 2 may each independently be an alkylene group having 1 to 10 carbon atoms; R 17 ~R 20 may each independently be an alkyl group having 1 to 10 carbon atoms; L 1 ~L 4 each independently represents a trialkylsilyl group substituted with an alkyl group having 1 to 5 carbon atoms, an alkyl group having 1 to 10 carbon atoms, or L 1 and L 2 And, L 3 and L 4 may be linked together to form a ring having 1 to 3 carbon atoms, L 1 and L 2 And, L 3 and L 4 are linked together to form a ring, the ring formed may contain 1 to 3 heteroatoms of one or more types selected from the group consisting of N, O, and S.

[0080] More specifically, the compound represented by Chemical Formula 3 is 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-dimethylpropan-1-amine), 3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(N,N-dimethylpropan-1-amine), isiloxane-1,3-diyl)bis(N,N-dimethylpropan-1-amine)), 3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,N-dimethylpropan-1-amine)), 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine) 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine)), 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-dipropylpropan-1-amine)), 3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-di 3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine), 3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine),3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(N,N-dipropylpropan-1-amine) pylpropan-1-amine), 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-diethylmethan-1-amine), 3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(N,N-diethylmethan-1-amine) e-1,3-diyl)bis(N,N-diethylmethan-1-amine), 3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,N-diethylmethan-1-amine), 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-dimethylmethan-1-amine) 3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-dimethylmethan-1-amine), 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-dipropylmethan-1-amine), 3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,N-dipropylmethan-1-amine), 3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,N-dipropylmethan-1-amine), 3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(N,N-dimethylmethan-1-amine), 3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(N,N-dipropylmethan-1-amine N,N'-((1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(propan-3,1-diyl))bis(1,1,1-trimethyl-N-(trimethylsilyl)silanamine)), N,N'-((1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(propan-3,1-diyl))bis(1,1,1-trimethyl-N-(trimethylsilyl)silanamine)), N,N'-((1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(propan-3,1-diyl))bis(1,1,1-trimethyl-N-(trimethylsilyl)silanamine)), N,N'-((1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(propan-3,1-diyl))bis(1,1,1-trimethyl-N-(trimethylsilyl)silanamine) (N,N'-((1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(propan-3,1-diyl))bis(1,1,1-trimethyl-N-(trimethylsilyl)silanamine)), N,N'-((1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(propane-3,1-diyl))bis(1,1,1-trimethyl-N-phenylsilanamine) (N,N'-((1,1,3,3-tetra methoxydisiloxane-1,3-diyl)bis(propan-3,1-diyl))bis(1,1,1-trimethyl-N-phenylsilanamine) 1,3-bis(3-(1H-imidazol-1-yl)propan-2-yl))bis(1,1,1-trimethyl-N-phenylsilanamine), N,N'-((1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(propan-3,1-diyl))bis(1,1,1-trimethyl-N-phenylsilanamine), 1,3-bis(3-(1H-imidazol-1-yl)propan-2-yl))bis(1,1,1-trimethyl-N-phenylsilanamine) 1,3-bis(3-(1H-imidazol-1-yl)propyl)-1,1,3,3-tetramethoxydisiloxane, 1,3-bis(3-(1H-imidazol-1-yl)propyl)-1,1,3,3-tetraethoxydisiloxane, and 1,3-bis(3-(1H-imidazol-1-yl)propyl)-1,It may be one selected from the group consisting of 1,3,3-tetrapropoxydisiloxane (1,3-bis(3-(1H-imidazol-1-yl)propyl)-1,1,3,3-tetrapropoxydisiloxane).

[0081] In another example, the denaturant may include a compound represented by the following Formula 4:

[0082] [ka]

[0083] In the above Chemical Formula 4, R 22 and R 23 each independently represents an alkylene group having 1 to 20 carbon atoms, or -R 28 [OR 29 ] f - and R 24 ~R 27 may each independently be an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms; R 28 and R 29 may each independently be an alkylene group having 1 to 20 carbon atoms; R 47 and R 48 may each independently be a divalent hydrocarbon group having 1 to 6 carbon atoms, d and e each independently be 0 or an integer selected from 1 to 3, in which case d+e is an integer of 1 or more, and f may be an integer of 1 to 30.

[0084] Specifically, in the above Chemical Formula 4, R 22 and R 23 each independently represents an alkylene group having 1 to 10 carbon atoms, or -R 28 [OR 29 ] f - may be R 24 ~R 27 may each independently be an alkyl group having 1 to 10 carbon atoms; R 28 and R 29may each independently be an alkylene group having 1 to 10 carbon atoms, d and e each independently be 0 or an integer selected from 1 to 3, in which case d+e may be an integer of 1 or more, and f may be an integer selected from 1 to 30.

[0085] More specifically, the compound represented by the formula 4 may be a compound represented by the following formula 4a, 4b, or 4c.

[0086] [ka]

[0087] [ka]

[0088] [ka]

[0089] In the above Chemical Formula 4a, Chemical Formula 4b, and Chemical Formula 4c, R 22 ~R 27 , d, and e are as described above.

[0090] More specifically, the compound represented by the formula 4 is 1,4-bis(3-(3-(triethoxysilyl)propoxy)propyl)piperazine, 1,4-bis(3-(triethoxysilyl)propyl)piperazine, 1,4-bis(3-(trimethoxysilyl)propyl)piperazine, 1,4-bis(3-(dimethoxymethylsilyl)propyl)piperazine, 1-(3-(ethoxydimethylsilyl)propyl)-4-(3-(triethoxysilyl)propyl)piperazine, 1-(3 1-(3-(ethoxydimethyl)propyl)-4-(3-(triethoxysilyl)methyl)piperazine, 1-(3-(ethoxydimethyl)methyl)-4-(3-(triethoxysilyl)propyl)piperazine, 1,3-bis(3-(triethoxysilyl)propyl) 1,3-bis(3-(triethoxysilyl)propyl)imidazolidine, 1,3-bis(3-(dimethoxyethylsilyl)propyl)imidazolidine, 1,3-bis(3-(trimethoxysilyl)propyl)hexahydropyrimidine, 1,It may be one selected from the group consisting of 1,3-bis(3-(triethoxysilyl)propyl)hexahydropyrimidine and 1,3-bis(3-(tributoxysilyl)propyl)-1,2,3,4-tetrahydropyrimidine.

[0091] In another example, the denaturant may include a compound represented by the following Formula 5:

[0092] [ka]

[0093] In the above Chemical Formula 5, R 30 may be a monovalent hydrocarbon group having 1 to 30 carbon atoms, R 31 ~R 33 may each independently be an alkylene group having 1 to 10 carbon atoms; R 34 ~R 37 may each independently be an alkyl group having 1 to 10 carbon atoms, and g and h each independently are 0 or an integer selected from 1 to 3, in which case g+h may be an integer of 1 or greater.

[0094] In another example, the denaturant may include a compound represented by the following Formula 6:

[0095] [ka]

[0096] In the above Chemical Formula 6, A 3 and A 4 may each independently be an alkylene group having 1 to 10 carbon atoms; R 38 ~R 41may each independently be an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and i may be an integer selected from 1 to 30.

[0097] As another example, the modifying agent may be 3,4-bis(2-methoxyethoxy)-N-(4-(triethylsilyl)butyl)aniline, N,N-diethyl-3-(7-methyl-3,6,8,11-tetraoxa-7-silatridecan-7-yl)propan-1-amine, 2,4-bis(2-methoxyethoxy)-N-(4-(triethylsilyl)butyl)aniline, N,N-diethyl-3-(7-methyl-3,6,8,11-tetraoxa-7-silatridecan-7-yl)propan-1-amine, 2,4-bis(2-methoxyethoxy)-N-(4-(triethylsilyl)butyl)aniline, The compound may contain one or more selected from the group consisting of 2,4-bis(2-methoxyethoxy)-6-((trimethylsilyl)methyl)-1,3,5-triazine, and 3,14-dimethoxy-3,8,8,13-tetramethyl-2,14-dioxa-7,9-dithia-3,8,13-trisilapentadecane.

[0098] In another example, the denaturant may include a compound represented by the following Formula 7:

[0099] [ka]

[0100] In the above Chemical Formula 7, R 43 , R 45 , and R 46 may each independently be an alkyl group having 1 to 10 carbon atoms; R 44may be an alkylene group having 1 to 10 carbon atoms, and k may be an integer selected from 1 to 4.

[0101] As a more specific example, the compound represented by the formula 7 is 8,8-dibutyl-3,13-dimethoxy-3,13-dimethyl-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane ane), 8,8-dimethyl-3,13-dimethoxy-3,13-dimethyl-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane, 8,8-dibutyl-3,3,13,1 It may be one selected from the group consisting of 3-tetramethoxy-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane (8,8-dibutyl-3,3,13,13-tetramethoxy-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane) and 8-butyl-3,3,13,13-tetramethoxy-8-((3-(trimethoxysilyl)propyl)thio)-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane (8-butyl-3,3,13,13-tetramethoxy-8-((3-(trimethoxysilyl)propyl)thio)-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane).

[0102] In another example, the denaturant may include a compound represented by the following Formula 8:

[0103] [ka]

[0104] In the above Chemical Formula 8, R b2 ~R b4 are each independently an alkylene group having 1 to 10 carbon atoms; R b5 ~R b8 are each independently an alkyl group having 1 to 10 carbon atoms, and R b13 and R b14 are each independently an alkylene group having 1 to 10 carbon atoms; R b15 ~R b18 are each independently an alkyl group having 1 to 10 carbon atoms, and m1, m2, m3, and m4 are each independently an integer of 1 to 3.

[0105] In another example, the denaturant may include a compound represented by the following Formula 9:

[0106] [ka]

[0107] In the above Chemical Formula 9, R e1 and R e2 are each independently an alkylene group having 1 to 10 carbon atoms; R e3 ~R e6 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or -R e7 SiR e8 R e9 R e10 In this case, R e3 ~R e6 At least one of the following is -R e7 SiR e8 R e9 R e10 where R e7 is a single bond or an alkylene group having 1 to 10 carbon atoms, and R e8 ~R e10 are each independently an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, in which case R e8 ~R e10At least one of them is an alkoxy group having 1 to 10 carbon atoms.

[0108] In another example, the denaturant may include a compound represented by the following Formula 10:

[0109] [ka]

[0110] In the above formula 10, X is O or S, and R f1 and R f2 are each independently a single bond or an alkylene group having 1 to 10 carbon atoms, R f3 ~R f8 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, or an aralkyl group having 7 to 14 carbon atoms; p is an integer of 0 or 1; when p is 0, R f1 is an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms.

[0111] In another example, the denaturant may include a compound represented by the following formula 11:

[0112] [ka]

[0113] In the above formula 11, R g1 ~R g4 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or -R g5 SiOR g6 In this case, R g1 ~R g4 At least one of the following is -R g5 SiOR g6 where R g5is a single bond or an alkylene group having 1 to 10 carbon atoms, and R g6 is an alkyl group having 1 to 10 carbon atoms, and Y is C or N. In this case, when Y is N, R g4 does not exist.

[0114] In another example, the denaturant may include a compound represented by the following Formula 12:

[0115] [ka]

[0116] In the above formula 12, R h1 and R h2 are each independently an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms; R h3 is a single bond or an alkylene group having 1 to 10 carbon atoms; A 3 is -Si(R h4 R h5 R h6 ), or -N[Si(R h7 R h8 R h9 )]2, where R h4 ~R h9 are each independently an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms.

[0117] In another example, the denaturant may include a compound represented by the following Formula 13:

[0118] [ka]

[0119] In the above formula 13, R g1 ~R g3 are each independently an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms; R g4 is an alkoxy group having 1 to 10 carbon atoms, and q is an integer of 2 to 100.

[0120] Other characteristics The modified conjugated diene-based polymer according to one embodiment of the present invention may have a shrinkage factor (g') of 0.1 or more, preferably 0.1 or more and 1.0 or less, more specifically 0.3 or more and 0.9 or less, as determined by GPC-light scattering method with a viscosity detector.

[0121] Here, the shrinkage factor (g') obtained by the GPC-light scattering measurement is the ratio of the intrinsic viscosity of a branched polymer to the intrinsic viscosity of a linear polymer having the same absolute molecular weight, and can be used as an index of the branched structure of the branched polymer, i.e., an index of the proportion of branches. For example, as the shrinkage factor decreases, the number of branches of the polymer tends to increase. Therefore, when comparing polymers with the same absolute molecular weight, the shrinkage factor decreases as the number of branches increases, and therefore, can be used as an index of the degree of branching.

[0122] The shrinkage factor was calculated based on the solution viscosity and light scattering method by measuring a chromatogram using a GPC-light scattering measurement device with a viscosity detector. Specifically, the absolute molecular weight and the intrinsic viscosity corresponding to each absolute molecular weight were obtained using a GPC-light scattering measurement device with a light scattering detector and a viscosity detector connected to two columns filled with polystyrene gel, and the intrinsic viscosity of the linear polymer corresponding to the absolute molecular weight was calculated, and the shrinkage factor was calculated as the ratio of the intrinsic viscosity corresponding to each absolute molecular weight. For example, the shrinkage factor was calculated by injecting a sample into a GPC-light scattering measurement device with a light scattering detector and a viscosity detector (Viscotek TDAmax, Malvern Co.), obtaining the absolute molecular weight from the light scattering detector, obtaining the intrinsic viscosity [η] for the absolute molecular weight from the light scattering detector and the viscosity detector, and then calculating the intrinsic viscosity [η]0 of the linear polymer for the absolute molecular weight according to the following mathematical formula 1, and the average value of the ratio of the intrinsic viscosity ([η] / [η]0) corresponding to each absolute molecular weight was shown as the shrinkage factor. In this case, a mixed solution of tetrahydrofuran and N,N,N',N'-tetramethylethylenediamine (prepared by mixing 20 mL of N,N,N',N'-tetramethylethylenediamine with 1 L of tetrahydrofuran) was used as the eluent, and a PL Olexix (Agilent) was used as the column. Measurements were performed under conditions of an oven temperature of 40°C and a THF flow rate of 1.0 mL / min, and the sample was prepared by dissolving 15 mg of polymer in 10 mL of THF.

[0123] [Mathematical formula 1] [η]0=10 -3.883 M 0.771 In the above mathematical formula 1, M is the absolute molecular weight.

[0124] 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. Here, the vinyl content may refer to the content of 1,2-added conjugated diene monomer, not 1,4-added, relative to 100% by weight of a conjugated diene polymer composed of a monomer having a vinyl group and an aromatic vinyl monomer.

[0125] As another example, the modified conjugated diene polymer may have a Mooney stress relaxation ratio of less than 0.7 or from 0.7 to 3.0 measured at 100° C. Specifically, in the case of a branched polymer with a high degree of branching, the Mooney stress relaxation ratio may be less than 0.7, preferably 0.6 or less, more preferably 0.5 or less, and most preferably 0.4 or less, and in the case of a linear polymer with a low degree of branching, the Mooney stress relaxation ratio may be preferably 0.7 to 2.5, and more preferably 0.7 to 2.0.

[0126] Here, the Mooney stress relaxation rate indicates the change in stress that occurs as a response to the same amount of strain, and may be measured using a Mooney viscometer. Specifically, the Mooney stress relaxation rate was obtained by using a Monsanto MV2000E Large Rotor under the conditions of 100°C and a rotor speed of 2±0.02 rpm, leaving the polymer at room temperature (23±5°C) for 30 minutes or more, taking 27±3g and filling the inside of a die cavity, operating a platen to apply torque and measuring the Mooney viscosity, and then measuring the slope of the change in Mooney viscosity that occurs as the torque is released.

[0127] On the other hand, the Mooney stress relaxation rate can be used as an index of the branched structure of the polymer. For example, when comparing polymers with the same Mooney viscosity, the more branches there are, the smaller the Mooney stress relaxation rate becomes, and therefore the Mooney stress relaxation rate can be used as an index of the degree of branching.

[0128] The modified conjugated diene-based polymer according to one embodiment of the present invention may contain a functional group derived from a modified initiator at one end in addition to the functional group derived from the modifying agent, and the modified initiator may be a reaction product of an N-functional group-containing compound and an organometallic compound.

[0129] Specifically, the N-functional group-containing compound may be an aromatic hydrocarbon compound containing an N-functional group including an amino group, an amido group, an amino group, an imidazole group, a pyrimidyl group, or a cyclic amino group, which is substituted or unsubstituted with a substituent, and the substituent may be an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, or an alkoxysilyl group having 1 to 10 carbon atoms.

[0130] According to an embodiment of the present invention, the modified conjugated diene-based polymer may have a weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of 300,000 g / mol to 3,000,000 g / mol, 400,000 g / mol to 2,500,000 g / mol, or 500,000 g / mol to 2,000,000 g / mol. Within this range, the effect of more well-balanced excellent running resistance and wet skid resistance is obtained.

[0131] In addition, the modified conjugated diene-based polymer according to one embodiment of the present invention may be a high molecular weight polymer having a weight average molecular weight of 800,000 g / mol or more, preferably 1,000,000 g / mol or more, thereby realizing a polymer with excellent tensile properties. This can be achieved by controlling the microstructure and extending the polymer chain length when produced by the above-mentioned production method.

[0132] The modified conjugated diene polymer according to one embodiment of the present invention may have a number average molecular weight (Mn) of 1,000 g / mol to 2,000,000 g / mol, 10,000 g / mol to 1,500,000 g / mol, or 100,000 g / mol to 1,200,000 g / mol, and the number average molecular weight may be preferably 400,000 g / mol or more, more preferably 500,000 g / mol or more. The peak top molecular weight (Mp) may be 1,000 g / mol to 3,000,000 g / mol, 10,000 g / mol to 2,000,000 g / mol, or 100,000 g / mol to 2,000,000 g / mol. Within this range, there is an effect of excellent running resistance and wet skid resistance.

[0133] The modified conjugated diene polymer has a unimodal molecular weight distribution curve as determined by gel permeation chromatography (GPC), and the molecular weight distribution may be 1.0 to 3.0, preferably 1.0 to 2.5, more preferably 1.0 to 2.0, and even more preferably 1.0 or more and less than 1.7. The unimodal curve shape and molecular weight distribution can be simultaneously achieved by continuous polymerization, which will be described later.

[0134] In general, continuous polymerization has a wide unimodal molecular weight distribution, resulting in excellent processability but poor tensile and viscoelastic properties, while batch polymerization has a narrow bimodal molecular weight distribution, resulting in poor processability but excellent tensile and viscoelastic properties, resulting in low productivity. However, by applying the production method described below according to one embodiment of the present invention, the molecular weight distribution can be selectively narrowed to the maximum extent possible despite the continuous production, and thus it is easy to control the balance of physical properties between processability and tensile and viscoelastic properties.

[0135] The modified conjugated diene-based polymer according to one embodiment of the present invention must have a Mooney viscosity measured under ASTM D1646 conditions of 40 to 120, and may preferably have a Mooney viscosity of 45 to 100. There are various scales for evaluating processability, but when the Mooney viscosity satisfies the above range, the processability can be considerably excellent.

[0136] As described above, the modified conjugated diene-based polymer according to an embodiment of the present invention is expected to have a balanced improvement in abrasion resistance and wet skid resistance while maintaining excellent tensile properties, fuel economy properties, and processability by specifying a polymer structure so as to have a difference between a glass transition onset temperature and an end temperature by controlling a polymer microstructure such as a styrene bond content and a 1,2-vinyl bond content, and selectively controlling a weight average molecular weight, a shape of a molecular weight distribution curve, a molecular weight distribution, a content of N and Si atoms, and a Mooney viscosity.

[0137] Method for producing modified conjugated diene polymer In order to produce the modified conjugated diene polymer, the present invention provides the following method for producing a modified conjugated diene polymer.

[0138] The method for producing the modified conjugated diene polymer includes a step (S1) of producing an active polymer by polymerizing a conjugated diene monomer, or a conjugated diene monomer and an aromatic vinyl monomer, in the presence of a hydrocarbon solvent, a polymerization initiator, and a polar additive by a continuous production method, and a step (S2) of reacting the active polymer produced in the step (S1) with a modifier, wherein the step (S1) is continuously performed in two or more polymerization reactors, and when the polymerization conversion rate of the first reactor is 70% to 85%, the polymer is transferred to a second reactor, and a polar additive, or a polar additive and a conjugated diene monomer are additionally added to the second reactor. Since the modified conjugated diene polymer and the modifier used in the reaction have been described above, the following description will focus on the preparation method.

[0139] 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.

[0140] The polymerization initiator may be used in an amount of 0.1 to 3.0 equivalents based on 1.0 equivalent of the monomer, preferably 0.1 to 2.0 equivalents, more preferably 0.5 to 1.5 equivalents. In another example, the polymerization initiator 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, 0.1 mmol to 1 mmol, or 0.15 to 0.8 mmol based on 100 g of the total monomer. Here, the total 100 g of the monomer may be a conjugated diene monomer, or may represent the total amount of the conjugated diene monomer and the aromatic vinyl monomer.

[0141] On the other hand, the polymerization initiator may be an organometallic compound, for example, one or more selected from an organolithium compound, an organosodium compound, an organopotassium compound, an organorubidium compound, and an organocesium compound.

[0142] Specifically, the organometallic compound may be at least one selected from the group consisting of 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-naphthyl lithium, n-eicosyl lithium, 4-butylphenyl lithium, 4-tolyl lithium, cyclohexyl lithium, 3,5-di-n-heptylcyclohexyl lithium, 4-cyclopentyl lithium, 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.

[0143] As another example, the polymerization initiator may be a modified initiator, which may be a reaction product of an N-functional compound and the organometallic compound.

[0144] S1 Step According to an embodiment of the present invention, in the preparation method, step (S1) is, for example, a step of performing a polymerization reaction of a conjugated diene monomer or a conjugated diene monomer and an aromatic vinyl monomer by anionic polymerization. As a specific example, it may be living anionic polymerization having an anionic active site at the polymerization end by a growth polymerization reaction by anion. Also, the polymerization in step (S1) 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 by its own reaction heat without adding any heat after adding a polymerization initiator, the temperature-rise polymerization refers to a polymerization method of increasing the temperature by adding any heat after adding the polymerization initiator, and the isothermal polymerization may refer to a polymerization method of maintaining the temperature of the polymer constant by adding heat to increase the heat or removing heat after adding the polymerization initiator.

[0145] According to one embodiment of the present invention, the polymerization in step (S1) may be carried out by further including a diene compound having 1 to 10 carbon atoms in addition to the conjugated diene monomer, and in this case, it is possible to prevent gel formation on the wall of the reactor during long-term operation. The diene compound may be, for example, 1,2-butadiene.

[0146] According to one embodiment of the present invention, the polymerization in the (S1) step is carried out in two or more polymerization reactors, and the polymerization conversion rate in the first polymerization reactor among the polymerization reactors may be 70% to 85%, or 70% to 80%. That is, in the (S1) step, the polymerization is carried out until the polymerization conversion rate in the first polymerization reactor is 70% or more, 70% to 85%, or 70% to 80%.

[0147] Within this range, side reactions occurring as the polymer is formed after the start of the polymerization reaction can be suppressed, and the microstructure of the polymer can be easily controlled during polymerization, so that the full width at half maximum of the tan δ peak in dynamic viscoelastic analysis becomes wider, thereby providing a basis for improving abrasion resistance.

[0148] The polymerization in the first reactor may be carried out at a temperature range of, for example, 80° C. or less, −20° C. to 80° C., 0° C. to 80° C., 0° C. to 70° C., or 10° C. to 70° C. Within this range, the molecular weight distribution of the polymer can be narrowly adjusted, and there is an effect of excellent improvement in physical properties.

[0149] According to one embodiment of the present invention, the step (S1) is carried out in two or more reactors, and after the polymerization is carried out in the first reactor up to the polymerization conversion rate described above, the polymerization is transferred to the second reactor, and a polar additive or a conjugated diene monomer is additionally added to the second reactor.

[0150] In this case, the polar additive or the polar additive or the conjugated diene monomer to be added may be added simultaneously or sequentially, and may be added at a single point within the above-mentioned polymerization conversion range, or may be added in portions at multiple points within the above-mentioned range, or may be added continuously within the above-mentioned range.

[0151] The addition of the polar additive or the polar additive and the conjugated diene monomer can be a means to realize the glass transition temperature characteristic of the polymer produced in addition to controlling the polymerization conversion rate in the first reactor, because the addition of the polar additive can further add power to the polymerization reaction after a certain polymerization conversion rate, causing deformation of the microstructure.

[0152] In particular, the polar additive can control the ratio of 1,2-bonds and 1,4-bonds by controlling the reaction rate when homopolymerizing a conjugated diene monomer, and can easily induce the formation of a random copolymer by correcting the difference in reaction rate between these monomers when copolymerizing a conjugated diene monomer and an aromatic vinyl monomer.

[0153] In this case, the polar additive to be added may be used in an appropriate amount so that the full width at half maximum of the tan δ peak becomes wider. For example, the polar additive to be added may be used in an amount of 0.001 g to 10 g, or 0.01 g to 1.0 g, more preferably 0.02 g to 0.5 g, based on the total 100 g of the monomers used for initiating polymerization.

[0154] In addition, the conjugated diene monomer may be added in an amount of 5 g to 25 g or 5 g to 20 g based on 100 g of the monomer used for initiating polymerization. When the polar additive or the conjugated diene monomer is added in the above amounts, the glass transition temperature of the polymer is easily controlled and can be finely adjusted, and the full width at half maximum of the tan δ peak can be further increased in dynamic viscoelastic analysis.

[0155] The total amount of polar additives used in the polymerization of step (S1) may be 0.001g to 50g, or 0.002g to 1.0g based on a total of 100g of monomers. As another example, the total amount of polar additives used may be more than 0g to 1g, 0.01g to 1g, or 0.1g to 0.9g based on a total of 100g of polymerization initiators. Here, the total amount of polar additives used means the content including the polar additives added additionally.

[0156] The polymerization in the second reactor may be carried out at a temperature range of, for example, 80° C. or less, −20° C. to 80° C., 0° C. to 80° C., 0° C. to 70° C., or 10° C. to 70° C. Within this range, the molecular weight distribution of the polymer can be narrowly adjusted, and there is an effect of excellent improvement in physical properties.

[0157] On the other hand, in controlling the full width at half maximum of the tan δ peak obtained from the dynamic viscoelasticity analysis, the polymerization temperatures in the first and second reactors may also have an effect. In this case, it is preferable to control the polymerization temperature of the second reactor to be equal to or lower than the polymerization temperature of the first reactor, and it is preferable that the polymerization temperature of the second reactor is 60° C. or higher.

[0158] The polar additive may be, for example, one or more selected from the group consisting of tetrahydrofuran, 2,2-di(2-tetrahydrofuryl)propane, diethyl ether, cyclopentyl ether, dipropyl ether, ethylene methyl ether, ethylene glycol dimethyl ether, diethylene glycol, dimethyl ether, tert-butoxyethoxyethane, bis(3-dimethylaminoethyl)ether, (dimethylaminoethyl)ethyl ether, trimethylamine, triethylamine, tripropylamine, N,N,N',N'-tetramethylethylenediamine, sodium mentholate, and 2-ethyl tetrahydrofurfuryl ether, and may be preferably 2,2-di(2-tetrahydrofuryl)propane, triethylamine, tetramethylethylenediamine, sodium mentholate, or 2-ethyl tetrahydrofurfuryl ether.

[0159] Meanwhile, the polymerization conversion rate may be determined, for example, by measuring the solid concentration in the polymer solution containing the polymer during polymerization. As a specific example, in order to secure the polymer solution, a cylindrical container is attached to the outlet of each polymerization reactor, a certain amount of polymer solution is filled in the cylindrical container, the cylindrical container is separated from the reactor, and the weight (A) of the cylinder filled with the polymer solution is measured. Then, the polymer solution filled in the cylindrical container is transferred to an aluminum container, for example, an aluminum dish, and the weight (B) of the cylindrical container from which the polymer solution has been removed is measured. The aluminum container containing the polymer solution is dried in an oven at 140° C. for 30 minutes, and the weight (C) of the dried polymer is measured, and the polymerization conversion rate may be calculated according to the following mathematical formula 2.

[0160]

number

[0161] In the above Mathematical Formula 2, the total solid content is the total solid content (monomer content) in the polymer solution separated from each reactor, and is the weight percentage of the solid content relative to 100% of the polymer solution. For example, if the total solid content is 20% by weight, it may be calculated by substituting 20 / 100, i.e., 0.2, when applying it to the above Mathematical Formula 2.

[0162] Meanwhile, the polymerized product polymerized in the second reactor may be transferred to the final polymerization reactor and polymerization may be continued until the final polymerization conversion rate reaches 95% or more, and after polymerization in the second reactor, the polymerization conversion rate of each reactor may be appropriately adjusted for each reactor from the third reactor to the final polymerization reactor to adjust the molecular weight distribution. Then, a reaction terminator may be added to deactivate the active sites, and when a modified conjugated diene-based polymer is to be produced, the active polymer may be transferred to a modification reaction process, and the reaction terminator may be applied without limitation as long as it is a substance that can be generally used in the art. In addition, the activated polymer prepared in step (S1) may refer to a polymer in which a polymer anion and an organometallic cation of a polymerization initiator are bonded.

[0163] S2 Step The (S2) step is a modification step in which the activated polymer produced in the (S1) step is reacted with a modifier, and the anionic active site of the activated polymer can react with an alkoxy group bonded to the silane of the modifier. The modifier may be used in an amount of 0.01 mmol to 10 mmol based on a total of 100 g of monomers. In another example, the modifier may be used in a molar ratio of 1:0.1 to 10, 1:0.1 to 5, or 1:0.1 to 1:3 based on 1 mole of the polymerization initiator in the (S1) step.

[0164] According to an embodiment of the present invention, the modifying agent may be added to a modification reactor, and the step (S2) may be carried out in the modification reactor. As another example, the modifying agent may be added to a transfer section for transferring the activated polymer produced in the step (S1) to a modification reactor for carrying out the step (S2), and a reaction may be carried out in the transfer section by mixing the activated polymer and the modifying agent. In this case, the reaction may be a modification reaction in which the modifying agent is simply bonded to the activated polymer, or a coupling reaction in which the activated polymer is linked with the modifying agent as a base.

[0165] Meanwhile, in the method for producing the modified conjugated diene polymer, a step of adding a conjugated diene monomer to the activated polymer produced in the step (S1) and reacting the monomer before the modification reaction in the step (S2) may be further carried out, which is more advantageous for the subsequent modification reaction. In this case, the conjugated diene monomer may be added in an amount of 1 to 100 moles per mole of the activated polymer.

[0166] The method for producing the modified conjugated diene polymer according to one embodiment of the present invention is a method that can satisfy the above-mentioned characteristics of the modified conjugated diene polymer, and the effects that the present invention aims to achieve as described above can be achieved when the above-mentioned characteristics are satisfied. However, in the case of other polymerization conditions, the physical properties of the modified conjugated diene polymer according to the present invention can be realized by controlling them in various ways.

[0167] Rubber composition According to the present invention, there is provided a rubber composition comprising the above-mentioned modified conjugated diene-based polymer and a filler.

[0168] 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. 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.

[0169] 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.

[0170] 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 obtained by modifying or refining the general natural rubber, such as epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber; styrene-butadiene copolymers (SBR), polybutadiene (BR), polyisoprene (IR), butyl rubber (IIR), ethylene-propylene copolymers, polyisobutylene-co-isoprene, neoprene, and the like. The rubber may be a synthetic rubber such as olefin, 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 a mixture of two or more of these.

[0171] 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 is most excellent in improving fracture properties and providing good wet grip properties. The rubber composition may further contain a carbon-based filler as necessary.

[0172] As another example, when silica is used as the filler, a silane coupling agent may be used together to improve reinforcing properties and low heat generation properties.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, or any one or a mixture of two or more of these may be used. Preferably, in consideration of the effect of improving reinforcing properties, bis(3-triethoxysilylpropyl) polysulfide or 3-trimethoxysilylpropyl benzothiazyl tetrasulfide may be used.

[0173] In addition, since 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 an active site as a rubber component, the amount of the silane coupling agent may be reduced from that in the normal case, and 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. Within this range, the effect of the coupling agent is sufficiently exhibited, while the effect of preventing the gelation of the rubber component is also achieved.

[0174] The rubber composition according to one embodiment of the present invention may be sulfur crosslinkable and may further contain a vulcanizing agent. Specifically, the vulcanizing agent may be sulfur powder, and may be contained in an amount of 0.1 to 10 parts by weight per 100 parts by weight of the rubber component. Within this range, the necessary elastic modulus and strength of the vulcanized rubber composition are ensured, and the effect of excellent fuel economy is obtained.

[0175] 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.

[0176] As the vulcanization accelerator, for example, a thiazole-based compound such as M (2-mercaptobenzothiazole), DM (dibenzothiazyl disulfide), or CZ (N-cyclohexyl-2-benzothiazylsulfenamide), or a guanidine-based compound such as DPG (diphenylguanidine) may 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.

[0177] The process oil acts as a softener in the rubber composition and may be, for example, a paraffinic, naphthenic, or aromatic compound. In consideration of tensile strength and abrasion resistance, aromatic process oils may be used, and in consideration of hysteresis loss and low temperature properties, naphthenic or paraffinic process oils may be used. 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. Within this range, there is an effect of preventing a decrease in the tensile strength and low heat generation property (fuel economy) of the vulcanized rubber.

[0178] The anti-aging agent 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.

[0179] The rubber composition according to one embodiment of the present invention can be 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 can be carried out to obtain a rubber composition that has low heat generation and excellent abrasion resistance.

[0180] 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.

[0181] The present invention further provides a tire manufactured using the rubber composition. The tire may include a tire or a tire tread.

[0182] Working Example Hereinafter, the present invention will be described in detail with reference to examples in order to specifically explain the present invention. However, the examples according to the present invention can be modified in various ways, and the scope of the present invention should not be construed as being limited to the examples described below. The examples of the present invention are provided to more completely explain the present invention to those having average knowledge in the art.

[0183] Example 1 Of the three continuous stirred tank reactors (CSTR), n-hexane 5kg / hr, a monomer solution in which 1,3-butadiene was dissolved at 60 wt% in n-hexane 1.16 kg / hr, a monomer solution in which styrene was dissolved at 60 wt% in n-hexane 0.31 kg / hr, an initiator solution in which n-butyllithium was dissolved at 6.6 wt% in n-hexane 8.33 g / hr, and a polar additive solution in which ditetrahydrofurylpropane was dissolved at 2 wt% in n-hexane as a polar additive were continuously fed into the first reactor at a flow rate of 2.25 g / hr. At this time, the internal temperature of the reactor was maintained at 60°C, and when the polymerization conversion rate reached 70%, the polymer was transferred from the first reactor to the second reactor through the transfer pipe.

[0184] Then, the temperature of the second reactor was maintained at 60°C, and 0.2 kg / hr of a solution in which 1,3-butadiene was dissolved at 60 wt% in n-hexane and 6 g / hr of a polar additive solution in which ditetrahydrofurylpropane was dissolved at 10 wt% in n-hexane were continuously added to the second reactor to participate in the reaction, and when the polymerization conversion rate reached 95% or more, the polymer was transferred from the second reactor to the third reactor through the transfer pipe, and 11.6 g / hr of a solution in which N,N-dimethyl-3-(trimethoxysilyl)propan-1-amine was dissolved at 5 wt% in n-hexane as a modifier was added, and the reaction was carried out for 30 minutes.

[0185] Then, a 30 wt% solution of IR1520 (BASF) as an antioxidant was added at a rate of 100 g / h and stirred. The resulting polymer was placed in hot water heated with steam and stirred to remove the solvent, and then roll-dried to remove the remaining solvent and water, producing a modified conjugated diene copolymer.

[0186] Example 2 In Example 1, a monomer solution in which 1,3-butadiene was dissolved in n-hexane at 60 wt%, a monomer solution in which styrene was dissolved in n-hexane at 60 wt%, and a polar additive solution in which ditetrahydrofurylpropane was dissolved in n-hexane at 2 wt% were continuously fed into the first reactor at 1.13 kg / hr, 0.28 kg / hr, and 4.0 g / hr of a polar additive solution in which ditetrahydrofurylpropane was dissolved in n-hexane at 2 wt% as a polar additive, were continuously fed into the first reactor. A modified conjugated diene-based polymer was produced in the same manner as in Example 1, except that the polymerization conversion rate in the first reactor was 72%, and the polymer was transferred from the first reactor to the second reactor.

[0187] Example 3 A modified conjugated diene-based polymer was produced in the same manner as in Example 1, except that the temperature of the first reactor was maintained at 70°C, the temperature of the second reactor was maintained at 65°C, and the polymerization conversion rate of the first reactor was 80% when the polymerization was transferred to the second reactor.

[0188] Example 4 A modified conjugated diene-based polymer was produced in the same manner as in Example 1, except that when the polymerization conversion rate in the first reactor was 77%, the polymer was transferred from the first reactor to the second reactor, and the 1,3-butadiene solution additionally charged to the second reactor was not charged to the second reactor.

[0189] Example 5 The same procedure as in Example 1 was carried out to produce a modified conjugated diene polymer, except that a solution of 5 wt% bis(3-(diethoxymethylsilylpropyl)-N-methylamine) dissolved in n-hexane was added at 23.0 g / hr instead of N,N-dimethyl-3-(trimethoxysilyl)propan-1-amine as a modifying agent.

[0190] Example 6 In Example 1, a monomer solution in which 1,3-butadiene was dissolved in n-hexane at 60 wt%, a monomer solution in which styrene was dissolved in n-hexane at 60 wt%, and a polar additive solution in which ditetrahydrofurylpropane was dissolved in n-hexane at 2 wt% were continuously fed into the first reactor at 1.08 kg / hr, 0.35 kg / hr, and 3.0 g / hr of a polar additive solution in which ditetrahydrofurylpropane was dissolved in n-hexane at 2 wt% as a polar additive. When the polymerization conversion rate in the first reactor was 75%, the polymer was transferred from the first reactor to the second reactor, and the 1,3-butadiene was additionally fed into the second reactor. The same procedure as in Example 1 was carried out, except that the 3-butadiene solution was continuously fed at 0.24 kg / hr, and a solution of 5 wt% bis(3-(diethoxymethylsilylpropyl)-N-methylamine) dissolved in n-hexane was fed at 23.0 g / hr instead of N,N-dimethyl-3-(trimethoxysilyl)propan-1-amine as the modifier, to produce a modified conjugated diene polymer.

[0191] Example 7 A modified conjugated diene-based polymer was produced in the same manner as in Example 1, except that when the polymerization conversion rate in the first reactor was 73%, the polymer was transferred from the first reactor to the second reactor, and a polar additive solution in which ditetrahydrofurylpropane was dissolved at 10 wt% in n-hexane was continuously added to the second reactor at a rate of 15.0 g / hr.

[0192] Example 8 A modified conjugated diene-based polymer was produced in the same manner as in Example 2, except that when the polymerization conversion rate in the first reactor was 73%, the polymer was transferred from the first reactor to the second reactor, and a solution of 5 wt% bis(3-(diethoxymethylsilylpropyl)-N-methylamine) dissolved in n-hexane was added at 23.0 g / hr as a modifying agent instead of N,N-dimethyl-3-(trimethoxysilyl)propan-1-amine.

[0193] Comparative Example 1 In Example 1, a polar additive solution in which ditetrahydrofurylpropane was dissolved in n-hexane at 2 wt% was introduced into the first reactor at a rate of 17.5 g / hr, and when the polymerization conversion rate of the first reactor was 78%, the polymer was transferred to the second reactor. The same procedure as in Example 1 was carried out except that 1,3-butadiene and polar additive were not introduced into the second reactor, to produce a modified conjugated diene-based polymer.

[0194] Comparative Example 2 In Example 6, a polar additive solution in which ditetrahydrofurylpropane was dissolved in n-hexane at 2 wt% was fed to the first reactor at a rate of 6.0 g / hr, and when the polymerization conversion rate of the first reactor was 73%, the polymer was transferred to the second reactor. The same procedure as in Example 6 was carried out except that 1,3-butadiene and polar additive were not fed to the second reactor, to produce a modified conjugated diene-based polymer.

[0195] Comparative Example 3 A modified conjugated diene-based polymer was produced in the same manner as in Comparative Example 1, except that when the polymerization conversion rate of the first reactor was 72%, the polymer was transferred to the second reactor, and a solution of 60 wt% of 1,3-butadiene dissolved in n-hexane was introduced into the second reactor at a rate of 0.2 kg / hr to carry out a polymerization reaction.

[0196] Comparative Example 4 In Comparative Example 1, a monomer solution of 60 wt% 1,3-butadiene dissolved in n-hexane was introduced into the first reactor at 1.08 kg / hr, a monomer solution of 60 wt% styrene dissolved in n-hexane was introduced at 0.35 kg / hr, and a polar additive solution was introduced at 12.0 g / hr. When the polymerization conversion rate of the first reactor was 76%, the polymer was transferred to the second reactor. A solution of 60 wt% 1,3-butadiene dissolved in n-hexane was introduced into the second reactor at 0.2 kg / hr to perform a polymerization reaction. The same procedure as in Comparative Example 1 was carried out to produce a modified conjugated diene-based polymer.

[0197] Comparative Example 5 A modified conjugated diene-based polymer was produced in the same manner as in Example 1, except that the polymer was transferred to the second reactor when the polymerization conversion rate in the first reactor was 65%.

[0198] Comparative Example 6 A modified conjugated diene-based polymer was produced in the same manner as in Example 1, except that the polymer was transferred to the second reactor when the polymerization conversion rate in the first reactor was 87%.

[0199] Comparative Example 7 In Comparative Example 1, a monomer solution of 60 wt% 1,3-butadiene dissolved in n-hexane was introduced into the first reactor at 1.16 kg / hr, a monomer solution of 60 wt% styrene dissolved in n-hexane was introduced at 0.31 kg / hr, and a polar additive solution was introduced at 5.0 g / hr. When the polymerization conversion rate of the first reactor was 75%, the polymer was transferred to the second reactor. Instead of a modifying agent, a solution of 4.5 wt% silicon tetrachloride dissolved in n-hexane was continuously introduced at 3.7 g / hr to carry out a coupling reaction. An unmodified conjugated diene-based polymer was produced in the same manner as in Comparative Example 1.

[0200] Experimental Example 1. Evaluation of polymer properties For each modified or unmodified conjugated diene polymer prepared in the above examples and comparative examples, the styrene unit content and vinyl content in the polymer, weight average molecular weight (Mw, ×10 3 g / mol), number average molecular weight (Mn, ×10 3 The molecular weight distribution (PDI, MWD), glass transition temperature, glass transition onset temperature, glass transition end temperature, and full width at half maximum of the tan δ peak were measured. The results are shown in Table 1 below.

[0201] 1) Styrene unit and vinyl content (wt%) The styrene unit (SM) and vinyl content in each of the polymers were measured and analyzed using a Varian VNMRS 500 MHz NMR.

[0202] In the 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 and vinyl contents were calculated by assuming that 7.2 to 6.9 ppm was the peak for random styrene, 6.9 to 6.2 ppm was the peak for block styrene, 5.8 to 5.1 ppm was the peak for 1,4-vinyl and 1,2-vinyl, and 5.1 to 4.5 ppm was the peak for 1,2-vinyl.

[0203] 2) Weight average molecular weight (Mw, ×10 3 g / mol), number average molecular weight (Mn, ×10 3 g / mol), and molecular weight distribution (PDI, MWD) The number average molecular weight (Mn) and weight average molecular weight (Mw) were measured by gel permeation chromatography (GPC) (PL GPC220, Agilent Technologies) under the following conditions, and the molecular weight distribution was calculated by dividing the weight average molecular weight by the number average molecular weight.

[0204] -Column: Two PLgel Olexis (Polymer Laboratories) columns and one PLgel mixed-C (Polymer Laboratories) column were used in combination. -Solvent: 2% by weight of amine compound mixed in tetrahydrofuran -Flow rate: 1mL / min -Sample concentration: 1-2mg / mL (diluted in THF) -Injection volume: 100uL -Column temperature: 40℃ -Detector: Refractive index -Standard: Polystyrene (corrected by a cubic function)

[0205] 3) Glass transition temperature (Tg, °C), glass transition onset temperature (T g-on , °C), and glass transition end temperature (T g-off 、℃) In accordance with ISO 22768:2006, a differential scanning calorimetry curve (DSC curve) was recorded using a differential scanning calorimetry (DSCQ100, TA Corporation) while heating from -100°C at 10°C / min under a nitrogen flow of 50 ml / min. In this curve, the temperature at which the glass transition begins was defined as the glass transition onset temperature, the temperature at which the glass transition ends was defined as the glass transition end temperature, and the peak top (inflection point) of the DSC differential curve was defined as the glass transition temperature.

[0206] 4) Full Width Half Maximum (FWHM) of tan δ peak For the polymers prepared in the examples and comparative examples, dynamic viscoelasticity analysis by ARES (Advanced Rheometric Expansion System) was performed using a dynamic mechanical analyzer (TA, ARES-G2) in a torsional mode at a frequency of 10 Hz, a strain of 0.5%, and a heating rate of 5°C / min in the temperature range of -100°C to 100°C, to obtain a tan δ graph as shown in FIG. 1, from which the full width at half maximum of the peak was calculated.

[0207] [Table 1]

[0208] Referring to Table 1, in the case of the modified conjugated diene-based polymer produced by the production method according to the present invention, the glass transition onset temperature (T g-on ) and the glass transition end temperature (offset, T g-off ) is 20° C. or more and 30° C. or less, and the full width at half maximum of the tan δ peak is also 20° C. or more.

[0209] In contrast, in the comparative example not produced by the production method according to the present invention, the difference between the glass transition onset temperature and the glass transition end temperature was less than 10°C, and the full width at half maximum of the tan δ peak was also less than 20°C.

[0210] From the above results, it can be seen that the manufacturing method of the present invention enables precise control of the polymer microstructure, adjustment of the difference between the glass transition onset temperature and the glass transition end temperature, and further increases the full width at half maximum of the tan δ peak.

[0211] Experimental example 2. Evaluation of properties of rubber molded products 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, viscoelastic properties, and abrasion resistance were measured, and the results are shown in Table 3 below.

[0212] 1) Preparation of rubber test specimens The modified or unmodified conjugated diene polymers of the Examples and Comparative Examples were used as raw rubber and were compounded under the compounding conditions shown in Table 2. The raw material contents in Table 2 are each in parts by weight based on 100 parts by weight of the raw rubber.

[0213] [Table 2]

[0214] Specifically, the rubber test piece is 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 kneader. At this time, the initial temperature of the kneader was controlled at 70°C, and after the completion of the mixing, the primary compound was obtained at a discharge temperature of 145°C. In the second mixing stage, the primary compound was cooled to room temperature, and then the primary compound, sulfur, rubber accelerator (DPD (diphenyl guanidine)), and vulcanization accelerator (CZ (N-cyclohexyl-2-benzothiazylsulfenamide)) were added to the kneader and mixed at a temperature of 100°C or less to obtain a secondary compound. Then, a curing process was performed at 160°C for 20 minutes to produce a rubber test piece.

[0215] 2) Viscoelastic properties For rubber test pieces prepared containing the polymers produced in the above Examples and Comparative Examples, a dynamic mechanical analyzer (TA, ARES-G2) was used to measure tan δ according to temperature in the temperature range of -100°C to 100°C in a torsional mode at a frequency of 10Hz, a deformation rate (Strain) of 0.5%, and a heating rate of 5°C / min, and a tan δ graph was obtained. From the obtained tan δ graph, the tan δ value at 0°C and the tan δ value at 60°C were confirmed. In this case, the higher the tan δ value at the low temperature of 0°C, the better the wet skid resistance, and the lower the tan δ value at the high temperature of 60°C, the lower the hysteresis loss and the better the running resistance (fuel economy). The results in the following Table 3 are indexed based on the measurement results of Comparative Example 7, so the higher the value, the better the performance.

[0216] 3) Abrasion resistance (DIN abrasion test) A DIN abrasion test was performed on each rubber test piece in accordance with ASTM D5963, and the results were expressed as DIN loss index (loss volume index: ARIA (Abration resistance index, Method A)). The results in Table 3 below are indexed based on the measurement results of Comparative Example 7, so the higher the value, the better.

[0217] [Table 3]

[0218] Referring to Table 3, it can be seen that the rubber test pieces containing the modified conjugated diene polymers according to the present invention, in which the difference between the glass transition onset temperature and the glass transition finish temperature is 10° C. or more and 30° C. or less, exhibit well-balanced improved wet skid resistance and running resistance, and also exhibit significantly improved abrasion resistance. In contrast, the rubber test pieces containing the modified conjugated diene polymers of Comparative Examples 1 to 6, in which the difference between the glass transition onset temperature and the glass transition finish temperature is less than 10° C., exhibit significantly lower running resistance and significantly poorer abrasion resistance than the examples.

[0219] From the above results, it was confirmed that the modified conjugated diene-based polymer of the present invention has an excellent balance of wet skid resistance and running resistance and improved abrasion resistance by controlling the microstructure so that the difference between the glass transition onset temperature and the glass transition end temperature is 10°C or more and 30°C or less.

Claims

1. The copolymer comprises a repeating unit derived from a conjugated diene monomer, a repeating unit derived from an aromatic vinyl monomer, and a functional group derived from a modifier, When measured by differential scanning calorimetry (DSC), the glass transition onset temperature (onset, T ｇ－ｏｎ ) and glass transition end temperature (offset, T ｇ－ｏｆｆ ) is 10°C or more and 30°C or less, In a tan δ graph according to temperature derived from dynamic viscoelastic analysis by ARES (Advanced Rheometric Expansion System), the full width at half maximum (FWHM) value of a tan δ peak appearing in the temperature range of −100° C. to 100° C. is 20° C. or more; The ARES is measured using a dynamic mechanical analyzer in a torsion mode under the conditions of a frequency of 10 Hz, a deformation rate (Strain) of 0.5%, and a heating rate of 5° C. / min. for the modified conjugated diene polymer.

2. The glass transition onset temperature (T ｇ－ｏｎ ) and glass transition end temperature (T ｇ－ｏｆｆ 2. The modified conjugated diene polymer according to claim 1, wherein the difference between the temperature of the modified conjugated diene polymer and the temperature of the polymer is 15° C. or more and 30° C. or less.

3. The modified conjugated diene polymer according to claim 1 or 2, which has a glass transition temperature (Tg) of -100°C or higher and 20°C or lower.

4. The modified conjugated diene-based polymer according to claim 1 , wherein the full width at half maximum of the tan δ peak is 30° C. or more and 80° C. or less.

5. The conjugated diene-based polymer according to any one of claims 1 to 4, wherein the tan δ peak appears in a temperature range of -80°C to 20°C.

6. The modified conjugated diene polymer according to any one of claims 1 to 5, wherein a molecular weight distribution curve determined by gel permeation chromatography is unimodal and the molecular weight distribution is 1.0 to 3.

0.

7. The modified conjugated diene polymer according to any one of claims 1 to 6, wherein the modifying agent is an alkoxysilane compound containing an N-containing functional group.

8. A rubber composition comprising the modified conjugated diene-based polymer according to claim 1 and a filler.

9. The rubber composition according to claim 8, comprising 0.1 to 200 parts by weight of a filler based on 100 parts by weight of the modified conjugated diene polymer.

10. The rubber composition according to claim 8 or 9, wherein the filler is a silica-based filler or a carbon black-based filler.

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