KR102776321B1 - Modified conjugated diene polymer and rubber composition comprising the same - Google Patents

Abstract

The present invention relates to a modified conjugated diene polymer and a rubber composition comprising the same, and provides a modified conjugated diene polymer that satisfies the following conditions: i) repeating unit derived from aromatic vinyl monomer: 0 wt%, ii) Mooney viscosity measured under ASTM D1646 conditions: 40 to 100, iii) phase difference index at 0.1 Hz measured at 160°C: 0.65 or more, iv) content of Si atoms and N atoms: 50 ppm or more with respect to the total weight of the polymer, and v) Mooney relaxation rate measured at 100°C: 0.5 or more.

Description

Modified conjugated diene polymer and rubber composition comprising the same {MODIFIED CONJUGATED DIENE POLYMER AND RUBBER COMPOSITION COMPRISING THE SAME}

The present invention relates to a modified conjugated diene polymer and a rubber composition comprising the same.

Recently, as interest in energy conservation and environmental issues has increased, there has been a demand for fuel efficiency in automobiles. Accordingly, materials that have low driving resistance, excellent wear resistance and tensile properties, and also have steering stability represented by wet skid resistance are required as rubber materials for tires.

In order to reduce the running resistance of tires, there is a method to reduce the hysteresis loss of vulcanized rubber, and as evaluation indices of such vulcanized rubber, rebound elasticity, tan δ, and Goodrich heat generation at 50°C to 80°C are used. In other words, a rubber material having a large rebound elasticity or a small tan δ and Goodrich heat generation at the above temperature is desirable.

As one of the methods for realizing this, a method of lowering the heat generation of a tire by using an inorganic filler such as silica or carbon black in a rubber composition for forming a tire has been proposed. However, this has a problem in that the inorganic filler is not easily dispersed in the rubber composition, and thus the overall physical properties of the rubber composition, including wear resistance, crack resistance, and processability, are deteriorated.

In order to solve such a problem, a method of modifying the polymerization-active portion of a conjugated diene polymer obtained by anionic polymerization using organolithium to increase the dispersibility of inorganic fillers such as silica or carbon black in a rubber composition with a modifying agent containing a functional group capable of interacting with the inorganic filler has been proposed. However, although the low heat generation is improved, there is still a problem that the tensile properties, wear resistance, and processability are reduced.

Therefore, with the recent increase in the demand for low fuel efficiency, there is a need to develop a rubber composition that has improved fuel efficiency characteristics and wet road braking performance in tires along with well-balanced tensile characteristics.

JP WO2013-077018 A1

The present invention has been made to solve the problems of the above-mentioned prior art, and aims to provide a modified conjugated diene polymer which does not contain a repeating unit derived from an aromatic vinyl monomer, thereby controlling the Mooney viscosity, Mooney relaxation rate, and phase difference index thereof, thereby improving the rolling resistance characteristics and wear resistance of a rubber composition when applied to the rubber composition.

In addition, the present invention aims to provide a rubber composition having improved cloud resistance and wear resistance, which comprises the modified conjugated diene polymer and a filler.

According to one embodiment of the present invention for solving the above problems, the present invention provides a modified conjugated diene polymer satisfying the following conditions i) to v):

i) Repeating unit derived from aromatic vinyl monomer: 0 wt%, ii) Mooney viscosity measured under ASTM D1646 conditions: 40 to 100, iii) Retardation index at 0.1 Hz measured at 160°C: 0.65 or more, iv) Si atom and N atom content: 50 ppm or more with respect to the total weight of the polymer, and v) Mooney relaxation rate measured at 100°C: 0.5 or more.

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

The modified conjugated diene polymer according to the present invention is a polymer composed of a conjugated diene monomer-derived repeating unit that does not include an aromatic vinyl monomer-derived repeating unit, and has Mooney viscosity, Mooney relaxation rate and phase difference index that are comprehensively controlled within a specific range, so that when applied to a rubber composition, the rolling resistance characteristics and wear resistance of the rubber composition can be improved.

In addition, the rubber composition according to the present invention can have excellent cloud resistance characteristics and wear resistance by including the above-described modified conjugated diene polymer and a filler.

Hereinafter, the present invention will be described in more detail to help understand the present invention.

The terms or words used in the description and claims of the present invention should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical idea of the present invention, based on the principle that the inventor can appropriately define the concept of the term in order to explain his or her own invention in the best manner.

definition

The term 'polymer' as used herein refers to a polymer compound prepared by polymerizing monomers, whether of the same or different types. Thus, the general term polymer encompasses the terms homopolymer and copolymer, which are usually used to refer to polymers prepared from only one type of monomer.

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

In the present invention, the term 'divalent hydrocarbon group' may mean a divalent atomic group in which carbon and hydrogen are bonded, such as a divalent alkylene group, an alkenylene group, an alkynylene group, a cycloalkylene group, a cycloalkylene group including one or more unsaturated bonds, and an arylene group, and the minimum number of carbon atoms of a substituent represented by a divalent hydrocarbon group may be determined according to the type of each substituent.

In the present invention, the term 'alkyl group' may mean a monovalent aliphatic saturated hydrocarbon, and may include both linear alkyl groups such as methyl, ethyl, propyl, and butyl, and branched alkyl groups such as isopropyl, sec-butyl, tert-butyl, and neo-pentyl.

In the present invention, the term 'alkenyl group' may mean a monovalent aliphatic unsaturated hydrocarbon containing one or more double bonds.

In the present invention, the term 'alkynyl group' may mean a monovalent aliphatic unsaturated hydrocarbon containing one or more triple bonds.

In the present invention, the term 'alkylene group' may mean a divalent aliphatic saturated hydrocarbon such as methylene, ethylene, propylene, and butylene.

In the present invention, the term 'aryl group' may mean a cyclic aromatic hydrocarbon, and may also mean a monocyclic aromatic hydrocarbon in which one ring is formed, or a polycyclic aromatic hydrocarbon in which two or more rings are combined.

In the present invention, the term 'heterocyclic group' means a group in which one or more carbon atoms in a cycloalkyl group or an aryl group are substituted with a heteroatom, and may include, for example, both a heterocycloalkyl group and a heteroaryl group.

As used herein, the terms "comprising," "having," and their derivatives are not intended to exclude the presence of any additional component, step, or procedure, whether or not specifically disclosed. In order to avoid any doubt, all compositions claimed through use of the term "comprising" may include any additional additive, adjuvant, or compound, whether polymeric or otherwise, unless stated to the contrary. In contrast, the term "consisting essentially of" excludes from the scope of any subsequent description any other component, step, or procedure, excepting those that are not essential to operability. The term "consisting of" excludes any component, step, or procedure not specifically described or enumerated.

Measurement method and conditions

In this specification, 'weight average molecular weight (Mw)', 'number average molecular weight (Mn)', and 'molecular weight distribution (MWD)' are measured through GPC (gel permeation chromatography) analysis, and are measured by checking the molecular weight distribution curve. The molecular weight distribution (PDI, MWD, Mw/Mn) is calculated from each measured molecular weight. Specifically, the GPC is used by combining two PLgel Olexis (Polymer Laboratories) columns and one PLgel mixed-C (Polymer Laboratories) column, and when calculating molecular weight, the GPC standard material is PS (polystyrene), and the GPC measurement solvent is prepared by mixing 2 wt% of an amine compound into tetrahydrofuran.

In this specification, 'Mooney viscosity (MV)' and 'Mooney relaxation rate (-S/R)' are measured using MV-2000 (ALPHA Technologies) at 100℃, Rotor Speed 2±0.02 rpm, Large Rotor. The sample used at this time is left at room temperature (23±3℃) for more than 30 minutes, then 27±3 g is collected, filled into the die cavity, and the Platen is operated to measure for 4 minutes. After measuring Mooney viscosity, the slope value of the Mooney viscosity change that appears when the torque is released is measured, and its absolute value is taken as the Mooney relaxation rate.

In this specification, the 'phase difference index' refers to the Tan δ value at 0.1 Hz in a Tan δ graph against frequency (Hz) obtained by measuring under the conditions of 160℃ and 7% strain (0.5 degree) using a SCARABAEUS INSTRUMENTS SYSTEMS (SIS) V-50 Rubber Process Analyzer of SCARABAEUS Co., Ltd. Specifically, about 6 g of a polymer is prepared, placed on a disk, and measured using the analyzer under the above conditions to obtain a Tan δ graph against frequency (Hz), and the Tan δ value at 0.1 Hz is read here and expressed as the phase difference index.

In this specification, the 'Si content' is measured using an inductively coupled plasma optical emission spectrometer (ICP-OES; Optima 7300DV) as an ICP analysis method. When using the inductively coupled plasma optical emission spectrometer, about 0.7 g of a sample is placed in a platinum crucible, about 1 mL of concentrated sulfuric acid (98 wt%, Electronic grade) is added, and the sample is heated at 300°C for 3 hours, and the sample is annealed in an electric furnace (Thermo Scientific, Lindberg Blue M) using the following program of steps 1 to 3,

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)

Add 1 mL of concentrated nitric acid (48 wt%) and 20 ㎕ of concentrated hydrofluoric acid (50 wt%) to the residue, seal the platinum crucible, and shake for more than 30 minutes. Add 1 mL of boric acid to the sample, store at 0°C for more than 2 hours, dilute in 30 mL of ultrapure water, and perform incineration for measurement.

In the present invention, the ‘N content’ may be measured through the NSX analysis method, and the NSX analysis method may be measured using a trace nitrogen quantitative analyzer (NSX-2100H).

For example, in case of using the above trace nitrogen quantitative analyzer, the trace nitrogen quantitative analyzer (Auto sampler, Horizontal furnace, PMT & Nitrogen detector) was turned on and the carrier gas flow rates were set to 250 ml/min for Ar, 350 ml/min for _O2 , and 300 ml/min for ozonizer, and the heater was set to 800℃, and then the analyzer was stabilized for about 3 hours. After the analyzer was stabilized, a calibration curve was created with a Nitrogen standard (AccuStandard S-22750-01-5 ml) for a calibration curve range of 5 ppm, 10 ppm, 50 ppm, 100 ppm, and 500 ppm, and the Area corresponding to each concentration was obtained, and a straight line was created using the ratio of the Area to the concentration. Thereafter, a ceramic boat containing 20 mg of the sample was placed on the Auto sampler of the analyzer and measured to obtain the area. The N content was calculated using the area of the obtained sample and the above calibration curve.

At this time, the sample used in the above NSX analysis method may be a modified conjugated diene polymer sample that has been stirred in hot water heated with steam to remove the solvent, and may be a sample from which residual monomer and residual denaturant have been removed. In addition, if oil is added to the above sample, it may be a sample after the oil has been extracted (removed).

The present invention provides a modified conjugated diene polymer that does not contain a repeating unit derived from an aromatic vinyl monomer, which can be applied to a rubber composition to improve the cloud resistance characteristics and wear resistance of the rubber composition by having various properties comprehensively controlled within specific ranges.

The modified conjugated diene polymer according to one embodiment of the present invention is characterized by simultaneously satisfying all of the following conditions i) to v).

i) Aromatic vinyl monomer-derived repeating unit content: 0 wt%,

ⅱ) Mooney viscosity measured under ASTM D1646 conditions: 40 to 100,

ⅲ) Phase difference index at 0.1 Hz measured at 160℃: 0.65 or more,

ⅳ) Si atom and N atom content: 50 ppm or more based on the total weight of the polymer, and

ⅴ) Mooney relaxation rate measured at 100℃: 0.5 or more.

According to one embodiment of the present invention, the modified conjugated diene polymer may include a repeating unit derived from a conjugated diene monomer and a functional group derived from a modifier, wherein the repeating unit derived from the conjugated diene monomer may refer to a repeating unit formed when the conjugated diene monomer is polymerized, and the functional group derived from the modifier may refer to a functional group derived from a modifier present at one end of the active polymer through a reaction or coupling between the active polymer prepared by polymerizing the conjugated diene monomer and the modifier.

According to one embodiment of the present invention, the conjugated diene monomer may be 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).

As another example, the modified conjugated diene polymer may include a repeating unit derived from a conjugated diene monomer, a functional group derived from a modification initiator, and a functional group derived from a modification agent, in which case the modified conjugated diene polymer may be a double-ended modified conjugated diene polymer including a functional group derived from a modification initiator on one side and a functional group derived from a modification agent on the other side.

As another example, the modified conjugated diene polymer may be a copolymer further including a repeating unit derived from a diene monomer having 1 to 10 carbon atoms together with 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 modified conjugated diene polymer is a copolymer further including a diene monomer, the modified conjugated diene polymer may include a repeating unit derived from the diene monomer in an amount of from more than 0 wt% to 1 wt%, from more than 0 wt% to 0.1 wt%, from more than 0 wt% to 0.01 wt%, or from more than 0 wt% to 0.001 wt%, and has an effect of preventing gel formation within this range.

According to one embodiment of the present invention, the modified conjugated diene polymer must have a Mooney viscosity of 40 to 100 as measured under ASTM D1646 conditions, and specifically, may be 40 to 90, and preferably may be 50 to 90. There may be various measures for evaluating processability, but when the Mooney viscosity satisfies the above range, the processability may be considerably excellent.

According to one embodiment of the present invention, the modified conjugated diene polymer may have a number average molecular weight (Mn) of 1,000 g/mol to 2,000,000 g/mol, 10,000 g/mol to 1,000,000 g/mol, or 100,000 g/mol to 800,000 g/mol as measured by gel permeation chromatography (GPC), and a weight average molecular weight (Mw) of 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 1,500,000 g/mol, and within this range, has excellent cloud resistance characteristics and wet road resistance.

As another example, the modified conjugated diene polymer has a molecular weight distribution (PDI; MWD; Mw/Mn) of 1.5 to 3.5, preferably 1.5 to 3.0, or 1.5 to 2.5, or 1.5 to 2.0, and within this range, the polymer has excellent tensile properties and viscoelastic properties, and has an excellent balance between each property.

In addition, the modified conjugated diene polymer may have a unimodal shape in the molecular weight distribution curve by gel permeation chromatography (GPC), and the unimodal shape may be determined by the methodological aspect of continuous polymerization and the aspect of the modification reaction performed by the modification agent or coupling agent.

The Mooney relaxation rate measured at 100°C of the above-described modified conjugated diene polymer can be an indicator of the degree of branching of the modified conjugated diene polymer. The Mooney relaxation rate of the modified conjugated diene polymer at 100°C is 0.5 or more, and may be 0.5 to 1.2 or 0.6 to 1.0. In addition, a higher Mooney relaxation rate can mean a lower degree of branching (higher linearity).

The Mooney relaxation rate measured at 100°C of the above-described modified conjugated diene polymer can be an indicator of the degree of branching of the modified conjugated diene polymer as described above, and as the Mooney relaxation rate increases, the degree of branching of the modified conjugated diene polymer tends to decrease. For example, in the case of modified conjugated diene polymers having the same level of Mooney viscosity, the Mooney relaxation rate increases as the number of branches decreases, and therefore, the Mooney viscosity can also be used as an indicator of linearity.

In order to make the Mooney relaxation rate 0.5 or higher, for example, this can be achieved by controlling the weight average molecular weight and the degree of branching of the polymer to be produced within a range where the Mooney viscosity of the modified conjugated diene polymer is 40 to 100. When the weight average molecular weight decreases, the degree of branching can be increased, and when the weight average molecular weight increases, the degree of branching can be decreased. This can be controlled by the number of functional groups of the modifier, the amount of the modifier added, or the progress of metallation. In particular, when the number of functional groups of the modifier is adjusted to 6 or less, or to 2 or more and 6 or less, the Mooney relaxation rate can be more easily adjusted to 0.5 or higher. For example, a modifier can react with an active end of a polymer chain formed by polymerization of monomers to introduce a functional group into the polymer chain, and at the same time act as a coupling agent to couple the polymer chain, thereby inducing branching of the polymer. Accordingly, when the number of functional groups of the modifier exceeds 6, the number of coupled polymer chains increases, resulting in a branched polymer structure, and a Mooney relaxation rate of 0.5 or higher cannot be exhibited.

In addition, the modified conjugated diene polymer according to one embodiment of the present invention should have a retardation index of 0.65 or more at 0.1 Hz measured at 160°C, and may preferably be 0.65 to 5, or 0.7 to 3.5. Within this range, the degree of branching of the polymer may be controlled to exhibit a Mooney relaxation rate of 0.5 or more. Meanwhile, the retardation index may vary depending on the degree of branching of the polymer, but is not determined solely by the degree of branching, and may vary depending on the polymerization method and conditions.

According to one embodiment of the present invention, the modified conjugated diene polymer may have an N and Si content of 50 ppm or more, 70 ppm to 10,000 ppm, or 100 ppm to 5,000 ppm based on weight, respectively, and within this range, the mechanical properties such as tensile properties and viscoelastic properties of a rubber composition including the modified conjugated diene polymer are excellent. The N content and the Si content may each mean the content of Si atoms present in the modified conjugated diene polymer. Meanwhile, the N atoms and the Si atoms may be derived from a modifier, or may be derived from at least one of a modification initiator and a modifier.

Meanwhile, the modified conjugated diene polymer according to one embodiment of the present invention may have a modification rate of 30% or more.

In addition, the modified conjugated diene polymer may have a modification rate of 50% or more, and when the content of N atoms and Si atoms is 50 ppm (by weight) or more, the modification rate may be 30% or more, and this modification rate does not change independently of the content of N atoms and Si atoms, but may change dependently to a certain extent.

However, in the modification reaction, the content of N atoms and Si atoms and the modification rate may exhibit some independence depending on the extent of coupling by the modification agent, and in order to achieve a high modification rate of 50% or more, preferably 55% or more, or 60% or more, and optimally 70% or more, it is necessary to reduce the amount of polymer coupled during the modification reaction, and this can be controlled by the amount of the modification agent added, the amount of the polar additive, the reaction time, the mixing time and the degree of mixing of the modification agent and the active polymer, etc.

As described above, when the modified conjugated diene polymer according to the present invention satisfies the above-described conditions, the rolling resistance characteristics can be significantly improved during mixing due to reasons such as improved affinity with fillers such as silica or carbon black, and at the same time, the wear resistance can be improved. Furthermore, in the case of the modified conjugated diene polymer that additionally satisfies the above-described modification rate conditions, the tensile characteristics can be significantly improved in addition to the rolling resistance characteristics and wear resistance.

Meanwhile, the modified conjugated diene polymer according to one embodiment of the present invention may be manufactured through batch or continuous polymerization, and may be manufactured under conditions in which temperature, amount of reactants, timing of introduction of reactants, polymerization initiator, modifier, and polymerization reaction speed are controlled so as to simultaneously satisfy the above specific conditions, and the manufacturing method can be performed by appropriately controlling the above conditions so that the desired properties are expressed.

For example, the modified conjugated diene polymer may be manufactured by a manufacturing method including a step (S1) of manufacturing an active polymer by polymerizing a conjugated diene monomer in the presence of a polymerization initiator in a hydrocarbon solvent; and a step (S2) of reacting the active polymer manufactured in step (S1) with a modifying agent, wherein the polymerization reaction (S1) and the modification reaction (S2) are performed continuously, the step (S1) is performed in two or more polymerization reactors, and the polymerization conversion rate in the first polymerization reactor among the polymerization reactors is 50% or less.

The above polymerization initiator may be an organometallic compound, or a modified initiator prepared by reacting a compound containing a modified functional group, an organometallic compound, and a conjugated diene monomer. In terms of satisfying all of the above-described properties of the modified conjugated diene polymer, it may be preferable that the polymerization initiator be the above-described modified initiator.

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

According to one embodiment of the present invention, the polymerization initiator can 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 used for polymerization.

When the polymerization initiator is an organometallic compound, the organometallic compound is not particularly limited and may be a common organometallic compound as long as it can easily initiate polymerization and does not affect the polymer properties, and examples thereof include methyllithium, ethyllithium, propyllithium, isopropyllithium, n-butyllithium, s-butyllithium, t-butyllithium, hexyllithium, n-decyllithium, t-octyllithium, phenyllithium, 1-naphthyllithium, n-eicosyllithium, 4-butylphenyllithium, 4-tolyllithium, cyclohexyllithium, 3,5-di-n-heptylcyclohexyllithium, 4-cyclopentyllithium, naphthylsodium, naphthylpotassium, lithium alkoxide, sodium alkoxide, potassium alkoxide, lithium sulfonate, sodium sulfonate, potassium sulfonate, lithium amide, sodium amide, It may be at least one selected from the group consisting of potassium amide and lithium isopropylamide.

In addition, when the polymerization initiator is a modification initiator, the modification initiator may be an oligomer-type material produced by reacting a compound containing a modification functional group, an organometallic compound, and a conjugated diene monomer as described above.

Specifically, the above-described modified initiator is manufactured by reacting a modified functional group-containing compound, an organometallic compound, and a conjugated diene monomer in a batch or continuous manner, wherein the modified functional group-containing compound is reacted in an excess ratio with respect to the organometallic compound, and the conjugated diene monomer may be reacted in a ratio of 0.5 to 5 mol based on 1 mol of the modified functional group-containing compound. In this case, the modified functional group-containing compound can be induced to bind in the form of an oligomer, and by using the conjugated diene monomer, the modified initiator is bound in the form of a copolymer, so that the ratio of the modified functional group in the modified initiator can be high and the solvent solubility can be excellent. Accordingly, when the above-described modified conjugated diene polymer is manufactured using the above-described modified initiator, all of the above-described properties can be more easily satisfied.

In addition, the above-described modified functional group-containing compound is a compound that can introduce a modified functional group to one end of a polymerized polymer by initiating polymerization and can form a modified initiator by being anionized through a reaction with an organometallic compound, and can be selected according to the target properties of the polymer, and for example, can be a hydrocarbon group-containing compound for improving solvent affinity, a heteroatom-containing compound for improving filler affinity, etc., and can be a compound including an unsaturated bond for smooth reaction with the organometallic compound.

As a specific example, the compound containing the modified functional group may be a compound represented by the following chemical formula 1.

The modification initiator according to the present invention is a compound capable of initiating polymerization and simultaneously introducing a functional group to one end of a polymer chain formed by polymerization. For example, the modification initiator may be a compound prepared by reacting an organometallic compound and an amine group-containing compound, and as an example, may be a compound represented by the following chemical formula 1.

[Chemical Formula 1]

In the above chemical formula 1,

R ₁ to R ₅ are each independently hydrogen; an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms, a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 5 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; or a heterocyclic group having 3 to 30 carbon atoms, and R ₆ is an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms, a heteroalkenyl group having 2 to 30 carbon atoms; A heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 5 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; or an alkylene group having 1 to 20 carbon atoms substituted or unsubstituted with a heterocyclic group having 3 to 30 carbon atoms, and X is a functional group represented by the following chemical formula 1a or chemical formula 1b,

[Chemical formula 1a]

In the above chemical formula 1a, R ₇ and R ₈ are each independently an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and R ₉ is hydrogen; an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 5 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; A heterocyclic group having 3 to 30 carbon atoms, Y is a N, O or S atom, and when Y is O or S, R ₉ does not exist,

[Chemical formula 1b]

In the above chemical formula 1b, R ₁₁ and R ₁₂ are each independently an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 5 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; a heterocyclic group having 3 to 30 carbon atoms.

Specifically, in the compound represented by the chemical formula 1, in the chemical formula 1, R ₁ to R ₅ are each independently hydrogen; an alkyl group having 1 to 10 carbon atoms; an alkenyl group having 2 to 10 carbon atoms; or an alkynyl group having 2 to 10 carbon atoms, R ₆ is an unsubstituted alkylene group having 1 to 10 carbon atoms, X is a functional group represented by the chemical formula 1a or the chemical formula 1b, and in the chemical formula 1a, R ₇ and R ₈ are each independently an unsubstituted alkylene group having 1 to 10 carbon atoms, R ₉ is an alkyl group having 1 to 10 carbon atoms; a cycloalkyl group having 5 to 20 carbon atoms; an aryl group having 6 to 20 carbon atoms; Or a heterocyclic group having 3 to 20 carbon atoms, Y is N, and in the chemical formula 1b, R ₁₁ and R ₁₂ may each independently be an alkyl group having 1 to 10 carbon atoms; a cycloalkyl group having 5 to 20 carbon atoms; an aryl group having 6 to 20 carbon atoms; or a heterocyclic group having 3 to 20 carbon atoms.

More specifically, the compound represented by the chemical formula 1 may be a compound represented by the following chemical formula 1-1 or chemical formula 1-2.

[Chemical Formula 1-1]

[Chemical Formula 1-2]

As another example, the compound containing the modified functional group may be a compound represented by the following chemical formula 2.

[Chemical formula 2]

In the above chemical formula 2,

R ₈ to R ₁₀ are each independently a hydrogen atom; a C 1 to 30 alkyl group; a C 2 to 30 alkenyl group; a C 2 to 30 alkynyl group; a C 1 to 30 heteroalkyl group, a C 2 to 30 heteroalkenyl group; a C 2 to 30 heteroalkynyl group; a C 3 to 30 cycloalkyl group; a C 6 to 30 aryl group; or a C 3 to 30 heterocyclic group, and R ₁₁ is a single bond; a C 1 to 20 alkylene group substituted or unsubstituted with a substituent; a C 3 to 20 cycloalkylene group substituted or unsubstituted with a substituent; Or an arylene group having 6 to 20 carbon atoms which is unsubstituted or substituted with a substituent, wherein the substituent is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and R ₁₂ is an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 3 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; a heterocyclic group having 3 to 30 carbon atoms; Or a functional group represented by the following chemical formula 2a or chemical formula 2b, p is an integer from 1 to 5, and at least one of R ₁₂ is a functional group represented by the following chemical formula 1a or chemical formula 1b, and when p is an integer from 2 to 5, multiple R ₁₂ may be the same or different from each other,

[Chemical formula 2a]

In the above chemical formula 2a, R _2a1 is an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a substituent; a cycloalkylene group having 3 to 20 carbon atoms which is unsubstituted or substituted with a substituent; or an arylene group having 6 to 20 carbon atoms which is unsubstituted or substituted with a substituent, wherein the substituent is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, R _2a2 and R _2a3 are each independently an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and R _2a4 is hydrogen; an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 3 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; a heterocyclic group having 3 to 30 carbon atoms, and X is a N, O or S atom, and when X is O or S, R ₉ is not present,

[Chemical formula 2b]

In the above chemical formula 2b,

R _2b1 is an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a substituent; a cycloalkylene group having 3 to 20 carbon atoms which is unsubstituted or substituted with a substituent; or an arylene group having 6 to 20 carbon atoms which is unsubstituted or substituted with a substituent, wherein the substituent is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and R _2b2 and R _2b3 are each independently an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 3 to 30 carbon atoms; An aryl group having 6 to 30 carbon atoms; a heterocyclic group having 3 to 30 carbon atoms.

Specifically, in the compound represented by the chemical formula 2, in the chemical formula 2, R ₈ to R ₁₀ are each independently hydrogen; an alkyl group having 1 to 10 carbon atoms; an alkenyl group having 2 to 10 carbon atoms; or an alkynyl group having 2 to 10 carbon atoms, R ₁₁ is a single bond; or an unsubstituted alkylene group having 1 to 10 carbon atoms, and R ₁₂ is an alkyl group having 1 to 10 carbon atoms; an alkenyl group having 2 to 10 carbon atoms; an alkynyl group having 2 to 10 carbon atoms; Or a functional group represented by the following chemical formula 2a or chemical formula 2b, wherein in the chemical formula 2a, R _2a1 is an unsubstituted alkylene group having 1 to 10 carbon atoms, R _2a2 and R _2a3 are each independently an unsubstituted alkylene group having 1 to 10 carbon atoms, R _2a4 is an alkyl group having 1 to 10 carbon atoms; a cycloalkyl group having 5 to 20 carbon atoms; an aryl group having 5 to 20 carbon atoms; or a heterocyclic group having 3 to 20 carbon atoms, and in the chemical formula 2b, R _b1 is an unsubstituted alkylene group having 1 to 10 carbon atoms, R _b2 and R _b3 are each independently an alkyl group having 1 to 10 carbon atoms; a cycloalkyl group having 5 to 20 carbon atoms; an aryl group having 5 to 20 carbon atoms; Or it may be a heterocyclic group having 3 to 20 carbon atoms.

More specifically, the compound represented by the chemical formula 2 may be a compound represented by the following chemical formulas 2-1 to 2-3.

[Chemical Formula 2-1]

[Chemical Formula 2-2]

[Chemical Formula 2-3]

In addition, the conjugated diene monomer used in the manufacture of the modification initiator may be the same substance as the conjugated diene monomer used in the polymerization, but may be at least one selected from the group consisting of, for example, 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-1,3-octadiene, isoprene, and 2-phenyl-1,3-butadiene.

The polymerization of the step (S1) may be, for example, anionic polymerization, and as a specific example, may be a living anionic polymerization having an anion active site at the polymerization terminal by a growth polymerization reaction by anion. In addition, the polymerization of the step (S1) may be temperature-elevated polymerization, isothermal polymerization, or isothermal polymerization (adiabatic polymerization), and the isothermal polymerization may mean a polymerization method including a step of polymerizing by the heat of reaction thereof without arbitrarily applying heat after introducing an organometallic compound, and the temperature-elevated polymerization may mean a polymerization method of increasing the temperature by arbitrarily applying heat after introducing the organometallic compound, and the isothermal polymerization may mean a polymerization method of maintaining the temperature of the polymerization product constant by adding heat to increase the heat or removing heat after introducing the organometallic compound.

In addition, 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, in which case there is an effect of preventing a gel from being formed on the wall of the reactor during long-term operation. The diene compound may be, for example, 1,2-butadiene.

The polymerization in the above (S1) step can be carried out, for example, at a temperature range of 100°C or less, 80°C or less, -20°C to 80°C, 0°C to 70°C, or 10°C to 70°C, and within this range, the conversion rate of the polymerization reaction can be increased, and the molecular weight distribution of the polymer can be controlled while satisfying the Mooney viscosity, Mooney relaxation rate, and phase difference index within the above-mentioned range, so that there is an excellent effect of improving the physical properties.

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

In addition, according to one embodiment of the present invention, the method for producing the modified conjugated diene polymer can be carried out by a continuous polymerization method in a plurality of reactors including two or more polymerization reactors and a modification reactor. As a specific example, the step (S1) can be carried out continuously in two or more polymerization reactors including the first reactor, and the number of the polymerization reactors can be flexibly determined according to the reaction conditions and environment. The continuous polymerization method can mean a reaction process of continuously supplying a reactant to a reactor and continuously discharging the generated reaction product. In the case of the continuous polymerization method, there is an effect of excellent productivity and processability, and excellent uniformity of the polymer produced.

In addition, according to one embodiment of the present invention, when continuously producing an active polymer in the polymerization reactor, the polymerization conversion rate in the first reactor can be 50% or less, 10% to 50%, or 20% to 50%, and within this range, after the polymerization reactor is initiated, side reactions occurring while the polymer is formed can be suppressed, thereby inducing a polymer having a linear structure during polymerization, and thus satisfying the Mooney viscosity, Mooney relaxation rate, and phase difference index within the above-mentioned ranges, so that there is an excellent effect of improving physical properties.

At this time, the polymerization conversion rate can be controlled according to the reaction temperature, reactor residence time, etc.

The above polymerization conversion rate can be determined, for example, by measuring the solid concentration of a polymer solution phase containing a polymer during polymerization of the polymer, and as a specific example, in order to secure the polymer solution, a cylindrical container is mounted at the outlet of each polymerization reactor, a certain amount of the polymer solution is filled into the cylindrical container, the cylindrical container is separated from the reactor, the weight (A) of the cylinder filled with the polymer solution is measured, the polymer solution filled in the cylindrical container is transferred to an aluminum container, for example, an aluminum dish, 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, the weight (C) of the dried polymer is measured, and the result may be calculated according to the following mathematical formula 1.

[Mathematical formula 1]

Meanwhile, the polymer polymerized in the first reactor can be sequentially transferred to a polymerization reactor before the denaturation reactor so that polymerization can proceed until the final polymerization conversion rate becomes 95% or higher, and after polymerization in the first reactor, the polymerization conversion rate of each reactor from the second reactor or the second reactor to the polymerization reactor before the denaturation reactor can be appropriately controlled for each reactor in order to control the molecular weight distribution.

Meanwhile, in the step (S1), when producing the active polymer, the residence time of the polymer in the first reactor can be 1 minute to 40 minutes, 1 minute to 30 minutes, or 5 minutes to 30 minutes, and within this range, the polymerization conversion rate can be easily controlled, and accordingly, the Mooney viscosity, Mooney relaxation rate, and phase difference index within the above-mentioned range can be satisfied, so that there is an excellent effect of improving the physical properties.

In the present invention, the term 'polymer' may mean an intermediate in the form of a polymer that is polymerized within each reactor during the execution of step (S1) prior to obtaining an active polymer or a modified conjugated diene polymer by completing step (S1) or step (S2), and may mean a polymer having a polymerization conversion rate of less than 90% that is polymerized within the reactor.

Meanwhile, the polymerization of the step (S1) may be carried out including a polar additive, and the polar additive may be added in a proportion of 0.001 g to 50 g, or 0.002 g to 0.1 g, based on 100 g of the total monomer. In another example, the polar additive may be added in a proportion of more than 0 g to 1 g, 0.01 g to 1 g, or 0.1 g to 0.9 g, based on 100 g of the total organometallic compound. When the polar additive is administered in the above range, the Mooney viscosity and Mooney relaxation rate in the above range can be satisfied.

The above polar additive may be, for example, at least one selected from the group consisting of tetrahydrofuran, ditetrahydrofurylpropane, diethyl ether, cyclopentyl ether, dipropyl ether, ethylene methyl ether, ethylene dimethyl ether, diethyl glycol, dimethyl ether, tert-butoxyethoxyethane, bis (3-dimethylaminoethyl) ether, (dimethylaminoethyl) ethyl ether, trimethylamine, triethylamine, tripropylamine, and tetramethylethylenediamine, and preferably 2,2-(di-2(tetrahydrofuryl)propane) or tetramethylethylenediamine.

According to one embodiment of the present invention, in the reaction of the step (S2), the modifier may be used in an amount of 0.01 mmol to 10 mmol based on 100 g of the total monomer. As 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 mol of the organometallic compound of the step (S1). The molar ratio of the modifier and the organometallic compound, and the amount of the modifier added relative to the monomer may affect the Mooney viscosity, Mooney relaxation rate, and phase difference index of the polymer to be actually manufactured, and therefore, it is preferable to select and apply an appropriate ratio within the above range as much as possible.

In addition, according to one embodiment of the present invention, the denaturant may be introduced into a denaturation reactor, and the step (S2) may be performed in the denaturation reactor. As another example, the denaturant may be introduced into a transfer unit for transferring the active polymer manufactured in the step (S1) to a denaturation reactor for performing the step (S2), and a reaction may proceed by mixing the active polymer and the denaturant within the transfer unit, wherein the reaction may be a denaturation reaction in which the denaturant is simply bonded to the active polymer, or a coupling reaction in which the active polymer is connected based on the denaturant, and as described above, the ratio of the denaturation reaction and the coupling reaction needs to be controlled, and this may affect Mooney viscosity, Mooney relaxation rate, and phase difference index.

In addition, the modifier may be a modifier for modifying the other terminal of the conjugated diene polymer, and a specific example thereof may be a silica affinity modifier. The silica affinity modifier may refer to a modifier containing a silica affinity functional group in a compound used as the modifier, and the silica affinity functional group may refer to a functional group having excellent affinity with a filler, particularly a silica-based filler, such that interaction between the silica-based filler and the functional group derived from the modifier is possible.

The above-mentioned modifier may be, for example, an alkoxy silane-based modifier, and a specific example thereof may be an alkoxy silane-based modifier containing one or more heteroatoms such as a nitrogen atom, an oxygen atom, or a sulfur atom. When the alkoxy silane-based modifier is used, modification may be carried out in a form in which one end of the active polymer is bonded to a silyl group through a substitution reaction between an anionic active site located at one end of the active polymer and an alkoxy group of the alkoxy silane-based modifier, and accordingly, the affinity for inorganic fillers, etc. is improved from the functional group derived from the modifier present at one end of the modified conjugated diene-based polymer, so that the mechanical properties of the rubber composition including the modified conjugated diene-based polymer are improved. In addition, when the alkoxy silane-based modifier contains a nitrogen atom, in addition to the effect derived from the silyl group, an additional property-boosting effect derived from the nitrogen atom can be expected.

According to one embodiment of the present invention, the modifier may include a compound represented by the following chemical formula 3.

[Chemical Formula 3]

In the above chemical formula 3, R _a1 is a single bond or an alkylene group having 1 to 10 carbon atoms, R _a2 and R _a3 are each independently an alkyl group having 1 to 10 carbon atoms, R _a5 may be a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a divalent, trivalent or tetravalent alkylsilyl group substituted with an alkyl group having 1 to 10 carbon atoms, or a heterocyclic group having 2 to 10 carbon atoms, and R _a4 is A single bond, an alkylene group having 1 to 10 carbon atoms, or -[R ⁴² O] _j -, wherein R ⁴² can be an alkylene group having 1 to 10 carbon atoms, n ₁ is an integer from 1 to 3, n ₂ is an integer from 0 to 2, but when n ₂ is 0, n ₁ is 1 or 2, and j can be an integer from 1 to 30.

As a specific example, in the chemical formula 3, R _a1 can be a single bond or an alkylene group having 1 to 5 carbon atoms, R _a2 and R _a3 can each independently be a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R _a5 can be a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a tetravalent alkylsilyl group substituted with an alkyl group having 1 to 5 carbon atoms, or a heterocyclic group having 2 to 5 carbon atoms, R _a4 can be a single bond, an alkylene group having 1 to 5 carbon atoms, or -[R ⁴² O] _j -, and R ⁴² can be an alkylene group having 1 to 5 carbon atoms.

In the above chemical formula 3, when R _a5 is a heterocyclic group, the heterocyclic group may be unsubstituted or substituted with a 3-substituted alkoxy silyl group, and when the heterocyclic group is substituted with a 3-substituted alkoxy silyl group, the 3-substituted alkoxy silyl group may be substituted by being connected to the heterocyclic group by an alkylene group having 1 to 10 carbon atoms, and the 3-substituted alkoxy silyl group may mean an alkoxy silyl group substituted with an alkoxy group having 1 to 10 carbon atoms. If the above R _a5 is a heterocyclic group substituted with an alkoxysilyl group, n ₁ and n ₂ may be adjusted so that the total number of alkoxy groups in the compound represented by the chemical formula 3 is 6 or less.

As a more specific example, the compound represented by the chemical formula 3 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-(diethoxy(methyl)silyl)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-(triethoxysilyl)propan-1-amine, N,N-bis(3-(diethoxy(methyl)silyl)propyl)-1,1,1-trimethlysilanamine, N,N-bis(3-(1H-imidazol-1-yl)propyl)-(triethoxysilyl)methan-1-amine, N-(3-(1H-1,2,4-triazole-1-yl)propyl)-3-(trimethoxysilyl)-N-(3-(trimethoxysilyl)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-pentaoxahexadecan-16-amine, N-(2,5,8,11,14-pentaoxahexadecan-16-yl)-N-(3-(triethoxysilyl)propyl)-2,5,8,11,14-pentaoxahexadecan-16-amine, and 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.

As another example, the modifier may include a compound represented by the following chemical formula 4.

[Chemical Formula 4]

In the above chemical formula 4,

R _c1 is hydrogen or an alkyl group having 1 to 10 carbon atoms,

R _c2 to R _c4 are independently an alkylene group having 1 to 10 carbon atoms,

R _c5 to R _c8 are independently an alkyl group having 1 to 10 carbon atoms,

A ₅ is or , wherein R _c9 to R _c12 are independently hydrogen or an alkyl group having 1 to 10 carbon atoms,

m ₁ and m ₂ are independently integers from 0 to 3, such that m ₁ +m ₂ ≥ 1.

Specifically, in the chemical formula 4, R _c1 is hydrogen or an alkyl group having 1 to 5 carbon atoms, R _c2 to R _c4 are each independently an alkylene group having 1 to 5 carbon atoms, R _c5 to R _c8 are each independently an alkyl group having 1 to 5 carbon atoms, and A ₅ is or , wherein R _c9 to R _c12 can be independently hydrogen or an alkyl group having 1 to 5 carbon atoms.

As a specific example, the compound represented by the chemical formula 4 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.

As another example, the modifier may include a compound represented by the following chemical formula 5.

[Chemical Formula 5]

In the above chemical formula 5, A ¹ and A ² can each independently be a divalent hydrocarbon group having 1 to 20 carbon atoms with or without an oxygen atom, R _b1 to R _b4 can each independently be a monovalent hydrocarbon group having 1 to 20 carbon atoms, L ¹ to L ⁴ are each independently a divalent, trivalent or tetravalent alkylsilyl group substituted with an alkyl group having 1 to 10 carbon atoms, or a monovalent hydrocarbon group having 1 to 20 carbon atoms, or L ¹ and L ² , L ³ and L ⁴ can be connected to each other to form a ring having 1 to 3 carbon atoms, and when L ¹ and L ² , L ³ and L ⁴ are connected to each other to form a ring, the formed ring can include 1 to 3 heteroatoms selected from the group consisting of N, O and S.

As a specific example, in the chemical formula 5, A ¹ and A ² can each independently be an alkylene group having 1 to 10 carbon atoms, R _b1 to R _b4 can each independently be an alkyl group having 1 to 10 carbon atoms, L ¹ to L ⁴ are each independently a tetravalent alkylsilyl 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 , L ³ and L ⁴ can be connected to each other to form a ring having 1 to 3 carbon atoms, and when L ¹ and L ² , L ³ and L ⁴ are connected to each other to form a ring, the formed ring can include 1 to 3 heteroatoms selected from the group consisting of N, O and S.

As a more specific example, the compound represented by the chemical formula 5 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), 3,3'-(1,1,3,3-tetrapropoxydisiloxane-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-dimpropylpropan-1-amine)(3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-dimpropylpropan-1-amine), 3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine)(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-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), 3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,N-dipropylpropan-1-amine)(3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,N-dipropylpropan-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)(3,3'-(1,1,3,3-tetraethoxydisiloxane-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'-(1,1,3,3-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,N-dimethylmethan-1-amine)(3,3'-(1,1,3,3-tetrapropoxydisiloxane-1,3-diyl)bis(N,N-dimethylmethan-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-dimethylmethan-1-amine), 3,3'-(1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(N,N-dipropylmethan-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-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(propan-3,1-diyl))bis(1,1,1-trimethyl-N-phenylsilanamine), N,N'-((1,1,3,3-tetraethoxydisiloxane-1,3-diyl)bis(propan-3,1-diyl))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)propyl)-1,1,3,3-tetramethoxydisiloxane), It may be one selected from the group consisting of 1,3-bis(3-(1H-imidazol-1-yl)propyl)-1,1,3,3-tetraethoxydisiloxane, and 1,3-bis(3-(1H-imidazol-1-yl)propyl)-1,1,3,3-tetrapropoxydisiloxane.

As another example, the modifier may include a compound represented by the following chemical formula 6.

[Chemical formula 6]

In the above chemical formula 6, R ²² and R ²³ are each independently an alkylene group having 1 to 20 carbon atoms, or -R ²⁸ [OR ²⁹ ] _f -, R ²⁴ to R ²⁷ can 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 can each independently be an alkylene group having 1 to 20 carbon atoms, R ⁴⁷ and R ⁴⁸ can each independently be a divalent hydrocarbon group having 1 to 6 carbon atoms, d and e are each independently 0 or an integer selected from 1 to 3, wherein d+e is an integer greater than or equal to 1, and f can be an integer of 1 to 30.

Specifically, in the chemical formula 6, R ²² and R ²³ can each independently be an alkylene group having 1 to 10 carbon atoms, or -R ²⁸ [OR ²⁹ ] _f -, R ²⁴ to R ²⁷ can each independently be an alkyl group having 1 to 10 carbon atoms, R ²⁸ and R ²⁹ can each independently be an alkylene group having 1 to 10 carbon atoms, d and e are each independently 0, or an integer selected from 1 to 3, wherein d+e can be an integer greater than or equal to 1, and f can be an integer selected from 1 to 30.

More specifically, the compound represented by the chemical formula 6 may be a compound represented by the following chemical formula 6a, chemical formula 6b, or chemical formula 6c.

[Chemical formula 6a]

[Chemical formula 6b]

[Chemical formula 6c]

In the above chemical formulas 6a, 6b and 6c, R ²² to R ²⁷ , d and e are as described above.

As a more specific example, the compound represented by the chemical formula 6 is 1,4-bis(3-(3-(triethoxysilyl)propoxy)propyl)piperazine, 1,4-bis(3-(triethoxysilyl)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-(ethoxydimethyl)propyl)-4-(3-(triethoxysilyl)methyl)piperazine, 1-(3-(ethoxydimethyl)methyl)-4-(3-(triethoxysilyl)methyl)piperazine, 1,3-bis(3-(triethoxysilyl)propyl)imidazolidine, 1,3-bis(3-(dimethoxyethylsilyl)propyl)imidazolidine, 1,3-bis(3-(trimethoxysilyl)propyl)hexahydropyrimidine, 1,3-bis(3-(triethoxysilyl)propyl)hexahydropyrimidine, and It may be one selected from the group consisting of 1,3-bis(3-(tributoxysilyl)propyl)-1,2,3,4-tetrahydropyrimidine.

As another example, the modifier may include a compound represented by the following chemical formula 7.

[Chemical formula 7]

In the above chemical formula 7, R ³⁰ can be a monovalent hydrocarbon group having 1 to 30 carbon atoms, R ³¹ to R ³³ can each independently be an alkylene group having 1 to 10 carbon atoms, R ³⁴ to R ³⁷ can each independently be an alkyl group having 1 to 10 carbon atoms, g and h are each independently 0 or an integer selected from 1 to 3, and g+h can be an integer greater than or equal to 1.

As another example, the modifier may include a compound represented by the following chemical formula 8.

[Chemical formula 8]

In the chemical formula 8, A ³ and A ⁴ can each independently be an alkylene group having 1 to 10 carbon atoms, R ³⁸ to R ⁴¹ can each independently be an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and i can be an integer selected from 1 to 30.

As another example, the modifier may include a compound represented by the following chemical formula 9.

[Chemical formula 9]

In the above chemical formula 9, R ⁴³ , R ⁴⁵ and R ⁴⁶ can each independently be an alkyl group having 1 to 10 carbon atoms, R ⁴⁴ can be an alkylene group having 1 to 10 carbon atoms, and k can be an integer selected from 1 to 4.

As a more specific example, the compound represented by the chemical formula 9 is 8,8-dibutyl-3,13-dimethoxy-3,13-dimethyl-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane, It may be one selected from the group consisting of 8,8-dimetyl-3,13-dimethoxy-3,13-dimethyl-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane, and 8,8-dibutyl-3,3,13,13-tetramethoxy-2,14-dioxa-7,9-dithia-3,13-disila-8-stannapentadecane.

According to the present invention, a rubber composition comprising the above-described modified conjugated diene polymer is provided.

The above rubber composition may contain the modified conjugated diene polymer in an amount of 10 wt% or more, 10 wt% to 100 wt%, or 20 wt% to 90 wt%, and within this range, the composition has excellent mechanical properties such as tensile strength and wear resistance, and excellent balance between each property.

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

The above rubber component may be, for example, natural rubber or synthetic rubber, and specific examples thereof include natural rubber (NR) including cis-1,4-polyisoprene; modified natural rubber such as epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber, which are modified or refined from the above general natural rubber; It can be a synthetic rubber such as styrene-butadiene copolymer (SBR), polybutadiene (BR), polyisoprene (IR), butyl rubber (IIR), ethylene-propylene copolymer, polyisobutylene-co-isoprene, neoprene, poly(ethylene-co-propylene), poly(styrene-co-butadiene), poly(styrene-co-isoprene), poly(styrene-co-isoprene-co-butadiene), poly(isoprene-co-butadiene), poly(ethylene-co-propylene-co-diene), polysulfide rubber, acrylic rubber, urethane rubber, silicone rubber, epichlorohydrin rubber, halogenated butyl rubber, and any one of these or a mixture of two or more thereof can be used.

The above rubber composition may contain, for example, 0.1 to 200 parts by weight, or 10 to 120 parts by weight, of a filler based on 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, or colloidal silica, and preferably wet silica, which has the most excellent effect of improving fracture characteristics and achieving wet grip properties. In addition, the rubber composition may further contain a carbon-based filler, if necessary.

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, and 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-Triethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, 2-Triethoxysilylethyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-Trimethoxysilylpropylbenzothiazolyltetrasulfide, 3-Triethoxysilylpropylbenzolyltetrasulfide, 3-Triethoxysilylpropylmethacrylate monosulfide, 3-Trimethoxysilylpropylmethacrylate monosulfide, bis(3-diethoxymethylsilylpropyl)tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, or dimethoxymethylsilylpropylbenzothiazolyltetrasulfide, and the like, and any one or a mixture of two or more of these may be used. Preferably, considering the effect of improving reinforcing properties, it may be bis(3-triethoxysilylpropyl)polysulfide or 3-trimethoxysilylpropylbenzothiazyl tetrasulfide.

In addition, since the rubber composition according to one embodiment of the present invention uses a modified conjugated diene polymer having a functional group having high affinity for silica introduced into an active site as a rubber component, the amount of the silane coupling agent can be reduced compared to the usual case, and accordingly, the silane coupling agent can be used in an amount of 1 to 20 parts by weight, or 5 to 15 parts by weight, based on 100 parts by weight of silica, and within this range, the effect as a coupling agent is sufficiently exhibited while also having the effect of preventing gelation of the rubber component.

The rubber composition according to one embodiment of the present invention may be sulfur crosslinkable and may further include a vulcanizing agent. The vulcanizing agent may be specifically sulfur powder and may be included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the rubber component, and within this range, the vulcanized rubber composition has the effect of securing the necessary elastic modulus and strength while exhibiting excellent fuel efficiency.

The rubber composition according to one embodiment of the present invention may further include, in addition to the above-described components, various additives commonly used in the rubber industry, specifically, a vulcanization accelerator, a process oil, a plasticizer, an anti-aging agent, a scorch inhibitor, zinc white, stearic acid, a thermosetting resin, or a thermoplastic resin.

The above-mentioned vulcanization accelerator may be, for example, a thiazole-based compound such as M(2-mercaptobenzothiazole), DM(dibenzothiazyl disulfide), CZ(N-cyclohexyl-2-benzothiazyl sulfenamide), or a guanidine-based compound such as DPG (diphenyl guanidine), and may be included in an amount of 0.1 to 5 parts by weight per 100 parts by weight of the rubber component.

The above process oil acts as a softener in the rubber composition, and may be, for example, a paraffinic, naphthenic, or aromatic compound. When considering tensile strength and wear resistance, an aromatic process oil may be used, and when considering hysteresis loss and low-temperature characteristics, a naphthenic or paraffinic process oil may be used. The above process oil may be included in an amount of, for example, 100 parts by weight or less with respect to 100 parts by weight of the rubber component, and within this range, there is an effect of preventing a decrease in the tensile strength and low heat generation (low fuel consumption) of the vulcanized rubber.

The above-mentioned 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.

The rubber composition according to one embodiment of the present invention can be obtained by mixing using a mixer such as a Banbury mixer, a roll mixer, or an internal mixer according to the above compounding prescription, and a rubber composition having low heat generation and excellent wear resistance can be obtained by a vulcanization process after molding processing.

Accordingly, the rubber composition can be useful in the manufacture of various components of a tire, such as a tire tread, undertread, sidewall, carcass coating rubber, belt coating rubber, bead filler, squeegee, or bead coating rubber, or various industrial rubber products, such as an anti-vibration rubber, belt conveyor, and hose.

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

The above tire may include a tire or tire tread.

Hereinafter, the present invention will be described in detail by way of examples in order to specifically explain the present invention. However, the examples according to the present invention may be modified in various different forms, 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 in order to more completely explain the present invention to a person having average knowledge in the art.

Manufacturing example 1

Three 4 L vacuum-dried stainless steel pressure vessels were prepared. Cyclohexane, a compound represented by the following chemical formula 1-1, and tetramethylethylenediamine were added to the first pressure vessel to prepare a first reaction solution. At the same time, 2.0 M n-butyllithium and cyclohexane in a liquid state were added to the second pressure vessel to prepare a second reaction solution. In addition, 1,3-butadiene and cyclohexane were added to the third pressure vessel to prepare a third reaction solution. While the pressure of each pressure vessel was maintained at 7 bar, the first reaction solution, the second reaction solution, and the third reaction solution were each injected into the continuous reactor using a mass flow meter, and the temperature of the reactor was maintained at -10°C and the internal pressure at 3 bar, and the residence time inside the reactor was adjusted to be less than 10 minutes to carry out the reaction. At this time, the molar ratio of the compound represented by the chemical formula 1-1, n-butyllithium, and 1,3-butadiene was 1.5:1:1. Afterwards, the reaction was terminated to obtain a denaturation initiator.

[Chemical Formula 1-1]

Manufacturing example 2

Three 4 L vacuum-dried stainless steel pressure vessels were prepared. Cyclohexane, a compound represented by the following chemical formula 2-3, and tetramethylethylenediamine were added to the first pressure vessel to prepare a first reaction solution. At the same time, 2.0 M n-butyllithium and cyclohexane in liquid form were added to the second pressure vessel to prepare a second reaction solution. In addition, 1,3-butadiene and cyclohexane were added to the third pressure vessel to prepare a third reaction solution. While the pressure of each pressure vessel was maintained at 7 bar, the first reaction solution, the second reaction solution, and the third reaction solution were each injected into the continuous reactor using a mass flow meter, and the temperature of the reactor was maintained at -10°C and the internal pressure at 3 bar, and the residence time inside the reactor was adjusted to be less than 10 minutes to carry out the reaction. At this time, the molar ratio of the compound represented by the chemical formula 2-3, n-butyllithium, and 1,3-butadiene was 1.5:1:1. Afterwards, the reaction was terminated to obtain a denaturation initiator.

[Chemical Formula 2-3]

Example 1

Into one reactor of three continuously stirred tank reactors (CSTR), a 1,3-butadiene solution containing 60 wt% of 1,3-butadiene dissolved in n-hexane was injected at a rate of 16.7 kg/h, a 53.6 kg/h n-hexane solution, a 60 g/h 1,2-butadiene solution containing 2.0 wt% of 1,2-butadiene dissolved in n-hexane, a 20.8 g/h polar additive solution containing 1.2 wt% of tetramethylethylenediamine dissolved in n-hexane as a polar additive, and a 270 g/h denaturation initiator solution containing 10 wt% of the denaturation initiator prepared in Preparation Example 2 dissolved in n-hexane as a denaturation initiator. At this time, the temperature inside the reactor was maintained at 50℃, and when the polymerization conversion rate reached 45%, the polymer was transferred from the first reactor to the second reactor through the transfer pipe.

At this time, the temperature of the second reactor was maintained at 65°C, and when the polymerization conversion rate was 95% or higher, the polymer was transferred from the second reactor to the third reactor through the transfer pipe.

The polymer was transferred from the second reactor to the third reactor, and a solution containing 20 wt% of 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine) as a modifier was introduced into the third reactor at a rate of 85 g/h, and the temperature of the third reactor was maintained at 65°C.

Thereafter, a solution of IR1520 (BASF) dissolved at 30 wt% as an antioxidant was injected at a rate of 167 g/h into the polymerization solution discharged from the third reactor and stirred. The resulting polymer was placed in hot water heated by steam and stirred to remove the solvent, and then roll-dried to remove the remaining solvent and water, thereby producing a double-ended butadiene polymer. The analysis results for the double-ended butadiene polymer thus produced are shown in Table 1 below.

Example 2

In Example 1, a butadiene polymer modified at both ends was manufactured in the same manner as in Example 1, except that the modification initiator manufactured in Manufacturing Example 1 was used instead of the modification initiator manufactured in Manufacturing Example 2.

Comparative Example 1

Into one reactor of three continuously stirred tank reactors (CSTR), a 1,3-butadiene solution containing 60 wt% 1,3-butadiene in n-hexane was injected at a rate of 16.7 kg/h, a 53.6 kg/h n-hexane solution, a 60 g/h 1,2-butadiene solution containing 2.0 wt% 1,2-butadiene in n-hexane, a 20.8 g/h polar additive solution containing 1.2 wt% tetramethylethylenediamine as a polar additive, and a 65 g/h n-butyllithium solution containing 10 wt% n-butyllithium were injected. At this time, the temperature inside the reactor was maintained at 55°C, and when the polymerization conversion rate reached 48%, the polymer was transferred from the first reactor to the second reactor through the transfer pipe.

At this time, the temperature of the second reactor was maintained at 65°C, and when the polymerization conversion rate was 95% or higher, the polymer was transferred from the second reactor to the third reactor through the transfer pipe.

The polymer was transferred from the second reactor to the third reactor, and a solution containing 20 wt% dimethyl dichlorosilane as a coupling agent was introduced into the third reactor at a rate of 25 g/h, while the temperature of the third reactor was maintained at 65°C.

Thereafter, a 30 wt% IR1520 (BASF) solution was dissolved as an antioxidant in the polymerization solution discharged from the third reactor at a rate of 167 g/h and stirred. The resulting polymer was placed in hot water heated by steam and stirred to remove the solvent, and then roll-dried to remove the remaining solvent and water, thereby producing an unmodified butadiene polymer. The analysis results for the unmodified butadiene polymer thus produced are shown in Table 1 below.

Comparative Example 2

Among three continuously stirred tank reactors (CSTR), one reactor was injected with a 1,3-butadiene solution containing 60 wt% of 1,3-butadiene dissolved in n-hexane at a rate of 16.7 kg/h, a 1,2-butadiene solution containing 2.0 wt% of 1,2-butadiene dissolved in n-hexane at a rate of 53.6 kg/h, a 60 g/h solution of a polar additive containing 1.2 wt% of tetramethylethylenediamine dissolved in n-hexane as a polar additive at a rate of 20.8 g/h, and a denaturation initiator solution containing 10 wt% of the denaturation initiator prepared in Preparation Example 2 dissolved in n-hexane as a denaturation initiator at a rate of 320 g/h. At this time, the temperature inside the reactor was maintained at 50℃, and when the polymerization conversion rate reached 45%, the polymer was transferred from the first reactor to the second reactor through the transfer pipe.

At this time, the temperature of the second reactor was maintained at 65°C, and when the polymerization conversion rate was 95% or higher, the polymer was transferred from the second reactor to the third reactor through the transfer pipe.

The polymer was transferred from the second reactor to the third reactor, and a solution containing 20 wt% of 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine) as a modifier was introduced into the third reactor at a rate of 85 g/h, and the temperature of the third reactor was maintained at 65°C.

Thereafter, a solution of IR1520 (BASF) dissolved at 30 wt% as an antioxidant was injected at a rate of 167 g/h into the polymerization solution discharged from the third reactor and stirred. The resulting polymer was placed in hot water heated by steam and stirred to remove the solvent, and then roll-dried to remove the remaining solvent and water, thereby producing a double-ended butadiene polymer. The analysis results for the double-ended butadiene polymer thus produced are shown in Table 1 below.

Comparative Example 3

In Example 1, instead of using 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine) as a modifier, a solution of tris(3-(trimethoxysilyl)propyl)amine dissolved in n-hexane at 20 wt% was added to the third reactor at a rate of 99 g/h to perform the modification reaction, and the same procedure as in Example 1 was carried out to produce a butadiene polymer modified at both ends.

Comparative Example 4

In Example 1, instead of 3,3'-(1,1,3,3-tetramethoxydisiloxane-1,3-diyl)bis(N,N-diethylpropan-1-amine) as a modifier, a solution of 3.3-(piperazine-1,4-diyl)bis(N,N-bis(3-(triethoxysilyl)propyl)propan-1-amine)) dissolved in n-hexane at 20 wt% was injected into the third reactor at a rate of 164 g/h to perform the modification reaction, and the same procedure as in Example 1 was carried out to produce a butadiene polymer modified at both ends.

Experimental Example 1

For each modified or unmodified conjugated diene polymer manufactured in the above examples and comparative examples, the weight average molecular weight (Mw, X10 ³ g/mol), number average molecular weight (Mn, X10 ³ g/mol), molecular weight distribution (PDI, MWD), Mooney viscosity (MV), Mooney relaxation rate (-S/R), content of Si atoms and N atoms, and phase difference index were measured, respectively, and the results are shown in Table 1 below.

1) Weight average molecular weight (Mw), number average molecular weight (Mn) and molecular weight distribution (MWD)

The above weight average molecular weight (Mw) and number average molecular weight (Mn) were measured through GPC (gel permeation chromatography) analysis, and the molecular weight distribution (PDI, MWD, Mw/Mn) was calculated from the measured molecular weights. Specifically, the GPC was performed using a combination of two PLgel Olexis (Polymer Laboratories) columns and one PLgel mixed-C (Polymer Laboratories) column, and PS (polystyrene) was used as the GPC standard material when calculating the molecular weight. The GPC measurement solvent was prepared by mixing 2 wt% of an amine compound into tetrahydrofuran.

2) Mooney viscosity (MV) and Mooney relaxation rate (-S/R)

The above Mooney viscosity (MV, (ML1+4, @100℃ MU) was measured using MV-2000 (ALPHA Technologies) at 100℃, Rotor Speed 2±0.02 rpm, Large Rotor. The sample used was left at room temperature (23±3℃) for more than 30 minutes, then 27±3 g was collected and filled into the die cavity, and the Platen was operated for measurement for 4 minutes. After measuring the Mooney viscosity, the slope value of the Mooney viscosity change that appears when the torque is released was measured to obtain the Mooney relaxation rate.

3) Content of Si atoms

The above Si content was measured using an inductively coupled plasma optical emission spectrometer (ICP-OES; Optima 7300DV) as an ICP analysis method. When using the inductively coupled plasma optical emission spectrometer, about 0.7 g of the sample was placed in a platinum crucible, about 1 mL of concentrated sulfuric acid (98 wt%, Electronic grade) was added, heated at 300°C for 3 hours, and the sample was annealed in an electric furnace (Thermo Scientific, Lindberg Blue M) using the following program of steps 1 to 3,

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)

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

4) N atom content

The N content may be measured, for example, by the NSX analysis method, and the NSX analysis method may be measured using a trace nitrogen quantitative analyzer (NSX-2100H).

For example, in case of using the above trace nitrogen quantitative analyzer, the trace nitrogen quantitative analyzer (Auto sampler, Horizontal furnace, PMT & Nitrogen detector) was turned on and the carrier gas flow rates were set to 250 ml/min for Ar, 350 ml/min for _O2 , and 300 ml/min for ozonizer, and the heater was set to 800℃, and then the analyzer was stabilized for about 3 hours. After the analyzer was stabilized, a calibration curve was created with a Nitrogen standard (AccuStandard S-22750-01-5 ml) for a calibration curve range of 5 ppm, 10 ppm, 50 ppm, 100 ppm, and 500 ppm, and the Area corresponding to each concentration was obtained, and a straight line was created using the ratio of the Area to the concentration. Thereafter, a ceramic boat containing 20 mg of the sample was placed on the Auto sampler of the analyzer and measured to obtain the area. The N content was calculated using the area of the obtained sample and the above calibration curve.

5) Phase difference index

This represents the Tan δ value at 0.1 Hz in a Tan δ graph against frequency (Hz) obtained by measuring under the conditions of 160℃ and 7% strain (0.5 degree) using a SCARABAEUS INSTRUMENTS SYSTEMS (SIS) V-50 Rubber Process Analyzer of SCARABAEUS Co., Ltd. Specifically, about 6 g of a polymer was prepared, placed on a disk, and measured using the analyzer under the above conditions to obtain a Tan δ graph against frequency (Hz), and the Tan δ value at 0.1 Hz was read and expressed as a phase difference index.

division GPC MV -S/R Si
(ppm) N
(ppm) Phase difference index Mw(X10 ³ g/mol) Mn(X10 ³ g/mol) MWD Example 1 480 300 1.60 50 0.9 190 200 1.00 Example 2 510 320 1.59 53 1.0 210 230 1.05 Comparative Example 1 450 290 1.55 48 1.1 20 - 1.10 Comparative Example 2 270 170 1.59 35 1.8 250 260 1.30 Comparative Example 3 610 340 1.79 62 0.3 230 180 0.40 Comparative Example 4 640 360 1.78 65 0.3 220 230 0.35

Example 3

Using a semi-batch mixer equipped with a temperature control device, 80 parts by weight of the conjugated diene polymer with both ends modified according to Example 1, 20 parts by weight of natural rubber, 70 parts by weight of silica (filler), and 5.8 parts by weight of a silane coupling agent (Si-69, Evonik) were mixed with 100 parts by weight of the rubber component to prepare a rubber composition.

Example 4

In Example 3, a rubber composition was manufactured in the same manner as in Example 3, except that the conjugated diene polymer having both ends modified as manufactured in Example 2 was used instead of the conjugated diene polymer having both ends modified as manufactured in Example 1.

Comparative Example 5

In Example 3, a rubber composition was manufactured in the same manner as in Example 4, except that the unmodified conjugated diene polymer manufactured in Comparative Example 1 was included instead of the both-end modified conjugated diene polymer manufactured in Example 1.

Comparative Example 6

In Example 3, a rubber composition was manufactured in the same manner as in Example 4, except that the modified conjugated diene polymer manufactured in Comparative Example 2 was included instead of the both-end modified conjugated diene polymer manufactured in Example 1.

Comparative Example 7

In Example 3, a rubber composition was manufactured in the same manner as in Example 4, except that the conjugated diene polymer having both ends modified in Comparative Example 3 was used instead of the conjugated diene polymer having both ends modified in Example 1.

Comparative Example 8

In Example 3, a rubber composition was manufactured in the same manner as in Example 4, except that the conjugated diene polymer having both ends modified in Comparative Example 4 was used instead of the conjugated diene polymer having both ends modified in Example 1.

Experimental example 2

After manufacturing rubber specimens using each rubber composition, which is a one-stage mixing composition manufactured in the above examples and comparative examples, the tensile strength, 300% modulus, rolling resistance characteristics, and wear resistance were measured using the following methods. The results are shown in Table 2 below.

To each of the above rubber compositions, 1.5 parts by weight of sulfur, 2.0 parts by weight of a rubber accelerator (DPD (diphenyl guanine)), and 1.75 parts by weight of a vulcanization accelerator (CZ (N-cytohexyl-2-benzothiazyl sulfenamide)) were added and mixed at a temperature of 100°C or lower to obtain a compound. Thereafter, a rubber specimen was manufactured through a curing process at 160°C for 20 minutes. At this time, the above weight parts are expressed based on 100 parts by weight of the rubber component when manufacturing the rubber composition.

1) Tensile properties

Tensile properties were measured by manufacturing each test piece according to the tensile test method of ASTM 412, and measuring the tensile strength at break and the tensile stress at 300% elongation (300% modulus) of the test piece. Specifically, the tensile properties were measured at room temperature at a speed of 50 cm/min using a Universal Test Machin 4204 (Instron) tensile tester.

2) Cloud resistance characteristics

The cloud resistance characteristics were confirmed through viscoelastic characteristic analysis.

Viscoelastic properties were measured using a dynamic mechanical analyzer (GABO Corporation) in Film Tension mode at a frequency of 10 Hz and at each measurement temperature (-60℃ to 60℃) to determine the tan δ value for dynamic deformation. At this time, the lower the tan δ value at high temperature 60℃, the less hysteresis loss and the better the rolling resistance characteristics (fuel efficiency). However, the result values in Table 2 below were expressed as an index (Index, %) using the following mathematical expression 2 with the measurement result values of Comparative Example 1 as the reference value, so a higher numerical value indicates better.

[Mathematical formula 2]

Index(%)=(reference value/measurement value)X100

3) Wear resistance (DIN wear test)

For each rubber specimen, a DIN abrasion test was performed according to ASTM D5963, and the DIN wt loss index (loss volume index: ARIA (Abration resistance index, Method A)) was expressed based on the measured value of Comparative Example 1. A higher value indicates better performance.

As shown in Table 2 above, Examples 3 and 4 according to one embodiment of the present invention showed excellent tensile properties compared to Comparative Examples 5 to 8, while Tan δ and wear resistance at 60°C were significantly improved at the same time.

At this time, Examples 3 and 4 include the modified conjugated diene polymers of Examples 1 and 2 in which the Mooney viscosity, the Mooney relaxation rate, the Si and N contents, and the phase difference index are controlled within the specific ranges presented in the present invention, and Comparative Examples 5 to 8 include the modified conjugated diene polymers of Comparative Examples 1 to 4 in which at least one of the Mooney viscosity, the Mooney relaxation rate, the Si and N contents, and the phase difference index is not controlled within the specific ranges presented.

The above results mean that the modified conjugated diene polymer of the present invention has Mooney viscosity, Mooney relaxation rate, Si and N contents, and phase difference index controlled within specific ranges, and thus can be applied to a rubber composition to improve rolling resistance and wear resistance properties without deteriorating the tensile properties of the rubber composition.

Claims (10)

A double-ended polymer having a functional group derived from a modification initiator at one end and a functional group derived from a modification agent at the other end,
The above modification initiator is prepared by reacting a compound containing a modification functional group, an organometallic compound, and a conjugated diene monomer.
The compound containing the above modified functional group is a compound represented by the following chemical formula 1 or chemical formula 2,
The functional group derived from the above modifier is a functional group derived from an alkoxysilane type modifier.
A modified conjugated diene polymer satisfying the conditions i) to v) below:
i) Repeating unit derived from aromatic vinyl monomer: 0 wt%,
ⅱ) Mooney viscosity measured under ASTM D1646 conditions: 40 to 100,
ⅲ) Phase difference index at 0.1 Hz measured at 160℃: 0.65 or more,
ⅳ) Si atom and N atom content: 50 ppm or more based on the total weight of the polymer, and
ⅴ) Mooney relaxation rate measured at 100℃: 0.5 to 1.0,
[Chemical Formula 1]

In the above chemical formula 1,
R ₁ to R ₅ are each independently hydrogen; an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms, a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 5 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; or a heterocyclic group having 3 to 30 carbon atoms, and R ₆ is an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms, a heteroalkenyl group having 2 to 30 carbon atoms; A heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 5 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; or an alkylene group having 1 to 20 carbon atoms substituted or unsubstituted with a heterocyclic group having 3 to 30 carbon atoms, and X is a functional group represented by the following chemical formula 1a or chemical formula 1b,
[Chemical formula 1a]

In the above chemical formula 1a, R ₇ and R ₈ are each independently an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and R ₉ is hydrogen; an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 5 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; A heterocyclic group having 3 to 30 carbon atoms, Y is a N, O or S atom, and when Y is O or S, R ₉ does not exist,
[Chemical formula 1b]

In the above chemical formula 1b, R ₁₁ and R ₁₂ are each independently an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 5 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; a heterocyclic group having 3 to 30 carbon atoms,
[Chemical formula 2]

In the above chemical formula 2,
R ₈ to R ₁₀ are each independently a hydrogen atom; a C 1 to 30 alkyl group; a C 2 to 30 alkenyl group; a C 2 to 30 alkynyl group; a C 1 to 30 heteroalkyl group, a C 2 to 30 heteroalkenyl group; a C 2 to 30 heteroalkynyl group; a C 3 to 30 cycloalkyl group; a C 6 to 30 aryl group; or a C 3 to 30 heterocyclic group, and R ₁₁ is a single bond; a C 1 to 20 alkylene group substituted or unsubstituted with a substituent; a C 3 to 20 cycloalkylene group substituted or unsubstituted with a substituent; Or an arylene group having 6 to 20 carbon atoms which is unsubstituted or substituted with a substituent, wherein the substituent is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and R ₁₂ is an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 3 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; a heterocyclic group having 3 to 30 carbon atoms; Or a functional group represented by the following chemical formula 2a or chemical formula 2b, p is an integer from 1 to 5, and at least one of R ₁₂ is a functional group represented by the following chemical formula 1a or chemical formula 1b, and when p is an integer from 2 to 5, multiple R ₁₂ may be the same or different from each other,
[Chemical formula 2a]

In the above chemical formula 2a, R _2a1 is an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a substituent; a cycloalkylene group having 3 to 20 carbon atoms which is unsubstituted or substituted with a substituent; or an arylene group having 6 to 20 carbon atoms which is unsubstituted or substituted with a substituent, wherein the substituent is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, R _2a2 and R _2a3 are each independently an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and R _2a4 is hydrogen; an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 3 to 30 carbon atoms; an aryl group having 6 to 30 carbon atoms; a heterocyclic group having 3 to 30 carbon atoms, and X is a N, O or S atom, and when X is O or S, R ₉ is not present,
[Chemical formula 2b]

In the above chemical formula 2b,
R _2b1 is an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a substituent; a cycloalkylene group having 3 to 20 carbon atoms which is unsubstituted or substituted with a substituent; or an arylene group having 6 to 20 carbon atoms which is unsubstituted or substituted with a substituent, wherein the substituent is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and R _2b2 and R _2b3 are each independently an alkyl group having 1 to 30 carbon atoms; an alkenyl group having 2 to 30 carbon atoms; an alkynyl group having 2 to 30 carbon atoms; a heteroalkyl group having 1 to 30 carbon atoms; a heteroalkenyl group having 2 to 30 carbon atoms; a heteroalkynyl group having 2 to 30 carbon atoms; a cycloalkyl group having 3 to 30 carbon atoms; An aryl group having 6 to 30 carbon atoms; a heterocyclic group having 3 to 30 carbon atoms.
delete In the first paragraph,
A modified conjugated diene polymer having a phase difference index of 0.65 to 5 at 0.1 Hz measured at 160°C.
In the first paragraph,
A modified conjugated diene polymer having a number average molecular weight (Mn) of 1,000 to 2,000,000 g/mol and a weight average molecular weight (Mw) of 1,000 to 3,000,000 g/mol.
In the first paragraph,
A modified conjugated diene polymer having a molecular weight distribution of 1.5 to 3.5.
delete A rubber composition comprising a modified conjugated diene polymer according to claim 1 and a filler.
In Article 7,
A rubber composition wherein the above filler is a silica-based filler or a carbon black-based filler.
In Article 7,
A rubber composition comprising 0.1 to 200 parts by weight of a filler per 100 parts by weight of the modified conjugated diene polymer.
In Article 7,
A rubber composition comprising a vulcanizing agent.