KR20220040260A - Modified conjugated diene polymer, preparation method thereof and rubber composition comprising the same - Google Patents

Abstract

The present invention relates to a modified conjugated diene-based polymer with improved compounding properties due to excellent affinity with a filler, a preparation method thereof, and a rubber composition. The modified conjugated diene-based polymer can have an excellent affinity with a filler by bonding a modified agent-derived functional group represented by chemical formula 1 to a polymer chain side chain, and thus can be applied to the rubber composition to have excellent processability and compounding properties such as tensile, wear resistance, and viscoelasticity.

Description

Modified conjugated diene-based polymer, manufacturing method thereof, and rubber composition comprising the same

The present invention relates to a modified conjugated diene-based polymer having improved compounding properties due to excellent affinity with a filler, a method for preparing the same, and a rubber composition comprising the same.

In response to the recent demand for fuel economy reduction in automobiles, a conjugated diene-based polymer having low running resistance, excellent abrasion resistance and tensile properties, and adjustment stability typified by wet skid resistance is required as a rubber material for tires.

In order to reduce the running resistance of the tire, there is a method of reducing the hysteresis loss of the vulcanized rubber, and rebound elasticity of 50°C to 80°C, tan δ, Goodrich heat, etc. are used as evaluation indicators of the vulcanized rubber. That is, a rubber material having a large rebound elasticity at the above temperature or a small tan δ or Goodrich heat generation is preferable.

As a rubber material having a small hysteresis loss, natural rubber, polyisoprene rubber, polybutadiene rubber, etc. are known, but these have a problem of low wet skid resistance. Accordingly, recently, conjugated diene-based (co)polymers such as styrene-butadiene rubber (hereinafter referred to as SBR) or butadiene rubber (hereinafter referred to as BR) have been manufactured by emulsion polymerization or solution polymerization and are used as rubber for tires. .

When the BR or SBR is used as a rubber material for a tire, a filler such as silica or carbon black is usually blended together to obtain the required physical properties of the tire. However, the affinity of the BR or SBR with the filler is not good, so there is a problem in that physical properties including abrasion resistance, crack resistance or workability are rather deteriorated.

Accordingly, as a method for improving the dispersibility of SBR and fillers such as silica or carbon black, a method of modifying the polymerization active site of a conjugated diene-based polymer obtained by anionic polymerization using organolithium with a functional group that can interact with the filler has been proposed. . For example, a method of modifying the polymerizable end of a conjugated diene-based polymer with a tin-based compound, introducing an amino group, or modifying with an alkoxysilane derivative has been proposed.

In addition, in a living polymer obtained by coordination polymerization using a catalyst composition containing a lanthanum-based rare earth element compound as a method for increasing the dispersibility of BR and fillers such as silica or carbon black, the living active end is treated with a specific modifier A method of denaturation has been developed. However, in the case of the terminal-modified polymer, the affinity with the filler is improved, and compounding properties, such as tensile properties and viscoelastic properties, are improved, but on the other hand, compounding processability is greatly reduced, so there is a problem in poor processability.

In addition, when preparing a rubber composition by mixing SBR or BR with a filler such as silica or carbon black, a coupling agent having a functional group such as a silane group, an amine group, or an azo group is mixed together to increase the affinity between the SBR or BR and the filler. An attempt was made to improve the compounding properties and compounding processability by increasing the dispersibility of the filler, but the compounding property improvement effect was not obtained.

Therefore, there is a need for a method capable of improving processability while having excellent compounding properties when manufacturing SBR or BR.

JP 5172663 B2

The present invention has been devised to solve the problems of the prior art, and an object of the present invention is to provide a modified conjugated diene-based polymer having excellent processability and improved compounding properties.

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

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

In order to solve the above problems, the present invention provides a modified conjugated diene-based polymer comprising a functional group derived from a modifier represented by the following formula (1):

[Formula 1]

In Formula 1,

R ₁ , R ₂ , and R ₃ are each independently an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms,

a is 0 to 2.

In addition, the present invention comprises the steps of preparing an active polymer by polymerizing a conjugated diene-based monomer in the presence of a catalyst composition comprising a neodymium compound in a hydrocarbon solvent (step 1); And it provides a method for producing the modified conjugated diene-based polymer comprising the step (step 2) of reacting the active polymer with a modifier represented by Formula 1:

[Formula 1]

In Formula 1,

R ₁ , R ₂ , and R ₃ are each independently an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms,

a is 0 to 2.

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

The modified conjugated diene-based polymer according to the present invention may have excellent affinity with a filler because the functional group derived from the modifier represented by Formula 1 is bonded to the polymer chain side chain, and thus it is applied to a rubber composition to have excellent processability and tensile properties and compounding properties such as viscoelastic properties.

In addition, the method for producing the modified conjugated diene-based polymer according to the present invention modifies the active polymer using the modifier represented by Formula 1, thereby causing a reaction between a double bond in the active polymer and an azo group in the modifier. It is possible to easily prepare a modified conjugated diene-based polymer having a structure to which is bonded.

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

The terms or words used in the present specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor may properly define the concept of the term in order to best describe his invention. Based on the principle that there is, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

The term 'substitution' used in the present invention may mean that hydrogen of a functional group, atomic group, or compound is substituted with a specific substituent, and when hydrogen of a functional group, atomic group, or compound is substituted with a specific substituent, the functional group, atomic group, or compound is present One or two or more plural substituents may be present depending on the number of hydrogens to be used. In addition, when a plurality of substituents exist, each substituent may be the same as or different from each other.

The term 'monovalent hydrocarbon group' used in the present invention refers to a monovalent substituent derived from a hydrocarbon group, for example, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkyl group having one or more unsaturated bonds, an aryl group, etc. It may represent a monovalent atomic group in which carbon and hydrogen are bonded, and the monovalent atomic group may have a linear or branched structure depending on the structure of the bond.

The term 'divalent hydrocarbon group' used in the present invention refers to a divalent substituent derived from a hydrocarbon group, for example, an alkylene group, an alkenylene group, an alkynylene group, a cycloalkylene group, or a cycloalkyl containing one or more unsaturated bonds. It may represent a divalent atomic group in which carbon and hydrogen are bonded, such as a lene group and an arylene group, and the divalent atomic group may have a linear or branched structure depending on the structure of the bond.

The term 'heterohydrocarbon group' used in the present invention is a substituent in which at least two or more different atoms among atoms constituting the hydrocarbon group exist, for example, a hydrocarbon group containing one or more heteroatoms among N, S and O. It may mean a hydrocarbon group. .

The term 'alkyl group' used in the present invention may mean a monovalent aliphatic saturated hydrocarbon, and linear alkyl groups such as methyl, ethyl, propyl and butyl and isopropyl, sec-butyl ), tert-butyl, and neo-pentyl, such as branched alkyl groups, may be included.

The term 'cycloalkyl group' used in the present invention may mean a cyclic saturated hydrocarbon.

The term 'aryl group' used in the present invention may mean a cyclic aromatic hydrocarbon, and also a monocyclic aromatic hydrocarbon in which one ring is formed or a polycyclic aromatic hydrocarbon in which two or more rings are bonded. It may mean including all aromatic hydrocarbons.

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

The terms 'derived unit' and 'derived functional group' used in the present invention may indicate a component, structure, or substance itself derived from a substance.

The present invention provides a modified conjugated diene-based polymer having excellent compounding processability and excellent compounding properties such as tensile properties, abrasion resistance and viscoelastic properties.

Specifically, the modified conjugated diene-based polymer according to an embodiment of the present invention is characterized in that it includes a functional group derived from a modifier represented by the following formula (1).

[Formula 1]

In Formula 1,

R ₁ , R ₂ , and R ₃ are each independently an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms,

a is 0 to 2.

The modifier according to the present invention may be the compound represented by Formula 1 itself, or may include other compounds capable of modifying the conjugated diene-based polymer together with the compound represented by Formula 1 above.

In Formula 1, R ₁ , R ₂ , and R ₃ are each independently an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms.

Specifically, R ₁ , R ₂ , and R ₃ may each independently be an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or a cycloalkyl group having 3 to 12 carbon atoms.

More specifically, R ₁ , R ₂ , and R ₃ may each independently be a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms.

More specifically, R ₁ , R ₂ , and R ₃ may be a methyl group, an ethyl group, or a 2-ethylhelyl group.

In Formula 1, a is 0 to 2. More specifically, a is 0 or 1.

As a specific example, the modifier represented by Formula 1 may be at least one selected from the group consisting of compounds represented by Formulas 1-1 to 1-3 below.

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

The modifier according to an embodiment of the present invention includes an ester group, an azo group, a carbonyl group, and an amine group in a molecule.

The azo group can introduce a functional group derived from a denaturant into a side chain in the polymer main chain by exhibiting high reactivity with a double bond in the main chain of the polymer. there is.

The ester group can increase the affinity for the polymerization solvent to increase the solubility of the modifier, and thereby facilitate the denaturation reaction, thereby improving the denaturation rate. In addition, the ester group can improve the stability of the modifier by reducing the electron density of the azo group.

The carbonyl group may serve to improve the stability of the modifier by lowering the electron density through electron resonance with an azo group.

The amine group may act to increase affinity with a filler by acting with a carboxyl group present on the surface of carbon black to improve physical properties.

As such, the modifier has a structure capable of maximizing the compounding properties of the modified conjugated diene-based polymer, and thus a modified conjugated diene-based polymer having an excellent balance of mechanical properties such as abrasion resistance and processability of the rubber composition can be efficiently produced.

Meanwhile, in the modified conjugated diene-based polymer according to an embodiment of the present invention, the polymer may include a modifier-derived functional group in a side chain. That is, the functional group derived from the modifier may be bonded to the main chain constituting the polymer as a side chain, and may have a structure represented by the following Chemical Formula 2 as a specific example.

[Formula 2]

In Formula 2, R ₁ , to R ₃ and a are as defined in Formula 1, and n and m represent the ratio of units constituting the polymer, and n+m may be 100 mol%.

Specifically, the modifier represented by Chemical Formula 1 according to an embodiment of the present invention includes an azo group, a double bond in the polymer, that is, a double bond in the main chain composed of a unit derived from a conjugated diene-based monomer, and the The azo group reacts and a functional group derived from a modifier is bonded as a side chain of the main chain to modify the conjugated diene-based polymer.

In addition, the polymer according to an embodiment of the present invention may include a functional group derived from a modifier represented by Chemical Formula 1 at at least one end.

That is, the modified conjugated diene-based polymer according to an embodiment of the present invention may have a structure that includes a modifier-derived functional group in a side chain, and also includes a modifier-derived functional group at at least one terminal.

In addition, the modified conjugated diene-based polymer may be a butadiene homopolymer such as polybutadiene, or a diene-based copolymer such as a butadiene-isoprene copolymer.

As a specific example, the modified conjugated diene-based polymer may contain 80 to 100% by weight of 1,3-butadiene monomer-derived units, and 20% by weight or less of other conjugated diene-based monomer-derived units that are optionally copolymerizable with 1,3-butadiene. There is an effect that the content of 1,4-cis bonds in the polymer is not lowered within the above range. In this case, the 1,3-butadiene monomer includes 1,3-butadiene or derivatives thereof, such as 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, or 2-ethyl-1,3-butadiene. and other conjugated diene-based monomers copolymerizable with 1,3-butadiene include 2-methyl-1,3-pentadiene, 1,3-pentadiene, 3-methyl-1,3-pentadiene, 4 -methyl-1,3-pentadiene, 1,3-hexadiene, or 2,4-hexadiene may be mentioned, and any one or two or more compounds of these may be used.

In addition, the modified conjugated diene-based polymer according to an embodiment of the present invention may be a neodymium-catalyzed modified conjugated diene-based polymer. That is, the modified conjugated diene-based polymer may be a conjugated diene-based polymer including an organometallic moiety activated from a catalyst composition including a neodymium compound.

In addition, the modified conjugated diene-based polymer according to an embodiment of the present invention may have a Mooney viscosity (MV) of 20 or more and 100 or less at 100° C., specifically, 30 or more and 80 or less, 35 or more and 75 or less. or 40 or more and 70 or less.

The modified conjugated diene-based polymer according to the present invention may have excellent processability by having a Mooney viscosity within the aforementioned range.

In the present invention, the Mooney viscosity was measured using a Mooney viscometer, for example, a Large Rotor of Monsanto's MV2000E at 100° C. and a rotor speed of 2±0.02 rpm. Specifically, after leaving the polymer at room temperature (23±5° C.) for more than 30 minutes, 27±3 g was collected, filled in the die cavity, and the Mooney viscosity was measured while applying a torque by operating a platen.

In addition, the modified conjugated diene-based polymer may have a molecular weight distribution (Mw/Mn) of 2.0 to 3.5, and more specifically, a molecular weight distribution of 2.5 to 3.5, 2.5 to 3.2, or 2.6 to 3.0.

In the present invention, the molecular weight distribution of the modified conjugated diene-based polymer may be calculated from the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn). In this case, the number average molecular weight (Mn) is a common average of individual polymer molecular weights calculated by measuring the molecular weights of n polymer molecules, obtaining the sum of these molecular weights, and dividing by n, and the weight average molecular weight (Mw) is the polymer The molecular weight distribution of the composition is shown. All molecular weight averages can be expressed in grams per mole (g/mol). In addition, the weight average molecular weight and the number average molecular weight may mean a polystyrene equivalent molecular weight analyzed by gel permeation chromatography (GPC), respectively.

The modified conjugated diene-based polymer according to an embodiment of the present invention may satisfy the molecular weight distribution conditions described above and have a weight average molecular weight (Mw) of 3 X 10 ⁵ to 1.5 X 10 ⁶ g/mol, and a number average The molecular weight (Mn) may be 1.0 X 10 ⁵ to 5.0 X 10 ⁵ g/mol, and when applied to a rubber composition within this range, it has excellent tensile properties and excellent processability, resulting in improved workability of the rubber composition. It is easy, there is an excellent effect of the mechanical properties and the balance of physical properties of the rubber composition. The weight average molecular weight may be, for example, 5 X 10 ⁵ to 1.2 X 10 ⁶ g/mol, or 5 X 10 ⁵ to 8 X 10 ⁵ g/mol, and the number average molecular weight is, for example, 1.5 X 10 ⁵ to 3.5 X 10 ⁵ g/mol, or 2.0 X 10 ⁵ to 2.7 X 10 ⁵ g/mol.

More specifically, when the modified conjugated diene-based polymer according to an embodiment of the present invention simultaneously meets the weight average molecular weight (Mw) and number average molecular weight conditions along with the molecular weight distribution described above, when applied to the rubber composition, It has excellent tensile properties, viscoelasticity and workability, and an excellent balance of physical properties between them.

In addition, the conjugated diene-based polymer may have a cis-1,4 bond content of 95% or more, more specifically 98% or more, of the conjugated diene part measured by Fourier transform infrared spectroscopy (FT-IR). Accordingly, when applied to the rubber composition, the abrasion resistance, crack resistance and ozone resistance of the rubber composition may be improved.

In addition, in the modified conjugated diene-based polymer, the vinyl content of the conjugated diene part measured by Fourier transform infrared spectroscopy may be 5% or less, more specifically, 2% or less. When the vinyl content in the polymer exceeds 5%, there is a fear that the abrasion resistance, crack resistance, and ozone resistance of the rubber composition including the same may be deteriorated.

Here, the cis-1,4 bond content and the vinyl content in the polymer by the Fourier transform infrared spectroscopy (FT-IR) are the conjugated diene-based polymers prepared at a concentration of 5 mg/mL using carbon disulfide in the same cell as a blank. After measuring the FT-IR transmittance spectrum of the carbon disulfide solution, the maximum peak value near 1130 cm ^-1 of the measurement spectrum (a, baseline), and the minimum peak value near 967 cm ^-1 indicating trans-1,4 bond (b), each content was obtained using the minimum peak value (c) near 911 cm ^-1 representing the vinyl bond, and the minimum peak value (d) near 736 cm ^-1 representing the cis-1,4 bond will be.

In addition, the present invention provides a method for producing the modified conjugated diene-based polymer.

The preparation method according to an embodiment of the present invention comprises the steps of preparing an active polymer by polymerizing a conjugated diene-based monomer in the presence of a catalyst composition containing a neodymium compound in a hydrocarbon solvent (step 1); and reacting the active polymer with a modifier represented by the following formula (1) (step 2).

[Formula 1]

In Formula 1,

R ₁ to R ₃ and a are as defined above.

Step 1 is a step of preparing an active polymer including an organometallic moiety by polymerizing the conjugated diene-based monomer, and may be performed by polymerizing the conjugated diene-based monomer in the presence of a catalyst composition including a neodymium compound in a hydrocarbon solvent.

In the present invention, in the active polymer containing the organometallic moiety, the organometallic moiety is an activated organometallic moiety at the end of the conjugated diene-based polymer (an activated organometallic moiety at the end of the molecular chain), and an activated organometallic moiety in the main chain. It may be an activated organometallic moiety in a moiety or a side chain (side chain), and among them, when an activated organometallic moiety of a conjugated diene-based polymer is obtained by anionic polymerization or coordination anion polymerization, the organometallic moiety is an activated organometallic moiety at the terminal It may indicate a region.

The conjugated diene-based monomer is not particularly limited, for example, 1,3-butadiene, isoprene, 1,3-pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl The group consisting of -1,3-butadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene and 2,4-hexadiene, etc. It may be at least one selected from

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

The catalyst composition may be used in an amount such that the neodymium compound is 0.1 mmol to 0.5 mmol based on 100 g of the total of the conjugated diene-based monomers, specifically, the neodymium compound is the amount of the neodymium compound based on 100 g of the total of the conjugated diene-based monomers It may be used in an amount such that 0.1 mmol to 0.4 mmol, more specifically, 0.1 mmol to 0.25 mmol.

The neodymium compound is a carboxylate salt thereof (eg, neodymium acetate, neodymium acrylate, neodymium methacrylate, neodymium gluconate, neodymium citrate, neodymium fumarate, neodymium lactate, neodymium maleate, neodymium oxalate, neodymium 2 -ethylhexanoate, neodymium neodecanoate, etc.); Organophosphates (e.g., neodymium dibutyl phosphate, neodymium dipentyl phosphate, neodymium dihexyl phosphate, neodymium diheptyl phosphate, neodymium dioctyl phosphate, neodymium bis(1-methyl heptyl) phosphate, neodymium bis(2-ethylhexyl) phosphate, or neodymium didecyl phosphate, etc.); organic phosphonates (e.g., neodymium butyl phosphonate, neodymium pentyl phosphonate, neodymium hexyl phosphonate, neodymium heptyl phosphonate, neodymium octyl phosphonate, neodymium (1-methyl heptyl) phosphonate, neodymium (2-ethylhexyl) phosphonate, neodymium disyl phosphonate, neodymium dodecyl phosphonate, or neodymium octadecyl phosphonate); organic phosphinates (e.g., neodymium butylphosphinate, neodymium pentylphosphinate, neodymium hexyl phosphinate, neodymium heptyl phosphinate, neodymium octyl phosphinate, neodymium (1-methyl heptyl) phosphinate, or neodymium (2-ethylhexyl) phosphinate, etc.); carbamates (eg, neodymium dimethyl carbamate, neodymium diethyl carbamate, neodymium diisopropyl carbamate, neodymium dibutyl carbamate, or neodymium dibenzyl carbamate, etc.); dithiocarbamate (eg, neodymium dimethyldithiocarbamate, neodymium diethyldithiocarbamate, neodymium diisopropyl dithiocarbamate, or neodymium dibutyldithiocarbamate); xanthogenates (eg, neodymium methyl xanthogen, neodymium ethyl xanthogen, neodymium isopropyl xanthogen, neodymium butyl xanthogen, or neodymium benzyl xanthogen, etc.); β-diketonate (eg, neodymium acetylacetonate, neodymium trifluoroacetyl acetonate, neodymium hexafluoroacetyl acetonate or neodymium benzoyl acetonate, etc.); alkoxides or allyloxides (eg, neodymium methoxide, neodymium ethoxide, neodymium isopropoxide, neodymium phenoxide or neodymium nonyl phenoxide, etc.); halides or pseudohalides (such as neodymium fluoride, neodymium chloride, neodymium bromide, neodymium iodide, neodymium cyanide, neodymium cyanate, neodymium thiocyanate, or neodymium azide); oxyhalides (eg, neodymium oxyfluoride, neodymium oxy chloride, or neodymium oxy bromide, etc.); or an organic neodymium containing compound comprising one or more elemental neodymium-carbon bonds (eg, Cp ₃ Nd, Cp ₂ NdR, Cp ₂ NdCl, CpNdCl ₂ , CpNd(cyclooctatetraene), (C ₅ Me ₅ ) ₂ ) NdR, NdR ₃ , Nd(allyl) ₃ , or Nd(allyl) ₂ Cl, etc., wherein R is a hydrocarbyl group), and the like, may include any one or a mixture of two or more thereof.

The neodymium compound may be a compound represented by the following formula (3).

[Formula 3]

In Formula 3, Ra to Rc are each independently hydrogen or an alkyl group having 1 to 12 carbon atoms, provided that Ra to Rc are not all hydrogen at the same time.

More specifically, the neodymium compound is Nd(2-ethylhexanoate) ₃ , Nd(2,2-dimethyl decanoate) ₃ , Nd(2,2-diethyl decanoate) ₃ , Nd(2, 2-dipropyl decanoate) ₃ , Nd(2,2-dibutyl decanoate) ₃ , Nd(2,2-dihexyl decanoate) ₃ , Nd(2,2-dioctyl decanoate) ₃ , Nd(2-ethyl-2-propyl decanoate) ₃ , Nd(2-ethyl-2-butyl decanoate) ₃ , Nd(2-ethyl-2-hexyl decanoate) ₃ , Nd(2 -Propyl-2-butyl decanoate) ₃ , Nd(2-propyl-2-hexyl decanoate) ₃ , Nd(2-propyl-2-isopropyl decanoate) ₃ , Nd(2-butyl-2 -Hexyl decanoate) ₃ , Nd (2-hexyl-2-octyl decanoate) ₃ , Nd (2,2-diethyl octanoate) ₃ , Nd (2,2-dipropyl octanoate) ₃ , Nd(2,2-dibutyl octanoate) ₃ , Nd(2,2-dihexyl octanoate) ₃ , Nd(2-ethyl-2-propyl octanoate) ₃ , Nd(2-ethyl- 2-hexyl octanoate) ₃ , Nd(2,2-diethyl nonanoate) ₃ , Nd(2,2-dipropylnonanoate) ₃ , Nd(2,2-dibutyl nonanoate) ₃ 1 selected from the group consisting of , Nd(2,2-dihexyl nonanoate) ₃ , Nd(2-ethyl-2-propyl nonanoate) ₃ and Nd(2-ethyl-2-hexyl nonanoate) ₃ It may be more than a species.

In addition, as another example, considering the excellent solubility in solvents, conversion to catalytically active species, and thus the catalytic activity improvement effect without concerns about oligomerization, the neodymium compound is more specifically, in Formula 3, Ra is the number of carbon atoms. It is an alkyl group of 4 to 12, and Rb and Rc are each independently hydrogen or an alkyl group having 2 to 8 carbon atoms, provided that Rb and Rc are not hydrogen at the same time.

As a more specific example, in Formula 3, Ra is an alkyl group having 6 to 8 carbon atoms, Rb and Rc may each independently be hydrogen or an alkyl group having 2 to 6 carbon atoms, wherein Rb and Rc may not be hydrogen at the same time and specific examples thereof include Nd (2,2-diethyl decanoate) ₃ , Nd (2,2-dipropyl decanoate) ₃ , Nd (2,2-dibutyl decanoate) ₃ , Nd ( 2,2-dihexyl decanoate) ₃ , Nd(2,2-dioctyl decanoate) ₃ , Nd(2-ethyl-2-propyl decanoate) ₃ , Nd(2-ethyl-2-butyl) Decanoate) ₃ , Nd(2-ethyl-2-hexyl decanoate) ₃ , Nd(2-propyl-2-butyl decanoate) ₃ , Nd(2-propyl-2-hexyl decanoate) ₃ , Nd(2-propyl-2-isopropyl decanoate) ₃ , Nd(2-butyl-2-hexyl decanoate) ₃ , Nd(2-hexyl-2-octyl decanoate) ₃ , Nd(2 -t-Butyl decanoate) ₃ , Nd(2,2-diethyl octanoate) ₃ , Nd(2,2-dipropyl octanoate) ₃ , Nd(2,2-dibutyl octanoate) ₃ , Nd(2,2-dihexyl octanoate) ₃ , Nd(2-ethyl-2-propyl octanoate) ₃ , Nd(2-ethyl-2-hexyl octanoate) ₃ , Nd(2, 2-diethyl nonanoate) ₃ , Nd(2,2-dipropyl nonanoate) ₃ , Nd(2,2-dibutyl nonanoate) ₃ , Nd(2,2-dihexyl nonanoate) ₃ , Nd(2-ethyl-2-propyl nonanoate) ₃ and Nd(2-ethyl-2-hexyl nonanoate) ₃ may be at least one selected from the group consisting of, among which the neodymium-based compound is Nd (2,2-diethyl decanoate) ₃ , Nd (2,2-dipropyl decanoate) ₃ , Nd (2,2-dibutyl decanoate) ₃ , Nd (2,2-dihexyl de Canoate) ₃ , and Nd(2,2-dioctyl decanoate) ₃ It may be at least one selected from the group consisting of.

More specifically, in Formula 3, Ra is an alkyl group having 6 to 8 carbon atoms, and Rb and Rc may each independently be an alkyl group having 2 to 6 carbon atoms.

As such, the neodymium-based compound represented by Formula 3 includes a carboxylate ligand including an alkyl group having various lengths of 2 or more carbon atoms as a substituent at the α (alpha) position, thereby inducing a steric change around the neodymium central metal compound It is possible to block the clumping phenomenon of the liver, and thus, there is an effect of suppressing oligomerization. In addition, such a neodymium-based compound has a high solubility in a solvent, and a ratio of neodymium located in a central portion having difficulty in conversion to a catalytically active species is reduced, thereby increasing the conversion rate to a catalytically active species.

In addition, the solubility of the neodymium compound according to an embodiment of the present invention may be about 4 g or more per 6 g of the non-polar solvent at room temperature (25 ℃).

In the present invention, the solubility of the neodymium-based compound refers to the degree of clear dissolution without turbidity, and by exhibiting such high solubility, excellent catalytic activity can be exhibited.

In addition, the neodymium compound according to an embodiment of the present invention may be used in the form of a reactant with a Lewis base. This reactant has the effect of improving the solubility of the neodymium compound in the solvent by the Lewis base and storing it in a stable state for a long period of time. The Lewis base may be used, for example, in a ratio of 30 moles or less, or 1 to 10 moles per mole of neodymium element. The Lewis base may be, for example, acetylacetone, tetrahydrofuran, pyridine, N,N-dimethylformamide, thiophene, diphenyl ether, triethylamine, an organophosphorus compound, or monovalent or divalent alcohol.

Meanwhile, the catalyst composition may further include at least one of an alkylating agent, a halide, and a conjugated diene-based monomer together with the neodymium compound.

That is, the catalyst composition according to an embodiment of the present invention may include a neodymium compound and further include at least one of an alkylating agent, a halide, and a conjugated diene-based monomer.

Hereinafter, the (a) alkylating agent, (b) halide, and (c) conjugated diene-based monomer will be separately described.

(a) alkylating agent

The alkylating agent is an organometallic compound capable of transferring a hydrocarbyl group to another metal, and may serve as a co-catalyst. The alkylating agent may be used without particular limitation as long as it is used as an alkylating agent in the production of a diene-based polymer, for example, it is soluble in a polymerization solvent, such as an organoaluminum compound, an organomagnesium compound, or an organolithium compound, and forms a metal-carbon bond. It may be an organometallic compound containing.

Specifically, the organoaluminum compound includes trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-t-butylaluminum, and tripentylaluminum. Alkyl aluminum, such as aluminum, trihexyl aluminum, tricyclohexyl aluminum, and trioctylaluminum; diethylaluminum hydride, di-n-propylaluminum hydride, diisopropylaluminum hydride, di-n-butylaluminum hydride, diisobutylaluminum hydride (DIBAH), di-n-octylaluminum hydride, Diphenylaluminum hydride, di-p-tolylaluminum hydride, dibenzylaluminum hydride, phenylethylaluminum hydride, phenyl-n-propylaluminum hydride, phenylisopropylaluminum hydride, phenyl-n-butylaluminum hydride Ride, phenylisobutylaluminum hydride, phenyl-n-octylaluminum hydride, p-tolylethylaluminum hydride, p-tolyl-n-propylaluminum hydride, p-tolylisopropylaluminum hydride, p-tolyl- n-butylaluminum hydride, p-tolylisobutylaluminum hydride, p-tolyl-n-octylaluminum hydride, benzylethylaluminum hydride, benzyl-n-propylaluminum hydride, benzylisopropylaluminum hydride, benzyl dihydrocarbylaluminum hydride such as -n-butylaluminum hydride, benzylisobutylaluminum hydride or benzyl-n-octylaluminum hydride; Hydrocarbylaluminum dihydride such as ethylaluminum dihydride, n-propylaluminum dihydride, isopropylaluminum dihydride, n-butylaluminum dihydride, isobutylaluminum dihydride or n-octylaluminum dihydride, etc. A hydride etc. are mentioned. Examples of the organic magnesium compound include alkyl magnesium compounds such as diethyl magnesium, di-n-propyl magnesium, diisopropyl magnesium, dibutyl magnesium, dihexyl magnesium, diphenyl magnesium, or dibenzyl magnesium, and the like. Examples of the organolithium compound include alkyl lithium compounds such as n-butyllithium.

In addition, the organoaluminum compound may be aluminoxane.

The aluminoxane may be prepared by reacting a trihydrocarbyl aluminum-based compound with water, and specifically, may be a linear aluminoxane of the following Chemical Formula 4a or a cyclic aluminoxane of the following Chemical Formula 4b.

[Formula 4a]

[Formula 4b]

In Formulas 4a and 4b, R is a monovalent organic group bonded to an aluminum atom through a carbon atom, and may be a hydrocarbyl group, and x and y are each independently an integer of 1 or more, specifically 1 to 100 , more specifically, may be an integer of 2 to 50.

More specifically, the aluminoxane is methylaluminoxane (MAO), modified methylaluminoxane (MMAO), ethylaluminoxane, n-propylaluminoxane, isopropylaluminoxane, butylaluminoxane, isobutylaluminoxane, n -pentyl aluminoxane, neopentyl aluminoxane, n-hexyl aluminoxane, n-octylaluminoxane, 2-ethylhexyl aluminoxane, cyclohexyl aluminoxane, 1-methylcyclopentyl aluminoxane, phenyl aluminoxane or 2,6- dimethylphenyl aluminoxane and the like, and any one or a mixture of two or more thereof may be used.

In addition, the modified methylaluminoxane may be a compound in which the methyl group of methylaluminoxane is substituted with a modifying group (R), specifically, a hydrocarbon group having 2 to 20 carbon atoms, specifically, a compound represented by the following Chemical Formula 5.

[Formula 5]

In Formula 5, R is as defined above, and m and n may be each independently an integer of 2 or more. In addition, in Formula 5, Me represents a methyl group.

Specifically, in Formula 5, R is an alkyl group having 2 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, a cycloalkenyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, It may be an arylalkyl group having 7 to 20 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms, an allyl group or an alkynyl group having 2 to 20 carbon atoms, and more specifically, an ethyl group, isobutyl group, hexyl group or octyl group having 2 carbon atoms. to 10, and more specifically, may be an isobutyl group.

More specifically, the modified methylaluminoxane may be obtained by substituting about 50 to 90 mol% of the methyl group of methylaluminoxane with the above-described hydrocarbon group. When the content of the substituted hydrocarbon group in the modified methylaluminoxane is within the above range, the catalytic activity may be increased by promoting alkylation.

Such modified methylaluminoxane may be prepared according to a conventional method, and specifically may be prepared using trimethylaluminum and alkylaluminum other than trimethylaluminum. In this case, the alkyl aluminum may be triisobutyl aluminum, triethyl aluminum, trihexyl aluminum or trioctyla aluminum, and any one or a mixture of two or more thereof may be used.

In addition, the catalyst composition according to an embodiment of the present invention may include the alkylating agent in a molar ratio of 1 to 200, specifically 1 to 100 molar ratio, more specifically 3 to 20 molar ratio with respect to 1 mole of the neodymium compound. there is. If the alkylating agent is included in an amount exceeding 200 molar ratio, it is not easy to control the catalytic reaction during the preparation of the polymer, and there is a risk that an excessive amount of the alkylating agent may cause side reactions.

(b) halides

The halide is not particularly limited, but may include, for example, a simple halogen, an interhalogen compound, a hydrogen halide, a group halide, a non-metal halide, a metal halide, or an organometal halide, and any of these One or a mixture of two or more may be used. Among them, any one or a mixture of two or more selected from the group consisting of organic halides, metal halides, and organometallic halides may be used as the halide in consideration of the excellent effect of improving catalytic activity and thus improving reactivity.

Examples of the halogen alone include fluorine, chlorine, bromine or iodine.

Examples of the interhalogen compound include iodine monochloride, iodine monobromide, iodine trichloride, iodine pentafluoride, iodine monofluoride or iodine trifluoride.

In addition, the hydrogen halide may include hydrogen fluoride, hydrogen chloride, hydrogen bromide or hydrogen iodide.

In addition, as the organic halide, t-butyl chloride (t-BuCl), t-butyl bromide, allyl chloride, allyl bromide, benzyl chloride, benzyl bromide, chloro-di-phenylmethane, bromo-di-phenylmethane, tri Phenylmethyl chloride, triphenyl methyl bromide, benzylidene chloride, benzylidene bromide, methyltrichlorosilane, phenyltrichlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, trimethylchlorosilane (TMSCl), benzoyl chloride, benzoyl bromide, propyi Onyl chloride, propionyl bromide, methyl chloroformate, methyl bromoformate, iodomethane, diiodomethane, triiodomethane (also called 'iodoform'), tetraiodomethane, 1-io Dopropane, 2-iodopropane, 1,3-diiodopropane, t-butyliodide, 2,2-dimethyl-1-iodopropane (also called 'neopentyl iodide'), allyl iodine Odide, iodobenzene, benzyl iodide, diphenylmethyl iodide, triphenylmethyl iodide, benzylidene iodide (also called 'benzal iodide'), trimethylsilyl iodide, triethyl Silyl iodide, triphenylsilyl iodide, dimethyldiiodosilane, diethyldiiodosilane, diphenyldiiodosilane, methyltriiodosilane, ethyltriiodosilane, phenyltriiodosilane, benzoyl iodide, propionyl iodide or methyl iodoformate; and the like.

In addition, as the non-metal halide, phosphorus trichloride, phosphorus tribromide, phosphorus pentachloride, phosphorus oxychloride, phosphorus oxybromide, boron trifluoride, boron trichloride, boron tribromide, silicon tetrafluoride, silicon tetrachloride (SiCl4), silicon tetrabromide, Arsenic trichloride, arsenic tribromide, selenium tetrachloride, selenium tetrabromide, tellurium tetrachloride, tellurium tetrabromide, silicon tetraiodide, arsenic triiodide, tellurium tetraiodide, boron triiodide, phosphorus triiodide, phosphorus oxyiodide or selenium tetraiodide can be heard

In addition, as the metal halide, tin tetrachloride, tin tetrabromide, aluminum trichloride, aluminum tribromide, antimony trichloride, antimony pentachloride, antimony tribromide, aluminum trifluoride, gallium trichloride, gallium tribromide, gallium trifluoride, indium trichloride, Indium tribromide, indium trifluoride, titanium tetrachloride, titanium tetrabromide, zinc dichloride, zinc dibromide, zinc difluoride, aluminum triiodide, gallium triiodide, indium triiodide, titanium tetraiodide, zinc iodide, tetraiodide germanium, tin tetraiodide, tin iodide, antimony triiodide, or magnesium iodide.

In addition, as the organometallic halide, dimethyl aluminum chloride, diethyl aluminum chloride, dimethyl aluminum bromide, diethyl aluminum

Bromide, dimethylaluminum fluoride, diethylaluminum fluoride, methylaluminum dichloride, ethylaluminum dichloride, methylaluminum dibromide, ethylaluminum dibromide, methylaluminum difluoride, ethylaluminum difluoride, methylaluminum sesquichloride , ethylaluminum sesquichloride (EASC), isobutylaluminum sesquichloride, methylmagnesium chloride, methylmagnesium bromide, ethylmagnesium chloride, ethylmagnesium bromide, n-butylmagnesium chloride, n-butylmagnesium bromide, phenylmagnesium chloride, phenyl Magnesium bromide, benzylmagnesium chloride, trimethyltin chloride, trimethyltin bromide, triethyltin chloride, triethyltin bromide, di-t-butyltin dichloride, di-t-butyltin dibromide, di-n-butyltin di Chloride, di-n-butyltin dibromide, tri-n-butyltin chloride, tri-n-butyltin bromide, methylmagnesium iodide, dimethylaluminum iodide, diethylaluminum iodide, di-n- Butyl aluminum iodide, diisobutyl aluminum iodide, di-n-octyl aluminum iodide, methyl aluminum diiodide, ethyl aluminum diiodide, n-butyl aluminum diiodide, isobutyl aluminum diiodide , methylaluminum sesquiiodide, ethylaluminum sesquiiodide, isobutylaluminum sesquiiodide, ethylmagnesium iodide, n-butylmagnesium iodide, isobutylmagnesium iodide, phenylmagnesium iodide, Benzylmagnesium iodide, trimethyltin iodide, triethyltin iodide, tri-n-butyltin iodide, di-n-butyltin diiodide or di-t-butyltin diiodide can be heard

In addition, the catalyst composition according to an embodiment of the present invention contains the halide in an amount of 1 to 20 moles, more specifically 1 to 5 moles, and more specifically 2 to 3 moles, based on 1 mole of the neodymium compound. may include If the halide is included in a molar ratio of more than 20, it is not easy to remove the catalytic reaction, and there is a fear that an excessive amount of the halide may cause a side reaction.

In addition, the catalyst composition according to an embodiment of the present invention may include a non-coordinating anion-containing compound or a non-coordinating anion precursor compound instead of or together with the halide.

Specifically, in the compound containing the non-coordinating anion, the non-coordinating anion is a sterically bulky anion that does not form a coordination bond with the active center of the catalyst system due to steric hindrance, and is a tetraarylborate anion or tetraaryl fluoride. borate anion, and the like. In addition, the compound containing the non-coordinating anion may include a carbonium cation such as a triaryl carbonium cation together with the non-coordinating anion; It may include an ammonium cation such as an N,N-dialkyl anilinium cation, or a counter cation such as a phosphonium cation. More specifically, the compound containing the non-coordinating anion is triphenyl carbonium tetrakis (pentafluorophenyl) borate, N,N-dimethylanilinium tetrakis (pentafluorophenyl) borate, triphenyl carbonium tetra kiss[3,5-bis(trifluoromethyl)phenyl]borate, or N,N-dimethylanilinium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, or the like.

In addition, as the non-coordinating anion precursor, a compound capable of forming a non-coordinating anion under reaction conditions, such as a triaryl boron compound (BE3, where E is a pentafluorophenyl group or a 3,5-bis (trifluoromethyl) phenyl group, etc.) strong electron-withdrawing aryl group).

(c) conjugated diene-based monomers

In addition, the catalyst composition may further include a conjugated diene-based monomer, and a portion of the conjugated diene-based monomer used in the polymerization reaction is mixed with the catalyst composition for polymerization in advance to perform pre-polymerization or pre-polymerization. By using it in the form of a premix catalyst composition, it is possible not only to improve the catalyst composition activity, but also to stabilize the active polymer to be prepared.

In the present invention, the "preforming" means a catalyst composition including a neodymium compound, an alkylating agent and a halide, that is, diisobutylaluminum hydride (DIBAH) in a catalyst system. In order to reduce the possibility of generating active species in the catalyst composition, a small amount of a conjugated diene-based monomer such as 1,3-butadiene is added. there is. In addition, "premix (premix)" may mean a state in which each compound is uniformly mixed without polymerization in the catalyst composition system.

In this case, the conjugated diene-based monomer used in the preparation of the catalyst composition may be used in an amount within the total amount of the conjugated diene-based monomer used in the polymerization, for example, 1 per mole of the neodymium compound. It may be used in an amount of from 10 moles to 100 moles, specifically from 10 moles to 50 moles, or from 20 moles to 50 moles.

The catalyst composition according to an embodiment of the present invention includes at least one of the aforementioned neodymium compound and alkylating agent, halide and conjugated diene-based monomers in an organic solvent, specifically, a neodymium compound, an alkylating agent and a halide, and optionally a conjugated diene. It can be prepared by mixing the system monomers. In this case, the organic solvent may be a non-polar solvent that is not reactive with the components of the catalyst composition. Specifically, the non-polar solvent is n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, isopentane, isohexane, isopentane, isooctane, 2,2-dimethylbutane, cyclo linear, branched or cyclic aliphatic hydrocarbons having 5 to 20 carbon atoms, such as pentane, cyclohexane, methylcyclopentane or methylcyclohexane; a mixed solvent of aliphatic hydrocarbons having 5 to 20 carbon atoms, such as petroleum ether or petroleum spirits, or kerosene; Alternatively, it may be an aromatic hydrocarbon-based solvent such as benzene, toluene, ethylbenzene, and xylene, and any one or a mixture of two or more thereof may be used. More specifically, the non-polar solvent may be a linear, branched or cyclic aliphatic hydrocarbon having 5 to 20 carbon atoms or a mixed solvent of aliphatic hydrocarbons, and more specifically, n-hexane, cyclohexane, or a mixture thereof. can

In addition, the organic solvent may be appropriately selected according to the constituent components constituting the catalyst composition, in particular, the type of the alkylating agent.

Specifically, in the case of alkylaluminoxane such as methylaluminoxane (MAO) or ethylaluminoxane as an alkylating agent, since it is not easily dissolved in an aliphatic hydrocarbon-based solvent, an aromatic hydrocarbon-based solvent may be appropriately used.

In addition, when modified methylaluminoxane is used as the alkylating agent, an aliphatic hydrocarbon-based solvent may be appropriately used. In this case, since it is possible to implement a single solvent system together with an aliphatic hydrocarbon-based solvent such as hexane, which is mainly used as a polymerization solvent, it may be more advantageous for the polymerization reaction. In addition, the aliphatic hydrocarbon-based solvent may promote catalytic activity, and reactivity may be further improved by such catalytic activity.

Meanwhile, the organic solvent may be used in an amount of 20 moles to 20,000 moles, more specifically, 100 moles to 1,000 moles, based on 1 mole of the neodymium compound.

Meanwhile, the polymerization in step 1 may be performed as a continuous polymerization in a polymerization reactor including at least two reactors, or may be performed in a batch reactor.

In addition, the polymerization may be an elevated temperature polymerization, an isothermal polymerization, or a constant temperature polymerization (adiabatic polymerization).

Here, the constant-temperature polymerization refers to a polymerization method comprising a step of polymerization with heat of reaction by itself without optionally applying heat after the catalyst composition is added. It shows a method, and the isothermal polymerization refers to a polymerization method in which heat is applied to increase heat after the catalyst composition is added, or heat is taken away to maintain a constant temperature of a reactant.

In addition, the polymerization may be carried out using coordination anionic polymerization or may be carried out by radical polymerization, specifically bulk polymerization, solution polymerization, suspension polymerization or emulsion polymerization, and more specifically solution polymerization. .

The polymerization may be carried out in a temperature range of -20 °C to 200 °C, specifically 50 °C to 150 °C, more specifically 10 °C to 120 °C or 60 °C to 90 °C for 15 minutes to It may be performed for 3 hours. If the polymerization temperature exceeds 200 ℃, it is difficult to sufficiently control the polymerization reaction, there is a risk that the cis-1,4 bond content of the resulting conjugated diene-based polymer may be lowered, and if the temperature is less than -20 ℃, polymerization There is a possibility that the reaction rate and efficiency may be lowered.

In addition, the method for producing the modified conjugated diene-based polymer according to an embodiment of the present invention includes a reaction terminator for completing the polymerization reaction such as polyoxyethylene glycol phosphate after preparing the active polymer; Alternatively, the polymerization may be terminated by further using an additive such as an antioxidant such as 2,6-di-t-butylparacresol. In addition, additives for facilitating solution polymerization together with the reaction terminator, for example, an additive such as a chelating agent, a dispersing agent, a pH adjusting agent, an oxygen scavenger or an oxygen scavenger may be optionally further used.

Step 2 is a step of preparing a modified conjugated diene-based polymer including a functional group by modifying or coupling the active polymer, and may be performed by reacting the active polymer with a modifier represented by Chemical Formula 1.

In general, when the active polymer and the modifier are reacted, as described above, the polymer has an organometallic moiety at the end of the active polymer, so that a reaction between the end of the polymer and the modifier occurs. only can be manufactured.

However, in the manufacturing method according to an embodiment of the present invention, the reaction of the double bond in the polymer chain composed of the conjugated diene-based monomer-derived unit and the azo group in the modifier as shown in Scheme 1 below by using the modifier represented by Formula 1 is In this case, the functional group derived from the denaturant may be bound to the polymer side chain as well.

[Scheme 1]

In Scheme 1, 1 represents a polymer main chain composed of a unit derived from a conjugated diene-based monomer, 2 represents a modifier, and 3 represents a structure of a polymer to which a functional group derived from the modifier is bonded.

Accordingly, the modified conjugated diene-based polymer prepared by the above preparation method according to an embodiment of the present invention may include a modifier-derived functional group in the polymer side chain, and may include a modifier-derived functional group at at least one end.

The modifier may be used in an amount of 0.5 to 20 moles based on 1 mole of the neodymium compound in the catalyst composition. Specifically, the modifier may be used in an amount of 1 mol to 15 mol relative to 1 mol of the neodymium compound in the catalyst composition, and more specifically, 2 mol to 15 mol relative to 1 mol of the neodymium compound in the catalyst composition.

In addition, the denaturation reaction may be performed at 0° C. to 90° C. for 1 minute to 5 hours.

After completion of the above-described modification reaction, a solution of 2,6-di-t-butyl-p-cresol (BHT) in isopropanol or the like may be added to the polymerization reaction system to stop the polymerization reaction.

In the manufacturing method according to an embodiment of the present invention, after step 2, a modified conjugated diene-based polymer can be obtained through a solvent removal treatment such as steam stripping or vacuum drying treatment to lower the partial pressure of the solvent through supply of water vapor. . In addition, an unmodified active polymer may be included in the reaction product obtained as a result of the above-mentioned reaction together with the above-mentioned modified conjugated diene polymer.

Furthermore, the present invention provides a rubber composition comprising the conjugated diene-based polymer and a molded article prepared from the rubber composition.

The rubber composition according to an embodiment of the present invention contains the modified conjugated diene-based polymer in an amount of 0.1 wt% to 100 wt%, specifically 10 wt% to 100 wt%, more specifically 20 wt% to 90 wt% may include. If the content of the modified conjugated diene-based polymer is less than 0.1% by weight, as a result, the effect of improving the abrasion resistance and crack resistance of a molded article manufactured using the rubber composition, for example, a tire, etc. may be insignificant.

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

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

In addition, the rubber composition may include 0.1 parts by weight to 150 parts by weight of a filler based on 100 parts by weight of the modified conjugated diene-based polymer, and the filler may be silica-based, carbon black, or a combination thereof. Specifically, the filler may be carbon black.

The carbon black-based filler is not particularly limited, but, for example, may have a nitrogen adsorption specific surface area (N2SA, measured in accordance with JIS K 6217-2:2001) of 20 m ² /g to 250 m ² /g. In addition, the carbon black may have a dibutyl phthalate oil absorption (DBP) of 80 cc/100g to 200 cc/100g. When the nitrogen adsorption specific surface area of the carbon black exceeds 250 m ² /g, the processability of the rubber composition may decrease, and if it is less than 20 m ² /g, the reinforcing performance by the carbon black may be insignificant. In addition, when the DBP oil absorption amount of the carbon black exceeds 200 cc/100g, there is a fear that the processability of the rubber composition is reduced, and when it is less than 80 cc/100g, the reinforcing performance by the carbon black may be insignificant.

In addition, the silica is not particularly limited, but may be, for example, wet silica (hydrous silicic acid), dry silica (silicic anhydride), calcium silicate, aluminum silicate or colloidal silica. Specifically, the silica may be wet silica having the most remarkable effect of improving fracture properties and coexisting effects of wet grip properties. In addition, the silica has a nitrogen adsorption specific surface area (nitrogen surface area per gram, N ₂ SA) of 120 m ² /g to 180 m ² /g, and a cetyl trimethyl ammonium bromide (CTAB) adsorption specific surface area of 100 m ² /g to 200 m ² /g. If the nitrogen adsorption specific surface area of the silica is less than 120 m ² /g, there is a fear that the reinforcing performance by the silica may decrease, and if it exceeds 180 m ² /g, there is a fear that the processability of the rubber composition may decrease. In addition, if the CTAB adsorption specific surface area of the silica is less than 100 m ² /g, the reinforcing performance by the silica filler may decrease, and if it exceeds 200 m ² /g, the processability of the rubber composition may decrease.

On the other hand, when silica is used as the filler, a silane coupling agent may be used together to improve reinforcement and low heat generation. Specifically, the silane coupling agent is 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-dimethylthiocarbamoyltetrasulfur Feed, 3-triethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-trimethoxysilyl Propylbenzothiazolyltetrasulfide, 3-triethoxysilylpropylbenzolyltetrasulfide, 3-triethoxysilylpropylmethacrylate monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, bis (3-diethoxymethylsilylpropyl)tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide or dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide and the like, and any one or a mixture of two or more thereof may be used. More specifically, in consideration of the reinforcing improvement effect, the silane coupling agent may be bis(3-triethoxysilylpropyl)polysulfide or 3-trimethoxysilylpropylbenzothiazyltetrasulfide.

In addition, the rubber composition according to an embodiment according to the present invention may be crosslinkable with sulfur, and thus may further include a vulcanizing agent.

The vulcanizing agent may be specifically sulfur powder, and may be included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the rubber component. When included in the above content range, it is possible to secure the required elastic modulus and strength of the vulcanized rubber composition, and at the same time to obtain low fuel economy.

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

The vulcanization accelerator is not particularly limited, and specifically, M (2-mercaptobenzothiazole), DM (dibenzothiazyl disulfide), CZ (N-cyclohexyl-2-benzothiazyl sulfenamide), etc. A thiazole-based compound of , or a guanidine-based compound such as DPG (diphenylguanidine) may be used. The vulcanization accelerator may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the rubber component.

In addition, the process oil acts as a softener in the rubber composition. Specifically, it may be a paraffinic, naphthenic, or aromatic compound. More specifically, when considering tensile strength and abrasion resistance, aromatic process oil price, hysteresis loss And in consideration of low-temperature characteristics, a naphthenic or paraffin-based process oil may be used. The process oil may be included in an amount of 100 parts by weight or less based on 100 parts by weight of the rubber component.

In addition, the antioxidant is specifically N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, 6- and oxy-2,2,4-trityl-2-dihydroquinoline, or a high-temperature condensate of diphenylamine and acetone. The antioxidant may be used in an amount of 0.1 to 6 parts by weight based on 100 parts by weight of the rubber component.

The rubber composition according to an embodiment of the present invention can be obtained by kneading using a kneader such as a Banbury mixer, a roll, an internal mixer, etc. according to the above formulation, and also has low heat generation and wear resistance by a vulcanization process after molding processing. This excellent rubber composition can be obtained.

Accordingly, the rubber composition may be used for each member of the tire, such as a tire tread, under tread, sidewall, carcass coated rubber, belt coated rubber, bead filler, cheaper, or bead coated rubber, anti-vibration rubber, belt conveyor, hose, etc. It may be useful in the manufacture of various industrial rubber products of

A molded article manufactured using the rubber composition may include a tire or a tire tread.

Hereinafter, the present invention will be described in more detail by way of Examples and Experimental Examples. However, the following Examples and Experimental Examples are intended to illustrate the present invention, and the scope of the present invention is not limited thereto.

<Example>

Preparation Example 1

[Step 1] In an ice bath, 4 g of benzoyl chloride was put into a 100 mL round bottom flask, 30 mL of acetonitrile was added as a reaction solvent, and then 3 g of ethyl carbazate was slowly added dropwise to react. When the reaction was completed, the produced solid was quantitatively obtained through filtration.

[Step 2] 3 g of the solid obtained in Step 1 was put into a 100 mL round bottom flask, dichloromethane 20 mL, and pyridine 2.5 mL were added in this order to dissolve the solid in a solvent. Then, under an ice bath, 2 g of N-bromosuccinimide was slowly added dropwise to react. When the reaction is complete, the by-products After extraction with water, moisture remaining in the organic layer was removed with sodium sulfate and filtered. The solvent was removed using a rotary evaporator to obtain a red liquid, thereby obtaining a denaturant represented by Chemical Formula 1-1.

1H nuclear magnetic resonance spectroscopy spectrum was observed to confirm the denaturant of Formula 1-1.

¹ H NMR (500 MHz, DMSO-d ₆ ) 7.88(3H, m), 7.69(2H, t), 4.54 (2H, t), 1.40 (3H, t).

Preparation 2

[Step 1] In an ice bath, 20 g of 4-(dimethylamino)benzoic acid was added to a 500 mL round bottom flask, 150 mL of acetonitrile was added as a reaction solvent, and then thionyl chloirde (8.8 mL) was slowly added dropwise to react. When the reaction was completed, ethyl carbazate (12.6 g) was added. The resulting solid was quantitatively obtained through filtration.

[Step 2] 30 g of the solid obtained in Step 1 was put into a 500 mL round bottom flask, acetonitrile 150 mL, and pyridine (19.5 mL) were added in this order to dissolve the solid in a solvent. Thereafter, N-bromosuccinimide (21 g) was slowly added dropwise under an ice bath to react. When the reaction is complete, the by-products After extraction with water, moisture remaining in the organic layer was removed with sodium sulfate and filtered. The solvent was removed using a rotary evaporator to obtain a red liquid, thereby obtaining a denaturant represented by Chemical Formula 1-2.

1H nuclear magnetic resonance spectroscopy spectrum was observed to confirm the denaturant of Formula 1-2.

¹ H NMR (500 MHz, DMSO-d ₆ ) 7.66 (2H, d), 6.84 (2H, d), 4.52 (2H, t), 3.08 (6H, s), 1.38 (3H, t).

Preparation 3

[ step 1] Put 100g of hydrazine monohydrate in a 500mL round bottom flask under an ice bath and add 125mL of acetonitrile. 2-ethylhexyl chloroformate (98 mL) was slowly added dropwise. When the reaction proceeded, the solvent was removed, dissolved in diethyl ether, extracted with NaHCO ₃ aqueous solution, separated and purified. A pink solution was obtained quantitatively.

[Step 2] 5 g of 4-(dimethylamino)benzoic acid was added to a 100 mL round bottom flask under an ice bath, 30 mL of acetonitrile was added as a reaction solvent, and then thionyl chloride (2.2 mL) was slowly added dropwise to react. When the reaction was completed, 8.5 g of the product of step 1 was added to produce a white solid. 8.3 g of the resulting solid was obtained through filtration.

[Step 3] 8.3 g of the solid obtained in Step 2 was put into a 100 mL round bottom flask, acetonitrile 30 mL, and pyridine 5 mL were added in this order to dissolve the solid in a solvent. Then, under an ice bath, 8.8 g of N-bromosuccinimide was slowly added dropwise to react. When the reaction is complete, the by-products After extraction with water, moisture remaining in the organic layer was removed with sodium sulfate and filtered. The solvent was removed using a rotary evaporator to obtain a red liquid, thereby obtaining a denaturant represented by Chemical Formula 1-3.

1H nuclear magnetic resonance spectroscopy was observed to confirm the denaturant of Formula 1-3.

¹ H NMR (500 MHz, DMSO-d ₆ ) 7.7 (2H, d), 7.2(2H, d), 4.40 (2H, t), 2.97(6H, s), 1.74 (1H, m), 1.39-1.28 (16H, m), 0.88 (6H, m).

Example 1

After putting 900 g of 1,3-butadiene and 6,600 g of n-hexane in a 20L autoclave reactor, the temperature inside the reactor was raised to 70°C. After the catalyst composition was added thereto, polymerization was performed for 60 minutes. In this case, the catalyst composition is obtained by adding neodymium versatate (Nd (2-ethylhexanoate) ₃ ), Solvay Corporation) in an n-hexane solvent, and diisobutylaluminum hydride (DIBAH), diethylaluminum Chloride (DEAC) was sequentially added to a molar ratio of the neodymium versatate:DIBAH:DEAC=1:16:2.4, and then mixed to prepare.

After the addition of the denaturant of Formula 1-1 prepared in Preparation Example 1, the denaturation reaction was performed at 70° C. for 30 minutes (denaturant: Nd=1:1 molar ratio). Thereafter, the reaction was terminated by adding a hexane solution containing 1.0 g of a polymerization terminator and a solution in which the antioxidant WINGSTAY (Eliokem SAS, France) was dissolved in hexane at 30% by weight, and the resulting polymer was heated with steam in hot water. The solvent was removed by stirring and then roll-drying to remove the residual amount of solvent and water to prepare a modified butadiene polymer.

Example 2

In Example 1, a modified butadiene polymer was prepared in the same manner as in Example 1, except that the modifier of Formula 1-2 prepared in Preparation Example 2 was used instead of the modifier of Formula 1-1 prepared in Preparation Example 1 did

Example 3

In Example 1, a modified butadiene polymer was prepared in the same manner as in Example 1, except that the modifier of Formula 1-3 prepared in Preparation Example 3 was used instead of the modifier of Formula 1-1 prepared in Preparation Example 1. did

Comparative Example 1

As an unmodified butadiene polymer, CB25 (Lanxess) was used as a comparative example.

Comparative Example 2

After putting 900 g of 1,3-butadiene and 6,600 g of n-hexane in a 20L autoclave reactor, the temperature inside the reactor was raised to 70°C. After the catalyst composition was added thereto, polymerization was performed for 60 minutes. In this case, the catalyst composition is obtained by adding neodymium versatate (Nd (2-ethylhexanoate) ₃ ), Solvay Corporation) in an n-hexane solvent, and diisobutylaluminum hydride (DIBAH), diethylaluminum Chloride (DEAC) was sequentially added to a molar ratio of the neodymium versatate:DIBAH:DEAC=1:16:2.4, and then mixed to prepare. Thereafter, the reaction was terminated by adding a hexane solution containing 1.0 g of a polymerization terminator and a solution in which the antioxidant WINGSTAY (Eliokem SAS, France) was dissolved in hexane at 30% by weight, and the resulting heavy content was heated with steam. The solvent was removed by stirring in hot water, and then roll-drying to remove the remaining amount of solvent and water to prepare an unmodified butadiene polymer.

Comparative Example 3

In Example 1, a modified butadiene polymer was prepared in the same manner as in Example 1, except that diisopropyl azodicarboxylate was used instead of the modifier of Formula 1-1 prepared in Preparation Example 1. did

<Experimental example>

Using the polymers of Examples 1 to 3 and Comparative Examples 1 to 3, each physical property was measured in the following manner, and the results are shown in Table 1 below.

After preparing the rubber composition and the rubber specimen, Mooney viscosity, tensile stress, 300% modulus, abrasion resistance, and viscoelastic properties were measured as follows. The results are shown in Table 1 below.

1) Mooney viscosity and Mooney viscosity difference (ΔMV)

For each polymer, Mooney viscosity (ML1+4, @100°C) (MU) was measured using a large rotor with a Monsanto MV2000E at 100°C and a rotor speed of 2±0.02 rpm. At this time, the sample used at this time was left at room temperature (23±3℃) for more than 30 minutes, then 27±3g was collected, filled inside the die cavity, and the platen was operated to apply the torque while applying the Mooney viscosity (MV, mooney viscority). ) was measured.

Mooney viscosity (ML1+4, @100°C) (MU) of the formulation was measured using each of the vulcanized formulations prepared above. Specifically, the Mooney viscosity (MV) was measured at 100° C. with a Rotor Speed of 2±0.02 rpm using a large rotor with a Monsanto MV2000E. At this time, the sample used at this time was left at room temperature (23±3℃) for more than 30 minutes, then 27±3g was collected and filled inside the die cavity, and the Mooney viscosity (compound MW) of the compound was applied while the platen was operated to apply torque. , compound mooney viscority) was measured.

In addition, the Mooney viscosity of each polymer shown in Table 1 and the Mooney viscosity difference (ΔMV) of the formulation were calculated. In this case, the smaller the Mooney viscosity difference, the better the processability.

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

Each polymer was dissolved in tetrahydrofuran (THF) for 30 minutes under a condition of 40° C., and then loaded and flowed through gel permeation chromatography (GPC). In this case, as the column, two PLgel Olexis columns manufactured by Polymer Laboratories and one PLgel mixed-C column were used in combination. In addition, all of the newly replaced columns used a mixed bed type column, and polystyrene was used as a gel permeation chromatography standard material (GPC standard material).

A rubber composition and a rubber specimen were prepared as follows.

3) Preparation of rubber composition and rubber specimen

To 100 parts by weight of each polymer of Examples 1 to 3 and Comparative Examples 1 to 3, 70 parts by weight of carbon black, 22.5 parts by weight of process oil, 2 parts by weight of antioxidant (TMDQ), 3 parts by weight of zinc oxide (ZnO) Each rubber composition was prepared by mixing parts and 2 parts by weight of stearic acid. Then, 2 parts by weight of sulfur, 2 parts by weight of vulcanization accelerator (CZ) and 0.5 parts by weight of vulcanization accelerator (DPG) were added to each rubber composition, and gently mixed at 50 rpm for 1.5 minutes at 50 ° C. Using a roll at 50 ° C. Thus, a vulcanized formulation in the form of a sheet was obtained. The obtained vulcanized mixture was vulcanized at 160° C. for 25 minutes to prepare a rubber specimen.

4) tensile stress and 300% modulus

After vulcanizing each rubber composition at 150° C. for t90 minutes, the tensile stress and modulus (M-300%) at 300% elongation of the vulcanized product were measured according to ASTM D412.

5) Wear resistance (DIN index)

DIN abrasion test was performed on each rubber specimen according to ASTM D5963, and was expressed as DIN wt loss index (loss volume index: ARIA (Abrasion resistance index, Method A)).

6) Viscoelastic properties

The most important property of Tan δ for low fuel efficiency was measured using DMTS 500N from Gabo, Germany, at a frequency of 10 Hz, Prestrain 3%, and Dynamic Strain 3% at -60°C to 60°C (Tan δ). At this time, the Tanδ value at 0°C indicates low road resistance, and the Tanδ value at 60°C indicates the rolling resistance characteristic (fuel efficiency).

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 MV 50 53 49 48 46 51 Compound MV 100 104 102 95 93 102 △ MV 50 51 53 49 47 51 Mn (x10 ⁵ g/mol) 2.50 2.42 2.71 2.64 2.13 2.54 Mw (x10 ⁵ g/mol) 6.95 6.55 6.84 6.18 4.92 7.12 MWD (Mw/Mn) 2.78 2.70 2.52 2.34 2.31 2.80 M-300% index 110 110 112 100 108 108 Tensile stress index 108 108 109 100 106 105 Din index 104 105 105 100 99 101 Tanδ at 0℃ index 103 105 107 100 100 99 Tanδ at 60℃ index 108 121 125 100 103 105

In Table 1, the resultant values of tensile properties, abrasion resistance, and Tanδ values at 0° C. of Examples 1 to 3 and Comparative Examples 2 to 3 are calculated by the following Equation 2 based on the measurement value of Comparative Example 1 and indexed (index), and the Tanδ value at 60° C. was calculated and indexed by Equation 3 below.

[Equation 2]

Index=(measured value/reference value)×100

[Equation 3]

Index=(reference value/measurement value)×100

In Table 1, the modified butadiene polymers of Examples 1 to 3 had an increased weight average molecular weight compared to the unmodified butadiene polymer of Comparative Example 2, and through this, the modified butadiene polymers of Examples 1 to 3 were prepared by Formula 1- 1, it can be confirmed that the denaturation by Chemical Formula 1-2 or Chemical Formula 1-3.

Examples 1 to 3 exhibited improved effects in tensile properties, abrasion resistance and viscoelastic properties while exhibiting excellent processability at the same level as Comparative Examples 1 to 3.

Specifically, Examples 2 to 3 showed improved tensile properties, abrasion resistance and wet road resistance compared to Comparative Examples 2 and 3, and the rolling resistance was respectively about 17% to about 21%, or about 15% to 19% showed a remarkably improved effect. Here, Comparative Example 2 is an unmodified polymer prepared in the same manner except that it is not modified with the azo group-containing compound of the present invention, and Comparative Example 3 contains an azo group but modified with a material different from the compound presented in the present invention It is a modified polymer produced by

Example 1 did not have an amine group that could act with the filler, so the rotation resistance was somewhat lower than that of Examples 2 to 3, but improved effects compared to Comparative Examples 1 to 3 in terms of tensile properties, abrasion resistance and viscoelastic properties.

Through the above results, it can be confirmed that the azo group-containing compound represented by Formula 1 of the present invention is applied as a polymer modifier to have an excellent effect of improving the physical properties of the polymer, and furthermore, the modified conjugated diene-based polymer according to the present invention has the azo group By including a functional group derived from the containing compound, particularly a filler affinity functional group such as carbon black, it can be confirmed that the filler affinity is excellent, the compounding properties are improved, and the rotation resistance is greatly improved.

Claims (11)

A modified conjugated diene-based polymer comprising a functional group derived from a modifier represented by the following formula (1):
[Formula 1]

In Formula 1,
R ₁ , R ₂ , and R ₃ are each independently an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms,
a is 0 to 2.
The method of claim 1,
In Formula 1, R ₁ , R ₂ , and R ₃ are each independently a linear or branched alkyl group having 1 to 10 carbon atoms, a modified conjugated diene-based polymer.
The method of claim 1,
In Formula 1, R ₁ , R ₂ , and R ₃ are each independently a methyl group, an ethyl group, or a 2-ethylhelyl group, a modified conjugated diene-based polymer.
The method of claim 1,
The modifier represented by Formula 1 is one selected from the group consisting of compounds represented by Formula 1-1 to Formula 1-3, a modified conjugated diene-based polymer:
[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

The method of claim 1,
The polymer is a modified conjugated diene-based polymer comprising a functional group derived from the modifier represented by Formula 1 in the side chain.
The method of claim 1,
The polymer is a modified conjugated diene-based polymer comprising a functional group derived from the modifier represented by Formula 1 at at least one terminal.
1) preparing an active polymer by polymerizing a conjugated diene-based monomer in the presence of a catalyst composition including a neodymium compound in a hydrocarbon solvent; and
2) The method for producing the modified conjugated diene-based polymer according to claim 1, comprising the step of reacting the active polymer with a modifier represented by Formula 1:
[Formula 1]

In Formula 1,
R ₁ , R ₂ , and R ₃ are each independently an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms,
a is 0 to 2.
8. The method of claim 7,
The method for producing a modified conjugated diene-based polymer wherein the catalyst composition is used in an amount such that the neodymium compound is 0.1 mmol to 0.5 mmol based on 100 g of the conjugated diene-based monomer.
8. The method of claim 7,
The neodymium compound is a method for producing a modified conjugated diene-based polymer that is a compound represented by the following formula 3:
[Formula 3]

In Formula 3,
Ra to Rc are each independently hydrogen or an alkyl group having 1 to 12 carbon atoms, provided that Ra to Rc are not all hydrogen at the same time.
8. The method of claim 7,
The method for producing a modified conjugated diene-based polymer wherein the modifier is used in a ratio of 0.5 to 20 moles based on 1 mole of the neodymium compound.
A rubber composition comprising the modified conjugated diene-based polymer according to claim 1 .