KR20220034664A - Method for preparing modified conjugated diene polymer - Google Patents

Abstract

The present invention relates to a method for producing a modified conjugated diene-based polymer, and specifically, to a method for producing a modified conjugated diene-based polymer having excellent processability and filler dispersibility and excellent quality stability by suppressing changes over time. The method for producing a modified conjugated diene-based polymer includes: a step of polymerizing a conjugated diene-based monomer to prepare an active polymer; a step of reacting the active polymer with an amine-based modifier to prepare a modified polymer; and a step of reacting the modified polymer with a mixture of a phenol-based antioxidant and a diarylamine-based antioxidant.

Description

Method for producing a modified conjugated diene-based polymer {METHOD FOR PREPARING MODIFIED CONJUGATED DIENE POLYMER}

The present invention relates to a method for producing a modified conjugated diene-based polymer, and more particularly, to a method for producing a modified conjugated diene-based polymer having excellent processability and filler dispersibility and excellent quality stability by suppressing changes over time.

Recently, as interest in energy saving and environmental issues increases, fuel efficiency reduction of automobiles is required. As one of the methods for realizing this, a method for lowering the exothermicity 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. There was a problem in that the physical properties of the rubber composition, including abrasion resistance, crack resistance, or processability, etc. were generally lowered.

In order to solve this problem, as a method for increasing the dispersibility of inorganic fillers such as silica or carbon black in the rubber composition, the polymerization active site of the conjugated diene-based polymer obtained by anionic polymerization using organolithium can interact with the inorganic filler. A method of denaturation with a functional group has been developed. Specifically, a method of modifying the polymerization active terminal of a conjugated diene-based polymer with a tin-based compound, introducing an amino group, or modifying with an alkoxysilane derivative has been proposed.

However, when manufacturing a rubber composition using the conjugated diene-based polymer modified by the above method, low heat generation can be secured, but the effect of improving physical properties of the rubber composition, such as abrasion resistance and processability, was not sufficient.

As another method, in a living polymer obtained by coordination polymerization using a catalyst containing a lanthanum-based rare-earth element compound, a method has been developed in which the living active terminal is modified with a specific coupling agent or modifier. However, in a catalyst containing a conventionally known lanthanum-based rare earth element compound, the resulting living end activity is weak and the terminal modification rate is low, so that the effect of improving the physical properties of the rubber composition is insignificant.

U.S. Patent No. 5,557,784

It is an object of the present invention to provide a method for producing a modified conjugated diene-based polymer having excellent compounding properties and improved processability by imparting affinity to carbon black and silica, and at the same time having low change over time and improved stability.

Another object of the present invention is to provide a modified conjugated diene-based polymer prepared by the above manufacturing method and a rubber composition comprising the same.

In order to solve the above problems, the present invention comprises the steps of (S1) 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; (S2) preparing a modified polymer by reacting the active polymer with an amine-based modifier; and (S3) reacting the modified polymer with a mixture of a phenol-based antioxidant and a diarylamine-based antioxidant.

The modified conjugated diene-based polymer prepared by the manufacturing method according to the present invention exhibits excellent affinity for the functional group derived from the amine-based modifier to the filler, thereby improving dispersibility in the rubber composition and excellent processability. , can exhibit excellent physical properties such as abrasion resistance.

In addition, since the change over time of the modified conjugated diene-based polymer finally manufactured through the manufacturing method of the present invention is suppressed, it is possible to prevent changes in physical properties during long-term storage, thereby improving storage stability.

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 description and claims of the present invention should not be construed as being limited to their ordinary or dictionary meanings, and the inventor appropriately defines the concept of the term in order to best describe his invention. Based on the principle that it can be done, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

The method for producing a modified conjugated diene-based polymer of the present invention comprises the steps of: (S1) 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; (S2) preparing a modified polymer by reacting the active polymer with an amine-based modifier; and (S3) reacting the modified polymer with a mixture of a phenol-based antioxidant and a diarylamine-based antioxidant.

Step (S1)

The step (S1) is a step 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, wherein the active polymer is a polymer of the conjugated diene-based monomer and an organometallic site It may indicate that it contains

The organometallic moiety may be an activated organometallic moiety at the end of a polymer (an activated organometallic moiety at the end of a molecular chain), an activated organometallic moiety in a main chain, or an activated organometallic moiety in a side chain (side chain), Among them, when an activated organometallic moiety of the copolymer is obtained by anionic polymerization or coordination anionic polymerization, the organometallic moiety may represent an activated organometallic moiety at the end.

The polymerization may be carried out by radical polymerization, and may be carried out by various polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization or emulsion polymerization, and may be carried out by a batch method, a continuous method, or a semi-continuous method. it might be As a specific example, the polymerization for preparing the active polymer may be carried out by reacting by adding a conjugated diene-based monomer to the catalyst composition in an organic solvent.

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

The polymerization may be carried out in a temperature range of -20 to 200 °C, specifically, at a temperature of 10 °C or higher, 30 °C or higher, 50 °C or higher, 180 °C or lower, 150 °C or lower, 100 °C or lower, 80 °C or lower. It may be performed in a range. If the polymerization temperature exceeds 200°C, it is difficult to sufficiently control the polymerization reaction and 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°C, the polymerization reaction There is a fear that the speed and efficiency may be lowered.

In addition, the polymerization may be carried out for 5 minutes or more, 10 minutes or more, 2 hours or less, and 1 hour or less within the above temperature range until 100% conversion of the conjugated diene-based polymer is reached, but is not limited thereto.

As the conjugated diene-based monomer, it can be used without any particular limitation as long as it is generally used in the preparation of a conjugated diene-based polymer. The conjugated diene-based monomer is specifically 1,3-butadiene, isoprene, 1,3-pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3- butadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, or 2,4-hexadiene, and any one of these or A mixture of two or more may be used. More specifically, the conjugated diene-based monomer may be 1,3-butadiene.

In addition, other monomers copolymerizable with the conjugated diene-based monomer may be further used in consideration of the physical properties of the active polymer finally produced during the polymerization reaction, specifically styrene, p-methyl styrene, α-methyl styrene, 1 -It may be an aromatic vinyl monomer such as vinylnaphthalene, 3-vinyltoluene, ethylvinylbenzene, divinylbenzene, 4-cyclohexylstyrene, 2,4,6-trimethylstyrene, etc., and any one or a mixture of two or more thereof may be used can The other monomers may be used in an amount of 20% by weight or less based on the total weight of the monomers used in the polymerization reaction.

In this case, the amount of the conjugated diene-based monomer used for preparing the conjugated diene-based polymer is not entirely dissolved in a non-polar solvent, but a portion of the total amount used is dissolved in the polymerization solvent and polymerized, depending on the polymerization conversion rate One or more times, specifically, two or more times, more specifically, may be divided into 2 to 4 times.

The hydrocarbon solvent may be a non-polar solvent. Specifically, the hydrocarbon solvent is an aliphatic hydrocarbon solvent such as pentane, hexane, isopentane, heptane, octane, isooctane; cycloaliphatic hydrocarbon solvents such as cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane and the like; Alternatively, one or more selected from the group consisting of aromatic hydrocarbon solvents such as benzene, toluene, ethylbenzene, and xylene may be used. As a specific example, the hydrocarbon solvent may be an aliphatic hydrocarbon solvent such as hexane. When the polymerization solvent is used, the concentration of the monomer is not particularly limited, but may be 3 wt% to 80 wt%, more specifically 10 wt% to 30 wt%.

The catalyst composition may be used in an amount such that the neodymium compound is 0.03 to 0.15 mmol based on 100 g of the total of the conjugated diene-based monomers, specifically, 0.05 to 0.15 mmol of the neodymium compound based on 100 g of the total of the conjugated diene-based monomers It may be used in an amount that makes it possible.

After the neodymium compound is activated by a first alkylating agent and a second alkylating agent to be described later, a catalytically active species for polymerization of the conjugated diene-based monomer is formed.

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.

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

[Formula 3]

In Formula 3,

R _a to R _c are each independently hydrogen or an alkyl group having 1 to 12 carbon atoms, provided that R _a to R _c are not all hydrogen at the same time.

In addition, 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, R _a has 4 to 12, and R _b and R _c are each independently hydrogen or an alkyl group having 2 to 8 carbon atoms, provided that R _b and R _c are not hydrogen at the same time.

As a more specific example, in Formula 3, R _a is an alkyl group having 6 to 8 carbon atoms, R _b and R _c may each independently be hydrogen or an alkyl group having 2 to 6 carbon atoms, wherein R _b and R _c are At the same time, it may not be hydrogen.

More specifically, in Formula 3, R _a may be an alkyl group having 6 to 8 carbon atoms, and R _b and R _c may each independently be an alkyl group having 2 to 6 carbon atoms.

As such, the neodymium compound represented by Chemical 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 between the compounds It is possible to block the agglomeration phenomenon, and thus, there is an effect of suppressing oligomerization. In addition, such a neodymium 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.

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-dipropyl nonanoate) 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, the solubility of the neodymium compound may be about 4 g or more per 6 g of the non-polar solvent at room temperature (23 ± 5 °C). The solubility of the neodymium compound refers to the degree to which it is clearly dissolved without turbidity, and by exhibiting such high solubility, excellent catalytic activity can be exhibited.

In addition, the neodymium compound 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.

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

(a) first alkylating agent

The first alkylating agent may be aluminoxane, and the aluminoxane may be prepared by reacting a trihydrocarbyl aluminum-based compound with water. Specifically, the aluminoxane may be a straight-chain aluminoxane of the following Chemical Formula 4a or a cyclic aluminoxane of the 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 from 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 each independently be 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 one in which about 50 mol% to 90 mol% of the methyl group of methylaluminoxane is substituted 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, according to an embodiment of the present invention, it is possible to form a narrow molecular weight distribution of the modified conjugated diene-based polymer to be prepared, and thus, preferably in terms of improving the physical properties of the polymer, the first alkylating agent is methylaluminoxane or modified methyl It may be aluminoxane.

(b) a second alkylating agent

The second alkylating agent according to an embodiment of the present invention may be dihydrocarbylaluminum hydride or hydrocarbylaluminum dihydride, and specifically, the second alkylating agent is 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, phenylisobutylaluminum hydride, phenyl-n -Octylaluminum hydride, p-tolylethylaluminum hydride, p-tolyl-n-propylaluminum hydride, p-tolylisopropylaluminum hydride, p-tolyl-n-butylaluminum hydride, p-tolylisobutyl Aluminum hydride, p-tolyl-n-octylaluminum hydride, benzylethylaluminum hydride, benzyl-n-propylaluminum hydride, benzylisopropylaluminum hydride, benzyl-n-butylaluminum hydride, benzylisobutylaluminum dihydrocarbylaluminum hydride such as hydride or benzyl-n-octylaluminum hydride; hydrocarbylaluminum dihydrides such as ethylaluminum dihydride, n-propylaluminum dihydride, isopropylaluminum dihydride, n-butylaluminum dihydride, isobutylaluminum dihydride, and n-octylaluminum dihydride; or a combination thereof.

In the catalyst composition, the alkylating agent is an organometallic compound capable of transferring a hydrocarbyl group to another metal, and may serve as a co-catalyst.

In addition, if necessary, the catalyst composition of the present invention may further include a conventional alkylating agent used as an alkylating agent in the preparation of a conjugated diene-based polymer in addition to the above first and second alkylating agents, such alkylating agents include trimethylaluminum, trimethylaluminum Ethyl aluminum, tri-n-propyl aluminum, triisopropyl aluminum, tri-n-butyl aluminum, triisobutyl aluminum, tri-t-butyl aluminum, tripentyl aluminum, trihexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum alkyl aluminum, such as; and alkylmagnesium compounds such as diethylmagnesium, di-n-propylmagnesium, diisopropylmagnesium, dibutylmagnesium, dihexylmagnesium, diphenylmagnesium, or dibenzylmagnesium. -Alkyl lithium compounds, such as butyllithium, etc. are mentioned.

(c) halides

The type of the halide is not particularly limited, but may be used without any particular limitation as long as it is generally used as a halide in the production of a diene-based polymer.

Specifically, the halide may include a halogen simple substance, an interhalogen compound, a hydrogen halide, an organic 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.

More specifically, the halogen alone may include fluorine, chlorine, bromine or iodine.

In addition, specific 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 be specifically hydrogen fluoride, hydrogen chloride, hydrogen bromide or hydrogen iodide.

In addition, the organic halide is specifically t-butyl chloride (t-BuCl), t-butyl bromide, allyl chloride, allyl bromide, benzyl chloride, benzyl bromide, chloro-di-phenylmethane, bromo-di-phenylmethane , triphenylmethyl chloride, triphenylmethyl bromide, benzylidene chloride, benzylidene bromide, methyltrichlorosilane, phenyltrichlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, trimethylchlorosilane (TMSCl), benzoyl chloride, benzoyl bromide , propionyl chloride, propionyl bromide, methyl chloroformate, methyl bromoformate, iodomethane, diiodomethane, triiodomethane (also called iodoform), tetraiodomethane, 1-io Dopropane, 2-iodopropane, 1,3-diiodopropane, t-butyl iodide, 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, the non-metal halide is specifically phosphorus trichloride, phosphorus tribromide, phosphorus pentachloride, phosphorus oxychloride, phosphorus oxybromide, boron trifluoride, boron trichloride, boron tribromide, silicon tetrafluoride, silicon tetrachloride (SiCl ₄ ), Silicon bromide, 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 etc. are mentioned.

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

In addition, the organometallic halide is specifically dimethylaluminum chloride, diethylaluminum chloride, dimethylaluminum bromide, diethylaluminum bromide, dimethylaluminum fluoride, diethylaluminum fluoride, methylaluminum dichloride, ethylaluminum dichloride, methyl Aluminum 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, phenylmagnesium bromide, benzylmagnesium chloride, trimethyltin chloride, trimethyltin bromide, triethyltin chloride, triethyltin bromide , di-t-butyltin dichloride, di-t-butyltin dibromide, di-n-butyltin dichloride, di-n-butyltin dibromide, tri-n-butyltin chloride, tri-n-butyl Tin bromide, methylmagnesium iodide, dimethylaluminum iodide, diethylaluminum iodide, di-n-butylaluminum iodide, diisobutylaluminum iodide, di-n-octylaluminum iodide, Methylaluminum diiodide, ethylaluminum diiodide, n-butylaluminum diiodide, isobutylaluminum diiodide, methylaluminum sesquiiodide, ethylaluminum sesquiiodide, isobutylaluminum sesquiiodide, ethyl Magnesium iodide, n-butylmagnesium iodide, isobutylmagnesium iodide, phenylmagnesium iodide, benzylmagnesium iodide, trimethyltin iodide, triethyltin iodide, tri-n-butyl and tin iodide, di-n-butyltin diiodide, or di-t-butyltin diiodide.

In addition, the catalyst composition of the present invention may contain 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 is a carbon cation such as a triaryl carbonium cation together with the above non-coordinating anion, an ammonium cation such as a N,N-dialkyl anilinium cation, or a relative of a phosphonium cation. It may contain a cation. More specifically, the compound containing the non-coordinating anion is triphenylcarbonium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, triphenylcarbonium tetra kiss[3,5-bis(trifluoromethyl)phenyl]borate, or N,N-dimethylanilinium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, or the like.

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

(d) 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" refers to 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, in the method for producing a modified conjugated diene-based polymer of the present invention, after preparing the active polymer, a reaction terminator or 2,6-di-t-butylparacresol for completing the polymerization reaction such as polyoxyethylene glycol phosphate, etc. It may include the step of terminating the polymerization by further using an additive such as an antioxidant such as the like. 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 (S2)

The step (S2) is a step of reacting the active polymer prepared in step (S1) with an amine-based modifier to prepare a modified polymer, wherein the modified polymer has an amine-based modifier-derived functional group at at least one end of the conjugated diene-based polymer chain It may include the polymer incorporated therein, and may include the active polymer in a state that remains unmodified.

The amine-based modifier can be applied to the present invention without limitation as long as it is a modifier containing an amine functional group, and specifically, a functional end capable of reacting with an amine group protected with trialkylsilyl and an active polymer. group), for example, may be a compound containing an ester group, a halogen group, a carbonyl group, and the like. The trialkylsilyl-protected amine group means that one or both of the hydrogen atoms of the amine group are substituted with a trialkylsilyl group that is a protecting group. When both hydrogen atoms of the amine group are substituted with a trialkylsilyl group, it is also possible that two alkyl groups each bonded to a different trialkylsilyl group are connected to each other to form a ring together with the N of the amine group. At least one amine group protected by the trialkylsilyl may be included in the amine-based modifier, and in this case, the amine group may be a primary amine group, a secondary amine group, or a tertiary amine group.

In the present invention, the amine-based modifier may be a compound represented by any one of the following Chemical Formulas A to C, but is not limited thereto.

[Formula A]

In the above formula (A),

R ₁ to R ₃ are each independently a halogen group, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, and one or more substituents selected from the group consisting of -R _a COOR _b A substituted trivalent hydrocarbon group or an unsubstituted divalent hydrocarbon group having 1 to 10 carbon atoms, wherein R _a is a single bond, an alkylene group having 1 to 20 carbon atoms, or a cycloalkylene group having 3 to 20 carbon atoms, R _b is an alkyl group having 1 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms,

However, R ₁ to R ₃ are not all at the same time a trivalent hydrocarbon group or a divalent hydrocarbon group,

R ₄ is a single bond, an alkylene group having 1 to 20 carbon atoms, or a cycloalkylene group having 3 to 20 carbon atoms,

R ₅ to R ₇ are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms.

[Formula B]

In the above formula (B),

R ₈ to R ₁₀ are each independently —SiR _c R _d R _e ,

R ₁₁ is a C 1 to C 20 divalent hydrocarbon group unsubstituted or substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms and an aryl group having 6 to 30 carbon atoms; ,

R ₁₂ is a divalent hydrocarbon group having 2 to 20 carbon atoms,

R ₁₃ is -COOR _f ,

In the above, R _c , R _d and R _e are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms,

R _f is an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 20 carbon atoms.

[Formula C]

In the above formula (C),

R ₁₄ is a trivalent hydrocarbon group substituted with one or more substituents selected from the group consisting of a halogen group, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms, or an unsubstituted C 1 to 10 is a divalent hydrocarbon group,

R ₁₅ is an alkylene group having 1 to 20 carbon atoms or a cycloalkylene group having 3 to 20 carbon atoms,

R ₁₆ is a silyl group unsubstituted or substituted with an alkyl group having 1 to 20 carbon atoms, a halogen group, or -COR _g , where R _g is an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, 2 to carbon atoms It is one selected from the group consisting of a heteroaryl group of 30, a heterocycloalkyl group having 2 to 10 carbon atoms, a heteroamine group having 2 to 10 carbon atoms, and a disilylaminoalkyl group having 3 to 10 carbon atoms,

R ₁₇ to R ₂₀ are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms.

The amine-based modifier used in the present invention can easily modify the conjugated diene-based polymer at a high modification rate by including a reactive functional group, a filler affinity functional group, and a solvent affinity functional group for the conjugated diene-based polymer, and a rubber composition comprising the same; It is possible to improve abrasion resistance, low fuel consumption characteristics, and workability of molded articles such as tires manufactured therefrom. Specifically, the amine-based modifier may include a reactive functional group, an amine group, and an alkyl chain with respect to the polymer in the molecule as described above, and the reactive functional group exhibits high reactivity toward the active site of the conjugated diene-based polymer. As a result, the conjugated diene-based polymer can be modified at a high rate of modification, and as a result, the functional group substituted with the modifier can be introduced into the conjugated diene-based polymer with a high yield.

In addition, the amine group reacts with the end of the conjugated diene-based polymer to be converted into a primary or secondary amino group, thereby further improving affinity with a filler, particularly carbon black. In addition, the alkyl chain may increase the affinity for the polymerization solvent to increase the solubility of the modifier, thereby improving the rate of modification of the conjugated diene-based polymer.

As a result, by using the modifier in the present invention, the physical properties of the rubber composition including the modified conjugated diene-based polymer and the finally obtained molded article, in particular, the tensile strength of the tire, abrasion resistance, rolling resistance, low running resistance, etc. can be improved.

However, when the modifier as described above is used in the present invention, an amine group derived from an amine modifier is included in the modified conjugated diene-based polymer, and the amine group acts as a functional group and continues to couple with the unmodified conjugated diene-based polymer even after the modification reaction is completed. Rings may occur, which causes changes in physical properties such as an increase in Mooney viscosity and molecular weight of the modified conjugated diene-based polymer and a decrease in linearity. As such, the modified conjugated diene-based polymer prepared using an amine-based modifier shows a large change in physical properties over time, so it may cause Mooney viscosity spec-out in the storage and distribution stage of the product and adversely affect physical properties and processability. there will be

Accordingly, in the present invention, as described later, the change over time of the modified conjugated diene-based polymer was suppressed by using a phenol-based antioxidant and a diarylamine-based antioxidant in combination. In addition, the modified conjugated diene-based polymer prepared as described above exhibits excellent compounding properties such as tensile properties and viscoelastic properties when applied to a rubber composition.

Specifically, in Formula A, R ₁ to R ₃ are each independently a halogen group, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, and -R _a COOR _b A trivalent hydrocarbon group substituted with one or more substituents selected from the group or an unsubstituted divalent hydrocarbon group having 1 to 10 carbon atoms, wherein R _a is a single bond, an alkylene group having 1 to 20 carbon atoms, or 3 to 20 carbon atoms is a cycloalkylene group of, R _b is an alkyl group having 1 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms, with the proviso that R ₁ to R ₃ are not both a trivalent hydrocarbon group or a divalent hydrocarbon group at the same time, and R ₄ and R _a may be a single bond, R _b may be a linear or branched alkyl group having 1 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms, R ₅ to R ₇ are each independently hydrogen or a carbon number 1 to 20 linear or branched alkyl groups.

As another example, in Formula A, R ₁ and R ₃ may each independently be an unsubstituted divalent hydrocarbon group having 1 to 10 carbon atoms, and R ₂ may be a trivalent hydrocarbon group substituted with -R _a COOR _b , , R ₄ and R _a may be a single bond, R _b may be a linear or branched alkyl group having 1 to 20 carbon atoms, and R ₅ to R ₇ are each independently a linear or branched alkyl group having 1 to 20 carbon atoms can

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

[Formula A-1]

[Formula A-2]

[Formula A-3]

In addition, in Formula B, R ₈ to R ₁₀ are each independently —SiR _c R _d R _e , wherein R _c , R _d and R _e are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms. and, specifically, R _c , R _d and R _e may each independently be an alkyl group having 1 to 10 carbon atoms.

R ₁₁ may be a divalent hydrocarbon group having 1 to 20 carbon atoms or a divalent hydrocarbon group having 1 to 20 carbon atoms substituted with a substituent.

When R ₁₁ is a divalent hydrocarbon group having 1 to 20 carbon atoms, R ₁₁ is an alkylene group having 1 to 10 carbon atoms, such as a methylene group, an ethylene group, or a propylene group; an arylene group having 6 to 20 carbon atoms, such as a phenylene group; Or a combination group thereof may be an arylalkylene group having 7 to 20 carbon atoms. More specifically, R ₁₁ may be an alkylene group having 1 to 10 carbon atoms. In addition, when R ₁₁ is a divalent hydrocarbon group having 1 to 20 carbon atoms substituted with a substituent, R ₁₁ is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms. It may be an alkylene group having 1 to 10 carbon atoms substituted with one or more selected substituents.

In addition, in Formula B, R ₁₂ may be a divalent hydrocarbon group having 2 to 20 carbon atoms, and specifically, an alkylene group having 2 to 10 carbon atoms.

In addition, in Formula B, R ₁₃ may be -COOR _f , and R _f may be an alkyl group having 1 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms. Specifically, R _f may be selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an arylalkyl group having 7 to 12 carbon atoms.

Specifically, the modifier in Formula B, R ₈ to R ₁₀ are each independently -SiR _c R _d R _e , R ₁₁ and R ₁₂ are each independently an alkylene group having 2 to 10 carbon atoms, and R ₁₃ is - COOR _f , wherein R _c , R _d and R _e are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms, and R ₁₀ is an alkyl group having 1 to 10 carbon atoms that is unsubstituted or substituted with an alkyl group having 1 to 10 carbon atoms it could be

More specifically, the modifier represented by Formula B may be a compound represented by Formulas B-1 to B-3.

[Formula B-1]

[Formula B-2]

[Formula B-3]

In Formulas B-1 to B-3, TMS represents a trimethylsilyl group.

In Formula (C), R ₁₄ is a trivalent hydrocarbon group substituted with one or more substituents selected from the group consisting of a halogen group, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms. It may be a cyclic divalent hydrocarbon group having 1 to 10 carbon atoms, R ₁₅ may be an alkylene group having 1 to 20 carbon atoms, or a cycloalkylene group having 3 to 20 carbon atoms, and R ₁₆ is a substituted or It may be an unsubstituted silyl group, a halogen group, or -COR _g , where R _g is an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, 2 to 10 carbon atoms. may be one selected from the group consisting of a heterocycloalkyl group, a heteroamine group having 2 to 10 carbon atoms, and a disilylaminoalkyl group having 3 to 10 carbon atoms, wherein R ₁₇ to R ₂₀ are each independently hydrogen or 1 to 20 carbon atoms It may be an alkyl group.

As another example, in Formula C, R ₁₄ may be an unsubstituted divalent hydrocarbon group having 1 to 10 carbon atoms, R ₁₅ may be an alkylene group having 1 to 20 carbon atoms, and R ₁₆ is an alkyl group having 1 to 20 carbon atoms. may be a silyl group unsubstituted or substituted with a silyl group, a halogen group, or -COR _g , and R _g is an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, 2 to carbon atoms It may be one selected from the group consisting of a 10 heterocycloalkyl group, a heteroamine group having 2 to 10 carbon atoms, and a disilylaminoalkyl group having 3 to 10 carbon atoms, wherein R ₁₇ to R ₂₀ are each independently hydrogen or 1 to 20 carbon atoms. may be an alkyl group of

As a specific example, the compound represented by Formula C may be at least one selected from the group consisting of compounds represented by the following Formulas C-1 to C-6.

[Formula C-1]

[Formula C-2]

[Formula C-3]

[Formula C-4]

[Formula C-5]

[Formula C-6]

[

[Formula C-7]

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 to 10 moles relative to 1 mole of the neodymium compound in the catalyst composition.

In addition, the denaturation reaction is performed at a temperature of 0 ° C or higher, 30 ° C or higher, 40 ° C or higher, 100 ° C or lower, 90 ° C or lower, 80 ° C or lower, 1 minute or more, 5 minutes or more, 3 hours or less, 2 hours or less, 1 The reaction may be carried out for up to an hour.

Step (S3)

Step (S3) is a step of reacting the modified polymer with a mixture of a phenol-based antioxidant and a diarylamine-based antioxidant. This is an inactivation step for the remaining activated organometallic sites in the modified conjugated diene-based polymer of the modified polymer, and may correspond to a post-treatment step for stabilizing and recovering the modified conjugated diene-based polymer to be finally prepared.

In the present invention, by using a mixture of a phenol-based antioxidant and a diarylamine-based antioxidant, the change over time, which is a problem when an amine-based modifier is used, is effectively suppressed. Diarylamine-based antioxidants can suppress competition when the modified conjugated diene-based polymer is coupled with the unmodified conjugated diene-based polymer through an amine group derived from the amine-based modifier, and this effect can be achieved by using phenolic antioxidants. It can be further maximized by using them together. In addition, by using the diarylamine-based antioxidant and the phenol-based antioxidant together, it is possible to effectively prevent gelation due to oxidation.

In addition, it is possible to prepare a modified conjugated diene-based polymer having better final physical properties by suppressing the exhaustion of amine groups due to the side reaction, which exhibits excellent tensile properties and viscoelastic properties when manufactured as a rubber specimen.

In the present invention, the phenol-based antioxidant may be a compound represented by the following formula (1).

[Formula 1]

In Formula 1,

R ₁ and R ₂ are each independently alkyl having 1 to 6 carbon atoms or —(CH ₂ ) _a S(R _a ), where a is an integer of 1 to 6, R _a is alkyl having 1 to 30 carbons,

X is a direct bond, -(CH ₂ ) _b S- or -(CH ₂ ) _c COO-, wherein b and c are each independently an integer from 1 to 6,

n is an integer of 1 or 4,

When n is 1, R ₃ is alkyl having 1 to 30 carbon atoms,

When n is 4, R ₃ is alkane-tetrayl having 4 to 10 carbon atoms.

The alkane-tetrayl may refer to a linear or branched tetravalent saturated hydrocarbon group, for example, alkane-tetrayl having 4 to 10 carbon atoms includes, but is not limited to, the following functional groups. Specifically, pentaerythrityl having the following structure may be preferably used.

The phenolic antioxidant is 2-methyl-4,6-bis((octylthio)methyl)phenol (2-methyl-4,6-bis((octylthio)methyl)phenol), 2,6-di-t- Butyl-4-methylphenol (2,6-di-t-butyl-4-methylphenol), octadecyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate (octadecyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) and pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate (pentaerythritol tetrakis ( 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) may be at least one selected from the group consisting of, but is not limited thereto.

- 2-methyl-4,6-bis((octylthio)methyl)phenol

- 2,6-di-t-butyl-4-methylphenol

-octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate

- Pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate

In the present invention, the phenolic antioxidant may be 0.05 to 1.0 parts by weight based on 100 parts by weight of the conjugated diene-based monomer, specifically, 0.05 parts by weight or more, 0.10 parts by weight or more, 0.15 parts by weight or more, 1.0 parts by weight or less, 0.7 parts by weight or more. It may be less than or equal to 0.3 parts by weight. When the phenolic antioxidant is less than 0.05 parts by weight, it is difficult to obtain a sufficient deactivation effect, and when it is more than 1.0 parts by weight, excess antioxidant is generated, thereby increasing the production cost and lowering economic efficiency.

The diarylamine-based antioxidant may be a compound represented by the following formula (2).

[Formula 2]

In Formula 2,

R ₄ and R ₅ are each independently hydrogen or alkyl having 1 to 30 carbon atoms.

Specifically, the diarylamine-based antioxidant may be at least one selected from the group consisting of the following Chemical Formulas 2-1 to 2-3, but is not limited thereto.

[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

The diarylamine-based antioxidant may be 0.05 to 1.0 parts by weight based on 100 parts by weight of the conjugated diene-based monomer, specifically, 0.05 parts by weight or more, 0.1 parts by weight or more, 1.0 parts by weight or less, 0.7 parts by weight or less, 0.3 parts by weight or less. can When the amount of the diarylamine-based antioxidant is less than 0.05 parts by weight, it is difficult to sufficiently obtain the effect of inhibiting change over time, and when it exceeds 1.0 parts by weight, there is a risk of gelation due to the use of an excessive amount of antioxidant.

In addition, the molar ratio of the phenol-based antioxidant and the diarylamine-based antioxidant may be 1:0.2 to 1:5, specifically 1:0.2 to 1:3, 1:0.3 to 1:2, 1:0.4 to 1:1.2, 1:0.4 to 1:0.8.

In addition, after step (S3), the modified conjugated diene-based polymer can be obtained by desolving 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.

The modified conjugated diene-based polymer produced by the production method of the present invention is optimized to improve the balance of physical properties such as viscoelasticity, tensile properties and processability of the rubber composition through control of catalyst composition and polymerization conditions during production, molecular weight distribution, and Mooney viscosity It may have characteristics such as

In addition, the modified conjugated diene-based polymer of the present invention is applicable to a rubber composition comprising the same and a molded article prepared therefrom.

The rubber composition may include 0.1 wt% or more and 100 wt% or less of the modified conjugated diene-based polymer, specifically 10 wt% to 100 wt%, and more specifically 20 wt% to 90 wt%. If the content of the modified conjugated diene-based polymer is less than 0.1% by weight, as a result, the improvement effect of abrasion resistance and crack resistance of a molded article manufactured using the rubber composition, such as a tire, 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, butyl rubber, halogenated butyl rubber, etc. may be synthetic rubbers, and any one or mixture of two or more thereof may be used. there is.

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 / g to 180 m / g, and a cetyl trimethyl ammonium bromide (CTAB) adsorption specific surface area of 100 m / g to 200 m It can be /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 silica may be lowered, and if it exceeds 180 m / 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 / 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-trimethyl-1,2-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, or an internal mixer 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, side wall, carcass coated rubber, belt coated rubber, bead filler, cheffer, or bead coated rubber, vibration proof 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.

Example

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

[Preparation Example 1: Preparation of amine-based modifier]

Preparation 1-1

In a solution of 2 g of ethyl piperidine-3-carboxylate in dichloromethane (CH ₂ Cl ₂ ), 1.77 mL of triethylamine (Et ₃ N) and trimethyl chloride at 0 ° C. Silyl (TMSC1) 1.62 mL was added, and the reaction mixture was stirred at 0° C. for 5 hours. Then, the solvent in the resulting solution was evaporated under reduced pressure, re-dissolved in hexane, and filtered to obtain a compound having the following structure, and ¹ H nuclear magnetic resonance spectroscopy was observed.

¹ H NMR (500 MHz, CDCl ₃ ): δ 4.11-4.08 (m, 2H), δ 3.13-3.11 (m, 2H), δ 2.61-2.54 (m, 2H), δ 2.34-2.32 (m, 1H) , δ 1.74 (m, 2H), δ 1.42 (m, 2H), δ 1.23-1.22 (m, 3H), δ 0.05-0.00 (m, 9H).

Preparation 1-2

In a solution of 5 g of ethyl 6-aminohexanoate HCl in dichloromethane (CH ₂ Cl ₂ ), 18 mL of triethylamine and 1.2-bis(chlorodimethylsilyl)ethane [1.2 -bis(chlorodimethylsilyl)ethane] 13.8 g was added, and the reaction mixture was stirred at 0° C. for 10 minutes, followed by stirring at room temperature for an additional day. Then, after adding hexane to the resulting solution, the solvent was evaporated in vacuo, re-dissolved in ethanol/hexane (1:1) solution, and filtered to obtain a compound of the following structure.

¹ H NMR (500 MHz, CDCl ₃ ) δ 4.10 (m, 2H), δ 2.74 (m, 2H), δ 2.26 (m, 2H), δ 1.60 (m, 2H), δ 1.37 (m, 2H), δ 1.25 (m, 6H), δ 0.65 (s, 4H), δ 0.01 (s, 12H).

Preparation Example 2: Preparation of phenolic antioxidant

Irganox 1520 from BASF having the following structure was purchased and prepared.

Preparation Example 3: Preparation of diarylamine-based antioxidant

Irganox 5057 from BASF having the following structure was purchased and prepared.

Example 1: Preparation of modified conjugated diene-based polymer

Hexane (4.173 kg) and 1,3-butadiene (500 g) were added to a 10L reactor under argon conditions, and the temperature was raised to 70°C. Hexane solution containing 0.40 mmol of neodymium versatate (NdV), 16.0 mmol of diisobutylaluminum hydride (DIBAH), 0.96 mmol of diethylaluminum chloride, and 8.0 mmol of 1,3-butadiene , After adding the catalyst composition prepared through the reaction of a toluene solution containing 40.0 mmol of methylaluminoxane (MAO), polymerization was carried out for 50 minutes until the conversion rate was about 100%.

Thereafter, a hexane solution containing the denaturant of Preparation Example 1-1 at a concentration of 10% was added before the polymerization was terminated, and then the denaturation reaction was performed by stirring at 50 to 80° C. for 10 to 60 minutes.

A hexane solution containing 1.0 g of a polymerization terminator and a mixture of the antioxidants of Preparation Examples 2 and 3 in a molar ratio of 2: 1 were added to a hexane solution in which 30% was dissolved to terminate the reaction, and the The resulting polymer was put into hot water heated with steam, stirred to remove the solvent, and then roll-dried to remove the residual amount of solvent and water to prepare a modified conjugated diene-based polymer.

Example 2, Comparative Examples 1 to 5

A modified conjugated diene-based polymer was prepared in the same manner as in Example 1, except that the types of modifiers and antioxidants were changed as shown in Table 1 below.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 denaturant Preparation 1-1 Preparation 1-2 - Preparation 1-1 Preparation 1-2 Preparation 1-1 Preparation 1-2 antioxidant Preparation Example 2 + Preparation Example 3 Preparation Example 2 + Preparation Example 3 Preparation 2 Preparation 2 Preparation 2 Preparation 3 Preparation 3

Experimental Example 1

(1) Measurement of Mooney viscosity change (ΔMV) over time

For each polymer, the Mooney viscosity (MV, ML1+4, @100°C) immediately after preparation was measured using a large rotor with a Monsanto MV2000E at 100° C. and a rotor speed of 2±0.02 rpm.

In addition, Mooney viscosity (MV) was measured in the same manner after being left in an oven at 70° C. for 5 days, and the Mooney viscosity difference (ΔMV) was calculated immediately after production and after leaving for 5 days.

(2) Measurement of beta value change over time (Δβ-value)

The beta value (β-value) was measured using the 　 measurement method developed by The Goodyear Tire & Rubber Company. As a measuring device, a Rubber Process Analyzer (RPA2000, AlphaTechnologies) was used. Specifically, each polymer was subjected to a frequency sweep with a strain of 7% at 100°C. At this time, the frequency was set to 2, 5, 10, 20, 50, 100, 200, 500, 1,000, and 2,000 cpm, and the beta value was obtained by calculating the slope of Log(1/tan delta) vs Log(Freq.).

In addition, the beta value was measured in the same manner after being left in an oven at 70° C. for 5 days, and the beta value change (Δβ-value) was calculated immediately after preparation and after leaving it for 5 days.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 MV immediately after manufacturing 56 56 40 55 60 55 60 after 5 days 58 61 40 61 70 65 74 △MV 2 5 0 6 10 10 14 β-value immediately after manufacturing 0.26 0.23 0.16 0.25 0.23 0.25 0.23 after 5 days 0.25 0.20 0.16 0.20 0.17 0.17 0.16 △β-value 0.01 0.03 0 0.05 0.06 0.08 0.07

As shown in Table 2, the modified conjugated diene-based polymer of Examples prepared by mixing a phenol-based antioxidant and a diarylamine-based antioxidant according to the production method of the present invention has Mooney viscosity and β-value even after a certain period of time has elapsed. It was confirmed that there was an effect of preventing the change of the physical properties of the polymer with the passage of time because the fluctuation range was not large.

On the other hand, in Comparative Example 2 using only the phenol-based antioxidant while using the same denaturant in Preparation Example 1-1 and Comparative Example 4 using only the diarylamine-based antioxidant, the Mooney viscosity and β-value change compared to Example 1 Similarly, in the case of Comparative Example 3 using only the phenol-based antioxidant while using the same preparation example 1-2 modifier and Comparative Example 5 using only the diarylamine-based antioxidant, the Mooney viscosity and β- value appeared to be large.

Experimental Example 2

In order to comparatively analyze the physical properties of the rubber composition containing each modified conjugated diene-based polymer prepared in Examples and Comparative Examples and molded articles prepared therefrom, rubber specimens were prepared as follows.

Specifically, as raw rubber, 60 parts by weight of graphite and 15 parts by weight of process oil, 2 parts by weight of antioxidant (TMDQ), oxidation based on 100 parts by weight of the modified conjugated diene-based polymer prepared in Examples and Comparative Examples as raw rubber. Each rubber composition was prepared by mixing 3 parts by weight of zinc (ZnO) and 2 parts by weight of stearic acid.

Thereafter, 2 parts by weight of sulfur, 2 parts by weight of a vulcanization accelerator (CZ) and 0.5 parts by weight of a vulcanization accelerator (DPG) were added to each rubber composition, and vulcanized at 160° C. for 25 minutes to prepare a rubber specimen.

(1) Tensile properties

Modulus (300% modulus, kg f/cm ² ), tensile strength, kg f/cm ² ), elongation at 300% elongation according to ASTM D412 after vulcanization at 150° C. for t90 minutes for the rubber composition (elongation) was measured. For each of the measured values, the measured value of Comparative Example 1 was set to 100 and indexed through the following formula. The higher the number, the better the mechanical properties.

- Index = (measured value/reference value) × 100

(2) Viscoelastic properties

A dynamic mechanical analyzer from TA was used. The tanδ value was measured by changing the strain at a frequency of 10 Hz and each measurement temperature (50~70°C) in torsion mode. The lower the tanδ value at high temperature (50~70℃), the smaller the hysteresis loss, and it means that the tire has excellent low rolling resistance, that is, low fuel efficiency.

For each of the measured values, the measured value of Comparative Example 1 was set to 100 and indexed through the following formula.

- Index = (reference value/measurement value) × 100

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 tensile properties M-300% 115 113 100 114 111 113 110 tensile strength 111 108 100 109 104 108 105 elongation 103 101 100 100 98 101 99 Viscoelastic properties Tan δ at 50~70℃ 120 122 100 116 118 116 119

As summarized in Table 3, Example 1, in which a modified conjugated diene-based polymer was prepared according to the manufacturing method of the present invention using a modifier of Preparation Example 1-1, has superior tensile properties and viscoelastic properties compared to Comparative Examples 2 or 4, and , Similarly, Example 2 using Preparation Example 1-2 modifier also showed that the tensile properties and viscoelastic properties were improved compared to Comparative Examples 3 or 5.

Experimental Example 3

After the rubber composition or rubber specimen prepared in Experimental Example 2 was left at room temperature for 60 days, tensile properties and viscoelastic properties were evaluated in the same manner as in Experimental Example 2.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 tensile properties M-300% 109 110 100 106 107 105 104 △M-300% 6 0 0 8 4 10 6 tensile strength 106 103 100 105 99 99 100 △ Tensile strength 4 5 0 4 5 9 5 elongation 97 98 100 98 95 96 95 △ elongation 0 One 0 2 3 5 4 Viscoelastic properties Tan δ at 50~70℃ 118 119 100 110 108 107 109 △Tan δ 2 3 0 6 10 9 10

As summarized in the above table, the modified conjugated diene-based polymer of Example 1 showed that the change with time was suppressed compared to Comparative Examples 2 and 4 even after processing into a rubber specimen, and the modified conjugated diene-based polymer of Example 2 was similarly It was found that the change in physical properties over time was reduced compared to Comparative Examples 3 and 5.

Claims (11)

(S1) 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;
(S2) preparing a modified polymer by reacting the active polymer with an amine-based modifier; and
(S3) reacting the modified polymer with a mixture of a phenol-based antioxidant and a diarylamine-based antioxidant;
A method for producing a modified conjugated diene-based polymer comprising a.
The method according to claim 1,
The amine-based modifier is a compound comprising an amine group protected with trialkylsilyl and a functional end group capable of reacting with the active polymer, the method for producing a modified conjugated diene-based polymer.
The method according to claim 1,
The method for producing a modified conjugated diene-based polymer wherein the phenol-based antioxidant is a compound represented by the following formula (1):
[Formula 1]

In Formula 1,
R ₁ and R ₂ are each independently alkyl having 1 to 6 carbon atoms or -(CH ₂ ) _a S(R _a )-, where a is an integer from 1 to 6, R _a is alkyl having 1 to 30 carbon atoms; ,
X is a direct bond, -(CH ₂ ) _b S- or -(CH ₂ ) _c COO-, wherein b and c are each independently an integer from 1 to 6,
n is an integer of 1 or 4,
When n is 1, R ₃ is alkyl having 1 to 30 carbon atoms,
When n is 4, R ₃ is alkane-tetrayl having 4 to 10 carbon atoms.
4. The method according to claim 3,
The phenolic antioxidant is 2-methyl-4,6-bis((octylthio)methyl)phenol (2-methyl-4,6-bis((octylthio)methyl)phenol), 2,6-di-t- Butyl-4-methylphenol (2,6-di-t-butyl-4-methylphenol), octadecyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate (octadecyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) and pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate (pentaerythritol tetrakis ( 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) A method for producing at least one modified conjugated diene-based polymer selected from the group consisting of:
The method according to claim 1,
Method for producing a modified conjugated diene-based polymer wherein the diarylamine-based antioxidant is a compound represented by the following Chemical Formula 2:
[Formula 2]

In Formula 2,
R ₄ and R ₅ are each independently hydrogen or alkyl having 1 to 30 carbon atoms.
6. The method of claim 5,
The diarylamine-based antioxidant is a method for producing at least one modified conjugated diene-based polymer selected from the group consisting of the following Chemical Formulas 2-1 to 2-3.
[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

The method according to claim 1,
The molar ratio of the phenol-based antioxidant and the diarylamine-based antioxidant is 1:0.2 to 1:5.
The method according to claim 1,
The phenol-based antioxidant is 0.05 to 1.0 parts by weight based on 100 parts by weight of the conjugated diene-based monomer.
The method according to claim 1,
The diarylamine-based antioxidant is a method for producing a modified conjugated diene-based polymer in an amount of 0.05 to 1.0 parts by weight based on 100 parts by weight of the conjugated diene-based monomer.
The method according to claim 1,
The catalyst composition is a method for producing a modified conjugated diene-based polymer comprising a neodymium compound, an alkylating agent, a halide and a conjugated diene-based monomer.
The method according to claim 1,
The conjugated diene-based monomer is 1,3-butadiene, isoprene, 1,3-pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, At least one modified conjugated diene selected from the group consisting of 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene and 2,4-hexadiene Method for producing a polymer-based polymer.