KR20210108677A - Conjugated-diene based copolymer, method for preparing the same and rubber composition comprising the same - Google Patents

Abstract

The present invention relates to a conjugated diene-based copolymer. More specifically, provided are a conjugated diene-based copolymer including a unit derived from a compound selected from a group consisting of a unit derived from a conjugated diene-based monomer, a unit derived from an aromatic vinyl monomer, and a compound represented by chemical formulas 1 to 4 (see in the specification), a manufacturing method thereof, and a rubber composition including the same.

Description

Conjugated diene-based copolymer, manufacturing method thereof, and rubber composition comprising the same

The present invention relates to a conjugated diene-based copolymer, and more particularly, to a conjugated diene-based copolymer, a method for preparing the same, and a rubber composition comprising the same.

Recently, as interest in eco-friendly technologies is on the rise, interest in eco-friendly tires is also increasing in tires applied to automobiles. The eco-friendly tire is directly related to fuel economy reduction through fuel saving of automobiles, and is intended to reduce unnecessary combustion consumption by reducing the rolling resistance of the tire, and to reduce the emission of carbon dioxide, which is the main cause of global warming.

Therefore, as a rubber material used for such eco-friendly tires, a conjugated diene-based polymer having low rolling resistance, excellent abrasion resistance and tensile properties, and also having adjustment stability typified by wet road resistance is required.

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

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

These tire rubbers are generally mixed with fillers such as carbon black and silica to supplement the physical properties of rubber. Among them, SBR prepared by solution polymerization has a polar group at the end of the polymer through anionic polymerization. Although it is used to improve affinity with the filler by introducing a monomer, there is a problem in that abrasion resistance is lowered compared to SBR prepared by emulsion polymerization. In addition, SBR prepared by emulsion polymerization has a problem in that it is difficult to introduce a repeating unit derived from a desired monomer into a specific part due to the characteristics of emulsion polymerization, so it is difficult to introduce a polar group to the polymer chain to improve affinity with a filler.

Accordingly, there was an attempt to improve the affinity with the filler by introducing a monomer having an amine group onto the SBR prepared by emulsion polymerization, but in order to introduce the monomer having an amine group into the SBR, a monomer having an amine group is mixed and emulsion polymerization In this case, there was a problem in that polymerization is difficult because the amine acts as a polymerization terminator in the free radical polymerization reaction.

Therefore, there is a need for research on introducing an amine group into the SBR in order to increase the affinity with the filler.

KR 10-0282964 B

The problem to be solved in the present invention is to secure the abrasion resistance of the rubber composition by polymerizing the conjugated diene-based copolymer by emulsion polymerization in order to solve the problems mentioned in the technology that is the background of the invention, It is to improve the rolling resistance properties of the rubber composition by imparting an amine group having high affinity with the filler.

That is, the present invention has been devised to solve the problems of the technology that is the background of the invention, and by introducing an amine group in the conjugated diene-based copolymer prepared by emulsion polymerization to improve affinity with the filler, including the An object of the present invention is to provide a conjugated diene-based copolymer capable of improving the rolling resistance properties of a rubber composition, a method for preparing the same, and a rubber composition comprising the same.

According to an embodiment of the present invention for solving the above problems, the present invention provides at least one selected from the group consisting of a unit derived from a conjugated diene-based monomer, a unit derived from an aromatic vinyl-based monomer, and a compound represented by the following Chemical Formulas 1 to 4 Provided is a conjugated diene-based copolymer including a compound-derived unit.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4, R ₁ and R ₂ are each independently N(R ₇ R ₈ ), R ₃ to R ₆ are each independently N(R ₉ ), and R ₇ to R ₉ each independently represents a hydrogen or an amine group, and * represents a bonding position.

In addition, the present invention comprises the steps of preparing a polymer by emulsion polymerization of a conjugated diene-based monomer, an aromatic vinyl-based monomer and a maleimide-based monomer; And it provides a method for preparing a conjugated diene-based copolymer comprising the step of deimidizing the polymer.

In addition, the present invention provides a rubber composition comprising the conjugated diene-based copolymer and a filler.

The present invention secures abrasion resistance and processability of a rubber composition containing the conjugated diene-based copolymer as a raw material rubber component by easily introducing an amine group in the conjugated diene-based copolymer polymerized by emulsion polymerization, and at the same time, rolling resistance characteristics This has an improvement effect.

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 must properly understand the concept of the term in order to best describe his invention. Based on the principle that can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

In the present invention, the term 'monomer-derived unit' may indicate a component, structure, or material itself derived from a monomer, and during polymerization of a polymer, the input monomer participates in a polymerization reaction to mean a unit formed in the polymer. can

In the present invention, the term 'latex' may mean that a polymer or copolymer polymerized by polymerization is present in a dispersed form in water, and as a specific example, fine particles of a polymer or copolymer in rubber polymerized by emulsion polymerization. may mean that it exists in a dispersed form in water in a colloidal state.

In the present invention, the term 'rubber' refers to a plastic material having elasticity, and may mean rubber, elastomer, or synthetic latex.

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

According to the present invention, a conjugated diene-based copolymer is provided. The conjugated diene-based copolymer may include at least one compound-derived unit selected from the group consisting of a conjugated diene-based monomer-derived unit, an aromatic vinyl-based monomer-derived unit, and a compound represented by the following Chemical Formulas 1 to 4.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4, R ₁ and R ₂ are each independently N(R ₇ R ₈ ), R ₃ to R ₆ are each independently N(R ₉ ), and R ₇ to R ₉ each independently represents a hydrogen or an amine group, and * represents a bonding position.

According to an embodiment of the present invention, the conjugated diene-based monomer for forming the unit derived from the conjugated diene-based monomer included in the conjugated diene-based copolymer is 1,3-butadiene, 2,3-dimethyl-1,3-butadiene. from the group consisting of , piperylene, 3-butyl-1,3-octadiene, isoprene, 2-phenyl-1,3-butadiene and 2-halo-1,3-butadiene (halo means halogen atom). It may include one or more selected. As a specific example, the conjugated diene monomer may be 1,3-butadiene.

The content of the conjugated diene-based monomer-derived unit may be 30 wt% to 80 wt%, 40 wt% to 75 wt%, or 40 wt% to 70 wt%, based on the total content of the conjugated diene-based copolymer, in this range The processability of the conjugated diene-based copolymer is excellent in the interior, and the impact strength, tensile properties and viscoelastic properties of a rubber composition containing it as a raw rubber component are excellent.

According to an embodiment of the present invention, the aromatic vinyl-based monomer for forming the unit derived from the aromatic vinyl-based monomer included in the conjugated diene-based copolymer is styrene, α-methylstyrene, 3-methylstyrene, 4-methylstyrene, At least one selected from the group consisting of 4-propylstyrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4-(p-methylphenyl)styrene, and 1-vinyl-5-hexylnaphthalene may be included. As a more specific example, the aromatic vinyl-based monomer may be styrene.

The content of the aromatic vinyl-based monomer-derived unit may be 20 wt% to 60 wt%, 20 wt% to 50 wt%, or 20 wt% to 40 wt%, based on the total content of the conjugated diene-based copolymer, and within this range While improving the processability of the conjugated diene-based copolymer composition, there is an effect of preventing a decrease in mechanical properties of the rubber composition containing the conjugated diene-based copolymer as a raw material rubber component.

According to an embodiment of the present invention, in the compounds represented by Chemical Formulas 1 to 4 included in the conjugated diene-based copolymer, * may indicate a bonding position. Specifically, when at least one compound-derived unit selected from the group consisting of compounds represented by Chemical Formulas 1 to 4 is positioned in the conjugated diene-based copolymer, the * is a chemically bonded position in the conjugated diene-based copolymer. can represent However, when one or more compound-derived units selected from the group consisting of compounds represented by Chemical Formulas 1 to 4 are located at one end of the conjugated diene-based copolymer, any one of the * is chemical in the conjugated diene-based copolymer. may represent a bonding position, and the other may represent hydrogen.

As an example, in Formula 1, _{at least one of R 7} and R ₈ may be an amine group. As another example, in Formula 2, R ₉ may be an amine group.

As another example, in Formula 3, R ₉ may be hydrogen.

As another example, in Formula 4, R ₉ may be hydrogen.

As a specific example, the conjugated diene-based copolymer may include a unit derived from a conjugated diene-based monomer, a unit derived from an aromatic vinyl-based monomer, and a unit derived from a compound represented by Formula 1 below.

The content of one or more compound-derived units selected from the group consisting of compounds represented by Formulas 1 to 4 is 0.1 wt% to 15 wt%, 3 wt% to 12 wt%, or 5 wt% based on the total content of the conjugated diene-based copolymer % to 10% by weight, and it is possible to improve the affinity between the conjugated diene-based copolymer and the filler within this range, thereby improving the viscoelastic properties of the rubber composition including the conjugated diene-based copolymer as a raw rubber component has the effect of making In particular, the affinity with carbon black and silica can be improved, and the rolling resistance property can be effectively improved.

According to an embodiment of the present invention, the Mooney viscosity (MV) at 100 ° C. of the conjugated diene-based copolymer may be 20 to 150, 30 to 100, or 30 to 60, and within this range, the rubber While the composition has excellent processability and productivity, there is an effect of excellent mechanical properties.

According to the present invention, there is provided a manufacturing method for preparing the conjugated diene-based copolymer. The method for preparing the conjugated diene-based copolymer includes preparing a polymer by emulsion polymerization of a conjugated diene-based monomer, an aromatic vinyl-based monomer and a maleimide-based monomer; and de-imidizing the polymer.

According to an embodiment of the present invention, in the step of preparing the polymer, the method for preparing a conjugated diene-based copolymer includes injecting a main monomer mixture including a conjugated diene-based monomer, an aromatic vinyl-based monomer and a maleimide-based monomer into a reactor. It can be carried out by a method of emulsion polymerization.

The conjugated diene-based monomer is, for example, 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-1,3-octadiene, isoprene, 2-phenyl-1, It may include one or more selected from the group consisting of 3-butadiene and 2-halo-1,3-butadiene (halo means a halogen atom.).

The content of the conjugated diene-based monomer may be 30 wt% to 80 wt%, 40 wt% to 75 wt%, or 40 wt% to 70 wt%, based on the total content of the main monomer mixture, and the conjugated diene within this range The processability of the copolymer-based copolymer is excellent, and the impact strength, tensile properties and viscoelastic properties of a rubber composition containing it as a raw rubber component are excellent.

The aromatic vinyl monomer is, for example, styrene, α-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4-(p-methylphenyl) It may include at least one selected from the group consisting of styrene and 1-vinyl-5-hexylnaphthalene. As a more specific example, the aromatic vinyl-based monomer may be styrene.

The content of the aromatic vinyl monomer may be 20 wt% to 60 wt%, 20 wt% to 50 wt%, or 20 wt% to 40 wt%, based on the total content of the main monomer mixture, and the conjugated diene within this range While improving the processability of the copolymer composition, there is an effect of preventing a decrease in mechanical properties of the rubber composition containing the conjugated diene-based copolymer as a raw rubber component.

The maleimide-based monomer may be, for example, maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-cyclohexylmaleimide, or N-phenylmaleimide. Mead, N-toluylmaleimide, N-xylylmaleimide, N-naphthylmaleimide, Nt-butylmaleimide, N-orsochlorphenylmaleimide, N-orsomethoxyphenylmaleimide and N-olsobro It may include one or more selected from the group consisting of mophenylmaleimide. As a specific example, the maleimide-based monomer may be N-phenylmaleimide.

The content of the maleimide-based monomer may be 0.1 wt% to 15 wt%, 3 wt% to 12 wt%, or 5 wt% to 10 wt%, based on the total content of the main monomer mixture, within this range the polymer to be described later A rubber composition comprising the conjugated diene-based copolymer as a raw rubber component by improving affinity with carbon black and silica through which an amine group can be formed in the conjugated diene-based copolymer through the step of deimidizing the It has the effect of improving the rolling resistance characteristics of

According to an embodiment of the present invention, in the step of preparing the polymer, during emulsion polymerization, a polymerization initiator, an emulsifier, a polymerization terminator, ion-exchanged water, a molecular weight regulator, The emulsion polymerization method may be performed in a state in which additives such as an activator and a redox catalyst are added.

Examples of the polymerization initiator include inorganic peroxides such as sodium persulfate, potassium persulfate, ammonium persulfate, potassium perphosphate, and hydrogen peroxide; Diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, cumene hydroperoxide, p-methane hydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, acetyl peroxide, isobutyl peroxide organic peroxides such as , octanoyl peroxide, benzoyl peroxide, 3,5,5-trimethylhexanol peroxide, and t-butyl peroxy isobutylate; Alternatively, nitrogen compounds such as azobis isobutyronitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, and azobisisobutyronitrile (butyric acid) methyl may be used alone or in combination of two or more. have.

Here, when the organic peroxide or the inorganic peroxide is used as the polymerization initiator, it may be used in combination with a reducing agent. The reducing agent includes a compound containing a metal ion in a reduced state such as ferrous sulfate and cuprous naphthenate; a sulfonic acid compound such as sodium methanesulfonate; or an amine compound such as dimethylaniline alone or in combination of two or more Can be used.

The polymerization terminator is hydroxylamine, hydroxyamine sulfate, diethyl hydroxyamine, hydroxyamine sulfonic acid and its alkali metal ion, sodium dimethyl dithiocarbamate, hydroquinone derivatives, hydroxydiethylbenzene dithiocarboxylic acid and aromatic hydroxy dithio carboxylic acids such as hydroxy dibutyl benzene dithio carboxylic acid and the like.

Water may be used as the ion-exchange water.

Examples of the emulsifier include nonionic emulsifiers such as polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ester, and polyoxyethylene sorbitan alkyl ester; myristic acid, palmitic acid, oleic acid, rosin acid, Salts of fatty acids such as linolenic acid and stearic acid, alkylbenzenesulfonates such as sodium dodecylbenzenesulfonate, higher alcohol sulfate esters, and anionic emulsifiers such as alkylsulfosuccinates; alkyltrimethylammonium chloride, dialkylammonium chloride, benzyl Cationic emulsifiers such as ammonium chloride; or copolymerizable emulsifiers such as sulfo esters of α,β-unsaturated carboxylic acids, sulfate esters of α,β-unsaturated carboxylic acids, and sulfoalkyl aryl ethers alone or in combination of two or more Can be used.

Examples of the molecular weight modifier include mercaptans such as a-methylstyrene dimer, t-dodecyl mercaptan, n-dodecyl mercaptan, and octyl mercaptan; halogenated hydrocarbons such as carbon tetrachloride, methylene chloride and methylene bromide; Alternatively, a sulfur-containing compound such as tetraethyl diuram disulfide, dipentamethylene diuram disulfide, or diisopropylxanthogen disulfide may be used.

As the activator, sodium hydrosulfite, sodium formaldehyde sulfoxylate, sodium ethylenediamine tetraacetate, ferrous sulfate, lactose, dextrose, sodium linoleate, or sodium sulfate may be used alone or in combination of two or more.

As the redox catalyst, sodium formaldehyde sulfoxylate, ferrous sulfate, disodium ethylenediamine tetraacetate, or cupric sulfate may be used alone or in combination of two or more.

According to an embodiment of the present invention, the step of preparing the polymer may be performed at a temperature of 5 °C to 100 °C, 10 °C to 90 °C, or 10 °C to 80 °C.

According to an embodiment of the present invention, the polymer prepared in the step of preparing the polymer includes a copolymer in the form of a latex comprising a unit derived from a conjugated diene-based monomer, a unit derived from an aromatic vinyl-based monomer, and a unit derived from a maleimide-based monomer. can do.

Since the polymer prepared in the step of preparing the polymer is in a latex state, it is possible to obtain an acrylic copolymer latex that is mixed (or dispersed) uniformly while being easily mixed.

According to an embodiment of the present invention, the step of deimidizing the polymer comprises the steps of the maleimide-based monomer in the copolymer including the conjugated diene-based monomer-derived unit, the aromatic vinyl-based monomer-derived unit and the maleimide-based monomer-derived unit. By modifying the terminal with an amine group, it may be a step for introducing an amine group in the conjugated diene-based copolymer.

Conventionally, a monomer having an amine group was mixed to improve the affinity of the conjugated diene-based copolymer and the filler prepared by emulsion polymerization. As this polymerization terminator, there was a problem that polymerization did not proceed smoothly.

Therefore, in the present invention, when preparing the conjugated diene-based copolymer, the conjugated diene-based monomer and the aromatic vinyl-based monomer and the maleimide-based monomer are emulsion-polymerized to prepare a polymer, and the prepared polymer is deimidized, By modifying the terminal of the maleimide-based monomer with an amine group, it is possible to prepare a conjugated diene-based copolymer into which an amine group is introduced while smoothly proceeding an emulsion polymerization.

According to an embodiment of the present invention, the step of deimidizing the polymer may be performed by including a reducing agent and an acid.

The reducing agent may include, for example, at least one selected from the group consisting of hydrazine and hydrazine hydrate. As a specific example, the reducing agent may be hydrazine hydrate.

In the step of deimidizing the polymer, the reducing agent may be added in an amount of 1 part by weight to 30 parts by weight, 1 part by weight to 20 parts by weight, or 1 part by weight to 10 parts by weight based on 100 parts by weight of the total polymer based on the solid content. By adding a reducing agent within the above range in the step of deimidizing the polymer, an amine group in the conjugated diene-based copolymer may be formed.

The acid may include at least one selected from the group consisting of hydrochloric acid, nitric acid and sulfuric acid. As a specific example, the acid may include hydrochloric acid.

In the step of deimidizing the polymer, the acid may be added in an amount of 0.1 parts by weight to 10 parts by weight, 0.1 parts by weight to 5 parts by weight, or 0.2 parts by weight to 1 part by weight based on 100 parts by weight of the entire polymer based on the solid content. By adding an acid within the above range in the step of deimidizing the polymer, an amine group in the conjugated diene-based copolymer can be easily formed.

Deimidizing the polymer may be performed under a temperature condition of 10 °C to 90 °C. For example, the step of deimidizing the polymer may be performed under a temperature condition of 30 °C to 90 °C, 50 °C to 90 °C, or 80 °C to 90 °C. By deimidizing the polymer under the above temperature conditions, an amine group in the conjugated diene-based copolymer can be easily formed.

In addition, the step of deimidizing the polymer may be performed by adding a reducing agent and an acid to the polymer in the latex phase and then stirring for 12 to 36 hours under the above temperature conditions. In particular, since the deimidization reaction is performed as it is in a dispersed condition in an aqueous phase rather than a method of dissolving the polymer again in a solvent and denaturing it, the effect of improving the working environment and simplifying the product process can be realized.

In this way, by emulsion polymerization of a conjugated diene-based monomer, an aromatic vinyl-based monomer, and a maleimide-based monomer to prepare a polymer, and deimidizing the polymer to prepare a conjugated diene-based copolymer, the monomer containing an amine group is directly synthesized. It is possible to form an amine group in the conjugated diene-based copolymer even without mixing. Through this, it is possible to improve the rolling resistance property by improving the affinity with the filler of the rubber composition using the conjugated diene-based copolymer including the amine group as the raw rubber.

According to an embodiment of the present invention, the method for preparing the conjugated diene-based copolymer includes aggregation, aging, dehydration and drying steps to obtain the conjugated diene-based copolymer composition latex obtained by emulsion polymerization in powder form. may include.

In addition, according to the present invention, there is provided a rubber composition comprising a raw rubber containing the conjugated diene-based copolymer. According to an embodiment of the present invention, the raw rubber may be one comprising the conjugated diene-based copolymer in an amount of 10 wt% to 100 wt%, 50 wt% to 100%, or 50 wt% to 90 wt%, , within this range, mechanical properties such as tensile strength and abrasion resistance are excellent, and there is an effect of excellent balance between the physical properties.

In addition, according to an embodiment of the present invention, the raw rubber may further include one or more rubber components selected from the group consisting of natural rubber and synthetic rubber, if necessary, in addition to the conjugated diene-based copolymer composition, When the rubber component may be included in an amount of 10 wt% to 90 wt%, 10 wt% to 70 wt%, or 10 wt% to 40 wt% with respect to the total content of the raw rubber.

The rubber component may be, for example, natural rubber or synthetic rubber, and specific examples thereof include natural rubber (NR) including cis-1,4-polyisoprene; Modified natural rubbers such as epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber, which 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. have.

According to an embodiment of the present invention, the rubber composition may include 1 part by weight to 200 parts by weight, 5 parts by weight to 150 parts by weight, or 10 parts by weight to 120 parts by weight of the filler based on 100 parts by weight of the raw rubber.

As a specific example, the filler may include at least one selected from the group consisting of a carbon black filler and a silica-based filler. As a specific example, the filler may be a carbon black filler. As a more specific example, the filler may be used by mixing a carbon black filler and a silica-based filler. In this case, it is possible to improve the abrasion resistance in addition to the rolling resistance characteristics.

The carbon black filler may include, for example, at least one selected from the group consisting of channel black, furnace black, thermal black and acetylene black. When the carbon black is used as a filler, the rolling resistance property of the rubber composition is improved due to excellent affinity with the amine group in the conjugated diene-based copolymer, and the amount is increased during rubber compounding to reduce the unit cost of the rubber compound, improve processability, Mechanical strength such as dimensional stabilization, tensile strength, tear strength, and abrasion resistance can be improved.

The silica-based filler may be, for example, at least one selected from the group consisting of wet silica, fumed silica, calcium silicate, aluminum silicate and colloidal silica, and preferably has an effect of improving fracture properties and wet grip. It may be wet silica with the best compatibility effect.

As another example, when silica is used as the filler, a silane coupling agent for improving reinforcing and low heat generation may be used together, and as a specific example, the silane coupling agent is bis(3-triethoxysilylpropyl)tetrasulfide , bis(3-triethoxysilylpropyl)trisulfide, bis(3-triethoxysilylpropyl)disulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(3-trimethoxysilyl) propyl) tetrasulfide, bis(2-trimethoxysilylethyl)tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-Mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide Feed, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-trimethoxysilylpropylbenzothiazolyltetrasulfide, 3-triethoxysilylpropylbenzolyltetrasulfide, 3-triethoxysilylpropylmethacrylate monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, bis(3-diethoxymethylsilylpropyl)tetrasulfide, 3-mercaptopropyldimethoxymethyl It may be silane, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide or dimethoxymethylsilylpropylbenzothiazolyltetrasulfide, and any one or a mixture of two or more thereof may be used. Preferably, in consideration of the reinforcing improvement effect, it may be bis(3-triethoxysilylpropyl)polysulfide or 3-trimethoxysilylpropylbenzothiazyltetrasulfide.

The rubber composition may further optionally include one or more additives selected from the group consisting of an anti-aging agent, a light stabilizer, a plasticizer, a lubricant, an adhesive, a flame retardant, an anti-mold agent, an antistatic agent, and a colorant.

The mixing of the rubber composition may be made by a method such as roll mixing, Van Barry mixing, screw mixing, or solution mixing.

The rubber composition according to the present invention can be made to have a required shape through a molding or extrusion process after crosslinking is completed, or an article can be manufactured by curing simultaneously or subsequent to crosslinking.

Examples of the article include tire members such as tires, tire treads, under treads, sidewalls, carcass coated rubber, belt coated rubber, bead filler, chaff, or bead coated rubber, rubber for engine mounts, and transmission seals. , engine members such as crankshaft seals, and various industrial rubber products such as vibration-proof rubber, belt conveyors, hoses, and the like.

Hereinafter, the present invention will be described in more detail by way of Examples. However, the following examples are intended to illustrate the present invention, and it is clear to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention, and the scope of the present invention is not limited thereto.

Example

Example 1

<Production of polymer>

To 100 parts by weight of a monomer mixture consisting of 51% by weight of 1,3-butadiene, 48% by weight of styrene and 1% by weight of N-phenylmaleimide (TCI, >97%) in a nitrogen-substituted polymerization reactor, sodium dodecylbenzene sulfo Emulsion polymerization was initiated at 10° C. by mixing 3 parts by weight of SDBS, 0.05 parts by weight of p-methane hydroperoxide, 0.5 parts by weight of t-dodecyl mercaptan, and 200 parts by weight of ion-exchanged water. Then, when the polymerization conversion reached 60%, the polymerization was stopped to obtain a polymer in the form of latex.

<Preparation of conjugated diene-based copolymer>

1.5 parts by weight of hydrogene hydrate (Hydrazine monohydrate, Sigma-Aldrich Chem. Co.) and 0.32 parts by weight of hydrochloric acid were added with respect to 100 parts by weight of the obtained polymer, and the temperature was raised to 80° C. and reacted for 24 hours to deimidize. A conjugated diene-based copolymer in the form of latex was prepared.

Then, 37.5 parts by weight of extender oil and 0.5 parts by weight of antioxidant (6PPD) were added to the prepared conjugated diene-based copolymer latex, 1 part by weight of aluminum sulfate was added to 1000 parts by weight of ion-exchanged water, and the temperature was raised to 70 ° C. It was coagulated in water, aged for 20 minutes, and then cooled to obtain a coagulated product, which was washed 2 to 3 times with ion-exchanged water to remove residual monomers, and then dehydrated using a filter. Thereafter, it was dried in an oven at 100° C. for 1 hour to obtain a powdered conjugated diene-based copolymer.

As a result of measuring the obtained conjugated diene-based copolymer by H-NMR, it was found that the benzene peaks of styrene and N-phenylmaleimide measured at around 7 ppm decreased, and as a result of FT-IR measurement, 3200 cm ^-1 Through the observation of a peak in the range of to 3500 cm ^{-1 It} was confirmed that the structures of Chemical Formulas 1-1 and 2-1 were formed in the conjugated diene-based copolymer. Also, as a result of H-NMR measurement, it was confirmed that the structures of Chemical Formulas 3-1 and 4-1 having resonance structures were formed in the conjugated diene-based copolymer through the observation of a single peak near 8.9 ppm.

[Formula 1-1]

[Formula 2-1]

[Formula 3-1]

[Formula 4-1]

<Preparation of rubber specimen>

The rubber composition was prepared through the processes of first stage kneading, second stage kneading, and third stage kneading.

In the first stage kneading, 40 parts by weight of carbon black, 40 parts by weight of silica, and bis as a silane coupling agent, based on 110 parts by weight of the obtained powdery conjugated diene-based copolymer, using a Banbari mixer equipped with a temperature control device. (3-triethoxysilylpropyl)tetrasulfide 3.2 parts by weight, process oil (TDAE) 6 parts by weight, antioxidant (TMDQ) 2.0 parts by weight, antioxidant (6PPD) 2.0 parts by weight, zinc oxide (ZnO) ) 3.0 parts by weight, 2.0 parts by weight of stearic acid, and 1.0 parts by weight of wax were mixed and kneaded. At this time, the temperature of the kneader was controlled and a first blend was obtained at a discharge temperature of 140 °C to 150 °C. In the second stage kneading, after cooling the first compound to room temperature, 1.75 parts by weight of a rubber accelerator (CZ), 1.5 parts by weight of sulfur powder, and 2.0 parts by weight of a vulcanization accelerator are added to a kneader, and mixed at a temperature of 60° C. or less to 2 A tea blend was obtained. After that, in the third stage kneading, the secondary compound was molded and vulcanized by a vulcanizing press at 160 ° C. for t90 x 1.3 minutes to prepare a rubber specimen.

Example 2

In Example 1, the same method as in Example 1 was used except that a monomer mixture consisting of 51 wt% of 1,3-butadiene, 46 wt% of styrene, and 3 wt% of N-phenylmaleimide was used in preparing the polymer. carried out.

Example 3

In Example 1, the same method as in Example 1 was used except that a monomer mixture consisting of 51 wt% of 1,3-butadiene, 44 wt% of styrene, and 5 wt% of N-phenylmaleimide was used in preparing the polymer. carried out.

Example 4

In Example 3, the preparation of the rubber specimen was carried out in the same manner as in Example 3, except that it was carried out in the following manner.

In one-stage kneading, 90 parts by weight of silica and bis(3-triethoxysilyl as a silane coupling agent) based on 110 parts by weight of the obtained powdered conjugated diene-based copolymer using a Banbari mixer equipped with a temperature control device. propyl) tetrasulfide 7.2 parts by weight, process oil (TDAE) 6 parts by weight, antioxidant (TMDQ) 2.0 parts by weight, antioxidant (6PPD) 2.0 parts by weight, zinc oxide (ZnO) 3.0 parts by weight, stearic acid ( stearic acid) 2.0 parts by weight and 1.0 parts by weight of wax were mixed and kneaded. At this time, the temperature of the kneader was controlled and a first blend was obtained at a discharge temperature of 140 °C to 150 °C. In the second stage kneading, after cooling the first compound to room temperature, 1.75 parts by weight of a rubber accelerator (CZ), 1.5 parts by weight of sulfur powder, and 2.0 parts by weight of a vulcanization accelerator are added to a kneader, and mixed at a temperature of 60 ° C. or less to 2 A tea blend was obtained. After that, in the third stage kneading, the secondary compound was molded and vulcanized by a vulcanizing press at 160 ° C. for t90 x 1.3 minutes to prepare a rubber specimen.

Example 5

In Example 1, the same method as in Example 1 was used, except that a monomer mixture consisting of 51 wt% of 1,3-butadiene, 41 wt% of styrene, and 8 wt% of N-phenylmaleimide was used in preparing the polymer. carried out.

Example 6

In Example 1, the same method as in Example 1 was used except that a monomer mixture consisting of 51 wt% of 1,3-butadiene, 39 wt% of styrene, and 10 wt% of N-phenylmaleimide was used in preparing the polymer. carried out.

comparative example

Comparative Example 1

<Preparation of conjugated diene-based copolymer>

3 parts by weight of sodium dodecylbenzene sulfonate (SDBS) and 0.05 parts by weight of p-methane hydroperoxide based on 100 parts by weight of a monomer mixture consisting of 51% by weight of 1,3-butadiene and 49% by weight of styrene in a nitrogen-substituted polymerization reactor , 0.5 parts by weight of t-dodecyl mercaptan, and 200 parts by weight of ion-exchanged water were mixed to initiate emulsion polymerization at 10°C. Then, when the polymerization conversion reached 60%, the polymerization was stopped to obtain a latex-type conjugated diene-based copolymer.

Then, 37.5 parts by weight of extender oil and 0.5 parts by weight of antioxidant (6PPD) were added to the prepared conjugated diene-based copolymer latex, 1 part by weight of aluminum sulfate was added to 1000 parts by weight of ion-exchanged water, and the temperature was raised to 70 ° C. It was coagulated in water, aged for 20 minutes, and then cooled to obtain a coagulated product, which was washed 2 to 3 times with ion-exchanged water to remove residual monomers, and then dehydrated using a filter. Thereafter, it was dried in an oven at 100° C. for 1 hour to obtain a powdered conjugated diene-based copolymer.

<Preparation of rubber specimen>

The rubber specimen was prepared in the same manner as in Example 1.

Comparative Example 2

In Comparative Example 1, when preparing the conjugated diene-based copolymer, the same as in Comparative Example 1, except that a monomer mixture comprising 51 wt% of 1,3-butadiene, 44 wt% of styrene, and 5 wt% of N-phenylmaleimide was used. It was carried out in the same way.

Comparative Example 3

In Comparative Example 1, when the conjugated diene-based copolymer was prepared, a monomer mixture consisting of 51 wt% of 1,3-butadiene, 46 wt% of styrene, and 3 wt% of 2-hydroxypropyl methacrylate (HPMA) was used, except that was carried out in the same manner as in Comparative Example 1.

Comparative Example 4

In Comparative Example 3, the preparation of the rubber specimen was carried out in the same manner as in Comparative Example 3, except that it was carried out in the following manner.

In one-stage kneading, 90 parts by weight of silica and bis(3-triethoxysilyl as a silane coupling agent) based on 110 parts by weight of the obtained powdered conjugated diene-based copolymer using a Banbari mixer equipped with a temperature control device. propyl) tetrasulfide 7.2 parts by weight, process oil (TDAE) 6 parts by weight, antioxidant (TMDQ) 2.0 parts by weight, antioxidant (6PPD) 2.0 parts by weight, zinc oxide (ZnO) 3.0 parts by weight, stearic acid ( stearic acid) 2.0 parts by weight and 1.0 parts by weight of wax were mixed and kneaded. At this time, the temperature of the kneader was controlled and a first blend was obtained at a discharge temperature of 140 °C to 150 °C. In the second stage kneading, after cooling the first compound to room temperature, 1.75 parts by weight of a rubber accelerator (CZ), 1.5 parts by weight of sulfur powder, and 2.0 parts by weight of a vulcanization accelerator are added to a kneader, and mixed at a temperature of 60° C. or less to 2 A tea blend was obtained. After that, in the third stage kneading, the secondary compound was molded and vulcanized by a vulcanizing press at 160 ° C. for t90 x 1.3 minutes to prepare a rubber specimen.

Comparative Example 5

In Comparative Example 1, the preparation of the rubber specimen was carried out in the same manner as in Comparative Example 1, except that 5 parts by weight of oleylamine was added.

Experimental example

In order to comparatively analyze the physical properties of the rubber compositions prepared in Examples 1 to 6 and Comparative Examples 1 to 5, Mooney viscosity, abrasion resistance, glass transition temperature and viscoelastic properties were measured using the prepared rubber specimens in the following manner, respectively. It was measured and the results are shown in Tables 1 and 2.

* Mooney Viscosity (MV, (ML1+4, @100℃) MU): Using MV-2000 (ALPHA Technologies) at 100℃, Rotor Speed 2±0.02 rpm, Large Rotor to measure the viscosity of the rubber composition At this time, the sample used was left at room temperature (23±3° C.) for more than 30 minutes, and then 27±3 g was collected, filled in the die cavity, and the platen was operated to measure for 4 minutes.

* Abrasion resistance (DIN loss weight): Using a DIN abrasion tester, a load of 10 N is applied to the abrasion resistance of the rubber specimen prepared above, and a load of 10 N is applied to the rubber specimen in a direction perpendicular to the direction of rotation of the drum. After moving to , the amount of wear was measured. The rotational speed of the drum is 40 rpm, and the total travel distance of the specimen at the completion of the test is 40 m.

* Glass transition temperature (Tg, ℃): was measured by a conventional method using DSC.

* Viscoelastic properties: Using Gabo, Germany, DMTS 500N, at a frequency of 10 Hz, Prestrain 5 %, Dynamic Strain 0.5 %, temperature sweep is performed while raising the temperature to 2 ℃ / min within the temperature range of -40 ℃ to 70 ℃ , tanδ were measured, and Compound Tg was expressed from the value of the X-axis of the inflection point in the tanδ graph. The higher the tanδ at 0 °C, which is a low temperature, the better the wet road resistance.

Example One 2 3 4 5 6 copolymer Mooney Viscosity (ML ₁₊₄ 100℃) 52 50 51 51 55 53 Rubber
composition 41 40 42 60 46 44 wear resistance Abrasion (g) 0.111 0.108 0.101 0.120 0.102 0.101 dynamic properties Glass transition temperature (Tg, ℃) -20.8 -20.6 -20 -19.2 -19.6 -19.1 tanδ at 0℃ 0.461 0.462 0.481 0.640 0.483 0.484 tanδ at 60℃ 0.195 0.182 0.172 0.175 0.171 0.172

comparative example One 2 3 4 5 copolymer Mooney viscosity
(ML ₁₊₄ 100℃) 55 54 51 51 53 Rubber
composition 42 42 43.4 59 40 wear resistance Abrasion (g) 0.115 0.115 0.104 0.124 0.108 dynamic properties Glass transition temperature (Tg, ℃) -21.3 -21.3 -19 -18.6 -20.3 tanδ at 0℃ 0.462 0.462 0.526 0.642 0.462 tanδ at 60℃ 0.196 0.198 0.187 0.177 0.197

Referring to Tables 1 and 2, in the case of rubber compositions including the conjugated diene-based copolymers of Examples 1 to 6 prepared according to the present invention, abrasion resistance and viscoelastic properties while maintaining processability at the same or superior level as compared to Comparative Examples This improvement can be confirmed, and in particular, it can be seen that the tanδ value at 60 °C is low, and the rolling resistance characteristics are remarkably improved.

Specifically, in the case of an example containing an amine group in the conjugated diene-based copolymer, it can be seen that the abrasion resistance and rolling resistance properties are improved compared to Comparative Example 1 including the conjugated diene-based copolymer not containing an amine group, and more Specifically, it can be seen that Examples 3, 5, and 6 in which the content of the maleimide-based monomer mixed during the preparation of the conjugated diene-based copolymer is 5% to 10% by weight exhibits better abrasion resistance and rolling resistance properties.

In addition, in the case of Comparative Example 2, in which 5 wt% of N-phenylmaleimide was mixed in the preparation of the conjugated diene-based copolymer, but the deimidization step was not performed, the abrasion resistance and rolling resistance properties were significantly lowered compared to that of Example. that can be checked

In addition, in Comparative Example 3, in which 3 wt% of 2-hydroxypropyl methacrylate monomer having affinity with silica was mixed as a monomer when preparing the conjugated diene-based copolymer, N-phenylmaleimide was used as a monomer in the same content Compared with Example 2 in which the deimidization reaction was performed while including, it was confirmed that the abrasion resistance and rolling resistance properties were lowered.

In addition, even when comparing Example 4 and Comparative Example 4 in which a silica-based filler was used alone as a filler, in the case of Example 4, the abrasion resistance and rolling resistance properties were improved compared to Comparative Example 4 in which a silica-compatible monomer was mixed during the preparation of the copolymer. was able to confirm that

In addition, in the case of Comparative Example 5, in which the amine-based additive was added during the preparation of the rubber composition, because the dispersion of carbon black was facilitated, the abrasion resistance was equivalent to that of Example 1, but the interaction between the conjugated diene-based copolymer and the filler It was confirmed that the effect of improving the rolling resistance characteristics was lowered because it did not affect the operation.

Claims (14)

A conjugated diene-based copolymer comprising a unit derived from a conjugated diene monomer, a unit derived from an aromatic vinyl monomer, and a unit derived from at least one compound selected from the group consisting of compounds represented by the following Chemical Formulas 1 to 4:
[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4,
R ₁ and R ₂ each independently represent N(R ₇ R ₈ ),
R _{3 To} R ₆ Each independently represents N(R ₉ ),
Wherein R _{7 To} R ₉ Each independently represents a hydrogen or an amine group,
* indicates a binding position. According to claim 1,
In Formula 1, _{at least one of R 7} and R ₈ is a conjugated diene-based copolymer representing an amine group. According to claim 1,
In Formula 2, R ₉ is a conjugated diene-based copolymer representing an amine group. According to claim 1,
The content of one or more compound-derived units selected from the group consisting of compounds represented by Chemical Formulas 1 to 4 is 0.1 wt% to 15 wt% based on the total content of the conjugated diene-based copolymer. 5. The method of claim 4,
The content of one or more compound-derived units selected from the group consisting of compounds represented by Chemical Formulas 1 to 4 is 5 to 10% by weight based on the total content of the conjugated diene-based copolymer. According to claim 1,
30% to 80% by weight of the conjugated diene-based monomer-derived unit, 20% to 60% by weight of the aromatic vinyl-based monomer-derived unit, and at least one compound-derived unit selected from the group consisting of compounds represented by Formulas 1 to 4 Conjugated diene-based copolymer comprising 15% by weight to 15% by weight. preparing a polymer by emulsion polymerization of a conjugated diene-based monomer, an aromatic vinyl-based monomer, and a maleimide-based monomer; and
A method for producing a conjugated diene-based copolymer comprising the step of deimidizing the polymer. 8. The method of claim 7,
The maleimide-based monomer is maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N- Toluylmaleimide, N-xysilylmaleimide, N-naphthylmaleimide, Nt-butylmaleimide, N-orsochlorphenylmaleimide, N-orsomethoxyphenylmaleimide and N-orsobromophenylmaleimide A method for producing a conjugated diene-based copolymer comprising at least one selected from the group consisting of 8. The method of claim 7,
The step of deimidizing the polymer is a method for producing a conjugated diene-based copolymer that is carried out including a reducing agent and an acid. 10. The method of claim 9,
The reducing agent is a method for producing a conjugated diene-based copolymer comprising at least one selected from the group consisting of hydrazine and hydrazine hydrate. 10. The method of claim 9,
The acid is a method for producing a conjugated diene-based copolymer comprising at least one selected from the group consisting of hydrochloric acid, nitric acid and sulfuric acid. 10. The method of claim 9,
In the step of deimidizing the polymer, 1 part by weight to 30 parts by weight of a reducing agent and 0.1 parts by weight to 10 parts by weight of an acid are added based on solid content based on 100 parts by weight of the total of the polymer. Method for producing a conjugated diene-based copolymer . A rubber composition comprising the conjugated diene-based copolymer according to claim 1 and a filler. 14. The method of claim 13,
The rubber composition comprising at least one selected from the group consisting of a carbon black filler and a silica-based filler.