KR102037842B1

KR102037842B1 - Alkoxysillane modifying agent comprising tertiary amino group and preparation method of modified conjugated diene polymer using the same

Info

Publication number: KR102037842B1
Application number: KR1020160030299A
Authority: KR
Inventors: 이호영; 김노마; 김유진; 문민식
Original assignee: 주식회사 엘지화학
Priority date: 2016-03-14
Filing date: 2016-03-14
Publication date: 2019-10-30
Also published as: KR20170106770A

Abstract

In the present invention, the alkoxysilane-based modifier of formula (1) comprising at least three tertiary amino groups, which can easily introduce a filler affinity functional group into the conjugated diene-based polymer chain, a modification comprising a functional group derived from the alkoxysilane-based modifier Provided are a conjugated diene-based polymer, a method for producing the modified conjugated diene-based polymer, a rubber composition comprising the modified conjugated diene-based polymer, and molded articles and tires prepared from the rubber composition:
[Formula 1]

In Formula 1, R ¹ to R ⁷ , and p are as defined in the specification.

Description

Alkoxysillane modifying agent comprising tertiary amino group and preparation method of modified conjugated diene polymer using the same}

The present invention provides an alkoxysilane-based modifier comprising at least three tertiary amino groups in a molecule, a modified conjugated diene-based polymer comprising a functional group derived from the alkoxysilane-based modifier, a method for producing the modified conjugated diene-based polymer, and the modified conjugated diene system A rubber composition comprising a polymer.

In recent years, with the demand for low fuel consumption for automobiles, there has been a demand for conjugated diene-based polymers having low rolling resistance, excellent wear resistance and tensile properties, and adjusting stability represented by wet skid resistance.

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, a repulsive elasticity of 50 ° C. to 80 ° C., tan δ, Goodrich heating and the like are used. That is, a rubber material having a high rebound elasticity at the above temperature or a small tan δ or good rich heat generation is preferable.

As a rubber material having a low hysteresis loss, natural rubber, polyisoprene rubber, polybutadiene rubber and the like are known, but these have a problem of low wet skid resistance. Recently, conjugated diene-based (co) polymers such as styrene-butadiene rubber (hereinafter referred to as SBR) or butadiene rubber (hereinafter referred to as BR) have been produced by emulsion polymerization or solution polymerization and used as rubber for tires. . Among them, the greatest advantage of solution polymerization over emulsion polymerization is that the vinyl structure content and styrene content that define rubber properties can be arbitrarily controlled, and molecular weight and physical properties can be adjusted by coupling or modification. It can be adjusted. Therefore, it is easy to change the structure of the final manufactured SBR or BR rubber, and the movement of the chain ends can be reduced by the binding or modification of the chain ends, and the bonding strength with fillers such as silica or carbon black can be increased. It is widely used as a rubber material for tires.

When the solution-polymerized SBR is used as a rubber material for tires, the vinyl content in the SBR is increased to increase the glass transition temperature of the rubber, thereby controlling tire required properties such as running resistance and braking force, and properly adjusting the glass transition temperature. By adjusting the fuel consumption can be reduced.

The solution polymerization SBR is prepared using an anionic polymerization initiator, and is used by binding or modifying the chain ends of the formed polymer using various modifiers.

For example, US Pat. No. 4,397,994 discloses a technique in which the active anion at the chain end of a polymer obtained by polymerizing styrene-butadiene in a nonpolar solvent using alkyllithium, a monofunctional initiator, using a binder such as a tin compound. It was.

Meanwhile, carbon black and silica are used as reinforcing fillers for tire treads. When silica is used as reinforcing fillers, low hysteresis loss and wet skid resistance are improved. However, the hydrophilic surface silica has a disadvantage of poor dispersibility due to low affinity with rubber compared to the hydrophobic surface carbon black, so that a separate silane coupler may be used to improve dispersibility or to impart a bond between silica and rubber. It is necessary to use a ring agent.

Thus, a method of introducing a functional group having affinity or reactivity with silica to the rubber molecule terminal portion, but the effect is not sufficient.

Therefore, there is a need for development of a rubber having high affinity with fillers including silica.

US 4,397,994 A

The present invention has been made to solve the problems of the prior art, and an object thereof is to provide an alkoxysilane-based modifier comprising at least three tertiary amino groups in the molecule.

It is another object of the present invention to provide a modified conjugated diene-based polymer having excellent affinity for a filler in a rubber composition, including the alkoxysilane-based modifier-derived functional group.

Still another object of the present invention is to provide a method for producing the modified conjugated diene polymer using the alkoxysilane-based modifier.

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

In order to solve the above problems, according to an embodiment of the present invention provides an alkoxysilane-based modifier represented by the following formula (1):

[Formula 1]

In Chemical Formula 1,

R ¹ to R ⁵ are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms or a functional group represented by the following Chemical Formula 2, provided that at least one of R ¹ to R ⁵ is a functional group represented by the following Chemical Formula 2,

R ⁶ and R ⁷ are each independently a divalent hydrocarbon group having 1 to 10 carbon atoms, and

p is an integer from 1 to 20,

[Formula 2]

In Chemical Formula 2,

R ⁸ is a divalent hydrocarbon group having 1 to 10 carbon atoms,

A ¹ to A ³ are each independently selected from the group consisting of an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms and a halogen group, provided that at least one of A ¹ to A ³ is alkoxy having 1 to 6 carbon atoms Qi.

In addition, according to another embodiment of the present invention provides a modified conjugated diene-based polymer comprising a functional group derived from the alkoxysilane-based modifier represented by the formula (1).

According to another embodiment of the present invention, a step of polymerizing a conjugated diene-based monomer or an aromatic vinyl monomer and a conjugated diene-based monomer in the presence of an organoalkali metal compound in a hydrocarbon solvent to prepare an active polymer combined with alkali metal; And it provides a method for producing the modified conjugated diene-based polymer comprising the step of reacting the active polymer with the alkoxysilane-based compound represented by the formula (1).

In addition, according to another embodiment of the present invention, there is provided a rubber composition comprising the modified conjugated diene-based polymer.

The alkoxysilane-based modifier represented by Formula 1 according to the present invention includes at least three tertiary amino groups in the molecule, and when used as a modifier of the conjugated diene-based polymer, exhibits excellent affinity for the filler in the conjugated diene-based polymer chain. Functional groups such as tertiary amino groups can be provided.

The modified conjugated diene-based polymer according to the present invention may include a functional group derived from an alkoxysilane-based modifier of Formula 1, such as a tertiary amino group, thereby exhibiting excellent affinity for fillers, particularly silica fillers, in the preparation of rubber compositions. have.

In addition, in the production method according to the present invention, by using the alkoxysilane-based modifier of the formula (1), it is possible to easily introduce functional functional groups, such as tertiary amino groups, having excellent affinity for the filler in the conjugated diene-based polymer.

In addition, the rubber composition according to the present invention may include a modified conjugated diene-based polymer having excellent affinity with the filler, thereby preventing the aggregation of the filler in the rubber composition and increasing the dispersibility of the filler, thereby improving the processability of the rubber composition. As a result, the physical properties of the molded article manufactured using the rubber composition can be improved, and in particular, the tensile strength, abrasion resistance, rolling resistance, wet road resistance, and low running resistance in the tire can be improved.

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

The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

According to one embodiment of the present invention, by including at least three tertiary amino groups in a molecule, the conjugated diene-based polymer is easily introduced into the tertiary amino group, which is a filler affinity functional group, and is subsequently modified. Provided is a modifier comprising an alkoxysilane-based compound of Formula 1, which can improve the dispersibility of the filler in the rubber composition to improve the processability of the rubber composition:

[Formula 1]

In Chemical Formula 1,

p is an integer from 1 to 20,

[Formula 2]

In Chemical Formula 2,

R ⁸ is a divalent hydrocarbon group having 1 to 10 carbon atoms,

In the present invention, the term "at least" refers to a minimum, and may mean, for example, "from to". That is, at least three may represent at least three or three or more.

Specifically, in Formula 1, R ¹ to R ⁵ each independently represent an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, or a propyl group; Alkenyl groups having 2 to 10 carbon atoms; An alkynyl group having 2 to 10 carbon atoms; Cycloalkyl groups having 3 to 10 carbon atoms such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, or a cyclohexyl group; C6-C10 aryl groups, such as a phenyl group; C7-C10 alkylaryl groups, such as 4-methylphenyl group; Arylalkyl groups having 7 to 10 carbon atoms such as benzyl group; And it may be selected from the group consisting of functional groups of the formula (2), provided that at least one of R ¹ to R ⁵ is a functional group of the formula (2). More specifically, the R ¹ to R ⁵ each independently may be an action of 1 to 10 carbon atoms or an alkyl group of the general formula (2), at least one of R ¹ to R ⁵ is an end functional group of the general formula (2).

In addition, when any one of R ¹ to R ⁵ is a functional group of the formula (2), in the formula (2), R ⁸ is specifically a linear or branched alkylene group having 2 to 8 carbon atoms, more specifically It may be a linear alkylene group having 3 to 6 carbon atoms, such as a propylene group, butylene group or hexylene group.

In addition, specifically, in Formula 2, A ¹ to A ³ each independently represent an alkoxy group having 1 to 6 carbon atoms such as a methoxy group, an ethoxy group, or a propoxy group; Alkyl groups having 1 to 6 carbon atoms such as a methyl group, an ethyl group, or a propyl group; And it may be selected from the group consisting of a halogen group, such as fluoro, chloro or bromo, provided that at least one of A ¹ to A ³ is an alkoxy group having 1 to 6 carbon atoms. More specifically, in Formula 2, A ¹ to A ³ may be each independently a halogen group or an alkoxy group having 1 to 4 carbon atoms, provided that at least one of A ¹ to A ³ is an alkoxy group having 1 to 4 carbon atoms.

In addition, in Formula 1, R ⁶ and R ⁷ are each independently a linear or branched alkylene group having 2 to 8 carbon atoms, and more specifically, a straight chain having 3 to 6 carbon atoms such as a propylene group, butylene group or hexylene group. It may be an alkylene group.

Further, in Chemical Formula 1, p may be an integer of 1 to 10 specifically, more specifically, an integer of 2 to 10, even more specifically an integer of 2 to 5.

More specifically, the modifier including the alkoxysilane-based compound represented by Formula 1 according to an embodiment of the present invention, in Formula 1, R ¹ to R ⁴ are each independently an alkyl group having 1 to 10 carbon atoms or the A functional group of formula (2), R ⁵ is a functional group of formula (2), R ⁶ and R ⁷ are each independently a linear or branched alkylene group having 2 to 8 carbon atoms, and p is a compound having an integer of 1 to 10 In the above Formula 2, R ⁸ is a linear or branched alkylene group having 2 to 8 carbon atoms, A ¹ to A ³ are each independently alkoxy group having 1 to 6 carbon atoms, alkyl group having 1 to 6 carbon atoms And it is selected from the group consisting of halogen, provided that at least one of A ¹ to A ³ may be an alkoxy group having 1 to 6 carbon atoms.

More specifically, the modifier including the alkoxysilane-based compound represented by Formula 1 according to an embodiment of the present invention, in Formula 1, R ¹ to R ⁴ are each independently an alkyl group having 1 to 10 carbon atoms, or an alkyl group having 1 to 4, R ⁵ is a functional group of formula 2, R ⁶ and R ⁷ are each independently a C 3 -C 6 straight chain alkylene group, and p include integers compound of 2 to 5 In this case, in Formula 2 R ⁸ is a straight alkylene group having 3 to 6 carbon atoms, A ¹ to A ³ may be each independently alkoxy group having 1 to 4 carbon atoms.

More specifically, the alkoxysilane-based compound represented by Formula 1 according to an embodiment of the present invention may be a compound of Formula 3 or 4 below, any one or a mixture of two may be used as a modifier.

[Formula 3]

[Formula 4]

The alkoxysilane-based modifying agent represented by Formula 1 according to an embodiment of the present invention may be a modifying agent for modifying the structure, properties, and physical properties of the rubber, in particular conjugated diene such as butadiene-based polymer or styrene-butadiene copolymer It can be used easily as a modifier of the polymer.

Specifically, the modifier including the alkoxysilane-based compound represented by Formula 1 according to an embodiment of the present invention, when used as a modifier of the conjugated diene-based polymer, will be bonded in the form of a tertiary amino group to the conjugated diene-based polymer. At this time, the modified conjugated diene-based polymer has a structure containing a plurality of tertiary amino groups in the molecule, it can exhibit a better affinity for the filler in the rubber composition, in particular silica-based filler, and prevents the aggregation of the filler in the rubber composition Dispersibility can be improved. As a result, the processability of the rubber composition comprising the modified conjugated diene-based polymer can be improved, and the physical properties of the finally obtained molded article, in particular, the tensile strength, wear resistance, rolling resistance, wet road resistance and low running resistance of the tire can be improved. have.

Accordingly, according to another embodiment of the present invention provides a modified conjugated diene-based polymer modified by a modifier comprising the alkoxysilane-based compound of Formula 1.

Specifically, the modified conjugated diene-based polymer may include a functional group derived from an alkoxysilane-based compound of Formula 1, such as a tertiary amino group. More specifically, one or more tertiary amino groups may be bonded to the conjugated diene polymer chain.

In addition, the conjugated diene polymer may be a homopolymer of a conjugated diene monomer or a copolymer of a conjugated diene monomer and an aromatic vinyl monomer.

In addition, when the modified conjugated diene polymer is a copolymer, the copolymer is a random copolymer in which structural units constituting the copolymer are randomly arranged and bonded, including a structural unit derived from a conjugated diene monomer and a structural unit derived from an aromatic vinyl monomer. It may be.

Specifically, the modified conjugated diene-based polymer may have a narrow molecular weight distribution (Mw / Mn) of 1.1 to 5.0. If the molecular weight distribution of the modified conjugated diene-based polymer is more than 5.0 or less than 1.1, there is a fear that the tensile properties and viscoelasticity when the rubber composition is applied. In consideration of the remarkable effect of the tensile properties and viscoelasticity improving effect of the polymer according to the molecular weight distribution control, the molecular weight distribution of the modified conjugated diene-based polymer may be specifically 1.3 to 3.0.

In the present invention, the molecular weight distribution of the modified butadiene-based polymer can be calculated from the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn). In this case, the number average molecular weight (Mn) is a common average of individual polymer molecular weights obtained by measuring the molecular weights of n polymer molecules, calculating the sum of these molecular weights, and dividing by n, and the straight chain (Mw) is a polymer composition. The molecular weight distribution of is shown. All molecular weight averages can be expressed in grams per mole (g / mol).

In addition, in this invention, the said weight average molecular weight and number average molecular weight are polystyrene conversion molecular weights analyzed by gel permeation chromatography (GPC), respectively.

In addition, the modified conjugated diene-based polymer may satisfy the above molecular weight distribution conditions and may have a number average molecular weight (Mn) of 50,000 g / mol to 2,000,000 g / mol, more specifically 200,000 g / mol to 1,000,000 g / mol. The modified conjugated diene-based polymer may have a weight average molecular weight (Mw) of 100,000 g / mol to 4,000,000 g / mol, and more specifically, 300,000 g / mol to 1,500,000 g / mol.

When the modified conjugated diene-based polymer has a straight chain (Mw) of less than 100,000 g / molg / mol or a number average molecular weight (Mn) of less than 50,000 g / mol, there is a fear of deterioration of tensile properties when applied to a rubber composition. In addition, when the linear (Mw) exceeds 4,000,000 g / mol or the number average molecular weight (Mn) exceeds 2,000,000 g / mol, the workability of the rubber composition is deteriorated due to the decrease in processability of the modified conjugated diene-based polymer, Dough becomes difficult, and it may be difficult to sufficiently improve the physical properties of the rubber composition.

More specifically, when the modified conjugated diene-based polymer according to an embodiment of the present invention simultaneously meets the weight average molecular weight (Mw) and the number average molecular weight conditions together with the above molecular weight distribution, the rubber composition when applied to the rubber composition It is possible to improve the balance without biasing the tensile properties, viscoelasticity and workability.

In addition, the modified conjugated diene-based polymer may have a vinyl content of 5% by weight or more, specifically 10% by weight or more, more specifically 10% by weight to 50% by weight, and the glass transition temperature when the vinyl content is in the above range. Can be adjusted to an appropriate range, and when applied to a tire, not only the properties required for the tire such as driving resistance and braking force are excellent, but also it has an effect of reducing fuel consumption.

In this case, the vinyl content represents the content of the 1,2-added conjugated diene monomer instead of 1,4-addition with respect to the total weight of the conjugated diene polymer composed of a monomer having a vinyl group or a conjugated diene monomer.

In addition, the modified conjugated diene-based polymer according to an embodiment of the present invention may have a Mooney viscosity (MV) of 40 to 60, specifically 40 to 50 at 100 ℃. When it has the Mooney viscosity of the above-mentioned range, it can exhibit more excellent workability.

In the present invention, the Mooney viscosity may be measured using a Mooney viscometer, for example, Rotor Speed 2 ± 0.02rpm, Large Rotor at 100 with a Monsanto MV2000E. At this time, the sample used can be measured by leaving the plate at 27 ± 3g after leaving at room temperature (23 ± 3) for more than 30 minutes and operating the platen.

According to another embodiment of the present invention, there is provided a method for producing the modified conjugated diene-based polymer using a modifier containing an alkoxysilane-based compound represented by the formula (1).

The preparation method specifically comprises the step of polymerizing a conjugated diene monomer or an aromatic vinyl monomer and a conjugated diene monomer in the presence of an organic alkali metal compound in a hydrocarbon solvent to prepare an active polymer having an alkali metal bonded to at least one end thereof (step One); And reacting the active polymer with an alkoxysilane-based modifier represented by Formula 1 (step 2).

Step 1 is a step for preparing an active polymer having an alkali metal bonded to at least one end, and is carried out by polymerizing a conjugated diene monomer, or an aromatic vinyl monomer and a conjugated diene monomer in the presence of an organic alkali metal compound in a hydrocarbon solvent. can do.

The polymerization of step 1 may be to use a conjugated diene monomer alone or a conjugated diene monomer and an aromatic vinyl monomer together as a monomer. That is, the polymer prepared by the above production method according to an embodiment of the present invention may be a conjugated diene monomer homopolymer or a copolymer derived from a conjugated diene monomer and an aromatic vinyl monomer.

The conjugated diene monomer is not particularly limited, but for example, 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-1,3-octadiene, isoprene and 2-phenyl It may be one or more selected from the group consisting of -1,3-butadiene.

When the conjugated diene monomer and the aromatic vinyl monomer are used together as the monomer, the conjugated diene monomer may include 60% by weight or more of the unit derived from the conjugated diene monomer in the finally prepared modified conjugated diene polymer. 60 wt% to 90 wt%, more specifically, 60 wt% to 85 wt%.

The aromatic vinyl monomer is not particularly limited, but for example, styrene, α-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4- (p It may be one or more selected from the group consisting of -methylphenyl) styrene and 1-vinyl-5-hexylnaphthalene.

When the conjugated diene monomer and the aromatic vinyl monomer are used together as the monomer, the aromatic vinyl monomer may be 40 wt% or less of the aromatic vinyl monomer-derived unit in the finally prepared modified conjugated diene polymer. It may be used in an amount comprised from 10% by weight to 40% by weight, more specifically 15% by weight to 40% by weight.

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

The organoalkali metal compound may be used in an amount of 0.1 mmol to 1.0 mmol based on 100 g of the total monomer weight.

The organoalkali metal compound is not particularly limited, but for example, methyllithium, ethyllithium, propyllithium, n-butyllithium, s-butyllithium, t-butyllithium, hexyllithium, n-decyllithium, t-octylithium, Phenyllithium, 1-naphthyllithium, n-eicosilium, 4-butylphenyllithium, 4-tolyllithium, cyclohexyllithium, 3,5-di-n-heptylcyclohexyllithium, 4-cyclopentyllithium, naph At least one member selected from the group consisting of sodium sodium, naphthyl potassium, lithium alkoxide, sodium alkoxide, potassium alkoxide, lithium sulfonate, sodium sulfonate, potassium sulfonate, lithium amide, sodium amide, potassium amide and lithium isopropylamide. Can be.

The polymerization of step 1 may be performed by further adding a polar additive as needed, the polar additive may be added to 0.001 parts by weight to 1.0 parts by weight based on 100 parts by weight of the total monomer. Specifically, the amount may be added in an amount of 0.005 parts by weight to 0.5 parts by weight, and more specifically 0.01 parts by weight to 0.3 parts by weight based on 100 parts by weight of the total monomers.

The polar additives include tetrahydrofuran, ditetrahydrofurylpropane, diethyl ether, cycloamal ether, dipropyl ether, ethylene dimethyl ether, ethylene dimethyl ether, diethyl glycol, dimethyl ether, tertiary butoxyethoxyethane, bis It may be one or more selected from the group consisting of (3-dimethylaminoethyl) ether, (dimethylaminoethyl) ethyl ether, trimethylamine, triethylamine, tripropylamine and tetramethylethylenediamine.

In the manufacturing method according to an embodiment of the present invention, when the conjugated diene-based monomer and the aromatic vinyl-based monomer are copolymerized by using the polar additive, the reaction rate can be easily compensated for by forming a random copolymer. Can be induced.

The polymerization of step 1 may be carried out through adiabatic polymerization, or isothermal polymerization.

Here, adiabatic polymerization refers to a polymerization method including a step of polymerizing with self-heating reaction without adding heat after the addition of the organoalkali metal compound, and the isothermal polymerization is an arbitrary heat after adding the organoalkali metal compound. It represents a polymerization method for maintaining a constant temperature of the polymer by adding or taking away heat.

The polymerization may be performed at a temperature range of -20 ° C to 200 ° C, specifically 0 ° C to 150 ° C, and more specifically 10 ° C to 120 ° C.

Step 2 is a modification reaction step of reacting the active polymer with the alkoxysilane-based modifier represented by Formula 1 to prepare a modified conjugated diene-based polymer.

In this case, the modifier for rubber represented by Chemical Formula 1 may be as described above. The modifying agent for rubber represented by Formula 1 may be used in a ratio of 0.05 mol to 3.0 mol relative to 1 mol of the organic alkali metal compound.

In addition, the reaction of step 2 is a modification reaction for introducing a functional group into the polymer, each reaction may be performed for 1 minute to 5 hours in the temperature range of 0 ℃ to 90 ℃.

The preparation method according to an embodiment of the present invention may further include one or more steps of recovering and drying the solvent and the unreacted monomer, if necessary after step 2 above.

In addition, according to another embodiment of the present invention provides a rubber composition comprising the modified conjugated diene-based polymer.

The rubber composition may include a modified conjugated diene-based polymer of 0.1 wt% or more and 100 wt% or less, specifically 10 wt% to 100 wt%, 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, improvement effects such as 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 components may be included in an amount of 90% by weight or less based on the total weight of the rubber composition. Specifically, the modified conjugated diene copolymer may be included in an amount of 1 part by weight to 900 parts by weight based on 100 parts by weight.

The rubber component may be natural rubber or synthetic rubber, for example, the rubber component may 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 obtained by modifying or refining 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., and any one or a mixture of two or more thereof may be used. have.

In addition, the rubber composition may include 0.1 part by weight to 150 parts by weight of a filler based on 100 parts by weight of the modified conjugated diene-based polymer.

Specifically, the filler may be a silica-based filler or a carbon black-based filler, and any one or a mixture thereof may be used.

More specifically, the filler may be silica, and more specifically, it may be wet silica (silicate silicate), dry silica (silicate anhydrous), calcium silicate, aluminum silicate or colloidal silica. More specifically, the filler may be a wet silica having the most remarkable effect of improving the breaking characteristics and wet grip (wet grip).

Meanwhile, when the silica-based filler is used as the filler, a silane coupling agent may be used together to improve reinforcement and low heat generation.

Specific examples of the silane coupling agent include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane , 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasul Feed, 3-triethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilyl Propylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzolyl tetrasulfide, 3-triethoxysilylpropyl methacrylate Monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide 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-trimethoxysilylpropylbenzothiazyl tetrasulfide.

In addition, in the rubber composition according to one embodiment of the present invention, a modified conjugated diene-based polymer having a functional group having a high affinity with a silica-based filler as an active moiety is used as the rubber component. The compounding amount can be reduced than usual. Specifically, the silane coupling agent may be used in an amount of 1 to 20 parts by weight based on 100 parts by weight of the silica-based filler. When used in the above range, the gelation of the rubber component can be prevented while the effect as a coupling agent is sufficiently exhibited. More specifically, the silane coupling agent may be used in 5 parts by weight to 15 parts by weight based on 100 parts by weight of silica.

In addition, the rubber composition according to an embodiment of the present invention may be sulfur crosslinkable, 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 parts by weight to 10 parts by weight based on 100 parts by weight of the rubber component. When included in the content range, it is possible to ensure the required elastic modulus and strength of the vulcanized rubber composition, and at the same time obtain a low fuel consumption.

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, in particular, vulcanization accelerators, process oils, plasticizers, anti-aging agents, anti-scoring agents, zinc white (zinc white) ), Stearic acid, a thermosetting resin, or a thermoplastic resin may be further included.

The said vulcanization accelerator is not specifically limited, Specifically, M (2-mercapto benzothiazole), DM (dibenzothiazyl disulfide), CZ (N-cyclohexyl-2- benzothiazyl sulfenamide), etc. Thiazole compounds, or guanidine compounds such as DPG (diphenylguanidine) can be used. The vulcanization accelerator may be included in an amount of 0.1 parts by weight 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, may be a paraffinic, naphthenic, or aromatic compound, and more specifically, aromatic process oil, hysteresis loss in consideration of tensile strength and wear resistance. And naphthenic or paraffinic process oils may be used when considering low temperature properties. The process oil may be included in an amount of 100 parts by weight or less with respect to 100 parts by weight of the rubber component, when included in the content, it is possible to prevent the degradation of tensile strength, low heat generation (low fuel consumption) of the vulcanized rubber.

In addition, as the anti-aging agent, specifically N-isopropyl-N'-phenyl-p-phenylenediamine, N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine, 6- Methoxy-2,2,4-trimethyl-1,2-dihydroquinoline, or a high temperature condensate of diphenylamine and acetone. The anti-aging agent may be used in an amount of 0.1 parts by weight 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 kneading machine such as a Banbury mixer, a roll, an internal mixer, etc. by the above formulation, and also has low heat resistance and abrasion resistance by a vulcanization process after molding. This excellent rubber composition can be obtained.

Accordingly, the rubber composition may be used for tire members such as tire treads, under treads, sidewalls, carcass coated rubbers, belt coated rubbers, bead fillers, pancreapers, or bead coated rubbers, dustproof rubbers, belt conveyors, hoses, and the like. It may be useful for the production of various industrial rubber products.

In addition, according to another embodiment of the present invention, there is provided a molded article and a tire manufactured using the rubber composition.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. However, the following Examples and Experimental Examples are provided to illustrate the present invention, and the scope of the present invention is not limited only to these examples.

Example 1

Into a 20 L autoclave reactor, 270 g of styrene, 710 g of 1,3-butadiene, 5000 g of normal hexane, and 1.3 g of 2,2-bis (2-oxoranyl) propane were added as a polar additive, and the temperature inside the reactor was 40 ° C. Adjusted to. When the internal temperature of the reactor reached 40 ° C, 4 mmol of n-butyllithium was added to the reactor to perform an adiabatic heating reaction. After 20 minutes of reaction, 20 g of 1,3-butadiene was added thereto, and the end of the SSBR was capped with butadiene. After 5 minutes, 4 mmol of the modifying agent of Chemical Formula 3 was added and reacted for 15 minutes. Then, the polymerization reaction was stopped using ethanol, and 5 ml of a solution in which 0.3 wt% of BHT (butylated hydroxytoluene), an antioxidant, was dissolved in hexane was added. The resulting polymer was placed in hot water heated with steam, stirred to remove the solvent, and then dried in rolls to remove residual solvent and water to prepare a modified styrene-butadiene copolymer.

(3)

Example 2

A modified styrene-butadiene copolymer was prepared in the same manner as in Example 1 except that the modification reaction was performed by adding 4 mmol of the modifying agent of Formula 4 instead of the modifying agent of Formula 3.

(4)

Comparative Example 1

A modified styrene-butadiene copolymer was prepared in the same manner as in Example 1, except that 4 mmol of tetraethoxysilane (TEOS) was added instead of the denaturing agent of Chemical Formula 3 to perform a modification reaction.

Experimental Example 1

The weight average molecular weight (Mw), the number average molecular weight (Mn), the polydispersity index (PDI), the component analysis and the pattern viscosity (MV) for each of the modified styrene-butadiene copolymers of Examples 1, 2 and Comparative Example 1, respectively Were respectively measured. The results are shown in Table 1 below.

1) Component Analysis

Styrene derived units (SM) and vinyl content in each copolymer were measured using NMR.

2) Molecular Weight Analysis

The weight average molecular weight (Mw) and the number average molecular weight (Mn) of each copolymer were measured by gel permeation chromatograph (GPC) analysis under 40 ° C. At this time, the column (column) was used in combination with two bags of PLgel Olexis of Polymer Laboratories Co., Ltd. and one PLgel mixed-C column, all of the newly replaced column was a mixed bed column. In addition, PS (polystyrene) was used as the GPC standard material in the molecular weight calculation. The polydispersity index (PDI) was calculated as the ratio (Mw / Mn) of the weight average molecular weight and the number average molecular weight measured by the above method.

3) Mooney viscosity analysis

The Mooney viscosity of each copolymer was measured by MV-2000 (Alpha Technologies Co., Ltd.) for 15 minutes or more of each sample weight 15g or more for 1 minute and then at 100 ℃ for 4 minutes.

Example 1 Example 2 Comparative Example 1 n-butyllithium usage
(Mmol based on 100 g total monomer) 0.4 0.4 0.4 Denaturant usage
(Based on 100 g of monomer total weight) 0.4 0.4 0.4 Mooney viscosity (MV) 44 50 64 NMR Styrene content
(% By weight of polymer total weight) 26.8 27.0 27.3 Vinyl content
(% By weight of polymer total weight) 43.3 43.1 42.7 GPC Mn (× 10 ⁵ g / mol) 12.8 14.3 16.8 Mw (× 10 ⁵ g / mol) 14.8 20.2 22.6 PDI (Mw / Mn) 1.16 1.41 1.34

Experimental Example 2

In order to compare and analyze the physical properties of the rubber composition and the molded article prepared from each of the modified styrene-butadiene copolymers of Examples 1, 2 and Comparative Example 1, the tensile and viscoelastic properties were measured.

1) Preparation of Rubber Composition

Each rubber composition was prepared through a first stage kneading, a second stage kneading and a third stage kneading. In this case, the amount of the material except for the modified styrene-butadiene copolymer is shown based on 100 parts by weight of the modified styrene-butadiene copolymer. In the first stage kneading, 100 parts by weight of each copolymer, 70 parts by weight of silica, bis (3-triethoxysilylpropyl) tetrasulfate as a silane coupling agent using a half-variety mixer equipped with a temperature control device at 80 rpm. 11.02 parts by weight of feed, 33.75 parts by weight of process oil (TDAE), 2.0 parts by weight of antioxidant (TMDQ), 2.0 parts by weight of antioxidant, 3.0 parts by weight of zinc oxide (ZnO), 2.0 parts by weight of stearic acid, and 1.0 weight part of waxes were blended and kneaded. At this time, the temperature of the kneader was controlled and the primary blend was obtained at the discharge temperature of 140 ° C to 150 ° C. In the second stage kneading, after cooling the primary blend 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 vulcanization accelerator are added to the kneader, and the mixture is mixed at a temperature of 60 ° C. or lower to mix the secondary mixture. Got. Thereafter, the second blend was molded in a third stage kneading, and vulcanized by vulcanization press at 180 to 90 minutes for each vulcanized rubber.

2) tensile properties

Tensile characteristics were prepared in accordance with the tensile test method of ASTM 412 (thickness 25 mm, length 80 mm) and measured the tensile strength at the time of cutting the specimen and the tensile stress (300% modulus) at 300% elongation. Specifically, tensile properties were measured at a rate of 50 cm / min at room temperature using a Universal Test Machin 4204 (Instron Co., Ltd.) tensile tester to obtain tensile strength and tensile stress at 300% elongation.

3) viscoelastic properties

Viscoelastic properties were measured by using a dynamic mechanical analyzer (TA Co., Ltd.) in a torsion mode by changing the strain at a frequency of 10 Hz and measuring temperature (0 ° C. to 60 ° C.). The Payne effect (ΔG ′) is expressed as the difference between the minimum and maximum values at 0.28% to 40% of the strain. The smaller the Payne effect, the better the dispersibility of the filler. In addition, the lower the high temperature 60 ° C Tan δ, the less the hysteresis loss and the better the low cloud resistance (fuel efficiency).

Example 1 Example 2 Comparative Example 1 300% Modulus (Kgf / cm ² ) 147 153 122 Tensile strength (Kgf / cm ²⁾ 220 217 172 △ G ' 0.32 0.77 1.33 tanδ @ 0 ℃ 1.167 1.084 0.972 tanδ @ 60 ℃ 0.083 0.088 0.132

As a result of the experiment, the rubber composition comprising the modified styrene-butadiene polymer of Example 1 or 2 modified using the modifying agent according to the present invention was superior in both tensile strength, viscoelasticity and processability compared to Comparative Example 1.

Claims

Alkoxysilane-based modifiers represented by Formula 1 below:
[Formula 1]

In Chemical Formula 1,
R ¹ to R ⁴ are each independently an alkyl group having 1 to 4 carbon atoms,
R ⁵ is a functional group represented by Formula 2,
R ⁶ and R ⁷ are each independently a C 3 -C 6 straight chain alkylene group, and
p is an integer from 2 to 5,
[Formula 2]

In Chemical Formula 2,
R ⁸ is a straight alkylene group having 3 to 6 carbon atoms,
A ¹ to A ³ are each independently an alkoxy group having 1 to 4 carbon atoms.

delete

The method according to claim 1,
The alkoxysilane-based modifier is an alkoxysilane-based modifier comprising a compound of the formula
[Formula 3]

The method according to claim 1,
An alkoxysilane modifier, which is a modifier for conjugated diene polymer modification.

The method according to claim 5,
The conjugated diene polymer is an alkoxysilane-based modifier is a conjugated diene monomer homopolymer or a copolymer of a conjugated diene monomer and an aromatic vinyl monomer.

Modified conjugated diene-based polymer comprising a functional group derived from an alkoxysilane-based modifier represented by the general formula (1):
[Formula 1]

In Chemical Formula 1,
R ¹ to R ⁴ are each independently an alkyl group having 1 to 4 carbon atoms,
R ⁵ is a functional group represented by Formula 2,
R ⁶ and R ⁷ are each independently a linear alkylene group having 3 to 6 carbon atoms, and
p is an integer from 2 to 5,
[Formula 2]

The method according to claim 7,
A modified conjugated diene-based polymer having a number average molecular weight of 50,000 g / mol to 2,000,000 g / mol and a weight average molecular weight of 100,000 g / mol to 4,000,000 g / mol.

The method according to claim 7,
Modified conjugated diene-based polymer having a molecular weight distribution of 1.1 to 5.0.

The method according to claim 7,
The modified conjugated diene-based polymer is a modified conjugated diene-based polymer having a Mooney viscosity at 100 ℃ 40 to 60.

In a hydrocarbon solvent, polymerizing a conjugated diene monomer, or an aromatic vinyl monomer and a conjugated diene monomer in the presence of an organoalkali metal compound to prepare an active polymer having an alkali metal bound thereto; And
Method for producing a modified conjugated diene-based polymer according to claim 7, comprising the step of reacting the active polymer with an alkoxysilane-based modifier represented by the formula (1):
[Formula 1]

The method according to claim 11,
The organoalkali metal compound is a method for producing a modified conjugated diene-based polymer that is used in 0.1 mmol to 1.0 mmol based on a total amount of monomer 100 g.

The method according to claim 11,
Method of producing a modified conjugated diene-based polymer is further added to the polar additive during the polymerization.

The method according to claim 13,
The polar additive is a method for producing a modified conjugated diene-based polymer is added in an amount of 0.001 to 1.0 parts by weight relative to 100 parts by weight of the total monomer.

The method according to claim 11,
The alkoxysilane-based modifying agent represented by the formula (1) is used in a ratio of 0.05 mol to 3.0 mol relative to 1 mol of the organic alkali metal compound is a method for producing a modified conjugated diene polymer.

A rubber composition comprising the modified conjugated diene-based polymer according to claim 7.

The method according to claim 16,
The rubber composition further comprises 0.1 to 150 parts by weight of a filler based on 100 parts by weight of the modified conjugated diene-based polymer.

The method according to claim 17,
The filler is a rubber composition is a silica-based filler.