KR20060012403A - Rubber compounds for tire tread - Google Patents

Abstract

The present invention relates to a rubber tread composition comprising a terminal modified conjugated diene polymer, wherein the terminal of the living polymer formed by copolymerizing a conjugated diene-based monomer and a vinyl aromatic monomer in the presence of an organolithium catalyst and a hydrocarbon solvent is used as a polyvalent polysiloxane compound ( After coupling with multi-reactive polysiloxanes, the end-modified polymer obtained by modifying the remaining uncoupled ends with a compound of an amine is included in the raw material rubber, including inorganic vulcanizing agents and inorganic fillers such as carbon black and silica. It provides a rubber composition for tire tread that can improve the rolling resistance value and the wet slip resistance value, as well as the improvement of mechanical properties directly related to the physical properties of the tire by mixing.

Description

Rubber compounds for tire treads

The present invention relates to a rubber composition for tire tread, and more particularly, an active terminal formed by copolymerizing a conjugated diene monomer and a vinyl aromatic monomer in the presence of an organolithium catalyst and a hydrocarbon solvent as a multi-reactive polysiloxane compound. A rubber composition for tire treads comprising as a raw material rubber a vulcanizable elastomer obtained by coupling and then modifying the remaining active end with a monovalent amine compound.

Pneumatic tires having a rubber ground plane made of a rubber composition comprising a relatively large amount of silica or silicate are generally referred to as 'green tires'. Generally, the composition of commercialized rubbers generally contains carbon black and silica, and the ratio may vary depending on the application.

When the rubber of a tire in motion is regularly deformed in a relatively low frequency band, the energy is dispersed and the rolling resistance of the car tire is formed. This resistance can be reduced by reducing the energy loss that occurs during operation.

That is, based on the temperature conversion formula Williams-Landel-Ferry equation, the frequency is converted into a function of temperature, and then the dynamic loss factor (tan δ, an exponent of the loss content for energy loss) between 50 and 70 ° C is measured. This value is a measure of rolling resistance.

On the other hand, efforts are being made to increase wet skid resistance in order to improve the braking performance of tires on the surface of the rain which is directly related to stability. The car tires slide on the surface of the road as the driver uses the brake system. At this time, the tread portion of the tire directly in contact with the road surface of the road suffers a lot of energy loss due to the frictional resistance. Since the wet slip resistance is formed by the tire movement of a relatively high frequency band compared to the frequency band at which rolling resistance is formed, the dynamic loss factor value near 0 ° C is a measure of this performance.

As a means of satisfying the two important characteristics of these incompatible tires, styrene-butadiene rubber by emulsion polymerization method, butadiene rubber with high cis content, butadiene rubber with low cis content, natural rubber, and isoprene rubber with high cis content Has been used alone or in combination as raw material rubber. However, using these raw rubbers proved inadequate to satisfy both of the above properties.

On the other hand, in order to obtain a high wet slip resistance value, styrene-butadiene rubber having a high styrene content (for example, having a styrene content of about 30% by weight) or butadiene rubber having a high vinyl content (for example, having a high vinyl content Increase the amount of fillers such as carbon black or oil. However, this method also has the drawback of increasing the rolling resistance value.

When rubber prepared by solution polymerization is used in tires, rotational and wet resistance properties are particularly excellent compared to emulsion-polymerized styrene-butadiene rubber (SBR). In addition, when polymerized using an organolithium catalyst, various functional groups are introduced at the end of the molecule to increase compatibility with carbon black and silica, which are reinforcing materials used in tires, and thus improve wear resistance and rotation. It can reduce the rolling resistance and also improve the wet traction.

Looking at existing methods to increase the compatibility with the carbon black and silica for the conjugated diene polymer obtained through solution polymerization;

First, in order to increase the compatibility between rubber and carbon black, U.S. Patent No. 4,555,548 discloses that the molecular end is modified with an amino benzophenone compound, which is a kind of amine compound, which has superior dynamic properties and mechanical properties. A method for obtaining physical properties is disclosed. However, the rubber produced by this method is poor in processability at the time of blending, and shows a problem of long-term storage due to high cold flow (cold flow) which is an important factor of storage stability. In addition, when the rubber is used for tires using silica as a reinforcing material (hereinafter referred to as silica tire), the rubber is less compatible with silica, and thus, mechanical properties and tire dynamic characteristics (rotation and wet resistance) are inferior. Use has been shown to have no major advantages.

U.S. Patent No. 6,329,467 discloses a technique for reducing the processability and rolling resistance of carbon black blends using a mixture of tin tetrachloride and silicon tetrachloride as a coupling agent, but the polymers thus prepared induce compatibility with reinforcements. The absence of functional groups makes it difficult to produce rubbers suitable for silica tires because of their low compatibility with reinforcements in silica formulations. In particular, since the tin tetrachloride compound dissociates the bond between the tin and the polymer by stearic acid used as a vulcanization accelerator in the compounding, there is a problem of deteriorating the physical properties of the silica compound.

In addition, U.S. Patent No. 6,133,388 introduces a technology for maximizing compatibility with reinforcing materials by modifying the sock end of a molecule into a functional group.However, the compound prepared in this way has a low molecular weight, which is an indicator of the storage stability of the polymer. The value of cold flow is high, and there is a problem in that the blendability is also poor.

U.S. Patent No. 6,013,718 discloses a technique for inducing compatibility with silica by substituting a terminal of a molecule with siloxane, but a substituent containing less amount of siloxane substituted in the molecule and inducing compatibility with carbon black is contained in rubber. There is a problem that the rolling resistance characteristics are deteriorated in a tire that is not used commercially.

Accordingly, there is a demand for development of a tire tread composition using rubber having excellent miscibility in both silica and carbon black, which are fillers used in tire production, and improved mechanical properties and dynamic properties than previously developed polymers.

Accordingly, the present inventors have been researching to develop a rubber having excellent compatibility with silica and also excellent compatibility with carbon black, and then using a polyvalent polysiloxane compound capable of reacting with the anion of a living polymer, then coupling As a result of including rubber modified with an amine compound in an active end, which is not active, the raw material rubber contained mechanically and dynamic properties more remarkably than conventional rubber in rubbers using silica alone, carbon black alone or silica-carbon black mixtures as reinforcing materials. It has been found that the present invention can be improved to complete the present invention.

SUMMARY OF THE INVENTION An object of the present invention is to introduce a dual functional group having different characteristics into a rubber, and thus, a tire tread rubber that can significantly improve mechanical properties, dynamic properties, and low temperature flow properties in the silica-carbon black mixture for tires. It is to provide a composition.

The rubber composition for tire treads of the present invention for achieving the above object includes a raw material rubber, an inorganic filler, sulfur and a vulcanization accelerator, wherein the raw rubber is a conjugated diene monomer and a vinyl aromatic monomer to a hydrocarbon solvent and a Lewis base. Copolymerization in the presence of an organolithium catalyst under the present invention couples the living polymer to the active end with the polyvalent polysiloxane represented by the following formula (1), and then the uncoupled active end is sequentially obtained as one of the compounds represented by the following formula (2) or (3). Characterized in that the terminal modified conjugated diene-based copolymer obtained through the step of modifying to 10 to 100% by weight of the total raw material rubber solid content.                         

(X) _a (R) _b Y- [CH ₂ ] _c -Si (R ¹ ) (R ² )-[O-Si (R ¹ ) (R ² )] _d- [CH ₂ ] _c -Y (X ) _a (R) _b

Wherein X is a halogen atom such as fluorine, chlorine, bromine or iodine; Y is Si or C; R is a lower alkyl group having 20 or less carbon atoms including methyl, ethyl, propyl, and the like; R ¹ is the same as R, or a hydrogen atom, an alkyl group substituted with halogen, or a silane group substituted with halogen; R ² is equal to X or R ¹ ; a is 1 to 3, b is (3-a); c is 1 to 100; d is 1-1000.

(R ₂ ³ NBz) ₂ CO

In which R ³ is It is a lower alkyl group of 20 or less carbon atoms, and Bz is a benzene ring.

Wherein R ⁴ is It is a lower alkyl group of 20 or less carbon atoms.

The present invention will be described in more detail as follows.

The tire tread rubber according to the present invention comprises at least 10% by weight or more of the end-modified conjugated diene copolymer of the raw material rubber.

The terminally modified conjugated diene copolymer is a copolymer of a conjugated diene monomer and a vinyl aromatic monomer in the presence of an organolithium catalyst under a hydrocarbon solvent and a Lewis base to couple a living polymer to a polyhydric polysiloxane represented by Formula 1 at the active end thereof. , Which is obtained through a step of annually denaturing an uncoupled active end with one of the compounds represented by Formula 2 or 3 above.

The conjugated diene monomer used at this time is a butadiene or isoprene compound, and a vinyl aromatic compound is styrene or alphamethyl styrene. Copolymers generally have a composition of 5 to 50% by weight of vinyl aromatic compounds and 50 to 95% by weight of conjugated diene compounds, and when the content of styrene compounds is less than 5% by weight, the wear resistance and the wet resistance are improved. If it is more than 50% by weight can not be expected to improve the wear resistance and exothermic properties.

The monomer is subjected to the conventional procedure of copolymerizing the monomer in a hydrocarbon solvent in the presence of an organolithium catalyst. The organolithium catalyst in forming the living polymer may be a hydrocarbon having at least one lithium atom, such as ethyl lithium, propyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, phenyl lithium, propenyl lithium, Hexyl lithium, 1,4-dirithio-n-butane, 1,3-di (2-lithio-2-hexyl) benzene, and the like, and particularly preferably n-butyl lithium and sec-butyl. Lithium. Such an organolithium catalyst may be used not only as one kind but also as a mixture of two or more kinds. The amount of the organolithium catalyst used may vary depending on the target molecular weight of the resulting polymer, but can be used to generally 0.1 to 5 mmol, preferably 0.3 to 3 mmol, per 100 g of the monomer.

Hydrocarbon solvents used for the polymerization include n-hexane, n-heptane, iso-octane, cyclohexane, methylcyclopentane, benzene, toluene, and the like, and particularly preferably n-hexane, n-heptane, cyclohexane Etc. can be mentioned.

In solution polymerization, the monomers are present in the hydrocarbon solvent at 5 to 40% by weight. More preferably it is advantageous to contain about 10 to 25% by weight of monomers.

The polymerization reaction is initiated by adding an organolithium compound and a Lewis base to the polymerization solution. Lewis base compounds used to control the microstructure of the polymer include tetrahydrofuran, N, N, N, N-tetra methylethylenediamine (TMEDA), di-n-propyl ether, di Di-isopropyl ether, di-n-butyl ether, ethyl butyl ether, triethylene glycol, 1,2-dimethoxybenzene ( 1,2-dimethoxybenzene), trimethylamine and triethylamine are commonly used, of which tetrahydrofuran, N, N, N, and N-tetra methylethylenediamine are preferred. The amount of Lewis base is preferably used in the range of about 50 ppm to 45,000 ppm with respect to the hydrocarbon solvent used for the polymerization.

Typical polymerization initiation temperatures are maintained between about 0 and 60 ° C., with preferred initiation temperatures being maintained between 5 and 50 ° C. If the initiation temperature of the polymerization reaction is lower than 0 ℃, the viscosity of the solution rises rapidly as the reaction proceeds, so that the smooth reaction is difficult and the reaction rate is very slow, it is uneconomical, if it is higher than 60 ℃, the reaction temperature rises rapidly and the reactor temperature It is not easy to adjust. The reaction pressure is suitably 1 to 10 kgf / cm 2.

The polymerization reaction proceeds for a sufficient time until all of the monomers are converted into the copolymer, that is, the polymerization reaction is preferably performed until a high conversion rate is realized. Usually, the reaction time is suitably between 30 minutes and 200 minutes.

At the time when the solution polymerization reaction is completed, the terminal of the living polymer is coupled to the polyvalent polysiloxane compound represented by Chemical Formula 1, and then the residue of the polymer is sequentially used by using one of the compounds represented by Chemical Formula 2 or 3 above. Denature all active ends.

Specific examples of the polyvalent polysiloxane compound represented by Chemical Formula 1 include α, ω-bis (2-trichlorosilylethyl) polydimethylsiloxane, α, ω-bis (2-dichloromethylsilylethyl) polydimethylsiloxane, α, ω-bis (2-chlorodimethylsilylethyl) polydimethylsiloxane and the like. Such polyvalent polysiloxane compounds, unlike conventional polysiloxanes, contain a polar group at the sock end, and thus can react with living polymer anions.

The usage-amount of a polyhydric polysiloxane compound is 0.01-0.5 mol with respect to 1 mol of living polymers, Preferably it is 0.05-0.2 mol.

When coupling the living polymer ends with such polyvalent polysiloxane compounds, the coupling ratio is generally in the range of 30 to 70%, and the remaining uncoupled living polymer ends are replaced with hydrogen by a protic solvent such as alcohol or water. I am inactivated.

The copolymer prepared in this way shows excellent affinity with inorganic silica and excellent control of low temperature flow of rubber at room temperature, but has a limitation in improving affinity with carbon black. There is also a need for more efficient use of uncoupled living polymers.

Thus, in the case of a copolymer coupled with a polyvalent polysiloxane compound, as a method of efficiently utilizing the uncoupled living polymer terminal while solving a problem of inferior affinity with carbon black, the compound represented by Formula 2 or 3 As a result, a method of annual degeneration was introduced.

In other words, the active ends not treated with the polyvalent polysiloxane are sequentially inactivated by adding at least the same molar amount (equimolar amount) as the active ends using the compound represented by Formula 2 or 3 above.

Specific examples of the compound represented by the formula (2) include dimethylaminobenzophenone and diethylaminobenzophenone. Specific examples of the compound represented by the formula (3) include 1-methyl-2-pyrrolidinone and 1-ethyl-2. -Pinolidinone, and the like, of which diethylaminobenzophenone and 1-methyl-2-pyrrolidinone compound are most preferred.

However, if the active end is modified only with a compound represented by the formula (2) or (3), there is no functional group that induces affinity with silica, and there is a limit to its use in silica tires. Although there is a problem of storage, when the coupling is carried out with the polyvalent polysiloxane as in the present invention, the movement of the main chain of the coupled copolymer is significantly lower than the uncoupled state, so that the low temperature flowability is significantly lower. It can be improved to solve storage stability problems.

In addition, when the active terminal is modified with a compound represented by the formula (2) or (3), the compatibility between rubber and carbon black increases. As a result, the copolymer obtained according to the present invention has good compatibility with both silica and carbon black. .

In the case of a rubber compound for tires, if the rubber is mainly used as a reinforcing material, the manufacturing process is preferably performed in a direction of improving the coupling rate of the polyvalent polysiloxane, and if the rubber is mainly carbon black, the coupling rate of the polyvalent polysiloxane is not high. If not, the preparation can be performed according to subsequent amine denaturation.

In the present invention, the coupling ratio of the silica and carbon black mixture is mainly described as about 50%, but those skilled in the art can be variously modified within the technical scope of the present invention. to be.

The pattern viscosity (ML _{1 + 4} @ 100) of the obtained polymer shows the value between 20-200, Preferably it is between 30-160. The vinyl content of the conjugated diene compound in the microstructure is 10 to 90% by weight, preferably 30 to 80% by weight.

Analysis of the polymer synthesized in the present invention is to analyze the microstructure of conjugated diene compound, composition ratio of conjugated diene compound and aromatic vinyl compound, random and block ratio of conjugated diene compound and aromatic vinyl compound using NMR (nuclear magnetic resonance) Coupling number (CN), coupling efficiency (CE), molecular weight (Mw) and molecular weight distribution (Mwd) were analyzed using GPC (Gel permeation chromatography). The pattern viscosities of the rubber were analyzed using a pattern viscometer.

In the tire tread rubber composition using the polymer thus obtained as the raw material rubber, it is preferable that the terminally modified conjugated diene copolymer is 10 to 100% by weight in the raw material rubber. If the content of the terminally modified conjugated diene copolymer in the raw material rubber is less than 10% by weight there is a problem that the desired level of wet resistance and rotational resistance can not be obtained sufficiently.

In addition to such end-modified conjugated diene-based copolymer, the raw material rubber includes raw material rubbers of rubber for general tire tread, and examples thereof include natural rubber, polybutadiene rubber (BR), synthetic polyisoprene rubber (IR), and styrene. Butadiene rubber (SBR) etc. are mentioned.

The inorganic filler may be included in an amount of 10 to 100 parts by weight based on 100 parts by weight of such raw rubber, and the inorganic filler may be silica, carbon black alone, or a mixture thereof. If the content of the inorganic filler is less than 10 parts by weight based on 100 parts by weight of the raw material rubber, the desired level of heat reduction and wetting resistance may not be obtained. If the content of the inorganic filler exceeds 100 parts by weight, there may be a problem of reducing the wear resistance and conductivity of the tire.

In addition, since sulfur is included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the raw material rubber, when the content of sulfur is less than 0.1 part by weight based on 100 parts by weight of the raw material rubber, it is not sufficiently vulcanized. Exceeding the weight part may result in over-crosslinking, which may result in an increase in modulus and wear.

In addition, the present invention may include compounding agents added to a rubber composition for a tire tread, for example, and include a silane coupling agent when stearic acid, zinc oxide, process oil, and silica are included as inorganic fillers. Can be.

The present invention will be described in detail with reference to Examples. The following example illustrates the preparation method of the SBR random copolymer according to the present invention, the degree of coupling, the pattern viscosity, and the degree of vinyl bond formation in the polymer. The embodiments described herein are for the purpose of illustrating the invention only and are not intended to limit the scope of the invention. All percentages are by weight unless otherwise indicated.

Production Example  One

150 g of styrene, 438 g of 1,3-butadiene, and 2,400 g of cyclohexane were fed to a 10 L stainless reactor, followed by 84 g of tetrahydrofuran. When the addition was completed, the temperature inside the reactor was adjusted to 25 ° C. while turning the stirrer. When the reactor temperature reached the set temperature, 4 mmol of n-butyllithium was added to the reactor to proceed with the adiabatic heating reaction. The degree of polymerization was determined by observing the reaction temperature change, and a small amount of the reactant was taken from time to time to analyze the monomer ratio and the reaction conversion rate. When the reaction temperature reached the maximum temperature, 12 g of additional 1,3-butadiene was added to replace the reaction terminal with butadiene.

When the additional butadiene supply was completed, 0.5 mmol of the coupling agent α, ω-bis (2-trichlorosilylethyl) polydimethylsiloxane having a number average molecular weight (Mn) of 1,345 was supplied to the reactor, and the coupling reaction was then allowed to stand for a predetermined time. .

After the coupling reaction was completed, 2mmol of 4,4-diethylaminobenzophenone was added to the reactor to replace the uncoupled active terminal with 4,4-diethylaminobenzophenone, followed by antioxidant BHT (butylated hydroxy). 6 g (1 phr) of toluene) was added to the reactor to terminate the reaction. The polymer was poured into hot water heated with steam, stirred to remove the solvent, and then roll dried to remove the residual amount of solvent and water.

The molecular microstructure using NMR, the molecular weight, the number of coupling, the coupling ratio and the molecular weight distribution were measured by cold flow meter using GPC, and the dynamic properties of rubber were analyzed by DMTA. The results are shown in Table 1 below.

Production Example  2

The copolymer was prepared in the same manner as in Preparation Example 1, but 3.4 mmol of n-butyllithium was added to proceed with the reaction. When the addition of butadiene was completed, the coupling agent α, ω-bis (Mn) having a number average molecular weight (Mn) of 1,345 ( 2-trichlorosilylethyl) 0.3 mmol of polydimethylsiloxane was fed to the reactor, followed by coupling reaction.

After the coupling reaction was completed, 2.2 mmol of 4,4-diethylaminobenzophenone was added to the reactor to replace the uncoupled active terminal with 4,4-diethylaminobenzophenone, followed by 6 g (1 phr) of antioxidant BHT. The reaction was terminated by adding to the reactor. After completion of the reaction, the polymer was treated in the same manner as in Preparation Example 1, and the analysis results for the polymer are shown in Table 1 below.

Production Example  3

Prepare a copolymer in the same manner as in Preparation Example 1, but proceed with the reaction by adding 4.6mmol of n-butyllithium and the coupling agent α, ω-bis (2) having a number average molecular weight (Mn) of 1,345 when the addition of butadiene is completed -Trichlorosilylethyl) 0.75 mmol of polydimethylsiloxane was fed to the reactor, and then allowed to stand for a certain time to proceed with the coupling reaction.

After the coupling reaction was completed, 1.6 mmol of 4,4-diethylaminobenzophenone was added to the reactor to replace the uncoupled active terminal with 4,4-diethylaminobenzophenone, followed by 6 g (1 phr) of antioxidant BHT. The reaction was terminated by adding to the reactor. After completion of the reaction, the polymer was treated in the same manner as in Preparation Example 1, and the analysis results for the polymer are shown in Table 1 below.

Production Example  4

Prepare a copolymer in the same manner as in Preparation Example 1, but when the coupling reaction is completed, 1 mmol of 1-methyl-2-pinolidinone is added to the reactor to terminate the uncoupled active terminal 1-methyl-2-pinolidinone After the substitution, 6 g (1 phr) of antioxidant BHT was added to the reactor to terminate the reaction. After completion of the reaction, the polymer was treated in the same manner as in Preparation Example 1, and the analysis results for the polymer are shown in Table 1 below.

Production Example  5

The copolymer was prepared in the same manner as in Preparation Example 4, but the reaction proceeded by adding 3.4 mmol of n-butyllithium, and when the addition of butadiene was completed, the coupling agent α, ω having a number average molecular weight (Mn) of 1,345. 0.3 mmol of bis (2-trichlorosilylethyl) polydimethylsiloxane was fed to the reactor, followed by coupling reaction.

After the coupling reaction was completed, 2.2 mmol of 1-methyl-2-pinolidinone was added to the reactor to replace the uncoupled active terminal with 1-methyl-2-pinolidinone, followed by 6 g (1 phr) of antioxidant BHT. The reaction was terminated by adding to the reactor. After completion of the reaction, the polymer was treated in the same manner as in Preparation Example 1, and the analysis results for the polymer are shown in Table 1 below.

Production Example  6

A copolymer was prepared in the same manner as in Preparation Example 4, but the reaction was carried out by adding 4.6 mmol of n-butyllithium, and the coupling agent α, ω-bis (2) having a number average molecular weight (Mn) of 1,345 was completed. -Trichlorosilylethyl) 0.75 mmol of polydimethylsiloxane was fed to the reactor, and then allowed to stand for a certain time to proceed with the coupling reaction.

After the coupling reaction was completed, 1.6 mmol of 1-methyl-2-pinolidinone was added to the reactor to replace the uncoupled active terminal with 1-methyl-2-pinolidinone, followed by 6 g (1 phr) of antioxidant BHT. The reaction was terminated by adding to the reactor. After completion of the reaction, the polymer was treated in the same manner as in Preparation Example 1, and the analysis results for the polymer are shown in Table 1 below.

Comparative Production Example  One

A copolymer was prepared in the same manner as in Preparation Example 1, but after completion of the coupling reaction, 6 g (1 phr) of antioxidant BHT was added to the reactor to terminate the reaction. After completion of the reaction, the polymer was treated in the same manner as in Preparation Example 1, and the analysis results for the polymer are shown in Table 1 below.

Comparative Production Example  2

The reaction was carried out in the same manner as in Preparation Example 1, but the reaction proceeded by adding 2.3mmol of n-butyllithium, and 2.3mmol of 4,4, -bis-diethylamino benzophenone when the addition of 1,3-butadiene was completed. Was injected into the reactor, and the active ends were all terminally modified with 4, 4, -bis-diethyl amino benzophenone. After the end denaturation was completed, 6 g (1 phr) of antioxidant BHT was added to the reactor and the polymer was treated in the same manner as in Preparation Example 1, and the analysis results thereof are shown in Table 1 below.

Comparative Production Example  3

The reaction was conducted in the same manner as in Preparation Example 1, but when additional 1,3-butadiene was added, 2.3 mmol of 1-methyl-2-pyrrolidinone was added to the reactor to activate 1-methyl-2-pyrroli. Terminal denatured all with dinon. After the end denaturation was completed, 6 g (1 phr) of antioxidant BHT was added to the reactor and the polymer was treated in the same manner as in Preparation Example 1, and the analysis results thereof are shown in Table 1 below.

Coupling Rate (%) Coupling Number Mw Pattern viscosity (M _{L 1 + 4,} 100 ℃) Styrene Content (%) Vinyl content                                                  (%)^(One)                                              Low Temperature Flow (mg / min.) ⁽³⁾ Example 1 52 4.2 391,000 53 25 62 0.0 Example 2 36 4.3 379,000 51 25 62 0.51 Example 3 64 4.1 385,000 52 25 62 0.0 Example 4 51 4.2 388,000 52 25 62 0.0 Example 5 34 4.3 383,000 51 25 62 0.62 Example 6 66 4.1 385,000 52 25 62 0.0 Comparative Example 1 50 4.2 388,000 51 25 62 0.0 Comparative Example 2 - - 296000 49 25 62 6.5 Comparative Example 3 - - 288000 49 25 62 6.2  (Note) (1) NMR analysis result (2) Molecular weight distribution: It shows the distribution of total molecular weight. (3) Measured in 50 ℃ convection vacuum oven

Example  One To 9

In this example, silica was blended using the respective polymers obtained according to Production Examples 1 to 6 and Comparative Production Examples 1 to 3 to compare the blendability and the physical and dynamic properties after blending. Compounding conditions are shown in Table 2 below. Mechanical and dynamic properties measurement results are shown in Table 3 below.

Specific measuring methods are as follows.

Hardness was measured using a SHORE-A hardness tester, tensile strength, 300% modulus and elongation of the rubber compound was measured using a universal test machine according to ASTM 3189 Method B method. Tanδ value, which is a dynamic property value of the vulcanized rubber, was analyzed under a strain condition of 10 Hz and 0.1% using a DMTA 5 device of Rheometric.

Formulation Composition Content (g) Polymer 100 Stearic acid 2.0 ZnO 3.0 Silica # 175 50 Aromatic oil 10 Si-69 4.0 CZ 2.0 DPG 2.0 Sulfur 1.6 Total 184.6 * Si-69: Bis- (triethoxysilylpropyl) tetrasulfane * DPG: 1,3-Diphenyl guanidine * CZ: N-Cyclohexylbenzothiazyl sulfenamide

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Mounds division Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 Preparation Example 6 Comparative Preparation Example 1 Comparative Production Example 2 Comparative Production Example 3 Coupling agent PS ^* PS ^* PS ^* PS ^* PS ^* PS ^* PS ^* - - Terminal substituent EAB ^** EAB ^** EAB ^** NMP ^*** NMP ^*** NMP ^** - EAB ^** NMP ^*** PS / EAB (NMP) ratio (%) 52/48 36/64 64/36 51/49 34/66 66/34 50/0 0/100 0/100 Compound pattern viscosity ¹⁾ 92 93 91 91 94 90 90 103 101  Hardness (Shore-A) 76 76 76 76 76 76 76 75 75  Tensile Strength (kgf / ㎠) 190 180 205 187 185 200 185 167 160  300% modulus (kgf / ㎠) 154 160 155 157 161 155 156 140 143  Elongation (%) 380 380 390 400 400 410 380 370 350  Tg (℃) 1.1 -1.0 1.5 0.9 0.2 1.8 -0.8 -2.7 -2.5  tan δ at 10 ℃ 0.5073 0.4982 0.5271 0.5123 0.5101 0.5357 0.4882 0.4552 0.4328  tan δ at 60 ℃ 0.0674 0.0679 0.0651 0.0654 0.0657 0.0633 0.0689 0.0721 0.0752 * PS: polyvalent polysiloxane (Mn 1345), ** EAB: 4,4-bis diethyl amino benzophenone *** NMP: 1-methyl-2-pinolidinone

Example  10 To 18

In this embodiment, carbon black was blended using the polymers obtained according to Production Examples 1 to 6 and Comparative Production Examples 1 to 3 to compare the blendability and the physical properties and dynamic properties after blending. Compounding conditions are shown in Table 4 below. The results of measuring the mechanical and dynamic properties by the above-described method are shown in Table 5 below.

Item Content (g)  Polymer 100 Carbon black (N-330) 50  ZnO 3.0 SA 1.0  Sulfur 1.75 NS 1.00 Total 1.0 * SA: Stearic Acid * NS: N- (1,1-dimethylethyl) -2-benzothiazolsulfoneamide

Example 10 Example 11 Example 12 Example 13 Example 14 Example 15 Example 16 Example 17 Example 18 Mounds division Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 Preparation Example 6 Comparative Preparation Example 1 Comparative Production Example 2 Comparative Production Example 3 Coupling agent PS ^* PS ^* PS ^* PS ^* PS ^* PS ^* PS ^* - - Terminal substituent EAB ^** EAB ^** EAB ^** NMP ^*** NMP ^*** NMP ^*** - EAB ^** NMP ^*** PS / EAB (NMP) ratio (%) 52/48 36/64 64/36 51/49 34/66 66/34 50/0 0/100 0/100  Compound pattern 105 101 102 103 105 103 99 110 112 Shore-A 74 74 74 74 74 74 74 73 73  Tensile Strength (kgf / ㎠) 235 241 215 230 235 220 195 205 202 300% modulus (kgf / ㎠) 185 180 178 182 195 190 180 178 175  Elongation (%) 430 480 360 410 460 470 400 410 420  Tg (℃) 1.7 1.9 0.5 1.5 1.8 0.39 -1.0 0.3 0.1  tan δ at 10 ℃ 0.5583 0.5887 0.5641 0.5685 0.5877 0.5652 0.5245 0.5341 0.5451  tan δ at 60 ℃ 0.0951 0.0886 0.0892 0.0945 0.0857 0.0891 0.0962 0.0952 0.0978  * PS: polyvalent polysiloxane (Mn 1345), ** EAB: 4,4-bis diethyl amino benzophenone *** NMP: 1-methyl-2-pinolidinone

Example  19 To 27

In this example, silica-carbon black blending was carried out as an application blend using the polymers obtained according to Production Examples 1 to 6 and Comparative Production Examples 1 to 3 to compare the blendability and the physical and dynamic properties after blending. Compounding conditions are shown in Table 6 below. As a result of measuring the mechanical and dynamic properties by the method described above is shown in Table 7 below.

Item Content (g)  Polymer 100  Stearic acid 2.0  ZnO 3.0 Silica # 175 20 Carbon black (N-330) 30  Aromatic oil 18.0  Si-69 1.6  CZ 2.0  DPG 2.0  Sulfur 1.5 Total 180.1  * Si-69: Bis- (triethoxysilylpropyl) tetrasulfane * DPG: 1,3-Diphenyl guanidine * CZ: N-Cyclohexylbenzothiazyl sulfenamide

Example 19 Example 20 Example 21 Example 22 Example 23 Example 24 Example 25 Example 26 Example 27 Mounds division Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 Preparation Example 6 Comparative Preparation Example 1 Comparative Production Example 2 Comparative Production Example 3 Coupling agent PS ^* PS ^* PS ^* PS ^* PS ^* PS ^* PS ^* - - Terminal substituent EAB ^** EAB ^** EAB ^*** NMP ^*** NMP ^*** NMP ^*** - EAB ^** NMP ^*** PS / EAB (NMP) ratio (%) 52/48 36/64 64/36 51/49 34/66 66/34 50/0 0/100 0/100  Compound pattern 49 51 47 48 52 48 48 59 61  Hardness (Shore-A) 66 66 66 66 66 66 66 65 65  Tensile Strength (kgf / ㎠) 195 189 190 193 187 188 178 173 172  300% modulus (kgf / ㎠) 110 108 103 105 105 106 98 110 108  Elongation (%) 500 510 520 510 510 550 510 450 480  Tg (℃) -0.2 -0.1 -0.15 -0.2 -0.05 -0.1 -1.5 -3.1 -2.8  tan δ at 10 ℃ 0.5583 0.5621 0.5498 0.5589 0.5684 0.5546 0.4995 0.4586 0.4748  tan δ at 60 ℃ 0.0732 0.0751 0.0762 0.0725 0.0754 0.0762 0.0785 0.0896 0.0889

Example  28 To 36

In this embodiment, as a raw material rubber, a copolymer obtained according to the above production examples and comparative production examples and high-Cis butadiene rubber are mixed and used in the following ratios. Silica-carbon black blending was performed to compare blendability and physical and dynamic properties after blending. Compounding conditions are shown in Table 8 below. As a result of measuring the mechanical and dynamic properties by the method described above is shown in Table 9 below.

Item Content (g) Solution SBR 110 Butadiene rubber 20  Stearic acid 2.0  ZnO 3.0 Silica # 175 20 Carbon black (N-330) 30  Aromatic oil 18.0  Si-69 1.6  CZ 2.0  DPG 2.0  Sulfur 1.5 Total 180.1 * Si-69: Bis- (triethoxysilylpropyl) tetrasulfane * DPG: 1,3-Diphenyl guanidine * CZ: N-Cyclohexylbenzothiazyl sulfenamide

Example 28 Example 29 Example 30 Example 31 Example 32 Example 33 Example 34 Example 35 Example 36 Mounds division Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 Preparation Example 6 Comparative Preparation Example 1 Comparative Production Example 2 Comparative Production Example 3 Coupling agent PS ^* PS ^* PS ^* PS ^* PS ^* PS ^* PS ^* - - Terminal substituent EAB ^** EAB ^** EAB ^*** NMP ^*** NMP ^*** NMP ^*** - EAB ^** NMP ^*** PS / EAB (NMP) ratio (%) 52/48 36/64 64/36 51/49 34/66 66/34 50/0 0/100 0/100  Compound pattern 45 43 42 41 45 43 46 52 55  Hardness (Shore-A) 64 64 64 64 64 64 64 63 63  Tensile Strength (kgf / ㎠) 200 194 195 198 192 193 183 178 177  300% modulus (kgf / ㎠) 107 102 98 95 97 99 98 96 97  Elongation (%) 520 530 540 520 560 530 540 490 500  Tg (℃) -15.2 -15.1 -15.3 -15.2 -15.05 -15.1 -16.5 -18.1 -17.8  tan δ at 0 ℃ 0.4536 0.4632 0.4611 0.4711 0.4615 0.4687 0.4492 0.4501 0.4456  tan δ at 60 ℃ 0.0692 0.0681 0.0678 0.0688 0.0681 0.0679 0.0712 0.0724 0.0732

As described above in detail, the polyhydric polysiloxane compound represented by Chemical Formula 1 according to the present invention is one of the compounds represented by Chemical Formula 2 or 3, wherein the living polymer terminals remaining after coupling the living polymer terminals are continuously connected. When the rubber composition prepared by modifying the end of the molecule with various additives is applied to the tire tread, the polyhydric polysiloxane coupling provides good affinity with silica and affinity with carbon black due to amine end modification. The increased compatibility with silica and carbon black, a reinforcing material used to make tires, increases significantly compared to existing products. Ultimately, silica-carbon black mixtures as well as carbon black and silica alone are used as inorganic fillers. If inorganic fillers are used, The wear resistance required for the tire in the manufactured rubber composition can also exhibit improved performance and desirable high wetting resistance and low rolling resistance.

Claims (10)

In the rubber composition for tire tread containing raw rubber, inorganic filler, sulfur and vulcanization accelerator, The raw material rubber is copolymerized with a conjugated diene-based monomer and a vinyl aromatic monomer in the presence of an organolithium catalyst under a hydrocarbon solvent and a Lewis base to couple the living polymer to the polyhydric polysiloxane represented by the following Chemical Formula 1 at the active end, and then not coupled. Characterized in that it comprises 10 to 100% by weight of the end-modified conjugated diene-based copolymer obtained through the step of serially denaturing the active terminal is not one of the compounds represented by the formula (2) or (3) Tire tread rubber composition. Formula 1 (X) _a (R) _b Y- [CH ₂ ] _c -Si (R ¹ ) (R ² )-[O-Si (R ¹ ) (R ² )] _d- [CH ₂ ] _c -Y (X ) _a (R) _b Wherein X is a halogen atom such as fluorine, chlorine, bromine or iodine; Y is Si or C; R is a lower alkyl group having 20 or less carbon atoms including methyl, ethyl, propyl, and the like; R ¹ is the same as R, or a hydrogen atom, an alkyl group substituted with halogen, or a silane group substituted with halogen; R ² is equal to X or R ¹ ; a is 1 to 3, b is (3-a); c is 1 to 100; d is 1-1000. Formula 2 (R ₂ ³ NBz) ₂ CO In which R ³ is It is a lower alkyl group of 20 or less carbon atoms, and Bz is a benzene ring. Formula 3

Wherein R ⁴ is It is a lower alkyl group of 20 or less carbon atoms. The rubber for tire tread according to claim 1, wherein the terminally modified conjugated diene polymer is obtained by using 1,3-butadiene or isoprene as the conjugated diene monomer and styrene or alpha methyl styrene as the vinyl aromatic monomer. Composition. The terminally modified conjugated diene-based polymer according to claim 1, wherein the terminally modified conjugated diene-based polymer is a polyvalent polysiloxane represented by the formula (1), and α, ω-bis (2-trichlorosilylethyl) polydimethylsiloxane, α, ω-bis (2-dichloromethyl A rubber composition for a tire tread, characterized in that it is produced using at least one selected from the group consisting of silylethyl) polydimethylsiloxane and α, ω-bis (2-chlorodimethylsilylethyl) polydimethylsiloxane. According to claim 1, wherein the terminal modified conjugated diene polymer is a compound represented by the formula (2) dimethyl amino benzophenone or diethyl amino benzophenone, the compound represented by the formula (3) is 1-methyl-2-pinolidinone or 1 A rubber composition for tire treads, characterized in that it is prepared using ethyl-2-pinolidinone. The rubber composition for tire treads according to claim 1, wherein the terminal-modified conjugated diene polymer is prepared by using the polyvalent polysiloxane represented by Chemical Formula 1 so as to be 0.01 to 0.5 moles based on 1 mole of the living polymer. The rubber composition for a tire tread according to claim 1, wherein the living polymer comprises 5 to 50% by weight of a vinyl aromatic monomer and 50 to 95% by weight of a conjugated diene compound. The rubber composition for tire treads according to claim 1, wherein the terminally modified conjugated diene polymer has a molecular weight in the range of 10,000 to 1,500,000. The tire tread of claim 1, wherein the terminally modified conjugated diene-based polymer is prepared by using the compound represented by Chemical Formula 2 or 3 in an amount of 10% or more of the remaining mole ratio of the living polymer which is not coupled to the polyvalent polysiloxane. Rubber composition. 2. The rubber composition for tire tread according to claim 1, wherein the raw material rubber is selected from natural rubber, polybutadiene rubber (BR), synthetic polyisoprene rubber (IR), and styrene-butadiene rubber (SBR). The rubber composition for tire treads according to claim 1, wherein the inorganic filler comprises 10 to 100 parts by weight based on 100 parts by weight of the raw material rubber or a mixture thereof selected from silica and carbon black.