KR20190083047A - Rubber composition for tire tread and tire manufactured by using the same - Google Patents

Abstract

The present invention relates to a rubber composition for tire tread having improved electric conductivity, dispersion stability and wear resistance by comprising 60 to 130 parts by weight of a filler, 5 to 20 parts by weight of a conductive polymer and 5 to 20 parts by weight of vegetable oil with respect to 100 parts by weight of raw rubber, and to a tire manufactured by using the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a rubber composition for a tire tread, and a tire produced using the same. BACKGROUND OF THE INVENTION [0002]

The present invention relates to a rubber composition for a tire tread having improved electrical conductivity, dispersion stability and abrasion resistance, and a tire produced using the same.

In addition to the main rubber component, tires use a variety of additives to enhance or enhance the properties needed for tires.

As automobiles become more sophisticated, the demand for braking performance and fuel-efficiency performance on wet road surfaces of tires has been strengthened. In order to satisfy the required performance, rubber compositions for treads in which carbon black is replaced with silica have been increasing. However, unlike carbon black, silica has a structure in which electrons are difficult to migrate, and thus electric conductivity tends to decrease. As a result, the static electricity generated in the vehicle body can not escape to the ground through the tire, and the flame generated in this process may lead to an explosion when it is transferred to gasoline.

Conventionally, in order to improve the electrical conductivity, a rubber composition containing a metal powder or a conductive filler applied in a certain direction has been applied. However, the weight of the rubber composition is increased and there is a technical difficulty in manufacturing. There is also a method of discharging static electricity through a thin rubber composition using a conductive filler on the surface of the tread, but the tire tread wears due to running, and the discharge effect gradually decreases. Korean Patent Laid-Open Publication No. 2010-0058727 proposes a mixture of silica and general-purpose carbon black to solve the process difficulties. However, the rubber composition has limitations in meeting the performance requirements of consumers for fuel efficiency and wet road surface braking performance, and the rubber composition has been supplemented with a process technique of protruding or in- serting the static bar from the under-tread. Accordingly, there is a need for a rubber composition capable of discharging static electricity while maintaining the tire performance without requiring a process complement.

It is an object of the present invention to provide a rubber composition for a tire tread having improved electrical conductivity, dispersion stability and abrasion resistance.

Another object of the present invention is to provide a tire produced by using the rubber composition for a tire tread.

The present invention provides a rubber composition for tire tread comprising 100 parts by weight of raw rubber, 60 to 130 parts by weight of silica, 5 to 20 parts by weight of conductive polymer, and 5 to 20 parts by weight of vegetable oil.

The conductive polymer may be at least one selected from the group consisting of poly (3-alkyl-thiophene), polyacetylene, polyaniline, polythiophene, Poly (1,4-phenylenevinylene), poly (1,4-phenylenesulfide), poly (fluorenyleneethynylene) And a mixture thereof.

The conductive polymer may be represented by the following general formula (1).

≪ Formula 1 >

(n is a natural number of 5 to 50,000,

And R is any one selected from the group consisting of an alkyl group, an alkoxy group, an alkylene alkoxy group and a polyalkylene oxide group.

The vegetable oil may be any one selected from the group consisting of soybean oil, sunflower oil, canola oil, grape seed oil, and mixtures thereof.

The vegetable oil may be soybean oil containing 40 to 60% by weight of linoleic acid, 10 to 30% by weight of oleic acid, and the remaining amount of fatty acids other than the two.

The rubber composition for a tire tread according to claim 1, wherein 1.5 to 2.5 parts by weight of a vulcanizing agent, 0.5 to 2.5 parts by weight of a vulcanization accelerator, 1 to 5 parts by weight of zinc oxide, 0.5 to 3 parts by weight of stearic acid, 1 to 10 parts by weight.

The present invention also provides a tire produced using the rubber composition for a tire tread.

The present invention can provide a rubber composition for a tire tread having improved electrical conductivity, dispersion stability and abrasion resistance.

The present invention can also provide a low-weight eco-friendly tire using the rubber composition for a tire tread.

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

The rubber composition for tire tread according to the present invention comprises 100 parts by weight of raw rubber, 60 to 130 parts by weight of silica, 5 to 20 parts by weight of conductive polymer, and 5 to 20 parts by weight of vegetable oil.

In the rubber composition for a tire tread, the raw material rubber may be any one selected from the group consisting of natural rubber, synthetic rubber, and combinations thereof.

The natural rubber has excellent tensile strength and abrasion resistance and can be used without particular limitation as long as it is generally used in a tire rubber composition. Specifically, the natural rubber may be a general natural rubber or a modified natural rubber.

The natural rubber includes cis-1,4-polyisoprene as a main component, but may also include trans-1,4-polyisoprene depending on required characteristics. Therefore, in addition to natural rubber containing cis-1,4-polyisoprene as a main component, natural rubber including trans-1,4-isoprene as a main component, such as balata, Rubber may also be included.

The modified natural rubber means that the natural rubber is denatured or purified. Examples of the modified natural rubber include deproteinized natural rubber (DPNR), hydrogenated natural rubber, and the like.

The synthetic rubber may be at least one selected from the group consisting of styrene butadiene rubber (SBR), modified styrene butadiene rubber, butadiene rubber (BR), modified butadiene rubber, polyisoprene rubber, butyl rubber (BR), chlorosulfonated polyethylene rubber, Butadiene rubber (NBR), modified nitrile butadiene rubber, chlorinated polyethylene rubber, styrene ethylene butylene styrene (SEBS) rubber, ethylene propylene rubber, ethylene propylene diene ( EPDM) rubber, hyaluron rubber, chloroprene rubber, ethylene vinyl acetate rubber, acrylic rubber, hydrin rubber, vinyl benzyl chloride styrene butadiene rubber, bromomethyl styrene butyl rubber, maleic styrene butadiene rubber, carboxylic acid styrene butadiene rubber, epoxy Isoprene rubber, ethylene propylene maleate It may be a p-methyl styrene (brominated polyisobutyl isoprene-co-paramethyl styrene, BIMS), and one selected from the group consisting of -, carboxylic acid nitrile-butadiene rubber, polyisobutylene isoprene bromo mineyi lactide-co.

The rubber composition for tire tread may include silica as a reinforcing filler, and further, a silane coupling agent may be further added to improve the dispersibility of silica.

The silica may be contained in an amount of 60 to 130 parts by weight based on 100 parts by weight of the raw rubber. When the amount of the silica is less than 60 parts by weight, there is a problem that the braking performance is poor. When the amount is more than 130 parts by weight, abrasion resistance and low fuel consumption performance are disadvantageous.

The silica is preferably a highly disperse silica having a nitrogen adsorption amount of 160 to 180 m 2 / g, a CTAB value of 150 to 170 m 2 / g, and a DBP oil absorption of 180 to 200 cc / 100 g in order to obtain a tread rubber composition suitable for the purpose of the present invention .

The silane coupling agent includes bis (trialkoxysilylpropyl) polysulfide (TESPD) and bis-3-triethoxysilylpropyltetrasulfide (TESPT) in an alkoxy polysulfide silane compound. TESPD is a mixture of TESPT and carbon black 50 %. The silane coupling agent is preferably used in an amount of 10 to 20 parts by weight based on 100 parts by weight of the raw material rubber.

In order to satisfy required performance such as braking performance on a wet road surface of automobile and low fuel consumption performance, a rubber composition for tread in which carbon black is replaced by silica is increasing. However, unlike carbon black, Conductivity tends to decrease. As a result, the static electricity generated in the vehicle body can not escape to the ground through the tire, and the flame generated in this process may lead to an explosion when it is transferred to gasoline.

Conventionally, in order to improve the electrical conductivity, a rubber composition containing a metal powder or a conductive filler applied in a certain direction is applied, but the weight is increased and technically difficult to manufacture. In addition, there is a method of discharging static electricity through a thin rubber composition using a conductive filler on the surface of the tread, but the tire tread wears due to running, and the discharging effect gradually decreases, and as the rubber composition, the fuel consumption and the wet road surface braking performance There is a limitation in meeting the performance requirements of consumers, and it is necessary to compensate the static bars such as protruding from the under tread or implanting them.

In order to solve such problems, the present invention has applied the conductive polymer to the rubber composition for tire tread.

The conductive polymer may be at least one selected from the group consisting of poly (3-alkyl-thiophene), polyacetylene, polyaniline, polythiophene, Poly (1,4-phenylenevinylene), poly (1,4-phenylenesulfide), poly (fluorenyleneethynylene) And a mixture thereof, and most preferably poly (3-alkyl-thiophene) having the highest electric conductivity among the conductive polymers may be used.

The conductive polymer may be represented by the following general formula (1).

≪ Formula 1 >

In Formula 1, n may be a natural number of 5 to 50,000.

The R may be any one selected from the group consisting of an alkyl group, an alkoxy group, an alkylene alkoxy group and a polyalkylene oxide group, and the functional group may have 2 to 20 carbon atoms.

The conductive polymer may be included in an amount of 5 to 20 parts by weight based on 100 parts by weight of the raw rubber. If the content of the conductive polymer is less than 5 parts by weight based on 100 parts by weight of the raw material rubber, the effect of improving the conductivity is insignificant. If it exceeds 20 parts by weight, the workability and dispersibility may be lowered.

The rubber composition for a tire tread according to the present invention is capable of discharging electrostatic electricity without a process complementary to the static electricity bar. Particularly, since the conductive polymer is smaller in weight than a metal material or carbon black, .

However, the Mooney viscosity and dispersibility of the rubber composition may be lowered by adding the conductive polymer. Therefore, the present invention supplements the above-mentioned problem by using vegetable oil instead of the process oil such as general TDAE.

The rubber composition for a tire tread according to the present invention can improve both the wear performance and the braking performance by lowering the increased glass transition temperature (Tg) of the rubber composition for a tire tread by using the conductive polymer and the vegetable oil in combination.

The vegetable oil may be any one selected from the group consisting of soybean oil, sunflower oil, canola oil, grape seed oil, and mixtures thereof, and most preferably is soybean oil.

It is most preferred that the vegetable oil contains 40 to 60 wt% of linoleic acid, 10 to 30 wt% of oleic acid, and the remaining amount of fatty acids other than the total weight of the vegetable oil.

When the content of linolenic acid is less than 40% by weight, compatibility between the rubber composition and the conductive polymer is deteriorated, and when it exceeds 60% by weight, volatility increases and workability may be deteriorated.

When the content of the oleic acid is less than 10% by weight, the effect of lowering the glass transition temperature (Tg) of the rubber composition is insignificant. When the oleic acid content is more than 30% by weight, the tire braking performance may deteriorate on the wet road surface .

Soybean oil, a vegetable oil, has a high molecular weight and contains unsaturated fatty acids compared to general TDAE (Treated Distillate Aromatic Extract) process oil. The double bond of the unsaturated fatty acid increases the plasticizing effect, which is advantageous in dispersing the rubber composition. That is, the conductive polymer is used to improve the electrical conductivity, and the vegetable oil is used to increase the dispersibility, thereby improving the wear characteristics.

The vegetable oil is preferably used in an amount of 5 to 20 parts by weight based on 100 parts by weight of the starting rubber, and the vegetable oil is preferably used in a weight ratio of 1: 1 to 1: 2 relative to the conductive polymer. When the vegetable oil is contained in an amount of less than 1 part by weight based on 1 part by weight of the conductive polymer, there is no effect of controlling the glass transition temperature of the rubber composition for tread. When the vegetable oil is more than 2 parts by weight, the abrasion performance and braking performance are excessively lowered Lt; / RTI >

In addition, the vegetable oil can replace the use of process oil containing a large amount of PAHs (Polycyclic Aromatic Hydrocarbons), which is a toxic substance that causes cancer, and is beneficial to the human body and eco-friendly.

The vegetable oil may be one obtained by extracting oil components using a compression method or a solvent extraction method using one or more materials selected from soybean, sunflower, canola and grape seed.

First, the pressing method may be a washing step, a drying step, a milking step, an aging step and a precipitation step. The drying step may be a step of washing the selected material, followed by drying for 2 to 3 hours in an inhalation ventilation drying method at a low temperature of 50 to 70 ° C. The milking step may be to extract the oil from the dried material at 80 to 90 DEG C with a conventional compactor or an experma machine. In the aging and precipitation step, the oil evacuated through the milking process is aged at room temperature for 7 to 10 days, and the foreign substances are precipitated to remove precipitates to separate only clear oil.

Next, solvent extraction may be carried out using an organic solvent such as hexane, alcohol, acetone, benzene, chloromethane, ether or the like. The soybeans may be immersed in the organic solvent to extract the oil components and separate only the oil.

The rubber composition for a tire tread may further include various additives such as an additional vulcanizing agent, a vulcanization accelerator, a vulcanization accelerator, and an anti-aging agent. The various additives can be used as long as they are commonly used in the field to which the present invention belongs. The content thereof is not particularly limited as long as it depends on a compounding ratio used in a rubber composition for a tire tread.

As the vulcanizing agent, metal oxides such as sulfur vulcanizing agents, organic peroxides, resin vulcanizing agents, and magnesium oxide can be used.

The sulfur vulcanizing agent is an inorganic vulcanizing agent such as powder sulfur (S), insoluble sulfur (S), precipitated sulfur (S), colloid sulfur, etc., tetramethylthiuram disulfide (TMTD) Organic vulcanizing agents such as tetraethyltriuram disulfide (TETD) and dithiodimorpholine can be used. As the sulfur vulcanizing agent, a vulcanizing agent which produces elemental sulfur or sulfur, for example, amine disulfide, polymer sulfur and the like can be used.

The organic peroxide is selected from the group consisting of benzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, t-butyl cumyl peroxide, methyl ethyl ketone peroxide, cumene hydroperoxide, 2,5- butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5- Bis (t-butylperoxypropyl) benzene, di-t-butylperoxy-diisopropylbenzene, t-butylperoxybenzene, 2,4-dichlorobenzoylperoxide, 1,1- , 3,5-trimethylsiloxane, n-butyl-4,4-di-t-butylperoxyvalerate, and combinations thereof.

It is preferable that the vulcanizing agent is included in an amount of 1.5 to 2.5 parts by weight based on 100 parts by weight of the raw material rubber in view of proper vulcanization effect because the raw rubber is less sensitive to heat and chemically stable.

The vulcanization accelerator refers to an accelerator that promotes the vulcanization rate or accelerates the retardation in the initial vulcanization step.

Examples of the vulcanization accelerator include sulfenamide, thiazole, thiuram, thiourea, guanidine, dithiocarbamate, aldehyde-amine, aldehyde-ammonia, imidazoline, Or a combination thereof.

Examples of the sulfenamide type vulcanization accelerator include N-cyclohexyl-2-benzothiazyl sulfenamide (CBS), N-tert-butyl-2-benzothiazyl sulfenamide (TBBS), N, N-dicyclohexyl -2-benzothiazyl sulfenamide, N-oxydiethylene-2-benzothiazyl sulfenamide, N, N-diisopropyl-2-benzothiazole sulfenamide, and combinations thereof Based compound can be used.

Examples of the thiol-based vulcanization accelerator include 2-mercaptobenzothiazole (MBT), dibenzothiazyl disulfide (MBTS), sodium salt of 2-mercaptobenzothiazole, zinc salt of 2-mercaptobenzothiazole , A copper salt of 2-mercaptobenzothiazole, a cyclohexylamine salt of 2-mercaptobenzothiazole, 2- (2,4-dinitrophenyl) mercaptobenzothiazole, 2- Ethyl 4-morpholinothio) benzothiazole, and combinations thereof. The thiazole-based compound may be used alone or in combination of two or more thereof.

Examples of the thiuram-based vulcanization accelerator include tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide, tetramethylthiuram monosulfide, dipentamethylthiuram disulfide, dipentamethylthiuram monosulfide, dipentamethylene Any one of thiuram-based compounds selected from the group consisting of thiuram tetrasulfide, dipentamethylenethiuram hexasulfide, tetrabutylthiuram disulfide, pentamethylenethiuram tetrasulfide, and combinations thereof can be used.

Examples of the thiourea vulcanization accelerator include thiourea compounds selected from the group consisting of thiacarbamide, diethyl thiourea, dibutyl thiourea, trimethyl thiourea, diorthotolyl thiourea, and combinations thereof. Compounds may be used.

Examples of the guanidine-based vulcanization accelerator include guanidine-based compounds selected from the group consisting of diphenyl guanidine, diorthotolyl guanidine, triphenyl guanidine, orthotolyl biguanide, diphenyl guanidine phthalate, and combinations thereof .

Examples of the dithiocarbamate-based vulcanization accelerator include zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, Zinc dibutyldithiocarbamate, zinc diamidithiocarbamate, zinc dipropyldithiocarbamate, complexation of zinc with piperidinedithiocarbamate and piperidine, zinc hexadecylisopropyldithiocarbamate, octadecyl Isopropyl dithiocarbamic acid zinc zinc dibenzyldithiocarbamate, sodium diethyldithiocarbamate, penta methylenedithiocarbamate, sodium selenium dimethyldithiocarbamate, diethyldithiocarbamate, sodium diethyldithiocarbamate, Cadmium dithiocarbamate, and combinations thereof. The dithiocarbamic acid-based compound may be used alone or in combination of two or more thereof.

Examples of the aldehyde-amine type or aldehyde-ammonia type vulcanization accelerator include aldehyde selected from the group consisting of acetaldehyde-aniline reactant, butylaldehyde-aniline condensate, hexamethylenetetramine, acetaldehyde-ammonia reactant, -Amine-based or aldehyde-ammonia-based compounds may be used.

As the imidazoline-based vulcanization accelerator, for example, an imidazoline-based compound such as 2-mercaptoimidazoline can be used. Examples of the xanthate vulcanization accelerator include xanthates such as zinc dibutylxanthogenate Compounds may be used.

The vulcanization accelerator may be added in an amount of 0.5 to 2.5 parts by weight based on 100 parts by weight of the raw rubber in order to maximize productivity improvement and rubber property enhancement through vulcanization speed promotion.

The vulcanization accelerating assistant may be any one selected from the group consisting of an inorganic vulcanization accelerator aid, an organic vulcanization accelerator aid, and a combination thereof, which is used in combination with the vulcanization accelerator to complete the promoting effect thereof .

As the inorganic vulcanization accelerating aid, any one selected from the group consisting of zinc oxide (ZnO), zinc carbonate, magnesium oxide (MgO), lead oxide, potassium hydroxide and combinations thereof may be used have. As the organic vulcanization accelerating auxiliary, there may be selected from the group consisting of stearic acid, zinc stearate, palmitic acid, linoleic acid, oleic acid, lauric acid, dibutyl ammonium oleate, derivatives thereof, Can be used.

In particular, the zinc oxide and the stearic acid may be used together as the vulcanization accelerating assistant. In this case, the zinc oxide is dissolved in the stearic acid to form an effective complex with the vulcanization accelerator, Thereby facilitating the crosslinking reaction of the rubber.

When the zinc oxide and the stearic acid are used together, they may be used in an amount of 1 to 5 parts by weight and 0.5 to 3 parts by weight, respectively, based on 100 parts by weight of the raw rubber to serve as a proper vulcanization accelerator. If the content of the zinc oxide and the stearic acid is less than the above range, the vulcanization rate may be slow and the productivity may be deteriorated. If the content exceeds the above range, the scorch phenomenon may occur and the physical properties may be deteriorated.

The antioxidant is an additive used to stop the chain reaction in which the tire is autoxidized by oxygen. As the anti-aging agent, any one selected from the group consisting of an amine type, a phenol type, a quinoline type, an imidazole type, a carbamic acid metal salt, a wax and a combination thereof can be appropriately selected and used.

Examples of the amine type antioxidant include N-phenyl-N '- (1,3-dimethyl) -p-phenylenediamine, N- (1,3-dimethylbutyl) -N'- Phenyl-N'-isopropyl-p-phenylenediamine, N, N'-diphenyl-p-phenylenediamine, -Cyclohexyl p-phenylenediamine, N-phenyl-N'-octyl-p-phenylenediamine, and combinations thereof. Examples of the phenolic antioxidant include phenol-based 2,2'-methylene-bis (4-methyl-6-tert-butylphenol), 2,2'- isobutylidene- Di-t-butyl-p-cresol, and combinations thereof. As the quinoline antioxidant, 2,2,4-trimethyl-1,2-dihydroquinoline and its derivatives can be used. Specifically, 6-ethoxy-2,2,4-trimethyl- Dihydroquinoline, 6-anilino-2,2,4-trimethyl-1,2-dihydroquinoline, 6-dodecyl-2,2,4-trimethyl-1,2-dihydroquinoline and combinations thereof Any one selected from the group can be used. As the wax, waxy hydrocarbons can be preferably used.

Considering the conditions that the solubility of the antioxidant in addition to the anti-aging action is high, the solubility in the rubber is small, the volatility is small, the solubility should be inactive to the rubber, and the vulcanization should not be inhibited, By weight.

The rubber composition for a tire tread can be produced through a conventional two-step continuous manufacturing process. That is, during the finishing step in which a first step (referred to as a "non-production" step) of thermomechanical treatment or kneading at a maximum temperature of 110-190 ° C, preferably 130-180 ° C, and a crosslinking system are mixed, Can be prepared in a suitable mixer using a second stage (referred to as the "production" step) of mechanically treating at a low temperature, typically below 110 ° C, for example 40-100 ° C, but the invention is not so limited .

The rubber composition for a tire tread is not limited to a tread (a tread cap and a tread base) but may be included in various rubber components constituting the tire. Said rubber components include sidewalls, sidewall inserts, apex, chafer, wire coat or inner liner.

A tire according to another embodiment of the present invention is manufactured using the rubber composition for the tire tread. The method of manufacturing a tire using the rubber composition for a tire tread may be any method conventionally used for manufacturing a tire, and a detailed description thereof will be omitted herein.

The tires may be automobile tires, racing tires, airplane tires, agricultural tires, off-the-road tires, truck tires or bus tires. Also, the tire may be used as a radial tire or a bias tire.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[Production Example: Production of Rubber Composition]

Rubber compositions for tire treads according to the following Examples and Comparative Examples were prepared using the compositions shown in Table 1 below. The production of the rubber composition was in accordance with the usual production method of the rubber composition.

division Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Example 1 Raw rubber 100 100 100 100 100 Silica 120 120 120 120 120 Coupling agent 19 19 19 19 19 Conductive polymer 0 5 20 10 10 vegetable oil 0 0 0 0 10 Processing oil 10 10 10 10 0 Zinc oxide 3 3 3 3 3 Stearic acid One One One One One brimstone 1.5 1.5 1.5 1.5 1.5 accelerant 1.5 1.5 1.5 1.5 1.5

- Raw material rubber: solution polymerization A synthetic rubber consisting of 80% by weight of styrene butadiene rubber and 20% by weight of butadiene rubber

- Silica: silica having a CTAB adsorption value of 160 cm 2 / g and a nitrogen adsorption value of 175 cm 2 / g

- Conductive polymer: Poly (3-methyl-thiophene)

- Vegetable oil: soybean oil containing 50% by weight of linoleic acid, 20% by weight of oleic acid and the remaining amount of other fatty acids,

- Processed oils: Treaded Distillate Aromatic Extracts (TDAE)

- Accelerator: CBS (N-cyclohexyl-2-benzothiazoyl sulfonamide)

[Experimental Example: Measurement of Physical Properties of the Rubber Composition]

The physical properties of the rubber specimens prepared in Examples and Comparative Examples were measured and the results are shown in Table 2 below.

division Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Example 1 Mooney viscosity 73 75 86 80 74 Wear Index 100 99 95 97 100 Electrical resistance 1.58E + 08 1.26E + 08 1.41E + 07 3.98E + 07 3.98E + 07

- Mooney viscosity (ML1 + 4, 100 占 폚) was measured according to ASTM standard D1646. The Mooney viscosity is a value indicating the viscosity of the unvulcanized rubber. The lower the numerical value, the better the workability of the unvulcanized rubber.

The abrasion resistance index was indexed based on Comparative Example 1 using a rambone abrasion tester. The higher the wear resistance index, the better the wear resistance.

- Electrical resistivity showed the minimum resistance measured under conditions of relative humidity 50% and temperature 23 ℃.

Referring to Table 2, it can be seen that the electrical resistances of Comparative Examples 2 to 4 and Example 1 including the conductive polymer are improved compared to Comparative Example 1, which does not include the conductive polymer. The electrical resistance performance was excellent when the conductive polymer was contained in an amount of 10 parts by weight.

However, in Comparative Examples 2 to 4, the electrical resistance was improved, but the viscosity was increased and the workability and wear resistance performance were lowered.

On the other hand, Example 1 using the vegetable oil instead of the processing oil showed not only an improvement in electrical resistance but also a Mooney viscosity and an abrasion resistance as in Comparative Example 1 or higher. From this, it can be seen that when the conductive polymer and the vegetable oil are used at the same time, the electric conductivity, the dispersion stability, and the wear resistance can be improved according to the embodiment of the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of the right.

Claims (7)

100 parts by weight of the raw rubber,
60 to 130 parts by weight of silica,
5 to 20 parts by weight of a conductive polymer, and
5 to 20 parts by weight of vegetable oil
And a rubber composition for a tire tread. The method according to claim 1,
The conductive polymer may be at least one selected from the group consisting of poly (3-alkyl-thiophene), polyacetylene, polyaniline, polythiophene, Poly (1,4-phenylenevinylene), poly (1,4-phenylenesulfide), poly (fluorenyleneethynylene) And mixtures thereof. ≪ Desc / Clms Page number 24 > The method according to claim 1,
Wherein the conductive polymer is represented by the following general formula (1).
≪ Formula 1 >

(n is a natural number of 5 to 50,000,
R is any one selected from the group consisting of an alkyl group having 2 to 20 carbon atoms, an alkoxy group having 2 to 20 carbon atoms, an alkylene alkoxy group having 2 to 20 carbon atoms, and a polyalkylene oxide group having 2 to 20 carbon atoms. The method according to claim 1,
Wherein the vegetable oil is any one selected from the group consisting of soybean oil, sunflower oil, canola oil, grape seed oil, and mixtures thereof. The method according to claim 1,
Wherein the vegetable oil is soybean oil containing 40 to 60% by weight of linoleic acid, 10 to 30% by weight of oleic acid and the remaining amount of fatty acids other than the two, The method according to claim 1,
The rubber composition for a tire tread according to claim 1, wherein 1.5 to 2.5 parts by weight of a vulcanizing agent, 0.5 to 2.5 parts by weight of a vulcanization accelerator, 1 to 5 parts by weight of zinc oxide, 0.5 to 3 parts by weight of stearic acid, 1 to 10 parts by weight of a rubber composition for a tire tread. A tire produced by using the rubber composition for a tire tread according to any one of claims 1 to 6.