KR101383089B1 - Rubber composition for tire tread and tire manufactured by using the same - Google Patents

Abstract

(상기 화학식1의 PA, PE 및 n은 발명의 상세한 설명에 기재된 바에 의한다.)The present invention relates to a rubber composition for tire treads and a tire manufactured using the same. The rubber composition for tire treads of the present invention includes silica and a copolymer represented by the following Chemical Formula 1. The tire tread rubber composition may improve braking performance of a wet road surface without deteriorating low fuel consumption performance and wear performance.
[Chemical Formula 1]

(PA, PE and n in Formula 1 are as described in the detailed description of the invention.)

Description

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

The present invention relates to a rubber composition for tire treads and a tire manufactured using the same, and to a rubber tread rubber composition having excellent wet road surface braking performance without deterioration in low fuel consumption performance and wear performance, and a tire manufactured using the same.

Recently, in Europe and Japan, a label notation system for tire performance has been introduced, and consumers' interest in tire performance has increased, and the performance required by consumers has been diversified.

Among the major performances of tires, it is necessary to satisfy various performances at the same time in order to cope with the labeling system introduced in Europe, in particular, and the importance of wet road braking performance and low fuel consumption performance is highlighted.

In general, wet road braking performance, low fuel consumption performance and wear characteristics are called Magic Triangle in tire technology, and if one performance is to be superior, the other tends to show trade-off characteristics that degrade. . Specifically, when the tire wear performance and fuel economy performance are improved, the braking performance may be rather deteriorated, and when the tire braking performance is improved, the fuel efficiency may be disadvantageous or the wear performance may be deteriorated.

As each performance of a tire is improved when one performance is improved, the other performance is degraded, that is, a conflicting characteristic is required. Therefore, it is necessary to develop a technology that can improve one performance and minimize the other performance degradation. have.

KR 10-0856870 B

SUMMARY OF THE INVENTION An object of the present invention is to provide a rubber tread rubber composition in which wet road surface braking performance is improved by adding silica and poly (ether-amide) copolymers without deteriorating wear resistance and low fuel consumption performance.

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

In order to achieve the above object, the rubber composition for a tire tread according to an embodiment of the present invention comprises a silica and a copolymer represented by the following formula (1).

[Chemical Formula 1]

(2)

(3)

In Formula 1, PA is a repeating unit represented by Formula 2, PE is a repeating unit represented by Formula 3, and n is an integer of 2 to 10. In Formulas 2 and 3, R ₁ to R ₄ are each independently a group consisting of alkylene having 1 to 30 carbon atoms, cycloalkylene having 1 to 30 carbon atoms, arylene having 6 to 30 carbon atoms, and heteroarylene having 2 to 30 carbon atoms. Any one selected from, l is an integer of 20 to 60, m is an integer of 15 to 45.

The tire tread rubber composition may include 100 parts by weight of raw material rubber including 70 to 90 parts by weight of solution-polymerized styrene-butadiene rubber and 10 to 30 parts by weight of butadiene rubber, and 3 to 10 parts by weight of the copolymer represented by Chemical Formula 1. Can be.

The copolymer represented by Formula 1 may have a weight average molecular weight of 10,000 to 100,000 g / mol.

The silica may be included in 20 to 90 parts by weight based on 100 parts by weight of the raw material rubber, the nitrogen adsorption specific surface area may be 150 to 230 m 2 / g and CTAB value of 150 to 230 m 2 / g.

The tire tread rubber composition may further include a softener in an amount of 20 to 35 parts by weight based on 100 parts by weight of the raw material rubber.

The tire tread rubber composition further includes 6 to 10 parts by weight of coupling agent, 1.0 to 1.5 parts by weight of vulcanizing agent, 1.0 to 3.5 parts by weight of vulcanization accelerator, and 2.0 to 3.0 parts by weight of anti-aging agent based on 100 parts by weight of the raw material rubber. It may be.

A tire according to another embodiment of the present invention is manufactured using the rubber composition for a tire tread.

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

The definitions of the terms used in this specification are as follows.

Unless stated otherwise in the present specification, arylene means a divalent atom group obtained by subtracting two hydrogen atoms from arenes, and the arene includes not only one benzene ring but also two to seven. Hydrocarbons, including dogs, and derivatives thereof.

Unless stated otherwise in the present specification, the prefix hetero means that one to three heteroatoms selected from the group consisting of -N-, -O-, -S-, and -P- replace a carbon atom. For example, a heteroalkyl group means that the said hetero atom substitutes 1-3 carbon atoms in the carbon atom of an alkyl group.

A polyalkylene (alkylene) unless otherwise specified in this specification is a divalent atomic group obtained by subtracting two hydrogen atoms from an alkane (alkane), the general formula -C _n H _2n - may be displayed. The alkane includes a linear alkane and a branched alkane, and includes a primary alkane, a secondary alkane, and a tertiary alkane.

Cycloalkylene is a divalent atom group minus two hydrogen atoms in cycloalkane unless otherwise specified herein. The cycloalkane includes monocyclic, bicyclic, tricyclic and tetracyclic. Moreover, the polycyclic cycloalkyl group containing an adamantyl group and a norbornyl group is included.

In the present specification, all the compounds or substituents may be substituted or unsubstituted unless otherwise specified. Herein, substituted hydrogen is a halogen atom, a hydroxy group, a carboxy group, a cyano group, a nitro group, an amino group, a thio group, a methyl thio group, an alkoxy group, a nitrile group, an aldehyde group, an epoxy group, an ether group, an ester group, an ester group, A carbonyl group, an acetal group, a ketone group, an alkyl group, a cycloalkyl group, a heterocycloalkyl group, a benzyl group, an aryl group, a heteroaryl group, a perfluoroalkaline group, a derivative thereof, and a combination thereof, and ones substituted by any one of them it means.

The rubber composition for tire treads according to an embodiment of the present invention includes silica and a copolymer represented by Chemical Formula 1 below.

[Chemical Formula 1]

In Formula 1, PA is a repeating unit represented by Formula 2, PE is a repeating unit represented by Formula 3, and n is an integer of 2 to 10.

(2)

(3)

The weight average molecular weight of polyamide (PA) represented by Formula 2 may be 2.000 to 50.000 g / mol, R ₁ and R ₂ may be each independently alkyl or aromatic, preferably each independently C 1 to C It is any one selected from the group consisting of 30 alkylene cycloalkylene having 1 to 30 carbon atoms, arylene having 6 to 30 carbon atoms and heteroarylene having 2 to 30 carbon atoms, wherein l may be an integer of 20 to 60.

The weight average molecular weight of the polyether (PE) represented by Formula 3 may be 5,000 to 50,000 g / mol, R ₃ to R ₄ may be each independently alkyl or aromatic, preferably each independently 1 to C It is any one selected from the group consisting of 30 alkylene cycloalkylene having 1 to 30 carbon atoms, arylene having 6 to 30 carbon atoms and heteroarylene having 2 to 30 carbon atoms, m may be an integer of 15 to 45.

The tire tread rubber composition may further include raw rubber, and the copolymer represented by Chemical Formula 1 may be included in an amount of 3 to 10 parts by weight, preferably 7 to 10 parts by weight, based on 100 parts by weight of the raw material rubber. If the content is less than 3 parts by weight, the braking performance is insignificant on the wet road surface, and if it exceeds 10 parts by weight, there may be a problem of lowering the overall physical properties of the compounded rubber. It is desirable to improve the physical properties of the rubber by improving the affinity of the filler and the raw material rubber to improve the mixing, dispersibility and processability of the other additives.

The weight average molecular weight of the copolymer represented by the formula (1) may be 10,000 to 100,000 g / mol, when using the copolymer represented by the formula (1) having a weight average molecular weight in the above range to the braking performance of the tire May be advantageous.

The raw material rubber may be any one selected from the group consisting of natural rubber, synthetic rubber, and combinations thereof.

The natural rubber may be a general natural rubber or a modified natural rubber.

The above-mentioned general natural rubber may be used as long as it is known as natural rubber, and the country of origin and the like are not limited. 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 general natural rubber is modified or purified. For example, examples of the modified natural rubber include epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber.

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, chlorosulfonated polyethylene rubber, epichlorohydrin rubber, fluorine rubber, silicone rubber, Butadiene rubber, nitrile rubber, nitrile butadiene rubber (NBR), modified nitrile butadiene rubber, chlorinated polyethylene rubber, styrene ethylene butylene styrene (SEBS) rubber, ethylene propylene rubber, ethylene propylene diene (EPDM) rubber, Ethylene vinyl acetate rubber, acrylic rubber, hydrin rubber, vinyl benzyl chloride styrene butadiene rubber, bromomethyl styrene butyl rubber, maleic styrene butadiene rubber, carboxylic styrene butadiene rubber, epoxy isoprene rubber, ethylene propylene rubber maleic acid, Nitrile butadiene rubber It may be a p-methyl styrene (brominated polyisobutyl isoprene-co-paramethyl styrene, BIMS), and one selected from the group consisting of -, bromo mineyi suited polyisobutyl isoprene-co.

In particular, the raw material rubber is composed of a solution-polymerized Styrene Butadiene rubber (hereinafter referred to as 'S-SBR'), butadiene rubber (hereinafter referred to as 'BR') and combinations thereof Any one selected from the group can be preferably used.

The BR may be a high cis-butadiene rubber having a cis 1,4-butadiene content of 95% by weight or more and a glass transition temperature (Tg) of −107 to −104 ° C., preferably glass It may be a high cis butadiene rubber having a transition temperature (Tg) of -106 to -105 ° C. The BR may have a Mooney viscosity of 43 to 47 at 100 ° C. In the case of using the BR, there is an advantageous effect in terms of abrasion resistance performance and heat build up under dynamic stress.

The S-SBR is a kind of synthetic rubber obtained by copolymerization of styrene and butadiene, specifically 20 to 40% by weight of styrene, 40 to 65% by weight of vinyl contained in butadiene, number average molecular weight (Mn) 100,000 to 400,000 g / mol, weight average molecular weight (Mw) of 600,000 to 1,200,000 g / mol, molecular weight distribution (MWD) of 2.5 to 4.2 and glass transition temperature (Tg) of -27 to -18 ° C. It is possible to use, preferably -25 to -20 ℃. When the S-SBR having the above characteristics is used, the hysteresis of the tire tread is increased, thereby improving braking performance on wet surfaces. In order to improve wet road braking performance, it is preferable to use S-SBR having a relatively high glass transition temperature.

In addition, the S-SBR may contain 25 to 50 parts by weight of TDAE oil, preferably 25 to 40 parts by weight, per 100 parts by weight of the original rubber elastomer. When the S-SBR contains 25 to 50 parts by weight of TDAE oil per 100 parts by weight of the rubbery elastomer, it is preferable in view of the increased flexibility of S-SBR, which may be reduced by the influence of styrene.

In addition, the raw material rubber comprises 70 to 90 parts by weight of rubber S-SBR and 10 to 30 parts by weight of BR, preferably S-SBR comprises 70 to 85 parts by weight and BR to 15 to 30 parts by weight, and more Preferably it may comprise 75 to 85 parts by weight of S-SBR and 15 to 25 parts by weight of BR. When the content of BR exceeds 30 parts by weight, the braking performance may be reduced, and when the content of BR is less than 10 parts by weight, wear resistance may be reduced. In addition, when the content of the S-SBR is less than 70 parts by weight, the braking performance may be reduced, and when it exceeds 90 parts by weight, the wear resistance may be reduced.

The silica may have a nitrogen surface area per gram (N ₂ SA) of 150 to 230 m 2 / g and a CTAB (cetyl trimethyl ammonium bromide) value of 150 to 230 m 2 / g.

When the nitrogen adsorption specific surface area of the silica is less than 150 m 2 / g, reinforcing performance by silica as a filler may be detrimental, and when it exceeds 230 m 2 / g, the workability of the rubber composition may be deteriorated. In addition, when the CTAB value of the silica is less than 150 m 2 / g, the reinforcing performance by the filler silica may be detrimental, and when it exceeds 230 m 2 / g may be disadvantageous processability of the rubber composition.

Ultrasil VN2 (manufactured by Degussa AG), Ultrasil VN3 (manufactured by Degussa AG), Z1165MP (manufactured by Rhodia) or Z165GR (manufactured by Rhodia) can be used as the commercially available products. .

The silica may be included in 20 to 90 parts by weight based on 100 parts by weight of the raw material rubber, it is preferably included in 25 to 85 parts by weight. If the content of the silica is less than 20 parts by weight, the strength of the rubber may not be improved and the braking performance of the tire may be deteriorated. If the content of the silica exceeds 90 parts by weight, the wear performance may be deteriorated.

The tire tread rubber composition may optionally further include various additives such as additional vulcanizing agents, vulcanization accelerators, vulcanization accelerators, coupling agents, anti-aging agents, processing aids or softeners. 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, a sulfur vulcanizing agent can be preferably used. The sulfur vulcanizing agent may be an inorganic vulcanizing agent such as powdered sulfur (S), insoluble sulfur (S), precipitated sulfur (S), or colloid sulfur. 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 vulcanizing agent may be included in an amount of 0.5 to 4.0 parts by weight based on 100 parts by weight of the raw material rubber. Preferably, the vulcanizing agent is included in an amount of 1.0 to 1.5 parts by weight so that the raw material rubber is less sensitive to heat and chemically stable. Preferred at

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, dithiocarbamic acid, aldehyde-amine, aldehyde-ammonia, imidazoline, xanthate and their Any one selected from the group consisting of combinations can be used, and sulfenamide-based and guanidine-based vulcanization accelerators can be preferably used.

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.

As the guanidine-based vulcanization accelerator, for example, any one guanidine-based compound selected from the group consisting of diphenylguanidine, diorthotolylguanidine, triphenylguanidine, orthotolylbiguanide, diphenylguanidine phthalate, and combinations thereof can be used. It is possible to use, preferably diphenylguanidine.

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 included in an amount of 0.5 to 4.0 parts by weight, preferably 1.0 to 3.5 parts by weight, based on 100 parts by weight of the raw material rubber in order to maximize productivity and rubber properties by promoting the vulcanization rate.

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, the zinc oxide may be used in an amount of 1.0 to 5.0 parts by weight and 0.5 to 3.0 parts by weight with respect to 100 parts by weight of the raw material rubber, respectively, as a suitable 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.

Examples of the coupling agent include a sulfide-based silane compound, a mercapto-based silane compound, a vinyl-based silane compound, an amino-based silane compound, a glycidoxine clock silane compound, a nitro- based silane compound, a chlorosilicate compound, a methacrylic silane compound, May be used, and a sulfide-based silane compound may be preferably used.

The sulfide-based silane compound is preferably selected from the group consisting of bis (3-triethoxysilylpropyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, bis (4-trimethoxysilylbutyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis Bis (3-trimethoxysilylethyl) trisulfide, bis (4-triethoxysilylethyl) trisulfide, bis (4-trimethoxysilylbutyl) trisulfide, bis (3-triethoxysilylbutyl) disulfide, bis (4-triethoxysilylbutyl) disulfide, bis 3-trimethoxysilylpropyl) disulfide, bis (2-trimethoxy Triethoxysilylbutyl) disulfide, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N, N-dimethyl 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyltetrasulfide, 2-trimethoxysilylethyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-trimethoxysilyl 3-trimethoxysilylpropylmethacrylate monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, and combinations thereof may be used in combination with at least one compound selected from the group consisting of benzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, And the like. Preferably bis (3-triethoxysilylpropyl) tetrasulfide.

The mercaptosilane compound may be at least one selected from the group consisting of 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, May be any one selected from the group consisting of The vinyl-based silane compound may be any one selected from the group consisting of ethoxysilane, vinyltrimethoxysilane, and combinations thereof. The amino-based silane compound is preferably selected from the group consisting of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropyltriethoxysilane, 3- Methoxysilane, and a combination thereof.

The glycidoxime silane compound is preferably selected from the group consisting of? -Glycidoxypropyltriethoxysilane,? -Glycidoxypropyltrimethoxysilane,? -Glycidoxypropylmethyldiethoxysilane,? -Glycidoxypropylmethyldimethoxysilane And a combination thereof. The nitro-based silane compound may be any one selected from the group consisting of 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, and combinations thereof. The chloro-based silane compound is selected from the group consisting of 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 2-chloroethyltrimethoxysilane, 2-chloroethyltriethoxysilane, and combinations thereof Lt; / RTI >

The methacrylic silane compound may be any one selected from the group consisting of? -Methacryloxypropyltrimethoxysilane,? -Methacryloxypropylmethyldimethoxysilane,? -Methacryloxypropyldimethylmethoxysilane, and combinations thereof Lt; / RTI >

The coupling agent may be included in an amount of 1 to 20 parts by weight based on 100 parts by weight of the raw rubber for improving dispersibility of the silica. When the content of the coupling agent is less than 1 part by weight, the improvement of dispersibility of silica may be insufficient, and the workability of the rubber may be reduced or the low fuel consumption performance may be reduced. In addition, an excessive coupling reaction with the rubber may occur to increase the interaction with the rubber, thereby resulting in low fuel efficiency but excellent braking performance and workability.

When using a silane compound as a coupling agent, the hydrophilic group, which is a hydrophilic group on the surface of silica, and its derivatives may be hydrophilized through physical or chemical reactions to induce a chemical bond between rubber and silica, thereby improving silica dispersibility. have.

The processing aid is added to the rubber composition in order to facilitate the mixing of the rubber, to prevent adhesion of the short-barrier mixer, and to uniformly mix the rubber. As the processing aid, any one selected from the group consisting of saturated fatty acids, unsaturated fatty acids, metal salts, and combinations thereof may be used.

The processing aid may include 1 to 5 parts by weight based on 100 parts by weight of the raw rubber to improve the processability of the rubber. When the processing aid is less than 1 part by weight, the effect may be insignificant, and when the processing aid is more than 5 parts by weight, the physical properties of the compounded rubber may be reduced.

The softener is added to the rubber composition to impart plasticity to the rubber to facilitate processing, or to lower the hardness of the vulcanized rubber, and refers to oils and other materials used in rubber compounding or rubber production. The softening agent means an oil contained in a process oil or other rubber composition. The softener may be selected from the group consisting of petroleum oils, vegetable oils, and combinations thereof, but the present invention is not limited thereto.

The petroleum-based oil may be selected from the group consisting of paraffinic oil, naphthenic oil, aromatic oil, and combinations thereof.

Examples of the paraffin oil include P-1, P-2, P-3, P-4, P-5 and P-6 of Mychang Oil Co., N-1, N-2 and N-3 of Kokai Co., Ltd., and representative examples of the aromatic oils include A-2 and A-3 of Mingchang Oil Co.,

However, with the recent increase in environmental awareness, when the content of polycyclic aromatic hydrocarbons (hereinafter referred to as PAHs) contained in the aromatic oil is 3% by weight or more, it is known that cancer is likely to occur. Treated distillate aromatic extract oil, mild extraction solvate oil, residual aromatic extract oil or heavy naphthenic oil can be preferably used.

Particularly, the oil used as the softening agent preferably has a total content of PAHs components of not more than 3 wt%, a kinematic viscosity of not less than 95 (210 S SUS), an aromatic component of 15 to 25 wt%, a naphthene component Of 27 to 37% by weight and a paraffinic component of 38 to 58% by weight can be preferably used.

The TDAE oil is advantageous for environmental factors such as the low temperature characteristics of the tire tread including the TDAE oil and the possibility of the cancer induction of PAHs while improving the fuel consumption performance.

Examples of the vegetable oils include vegetable oils such as castor oil, cottonseed oil, linseed oil, canola oil, soybean oil, palm oil, palm oil, peanut oil, pine oil, pine tar, tall oil, cone oil, rice bran oil, safflower oil, sesame oil, , Jojoba oil, macadamia nut oil, four flower oil, tung oil, and combinations thereof.

The softener may be used in an amount of 0 to 150 parts by weight based on 100 parts by weight of the raw material rubber, and preferably 20 to 35 parts by weight of the TDAE oil improves the processability of the raw material rubber.

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 amine-based, phenol-based, quinoline-based, imidazole-based, carbamic acid metal salts, waxes and combinations thereof may be appropriately selected, and preferably amine-based aging. An inhibitor can be used.

Examples of the amine antioxidant include N-phenyl-N '-(1,3-dimethyl) -p-phenylenediamine, N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine, N-phenyl-N'-isopropyl-p-phenylenediamine, N, N'-diphenyl-p-phenylenediamine, N, N'-diaryl-p-phenylenediamine, N-phenyl-N ' Any one selected from the group consisting of -cyclohexyl p-phenylenediamine, N-phenyl-N'-octyl-p-phenylenediamine, and combinations thereof, Preferably, N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine can be used.

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.

The anti-aging agent has a high solubility in rubber in addition to the anti-aging action, is low in volatility, inert to rubber, and does not inhibit vulcanization. It may be included in parts by weight, preferably from 2.0 to 3.0 parts 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 the first stage of thermomechanical treatment or kneading and the crosslinking system are mixed at a maximum temperature of 110 to 190 占 폚, preferably at a high temperature of 130 to 180 占 폚, typically less than 110 占 폚, And a second step of mechanical treatment at a low temperature of 40 to 100 DEG C in a suitable mixer, but the present invention is not limited thereto.

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. Further, the tire may be a radial tire or a bias tire, and preferably a radial tire.

By using the rubber tread rubber composition according to the present invention, it is possible to manufacture a tire with improved braking performance on a wet road without a significant reduction in low fuel efficiency and wear performance, thereby ensuring both efficiency and safety of fuel economy through a functional 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.

[ Manufacturing example : Preparation 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.

(Unit: parts by weight) Comparative Example Example 1 Example 2 Example 3 Example 4 S-SBR ^{1 )} 75 75 75 75 75 BR ^{2 )} 25 25 25 25 25 Silica ^{3 )} 80 80 80 80 80 Coupling Agents ^{4 )} 8 8 8 8 8 Copolymer ^{5 )} - 3 5 7 10 Processing aid ^{6 )} 4 4 - - - Softener ^{7 )} 26 26 24 22 20 Zinc oxide 3 3 3 3 3 Stearic acid One One One One One Antioxidant (6C) ^{8 )} 2.5 2.5 2.5 2.5 2.5 DPG ^{9 )} 1.5 1.5 1.5 1.5 1.5 Vulcanizing agent (sulfur) 1.1 1.1 1.4 1.4 1.4 CBS ^{10 )} 2 2 2 2 2

1) S-SBR: styrene-butadiene rubber with glass transition temperature (Tg) -25 to 20 ° C, styrene content 25% by weight and vinyl content 63% by weight of butadiene

2) BR: glass cis-butadiene rubber having a glass transition temperature (Tg) of -106 ° C and a cis 1,4-butadiene content of 95% by weight or more

3) Silica: Ultra 7000Gr (Degussa AG), nitrogen adsorption specific surface area 170㎡ / g, CTAB value 160㎡ / g

4) Coupling agents: TESPT, Si69 (Degussa), bis (3triethoxysilylpropyl) tetrasulfide

5) Copolymer: In Formula 1, n is about 5 and the weight average molecular weight is 10,000 to 100,000 g / mol,

In Formula 2, R ₁ is-(CH ₂ ) _6- , R ₂ is-(CH ₂ ) _4- , l is about 45,

In formula (3), R ₃ is -CH (CH ₃ ) CH _2- , R ₄ is -CH (CH ₃ ) CH (CH ₃ )-and m is about 30. Copolymer of polyamide and polyether.

6) Processing aid: struktol A60

7) Softener: TDAE Oil

8) Antioxidant (6C): N-1,3-dimethylbutyl-N-phenyl-p-phenylenediamine

9) DPG: Diphenylenguanidine

10) CBS: N-cyclohexyl-2-benzothiazylsulfenamide

 [ Experimental Example : Measurement of physical properties of the prepared rubber composition]

The physical properties of the rubber specimens of each of Examples and Comparative Examples having the content ratios of Table 1 were measured and shown in Table 2.

The following 300% Modulus (Modulus) is the tensile strength at 300% elongation, measured according to the ISO 37 standard, the higher the value shows excellent strength.

The 300% modulus uses a dumbbell-type rubber specimen of length 100mm, width 25mm, and width 5mm, to stress the 300% elongation from the initial strain from the strain-stress curve when the specimen is stretched by 20mm in length and 5mm in width. Measured.

The wear index shown below is the Lambon abrasion tester ratio, which is the value of the loss of rubber worn by rotating at a sliding ratio of 25% and a load of 1.5 kg at room temperature. The higher the value, the better the wear performance. .

* Wear Index = (wear amount of comparative example / wear amount of example) × 100

0 ° C Tan δ is a measure of wet road braking performance, which means that the higher the value, the better. 60 ° C Tan δ is a measure of rotational resistance at 60 ° C.

Comparative Example Example 1 Example 2 Example 3 Example 4 300% Modulus (kgf / ㎠) 110 107 109 113 115 Wear index 100 101 99 99 102 0 C Tan δ 0.295 0.305 0.311 0.314 0.317 60 캜 Tan δ 0.145 0.142 0.141 0.139 0.143

Referring to Table 2 above, in the case of Examples 1 to 4 including the copolymer, although the wet road surface braking performance and the low fuel consumption performance were both improved compared to those of the rubber of Comparative Example 1 not including the same, the wear performance was almost in the numerical range of deviation. It was confirmed that it remained without change. In addition, 300% modulus was slightly decreased in Examples 1 and 2 with respect to tensile strength, but in Examples 3 and 4, the performance was improved.

In particular, when looking at the 0 ° C and 60 ° C Tan δ values showing wet road braking performance and low fuel consumption characteristics, it was confirmed that the wet road surface braking performance and low fuel consumption characteristics were improved in all of Examples 1 to 4, the copolymer. It was confirmed that it is effective to improve the wet road surface braking performance and low fuel consumption characteristics. In particular, the wet road surface braking performance was excellent in Example 4, but the low fuel consumption performance was lower than that of Example 3, and the rubber composition of Example 3, which was excellent in both wet road braking performance and low fuel consumption performance, showed the most desirable physical properties.

These results indicate that the low fuel consumption performance, wet road surface braking performance and abrasion performance are conflicting characteristics. Considering that it is difficult to improve only one of the characteristics without improving it can be seen that the improved physical properties of the embodiment is a remarkably excellent effect.

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 (8)

A rubber composition for tire treads comprising silica and a copolymer represented by the following formula (1).
[Chemical Formula 1]

(In the above formula 1
The PA is a repeating unit represented by the following formula (2),
The PE is a repeating unit represented by the following formula (3),
N is an integer of 2 to 10,
(2)

(3)

In Chemical Formulas 2 and 3,
R ₁ to R ₄ are each independently selected from the group consisting of alkylene having 1 to 30 carbon atoms cycloalkylene having 1 to 30 carbon atoms, allylene having 6 to 30 carbon atoms and heteroarylene having 2 to 30 carbon atoms. ego,
L is an integer of 20 to 60,
M is an integer from 15 to 45) The method of claim 1,
The tire tread rubber composition includes 100 parts by weight of raw material rubber including 70 to 90 parts by weight of solution-polymerized styrene-butadiene rubber and 10 to 30 parts by weight of butadiene rubber, and 3 to 10 parts by weight of the copolymer represented by Chemical Formula 1. The rubber composition for tire tread. The method of claim 1,
The copolymer represented by the formula (1) is a tire tread rubber composition having a weight average molecular weight of 10,000 to 100,000 g / mol. 3. The method of claim 2,
The silica is a rubber composition for tire tread that is contained in 20 to 90 parts by weight based on 100 parts by weight of the raw material rubber. 5. The method of claim 4,
The silica has a nitrogen adsorption specific surface area of 150 to 230 m 2 / g, CTAB value of 150 to 230 m 2 / g rubber composition for the tire tread. 3. The method of claim 2,
The tire tread rubber composition further comprises 20 to 35 parts by weight of a softener based on 100 parts by weight of the raw material rubber. 3. The method of claim 2,
The tire tread rubber composition is based on 100 parts by weight of the raw material rubber
6.0-10.0 parts by weight of coupling agent,
1.0 to 1.5 parts by weight of vulcanizing agent,
1.0 to 3.5 parts by weight of vulcanization accelerator, and
Antioxidant 2.0 to 3.0 parts by weight
The rubber composition for a tire tread further comprising. A tire manufactured using the rubber composition for tire tread according to any one of claims 1 to 7.