KR20230049474A - Method of tire rubber composition, Tire tread rubber composition made by the method and Tire comprising the tire tread rubber composition - Google Patents

Abstract

One aspect of the present invention is to provide a method for preparing a tire rubber composition, which increases the dispersibility of the tire rubber composition. To this end, disclosed is a method of preparing a tire rubber composition, comprising a first step of mixing 100 parts by weight of raw rubber, 90 to 140 parts by weight of filler (based on 100 parts by weight of the raw rubber), and 0.01 to 0.2 parts by weight of a vulcanizing agent (based on 100 parts by weight of the raw rubber); and a second step of mixing 1.8 to 9.99 parts by weight of a vulcanizing agent (based on 100 parts by weight of the raw rubber) and 0.5 to 4.0 parts by weight of a vulcanization accelerator (based on 100 parts by weight of the raw rubber) with the result of the first step.

Description

Method of producing a tire rubber composition, a tire tread rubber composition prepared therefrom, and a tire comprising the same

It relates to a method for preparing a tire rubber composition, a tire tread rubber composition prepared therefrom, and a tire comprising the same.

An automobile tire supports a heavy load and is a high-speed rotating object. The tread, which has the greatest influence on the durability of the tire, has a great influence on the driving performance of the tire because it is in contact with the ground.

As the characteristics that tire tread rubber should have, there are steering stability, riding comfort, fuel efficiency, snow performance, abrasion resistance, braking performance, and durability.

A tire rubber composition is prepared by mixing raw rubber, filler, various chemicals, sulfur, and the like, and a tire is produced by heating the mixed rubber composition at a high temperature.

The tire rubber composition shows good physical properties of the resulting tire when it is heated in a state in which the raw material rubber, filler, various chemicals, and sulfur are well dispersed throughout the composition.

If the raw rubber, filler, various chemicals, and sulfur included in the tire rubber composition are not well dispersed throughout the composition, for example, the filler is present in a higher density in one part or the sulfur is more in another part. When a product is completed by being heated in a state of high density, it may have a fatal effect on the performance of a high-speed rotating tire.

One aspect is to provide a method for preparing a tire rubber composition that increases the dispersibility of the tire rubber composition.

Another aspect is to provide a tire tread rubber composition prepared by the tire rubber composition manufacturing method.

Another aspect is to provide a tire made of the tire tread rubber composition.

According to one aspect,

A first step of mixing 100 parts by weight of raw rubber, 90 to 140 parts by weight of filler (based on 100 parts by weight of the raw rubber) and 0.01 to 0.2 parts by weight of a vulcanizing agent (based on 100 parts by weight of the raw rubber); and

A second step of mixing 1.8 to 9.99 parts by weight of a vulcanization agent (based on 100 parts by weight of the raw rubber) and 0.5 to 4.0 parts by weight of a vulcanization accelerator (based on 100 parts by weight of the raw rubber) with the product of the first step; A method for producing a tire rubber composition is provided.

According to another aspect,

A tire tread rubber composition prepared by the above tire rubber composition manufacturing method is provided.

According to another aspect,

A tire made of the tire tread rubber composition is provided.

The tire rubber composition prepared by the method for preparing a tire rubber composition according to an embodiment of the present invention has good processability, excellent dispersibility, and an appropriate scorch time and an appropriate vulcanization time.

Therefore, in the case of rubber with low productivity due to poor mixing processability, it is possible to improve the processability of the unvulcanized tire rubber composition by adding sulfur separately without significantly changing the recipe.

1 is a diagram schematically showing the structure of a tire according to one embodiment.
2 is a photograph showing a comparison of processability in a first step in Examples and Comparative Examples of a method for manufacturing a tire rubber composition according to an embodiment.

Hereinafter, a method for manufacturing a tire rubber composition according to an exemplary embodiment, a tire tread rubber composition prepared therefrom, and a tire including the same will be described in more detail.

Since the inventive idea disclosed in this specification can be subjected to various transformations and can have various implementations, specific implementations are described in detail in the detailed description and, if necessary, specific implementations are illustrated in the drawings. Effects and characteristics of the inventive idea of the present specification, and methods for achieving them will become clear with reference to implementations described later in detail together with the drawings. However, the creative idea of the present specification is not limited to the embodiments disclosed below and may be implemented in various forms.

In the following embodiments, terms such as first and second are used for the purpose of distinguishing one component from another, not in a limiting sense.

In the following embodiments, singular expressions include plural expressions unless the context clearly dictates otherwise.

In the following embodiments, terms such as include or have mean that features or elements described in the specification exist, and do not preclude the possibility that one or more other features or elements may be added.

In case an embodiment is otherwise embodied, a specific process sequence may be performed differently from the described sequence. For example, two processes described in succession may be performed substantially simultaneously, or may be performed in an order reverse to the order described.

Hereinafter, if necessary, embodiments of the present invention will be described in detail with reference to the accompanying drawings. do it with

In the drawings, the size of components may be exaggerated or reduced for convenience of description. For example, since the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of explanation, the inventive ideas disclosed herein are not necessarily limited to those shown.

Recently, high-performance tires such as fuel efficiency, braking, and stability are required.

When the rolling resistance is reduced, the elasticity of the tread rubber must be increased, and accordingly, a rubber composition requiring excellent physical properties is required.

However, since the physical properties and processability of rubber are mostly inversely proportional, rubber recipe changes occur due to processability problems during mixing, and losses and dispersion deviations occur due to frequent process troubles, resulting in problems in tire performance reproducibility. Therefore, there is a limit to simultaneously satisfying both the manufacturing of high-performance tires and the improvement of rubber processability.

A method for manufacturing a tire rubber composition according to an embodiment includes 100 parts by weight of raw rubber, 90 to 140 parts by weight of a filler (based on 100 parts by weight of the raw rubber), and 0.01 to 0.2 parts by weight of a vulcanizing agent (based on 100 parts by weight of the raw rubber). The first step of mixing; and

A second step of mixing 1.8 to 9.99 parts by weight of a vulcanization agent (based on 100 parts by weight of the raw rubber) and 0.5 to 4.0 parts by weight of a vulcanization accelerator (based on 100 parts by weight of the raw rubber) with the product of the first step; can do.

In the method for manufacturing a tire rubber composition according to an embodiment of the present invention, when mixing the rubber composition, a vulcanizing agent (eg, sulfur) is dividedly injected in each step to induce minimum cross-liking, thereby improving processability and dispersion during mixing. was able to improve tire performance, quality and fairness.

The first step may be performed at a temperature of 110 to 190 °C, for example, 135 to 160 °C. The first step is a thermomechanical treatment or kneading process, and the above temperature range is required.

The second step may be performed at less than 110 °C, for example, 40 to 100 °C. The second step is a finishing step in which the crosslinking system is mixed, and relatively low temperature is required.

According to one embodiment of the present invention, the raw rubber may include styrene butadiene rubber and butadiene rubber.

According to one embodiment of the present invention, the raw rubber may include only styrene butadiene rubber and butadiene rubber.

Meanwhile, the raw rubber may further include at least one selected from butadiene rubber, isoprene-containing styrene butadiene rubber, nitrile-containing styrene butadiene rubber, neoprene rubber, chlorobutyl rubber, and bromobutyl rubber.

In addition, the raw rubber may further include natural rubber in addition to the above-described synthetic rubber. The natural rubber may be general natural rubber or modified natural rubber.

As the general natural rubber, any known natural rubber may be used, and the country of origin is not limited. The natural rubber mainly includes cis-1,4-polyisoprene, but may also include trans-1,4-polyisoprene according to required properties. Therefore, in addition to natural rubber containing cis-1,4-polyisoprene as a main component, natural rubber containing trans-1,4-isoprene as a main component, such as balata, a kind of rubber of the Sapotaceae family from South America, Rubber may also be included.

The modified natural rubber refers to a product obtained by modifying or refining the general natural rubber. For example, examples of the modified natural rubber include epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), and hydrogenated natural rubber.

According to one embodiment of the present invention, the filler may include carbon black and silica. For example, the filler may be made of carbon black and silica.

As the silica, any generally known silica may be used, and for example, commercially available Z-175, HD-165GR, US7000GR or 9000GR may be used.

According to one embodiment of the present invention, the silica content may be 20 to 30 times the carbon black content. That is, the main filler is silica and carbon black may be included in a small amount.

The silica content may be 60 to 150 parts by weight, for example, 90 to 140 parts by weight, based on 100 parts by weight of the raw rubber. When the silica content is within the above range, the physical properties of tire rubber are optimal.

The silica may have a nitrogen adsorption specific surface area per gram (N ₂ SA) of 100 to 180 m ² /g and a cetyl trimethyl ammonium bromide (CTAB) adsorption specific surface area of 110 to 170 m ² /g, The present invention is not limited thereto.

If the nitrogen adsorption specific surface area of the silica is less than 100 m ² /g, reinforcing performance by the silica filler may be disadvantageous, and if it exceeds 180 m ² /g, processability of the rubber composition may be disadvantageous. In addition, if the CTAB adsorption specific surface area of the silica is less than 110 m ² /g, the reinforcing performance of the silica filler may be disadvantageous, and if it exceeds 170 m ² /g, the processability of the rubber composition may be disadvantageous.

The carbon black may have a nitrogen adsorption specific surface area per gram (N ₂ SA) of 30 to 300 m ² /g and an oil absorption of n-dibutyl phthalate (DBP) of 60 to 180 cc/100 g, but the present invention This is not limited to this.

If the nitrogen adsorption specific surface area of the carbon black exceeds 300 m ² /g, processability of the rubber composition for a tire may be disadvantageous, and if it is less than 30 m ² /g, reinforcing performance by carbon black as a filler may be disadvantageous. In addition, if the DBP oil absorption amount of the carbon black exceeds 180 cc/100 g, the processability of the rubber composition may deteriorate, and if the DBP oil absorption amount is less than 60 cc/100 g, reinforcing performance by carbon black as a filler may deteriorate.

Representative examples of the carbon black are N110, N121, N134, N220, N231, N234, N242, N293, N299, S315, N326, N330, N332, N339, N343, N347, N351, N358, N375, N539, N550, N582 , N630, N642, N650, N683, N754, N762, N765, N774, N787, N907, N908, N990 or N991.

The carbon black may be included in, for example, 2 to 20 parts by weight, for example, 4 to 15 parts by weight, based on 100 parts by weight of the raw rubber.

According to one embodiment of the present invention, in the first step, a coupling agent may be further added and mixed. The coupling agent may be for enhancing the dispersion of silica.

The coupling agent may be, for example, a silane coupling agent. The silane coupling agent is a coupling agent containing Si, and the silane coupling agent reduces the polarity of silica by bonding to OH of silica so that it is well mixed with rubber. Any silane coupling agent commonly used in the field to which the present invention pertains may be used.

The silane coupling agent is a sulfide-based silane compound, a mercapto-based silane compound, a vinyl-based silane compound, an amino-based silane compound, a glycidoxy-based silane compound, a nitro-based silane compound, a chloro-based silane compound, a methacrylic silane compound, and mixtures thereof can be selected from.

The sulfide-based silane compound is bis (3-triethoxysilylpropyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (4-triethoxysilylbutyl) tetrasulfide, bis (3-tri Methoxysilylpropyl) tetrasulfide, bis(2-trimethoxysilylethyl)tetrasulfide, bis(4-trimethoxysilylbutyl)tetrasulfide, bis(3-triethoxysilylpropyl)trisulfide, bis(2 -triethoxysilylethyl)trisulfide, bis(4-triethoxysilylbutyl)trisulfide, bis(3-trimethoxysilylpropyl)trisulfide, bis(2-trimethoxysilylethyl)trisulfide, bis (4-trimethoxysilylbutyl)trisulfide, bis(3-triethoxysilylpropyl)disulfide, bis(2-triethoxysilylethyl)disulfide, bis(4-triethoxysilylbutyl)disulfide, bis( 3-trimethoxysilylpropyl) disulfide, bis(2-trimethoxysilylethyl)disulfide, bis(4-trimethoxysilylbutyl)disulfide, 3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyl Tetrasulfide, 3-triethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, 2-triethoxysilylethyl-N,N-dimethylthiocarbamoyltetrasulfide, 2-trimethoxysilylethyl-N ,N-dimethylthiocarbamoyltetrasulfide, 3-trimethoxysilylpropylbenzothiazolyltetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, 3 -trimethoxysilylpropyl methacrylate monosulfide and mixtures thereof.

The mercapto silane compound is selected from among 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane and mixtures thereof. can be chosen The vinyl-based silane compound may be selected from ethoxysilane, vinyltrimethoxysilane, and mixtures thereof. The amino-based silane compound is 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltriethoxysilane, 3-(2-aminoethyl)aminopropyltri methoxysilanes and mixtures. The glycidoxy-based silane compound is γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldimethoxysilane and mixtures thereof. The nitro-based silane compound may be selected from 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, and mixtures thereof. The chloro-based silane compound may be selected from 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 2-chloroethyltrimethoxysilane, 2-chloroethyltriethoxysilane, and mixtures thereof. . The methacrylic silane compound may be selected from γ-methacryloxypropyl trimethoxysilane, γ-methacryloxypropyl methyldimethoxysilane, γ-methacryloxypropyl dimethylmethoxysilane, and mixtures thereof.

According to one embodiment of the present invention, the content of the coupling agent may be 5 to 11 parts by weight based on 100 parts by weight of raw rubber. Considering the content of the raw rubber and the content of silica, when the content of the coupling agent is within the above range, the processing of the rubber composition is smooth and the physical properties of the crosslinked rubber are optimal.

The tire tread rubber composition may optionally further include various additives such as additional vulcanization agents, vulcanization accelerators, vulcanization accelerators, anti-aging agents, antioxidants, dispersants, or softeners. Any of the above various additives may be used as long as they are commonly used in the field to which the present invention belongs, and their contents are not particularly limited as they depend on the mixing ratio used in conventional tire tread rubber compositions.

As the vulcanizing agent, a sulfur-based vulcanizing agent can be preferably used. The sulfur-based vulcanizing agent is an inorganic vulcanizing agent such as powdered sulfur (S), insoluble sulfur (S), precipitated sulfur (S), colloidal sulfur, tetramethylthiuram disulfide (TMTD), tetraethyl Organic vulcanizers such as tetraethyltriuram disulfide (TETD) and dithiodimorpholine may be used. As the sulfur vulcanizing agent, elemental sulfur or a vulcanizing agent that produces sulfur, for example, amine disulfide, polymeric sulfur, etc. may be used.

The content of the curing agent refers to the above.

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

The vulcanization accelerators include sulfenamide-based, thiazole-based, thiuram-based, thiourea-based, guanidine-based, dithiocarbamic acid-based, aldehyde-amine-based, aldehyde-ammonia-based, imidazoline-based, xanthate-based and these Any one selected from the group consisting of combinations may be used.

Examples of the sulfenamide-based vulcanization accelerator include N-cyclohexyl-2-benzothiazylsulfenamide (CBS), N-tert-butyl-2-benzothiazylsulfenamide (TBBS), N,N-dicyclohexyl Any one selected from the group consisting of -2-benzothiazylsulfenamide, N-oxydiethylene-2-benzothiazylsulfenamide, N,N-diisopropyl-2-benzothiazolesulfenamide, and combinations thereof A sulfenamide-based compound of can be used.

Examples of the thiazole-based vulcanization accelerator include 2-mercaptobenzothiazole (MBT), dibenzothiazyl disulfide (MBTS), sodium salt of 2-mercaptobenzothiazole, and zinc salt of 2-mercaptobenzothiazole. , copper salt of 2-mercaptobenzothiazole, cyclohexylamine salt of 2-mercaptobenzothiazole, 2-(2,4-dinitrophenyl)mercaptobenzothiazole, 2-(2,6-di Any one thiazole-based compound selected from the group consisting of ethyl 4-morpholinothio)benzothiazole and combinations thereof may be used.

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

The thiourea-based vulcanization accelerator is, for example, any one thiourea-based selected from the group consisting of thiacarbamide, diethylthiourea, dibutylthiourea, trimethylthiourea, diortotolylthiourea, and combinations thereof compound can be used.

As the guanidine-based vulcanization accelerator, for example, any one guanidine-based compound selected from the group consisting of diphenylguanidine, diortolylguanidine, triphenylguanidine, orthotolylbiguanide, diphenylguanidine phthalate, and combinations thereof may be used. can

Examples of the dithiocarbamic acid-based vulcanization accelerator include zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, Zinc dibutyldithiocarbamate, zinc diamyldithiocarbamate, zinc dipropyldithiocarbamate, complex salts of zinc pentamethylenedithiocarbamate and piperidine, zinc hexadecylisopropyldithiocarbamate, octadecyl Zinc isopropyldithiocarbamate, Zinc dibenzyldithiocarbamate, Sodium diethyldithiocarbamate, Piperidine pentamethylenedithiocarbamate, Selenium dimethyldithiocarbamate, Tellurium diethyldithiocarbamate, Diethyldithiocarbamate Any one dithiocarbamate-based compound selected from the group consisting of cadmium dithiocarbamate and combinations thereof may be used.

The aldehyde-amine-based or aldehyde-ammonia-based vulcanization accelerator is, for example, an aldehyde selected from the group consisting of acetaldehyde-aniline reactants, butyraldehyde-aniline condensates, hexamethylenetetramine, acetaldehyde-ammonia reactants, and combinations thereof - 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 may be used, and as the xanthate-based vulcanization accelerator, for example, a xanthate-based compound such as zinc dibutylxanthogenate may be used. compound can be used.

The vulcanization accelerator may be included in an amount of 0.5 to 4.0 parts by weight based on 100 parts by weight of the raw rubber in order to maximize productivity enhancement and improvement of rubber properties through acceleration of vulcanization rate.

According to one embodiment of the present invention, the vulcanization accelerator in the second step may include a sulfenamide-based vulcanization accelerator, a guanidine-based vulcanization accelerator, a dithiocarbamic acid-based vulcanization accelerator, or any combination thereof. The present inventors have found through numerous iterative experiments that the use of the vulcanization accelerators of the above three systems as the vulcanization accelerator in the method for manufacturing a tire rubber composition according to an embodiment of the present invention is the optimal condition for the process or rubber properties.

The vulcanization accelerator is a compounding agent used in combination with the vulcanization accelerator to completely promote the effect, and any one selected from the group consisting of inorganic vulcanization accelerators, organic vulcanization accelerators, and combinations thereof may be used. .

As the inorganic vulcanization accelerator, any one selected from the group consisting of zinc oxide (ZnO), zinc carbonate, lead oxide, potassium hydroxide, and combinations thereof may be used. The organic vulcanization accelerator is selected from the group consisting of stearic acid, zinc stearate, palmitic acid, linoleic acid, oleic acid, lauric acid, dibutyl ammonium oleate, derivatives thereof, and combinations thereof Any one of them can be used.

In particular, as the vulcanization accelerator, the zinc oxide and the stearic acid may be used together. In this case, the zinc oxide is dissolved in the stearic acid to form an effective complex with the vulcanization accelerator, thereby removing advantageous sulfur during the vulcanization reaction. By making it, it facilitates the crosslinking reaction of rubber.

When the zinc oxide and the stearic acid are used together, they may be used in amounts of 1 to 10 parts by weight and 0.5 to 3 parts by weight, respectively, based on 100 parts by weight of the raw rubber, in order to serve as an appropriate vulcanization accelerator. When the contents of the zinc oxide and the stearic acid are less than the above range, the vulcanization rate is slow and productivity may decrease. When the content exceeds the above range, a scorch phenomenon may occur and physical properties may be deteriorated.

The softener is added to a rubber composition to facilitate processing by imparting plasticity to rubber or to reduce the hardness of vulcanized rubber, and refers to oils and other materials used in rubber compounding or rubber manufacturing. The softening agent refers to processing oil or oils included in other rubber compositions. As the softening agent, any one selected from the group consisting of petroleum oil, vegetable oil, and combinations thereof may be used, but the present invention is not limited thereto.

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

Representative examples of the paraffinic oil include P-1, P-2, P-3, P-4, P-5, and P-6 of Michang Oil Co., Ltd., and a representative example of the naphthenic oil is Michang Oil. and N-1, N-2, and N-3 of Michang Oil Co., Ltd., and A-2 and A-3 of Michang Oil Co., Ltd. as representative examples of the aromatic oil.

However, with the recent rise 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 the possibility of causing cancer is high, TDAE ( Treated distillate aromatic extract (MES) oil, MES (mild extraction solvate) oil, RAE (residual aromatic extract) oil, or heavy naphthenic oil may be preferably used.

In particular, the oil used as the softener has a total content of PAHs of 3% by weight or less, a kinematic viscosity of 95 or more (210 ° F SUS), an aromatic component in the softener of 15 to 25% by weight, and a naphthenic component with respect to the entire oil. A TDAE oil containing 27 to 37% by weight and 38 to 58% by weight of paraffinic components can be preferably used.

The TDAE oil improves the low-temperature characteristics and fuel efficiency of the tire including the TDAE oil, but also has advantageous properties against environmental factors such as the possibility of PAHs causing cancer.

The plant oils include castor oil, cottonseed oil, linseed oil, canola oil, soybean oil, palm oil, palm oil, peanut oil, pine oil, pine tar, tall oil, corn oil, rice bran oil, safflower oil, sesame oil, olive oil, sunflower oil, palm kernel oil, camellia oil , jojoba oil, macadamia nut oil, safflower oil, tung oil, and any one selected from the group consisting of combinations thereof may be used.

The softener is preferably used in an amount of 0 to 40 parts by weight based on 100 parts by weight of the raw rubber in view of improving processability of the raw rubber.

The antioxidant is an additive used to stop a chain reaction in which a tire is automatically oxidized 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 used.

Examples of the amine-based 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 may be used. The phenolic antioxidants include phenolic 2,2'-methylene-bis(4-methyl-6-tert-butylphenol), 2,2'-isobutylidene-bis(4,6-dimethylphenol), 2 Any one selected from the group consisting of ,6-di-t-butyl-p-cresol and combinations thereof may be used. As the quinoline-based antioxidant, 2,2,4-trimethyl-1,2-dihydroquinoline and derivatives thereof may be used, specifically 6-ethoxy-2,2,4-trimethyl-1,2-di consisting of hydroquinoline, 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 hydrocarbon may be preferably used.

The anti-aging agent should have high solubility in rubber in addition to anti-aging action, should have low volatility, be inactive with respect to rubber, and should not inhibit vulcanization, 1 to 10 parts by weight of the raw rubber It may be included in parts by weight.

The dispersant is an additive added to increase the dispersibility of the rubber composition. Examples of such dispersants include metal fatty acid salts. Examples of the metal fatty acid salt include Zinc Potassium Soap.

A typical amount of the antioxidant may be included, for example, from about 1 to about 5 parts by weight. Representative antioxidants include, but are not limited to, for example diphenyl-p-phenylenediamine and others.

Referring to FIG. 1 , a tire 10 includes a tread part 100 , a sidewall part 200 and a bead part 300 .

The tread portion 100 is a portion in contact with the ground in cross section, and serves to protect the tire from impact and trauma from the road surface. A plurality of blocks partitioned by grooves may be formed on the surface of the tread portion as described above to improve drainage of the tire.

A tire tread rubber composition prepared by the method for preparing a tire rubber composition according to an embodiment of the present invention is used for the tread.

The sidewall 200 and the bead portion 300 are sequentially positioned on both sides of the tread portion along the width direction of the tire.

The sidewall 200 is a part extending from both ends of the tread to form the side surface of the tire, and serves to withstand repeated contraction and expansion while driving and to protect the carcass layer 400 located on the inner surface. do

The bead part 300 is provided at both ends of the sidewall 200 to surround the end of the cord paper, and the bead part 300 includes a bead core 500 including a ring-shaped steel wire.

The carcass layer 400 is located between the left and right pair of bead parts 300, and is bonded to the tire rubber sheet inside the tire to form the skeleton of the tire. ) from the inside of the tire to the outside.

An inner liner 700 is located on one side of the inside of the carcass layer 400 and serves to prevent air inside the tire from escaping to the outside.

On the outer surface of the carcass layer 400 located on the tread part 100, a belt layer 600 is positioned as a reinforcing layer to increase the elasticity of the tread and to have maneuverability and stability.

The belt layer rubber may include a cobalt compound, and the cobalt compound includes cobalt salt, cobalt-boron ester, organic cobalt salt, inorganic cobalt salt, non-cobalt salt, etc. As the adhesive system, cobalt salt alone, cobalt- In addition to RH, cobalt-HRH, resin [e.g., methylene acceptor: phenolic, resorcinol-based, cresol-based, etc., or donor: hexamethylenetetraamine (HMT), hexamethoxymethylmelamine (HMMA), pentamethoxymethyl melamine (PMMA)] and the like.

In general, in order to improve adhesion, the adhesive system of adhesive compounded rubber is improved (cobalt-RH, cobalt-HRH, and their modified systems), resins used as adhesive aids are improved and performance is improved, cobalt salts used as adhesive aids are improved, and adhesion Improvement of rubber vulcanization system, use of new compound composition (reinforcement, carbon black, silica, polymer, chemicals), etc. are being used.

The content of the cobalt compound may include 0.2 to 5.0 parts by weight based on 100 parts by weight of raw rubber, but is not limited thereto.

A cap ply 800 including a hybrid cord may be disposed between the belt layer 600 and the tread portion 100 . The cap ply 800 can maintain the performance of the tire by suppressing the flow of the belt layer 600 during driving.

The tire tread rubber composition may be prepared through a conventional two-step continuous manufacturing process. That is, during the first step (non-productive step) of thermomechanical treatment or kneading at a maximum temperature ranging from 110 to 190 ° C., preferably from 135 to 160 ° C., and during the finishing step in which the crosslinking system is mixed, typically 110 It can be prepared in a suitable mixer using a second step (productive step) of mechanical treatment at a low temperature of less than ° C, for example, 40 to 100 ° C, but is not limited thereto.

A tire according to another embodiment of the present invention includes using the tire tread rubber composition when forming a green tire. As a method of forming a green tire using the tire tread rubber composition, any method conventionally used for manufacturing tires can be applied, and thus a detailed description thereof will be omitted herein.

1 illustrates a tire for a passenger car, but is not limited thereto, and may be a tire for a passenger car, a tire for racing, an airplane tire, a tire for agricultural machinery, an off-the-road tire, a truck tire, or a bus tire. there is. Also, the tire may be a radial tire or a bias tire, and is preferably a radial tire.

The present invention is explained in more detail through the following Examples and Comparative Examples. However, the examples are intended to illustrate the present invention, and the scope of the present invention is not limited only to these examples.

Comparative Examples and Examples

Each of the components in Table 1 below was added to a Banbury mixer in the ratios (unit: parts by weight) and mixed. After all ingredients were added to a Banbury mixer of intermeshing type, the ratio of each ingredient was adjusted so that the fill factor of 1.65L capacity was 0.65 to 0.70.

Comparative Example 1 Example 1 Example 2 Example 3 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Step 1 SBR 80 80 80 80 80 80 80 80 BR 20 20 20 20 20 20 20 20 Carbon black ¹⁾ 5 5 5 5 5 5 5 5 Silica ²⁾ 120 120 120 120 120 120 120 120 Coupling agent ³⁾ 6 6 6 6 6 6 6 6 oil ⁴⁾ 10 10 10 10 10 10 10 10 zinc oxide 2 2 2 2 2 2 2 2 stearic acid One One One One One One One One wax 2 2 2 2 2 2 2 2 Dispersant ⁵⁾ 3 3 3 3 3 3 3 3 Anti-aging agent ⁶⁾ One One One One One One One One brimstone - 0.01 0.1 0.2 0.3 0.5 0.7 0.9 Step 2 brimstone 1.8 1.79 1.7 1.6 1.5 1.3 1.1 0.9 CBS 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 DPG 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 ZDEC 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1

1) N134 (Columbian Chemicals)

2) EVONIK, HD-165GR

3) bis(3-triethoxysilylpropyl)tetrasulfide

4) RAE

5) EF-44 (STRUKTOL: Zinc Potassium Soap)

6) TMQ: 2,2,4-trimethyl-1,2-dihydroquinoline

evaluation example

Evaluation of unvulcanized rubber

[Evaluate seat condition]

2 shows pictures of the sheet state of the rubber composition in the first stage of Example 2 and Comparative Examples 1 to 5.

Referring to FIG. 2, it can be seen that the state of the sheet of Comparative Example 1 in which sulfur was not added at all in the first step was not good.

On the other hand, it can be seen that the sheet states of Example 2 in which 0.1 part by weight of sulfur was added in the first step and Comparative Examples 2 to 5 in which 0.3 to 0.9 parts by weight of sulfur were added were good.

[viscosity]

The viscosity of the rubber composition in the first step of Examples and Comparative Examples is shown in Table 2 below.

Comparative Example 1 Example 1 Example 2 Example 3 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Mooney Viscosity ¹⁾ 82 81 81 82 83 82 83 81 standard deviation ²⁾ 2.7 2.5 2.0 2.0 1.9 1.6 1.2 1.0

1) Pattern viscosity is the average value of values measured by randomly sampling 9 locations on the sheet. Pattern viscosity was measured by Daekyung Engineering's DMV-200C (100°C).

2) is the standard deviation of the above 9 values.

Referring to Table 2, it can be seen that the viscosities of the rubber compositions in the first step of Examples and Comparative Examples are similar, but in the case of Comparative Example 1 in which sulfur is not added in the first step, the variation in viscosity values is large. This can be said to indicate that the dispersibility of Comparative Example 1 is not good.

The processability of the rubber compositions subjected to the second step of Comparative Examples 1 to 5 and Example 2 was evaluated, and the results are shown in Table 3 below.

Scorch time and cure time evaluation

The scorch time at 135°C with Daekyung Engineering's DMV-200C and the curing time at 160°C with Daekyung Engineering's DRM-100 were evaluated. A short scorch time indicates poor processability, and too short a curing time may adversely affect the physical properties of vulcanized rubber.

In addition, a rubber sheet made of the rubber composition was vulcanized in a vulcanizer at 165° C. for 10 minutes to prepare a specimen. Physical properties such as specific gravity, hardness, tensile strength, dynamic properties, and dispersion were evaluated for each specimen. The results are shown in Table 3 below.

HD (hardness)

Using a Shore A-type durometer, one specimen was measured a total of 5 times on a smooth surface with a thickness of 6 mm or more and a diameter of 10 mm or more according to ASTM D2240-97, and the average value was determined.

Tensile properties

Tensile strength of the crosslinked specimen was measured using a tensile tester (INSTRON) according to ASTM D412. The specimen for measurement was manufactured in a sheet form using a hydraulic press and produced in a dumbbell form using a specimen cutter. As for the test conditions, the tensile speed was measured at 500 mm/min at room temperature. Tensile strength (T/S) is a value representing the stress value until the test piece breaks in the tensile tester, and the force received per unit area is measured.

elongation

Elongation was measured by a method of expressing the strain value in % until the test piece breaks in a tensile tester.

dynamic characteristics

Viscoelasticity as a dynamic characteristic was measured for Tanδ values from -70 ° C to 70 ° C under a 10 Hz frequency at 0.2% strain using a Gabo viscometer. The smaller the value of Tan δ at 60°C, the less heat generated during driving and the better the rolling resistance.

Dispersion measurement

The Payne Effect was measured at 60 °C with Alpha Technologies' RPA2000. A high relative number indicates poor dispersion (e.g. filler dispersion).

The evaluation results are shown in Table 3 below.

Comparative Example 1 Example 1 Example 2 Example 3 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Scorch Time t10 12.4 12.3 12.3 12.3 12.1 11.8 11.5 11.3 Cure Characteristic Rheometer(t40) 4.2 4.2 4.2 4.1 3.9 3.6 3.6 3.3 Specific Gravity 1.208 1.208 1.209 1.209 1.208 1.206 1.207 1.208 Hardness 65 65 65 65 64 66 65 66 300% modulus (kgf/cm ² ) 66 67 67 68 66 68 65 62 Tensile strength (kgf/cm ² ) 210 215 227 220 202 217 198 240 Elongation (%) 530 535 545 540 560 511 503 523 Tg(℃) -23 -23 -23 -23 -25 -25 -23 -24 tanδ @ 0℃ 0.297 0.298 0.296 0.296 0.296 0.301 0.299 0.295 tanδ @ 60℃ 0.140 0.138 0.135 0.136 0.137 0.137 0.133 0.136 Payne Effect 658 620 621 619 614 603 589 560

From the results of Tables 2 and 3, it can be seen that there was no significant change in the scorch time and cure time in Examples 1 to 3 and Comparative Example 1.

Looking at Examples and Comparative Examples, it can be seen that the payne effect improves as the amount of sulfur added in the first step increases. On the other hand, it can be seen that the physical properties of the vulcanized rubber have no correlation with the amount of sulfur added in the first step.

Looking at Examples 1 to 3 and Comparative Examples 2 to 5, it can be seen that the scorch time and cure time are shortened as the amount of sulfur added in the first step increases.

Therefore, it can be seen that the example according to one embodiment of the present invention is superior to the comparative example when considering workability such as sheet state during processing, scorch time, and cure time.

Although the above has been described with reference to embodiments, those skilled in the art to variously modify and modify the present invention within the scope not departing from the spirit and scope of the present invention described in the claims of the present invention. You will understand that it can be changed.

10: tire
100: tread part
200: side wall
300: bead part
400: carcass layer
500: bead core
600: belt layer
700: inner liner
800: cap ply

Claims (9)

A first step of mixing 100 parts by weight of raw rubber, 90 to 140 parts by weight of filler (based on 100 parts by weight of the raw rubber) and 0.01 to 0.2 parts by weight of a vulcanizing agent (based on 100 parts by weight of the raw rubber); and
A second step of mixing 1.8 to 9.99 parts by weight of a vulcanization agent (based on 100 parts by weight of the raw rubber) and 0.5 to 4.0 parts by weight of a vulcanization accelerator (based on 100 parts by weight of the raw rubber) with the product of the first step; A method for producing a tire rubber composition. According to claim 1,
A method for producing a tire rubber composition, wherein the raw material rubber comprises styrene butadiene rubber and butadiene rubber. According to claim 1,
A method for producing a tire rubber composition, wherein the filler comprises carbon black and silica. According to claim 3,
A method for producing a tire rubber composition, wherein the silica content is 20 to 30 times the carbon black content. According to claim 1,
The method of manufacturing a tire rubber composition, wherein the first step is a step of adding and mixing a coupling agent. According to claim 1,
Wherein the first step is a step of adding and mixing a vulcanization accelerator, a softener, an anti-aging agent, a dispersant, or any combination thereof. According to claim 1,
In the second step, the vulcanization accelerator includes a sulfenamide-based vulcanization accelerator, a guanidine-based vulcanization accelerator, a dithiocarbamic acid-based vulcanization accelerator, or any combination thereof. According to claim 1,
A tire tread rubber composition prepared by the method for preparing the tire rubber composition. A tire made of the tire tread rubber composition of claim 8.

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