KR101647329B1 - Rubber composition for tire innerliner and tire manufactured by using the same - Google Patents

Abstract

The present invention relates to a rubber composition for a tire innerliner and a tire produced using the same, wherein the rubber composition for a tire innerliner comprises 40 to 60 parts by weight of carbon black, 15 to 35 parts by weight of a plate- By weight, and 3 to 7 parts by weight of hindered phenol, it is possible to exhibit excellent air permeability without lowering the modulus.

Description

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

TECHNICAL FIELD The present invention relates to a rubber composition for a tire inner liner capable of exhibiting excellent air permeability without lowering the modulus, and a tire manufactured using the same.

The inner liner of the tire is located at the innermost part of the structure of the tire, so that it does not leak air from the tire and the rim when it is attached to the vehicle, and maintains the air pressure in the tire. Accordingly, the air permeability of the rubber composition for a tire inner liner is required. In addition, due to the nature of the inner liner portion, the vehicle is subjected to repeated loads and repeated fatigue, resulting in endurance and crack resistance. In recent years, there has been an increasing demand for improvement in regeneration of inner liners as the demand for improvement in regeneration of tires has increased. In order to regenerate, the modulus of durability is high, but when the modulus is high, crack resistance and regeneration are disadvantageously deteriorated.

In order to obtain such moderate level of modulus, a method of controlling the amount of oil or resin during the production of the rubber composition for inner liner has been used. However, when the additive is varied, the air permeability may be lowered. If air permeability is lowered, it is difficult to maintain the air pressure inside the tire, resulting in poor durability. If the tensile properties are too low, the fatigue resistance may be advantageous, but the gauge is reduced by repetitive fatigue, and the cord located inside the inner liner is exposed.

An object of the present invention is to provide a rubber composition for a tire innerliner which can exhibit excellent air permeability without lowering the modulus.

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

In order to achieve the above object, the rubber composition for a tire inner liner according to an embodiment of the present invention comprises 40 to 60 parts by weight of carbon black, 15 to 35 parts by weight of a sheet-like inorganic filler, And 3 to 7 parts by weight of hindered phenol.

In the rubber composition for a tire inner liner, the raw material rubber may be butyl rubber.

The carbon black may have a nitrogen surface area per gram (N ₂ SA) of 30 to 40 m ² / g and an oil absorption amount of n-dibutyl phthalate (DBP) of 85 to 95 cc / 100 g Lt; / RTI >

The plate-shaped inorganic filler may be delaminated kaolin.

In addition, the plate-shaped inorganic filler may have a particle diameter of 0.7 to 4 탆 and an oil adsorption amount of 38 to 46 cc / 100 g.

The hindered phenol may be n-octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) butyl-4-hydroxyphenyl) propionate, pentaerythritol tetrakis [3- (3 ', 5'-di-tert- Methylenebis (4-ethyl-6-tert-butylphenol)], Butylphenol, triethylene glycol bis (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, propionate, 2,2-thio-diethylene bis [3- (3,5-di-tert- butylphenyl) N, N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide) (N, N ' 3,5-di-tert-butyl-4-hydroxy-hydrocinamide, 1,3,5-triethyl- Di-tert-butyl-4-hydroxybenzyl) benzene, 1,6-diethyl- -Hexanediol bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] hydroxyphenyl) propionate], 2- (2-hydroxyethylthio) ethyl-3,5-di-t-butyl- t-butyl-4-hydroxybenzoate, 4,4'-methylenebis (6-tert-butyl-o-cresol) Methylenebis (2-tert-amyl-ocresol), ethylene glycol bis- [3- (3,5-di-t- Butyl-4-hydroxyphenyl) propionate], 2,2-methylenebis (4-methyl-6- 4-methylenebis (2-tert-butylphenol), 2,2-methylenebis (4-methyl- , 6-di-tert-buthylphenol)) and mixtures thereof It can be selected.

The rubber composition for a tire innerliner may further comprise 0.3 to 1.7 parts by weight of a sulfur vulcanizing agent and 0.8 to 1.5 parts by weight of a thiazole vulcanization accelerator based on 100 parts by weight of the raw rubber.

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

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

The present invention improves air permeability and adhesion without decreasing the modulus by mixing a plate-shaped inorganic filler and hindered phenol in the production of a rubber composition for a tire innerliner containing carbon black as a raw material rubber and a reinforcing filler .

That is, the rubber composition for a tire innerliner according to an embodiment of the present invention is characterized by comprising 40 to 60 parts by weight of a reinforcing filler, 15 to 35 parts by weight of a plate-like inorganic filler, and 30 to 60 parts by weight of a hindered phenol 3 to 7 parts by weight of phenol.

Specifically, in the rubber composition, 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 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. Examples of the modified natural rubber include epoxidized natural rubber (ENR), 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.

Among these, butyl rubber has low gas permeability, exhibits excellent crack resistance and adhesion, and is more preferable because it has excellent air permeability compared to other rubbers.

The butyl rubber is a copolymer of isobutylene and isoprene, which is also referred to as isobutylene-isoprene rubber. Specifically, the butyl rubber may be a butyl rubber (IIR), a halogenated butyl rubber such as a brominated butyl rubber (Br-IIR) or a chlorinated butyl rubber (Cl-IIR), and a butyl rubber may be more preferable.

On the other hand, the rubber composition for a tire inner liner includes carbon black as a reinforcing filler.

Specifically, the carbon black has a nitrogen adsorption specific surface area (N ₂ SA) of 30 to 40 m ² / g and a DBP (n-dibutyl phthalate) content in consideration of the effect of improving the reinforcing property and improving the workability and air permeability. Carbon black of GPF (General Purpose Furnace) grade having an oil absorption of 85 to 95 cc / 100 g may be more preferable.

The nitrogen adsorption specific surface area and the DBP oil absorption amount of the carbon black should be satisfied simultaneously. If the nitrogen adsorption specific surface area is less than 30 m ² / g, there is a possibility that the reinforcing performance by the carbon black as the filler becomes unfavorable. If it exceeds 300 m ² / g, the workability of the rubber composition for a tire may be deteriorated. If the DBP oil absorption of the carbon black exceeds 180 cc / 100 g, the workability of the rubber composition may be deteriorated. If the DBP oil absorption is less than 60 cc / 100 g, the reinforcing performance of the carbon black as a filler may be deteriorated.

The carbon black may be contained in an amount of 40 to 60 parts by weight, preferably 50 to 60 parts by weight, per 100 parts by weight of the raw rubber. If the content of the carbon black is less than 40 parts by weight, the reinforcing performance of the carbon black as a filler may be deteriorated. If the content exceeds 60 parts by weight, the workability of the rubber composition may be deteriorated.

The rubber composition for a tire innerliner includes a plate-like inorganic filler for improving air permeability.

In general, the air permeability of the inner liner rubber composition is related to the path through which air is permeated. In order to make the path difficult for air to permeate inside, a path having a high aspect ratio, i.e., a plate closer to the plate, is longer and air permeability is improved. However, since the air permeability and the modulus are in a trade off relationship, the modulus tends to be lowered as the air permeability increases. When the modulus is lowered, the cross-linking density is lowered, and the gauge is easily deformed by repetitive fatigue, so that the cord located inside the inner liner rubber can be exposed, and the crosslinking density is lowered, There is a concern that it will be lost.

The plate-shaped inorganic filler acts advantageously as a gas barrier due to its specific shape, thus making the path through which air passes is advantageous to ensure air permeability.

Specifically, the plate-like inorganic filler may be either delaminated kaolin, a plate-like clay, talc, mica, layered double hydroxide, hydrotalcite, kaolin clay ), Silica, calcium phosphate, boron nitride, or aluminosilicate. Of these, the delaminated kaolin may be more preferable considering the air permeability improving effect and hence the modulus reduction.

In addition, the plate-like inorganic filler may have a particle diameter of 0.7 to 4 탆 and an oil adsorption amount of 38 to 46 cc / 100 g. If the particle size of the plate-like inorganic filler is less than 0.7 mu m, the shape characteristic is small and the effect of improving the air permeability is insignificant If it exceeds 4 탆, the modulus may decrease. More preferably 1 to 3 占 퐉. If the oil adsorption amount is less than 38 cc / 100 g, the modulus may decrease. If the oil adsorption amount exceeds 46 cc / 100 g, the processability may be disadvantageous.

The plate-like inorganic filler preferably has an aspect ratio of 5 or more, more preferably 10 to 200, in terms of the ratio of the diameter to the thickness of the particles.

It is preferable that the plate-like inorganic filler is contained in an amount of 15 to 35 parts by weight based on 100 parts by weight of the raw rubber. When the content of the plate-shaped inorganic filler is less than 15 parts by weight, the effect of using the plate-shaped inorganic filler is insignificant. When the content is more than 35 parts by weight, the modulus of the rubber composition and the workability may decrease. Preferably 20 to 35 parts by weight.

The rubber composition for a tire innerliner includes hindered phenol.

In order to prevent modulus reduction caused by the use of the above-mentioned plate-shaped inorganic filler in the rubber composition for a tire inner liner, it is required to use a large amount of an inorganic filler in order to maintain a proper level. In addition, since the chain is short due to the plate shape, the tensile property may be deteriorated.

On the other hand, hindered phenol reacts with a radical generated by a chemical reaction or the like to delay the shortening of the chain, so that a sufficient level of modulus can be secured.

The hindered phenol is a compound having a phenolic structure in which an alkyl group is located on both sides or on one side of a hydroxy group, and may be specifically a compound represented by the following formula (1).

In the formula (1), R, R1 and R2 each independently represents a linear or branched alkyl group having 1 to 20 carbon atoms, or may be a bridging group in which a hydrocarbyl group or a second aromatic group is connected, Provided that at least one of R 1 and R 2 is a linear or branched alkyl group having 1 to 20 carbon atoms.

The alkyl group may be branched or branched alkyl group having 4 to 12 carbon atoms or t-butyl group.

The hydrocarbyl group may be substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms such as a linear or branched alkyl group or alkenyl group, an alicyclic hydrocarbon group such as a cycloalkyl group or a cycloalkenyl group, an aromatic, aliphatic or alicyclic hydrocarbon group And the hydrocarbyl group may be substituted with a halogen group, a hydroxy group, an alkoxy group, a mercapto group, an alkoxymethyl group, a nitro group, a nitroso group or a sulfoxy group, etc. .

In addition, the linking group is -CH ₂ - may be a such as ether _{linkage, -CH 2 CH 2 C (O} ) O- ester-based connection such as a - alkyl-series connecting group or -CH ₂ OCH _2, such as.

The hindered phenol having the above structure preferably has a weight average molecular weight of 300 to 10,000 g / mol, or 500 to 5000 g / mol. When the weight average molecular weight of the hindered phenol is less than 300 g / mol, the hindered phenol disappears in the mixing or vulcanization process, and the modulus improving effect may not be obtained. When the weight average molecular weight exceeds 10,000 g / mol, The compatibility and dispersibility of the rubber composition is deteriorated. As a result, there is a fear that the rubber property is lowered due to non-uniform dispersion in the rubber composition.

More specifically, the hindered phenol is n-octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) tert-butyl-4-hydroxyphenyl) propionate, pentaerythritol tetrakis [3- (3 ', 5'-di-tert- butyl-4'-hydroxyphenyl) propionate (4'-methylenebis (4 ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate], 2,2'- 3-tert-butyl-4-hydroxy-5-methylphenol), triethylene glycol bis (3-tert- methylphenyl) propionate, 2,2-thio-diethylene bis [3- (3,5-di-tert-butyl- N, N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide) (N, N'- N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinamide), 1,3,5- 3,5-diethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 1,6-hexanediolbis [3- (3,5-di-t-butyl-4-hydroxyphenyl) t-butyl-4-hydroxyphenyl) propionate], 2- (2-hydroxyethylthio) ethyl-3,5-di-t- Butyl-4-hydroxybenzoate, 4,4'-methylenebis (6-tert-butyl-o-cresol) ), 4,4'-methylenebis (2-tert-amyl-o-cresol), ethylene glycol bis- [3- (3, (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,2-methylenebis Methylene-6-tert-buthylphenol), 4,4-methylenebis (2,6-di-tert-butylphenol) (4 , 4-methylenebis (2,6-di-tert-buthylphenol)), and one of these They may be used singly or in a mixture of two or more.

The hindered phenol as described above acts as a reaction mechanism in the rubber composition for a tire inner liner as shown in Reaction Scheme 1 below. The following Reaction Scheme 1 is only one example for illustrating the present invention, but the present invention is not limited thereto.

[Reaction Scheme 1]

In the above reaction formula, P means polymer, and R is the same as defined above.

The hindered phenol may be contained in an amount of 3 to 7 parts by weight based on 100 parts by weight of the starting rubber. When the amount of the hindered phenol is less than 3 parts by weight, the improvement effect by the use of the hindered phenol is insignificant, and when it exceeds 7 parts by weight, the modulus of the hindered phenol may be increased due to excessive hindered phenol. Preferably 4 to 7 parts by weight.

The rubber composition for a tire innerliner according to the present invention may further contain various additives such as a vulcanizing agent, a vulcanization accelerator, a vulcanization accelerator, an adhesive and the like in addition to the above-mentioned components. Any of the various additives may 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 the compounding ratio used in a rubber composition for a conventional tire inner liner.

As the vulcanizing agent, a sulfur vulcanizing agent can be preferably 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.

It is preferable that the vulcanizing agent is included in an amount of 2 parts by weight or less, or 0.3 to 1.7 parts by weight based on 100 parts by weight of the raw rubber, from the viewpoint that the raw rubber is less sensitive to heat and chemically stable.

The vulcanization accelerator refers to an accelerator that accelerates the vulcanization rate or accelerates the retardation at 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.

As the guanidine-based vulcanization accelerator, any one of guanidine compounds selected from the group consisting of diphenyl guanidine, diorthotolyl guanidine, triphenyl guanidine, orthotolyl guanidine, diphenyl guanidine phthalate, and combinations thereof can be used have.

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-based or aldehyde-ammonia-based vulcanization accelerator include aldehyde selected from the group consisting of acetaldehyde-aniline reactant, butylaldehyde-aniline condensate, hexamethylenetetramine, acetaldehyde- -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.

Among these, the above-mentioned vulcanization accelerator may be more preferably a thiazole vulcanization accelerator as described above in order to maximize the productivity and rubber properties by accelerating the vulcanization rate.

The vulcanization accelerator may be added in an amount of 0.5 to 2 parts by weight, or 0.8 to 0.5 parts by weight based on 100 parts by weight of the raw rubber.

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 its promoting effect .

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 0.1 to 1.5 parts by weight based on 100 parts by weight of the raw material rubber, respectively, in order to serve as an appropriate vulcanization accelerating auxiliary. 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.

More preferably, the rubber composition for a tire inner liner may further comprise 0.3 to 1.7 parts by weight of a sulfur vulcanizing agent and 0.8 to 1.5 parts by weight of a thiazole vulcanization accelerator based on 100 parts by weight of the raw rubber.

The rubber composition for a tire innerliner 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 inner liner is not limited to the inner liner but may be included in various rubber components constituting the tire. Examples of the rubber component include a tread, a sidewall, a sidewall insert, an apex, a chafer or a wire coat.

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

The tire may be a passenger car tire, a racing tire, an airplane tire, an agricultural tire, an off-the-road tire, a truck tire or a bus tire, and may be a truck tire or a bus tire. Further, the tire may be a radial tire or a bias tire, and preferably a radial tire.

The rubber composition for a tire inner liner of the present invention shows excellent air permeability without degradation of modulus, and as a result, is more useful as an inner liner of a tire for trucks and buses.

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.

[Examples and Comparative Examples: Production of Rubber Composition]

The composition as shown in Table 1 below was added to a Banbury mixer to form a rubber composition, followed by vulcanization at 170 占 폚 for 15 minutes to prepare a specimen.

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Example 1 Example 2 Comparative Example 5 Comparative Example 6 Butyl rubber 100 100 100 100 100 100 100 100 Carbon black ^{1 )} 53 53 53 53 53 53 53 53 Silica - - - - - - - - Zinc oxide 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 Stearic acid 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Oil ^{2 )} 10 10 10 10 10 10 10 10 Plate type
Inorganic filler ^{3 )} - 10 20 20 20 20 20 40 Hindered phenol ⁴⁾ - - - One 4 7 10 7 Vulcanization ^{5 )} 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 Thiazole series
Accelerator 6) 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

(Unit: parts by weight)

1) Carbon black: GPF grade carbon black having a nitrogen adsorption specific surface area (N2SA) of 30 to 40 m ² / g and a DBP oil absorption of 85 to 95 cc /

2) Oil: Naphthenic oil

3) Plate-like inorganic filler: Dilaminate kaolin (particle diameter 0.7-4 탆, oil adsorption amount 38-46 cc / 100g, aspect ratio 10-200)

4) Hindered phenol: pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) butyl-4-hydroxyphenyl) propionate)) (weight average molecular weight: 1,178 g / mol)

5) vulcanizing agent: sulfur oil (sulfur treated by Zolfindustria)

6) Vulcanization accelerator: Dibenzothiazole disulfide (MBTS)

[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.

Tensile properties: Unvulcanized rubber was vulcanized at 170 ° C to prepare dumbbell-shaped specimens. The specimens were measured for hardness by ASTM shore-A method and the modulus was measured.

Air permeability: A circular specimen (50 mm in diameter, 250 μm in thickness) was vulcanized at 170 ° C. using unvulcanized rubber, and the gas permeability was measured at 30 ° C. at a measurement temperature of 30 ° C. Were measured.

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Example 1 Example 2 Comparative Example 5 Comparative Example 6 Tensile Properties Hardness
(Shorea) 52 50 47 51 53 54 56 57 300%
Modulus 33 29 21 27 34 36 40 41 Air permeability
(Indices) 100 108 114 110 106 102 98 105

As shown in Table 2, the rubber composition of Comparative Example 2, in which the delaminated kaolin was applied to the rubber composition of Comparative Example 1, improved air permeability due to the plate-like structure of kaolin. In addition, the rubber composition of Comparative Example 3 containing the delaminated kaolin at a higher content than Comparative Example 2 exhibited increased air permeability. However, the modulus of the rubber composition of Comparative Example 3 was lower than that of Comparative Example 2. The rubber composition of Comparative Example 4 containing 1 part by weight of hindered phenol containing the same amount of delaminated kaolin as Comparative Example 3 had a lower modulus level than that of Comparative Example 1, Compared to the control group. However, in the case of air permeability, the air permeability was lower than that of Comparative Example 3, but it was increased as compared with Comparative Example 1.

On the other hand, the rubber composition of Example 1, which contained 4 parts by weight of hindered phenol while containing the same amount of delaminated kaolin as that of Comparative Example 3, had a modulus level that was equal to that of Comparative Example 1, Showed an increased result.

Compared with Example 1 and Example 2, Comparative Example 5 showed that the air permeability was not lowered and the modlessness was increased even though the same amount of dilaminated kaolin was applied. Compared with Example 2, the air permeability of Comparative Example 6 was similar to that of Example 2, even though the lamellarized kaolin was applied twice or more, and it was confirmed that the modulus was increased.

Therefore, it can be seen that 15 to 100 parts by weight of the plate-shaped inorganic filler and 3 to 7 parts by weight of hindered phenol can be used in an optimal amount with respect to 100 parts by weight of the raw rubber.

From these results, it can be seen that the air permeability can be improved by using a plate-like inorganic filler, and at the same time, the degradation of the modulus due to the use of the plate-like inorganic filler can be prevented by using the hindered phenol in an optimum amount . That is, it can be seen that the air permeability can be improved without deteriorating the modulus by the optimum combination configuration according to the present invention including the plate-like inorganic filler and the hindered phenol at the optimum amount.

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)

With respect to 100 parts by weight of the raw rubber,
40 to 60 parts by weight of carbon black,
15 to 35 parts by weight of a sheet-like inorganic filler, and
And 3 to 7 parts by weight of hindered phenol,
The plate-like inorganic filler is delaminated kaolin,
The hindered phenol is n-octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate 4-hydroxyphenyl) propionate, triethylene glycol bis (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate ), 2,2-thio-diethylene bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] N, N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide) hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinamide), 1,3,5-triethyl-2,4,6- Benzyl) benzene (1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl- , 2-hydroxyethylthioethyl-3,5-di-t-butyl-4-hydroxybenzoate, 4,4'-methylenebis (6- tert-butyl o-cresol), 4,4'-methylenebis (2-tert-butyl-o-cresol), 4,4'-methylenebis 2-tert-amyl-o-cresol), ethyleneglycol bis- [3- (3,5-di-t- butyl-4-hydroxyphenyl) propionate] di-tert-buthylphenol), 4,4-methylenebis (2,6-di-tert-butylphenol) ), And a mixture thereof. ≪ RTI ID = 0.0 >
Rubber composition for tire inner liner. The method according to claim 1,
Wherein the raw rubber is a butyl rubber. The method according to claim 1,
Wherein the carbon black has a nitrogen surface area per gram of 30 to 40 m ² / g and an oil absorption of n-dibutyl phthalate of 85 to 95 cc / 100 g. delete The method according to claim 1,
Wherein the plate-shaped inorganic filler has a particle diameter of 0.7 to 4 占 퐉 and an oil adsorption amount of 38 to 46 cc / 100 g. delete The method according to claim 1,
Wherein 0.3 to 1.7 parts by weight of a sulfur vulcanizing agent and 0.8 to 1.5 parts by weight of a thiazole vulcanization accelerator are added to 100 parts by weight of the raw rubber. A tire produced by using the rubber composition for a tire innerliner according to claim 1.