KR101140184B1 - Rubber composition for tire bladder and bladder manufactured by using the same - Google Patents

Abstract

The present invention relates to a rubber composition for tire vulcanizing bladder and a bladder prepared using the same, comprising 100 parts by weight of raw material rubber, 10 to 100 parts by weight of reinforcing filler, and 5 to 30 parts by weight of titanium dioxide / silica nanocomposite. .

The rubber composition for tire vulcanizing bladder has a long life, excellent thermal conductivity, and prevents the inside of the bladder misting, thereby reducing the manufacturing cost and simplify the installation.

Vulcanization, bladder, titanium dioxide, TiO2, silica, nano, composite

Description

RUBBER COMPOSITION FOR TIRE BLADDER AND BLADDER MANUFACTURED BY USING THE SAME

The present invention relates to a rubber composition for a tire vulcanizing bladder and a bladder manufactured by using the same, and more particularly, serves as a fruit medium between the tire and steam as an internal heat source during tire vulcanization, and applies a constant pressure to the inside of the tire. The present invention relates to a rubber composition for a tire vulcanizing bladder that maintains a tire in a constant form and a bladder manufactured by using the same.

In general, a tire manufacturing process is performed through a molding process, which is a side work of each semi-finished product, to manufacture a green tire, and the manufactured green tire is subjected to a vulcanization process under high temperature and high pressure conditions. At this time, the green tire is subjected to a vulcanization process for a predetermined time through the internal and external heat sources of the steam and the mold.

Steam, which is an internal heat source, is indirectly transmitted to the green tire through a fruit entity called a bladder, and the bladder also serves to maintain a constant shape inside the tire by applying a constant pressure to the inside of the tire. The bladder is used in the vulcanization process of many green tires, repeats expansion and contraction, and also serves to force uncrosslinked rubber.

Rubber, which is a polymer used in the rubber composition for vulcanizing bladder, has a low thermal conductivity, which makes it difficult to transfer internal heat sources to green tires, and when the internal heat sources are not all delivered, the bleeding phenomenon occurs inside the bladder. It also lowers. In addition, the bladder is subject to constant fatigue due to repeated use and expansion and contraction and severe use conditions of high elongation.

Accordingly, in the rubber composition for the bladder, it is the most important technical problem to maintain the required properties even in the repeated fatigue and excellent thermal conductivity and prevent the internal fogging phenomenon to make the process smoothly.

Meanwhile, carbon black is conventionally used as a reinforcing agent of a rubber composition for tire vulcanization bladder, but when the carbon black is used, fog occurs in the bladder during the vulcanization process, which lowers the temperature of steam, thereby lowering the productivity of the process. Let's do it. In addition, the carbon black may not have good dispersibility, which may reduce fatigue resistance, and these problems may cause deterioration of a bladder to maintain a constant shape.

It is an object of the present invention to provide a rubber composition for tire vulcanizing bladder that has a long life, excellent thermal conductivity, prevents the inside of the bladder misting, thereby bringing down the manufacturing cost and the simplification of the equipment.

Another object of the present invention is to provide a bladder prepared using the rubber composition for tire vulcanization bladder.

In order to achieve the above object, the rubber composition for tire vulcanizing bladder according to an embodiment of the present invention comprises 100 parts by weight of raw rubber, 10 to 100 parts by weight of reinforcing filler, and 5 to 30 parts by weight of titanium dioxide / silica nanocomposite. do.

The titanium dioxide / silica nanocomposite has a particle diameter of 10 to 50 nm titanium dioxide and a particle diameter of 60 to 150 nm, a nitrogen adsorption specific surface area of 110 to 130 m 2 / g, and a CTAB (cetyl trimethyl ammonium bromide) adsorption specific surface area of 110 to 50 nm. And 130 m 2 / g of silica.

The titanium dioxide / silica nanocomposite may include 20:80 to 10:90 weight ratio of the titanium dioxide and the silica.

The raw rubber may include 70 to 90 parts by weight of natural rubber and 10 to 30 parts by weight of butadiene rubber.

The reinforcing filler may be any one selected from the group consisting of carbon black, silica, and combinations thereof.

The rubber composition for tire vulcanizing bladder may further include 1 to 20 parts by weight of a coupling agent.

Bladder according to another embodiment of the present invention is manufactured using the rubber composition for tire vulcanization bladder.

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

The rubber composition for tire vulcanizing bladder includes 100 parts by weight of raw rubber, 10 to 100 parts by weight of reinforcing filler, and 5 to 30 parts by weight of titanium dioxide / silica nanocomposite.

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

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

The general natural rubber may be used as long as it is known as natural rubber, and the origin and the like are not limited. The natural rubber contains cis-1,4-polyisoprene as a main agent, but may also include trans-1,4-polyisoprene depending on the required properties. Therefore, the natural rubber includes, in addition to the natural rubber containing cis-1,4-polyisoprene as a main agent, for example, a natural containing trans-1,4-isoprene as a main agent such as a balata, which is a kind of rubber of South American sapotagua. Rubber may also be included.

The modified natural rubber means a modified or refined general natural rubber. For example, the modified natural rubber may include epoxidized natural rubber (ENR), deproteinized natural rubber (DPNR), hydrogenated natural rubber, and the like.

Synthetic rubber is styrene butadiene rubber (SBR), modified styrene butadiene rubber, butadiene rubber (BR), modified butadiene rubber, chloro sulfonated polyethylene rubber, epichlorohydrin rubber, fluorine rubber, silicone rubber, nitrile rubber, hydrogenated 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, Hypalon Rubber, Chloroprene Rubber, Ethylene vinyl acetate rubber, acrylic rubber, hydrin rubber, vinyl benzyl chloride styrene butadiene rubber, bromo methyl styrene butyl rubber, maleic acid styrene butadiene rubber, carboxylic acid styrene butadiene rubber, epoxy isoprene rubber, maleic acid ethylene propylene rubber, carboxylic acid Nitrile Butadiene High 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.

The synthetic rubber may be preferably any one selected from the group consisting of styrene butadiene rubber, polyisoprene rubber, butadiene rubber, butyl rubber, halogenated rubber, ethylene-propylene rubber, and combinations thereof, but is not limited thereto.

In particular, the raw material rubber may include 70 to 90 parts by weight of natural rubber and 10 to 30 parts by weight of butadiene rubber. The raw rubber including 70 to 90 parts by weight of the natural rubber and 10 to 30 parts by weight of butadiene rubber is used in the vulcanization process of a number of green tires when used for tire vulcanization bladder and has a long life even when repeated expansion and contraction.

The reinforcing filler may be any one selected from the group consisting of carbon black, silica, and combinations thereof.

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

When the nitrogen adsorption specific surface area of the carbon black exceeds 300m ² / g may be disadvantageous in workability of the rubber composition for tires, less than 30m ² / g may be disadvantageous reinforcement performance by the carbon black filler. In addition, when the DBP oil absorption of the carbon black exceeds 180cc / 100g, the workability of the rubber composition may be lowered. If the DBP oil absorption amount of the carbon black is less than 60cc / 100g, the reinforcing performance by the carbon black as a filler may be disadvantageous.

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 an amount of 10 to 100 parts by weight based on 100 parts by weight of the raw material rubber. If the carbon black content is less than 10 parts by weight, the reinforcing performance of the carbon black, which is a filler, may be lowered, and more than 100 parts by weight. The workability of the rubber composition may be deteriorated.

The silica has a nitrogen adsorption specific surface area (N ₂ SA) of 100 to 180 m ₂ / g, CTAB (cetyl trimethyl ammonium bromide) adsorption specific surface area may be 110 to 170 m 2 / g, but the present invention This is not limited to this.

The silica can be used both wet or dry method, and commercially available products such as ultra-sil VN2 (manufactured by Degussa Ag), ultra-sil VN3 (manufactured by Degussa Ag), Z1165MP (manufactured by Rhodia) or Z165GR (manufactured by Rhodia) Can be.

The silica may be included in an amount of 10 to 100 parts by weight based on 100 parts by weight of the raw material rubber, preferably 30 to 70 parts by weight, and more preferably 30 to 50 parts by weight. When the content of the silica is less than 10 parts by weight, the reinforcing performance by the filler silica may be lowered, and when it exceeds 100 parts by weight, the processability of the rubber composition may be deteriorated.

When using silica as the reinforcing filler, the rubber composition for tire vulcanization bladder may further include a coupling agent to improve the dispersibility of the silica.

Examples of the coupling agent include a sulfide silane compound, a mercapto silane compound, a vinyl silane compound, an amino silane compound, a glycidoxy silane compound, a nitro silane compound, a chloro silane compound, a methacryl silane compound, and a combination thereof. It can be used any one selected from the group consisting of, sulfide-based silane compound can be preferably used.

The sulfide-based silane compound may be 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-trimethoxy Sisylethyl) disulfide, bis (4-trimethoxysilylbutyl) disulfide, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N, N-dimethyl Thiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-trimethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilyl Propylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazole tetrasulfide, 3-trimethoxysilylpropylmethacrylate monosulfide, 3-trimethoxysilylpropylmethacrylate monosulfide and combinations thereof It may be any one selected from the group consisting of.

The mercapto silane compound includes 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyl triethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, and combinations thereof. It may be any one selected from the group consisting of. The vinyl silane compound may be any one selected from the group consisting of ethoxysilane, vinyltrimethoxysilane, and combinations thereof. The amino silane compound is 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropyltriethoxysilane, 3- (2-aminoethyl) aminopropyltri It may be any one selected from the group consisting of methoxysilane and combinations thereof.

The glycidoxy silane compounds include γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and γ-glycidoxypropylmethyldimethoxysilane And combinations thereof may be any one selected from the group consisting of. The nitro 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. It can be any one.

The methacrylic silane compound is any one selected from the group consisting of γ-methacryloxypropyl trimethoxysilane, γ-methacryloxypropyl methyldimethoxysilane, γ-methacryloxypropyl dimethyl methoxysilane, and combinations thereof Can be.

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 material rubber to improve 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 processability of rubber may be reduced. When the content of the coupling agent exceeds 20 parts by weight, the interaction between silica and rubber is so strong that the physical properties of the rubber composition for vulcanizing bladder This can be degraded.

The titanium dioxide / silica nanocomposite is a nano-sized titanium dioxide complexed with silica, and when the rubber composition for tire vulcanization bladder includes it, fatigue resistance, thermal conductivity and hydrophilicity are improved.

That is, the titanium dioxide / silica nanocomposite can prevent fatigue performance deterioration due to the dispersibility of the reinforcing filler and prevent the deterioration of tire shape retention during vulcanization, and the frost inside the bladder by the internal heat source (steam). Can solve the problem.

The titanium dioxide / silica nanocomposite is a silica having a particle diameter of 10 to 50 nm and a particle diameter of 60 to 150 nm, a nitrogen adsorption specific surface area of 110 to 130 m 2 / g, and a CTAB adsorption specific surface area of 110 to 130 m 2 / g. Can be prepared by mixing by the sol-gel method.

When the particle diameter of the titanium dioxide is within the above range, it is possible to prepare the titanium dioxide / silica nanocomposite through the sol-gel method, wherein the particle diameter is 60 to 150 nm, and the nitrogen adsorption specific surface area is 110 to 130 m 2 / g. In the case of using a silica having a CTAB adsorption specific surface area of 110 to 130 m 2 / g, the rubber composition containing the titanium dioxide / silica nanocomposite is preferable in that the processability and dispersibility of the rubber composition are improved.

The titanium dioxide / silica nanocomposite may be included in an amount of 5 to 30 parts by weight, preferably 15 to 25 parts by weight, based on 100 parts by weight of the raw material rubber. When the content of the titanium dioxide / silica nanocomposite is less than 5 parts by weight based on 100 parts by weight of the raw material rubber, reinforcement is not obtained to obtain the required physical properties, and when it exceeds 30 parts by weight, processing is difficult and mechanical force increases and shrinks. It is not desirable for the bladder to repeat expansion and expansion.

In addition, the titanium dioxide / silica nanocomposite may include the titanium dioxide and the silica in a weight ratio of 20:80 to 10:90. When the weight ratio of the titanium dioxide and the silica is in the above range, it is added to the rubber composition for tire vulcanization bladder to improve the fatigue resistance, thermal conductivity and hydrophilicity. When the weight ratio of the titanium dioxide and the silica is out of the range, fatigue resistance may be degraded due to the dispersibility of the reinforcing filler, or a problem of deterioration of tire shape retention may occur when vulcanizing, and the bladder may be caused by an internal heat source (steam). Steaming inside can cause problems.

The rubber composition for tire vulcanizing bladder may further include various additives such as additional vulcanizing agents, vulcanization accelerators, vulcanization accelerators, anti-aging agents or softeners. The various additives may be used as long as they are commonly used in the field of the present invention, the content thereof is not particularly limited, depending on the compounding ratio used in the conventional rubber composition for tire vulcanization bladder.

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

The sulfur-based vulcanizing agents include inorganic vulcanizing agents such as powdered sulfur (S), insoluble sulfur (S), precipitated sulfur (S) and colloidal sulfur, tetramethylthiuram disulfide (TMTD), tetra Organic vulcanizing agents, such as ethylethyluram disulfide (TEET) and dithiodimorpholine, can be used. Specifically, as the sulfur vulcanizing agent, a vulcanizing agent which produces elemental sulfur or sulfur, for example, amine disulfide, polymer sulfur, or the like can be used.

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

The vulcanizing agent is preferably included in an amount of 0.5 to 4 parts by weight based on 100 parts by weight of the raw material rubber, which is preferable in that the raw material rubber is less sensitive to heat and chemically stable.

The vulcanization accelerator refers to an accelerator that promotes the rate of vulcanization or promotes delay in the initial vulcanization stage.

The vulcanization accelerators include sulfenamides, thiazoles, thiurams, thioureas, guanidines, dithiocarbamic acids, aldehydes-amines, aldehydes-ammonias, imidazolines, xanthates and the like. Any one selected from the group consisting of a combination can be used.

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

Examples of the thiazole vulcanization accelerators 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 thiazole compound selected from the group consisting of ethyl 4-morpholinothio) benzothiazole and combinations thereof can be used.

Examples of the thiuram-based vulcanization accelerators include tetramethyl thiuram disulfide (TMTD), tetraethyl thiuram disulfide, tetramethyl thiuram monosulfide, dipentamethylene thiuram disulfide, dipentamethylene thiuram monosulfide and dipentamethylene. Any thiuram-based compound selected from the group consisting of thiuram tetrasulfide, dipentamethylene thiuram hexasulfide, tetrabutyl thiuram disulfide, pentamethylene thiuram tetrasulfide, and combinations thereof can be used.

Examples of the thiourea vulcanization accelerators include thiourea selected from the group consisting of thiacarbamide, diethylthioiso, dibutylthiourea, trimethylthiourea, diorthotolylthiourea, and combinations thereof. System compounds can 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. Can be.

Examples of the dithiocarbamic acid-based vulcanization accelerators include ethylphenyldithiocarbamate zinc, butylphenyldithiocarbamate zinc, sodium dimethyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, Zinc dibutyldithiocarbamate, zinc diamyldithiocarbamate, zinc dipropyldithiocarbamate, zinc salt of pentamethylenedithiocarbamate and piperidine, hexadecylisopropyldithiocarbamate zinc, octadecyl Isopropyldithiocarbamate zinc dibenzyldithiocarbamate zinc, sodium diethyldithiocarbamate, pentamethylenedithiocarbamate piperidine, dimethyldithiocarbamate selenium, diethyldithiocarbamate tellurium, dia One dithiocarbamic acid compound selected from the group consisting of cadmium didicarbamate and combinations thereof can be used.

The aldehyde-amine-based or aldehyde-ammonia based vulcanization accelerator, for example, acetaldehyde-aniline reactant, butylaldehyde-aniline condensate, hexamethylenetetramine, acetaldehyde-ammonia reactant and combinations thereof -Amine based or aldehyde-ammonia based compounds can be used.

As said imidazoline type vulcanization accelerator, imidazoline type compounds, such as 2-mercaptoimidazoline, can be used, for example, As said xanthate type vulcanization accelerator, xanthate type, such as zinc dibutyl xanthogenate Compounds 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 material rubber in order to maximize productivity and rubber properties by promoting the vulcanization rate.

The vulcanization accelerator is a compounding agent used in combination with the vulcanization accelerator to complete its promoting effect. Any one selected from the group consisting of inorganic vulcanization accelerators, organic vulcanization accelerators and combinations thereof can be used. .

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. 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. You can use either one.

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

When using the zinc oxide and the stearic acid together may be used in 1 to 5 parts by weight and 0.5 to 3 parts by weight with respect to 100 parts by weight of the raw material rubber, respectively, to serve as a suitable vulcanization accelerator.

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 softener may be any one selected from the group consisting of petroleum oil, vegetable oil and combinations thereof, but the present invention is not limited thereto.

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

Representative examples of the paraffinic oil include P-1, P-2, P-3, P-4, P-5, and P-6 of Michang Oil, Inc. A representative example of the naphthenic oil is Michang oil. N-1, N-2, N-3, etc. of the corporation | Co., Ltd. are mentioned, As a representative example of the said aromatic oil, A-2, A-3, etc. of Michang Oil Corporation are mentioned.

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

In particular, the oil used as the softener has a total content of PAHs component of 3% by weight or less, a kinematic viscosity of 95 ° C or higher (210 ° F SUS), 15-25% by weight of aromatic components in the softener, nap TDAE oils having 27 to 37% by weight of the ten component and 38 to 58% by weight of the paraffinic component can be preferably used.

The TDAE oil has an excellent characteristic against environmental factors such as the possibility of causing cancer of PAHs while improving fatigue resistance and lifespan characteristics of the tire vulcanization bladder including the TDAE oil.

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 It may be used any one selected from the group consisting of jojoba oil, macadamia nut oil, saflower flower oil, tung oil and combinations thereof.

The softening agent is preferably used in an amount of 0 to 150 parts by weight based on 100 parts by weight of the raw material rubber, in terms of improving the processability of the raw material rubber.

The anti-aging agent is an additive used to stop the chain reaction in which the bladder 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.

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 can be used.

The phenolic anti-aging agent is 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 can be used.

As the quinoline anti-aging agent, 2,2,4-trimethyl-1,2-dihydroquinoline and derivatives thereof may be used, and specifically 6-ethoxy-2,2,4-trimethyl-1,2-di 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.

Wax hydrocarbon may be preferably used as the wax.

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.

The rubber composition for tire vulcanization bladder may be prepared through a conventional two-step continuous manufacturing process. That is, during the finishing step in which the first step of thermomechanical treatment or kneading at a maximum temperature ranging from 110 to 190 ° C., preferably from 130 to 180 ° C. (called “non-production” step) and the crosslinking system are mixed, Typically produced in a suitable mixer using a second step (called a "production" step) of mechanical treatment at low temperatures of less than 110 ° C, for example 40-100 ° C, but the invention is limited thereto. no.

The rubber composition for the tire vulcanizing bladder may be used for the vulcanizing bladder as well as included in various rubber components constituting the tire. Such rubber components include treads (tread caps and tread bases), sidewalls, sidewall inserts, apex, chafers, wire coats or innerliners, and the like.

Bladder according to another embodiment of the present invention is manufactured using the rubber composition for tire vulcanization bladder. The method for manufacturing a bladder using the rubber composition for tire vulcanizing bladder is applicable to any method used in the manufacture of a bladder in the prior art, and thus detailed description thereof will be omitted.

The rubber composition for tire vulcanizing bladder of the present invention has a long life, excellent thermal conductivity, prevents the inside of the bladder misting, thereby reducing the manufacturing cost and simplify the installation.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice 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]

( Example  One)

A rubber composition for tire vulcanization bladder was prepared by adding 50 parts by weight of silica and 5 parts by weight of a titanium dioxide / silica nanocomposite as a reinforcing filler to a raw material rubber mixed with natural rubber and butadiene rubber using the composition shown in Table 1 below. The rubber composition was prepared according to a conventional method for preparing a rubber composition.

( Example  2)

A rubber composition for tire vulcanization bladder was prepared in the same manner as in Example 1 except that 40 parts by weight of silica and 15 parts by weight of titanium dioxide / silica nanocomposite were added to the raw material rubber mixed with natural rubber and butadiene rubber. Prepared.

( Example  3)

A rubber composition for tire vulcanizing bladder was prepared in the same manner as in Example 1, except that 30 parts by weight of silica and 25 parts by weight of titanium dioxide / silica nanocomposite were added to the raw material rubber mixed with natural rubber and butadiene rubber. Prepared.

( Comparative example  One)

A rubber composition for tire vulcanizing bladder was prepared in the same manner as in Example 1 except that 30 parts by weight of carbon black was added as a reinforcing filler to the raw material rubber mixed with natural rubber and butadiene rubber.

[Table 1] (Unit: parts by weight)

Item Example 1 Example 2 Example 3 Comparative Example 1 Natural rubber 80 80 80 80 Butadiene rubber 20 20 20 20 Silica 50 40 30 - Silane coupling agent 9 8 5 - Carbon black - - - 30 Titanium dioxide / silica
Nanocomposites ^{1 )} 5 15 25 - Zinc oxide 2 2 2 2 Stearic acid One One One One brimstone 2 2 2 2 Vulcanization accelerator 1.8 1.8 1.8 1.8

1) Titanium dioxide / silica nanocomposite: 20 parts by weight of titanium dioxide (manufactured by Degussa) having a particle diameter of 10 to 50 nm, a particle diameter of 60 to 150 nm, a nitrogen adsorption specific surface area of 110 to 130 m 2 / g, and a CTAB adsorption specific surface area Prepared by mixing 80 parts by weight of the 110 to 130 m 2 / g silica (manufactured by Degussa) by the sol-gel method.

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

Evaluation results of the rubber specimens prepared in Examples 1 to 3 and Comparative Example 1 are shown in Table 2, the measurement was in accordance with the following method.

(1) Tensile Properties: It was measured according to ASTM D412 test method using an Instron tester.

(2) Fatigue resistance properties: measured according to the ASTM D430-73 test method, the fatigue cycle until the specimen breaks through repeated fatigue was measured.

(3) Thermal Conductivity: The thermal conductivity was measured according to ASTM E 1461 test method using LFA 457.

TABLE 2

division Example 1 Example 2 Example 3 Comparative Example 1 Tensile Properties Hardness 73 71 69 72 300% modulus (kgf / cm ² ) 117 126 135 105 Tensile strength (kgf / cm ² ) 225 241 252 211 % Elongation 436 429 418 450 Fatigue resistance Cycle 22,481 23,670 24,079 18,758 Thermal conductivity W / mK 0.251 0.298 0.326 0.247

In addition, the life of the bladder was measured, and the results are shown in Table 3 below. The life comparison of the bladder is based on the life of Comparative Example 1 based on 100, and the number of times of use is compared.

[Table 3]

Example 1 Example 2 Example 3 Comparative Example 1 Life comparison 105 118 130 100

Referring to Tables 2 and 3 above, in the case of tensile properties, Examples 1 to 3 to which titanium dioxide / silica nanocomposites were added are generally improved compared to Comparative Example 1 using carbon black, which is a conventional reinforcing filler. . This is in the case of Examples 1 to 3 it can be seen that the reinforcement of the titanium dioxide / silica nanocomposite is superior to the carbon black showing a higher tensile strength than Comparative Example 1. On the other hand, referring to Examples 1 to 3, it can be seen that the tensile strength also tends to increase as the content of the titanium dioxide / silica nanocomposites increases.

In addition, the fatigue resistance and the life of the bladder are also advantageously shown in Examples 1 to 3 as compared to Comparative Example 1. In addition, it can be seen that in Examples 1 to 3, the thermal conductivity is better than that of Comparative Example 1 by using the titanium dioxide / silica nanocomposite.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims (7)

100 parts by weight of raw rubber, 10 to 100 parts by weight of reinforcing fillers, and 5 to 30 parts by weight of titanium dioxide / silica nanocomposite, The titanium dioxide / silica nanocomposite is a rubber composition for tire vulcanizing bladder comprising the titanium dioxide and the silica in a 20:80 to 10:90 weight ratio. The method of claim 1, The titanium dioxide / silica nanocomposite Titanium dioxide having a particle diameter of 10 to 50 nm and Silica having a particle diameter of 60 to 150 nm, a nitrogen adsorption specific surface area of 110 to 130 m 2 / g, and a CTAB (cetyl trimethyl ammonium bromide) adsorption specific surface area of 110 to 130 m 2 / g A rubber composition for a tire vulcanizing bladder comprising a. delete The method of claim 1, The raw material rubber 70 to 90 parts by weight of natural rubber and 10 to 30 parts by weight of butadiene rubber A rubber composition for a tire vulcanizing bladder comprising a. The method of claim 1, The reinforcing filler is any one selected from the group consisting of carbon black, silica and combinations thereof, rubber composition for tire vulcanizing bladder. The method of claim 1 The rubber composition for tire vulcanizing bladder is a rubber composition for tire vulcanizing bladder further comprising 1 to 20 parts by weight of a coupling agent. A bladder manufactured using the rubber composition for tire vulcanizing bladder according to any one of claims 1, 2, and 4 to 6.