KR20090111200A - Tire tread rubber composition - Google Patents

Abstract

PURPOSE: A tire tread rubber composition is provided to improve dispersibility of carbon black on which surface is treated and enhance process. CONSTITUTION: A tire tread rubber composition contains 10-80 weight parts of surface-treated carbon black and 5-30 weight parts of reinforcing filler based on the 100 weight parts of raw rubber. The reinforcing filler is selected from silica, titanium dioxide, clay, layered silicate, tungsten, talc, and syndiotactic-1,2-polybutadiene (SPB).

Description

Tire tread rubber composition

The present invention relates to a tire tread rubber composition, and more particularly, in the conventional tire tread rubber composition, by using carbon black surface-treated as one of the reinforcing fillers, the characteristics of agglomeration between fillers are reduced to improve the dispersibility of the filler. The present invention relates to a tire tread rubber composition capable of improving physical properties by increasing the amount of bonding between the raw material rubber and the filler.

The tire tread rubber composition of the present invention may be coated with silica, titanium oxide, clay, layered silicate, tungsten, talc, in addition to the surface treated carbon black. The physical properties of the rubber composition can be improved by using any one or more reinforcing fillers selected from the group of syndiotactic-1,2-polybutadiene (SPB).

The performance required for a passenger tire varies greatly depending on the part of the tire, its role and where it is used.

The rubber used for the side wall where the information of the tire is written has to be exposed to ultraviolet rays from the sun, to perform frequent flexion movements, and to emit heat generated from the tires to the outside. The heat should be excellent.

On the other hand, the rubber used for the tire tread in direct contact with the ground should not only have excellent adjustment stability, ride comfort, fuel economy, and snow performance on the driving surface, but also excellent wear resistance, braking force, and durability in terms of economic problems. Should be.

The tire tread must satisfy various characteristics as mentioned above because the tire is important to move, support, and maintain the vehicle, in particular, the vehicle moves. However, these performances are in a trade-off relationship that partially betrays each other, that is, the other side gets worse, so it is difficult to simultaneously improve the various properties required for the tread rubber. .

Cars are now owned by many people for work, living, leisure, and other reasons. Among those who own a car, economically affordable people may own more than one vehicle, but they are essential for work and living. There are people who need vehicles. Since automobiles use four tires, most tires are economically damaged because four tires must be replaced at the same time. These economic problems are burdened by both economically and inadequate people, so economically, the owners of vehicles are sensitive to the durability and wear resistance of tires that can maintain and use the tires for a long time.

Currently, reinforcing fillers are used to reinforce the rubbers that make up a tire when manufacturing a tire.

Such reinforcing fillers mainly use carbon black and silica in addition to carbon black. However, carbon black is still used as a main reinforcing filler for various reasons including economical aspects.

In the production of tire rubbers such as treads and sidewalls using carbon black as a reinforcing filler, the unvulcanized elastomer with carbon black increases the viscosity and the smoothness during injection. Although a large specific surface area is mainly used to increase the bonding strength between the additive and the rubber except for the increase, the hardness, durability, and electrical conductivity of the vulcanized body including the carbon black increase as the specific surface area of the carbon black increases. However, in the case of using the carbon black filler having a large specific surface area as described above, due to the filler-filler interaction between the fillers, a high incidence of agglomeration between the fillers and a low processability are generated.

The present invention seeks to provide a tire tread rubber composition having increased workability and improved wear resistance.

In the tire tread rubber composition, the present invention not only increases the amount of bound rubber between rubber and filler by applying the surface treated carbon black, but also improves the dispersibility of the surface treated carbon black and improves the processability. This is to provide an increased tire tread rubber composition with improved wear resistance.

The present invention, in the rubber composition for tire tread, by applying the surface-treated carbon black to increase the amount of bound rubber between the rubber and the filler as well as improve the dispersibility of the surface-treated carbon black to improve the processability It is possible to provide a tire tread rubber composition that is increased and has improved wear resistance.

The present invention shows a tire tread rubber composition with improved processability and wear resistance.

The present invention, in the conventional tire tread rubber composition, 10 to 80 parts by weight of carbon black surface-treated with respect to 100 parts by weight of raw rubber, silica, titanium dioxide, clay, layered silicate ( 5-30 parts by weight of any one or more reinforcing fillers selected from the group of layered silicate, tungsten, talc, syndiotactic-1,2-polybutadiene (SPB) A tire tread rubber composition is shown.

In the present invention, the raw rubber in the conventional tire tread rubber composition may use any one or more rubber selected from the group of natural rubber and synthetic rubber.

In the tire tread rubber composition of the present invention, when the raw rubber is a mixed rubber in which two kinds of natural rubber and synthetic rubber are mixed, natural rubber and synthetic rubber may be mixed rubber mixed in a weight ratio of 1: 9 to 9: 1. Can be.

In the above, natural rubber means any one or more selected from the group of natural rubber and modified natural rubber.

Synthetic rubber is styrene butadiene rubber (SBR), modified styrene butadiene rubber, butadiene rubber (BR), chlorosulfonated polyethylene rubber, epichlorohydrin rubber, fluorine rubber, silicone rubber, trill 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, hypallon rubber, chloroprene rubber, ethylene vinyl Cetiate rubber, acrylic rubber, hydrin rubber, vinyl benzyl chloride styrene butadiene rubber, bromomethylstyrene butyl rubber, maleic acid styrene butadiene rubber, carboxylic acid styrene butadiene rubber, epoxy isoprene rubber, maleic acid ethylene propylene rubber, carboxylic acid nitrile Of butadiene rubber and brominated polyisobutyl isoprene-co-paramethyl styrene (BIMS) At least one selected from may be used.

As an example of the raw material rubber in the tire tread rubber composition of the present invention, styrene butadiene rubber (SBR) having a styrene content of 23 ± 0.5% may be used.

The tire tread rubber composition of the present invention may use 10 to 80 parts by weight of carbon black surface-treated with respect to 100 parts by weight of the raw rubber. If less than 10 parts by weight of carbon black surface-treated with respect to 100 parts by weight of raw material rubber, the role of carbon black as a reinforcing filler is insignificant, and more than 80 parts by weight of carbon black surface-treated with respect to 100 parts by weight of raw rubber. The carbon black treated with excess surface agglomerates with each other to reduce the dispersibility and the physical properties may be reduced. Therefore, the carbon black surface-treated in the tire tread rubber composition of the present invention is preferably used 10 to 80 parts by weight based on 100 parts by weight of the raw material rubber.

The carbon black surface-treated in the tire tread rubber composition of the present invention may use carbon black surface-treated by oxidizing carbon black to H ₃ PO ₄ in an electrolytic cell.

 The carbon black surface-treated in the tire tread rubber composition of the present invention may use carbon black surface-treated by oxidizing carbon black to NaOH in an electrolytic cell.

In the tire tread rubber composition of the present invention, the carbon black surface treated by oxidizing carbon black to H ₃ PO ₄ in the electrolytic cell and the carbon black surface treated by oxidizing carbon black to NaOH in the electrolytic cell can be used simultaneously. have.

Oxidizing the carbon black in an electrolytic cell as in the H ₃ PO ₄ is subjected to anodic oxidation in an electrolyte of 10~20wt% H ₃ PO _4, preferably from 10wt% H ₃ PO ₄ for 20 min for 10-30 minutes in the electrolytic cell The surface treated carbon black can be obtained. Meanwhile, before oxidizing the carbon black in the electrolytic cell, the carbon black may be washed one to three times in distilled water and then dried at a temperature of 70 to 90 ° C. for 24 to 48 hours to remove the carbon black.

Oxidation of carbon black to NaOH in the electrolytic cell may be anodic oxidation in an electrolyte of 10 to 20 wt% NaOH for 10 to 30 minutes, preferably 10 wt% NaOH in an electrolytic cell to obtain surface treated carbon black. . Meanwhile, before oxidizing the carbon black in the electrolytic cell, the carbon black may be washed one to three times in distilled water and then dried at a temperature of 70 to 90 ° C. for 24 to 48 hours to remove the carbon black.

The carbon black used to obtain the carbon black surface-treated above may be used having an iodine adsorption value of 90 to 120 mg / g.

Carbon black used to obtain the surface-treated carbon black can be used with a DBP adsorption value of 130 ~ 140 Pa / 100g.

The carbon black used to obtain the surface-treated carbon black can be used having an iodine adsorption value of 90 to 120 mg / g and a DBP adsorption value of 130 to 140 Pa / 100g.

The tire tread rubber composition of the present invention may be at least one reinforcing material selected from the group of silica, titanium oxide, clay, layered silicate, feldspar, talc, syndiotactic-1,2-polybutadiene (SPB) based on 100 parts by weight of raw rubber. 5 to 30 parts by weight of a filler may be used. If less than 5 parts by weight of any one or more reinforcing fillers selected from the group consisting of silica, titanium oxide, clay, layered silicate, barite, talc, syndiotactic-1,2-polybutadiene (SPB) The content as a reinforcing filler is low, so that the reinforcing property of the rubber composition can be reduced, and silica, titanium oxide, clay, layered silicate, bisulfite, talc, syndiotactic-1,2-polybutadiene (SPB) based on 100 parts by weight of the raw material rubber Using more than 80 parts by weight of any one or more reinforcing fillers selected from the group of) and by the use of excess reinforcing fillers the reinforcing fillers are agglomerated with each other to reduce the dispersibility and there is a fear that the physical properties. Therefore, in the tire tread rubber composition of the present invention, any one or more reinforcing fillers selected from the group consisting of silica, titanium oxide, clay, layered silicate, tungsten, talc, syndiotactic-1,2-polybutadiene (SPB) are 100 parts by weight of raw rubber. It is good to use 5-30 weight part with respect to.

In the above, the layered silicate may be one having an interlayer spacing of 0.1 to 10 nm.

In the above-described layered silicate, an aspect ratio (l / d) representing a ratio of the plane width l to the thickness d may be 5 or more.

In the above, the layered silicate may have a flat ratio of 5 to 100.

As the layered silicate, natural layered silicates capable of cation exchange and / or anion exchange may be used.

The layered silicate may be a synthetic layered silicate capable of cation exchange and / or anion exchange reaction.

The layered silicate may be an organic layered silicate organically treated with a material having a cationic group and / or a material having an anionic group.

The layered silicates are montmorillonite, saponite, hectorite, hectorite, rectorite, vermiculite, mica, illite, kaolinite, and kaolinite. Any one selected from the group of sodium montmorillonite (Na-MMT) and claisite 15A can be used.

In the above syndiotactic-1,2-polybutadiene (SPB) has a diameter of 0.01 to 0.1㎛, specific surface area of 80 to 90m ² / g or syndiotactic-1,2-polybutadiene (SPB) is A diameter of 1 to 10 µm and a specific surface area of 100 to 120 m ² / g can be used.

The present invention includes a rubber consisting of the tire tread rubber composition.

The present invention includes a tire containing a rubber composed of the tire tread rubber composition described above.

The present invention includes a tire containing the rubber made of the tire tread rubber composition as a tread.

The tire containing the rubber made of the tire tread rubber composition is at least one selected from the group of passenger car tires, truck tires, bus tires, motorcycle tires and aircraft tires.

In the tire tread rubber composition of the present invention, the tire tread rubber composition is applied under various conditions such as various components and contents. In order to achieve the object of the present invention, the tire tread rubber composition under the above-mentioned conditions is preferable.

The tire tread rubber composition according to the present invention may contain various additives such as activators, anti-aging agents, process oils, vulcanizing agents, and vulcanization accelerators, which are used in conventional tire tread rubber compositions, in addition to the above-mentioned raw rubber, surface treated carbon black, and reinforcing filler. If necessary, it can be used in a predetermined amount by appropriate selection. However, these are general components used in conventional tire tread rubber compositions, and thus are not essential components of the present invention, and thus the detailed descriptions thereof will be omitted.

Hereinafter, the present invention will be described by the following examples, comparative examples and test examples. However, these are not limited to the scope of the present invention by these as an embodiment of the present invention.

Comparative Example

Styrene butadiene rubber (SBR) having a styrene content of 23.5% is used as a raw material rubber, and 70 parts by weight of carbon black and an antioxidant (N-phenyl-N '-(1,3-dimethylbutyl) are used based on 100 parts by weight of the raw material rubber. -P-phenylenediamine, 6PPD) 2 parts by weight of zinc oxide, 2 parts by weight of zinc oxide and 2 parts by weight of stearic acid were added to a Banbury Mixer and blended to obtain a rubber compound.

After transferring the rubber compound to a roll mill, 2.0 parts by weight of sulfur as a vulcanizing agent and 2.0 parts by weight of cyclohexyl benzothiazol sulfenamide (CZ) as a vulcanizing accelerator were added and vulcanized at 160 ° C. for 20 minutes. Specimen was prepared.

In the carbon black, the iodine adsorption value of 115 mg / g and the DBP adsorption value of 135 cc / 100 g were used.

Table 1 summarizes the contents of the rubber composition.

<Example 1>

Styrene butadiene rubber (SBR) having a styrene content of 23.5% as raw material rubber, 70 parts by weight of carbon black surface-treated with respect to 100 parts by weight of the raw material rubber, antioxidant (6PPD) 2 parts by weight of zinc oxide, 2 parts by weight of zinc oxide, and 2 parts by weight of stearic acid were added to a Banbury mixer and blended to obtain a rubber compound.

After transferring the rubber compound to a roll mill, 2.0 parts by weight of sulfur as a vulcanizing agent and 2.0 parts by weight of cyclohexyl benzothiazole sulfenamide (CZ) as a vulcanization accelerator were added and vulcanized at 160 ° C. for 20 minutes to prepare a rubber specimen.

The surface treated carbon black (ACB) is an iodine adsorption value of 115 mg / g and a DBP adsorption value of 135cc / 100g after washing two times in distilled water carbon black 20 to dry at a temperature of 80 ℃ 20 What was obtained by carrying out anodization in an electrolyte of 10 wt% H ₃ PO ₄ for minutes was used.

Table 1 summarizes the contents of the rubber composition.

<Example 2>

Styrene butadiene rubber (SBR) having a styrene content of 23.5% as raw material rubber, 70 parts by weight of carbon black surface-treated with respect to 100 parts by weight of the raw material rubber, antioxidant (6PPD) 2 parts by weight of zinc oxide, 2 parts by weight of zinc oxide, and 2 parts by weight of stearic acid were added to a Banbury mixer and blended to obtain a rubber compound.

After transferring the rubber compound to a roll mill, 2.0 parts by weight of sulfur as a vulcanizing agent and 2.0 parts by weight of cyclohexyl benzothiazole sulfenamide (CZ) as a vulcanization accelerator were added and vulcanized at 160 ° C. for 20 minutes to prepare a rubber specimen.

The basic carbon black (BCB) surface-treated above was washed twice with distilled water in carbon black having an iodine adsorption value of 115 mg / g and a DBP adsorption value of 135 cc / 100 g, and then dried at a temperature of 80 ° C. for 20 hours. What was obtained by carrying out anodization in an electrolyte of 10 wt% NaOH for minutes was used.

Table 1 summarizes the contents of the rubber composition.

<Example 3>

Instead of using 70 parts by weight of surface treated carbon black, 35 parts by weight of surface treated carbon black (ACB) and 35 parts by weight of basic carbon black (BCB) are excluded. And the rubber sipin was prepared in the same manner as in Example 1.

Table 1 summarizes the contents of the rubber composition.

Table 1. Rubber composition of Comparative Examples and Examples 1 to 3 (unit: parts by weight)

division Comparative example Example 1 Example 2 Example 3 SBR 100 100 100 100 Carbon black 70 - - - ACB 0 70 - 35 BCB 0 0 70 35 Antioxidant (6PPD) 2 2 2 2 Zinc oxide 2 2 2 2 Stearic acid 2 2 2 2 sulfur 2 2 2 2 Vulcanization accelerator (CZ) 2 2 2 2

 <Test Example>

For each rubber specimen prepared in Comparative Examples and Examples 1, 2, and 3, the properties of Mooney, tensile properties, and abrasion were measured by ASTM-related regulations, and the results are shown in Table 2 below. It was.

Table 2. Comparative Example and Example Rubber Specimen Property Test Results

division Comparative example Example 1 Example 2 Example 3 Mooney Mooney viscosity t5 (min) 100 21 101 20 103 20 101 21 Tensile Properties Hardness 300% Modulus Tensile Strength Elongation 100 100 100 100 100 102 101 100 102 109 112 101 101 105 105 100 Wear DIN wear 100 105 113 107

* In Table 2, the values for Mooney (except t5), tensile properties, and wear of Examples 1 to 3 represent the converted values when the value of the comparative example is 100, and the higher the value, the better the physical properties. do.

As shown in the results of Table 2, the rubber specimens of Examples 1 to 3, which are made of a rubber composition to which the surface-treated carbon black is added, are used in the rubber specimens of the comparative examples, which are made of a rubber composition to which the surface-treated carbon black is not added. Compared with Mooney, tensile properties, mammoth properties are excellent. In particular, the carbon black (BCB) surface-treated by oxidation in NaOH electrolyte showed a 12% synergistic effect compared to the comparative example and 13% improvement compared to the comparative example in the DIN wear index. On the other hand, it can be seen that the physical properties for the viscosity is improved, the processability is also excellent.

As described above, those skilled in the art have been described with reference to the preferred embodiments of the present invention, various modifications and changes of the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It will be appreciated that it can be changed.

Claims (5)

In the tire tread rubber composition, 10 to 80 parts by weight of carbon black surface-treated with respect to 100 parts by weight of raw rubber, silica, titanium dioxide, clay, layered silicate, tungsten, and talc ( Talc), a tire tread rubber composition comprising 5 to 30 parts by weight of any one or more reinforcing fillers selected from the group of syndiotactic-1,2-polybutadiene (SPB). The carbon black of claim 1, wherein the surface treated carbon black is carbon black surface-treated through anodization with H ₃ PO ₄ in an electrolytic cell, or carbon black surface-treated with anodic oxidation with NaOH in an electrolytic cell. Tire tread rubber composition, characterized in that. The tire tread rubber composition according to claim 2, wherein the carbon black used to obtain the surface-treated carbon black has an iodine adsorption value of 90 to 120 mg / g and a DBP adsorption value of 130 to 140 Pa / 100g. Rubber consisting of the rubber composition of claim 1. A tire comprising a rubber comprising the rubber composition of claim 1.