KR20050081500A - Tread compound for tire including carbon black coated performance enhanced agent - Google Patents

Abstract

The present invention relates to a tread rubber composition for a tire. More specifically, in a tread rubber composition for a tire to which carbon black is applied as a reinforcing filler, the tire can be improved by including a carbon black coated with a performance enhancer. It relates to a tread rubber composition.

The present invention provides a tread rubber composition for tires that can improve wear resistance, tensile properties, braking force on wet roads, and rolling resistance by applying carbon black coated with a performance enhancer to improve the performance of carbon black. It is an object of the present invention to provide a tire comprising a rubber.

The tread rubber composition for tires of the present invention comprises 40 to 90 parts by weight of carbon black coated with a performance enhancer, based on 100 parts by weight of the raw material rubber in a known tread rubber composition for tires.

Description

Tread compound for tire including carbon black coated performance enhanced agent}

The present invention relates to a tread rubber composition for a tire. More specifically, in a tread rubber composition for a tire to which carbon black is applied as a reinforcing filler, the tire can be improved by including a carbon black coated with a performance enhancer. It relates to a tread rubber composition.

BACKGROUND ART In recent years, in rubbers used in tires, rubber compositions having excellent braking force and wet rolling resistance on wet roads as reinforcing fillers are used in combination with carbon black or silica alone. However, since silica has a strong hydrophilic group, the cohesiveness is high due to the interaction between silicas, and thus the dispersibility is low, and when used in a rubber composition, the viscosity may increase due to poor dispersion and gel property may be degraded due to gelation reaction for a long time. In order to solve the problem of silica, dispersing aids, process oils and coupling agents are used to improve the dispersibility of the silica. However, in spite of this treatment, the dispersibility of silica is low, which causes irregular wear phenomenon in the finished tire made of a rubber composition to which silica is applied.

On the other hand, when carbon black is used as a reinforcing filler in rubber compositions, the wear resistance of rubber is improved, but there is a problem in that braking force and rotational resistance characteristics on wet roads are lower than those of silica.

Generally, a silane coupling agent is applied to a rubber compound to apply silica to improve silica dispersibility, but a separate process aid is used to improve the dispersibility of carbon black and rubber to a rubber compound to which carbon black is applied. It is not.

The present invention focuses on the relationship between silica and silane coupling agent, and in the rubber compound applying carbon black as a reinforcing filler, the carbon black coated with a performance enhancer is applied to improve the performance of carbon black. An object of the present invention is to provide a tread rubber composition for a tire that can improve braking force and rolling resistance characteristics on a road surface.

In another aspect, the present invention is to provide a tire comprising a rubber made of the tire tread rubber composition.

In order to achieve the above-mentioned object of the present invention, the tire tread rubber composition of the present invention comprises 40 to 90 parts by weight of carbon black coated with a performance enhancer based on 100 parts by weight of the raw material rubber. do.

In the present invention, the raw material rubber can be used as long as it can be used as the raw material rubber of the conventional tire tread rubber composition. As an example of such raw rubber, in the present invention, synthetic rubber such as natural rubber, styrene butadiene rubber, butadiene rubber, styrene butadiene rubber containing isoprene, styrene butadiene rubber containing nitrile, and neoprene rubber may be used alone or two or more of them. Mixed rubber mixed with synthetic rubber can be used. In addition, it is possible to use a mixture of the natural rubber and synthetic rubber mixed in a ratio of 1: 9 to 9: 1. On the other hand, when the raw material rubber is composed of a mixture of two kinds of synthetic rubber, the two types of synthetic rubber can be used as the raw material rubber mixed rubber in a ratio of 1: 9 to 9: 1, respectively.

In the present invention, when less than 40 parts by weight of carbon black coated with a performance enhancer is used in the present invention, there is a problem that the physical properties of the rubber are deteriorated. Not. Therefore, the carbon black coated with a performance enhancer used as a reinforcing filler in the present invention is preferably applied to 40 to 90 parts by weight of carbon black.

In the rubber composition of the present invention, the performance enhancer coated on the carbon black may coat the carbon black with 2 to 6% of the carbon black content so as to maximize the performance of the carbon black. In the carbon black coated with a performance enhancer in the present invention, when the performance enhancer is coated with carbon black at less than 2% of the carbon black content, it is insignificant to exhibit the best performance of the carbon black. The coating of carbon black has no obvious effect of increasing the performance of the carbon black. Therefore, the carbon black performance enhancer in the present invention is preferably added 2 to 6% compared to the carbon black content.

In the carbon black coated with a performance enhancer in the present invention, any performance enhancer can be used as long as it can improve the performance of the carbon black to improve the physical properties of the rubber. In the present invention, as an example of the performance enhancing agent that can be coated on the carbon black, dibutyl xanthogen disulfide containing disulfide in the main chain may be used.

In the present invention, when the performance enhancer is coated on carbon black, the performance enhancer may be coated on carbon black at a high temperature of 170 ° C. or higher to increase the reactivity of the carbon black with rubber. By adding carbon black coated with a performance enhancer in the present invention, the content of bound rubber, which is a measure of reactivity with rubber, increases the tensile properties and rebound performance of the rubber while lowering heat generation, abrasion resistance, braking force on wet roads, and rotation. The resistance characteristic can be improved.

According to the present invention, 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 rubbers and carbon blacks coated with performance enhancing agents are appropriately selected. It can be used in a predetermined content. 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.

On the other hand, the present invention includes a tire containing a rubber made of the tire tread rubber composition. In this case, the tire includes any one selected from tires for automobiles, tires for trucks, and tires for buses.

Hereinafter, the present invention will be described by the following comparative examples, 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

72 parts by weight of carbon black (N330), 2.5 parts by weight of zinc, 2.5 parts by weight of stearic acid, and an anti-aging agent based on 100 parts by weight of a raw material rubber composed of 75 parts by weight of solution-polymerized styrene butadiene rubber (SBR) and 25 parts by weight of butadiene rubber (BR). Kumanox-RD, Kumho Petrochemical) 2.0 parts by weight were placed in a Banbury mixer and reacted at 170 ° C. for 30 minutes to obtain a primary blend. In the primary formulation, 2.0 parts by weight of sulfur and 1.5 parts by weight of vulcanization accelerator (N-cyclohexyl-2-benzothiazolsulfen amide, CZ) were placed in a Banbury mixer and vulcanized at 100 ° C. for 20 minutes to prepare a rubber.

<Example>

A rubber was manufactured using the same composition and method as in Comparative Example except that 72 parts by weight of carbon black coated with a performance enhancer was added.

In the above performance enhancer was used a dibutyl xanthogen disulfide (DXD) having a disulfide in the main chain, the carbon black coated with a performance enhancer 3.0% of the carbon black weight to the carbon black at 170 ℃ Was used.

Table 1. Composition of Comparative Example and Example (unit: parts by weight)

Item Comparative example Example Styrene Butadiene Rubber 75 75 Butadiene rubber 25 25 Carbon black 72 - Carbon black * - 72 Zincification 2.5 2.5 Stearic acid 1.0 1.0 Anti-aging 2.0 2.0 Process oil 4.0 4.0 brimstone 2.0 2.0 Vulcanization accelerator 1.5 1.5

* Carbon black coated with 3% performance enhancer based on carbon black weight

<Test Example>

Viscosity, scorch time, vulcanization time, hardness, 300% modulus, tensile strength, elongation, heat generation, rebound, glass transition temperature (Tg), and dynamic viscoelasticity (Tanδ (0 ° C.)) for the rubbers of the comparative examples and examples. , Tanδ (70 ° C.), Dean wear, and bound rubber content were measured by ASTM-related regulations and the results are shown in Table 2 below.

Table 2. Physical Properties of Comparative Examples and Examples

Item Comparative example Example Viscosity (100 ° C) 68 70 Scorch time (t5) 15.3 6.0 Rush time (t90) 11.5 10.8 Shore A 65 66 300% modulus (kgf / cm ² ) 129 194 Tensile strength (kgf / cm ² ) 189 203 % Elongation 420 210 Fever (temperature difference) 25 16 Rebound (1st) 35.4 43.7 Tanδ (0 ° C) * 0.371 0.427 Tanδ (70 ° C) * 0.273 0.179 Dinmamo (Index) 100 108 Bound rubber content (%) ** 43 78

* Dynamic viscoelasticity (Tan δ): Measured by changing the temperature at 11Hz, 1.25% strain condition using the Leohebron test (Rheovibron test) and the value is shown. The larger the value of Tanδ (0 ° C), the better the braking performance on wet road surfaces. In addition, the smaller the value of Tanδ (70 ℃) shows a lower rotational resistance, which means that the rotational resistance characteristics are excellent.

** Indicates a measure of reactivity between carbon black and rubber.

As shown in Table 2, which is the result of the test example, it can be seen that the example rubber prepared by the rubber composition of the present invention has improved tensile properties such as 300% modulus and tensile strength compared to the rubber of the comparative example prepared by the conventional rubber composition. In addition, heat generation and rebound characteristics are improved, and even in the dynamic viscoelastic properties, the value of Tanδ (0 ° C.) is high, so the braking force is excellent on wet roads, and the value of Tanδ (70 ° C.) is low, low rolling resistance, It can be seen that it is significantly improved.

In addition, it can be seen that the rubber and carbon black have excellent mutual reactivity due to the high content of bound rubber, which is a measure of the reactivity between carbon black and rubber.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and modified within the scope of the present invention without departing from the spirit and scope of the present invention described in the claims below. It will be appreciated that it can be changed.

Claims (4)

In the tread rubber composition for tires, A tread rubber composition for tires, comprising 40 to 90 parts by weight of carbon black coated with a performance enhancer based on 100 parts by weight of raw rubber. The tread rubber composition for a tire according to claim 1, wherein the performance enhancer is used in an amount of 2 to 6% by weight of carbon black. The tread rubber composition for a tire according to claim 1, wherein the performance enhancer is dibutyl xanthogen disulfide containing disulfide in the main chain. A tire comprising a rubber consisting of a tread rubber composition for tires according to claim 1.