KR20090096250A - Insert rubber composition to reinforce the sidewall of run-flat tire - Google Patents

Abstract

A rubber composition for reinforcing the sidewall of a run flat tire, a rubber comprising the composition, and a run flat tire containing the rubber are provided to improve mechanical property, to reduce the content of a filler and to enhance the heat build-up of rubber. A rubber composition for reinforcing the sidewall of a run flat tire comprises 100 parts by weight of a raw rubber which comprises 40~95 parts by weight of a natural rubber, and 5~60 parts by weight of a styrene-butadiene rubber comprising 10~20% of a styrene content and 55~80% of a vinyl content; and 30~60 parts by weight of a reinforcing filler. The reinforcing filler is at least one selected from the group consisting of carbon black, silica, titanium dioxide, clay, layered silicate, tungsten, talc, and syndiotactic-1,2-polybutadiene.

Description

Insert rubber composition to reinforce the sidewall of run-flat tire}

The present invention relates to a rubber composition for reinforcing sidewalls of a run-flat tire, and more particularly, to a rubber composition for reinforcing sidewalls of a run-flat tire, which is a rubber composition that is reinforced on a sidewall of a run-flat tire. A styrene butadiene rubber containing 40 to 95 parts by weight of natural rubber, low styrene and high vinyl, preferably 5 to 60 styrene butadiene rubber having a styrene content of 10 to 20% and a vinyl content of 55 to 80%. The present invention relates to a rubber composition for reinforcing sidewalls of run-flat tires, including 30 to 60 parts by weight of reinforcing fillers, based on 100 parts by weight of raw material rubber.

Run-flat tires are tires that can travel a certain distance without air pressure by inserting a structure or reinforcement sidewall inside the tire.

Run-flat tires allow the vehicle to move without the need for tire pressure, so spare tires do not need spare tires that are always stored in the vehicle, helping to lighten the vehicle's weight, making it suitable for high-speed driving in sports cars and some luxury sedans. In addition, since it enables relatively stable driving even when the tires are damaged at high speeds, it is recently installed in mass production vehicles.

Unlike the advantages of run-flat tires as described above, the disadvantages of current run-flat tires are that they are expensive and have more noise than ordinary tires. However, these problems can be solved as technology develops. Demand for run-flat tires is expected to increase.

In general, various additives are used in rubber for tires to improve physical properties. For example, reinforcing fillers are used for the reinforcement of rubber, and carbon black and / or silica are mainly used as reinforcing fillers used in tires. Recently, in addition to such carbon black and silica, various reinforcing filler components including clays are often used as reinforcing agents.

The present invention provides a styrene-butadiene rubber (SBR) having a low content of styrene and a high vinyl in the raw material rubber to excellent mechanical properties, in particular, a run-flat tire that can improve the heat generation characteristics of the rubber to reduce the content of the filler To provide a rubber composition for sidewall reinforcement of the rubber composition, the rubber composition made of the rubber composition and / or rubber pleats made of the rubber composition.

The present invention relates to a rubber composition for reinforcing the sidewall of a runflat tire, which is a rubber composition that is reinforced to the sidewall of a runflat tire, comprising 40 to 95 parts by weight of natural rubber, styrene butadiene containing a high content of styrene and a high content of vinyl. 30 to 60 parts by weight of reinforcing fillers are included with respect to 100 parts by weight of rubber, preferably 5 to 60 parts by weight of styrene butadiene rubber having a styrene content of 10 to 20% and a vinyl content of 55 to 80%. An object of the present invention is to provide a rubber composition for reinforcing sidewalls of a run flat tire.

The present invention is to include styrene butadiene rubber (SBR) having a low content of styrene and a high vinyl in the raw material rubber to excellent mechanical properties, in particular, the run-flat that can improve the heat generation characteristics of the rubber to reduce the content of the filler It is possible to provide a run flat tire comprising a rubber composition for reinforcing sidewalls of a tire, rubber made of the rubber composition, and / or rubber made of the rubber composition.

The present invention represents a rubber composition for reinforcing sidewalls of run-flat tires that can improve heat generation properties and tensile properties.

In the rubber composition for reinforcing the sidewall of a run flat tire, the present invention comprises: 40 to 95 parts by weight of natural rubber, 5 to 60 parts by weight of styrene butadiene rubber having a styrene content of 10 to 20% and a vinyl content of 55 to 80%. The rubber composition for sidewall reinforcement of a run flat tire comprising 30 to 60 parts by weight of a reinforcing filler based on 100 parts by weight of rubber.

When using natural rubber which is one of the components constituting the raw rubber in the sidewall reinforcement rubber composition of the run flat tire of the present invention in less than 40 parts by weight of 100 parts by weight of raw rubber, due to the excellent tensile and tear strength retention of natural rubber It is not possible to achieve an effective improvement of the performance, and when using more than 95 parts by weight of natural rubber, the content of styrene butadiene rubber (SBR) having a low content of styrene and a high content of vinyl, which is another component of the raw material rubber is small for the purpose of the present invention There is a problem that is difficult to obtain a matching effect.

In the rubber composition for sidewall reinforcement of the run flat tire of the present invention, one of the components constituting the raw material rubber has a low content of styrene and a high content of vinyl, preferably a styrene content of 10 to 20% and a vinyl content of 55 to 80 % Styrene butadiene rubber (SBR) does not achieve the desired performance improvement of the present invention when using less than 5 parts by weight of raw material rubber, the relative decrease of the natural rubber content when used in excess of 60 parts by weight, Due to the increased content of the SBR there is also a problem that does not have the best performance in accordance with the object of the present invention.

Therefore, in the rubber composition for sidewall reinforcement of the run flat tire of the present invention, the raw material rubber has 40 to 95 parts by weight of natural rubber, low styrene and high vinyl content among 100 parts by weight of raw rubber, and preferably 10 to 20 styrene. %, It is preferable to use the one consisting of 5 to 60 parts by weight of styrene butadiene rubber having a vinyl content of 55 to 80%.

The rubber composition for reinforcing sidewalls of the run flat tire of the present invention may use a reinforcing filler for improving physical properties including reinforcing properties of the rubber composition.

In the rubber composition for sidewall reinforcement of the run flat tire of the present invention, the reinforcing filler may be used in an amount of 30 to 60 parts by weight based on 100 parts by weight of the above-mentioned raw rubber.

In the rubber composition for sidewall reinforcement of the run flat tire of the present invention, when the reinforcing filler is used less than 30 parts by weight based on 100 parts by weight of the above-mentioned raw rubber, the rubber properties are not good due to the low filling effect, and 60 parts by weight. When used in excess, there is a limit in obtaining the desired rubber properties in the present invention due to excessive hardness and modulus rise, and there is a problem in poor work performance even in the post process such as compounding and extrusion.

Therefore, in the rubber composition for reinforcing the sidewall of the run flat tire of the present invention, the reinforcing filler is preferably used in an amount of 30 to 60 parts by weight based on 100 parts by weight of the raw material rubber.

The reinforcing fillers are carbon black, silica, titanium oxide, clay, layered silicate, tungsten, talc, syndiotactic- Any one or more selected from the group of 1,2-polybutadiene (syndiotactic-1,2-polybutadiene, SPB) may be used.

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.

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

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) may have a diameter of 0.01 to 0.1 µm and a specific surface area of 80 to 90 m ² / g.

In the above, syndiotactic-1,2-polybutadiene (SPB) has a diameter of 1 to 10 µm and a specific surface area of 100 to 120 m ² / g.

The present invention includes a rubber made of the rubber composition for sidewall reinforcement of the run-flat tire.

The present invention includes a tire containing a rubber made of a rubber composition for sidewall reinforcement of the run-flat tire.

The present invention includes a run flat tire containing a rubber made of a rubber composition for side wall reinforcement of the run flat tire for reinforcing the side wall.

The lot flat tire containing the rubber made of the rubber composition for sidewall reinforcement of the run flat tire is a run flat tire for a passenger car, a run flat tire for a truck, a run flat tire for a bus, a run flat tire for a motorcycle, and an run flat for an aircraft. Any one or more selected from the group of tires.

In the rubber composition for the sidewall reinforcement of the run flat tire of the present invention, the rubber composition for the sidewall reinforcement of the runflat tire is applied according to various components, contents, and the like, in order to achieve the object of the present invention mentioned above. Rubber compositions for reinforcing sidewalls of run-flat tires under one condition are preferred.

The rubber composition for sidewall reinforcement of the run flat tire of the present invention is an active agent, an anti-aging agent, a process oil, a vulcanizing agent, a vulcanization agent used in the sidewall reinforcement rubber composition of the conventional run flat tire, in addition to the above-mentioned raw rubber and reinforcing filler. Various additives, such as an accelerator, can be suitably selected and used in predetermined content as needed. However, these are general components used in the rubber composition for sidewall reinforcement of conventional run flat tires, and thus are not essential components of the present invention.

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

55 parts by weight of carbon black (N550), 10 parts by weight of silica (Z-175), coupling agent (X-50S) based on 100 parts by weight of the raw material rubber consisting of 80 parts by weight of natural rubber (NR) and 20 parts by weight of butadiene rubber (BR). ) 1.5 parts by weight, paraffin oil 3 parts by weight, zinc oxide 3 parts by weight, stearic acid 2 parts by weight, activator (Activator-73A, Strucktol) 3 parts by weight, anti-aging agent (Kumanox-13, Kumho Petrochemical) 2.5 parts by weight, adhesive 2.5 parts by weight of (B-18-S) was placed in a Banbury mixer and mixed at 140 ° C. for 30 minutes to obtain a rubber compound.

6 parts by weight of vulcanizing agent, 1.5 parts by weight of vulcanization accelerator (NS), 0.2 parts by weight of vulcanization retardant (PVI) were added to the rubber compound, and vulcanized at 150 ° C. for 20 minutes to prepare a rubber specimen.

Table 1 below shows the components of the rubber specimens together.

<Example 1>

55 parts by weight of carbon black (N550), silica (Z) based on 100 parts by weight of raw rubber consisting of 60 parts by weight of natural rubber (NR), 40 parts by weight of styrene butadiene rubber (SBR) having 18% styrene and 62% vinyl. 175) 10 parts by weight, 1.5 parts by weight of coupling agent (X-50S), 2 parts by weight of dispersant, 3 parts by weight of paraffin oil, 3 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 3 parts by weight of activator (Activator-73A, Strucktol) Part, 2.5 parts by weight of anti-aging agent (Kumanox-13, Kumho Petrochemical), 1.5 parts by weight of adhesive (Dyphene-8318), 2.5 parts by weight of adhesive (B-18-S) were placed in a Banbury mixer and mixed at 140 ° C. for 30 minutes. A rubber compound was obtained.

6 parts by weight of vulcanizing agent, 3.0 parts by weight of vulcanization accelerator (NS), 0.2 parts by weight of vulcanization retardant (PVI) were added to the rubber compound, and vulcanized at 150 ° C. for 20 minutes to prepare a rubber.

Table 1 below shows the components of the rubber specimens together.

<Example 2>

A rubber was manufactured in the same manner as in Example 1, except that 50 parts by weight of carbon black was used.

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

Item Comparative example Example 1 Example 2 Natural Rubber (NR) 80 60 60 Butadiene rubber (BR) 20 - - Styrene Butadiene Rubber (SBR) - 40 40 Carbon black 55 55 50 Silica 10 10 10 Coupling Agent (X-50S ^{1 )} ) 1.5 1.5 1.5 Activator ^{2 )} 3 3 3 Zinc oxide 4 4 4 Stearic acid 2 2 2 Antioxidant ^{3 )} 2.5 2.5 2.5 Wax One One One Process oil 2 2 2 B-18S 2.5 2.5 2.5 Vulcanizing agent ^{4 )} 6 6 6 Vulcanization accelerator (NS) 1.5 3.0 3.0

1) X-50S: Bis- (3-tridthoxysilylpropyl) tetrasulfide

Activator-73A: Mixture of zinc salts of alipathic and aromatic carboxylic acids (Product of Strucktol company)

Kumanox-13: N- (1,3-dimethylbutyl) -N-Phenyl-P-Phenylenediamine

4) Insoluble sulfur (80%) + Process Oil (20%)

* B-18-S: Resorcinol Formaldehyde Resin

* NS: N-tert-butyl-2-benzothiazolesulfenamide

<Test Example>

Rubber specimens prepared in Examples and Comparative Examples according to ASTM-related regulations, hardness, 100% modulus, tensile strength, elongation tensile properties, Mooney viscosity, heat built up (HBU) And blow-out properties were measured and the results are summarized in Table 2 below.

Table 2. Comparative Examples and Examples Properties of Rubber Specimens

Properties Comparative example Example 1 Example 2 Tensile Properties Hardness (ShoreA method) 100 110 100 100% Modulus (kg / ㎠) 100 120 110 Tensile Strength (kg / ㎠) 100 110 105 Elongation (%) 100 103 100 Mooney viscosity 100 95 90 Fever 100 96 95 Blowout 100 105 102

* Physical properties such as hardness, 100% modulus, tensile strength, elongation, tensile viscosity, Mooney viscosity, heat generation (HBU), blow-out, etc. of Examples 1 and 2 were set to 100 in Comparative Example. When the converted value is the value rounded off to the first decimal place, the Mooney viscosity and the exothermic properties of the lower value is excellent, the higher the value means that the higher the value.

* Mooney viscosity was measured using a Mooney (MOONEY) viscometer, the lower the viscosity indicates the superior processability.

* Heat generation (H.B.U.) is a value measured using an exothermic tester. The smaller the value, the better the heat resistance.

* Blow-Out test was measured using the B.F. Goodrich Blow-Out Test, and the longer the blow-out time, the better the heat resistance.

As shown in the results of Table 2, the rubber having low styrene and high vinyl content of the present invention, preferably a styrene butadiene rubber (SBR) having a styrene content of 10 to 20% and a vinyl content of 55 to 80% is included in the raw material rubber. The rubber of Examples 1 and 2 composed of the composition has a low content of styrene and a high content of vinyl, preferably a rubber containing no styrene butadiene rubber (SBR) having a styrene content of 10 to 20% and a vinyl content of 55 to 80%. Compared to the rubber of the comparative example made of the composition, the properties of the hardness, 100% modulus, tensile strength, elongation, tensile properties, Mooney viscosity, exothermic (HBU), blow-out (Blow-out), etc. The rubber composition for reinforcing the sidewall of the flat tire has excellent mechanical properties and improved heat generation characteristics.

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 (4)

In the rubber composition for reinforcing the sidewall of the run flat tire, It comprises 30 to 60 parts by weight of reinforcing fillers based on 100 parts by weight of the raw material rubber consisting of 40 to 95 parts by weight of natural rubber, 10 to 20% of styrene, and 5 to 60 parts by weight of styrene butadiene rubber having a vinyl content of 55 to 80%. Rubber composition for sidewall reinforcement of run flat tires. The method of claim 1, wherein the reinforcing filler is carbon black, silica, titanium dioxide, clay, layered silicate, tungsten, talc, Tire tread rubber composition, characterized in that any one or more selected from the group of syndiotactic-1,2-polybutadiene (SPB). In the above, syndiotactic-1,2-polybutadiene (SPB) has a diameter of 0.01 to 0.1 µm and a specific surface area of 80 to 90 m ² / g, or a diameter of 1 to 10 µm and a specific surface area of 100 to 120 m ^2. / g. Rubber consisting of the rubber composition of claim 1. A run flat tire comprising a rubber comprising the rubber composition of claim 1.