KR-20260062343-A - Rubber composition for shoe outsole with improved fluidity

Abstract

The present invention relates to a rubber composition for shoe outsoles with improved fluidity, and more specifically, to a rubber composition for shoe outsoles with improved fluidity that provides excellent mechanical properties by improving the fluidity of recycled rubber and thereby enhancing compatibility between general-purpose rubber and recycled rubber. The present invention provides a rubber composition for shoe outsoles with improved fluidity, characterized in that the rubber composition is formed using recycled rubber that has been desulfurized after crushing waste rubber, and comprises 100 parts by weight of a rubber base comprising 20 to 50 parts by weight of recycled rubber and 30 to 40 parts by weight of styrene-butadiene rubber, which is a general-purpose rubber, and 1 to 5 parts by weight of a processing aid comprising a metal salt, a fatty acid, and an alcoholamine, thereby improving the fluidity of the recycled rubber and improving the compatibility between the recycled rubber and the general-purpose rubber.

Inventors

• 오진현

Assignees

• ㈜핀프로젝트코리아

Dates

Publication Date

20260507

Application Date

20241029

Claims (1)

1. A rubber composition for a shoe outsole using recycled rubber that has been desulfurized after crushing waste rubber, wherein the composition comprises 1 to 5 parts by weight of a processing aid comprising a metal salt, a fatty acid, and an alcoholamine, based on 100 parts by weight of a rubber base comprising 20 to 50 parts by weight of the recycled rubber and 30 to 40 parts by weight of styrene-butadiene rubber, which is a general-purpose rubber, thereby improving the fluidity of the recycled rubber and improving the compatibility between the recycled rubber and the general-purpose rubber.

Description

Rubber composition for shoe outsole with improved fluidity The present invention relates to a rubber composition for shoe outsoles with improved fluidity, and more specifically, to a rubber composition for shoe outsoles with improved fluidity that provides excellent mechanical properties by improving the fluidity of recycled rubber and thereby enhancing compatibility between general-purpose rubber and recycled rubber. Recently, as the number of registered automobiles in Korea increases every year, the amount of waste rubber generated from waste tires is also increasing annually. Most of this waste rubber does not decompose naturally and does not rot, and it is also the cause of environmental pollution that contaminates the soil and air. Therefore, environmental problems caused by waste rubber have recently emerged throughout society. Accordingly, there have been attempts to solve environmental problems by using waste rubber as an energy source for cement production or combined heat and power generation, but due to the high cost burden, this has not been a practical solution. Therefore, research on ways to solve environmental problems by recycling waste rubber is continuously being raised. For example, there are methods of recycling waste rubber by turning it into small particle powder or rubber chips, and methods of recycling it by undergoing a desulfurization process to remove sulfur bound to the waste rubber. At this time, recycled rubber that has undergone a desulfurization process is mainly used in fields that do not require many physical properties, such as parking stoppers and floor cushioning materials, but when applied in excess to shoe outsoles, the physical properties deteriorate significantly and it is difficult to control mechanical properties, so it has not yet been commercialized in the shoe outsoles field. The 'Method for manufacturing a shoe outsole using waste rubber (Registration No.: 10-0187496)' relates to a method for manufacturing a shoe outsole by mixing general-purpose rubber and recycled rubber. It aimed to improve the physical properties of the shoe outsole by using a mixture of a sulfur crosslinking mechanism and a peroxide crosslinking mechanism. However, when the sulfur crosslinking mechanism and the peroxide crosslinking mechanism are used simultaneously, there is a problem that it is difficult to resolve the fundamental incompatibility between general-purpose rubber and recycled rubber, and there is a problem that the crosslinking time actually increases, resulting in poor productivity. Therefore, there is an urgent need for technological development to realize the high added value of waste rubber by utilizing waste rubber generated from waste tires as recycled rubber and improving its compatibility with general-purpose rubber. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. That is, the present invention relates to a rubber composition for shoe outsoles using recycled rubber that has been desulfurized after crushing waste rubber generated from waste tires, etc., and comprises, for every 100 parts by weight of a rubber base including recycled rubber and general-purpose rubber, 30 to 50 parts by weight of silica, 2 to 5 parts by weight of a silane coupling agent, 3 to 7 parts by weight of a metal oxide, 1 to 3 parts by weight of stearic acid, 1 to 3 parts by weight of an anti-aging agent, 1 to 5 parts by weight of a surfactant, 2 to 5 parts by weight of a process oil, 0.5 to 1.2 parts by weight of a crosslinking agent, and 0.5 to 1.2 parts by weight of a crosslinking accelerator, and further comprises 1 to 5 parts by weight of a processing aid consisting of one or more of a metal salt, a fatty acid, and an alcoholamine, thereby improving the fluidity of the recycled rubber and thus improving compatibility with general-purpose rubber. The rubber substrate of the present invention is configured to include 20 to 50 parts by weight of recycled rubber and 50 to 80 parts by weight of general-purpose rubber as the majority of the components constituting the rubber composition for shoe outsoles. First, recycled rubber refers to waste rubber generated from waste tires, etc., that has been crushed and then desulfurized. When forming a rubber base, if it is included in an amount of less than 20 parts by weight, it is not meaningful for reducing manufacturing costs, and if it is included in an amount exceeding 50 parts by weight, it cannot satisfy the mechanical properties required for shoe outsoles. Therefore, it is desirable to include it in the range of 20 to 50 parts by weight in the rubber base. Second, general-purpose rubber refers to rubber that can be commonly used when manufacturing shoe outsoles, and can be formed by including one or more of natural rubber, butadiene rubber and styrene-butadiene rubber in a range of 50 to 80 parts by weight. Among general-purpose rubbers, natural rubber has excel