KR-20260062169-A - METHOD FOR PREPARING HIGH QUALITY RECYCLED EPDM RUBBER

Abstract

One embodiment of the present specification provides a method for manufacturing recycled EPDM rubber, comprising: (a) a step of desulfurizing waste EPDM rubber; (b) a step of stirring the product of step (a) at a temperature of 40 to 100 ℃; and (c) a step of manufacturing the product of step (b) into pellets.

Inventors

• 이무정
• 이원희
• 최한활
• 최성현
• 김문수

Assignees

• (주)화승코퍼레이션
• (주)리앤알테크

Dates

Publication Date

20260507

Application Date

20241025

Claims (11)

1. (a) A step of desulfurizing waste EPDM rubber; (b) a step of stirring the product of step (a) at a temperature of 40 to 100 ℃; and (c) a step of forming the product of step (b) into pellets; comprising a method for manufacturing recycled EPDM rubber.
2. In paragraph 1, The above step (a) is, A method for manufacturing recycled EPDM rubber, further comprising the step of mixing desulfurized waste EPDM rubber with one selected from the group consisting of new EPDM, stearic acid, zinc oxide, polyethylene glycol, light carbon, carbon black, paraffin oil, vulcanization accelerator, sulfur, and combinations of two or more of these.
3. In paragraph 1, The above step (a) is, A method for manufacturing recycled EPDM rubber, further comprising the step of extruding desulfurized waste EPDM rubber.
4. In paragraph 1, A method for manufacturing recycled EPDM rubber, wherein step (b) above is performed under a pressure of 3 to 8 kgf/ cm² .
5. In paragraph 1, The above step (b) is, A method for producing recycled EPDM rubber, performed by adding a polyolefin elastomer to the product of step (a) above.
6. In paragraph 5, A method for manufacturing recycled EPDM rubber, wherein the above polyolefin elastomer is a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.
7. In paragraph 5, A method for manufacturing recycled EPDM rubber, wherein the amount of the polyolefin elastomer added is 5 to 35 parts by weight per 100 parts by weight of the product of step (a).
8. In paragraph 1, The above step (b) is, A method for manufacturing recycled EPDM rubber, performed by adding a deodorizing agent to the product of step (a) above.
9. In paragraph 8, A method for manufacturing recycled EPDM rubber, wherein the deodorizing agent is one selected from the group consisting of diatomaceous earth, alumina, sodium oxide, and a combination of two or more of these.
10. In paragraph 8, A method for manufacturing recycled EPDM rubber, wherein the amount of the deodorizing agent added is 1 to 20 parts by weight per 100 parts by weight of the product of step (a).
11. In paragraph 1, A method for manufacturing recycled EPDM rubber, wherein the average size of the pellets is 2 to 4 mm.

Description

Method for Preparing High Quality Recycled EPDM Rubber This specification relates to a method for manufacturing high-quality recycled EPDM rubber. Recently, as global warming and environmental pollution issues have become increasingly serious, interest in the treatment of industrial waste has been growing, and interest in the recycling of petrochemical products is rising worldwide. However, due to their cross-linked structure, rubber materials are relatively difficult to recycle compared to general plastics, so they are primarily disposed of through methods such as incineration or landfilling. EPDM (Ethylene Propylene Diene Monomer), also known as ethylene propylene rubber, is a high-performance synthetic rubber obtained by copolymerizing ethylene, propylene, and a diene that functions as a crosslinking site. EPDM rubber has excellent heat resistance, ozone resistance, and chemical resistance, and is used in various fields such as automotive body seals, tire tubes, hoses, washing machine gaskets, electrical wires, and construction materials. Meanwhile, used EPDM rubber products or EPDM rubber scrap generated during the rubber production process were conventionally classified as byproduct waste and treated as difficult to recycle due to the large amount of additives used in the vulcanization process. Consequently, waste EPDM rubber was primarily disposed of by incineration, but this method posed problems by causing water and air pollution. Consequently, although attempts were made to recycle waste EPDM rubber, recycled EPDM rubber produced using waste EPDM exhibited inferior mechanical properties, processability, and workability compared to conventional EPDM rubber. Furthermore, while a desulfurization process is required for recycling waste EPDM rubber, recycled EPDM rubber produced through this process suffered from odor issues caused by severed sulfur bonds. Therefore, there is a need to develop a method for manufacturing recycled EPDM rubber that utilizes waste EPDM rubber while maintaining excellent mechanical properties, processability, and workability, and simultaneously resolving the odor problem. Hereinafter, one aspect of this specification will be described based on specific examples. However, the details described in this specification may be implemented in various different forms and are therefore not limited to the embodiments described herein. Throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but rather allows for the inclusion of additional components. When a range of numerical values is described in this specification, unless a specific range is otherwise described, the value has the precision of significant figures provided according to the standard rules in chemistry for significant figures. For example, 10 includes a range of 5.0 to 14.9, and the number 10.0 includes a range of 9.50 to 10.49. Method for manufacturing recycled EPDM rubber A method for manufacturing recycled EPDM rubber according to one aspect of the present specification comprises: (a) a step of desulfurizing waste EPDM rubber; (b) a step of stirring the product of step (a) at a temperature of 40 to 100 ℃; and (c) a step of manufacturing the product of step (b) into pellets. The above method for manufacturing recycled EPDM rubber is environmentally friendly by using waste EPDM (Ethylene Propylene Diene Monomer) rubber, and by performing the mixing and dispersion process through stirring in step (b) and the pelletizing process in step (c), the viscosity of the rubber is lowered, thereby enabling the production of upcycled recycled EPDM rubber with excellent processability and workability. The above waste EPDM rubber may be used EPDM rubber products or EPDM rubber scrap generated from the rubber production process. The desulfurization treatment of step (a) above can be carried out by an extrusion desulfurization machine. Here, the compression desulfurization machine performs desulfurization treatment by using a screw extruder, which is a mechanical heating means, to shear and heat the waste EPDM rubber to raise the temperature to a level where sulfur crosslinking bonds can be severed. As a compression type desulfurizing machine, a single-screw extruder is suitable, but it is preferable to use a multi-screw extruder, such as a two-screw extruder, which can stably perform desulfurization by shear heating. The desulfurization treatment of step (a) above may be performed at a temperature of 200 to 500 ℃. For example, it may be performed at 200℃, 210℃, 220℃, 230℃, 240℃, 250℃, 260℃, 270℃, 280℃, 290℃, 300℃, 310℃, 320℃, 330℃, 340℃, 350℃, 360℃, 370℃, 380℃, 390℃, 400℃, 410℃, 420℃, 430℃, 440℃, 450℃, 460℃, 470℃, 480℃, 490℃, 500℃, or at a temperature between two of these temperatures. A method for manufacturing recycled EPDM rubber according to one aspect of the present specification may further include, pr