EPDM vs. Natural Rubber

Attribute	EPDM	Natural Rubber
Chemical Structure	Terpolymer of ethylene, propylene, and a diene monomer	Polymer of isoprene
Temperature Range	-50°C to 150°C	-50°C to 80°C
Weather Resistance	Excellent	Good
Oil Resistance	Good	Poor
Abrasion Resistance	Good	Excellent

Introduction

EPDM (Ethylene Propylene Diene Monomer) and natural rubber are two popular materials used in various industries for their unique properties. While both materials have their own advantages and disadvantages, understanding the differences between them can help in choosing the right material for a specific application.

Physical Properties

EPDM is a synthetic rubber that is known for its excellent resistance to weathering, ozone, and UV exposure. It also has good resistance to heat, water, and steam. On the other hand, natural rubber is derived from the latex of rubber trees and is known for its high elasticity and resilience. It has good tear strength and abrasion resistance.

Chemical Resistance

EPDM has good resistance to a wide range of chemicals, including acids, alkalis, and polar solvents. It is not recommended for use with oils and hydrocarbons, as it can swell and degrade in these environments. Natural rubber, on the other hand, has poor resistance to most chemicals and is not suitable for applications where exposure to chemicals is a concern.

Temperature Resistance

EPDM has a higher temperature resistance compared to natural rubber. It can withstand temperatures ranging from -50°C to 150°C, making it suitable for outdoor applications where exposure to extreme temperatures is a concern. Natural rubber, on the other hand, has a lower temperature resistance and can degrade at high temperatures.

Mechanical Properties

EPDM has good tensile strength, elongation, and tear resistance, making it suitable for applications where durability and flexibility are important. Natural rubber also has good tensile strength and elongation, but it is more prone to abrasion and wear compared to EPDM. EPDM is also more resistant to aging and weathering compared to natural rubber.

Applications

EPDM is commonly used in roofing membranes, automotive seals, weatherstripping, and gaskets due to its excellent weather resistance and durability. Natural rubber is often used in tires, conveyor belts, hoses, and footwear due to its high elasticity and resilience. Both materials have their own specific applications where their unique properties are beneficial.

Cost

EPDM is generally more expensive than natural rubber due to its synthetic nature and manufacturing process. However, the long-term durability and resistance to weathering of EPDM can offset the initial cost in certain applications. Natural rubber is more cost-effective but may require more frequent replacement due to its lower resistance to aging and weathering.

Conclusion

In conclusion, EPDM and natural rubber have their own unique properties that make them suitable for different applications. While EPDM is known for its excellent weather resistance and durability, natural rubber is valued for its high elasticity and resilience. Understanding the differences between these two materials can help in choosing the right material for a specific application based on the requirements and constraints.