EPDM Rubber vs. Silicone Rubber: Key Differences, Applications, and Performance Comparison

Last Updated May 20, 2025

EPDM rubber offers excellent resistance to weathering, ozone, and UV rays, making it ideal for outdoor applications, while silicone rubber excels in extreme temperature resistance and flexibility. EPDM is generally more cost-effective and performs well in water and steam environments, whereas silicone provides superior performance in food-grade, medical, and high-temperature sealing solutions. Choosing between EPDM and silicone depends on specific environmental conditions, temperature ranges, and industry requirements for durability and compliance.

Table of Comparison

Property EPDM Rubber Silicone Rubber
Temperature Range -40degC to 150degC -60degC to 230degC
Weather Resistance Excellent resistance to ozone, UV, and weathering Superior resistance to ozone, UV, and extreme weather
Chemical Resistance Good resistance to water, steam, and alkalis Excellent resistance to many chemicals and solvents
Flexibility Good flexibility at low temperatures Outstanding flexibility over a wide temperature range
Electrical Insulation Moderate electrical insulation properties High electrical insulation properties
Price Generally lower cost Higher cost due to superior performance
Applications Automotive seals, roofing membranes, water hoses Medical devices, food processing, high-temp seals

Introduction to EPDM and Silicone Rubber

EPDM rubber, a synthetic elastomer known for exceptional weather, ozone, and UV resistance, excels in automotive and roofing applications due to its durability and water resistance. Silicone rubber, a high-performance elastomer, offers superior thermal stability and flexibility in extreme temperatures, making it ideal for medical, food-grade, and electrical insulation uses. Both materials differ fundamentally in chemical structure, with EPDM based on ethylene-propylene-diene monomers and silicone composed of silicon-oxygen chains, influencing their specific properties and suitability across industries.

Chemical Composition Differences

EPDM rubber is a synthetic elastomer primarily composed of ethylene, propylene, and a diene comonomer, which provides excellent resistance to heat, ozone, and weathering. Silicone rubber, in contrast, consists of a silicon-oxygen backbone with organic side groups, granting superior flexibility, thermal stability, and resistance to extreme temperatures. The fundamental chemical composition difference lies in EPDM's carbon-based polymer chain versus silicone rubber's inorganic silicon-oxygen structure, influencing their distinct physical and chemical properties.

Physical Properties Comparison

EPDM rubber exhibits superior resistance to heat, ozone, and weathering, making it ideal for outdoor applications, while silicone rubber excels in temperature tolerance, withstanding extreme cold and heat ranging from -60degC to 230degC. EPDM has excellent elasticity and tensile strength, but silicone offers greater flexibility and biocompatibility with lower compression set. The density of EPDM typically ranges from 0.86 to 0.89 g/cm3, whereas silicone rubber is slightly less dense, averaging around 1.10 to 1.30 g/cm3, influencing weight-sensitive applications.

Temperature Resistance: EPDM vs Silicone

EPDM rubber withstands temperatures ranging from -40degC to 150degC, making it suitable for moderate temperature applications. Silicone rubber excels with a broader temperature range of -60degC to 230degC, offering superior resistance in extreme heat and cold environments. This makes silicone the preferred choice for high-temperature sealing and insulation needs.

Weather and UV Resistance

EPDM rubber excels in weather and UV resistance due to its exceptional ability to withstand ozone, sunlight, and extreme temperatures without degrading. Silicone rubber also offers excellent UV stability but outperforms EPDM in maintaining flexibility across a broader temperature range, especially in extreme cold. Both materials are widely used in outdoor applications, but silicone rubber's superior UV and temperature resistance makes it ideal for harsher environments.

Applications in Industry

EPDM rubber excels in automotive weatherstripping, roofing membranes, and electrical insulation due to its outstanding resistance to UV rays, ozone, and heat. Silicone rubber is preferred in medical devices, food processing seals, and high-temperature gaskets because of its superior thermal stability and biocompatibility. Both materials offer unique chemical and physical properties that drive their specific industrial applications, with EPDM dominating outdoor exposure environments and silicone favored for extreme temperature and hygiene-critical uses.

Cost Effectiveness and Availability

EPDM rubber offers superior cost effectiveness compared to silicone rubber, with raw material prices significantly lower, making it ideal for large-scale manufacturing. Its widespread availability in various grades and suppliers ensures consistent supply and reduced lead times. Silicone rubber, while offering excellent temperature resistance and flexibility, often incurs higher costs and limited availability, affecting budget-sensitive projects.

Durability and Longevity

EPDM rubber exhibits exceptional resistance to weathering, ozone, and UV exposure, making it highly durable for outdoor applications and capable of lasting over 20 years under harsh environmental conditions. Silicone rubber offers superior heat resistance and excellent flexibility at extreme temperatures, with longevity often exceeding 30 years in both indoor and outdoor settings. While EPDM is preferred for outdoor sealing and roofing due to its resilience to environmental factors, silicone rubber is favored in high-temperature and medical applications where long-term elasticity and non-reactivity are critical.

Limitations and Drawbacks

EPDM rubber exhibits limited resistance to oils, fuels, and hydrocarbon-based solvents, restricting its use in automotive and industrial applications where exposure to these substances is common. Silicone rubber faces drawbacks such as lower tensile strength and poor abrasion resistance compared to EPDM, making it less suitable for mechanical parts subjected to heavy wear. Both materials have temperature limitations, with EPDM performing poorly at extreme cold and silicone exhibiting reduced mechanical strength at high temperatures.

Choosing the Right Rubber for Your Needs

EPDM rubber offers excellent resistance to weathering, ozone, and UV exposure, making it ideal for outdoor applications and automotive seals. Silicone rubber excels in high-temperature stability and flexibility, suitable for medical devices and food-grade seals where heat resistance and non-toxicity are essential. Assess your specific environmental conditions, temperature range, and chemical exposure to determine whether EPDM or silicone rubber best meets your performance and durability requirements.

EPDM Rubber vs Silicone Rubber Infographic

EPDM Rubber vs. Silicone Rubber: Key Differences, Applications, and Performance Comparison


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The information provided in this document is for general informational purposes only and is not guaranteed to be complete. While we strive to ensure the accuracy of the content, we cannot guarantee that the details mentioned are up-to-date or applicable to all scenarios. Topics about EPDM Rubber vs Silicone Rubber are subject to change from time to time.

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