Exonic Polymers is a leading manufacturer of custom EPDM Rubber products. EPDM is short for the chemical formulation name known as Ethylene propylene diene monomer. EPDM is a synthetic rubber elastomer that exhibits outstanding ozone, weather, and heat resistance and has excellent electrical insulating properties. It is often used for applications that are exposed to outdoor or high heat environments. The molecular structure contains a single bond, which is what provides EPDM these strong characteristics. 

EPDM is one of the most commonly used rubber elastomers in the world and can be manufactured in a variety of different processes including continuous extrusion, molded products, O-rings, and die-cut. These extremely versatile material is used in many applications from automotive to HVAC to building materials & construction.

Molded EPDM P-Rings Extruded EPDM Rubber Die-Cut EPDM Rubber

EPDM Rubber Advantages & Benefits

  • Excellent resistance to UV exposure, ozone, aging, weathering, and many chemicals - great for outdoor applications
  • Stability in high and low temperatures - a general purpose EPDM material can be used in an environment where the temperature range is from -20⁰F to +350⁰F (-29⁰C to 177⁰C).
  • Low electrical conductivity
  • Water resistant
  • Properties allow it to be widely used and highly versatile, can be applied successfully in many situations
  • Used in the proper environment, the parts will work well and last long without breaking down, becoming brittle, etc. - saving you money on replacements
  • Less expensive than silicone, with similar properties (where heat below 250⁰F is present)

EPDM Rubber Properties

Common Name: EPDM

ASTM D-2000 Classification: CA

Chemical Definition: Ethylene Propylene Diene Monomer

Specific Gravity: 0.86

Temperature Range

Low Temperature Usage: -20° to -60° F

High Temperature Usage: Up to 350° F

Tensile Strength

Tensile Range: 500-2500 P.S.I. - Good

Elongation: 600% Maximum - Good

Durometer (Hardness)

Range: 30-90 Shore A

Resilience / Rebound: Good

Abrasion Resistance: Good - Excellent

Tear Resistance: Fair - Good

Compression Set: Good

Additional Properties

Aging Weather: Excellent

Adhesion to Metals: Fair - Good

Solvent Resistance: Poor

Oil Resistance: Poor

Heat Resistance: Good - Excellent

Flame Resistance: Poor

Common EPDM Applications


  • Compressor Grommets
  • Pressure switch tubing
  • Panel gaskets and seals


  • Weather stripping and seals
  • Wire and cable harnesses
  • Window spacers
  • Hydraulic brake systems
  • Door, window and trunk seals
  • Cowl Seals

Recreational Vehicles

  • Weather stripping and seals
  • Slide-out seals
  • Door, window and trunk seals
  • Hatch Seals


  • Water system O-rings and hoses
  • Tubing, grommets, and belts
  • Electrical insulation and stinger cover
  • Tubing & cord
  • Gaskets & Seals
  • Window glazing gaskets
  • Door gaskets

Architecture & Glazing

  • Locking gaskets
  • Weather stripping
  • Curtain wall seals
  • Setting blocks
  • Shims
  • Spacers

Agriculture & Construction

  • Window & door seals
  • tubing & hose