AEM / Vamac®

Ethylene / Acrylic elastomer (AEM, Vamac®)

Ethylene / acrylic elastomer is a copolymer of ethylene and methyl acrylate plus a small amount of a curesite monomer containing carboxylic acid groups. AEM is a tough, low-compression-set rubber with excellent resistance to high temperatures, hot mineral oil, fluids and weathering. The low temperature flexibility and mechanic properties are better than ACM, but it is not well resistant to low aniline oil (like ASTM No. 3 oil) and polar solvents. AEM is typically chosen for applications requiring improved performance versus Nitrile rubber, Neoprene or reduced cost versus higher-end elastomers such as HNBR, FKM. It also usually is applied in automatic industry.

Cure system


Standard AEM compounds are Amine based vulcanization system.

Other Common Variations

  • AEM has good flexibility and good tear resistance, abrasion and compression set, and it usually is used in shaft lip seals especially in automatic transmission fluids.
  • Special VAMAC® compounds can improve oil resistance but will sacrifice some low temperature properties

Vamac® is a registered trademark of DuPont Performance Polymers. 

General Information

ASTM D 1418 Designation
Standard Color(s)
ISO/DIN 1629 Designation
Hardness Range
40-85 Shore A
ASTM D2000 / SAE J 200 Codes
Relative Cost
Medium- High

Service Temperatures

Standard Low Temperature
-30°C / -22°F
Special Compound Low Temperature
-40°C / -40°F
Standard High Temperature
150°C / 302°F
Special Compound High Temperature
175°C / 347°

Performs Well In...

  • Ozone, weather and hot air.
  • automatic transmission fluids (ATF) and Power steering fluids
  • water

Doesn’t Perform Well In...

  • Ketones
  • Fuels
  • Brake fluids