- Vamac . . . DuPont Elastomers
ASTM D1418 Designation: AEM
ASTM D2000/SAE J200 Type, Class: EE, EF, EG, EA
Apple Compound Designation: VA
Standard Color: Black
Description: A copolymer of ethylene and methyl acrylate, with a small amount of a third monomer added to provide a cure to active groups in the polymer chain, Vamac exhibits properties similar to those of polyacrylate, but with an extended low temperature limit and better mechanicals.
Key Use(s): Seals for automotive applications, such as automatic transmissions & power steering systems.
Standard Compound: -13° to +338°F (Dry Heat Only)
Hardness (Shore A): 50 to 90.
Features: Ideal for automotive sealing uses, Vamac features excellent heat resistance, outstanding resistance to ozone and sunlight aging, moderate resistance to swelling in oils, and very low permeability to gases.
With a maximum reinforced tensile strength of 2,500 psi, Vamac's mechanical properties of adhesion to metals, tear resistance, flex life, abrasion resistance and compression set resistance are all rated as "good".
Resistance to water, engine coolant mixtures (glycols), dilute acids and alkalis is also good.
Limitations: Vamac is not recommended for exposure to concentrated acids, aromatic hydrocarbons, "gasoline", ketones, brake fluids and phosphate esters.