Buna is designed to have a resistance to oil, hydrocarbons, and chemicals. It is readily used in the brewing world, as well as in the crude oil and petrochemical industries. Buna has a temperature rating of -40 to +212 Fahrenheit.
EPDM is designed to have a resistance to ozone, sunlight, oxygen, acids, alkalis, ketones and aging. EPDM has a temperature rating of -40 to +225 Fahrenheit.
Viton is designed to handle strong acids, petroleum products, solvents, and oils. It is not recommended for use with hydrocarbons, ketones, and steam. Viton has a temperature rating of +5 to +400 Fahrenheit.