Hypalon (CSM) Gaskets and O-Rings
The polyethylene polymer contains additional chlorine and sulfur groups. Chlorine gives the material resistance to flame and mineral oil and also improves the cold flexibility.
Both o-rings and gaskets can be made from Hypalon materials.
Names: Chlorosulfonated Polyethylene, CSM, Hypalon®
Compound Info | |
ASTM D1418 Designation | CSM |
ASTM D2000/SAE J200 Type, Class | CE |
Hardness (Shore A) | 45-95 |
Color | black |
Thermal Properties | |
Min Temp. | -50°F (-45°C) |
Max Temp. | 270°F (132°C) |


Chemical Resistance
Many acids
Many oxidizing media
Silicone oil and grease
Water and water solvents
Ozone, aging and weathering resistance

Limited Compatibility
Low molecular aliphatic hydrocarbons (propane, butane, fuel)
Mineral oil and grease
Limited swelling in aliphatic oils (ASTM oil No.1)
High swelling in naphthene and aromatic base oils ( IRM 902, IRM 903)
Polar solvents (acetone, methyl ether, ketone, ethyl acetate, diethyl ether, dioxane)
Phosphate-ester based fluids

NOT Compatible
Aromatic hydrocarbons (benzene)
Chlorinated hydrocarbons (trichloroethylene)
Disclaimer: These are general guidelines only. All materials should be tested in your application.