chlorosulfonated polyethylene

chemical compound

Also known as: CSM, hypalon

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June 24, 2026

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Chlorosulfonated polyethylene (CSM) is a synthetic rubber produced by modifying polyethylene. This modification involves reacting polyethylene with chlorine or a combination of chlorine and sulfur dioxide, introducing chlorine or chlorosulfonyl groups into the polymer chains. This process results in a material that is elastic, highly resistant to oxidation and ozone, and possesses some flame resistance due to its chlorine content. CSM is primarily used in applications requiring resistance to heat, oil, and abrasion, such as hoses, belts, seals, and coated fabrics.1

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major industrial polymers
Polyethylene (PE)
…in chlorinated polyethylene (CM) or chlorosulfonated polyethylene (CSM), a virtually noncrystalline and elastic material. In a process similar to vulcanization, cross-linking of the molecules can be effected through the chlorine or chlorosulfonyl groups, making the material into a rubbery solid. Because their main polymer chains are saturated, CM and CSM…
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…in chlorinated polyethylene (CM) or chlorosulfonated polyethylene (CSM), a virtually noncrystalline and elastic material. In a process similar to vulcanization, cross-linking of the molecules can be effected through the chlorine or chlorosulfonyl groups, making the material into a rubbery solid. Because their main polymer chains are saturated, CM and CSM…
Read More