Full definition
Chlorosulfonated polyethylene (CSM), commonly known by the brand name Hypalon, is a synthetic rubber that was originally developed by DuPont. Although the Hypalon trademark is no longer in use, the generic polymer remains available and is recognized for its superior weather resistance, ozone resistance, and chemical resistance. CSM is particularly effective against a wide range of chemicals, including acids, alkalis, and oxidizing agents, making it suitable for applications in harsh environments. Its ability to withstand extreme temperatures, from -30 to +120°C, and its excellent abrasion resistance contribute to its versatility in various industrial applications.\n\nThe material exhibits hardness values ranging from 40 to 90 Shore A, with tensile strength between 10 to 20 MPa and an impressive elongation at break of 200 to 500%. These properties make CSM a valuable choice for applications where flexibility and durability are critical. Additionally, CSM can be produced in bright colors without fading, offering aesthetic advantages for applications such as roofing membranes, where reflective properties can enhance energy efficiency.\n\nDespite its advantages, CSM does have some limitations. It demonstrates poor resistance to aromatic and chlorinated solvents, which may restrict its use in certain environments. Moreover, it has a moderate compression set, which could affect its performance in applications requiring long-term sealing capabilities. Compliance with ASTM D2000 standards, specifically categories BE and CE, ensures that CSM meets industry requirements for quality and performance. With its extensive range of applications—such as roofing membranes with lifespans exceeding 20 years, cable jacketing, chemical tank linings, industrial hoses, inflatable structures, and coated fabrics—CSM remains a relevant choice in scenarios where EPDM is less suitable due to color stability or enhanced chemical resistance needs.