New Chlorosulfonated Polyethylene (CSM) Manufactured without the Use of Organic Solvents

Chlorosulfonated Polyethylene (CSM) is an oil, heat, flame, and weather resistant elastomer which has found many applications in industry including wire & cable jackets, hydraulic hose, roll covers and roofing membranes.  CSM has historically been commercially produced through the chlorination and chlorosulfonation of polyethylene in a solution process.  The process of chlorination reduces the crystallinity of the polyethylene chain, while the introduction of sulfonyl chloride groups provides sites that are readily cross-linkable with non-peroxide curatives.

One of the disadvantages of the solution based manufacturing processes is that it requires the use organic solvents such as carbon tetrachloride.  Typically residue from these solvents is only present in the final products at minimal levels and does not present undue hazard to personnel; however their suspected carcinogenetic and environmental effects make the manufacturing process more complex and costly due to stringent safety and environmental requirements on handling and storage.  In addition the use of some of these solvents is gradually being phased out due to international regulation and the need to move to more “environmentally friendly” technologies.

This paper demonstrates that a suitable alternative technology is available which can be used for the manufacture of Chlorosulfonated Polyethylene which does not require the use of organic solvents.  The subsequent materials are suitable as replacements for solution based CSM in a wide range of applications and are a more environmentally friendly alternative to the existing commercialized technology.