Chlorinated polyethylene (CPE) is a chlorine-containing thermoplastic elastomer produced through the controlled chlorination of Polyethylene (PE), typically manufactured by aqueous suspension chlorination and obtained as a fine white powder. The incorporation of Chlorine atoms along the polyethylene molecular backbone modifies chain regularity, reduces crystallinity, and alters intermolecular interactions, generating a combination of elastomeric flexibility and thermoplastic processing characteristics. Its physical and mechanical properties are governed by Chlorine content, molecular weight, residual crystallinity, chlorine distribution, and polymer morphology.

In Polyvinyl chloride (PVC) formulations, appropriately selected CPE grades function as impact modifiers by forming dispersed elastomeric domains within the rigid polymer matrix. Under mechanical stress, these domains facilitate localized energy dissipation through deformation mechanisms, reducing brittle fracture and improving impact toughness. CPE also contributes to flexibility, low-temperature impact performance, and durability in suitable formulations. Its effectiveness depends on particle dispersion, interfacial compatibility, modifier concentration, processing conditions, and the resulting phase morphology, particularly in rigid PVC pipes, profiles, fittings, and other impact-resistant applications.