Chlorinated polyethylene (PE-C) is an inexpensive variation of polyethylene having a chlorine content from 34 to 44%. It is used in blends with polyvinyl chloride (PVC) because the soft, rubbery chlorinated polyethylene is embedded in the PVC matrix, thereby increasing the impact resistance. In addition, it also increases the weather resistance. Furthermore, it is used for softening PVC foils, without risking plasticizer migration. Chlorinated polyethylene can be crosslinked peroxidically to form an elastomer which is used in cable and rubber industry. When chlorinated polyethylene is added to other polyolefins, it reduces the flammability.
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Chlorinated polyethylene Wikipedia(Text) CC BY-SA