(CH2-CHCl-CH2-CH2)n
What is Chlorinated Polyethylene?
Chlorinated Polyethylene is a family of thermoplastics that are produced by the chlorination of high-density polyethylene.
Chlorine content can be as high as 70% by weight but most grades have chlorine content in the 25% up to 42% range.
Properties
CPE offer a range of properties and have inherent resistance to heat, oxidation, and ozone due to their saturated molecular backbone, which is further enhanced by molecular modification with chlorine.
Advantages
• Good anti-ageing property and excellent weatherability.
• Good anti-combustion, no self-ignition
• Good low-temperature flexibility. Used in UPVC products
• Good endurance to chemicals.
• Good processing ability. It’s easy to be shaped
• Good stability
What is it used for?
Although it can be used by itself as special synthetic rubber, CPE is a versatile product that is compounded with other materials to achieve different properties and products. It is widely used as a thermoplastic elastomer (TPE), rubber and modifier for resins (PVC, PE and ABS)
Its main use is as an impact modifier that improves the impact resistance and lowers the cost of rigid and otherwise brittle (unplasticised) PVC. Building products include rainwater goods, below ground drainage, profiles, doors and windows.
CPE and the Environment
Known emissions resulting from combustion include carbon monoxide, carbon dioxide and hydrogen chloride.
‘At temperatures exceeding melt temperatures, polymer fragments can be released. Fumes can be irritating. Decomposition products can include and are not limited to: aldehydes, alcohols, organic acids, hydrogen chloride. Decomposition products can include trace amounts of: Hydrocarbons.’ (DOW Material Safety Data Sheet for Chlorinated Polyethylene Resin)