Chlorinated paraffins (CPs) are complex mixtures of polychlorinated n-alkanes. The chlorination degree of CPs can vary between 30 and 70 wt%. CPs are subdivided according to their carbon chain length into short chain CPs (SCCPs, C 10–13 ), medium chain CPs (MCCPs, C 14–17 ) and long chain CPs (LCCPs, C17 ). Depending on chain length and chlorine content, CPs are colorless or yellowish liquids or solids.
Chlorinated paraffins are synthesized by reaction of chlorine gas with unbranched paraffin fractions (2% isoparaffins,100 ppm aromatics) at a temperature of 80 - 100 °C. The radical substitution may be promoted by UV-light.
Production of CPs for industrial use started in the 1930s. Currently, over 200 CP formulations are in use for a wide range of industrial applications, such as flame retardants and plasticisers, as additives in metal working fluids, in sealants, paints, adhesives, textiles, leather fat and coatings.