Tips on Chlorinated Paraffin Plasticizers

Developed in the early 1930s, chlorinated paraffin (CP) is an artificial complex mixture of polychlorinated n-alkanes. The chlorination of CPs can vary between 30 percent and 70 percent. CPs are generally subdivided according to their carbon chain length into short-, medium- and long-chain CPs. They are normally liquid and are virtually insoluble in water. Solid CPs are made from longer chain paraffins and are typically 70 percent to 72 percent chlorinated.

Manufacture

• Four main types of CPs are manufactured, and each type is determined by the length of its carbon chain. Most liquid CPs are made from n-paraffins with chain lengths as follows: short (10 to 13 carbon molecules), medium (14 to 17 carbon molecules) and long (18 to 20 carbon molecules). Generally, solid CPs and waxes are made with chain lengths averaging about 25 carbon molecules.

Uses of Paraffin Plasticizers

• Today, more than 200 chlorinated paraffin formulations are used in a wide range of industrial applications including flame-retardants and plasticizers as well as additives to metal working fluids, sealants, paints, adhesives and coatings. CPs are used as plasticizers in various products, and they add flexibility to polyvinyl chloride (PVC) in pipes and fittings, plastic flooring and cable sheathing.

Benefits

• A major benefit of using chlorinated paraffin is fire resistance. CPs are often used instead of phosphate or bromine-based fire retardants. Most CPs are unlikely to vaporize and are considered chemically inert (inactive).

Environmental Impact and Disposal

• CP does not appear to be obstructive to the food chain, unlike compounds like polychlorinated biphenyls (PCBs). CPs may pose a risk because of their widespread use. CPs stability and slow breakdown imply a high potential for bioaccumulation and should be recovered from waste and recycled when possible.