3. Other types of PVC stabilization

Like other polymers, PVC needs to be stabilized to meet certain performance requirements in the final application. Stabilization occurs when the additive acts on the chemical structure of the polymer or its decomposition products, as opposed to other types which modify physical properties, such as impact modifiers. Other types of stabilization may, for example, be :

• fire resistance (although PVC is already a naturally flame-retardant polymer);

• resistance to weathering ;

• resistance to ozone attack.

Unlike thermal stabilization, there are no other PVC-specific stabilizers to address these different degradation modes. UV stabilizers, for example, whether organic or inorganic, are the same as those used in large quantities in polypropylene or...