PVC is formed by the polymerization of VCM and corresponds to the general chemical formula of (-CH2 -CHCL-)n.
VCM is polymerized in large scale batch reactors in the presence of water, initiators (catalysts) and other additives. The suspended droplets of liquid monomer are progressively converted to solid or porous PVC particles, depending on grade. Unreacted VCM is stripped from the polymer, and water is separated by centrifuging. The polymer is then dried, typically in fluidized bed drying equipment.

Suspension PVC is used for virtually all extrusion, injection moulding and film making processes. Individual grades are characterized by their melt flow properties and their suitability for rigid (unplasticised) or flexible (plasticised) applications.

The E-PVC Process

Emulsion PVC is used in a wide range of specialty applications, involving coating, dipping or spreading, for which S-PVC cannot be used.
The polymerization stage involves an emulsion of very fine droplets of VCM in water, and the process forms a stable emulsion, or latex, of polymer in water. After the removal of unreacted monomer, the water is removed by evaporation in spray drying equipment.