And in the third process, the PVC Process, VCM is polymerized to produce polyvinyl chloride (PVC) resin in batch reactors. After polymerization, VCM is stripped from the resin and the resin is finaly dried to produce high quality PVC resin which fulfills the international health and hygiene standards and technically satisfies highly demanding applications.

The majority of PVC resin production nowadays is using suspension polymerization method. In a typical suspension polymerization, a known quantity of demineralized water is charged into a pressure vessel and other polymerization ingredients such as initiator, buffer and protective colloid are added. The vessel is then sealed and evacuated and vinyl chloride (VCM) is introduced into the vessel. Protective colloid action and agitation on the reaction mixture promote the formation of micro-droplets of VCM in water.

At the end of polymerization reaction, PVC slurry (PVC resin particles in water) is discharged out of the reaction vessel and the remaining unreacted VCM is stripped from the PVC slurry in a highly effective stripping column. The slurry is then centrifuged to separate most of the water, resulting in PVC resin which still contains small amount of water, which is then introduced into the dryer to give dry PVC resin ready to be delivered to customers.