is applied to vinyl chloride (dispersed in water as a suspension
or an emulsion) in high pressure chambers at temperatures of 50-70°C.
The role of water is to remove and control the heat given off in
the polymerisation process. PVC forms as tiny particles which grow
and when they reach a desired size the reaction is stopped and any
unreacted vinyl chloride is distilled off and re-used. The PVC is
separated off and dried to form a white powder.