Generally, the suspension polymerization process is
adopted to manufacture PVC. First, the raw material
VCM is pressurized and liquefied, and then fed into
the polymerization reactor, which contains water and
suspending agent in advance. Through high- speed
agitation within the reactor, micro particles of VCM
are obtained. Next, the initiator for polymerization is
fed into the reactor, and PVC is produced by reaction
under a few atmospheric pressures at 40 - 60
℃
.
PVC obtained through suspension polymerization is
suspended in water as micro particles of 50~200 µm
diameter (in slurry form). Therefore, slurry discharged
from the polymerization reactor is dehydrated, dried
and the particle size matched by screening to yield PVC
in the form of white powder. The unreacted VCM is
entirely recovered through the stripping process, and
after refining, recycled as raw material for reuse in this
process (Fig.1- 6). Emulsion polymerization process and
bulk polymerization process are also adopted.