Chemistry Reference
In-Depth Information
ETHYLENE DERIVATIVES
V
C
INYL
HLORIDE
=
+
+
=
+
CH
CH
Cl
O
CH
CH-Cl
H
O
2
2
2
2
2
2
Older Method of Preparation
=
+
=
+
CH
CH
Cl
Cl-CH
-CH
-Cl
CH
CH-Cl
HCl
2
2
2
2
2
2
ethylene dichloride
Uses
Vinyl chloride is used exclusively for the preparation of plastics,
by homopolymerization to poly(vinyl chloride) (PVC) and by
copolymerization with other vinyl (-CH
CH-) compounds.
PVC-type polymers are low-cost, fire retardant, and have good
structural properties.
=
2
Suppliers
OxyVinyls, Dow, Georgia Gulf, Formosa Plastics, Westlake.
About 10% of the ethylene produced in the U.S. is used to make vinyl
chloride, which in the chemical trade is usually referred to as “vinyl chloride
monomer” or VCM. The largest use of VCM is for polymerization to
poly(vinyl chloride) (PVC), a thermoplastic, which in terms of volume is
second only to polyethylene. PVC is used in such diverse areas as containers,
floor coverings (linoleum), plastic pipes, raincoats, and many, many others.
PVC has an evironmental disadvantage over non-chlorine containing plastics
in that when it is disposed of by incineration it produces hydrogen chloride,
which dissolves in atmospheric water to give hydrochloric acid. Polyethylene
does not have this undesirable feature.
VCM is very toxic and is a known cause of a rare form of liver cancer.
However, products made from it, such as PVC, pose no health threats.
