Chemistry Reference
In-Depth Information
ETHYLENE DERIVATIVES
Water
CH
3
CH
2
OH (ethanol)
O
Oxygen
water
CH
2
CH
2
(ethylene oxide)
HOCH
2
CH
2
OH (ethylene glycol)
Oxygen
CH
3
CHO (acetaldehyde)
CH
3
COOH (acetic acid)
Chlorine
vinyl chloride
CH =
2
CH
2
(ethylene)
=
CH
2
CHCl (vinyl chloride)
(CH
2
CHCl)
x
(polyvinyl chloride)
Acetic acid
=
CH
3
COOCH
2
CH
2
(vinyl acetate)
Benzene
catalyst
CH
=
CH
2
(styrene)
CH
2
CH
3
(ethylbenzene)
Ethylene
(CH
2
CH
2
)
x
(polyethylene)
About 50% of all the ethylene produced is used to make polyethylene. There
are two main types: “high density” or HDPE and “low density” or LDPE.
HDPE melts higher and is stiffer and harder than LDPE. It is also opaque,
while LDPE is flexible and transparent. HDPE is used for molding bottles,
housewares, toys, and for extruding pipe and conduit. LDPE is used mainly
for packaging film. HDPE is made by a
at relatively
low pressure while LDPE is made by polymerization at very high pressure
using a different catalyst.
Vinyl acetate is polymerized to poly(vinyl acetate), (PVAc), which finds
use in adhesives and water-based paints. Some PVAc is
catalytic polymerization
(reacted
with water) to poly(vinyl alcohol) (PVA) for textile sizing, adhesives, and
paper coatings. A substantial amount of U.S.-produced vinyl acetate is
exported. Prior to 1970, almost all vinyl acetate was made from acetylene.
Now none of it is.
hydrolyzed
