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Low-density polyethylene LDPE is a synthetic resin using a （ ）
high pressure process via free radical polymerization of ethylene
and is therefore also called “high-pressure polyethylene”. Since
its molecular chain has many long and short branches, LDPE is
less crystalline than high-density polyethylene (HDPE) and its
density is lower. It features light, exible, good freezing resistance
and impact resistance. LDPE is chemically stable. It has good
resistance to acids (except strongly oxidizing acids), alkali, salt,
excellent electrical insulation properties. Its vapor penetration rate
is low. LDPE has high uidity and good processability. It is suitable
for being used in all types of thermoplastic processing processes,
such as injection molding, extrusion molding, blow molding,
rotomolding, coating, foaming, thermoforming, hot-jet welding and
thermal welding.
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LDPE is principally used for making films. It is widely used in
the production of agricultural film (mulching film and shed film),
packaging lm (for use in packing candies, vegetables and frozen
food), blown lm for packaging liquid (for use in packaging milk,
soy sauce, juice, bean curds and soy milk), heavy-duty packaging
bags, shrinkage packaging film, elastic film, lining film, building-
use film, general-purpose industrial packaging film and food
bags. LDPE is also widely used in the production of wire & cable
insulation sheath. Cross-linked LDPE is the main material used in
the insulation layer of high-voltage cables. LDPE is also used in the
production of injection-molded products (such as arti cial owers, fi fl
medical instruments, medicine and food packaging material) and
extrusion-molded tubes, plates, wire & cable coatings and pro led
plastic products. LDPE is also used for making blow-molded hollow
Applications
