PRC refers to People's Republic of China (PRC).
Low density polyethylene (LDPE) usually uses ethylene as monomer, and it is prepared in 98. 0 ~ 294 MPa, using
The density of the polymer obtained by polymerization with oxygen or organic peroxide as initiator is 0. 9 10 ~ 0.9259/cm3。
The density of medium density polyethylene (MDPE) is 0.926 ~ 0.9409/cm3；; Very low density polyethylene (VLDPE)
The density is lower than 0.9 10g/cm3.
There are long and short chains in the molecular chain of low density polyethylene. The crystallinity is low, and the molecular weight is generally between 500,000 and 500,000. it is
A waxy solid resin, milky white and translucent, non-toxic. The softening point is low, and it melts when it exceeds the softening point.
Good hot weldability, good formability, good flexibility, good impact toughness and low temperature resistance, and can be used for
The working temperature is -60℃ ~-80℃, and it has good electrical insulation (especially high frequency insulation) and high mechanical strength.
Poor heat resistance, environmental stress cracking resistance, poor adhesion, adhesiveness and printability, and need to pass through the surface.
Mechanisms such as chemical erosion, corona and other treatments can improve its adhesion and printability. The water absorption rate is very low, almost none.
Water absorption and excellent chemical stability, such as stability to acid, alkali, salt and organic solvent. For CO2, organic odor
Gas has high permeability, but poor permeability to water vapor and air. Flammable, burning like paraffin; During the day
Moreover, under the action of heat, it is easy to age and degrade, change color, turn from white to yellow to brown, and finally turn black, and its performance is degraded or turtle.
Cracking, if a certain amount of antioxidants, ultraviolet absorbers, etc. are added. Can improve the performance, under the chemical crosslinking agent or high-energy radiation
Crosslinking can improve softening point, temperature resistance, stiffness and solvent resistance.
Low density polyethylene (LDPE) is suitable for various molding processes of thermoplastic molding, and has good processability.
Such as injection molding, extrusion molding, blow molding, rotational moulding, coating, foaming process, thermoforming, hot air welding, hot welding, etc.
LDPE is mainly used as film products, such as agricultural film, ground covering film, agricultural film and vegetables.
Shed film, etc. Packaging film such as candy, vegetables, frozen food packaging; Blown film for liquid packaging (milk,
Soy sauce, juice Tofu, soybean milk); Heavy packaging bag, shrink packaging film, elastic film, lining film; build
Building film, general industrial packaging film and food bag.
LDPE is also used for injection molding products, such as small containers, lids, household goods, plastic flowers, injection-stretching-blow molding.
Plastic container. Medical devices, pharmaceutical and food packaging materials, extruded pipes and plates, wire and cable coatings, different
Profiles, thermoforming and other products; Blow-molding hollow products, such as food containers, including dairy products and jams, medicines,
Containers and cans of cosmetics and chemical products.