NO. Polyethylene is very sensitive to environmental stress (chemical and mechanical effects), and its heat aging resistance is worse than the chemical structure and processing of polymers. Polyethylene can be processed by general thermoplastic molding methods. It has a wide range of uses, mainly used to make films, packaging materials, containers, pipes, monofilaments, wires and cables, daily necessities, etc., and can be used as high-frequency insulating materials for TVs and radars. With the development of petrochemical industry, Mechanical Ceramic Parts polyethylene production has developed rapidly, and the output accounts for about 1/4 of the total output of plastics. In 1983, the total production capacity of polyethylene in the world was 24.65 Mt, and the capacity of installations under construction was 3.16 Mt. According to the latest statistics in 2011, the global production capacity reached 96 Mt. The development trend of polyethylene production shows that production and consumption are gradually shifting to Asia, and China is becoming the most important consumer market. Polyethylene is classified into high-density polyethylene (HDPE), low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE) according to the polymerization method, molecular weight, and chain structure.
LDPEProperties: tasteless, odorless, non-toxic, matt surface, milky white waxy particles, density about 0.920 g/cm3, melting point 130℃~145℃. Insoluble in water, slightly soluble in hydrocarbons, etc. It can withstand the erosion of most acids and alkalis, has low water absorption, maintains flexibility at low temperatures, and has high electrical insulation.
Production process: There are two main types: high pressure tube method and kettle method. In order to reduce the reaction temperature and pressure, the tubular process generally uses low-temperature and high-activity primers to initiate the polymerization system, with high-purity ethylene as the main raw Mechanical Ceramic Parts material, propylene, propane, etc. as density regulators, and high-activity initiators at about 200℃~ The polymerization reaction is carried out at 330°C and 150-300MPa. The molten polymer that initiates polymerization in the reactor must be cooled and separated by high pressure, medium pressure and low pressure. The high pressure circulating gas is cooled and separated and then sent to the inlet of the ultra-high pressure (300 MPa) compressor. The medium pressure circulating gas is cooled and separated. After separation, it is sent to the inlet of the high-pressure (30 MPa) compressor, and the low-pressure circulating gas is cooled and separated and then sent to the low-pressure (0.5 MPa) compressor for recycling. The molten polyethylene is sent to the pelletizer after high-pressure and low-pressure separation. During the granulation process, the company can add suitable additives according to different application fields, and the granules are packaged and shipped.
Uses: Injection molding, extrusion molding, blow molding and other processing methods can be used. Mainly used as agricultural film, industrial packaging film, pharmaceutical and food packaging film, machinery parts, daily necessities, building materials, wire, cable insulation, coating, synthetic paper, etc.