polyethylene (PE) is a thermoplastic resin produced by polymerization of ethylene. In industry, it also includes copolymers of ethylene with a small amount of alpha-olefin. Polyethylene odorless, non-toxic, feel like wax, has excellent low temperature resistance (lower use temperature can reach -100~-70°C), good chemical stability, resistance to most acid and alkali erosion (not resistant to acid with oxidation properties). Insoluble in general solvents at room temperature, low water absorption, good electrical insulation.

HDPE barrel material properties

It is a polymer formed by polymerization of ethylene monomer. Polyethylene was synthesized by ICI in 1922, began industrial production in 1939, formal industrial production in the United States, and was an important radar insulation material and military supplies in the war. After the war, Japan's Mitsui Petrochemical and Sumitomo Chemical (1958) began formal production. In 1975, the annual output of the 14-year plant was 1.407 million tons, second only to the United States.

In 1933, the British chemical industry company Bruneman discovered that ethylene can be polymerized to produce polyethylene under high pressure. This method was industrialized in 1939 and is commonly known as the high-pressure method. In 1953, K. Ziegler of the Federal Republic of Germany found that ethylene can be polymerized under low pressure with TiCl4-Al(C2H5)3 as catalyst. This method was put into industrial production by the Federal German Hearst Company in 1955, commonly known as low-pressure polyvinyl polyethylene

In the early 1950s, the United States Philip Oil Company found that with chromium-silicon aluminum oxide rubber as a catalyst, ethylene can be polymerized to produce high-density polyethylene under medium pressure, and industrial production was achieved in 1957. In the 1960s, Canada's DuPont company began to use ethylene and alpha-olefin solution to produce low-density polyethylene. In 1977, the United States Union Carbide Company and Dow Chemical Company successively used low pressure method to produce low density polyethylene, called linear low density polyethylene, of which the gas phase method of Union Carbide company is the most important. Linear low-density polyethylene has similar properties to low-density polyethylene, but also has some characteristics of high-density polyethylene, coupled with low energy consumption in production, so it has developed very rapidly, becoming one of the most striking new synthetic resins.

The core technology of low pressure method lies in catalyst. The TiCl4-Al(C2H5) 3-body polyethylene structural formula system invented by Ziegler in Germany is a substitute catalyst for polyolefin, with low catalytic efficiency and several kilograms of polyethylene per gram of titanium. In 1963, the Belgian Solvay Company pioneered the second generation catalyst with magnesium compounds as the carrier, and the catalytic efficiency reached tens of thousands to hundreds of thousands of grams of polyethylene per gram of titanium. Using the second generation catalyst can also save the post-treatment process of removing catalyst residue. Later, gas phase catalysts were developed. In 1975, the Italian Monte Edison Group company developed a catalyst that can directly produce spherical polyethylene without granulation, known as the third generation catalyst, which is another change in the production of high-density polyethylene.

Polyethylene is a crystalline thermoplastic resin. Their chemical structure, molecular weight, degree of polymerization, and other properties depend heavily on the polymerization method used. The polymerization method determines the type and degree of branch chain. The degree of crystallinity depends on the degree of regularity of the molecular chain of the component and its thermal history.

Polyethylene is very sensitive to environmental stresses (chemical and mechanical effects), and its heat resistance to aging is worse than the chemical structure of the polymer and the processing strip. Polyethylene can be processed by general thermoplastic molding methods (see plastic processing). It is widely used in the manufacture of films, packaging materials, containers, pipes, monofilament, wire and cable, daily necessities, etc., and can be used as high frequency insulation materials for TV, radar, etc. With the development of petrochemical industry, the production of polyethylene has developed rapidly, and the output accounts for about 1/4 of the total output of plastics. In 1983, the world's total polyethylene production capacity was 24.65Mt, and the plant capacity under construction was 3.16Mt. According to the latest statistics in 2011, the global production capacity reached 96Mt, and the development trend of polyethylene production shows that production and consumption have gradually transferred to Asia, and China has increasingly become the most important consumer market.

HDPE drums are used in nuclear physics, astrophysics, and reactor operation to measure the neutron content of polyethylene as a diffuse agent. He has made his own contribution to the research of nuclear physics.

Polyethylene (PE) plastic, we often carry a convenient bag is polyethylene (PE). Polyethylene is the simplest polymer and the most widely used polymer material. It is made up of repeated - CH2 - units connected. Polyethylene is formed by the addition polymerization of ethylene (CH2=CH2).

The properties of polyethylene depend on how it is polymerized. High density polyethylene (HDPE) was synthesized by Ziegler-Natta polymerization under medium pressure (15-30 atmospheres) of organic compounds. The polyethylene molecule polymerized under this condition is linear, and the molecular chain is very long, and the molecular weight is up to hundreds of thousands of thousands. If it is under high pressure (100-300MPa), high temperature (190-210C), peroxide-catalyzed free radical polymerization, the production is low density polyethylene (LDPE), which is branched chain structure.