Commonly used materials for hollow sheet products, polyethylene (PE)


Polyethylene, a commonly used material in hollow sheet products, is a crystalline or semi-crystalline saturated hydrocarbon formed by ethylene addition polymerization.
There are many types of polyethylene, and there are many classification methods, such as the method of polymer synthesis, polymer molecular chain structure, polymer density and the like. In addition, in the same type of polyethylene, it can be divided into homopolymers and copolymers according to the number of synthetic monomers.
Classified according to the method of polymer synthesis, this classification method began in the early stage of industrial production of polyethylene, and it has been used until now. As polyethylene is classified according to the density of the polymer, the density of polyethylene is in the range of about 0.860 - 0.965 g/cm3. Within this range, according to the density of polyethylene, it is divided into various types of polyethylene, which is a customary classification method on the market. They are ultra low density polyethylene (ULDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), high relative molecular mass. Density polyethylene super high molecular weight denier high density polyethylene (UHMWHDPE) and so on.
Basic properties of polyethylene and its films The chemical composition of polyethylene is relatively simple. However, although the chemical composition is the same, different polymerization conditions form different molecular structures (such as linear and branched), thereby producing different types of polyethylene such as low density polyethylene, linear low density polyethylene, and high density polyethylene. . Since the chemical structure of polyethylene is relatively simple, it is easy to enter the crystal lattice, resulting in higher crystallinity. However, the branching of the chain interferes with its crystallization ability, which lowers its relative molecular mass, thereby reducing the density of polyethylene.
The hollow sheet raw material polyethylene is almost insoluble in organic solvents at normal temperature, but it will grow in contact with aliphatic hydrocarbons, aromatic hydrocarbons and halogenated hydrocarbons for a long time; it will produce permanent contact with oils (mineral oil, vegetable oil, animal fat). Sexual deformation. When the temperature exceeds 70 ° C, it can be dissolved in a small amount in a solvent such as toluene, acetic acid, valeric acid, trichloroethylene, turpentine, mineral oil or paraffin.

  • 11/03/2019
  • Recently
Click here to view Previous or Next

Related News

Cost-effective industrial laminate

Cost-effective industrial laminate

  • 13/02/2019 09:10:01

The cheapest industrial laminates (Class X) are used in large quantities where the dielectric properties are less important. It is made from unbleached kraft paper and about 30% phenolic resin. It has …

Read more

Casting PA film and production technology

Casting PA film and production technology

  • 21/12/2017 09:33:12

Casting PA film and production technology 1. Casting PA film and its raw materials used: PA film has the advantages of high strength, good toughness, good transparency, good heat resistance and cold…

Read more

Cast film mechanical winding device

Cast film mechanical winding device

  • 19/12/2017 09:21:48

Cast film mechanical winding device Corona treatment device: cast film after corona treatment, can improve the surface tension of the film to improve the printing of the film and together with other…

Read more

Downstream production line auxiliaries

Downstream production line auxiliaries

  • 18/12/2017 09:42:18

Downstream production line auxiliaries Thickness measurement device: In the high-speed continuous production process, cast film thickness measurement must be non-contact automatic tracking. Most o…

Read more

Hot News

Calendered film and hard sheet

Calendered film and hard sheet

Calendered film and hard sheetCalendering is a method in which a thermoplastic film of two or more phases is compression molded between rotating rolls to produce a continuous film or sheet.In the field of plastic processing, the extrusion method is the ma

Extrusion theory and characteristics of extrusion

Extrusion theory and characteristics of extrusion

The flow theory of plastics in the extrusion process: The modern ordinary extrusion theory is based on the three basic functions of solid transportation, melting and melt transportation. Thus, a conventional screw includes three functional segments: a sol

Thermoforming of plastics

Thermoforming of plastics

Thermoforming of plasticsThermoforming is a method of making plastic articles using sheets of thermoplastics as a raw material. When manufacturing, the sheet cut into a certain size and a fixed shape is first clamped on the frame and heated to a thermoela

The general principle of blow molding

The general principle of blow molding

The general principle of blow molding can be summarized as the blowing of compressed air into a molten parison, which is laterally inflated, pressed against the sub-mold type control surface, and cooled to form a hollow product. Therefore, blow molding ge

Processability of LLDPE and its films

Processability of LLDPE and its films

The amount of LLDPE used has accounted for 30% of the total amount of three major types of polyethylene, of which about 80% is used to produce various films. Although LLDPE is easy to form various films, it has a relatively narrow range of relative molecu

Tags