HDPE

Polyethylene production

High-density polyethylene can be produces using one of two methods.

The low-pressure method requires using a pressure within the 1 to 50 bar range and a temperature between 20 and 150°C.

The medium-pressure method, the reaction conditions are pressure between 30 and 40 bar, and temperature within the 85-180°C range.

Polyethylene structure and properties

HDPE is made up of a linear chain with a low number of branches and co-monomers, such as butane or hexane. The non-branching structure is achieved by applying appropriate catalysts during the production process, and by maintaining the right conditions of the polymerisation reaction. Such a structure of the polyethylene chains results in high intermolecular forces, which makes polyethylene resistant to stretching.

High-density polyethylene is characterised by a high resistance to water and solutions of acids, bases, salts, alcohols, and gasoline. However, it is not as resistant to the effects of strong oxidising acids, such as sulfuric and nitric acids, or to strong detergents. HDPE is odourless and physiologically neutral, which makes it attractive for numerous applications.

Polyethylene applications

High-density polyethylene is used in many industries. It is utilised especially in such applications where high tensile strength, low moisture absorption, high impact strength and good anti-corrosion properties are required. HDPE can be manufactured by extrusion, blowing extrusion, injection, and rotary moulding. It can also be treated and joined by welding. These qualities enable obtaining elements greatly varying in shapes and dimensions, characterised by high durability and strength.

HDPE finds use in the manufacturing of industrial packaging materials, bottles, medical products, containers, jerry cans, films, tapes, fibres, toys, pipes, fuel tanks, and many others. Due to the extremely broad range of polyethylene applications, it is used virtually in every industry in existence.