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Polyethylene.

Polyethylene.

  • Polyethylene(or polythene) is made from the polymerisation of ethylene (or ethene) monomer in the presence of catalyst.
    Polythene
    Polyethylene.
  • It is a polymer of ethylene.
  • Polyethylene is resistant to water,acids, alkalies and most solvents.
  • Polyethylene contains the chemical elements carbon and hydrogen.
  • Polyethylene (PE) is a plastic.
  • Polyethylene belongs to the family of plastics called thermoplastics.

Types of polyethylene.

Based on density, polyethylene is classified into two types.
Low density polyethylene.
High density polyethylene.

Low density polyethylene.

  • Low density polyethylene (LDPE) has a density range of 0.910 - 0.940 g/cm³ and is prepared by the free radical polymerisation of ethene.
  • It is a poor conductor of electricity and is chemically inert.
  • The LDPE is used for making plastic bags and film wrap.

High density polyethylene.

  • High density polyethylene (HDPE) has a density range of 0.93 - 0.97 g/cm³.
  • It is obtained when addition polymerisation of ethene take place in a hydrocarbon solvent.
  • They are chemically inert as well as are used in making bottles, milk jugs, pipes and garbage containers. Next

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