EPS – 98% Air

The discovery of expanded polystyrene (EPS) at the beginning of 50s revolutionized many sectors of the economy. Today, it plays an essential role in the life of a myriad of products.

Manufacturing EPS requires a minimal use of raw materials and conforms to the most stringent health and safety requirements in Europe.

Liquid monostyrene is made from petroleum. It is then converted in a number of production steps into the raw material for EPS: expandable polystyrene.

This comprises small, glass-like spheres, which contain a minute quantity of the blowing agent pentane. The pentane, which is comparable to natural gas, is heated by steam that causes the spheres to expand and become the well-known EPS pearls that are up to 50 times larger than their original volume.

The blowing agent escapes from the pearls and the numerous minute cells in each pearl draw in air. When the feather-light and elastic pearls are heated, once more using steam, and compressed in a mould, they merge into a homogeneous moulded product: EPS packaging. During the contour cutting process, a block moulder first converts the individual EPS pearls into a homogeneous block, after which hot wires in series cut out the desired packaging in a completely automated process.

EPS is used in many industries, eg. building and construction, civil engineering, road improvement and landscaping, packaging solutions, automotive, food industry, horticultural and pharmaceuticals.

In the first stage of its manufacture, the expandable polystyrene beads undergo a steam heat treatment. Under the effect of temperature they dilate till they reach about 50 times their original volume. These expanded beads are then injected under pressure into a mould and are subjected again to a steam treatment until they bond together and make the shape of the mould.

The structure of EPS yields many technical advantages

  • light weight
  • excellent thermal insulation capacity
  • easily controllable protection against the impact of shocks and drops
  • flexibility of moulding
  • good strength/weight ratio: 98% air , 2% material
  • stable in adverse weather conditions neutral for the environment and free of CFC
  • suitable for food packaging
  • insensitive to moisture


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