About EPS

What is EPS?

Expandable Polystyrene (EPS) is a polymer with a number of unique properties.

EPS consists of 98% air, has an excellent insulation value, is light yet rigid. Unlike other insulation materials, EPS also has minimal water absorption.

♻️ 100% Recyclable

Additionally, EPS allows for easy and safe processing, is sustainable and 100% recyclable. In this way, EPS makes an excellent contribution to further reducing CO₂ emissions.

Areas of application

The unique properties referred to above have over several decades made EPS a highly successful raw material that can be used in a broad range of products and applications. Examples include applications in the building and construction industry, packaging industry, agriculture and civil engineering sectors.

How is EPS made?

The EPS beads are produced by Unipol by means of a suspension polymerisation process.

Styrene, together with pentane, water and other chemicals, is converted by a mixer reactor into small EPS (Expandable Polystyrene) beads. These beads are then dried, sieved and finally coated.


The producers of expanded polystyrene products use steam to heat the EPS beads. This releases the pentane and causes the EPS beads to expand into loose foamed EPS beads that are up to 50 times their original volume. The excellent insulation value of EPS lies in the fact that all foamed EPS beads have a fine closed cell structure in which air is trapped, up to 98% of its total volume.

Final forming

In this phase, the loose foamed EPS beads are reheated with steam in a mould to form a homogenous EPS end product.

Watch video ‘How it’s made’

Watch an episode of Discovery Channels ‘How it’s made’ in which the production process of EPS is explained.

Watch video

airpop®, the new name for EPS

Expanded Polystyrene is an established material in Europe and goes under many names in the countries where it is used. The EPS industry is now introducing a uniform European name for EPS: airpop® engineered air.

Why give a new name to an internationally established material such as EPS? Simply because the name airpop® so accurately expresses what material is made of: air. Lots of air. 98% air, to be precise. Only a small percentage consists of a polymeric material that has been expanded to 50 times its original volume.

airpop® protects what has to be protected: the heads of your children, TV appliances, fresh fish and thousands of other products. airpop® offers easy and affordable building and insulation applications thanks to low material costs, low weight, low CO2 emissions and low heating costs.

The airpop® campaign is a joint initiative of EUMEPS (the European producers of EPS), European airpop® processors, their national EPS associations and the European EPS producers of raw materials.

Visit EUMEPS website