Bouling Chemical Co., Limited

What Is EPS?

Expanded polystyrene EPS is a closed cell, lightweight, resilient, foamed plastic providing a host of unique properties.
Expandable polystyrene is produced in a wide range of densities providing a varying range of physical properties. These are matched to the various applications where the material is used to optimise its performance and strength.

How EPS Is Made?

The production of EPS products requires that the raw materials be pre-conditioned prior to their final "tooled" moulding process.
The raw material (also known as "expandable polystyrene" or "bead") has a sperical shape and is similar to sugar in appearance.
Pre-expansion:
The tiny spherical polystyrene beads are expanded to about 40 times their original size using a small quantity of pentane (typically 5% by weight) as a blowing agent. This process involves the heating of beads, using a flow of steam, which causes the blowing agent to boil and thus a honeycomb of closed cells is formed.
Maturing:
As the material cools the pentane liquefies and a partial vacuum is formed inside the bead. The beads are returned to a holding tank for approximately twelve hours to allow the pressure differential to equalize, giving a stabilised granule.
Final Forming:
In this final stage the pre-expanded stabilized beads are reheated with steam in a mould. The final expansion takes place and the beads coalesce to give a shaped moulding. This can also be used to form large blocks which can be sectioned to the required shape as panels, boards, cylinders etc. In this final form the EPS is made up of 98% air.