i. Pre-expansion: The tiny spherical beads are expanded to about 40 times their original size using 5% pentane as a blowing agent. The beads are heated by a flow of steam causing the blowing agent to boil and so form the honeycomb of closed cells.
ii. Maturing: When the steam ceases, the recently expanded particles form an internal semi-vacuum which must be compensated for by air diffusion. The pre-foamed material is left to stand for around 12 hours.
iii. Final forming: The stabilised pre-expanded beads are again subjected to steam so that they bind together. This can be in block form, which is later cut by hot wires to the required dimensions, or moulded into pre-determined product-specific shapes.
EPS is non-hygroscopic - it does not readily absorb or retain moisture from the atmosphere. EPS permits moisture to pass out of a building, resulting in a healthier property with a better internal environment.
My company is interested in your raw material. Can we purchase it in the UK?
Sales of Sunde expandable polystyrene granules are handled in Norway by Ørvar Tollås our Export Manager. To contact him, go to Sundolitt / Contact Us / Sunde Sales or e-mail him on - email@example.com