What is the difference between Polyurethane foam, Molded EPS Polystyrene and Extruded Polystyrene foam?
(These are the 3 foams that Usblanks will offer…) Polyurethane and Polystyrene foams differ in their chemical makeup. Chemical makeup aside, the three foams that you ask about are different in their cell structure. Both extruded polystyrene foam (XPS) and Polyurethane (PU) foam are a closed cell type foam, which is made up of a suspension of tiny bubbles. Expanded Polystyrene (EPS) foam consists of small beads of polystyrene that have been stuck together. Many are familiar with EPS foam as is commonly used for foam cups and beer coolers. PU foam can be glassed using epoxy resins and polyester resins, whereas XPS and EPS foam can only be glassed with epoxy resins. EPS and XPS resins will react with polyester resins. All foams come in different densities. FYI – – On a side note, there are two different polyurethane (PU) foams to be on the lookout for, one is a tolulene-di-isocynate (TDI) base, and the other is made using methylene di isocynate (MDI), a less toxic chemical. You should a
