PolystyreneEPS (Sintered Expanded Polystyrene) is a material produced from styrene, a monomer derived from petroleum, but also found in foods such as wheat, strawberries, meat and coffee. Polystyrene is obtained through the polymerization of styrene. Before being expanded the polystyrene is in glassy granule form (beads), with size ranging from 0.3 to 2.8 mm.