Expanded Polystyrene (EPS) is a lightweight, rigid cellular plastic foam insulation material derived from polystyrene beads. Through an innovative expansion process, small polystyrene beads containing pentane gas are exposed to steam, causing them to expand to approximately 40 times their original volume and create a structure of individual closed cells. This unique manufacturing process results in a material that is remarkably lightweight while maintaining excellent thermal insulation properties. EPS’s closed-cell structure creates trapped air pockets that significantly reduce heat transfer, making it an ideal choice for building insulation, protective packaging, and food service applications. The material’s versatility is enhanced by its moldability, allowing manufacturers to create custom shapes and sizes through a secondary heat treatment process using specific molds.