Thermoplastic foams include polystyrene, polyethylene, and polypropylene. Polystyrene foams are commonly used in food service and food packaging as well as extruded insulation (XPS) board. Polyethylene and polypropylene foams are used as pipe insulation and in many packaging applications.
Thermoset foams include polyurethane, polyisocyanurate, and phenolic. Typical applications for polyurethanes are appliance insulation, integral skin foams such as shoe soles, and insulated metal panels and doors. Polyisocyanurate and phenolic foams are used in applications where building codes require less combustible materials such as roofing insulation and exterior wall sheathing.