Extruded polystyrene is a type of plastic used to make products ranging from building materials to storage containers. This product may also be referred to as XPS, and is also referred to as Styrofoam® after a popular brand name version of this material. Extruded polystyrene may take the form of a dense foam, or a more solid, plastic-like material, depending on the application.
Manufacturers make polystyrene from hydrocarbon molecules, which are a by-product of the petroleum refining process. The polystyrene particles are then melted at high temperatures, then infused with air. This mixture is placed into a mold, where it is allowed to cool and harden. It may also be subject to a more traditional extrusion process, during which is it pressed through a die to form the desired shape. This manufacturing process gives polystyrene a uniform cell structure and consistent texture throughout the material.
Extruded polystyrene is used to make a number of different products, including both household and industrial goods. It may be molded to form shipping containers for electronics, or shredded to form foam packing peanuts for shipping and mailing. This material is also used to make carryout containers for food, as well as disposable cups and plates. Egg cartons, meat trays and other food storage products are also made from this material, as are insulation and other building materials. Manufacturers may even use extruded polystyrene to make molds or dies for metals and other materials.
This material provides a number of advantages over alternative materials in a variety of fields. Its uniform cell structure gives extruded polystyrene a high level of strength and durability, yet this material is also very lightweight. Extruded polystyrene is also easy to cut and shape to form different products, or for installation on a construction project. It offers a high level of moisture resistance, and is not susceptible to temperature or humidity changes. Extruded polystyrene also provides a high level of versatility in terms of design and application.
One drawback to this material is its cost, especially when compared to alternate materials. When used as a building insulator, XPS typically costs more than traditional fiberglass insulation. When used for food storage, this material comes at a higher price than food containers made from cardboard or some other types of plastic. Extruded polystyrene is also considered a potential threat to the environment. This product takes up a great deal of landfill space, and recycling programs are fairly limited compared to many other forms of plastic.