Polystyrene is a type of plastic made from petroleum by-products. It is formed from hydrocarbon molecules, which take the shape of tiny foam particles after heating and processing. These foam particles, or beads, are large enough to be visible to the eye, yet small and lightweight enough to be used in a wide variety of applications. While many people associate polystyrene beads with beanbag filler, they are also used to make products ranging from building insulation to packaging materials. Outside of manufacturing, they are also widely used to control mosquitoes and other pests.
One of the most common uses for polystyrene beads is as a filler material in consumer goods. These beads are used in most beanbag chairs, as well as small foot bags, pet beds, and pillows or cushions. They also serve as a popular filler material for stuffed animals and other toys. When used as a filler material, the beads are poured into an outer shell or casing without the use of any resins or adhesives.
Polystyrene beads may serve as wall cavity insulation in homes and building. They are particularly effective when installed in existing walls, where it may be impractical to add traditional fiberglass blankets. Installers cut a small hole in the drywall or plaster, then inject the polystyrene into the wall using an air blower. The beads fill up all the available space and easily fit around pipes, wires, and other obstructions. Polystyrene insulation helps to improve comfort and energy efficiency in a building, which helps to keep energy costs low and preserve fossil fuels.
Loose beads are also used to slow the growth of mosquito populations, which helps to control diseases like malaria. These beads are poured into septic tanks or latrine pits to interrupt the respiration patterns of mosquito larvae. The layer of floating polystyrene also prevents adult mosquitoes from exiting these breeding grounds. Unlike alternate materials, polystyrene beads remain on the surface of the water until they are washed away. They may also be use in wet or spongy soil, or simply around planting beds.
The beads may be molded together to form expanded polystyrene foam (EPS). This foam serves as a popular packaging material, while small foam peanuts can be used to cushion objects during shipping. Beads can also be pressed into thin sheets of foam, which are used to insulate walls, roofs, or even refrigeration units.