Foam Manufacturing Process

Polystyrene Foam

Polystyrene foam, often known as Styrofoam, is made from petroleum by-products called styrenes. The process of turning styrenes into foam is known as polymerization. First the styrene is infused with hydrocarbon gas, which causes the molecules to expand. The hydrocarbon-infused styrene is then heated to further expand each molecule, then placed in a mold. The mold is heated with steam to cause the styrene to take the shape of the mold once it is released. This process is used to produced packing foam and building insulation. The resulting foam material is often known as expanded polystyrene (EPS) and is commonly called "beadboard."

Polyurethane Foam

Polyurethane foam is manufactured from man-made particles called polymers. The polymers are joined by urethanes, or carbamates, and stored as a liquid in large vats. The vats are continuously agitated to keep the solution mixed and ready for production. To produce polyurethane foam, the liquid is heated and pumped into a series of pipes, where it is sprayed out onto sheets of heavy paper. Once it has been sprayed, it is infused with carbon dioxide gas, which causes it to rise like bread dough. Additional sheets of paper are added to form the foam into the desired shape, and it is then cooled and cut to the desired length. Polyurethane foam is often found in mattresses and other furnishings, and rigid units are used in flower arrangements.

Polyethylene Foam

Polyethylene foam is an extruded product made from a thermoplastic compound called ethene. The liquid ethene is heated and drawn through a series of molds or dies to create the desired shape. Large sheets of ethene are called "buns," and may be placed into molds and heated to form a variety of products. Soft polyethylene foam us used as padding in shoes and carpeting, while rigid versions are often used in sculpture or insulation.

References

• Polyurethane Foam Slideshow
• Foam Facts
• Making Polyurethane Foam