Styrofoam is a

trademark A trademark (also written trade mark or trade-mark) is a type of intellectual property consisting of a recognizable sign, design, or expression that identifies products or services from a particular source and distinguishes them from oth ...

ed brand of closed-cell

extruded polystyrene foam Polystyrene (PS) is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene. Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It i ...

(XPS), commonly called "Blue Board", manufactured as foam continuous

building insulation Building insulation is any object in a building used as insulation for thermal management. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact ins ...

board used in walls, roofs, and foundations as

thermal insulation Thermal insulation is the reduction of heat transfer (i.e., the transfer of thermal energy between objects of differing temperature) between objects in thermal contact or in range of radiative influence. Thermal insulation can be achieved with ...

and water barrier. This material is light blue in color and is owned and manufactured by DuPont. DuPont also has produced a line of green and white foam shapes for use in crafts and floral arrangements. ''Styrofoam'' is colloquially used worldwide to refer to another material that is usually white in color and made of expanded (not extruded) polystyrene foam (

EPS EPS, EPs or Eps may refer to: Commerce and finance * Earnings per share * Electronic Payment Services, in Hong Kong, Macau, and Shenzhen, China * Express Payment System, in the Philippines Education * Edmonton Public Schools, in Edmonton, Al ...

). It is often used in food containers, coffee cups, and as cushioning material in packaging. The trademarked term is used generically although it is a different material from the extruded polystyrene used for Styrofoam insulation. Additionally, it is moderately soluble in many organic solvents, cyanoacrylate, and the propellants and solvents of spray paint.

History

In the 1940s, researchers, originally at Dow's Chemical Physics Lab, led by Ray McIntire, found a way to make foamed

polystyrene Polystyrene (PS) is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene. Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It is ...

. They rediscovered a method first used by

Swedish Swedish or ' may refer to: Anything from or related to Sweden, a country in Northern Europe. Or, specifically: * Swedish language, a North Germanic language spoken primarily in Sweden and Finland ** Swedish alphabet, the official alphabet used by ...

inventor Carl Georg Munters, and obtained an exclusive license to Munters's

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an sufficiency of disclosure, enabling disclo ...

in the United States. Dow found ways to adapt Munters's method to make large quantities of extruded polystyrene as a closed cell foam that resists moisture. The patent on this adaptation was filed in 1947.

Uses

Styrofoam has a variety of uses. Styrofoam is composed of 98% air, making it lightweight and buoyant. DuPont produces Styrofoam building materials, including varieties of

sheathing and pipe insulation. The claimed R-value of Styrofoam insulation is five per inch. Styrofoam can be used under roads and other structures to prevent soil disturbances due to freezing and thawing. DuPont also produces Styrofoam blocks and other shapes for use by florists and in craft products. DuPont insulation Styrofoam has a distinctive blue color; Styrofoam for craft applications is available in white and green.

Environmental issues

The

EPA The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it be ...

and International Agency for Research on Cancer reported limited evidence that styrene is

carcinogen A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive subst ...

ic for humans and experimental animals, meaning that there is a positive association between exposure and cancer and that causality is credible, but that other explanations cannot be confidently excluded. See also the expansive list of environmental issues of Polystyrene, among those it being non-biodegradable.

References

External links

{{sisterlinks, c=Extruded polystyrene, d=Q1194725, s=no, b=no, q=no, n=no, v=no, voy=no, m=no, mw=no, species=no
Bio-Styrofoam from cellulosic crystals, better insulator than styrofoam and supports 200 times its weight
Dow Chemical Company Foams Plastic brands Brand name materials Brands that became generic Building insulation materials Organic polymers Swedish inventions 1941 in technology Products introduced in 1941 American inventions