Editing Styrofoam

{{Short description|Trademarked brand for extruded polystyrene}}
{{about|the Styrofoam brand|other materials sometimes referred to as "Styrofoam"|extruded polystyrene foam|and|expanded polystyrene|other uses|Styrofoam (disambiguation)}}
[[File:Styrofoam-grey-board.jpg|thumb|Styrofoam insulation extruded polystyrene foam (XPS), owned and manufactured by DuPont]]
'''Styrofoam''' is a brand of closed-cell [[polystyrene#Extruded polystyrene foam|extruded polystyrene foam]] (XPS), manufactured to provide continuous [[building insulation]] board used in walls, roofs, and foundations as [[thermal insulation]] and as a 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.<ref name="nocup">{{cite web|url=http://craft.dow.com/craft/about/cup.htm|archive-url=https://web.archive.org/web/20051201163706/http://craft.dow.com/craft/about/cup.htm|title=You can't drink coffee from a STYROFOAM cup.|archive-date=2005-12-01|publisher=The Dow Chemical Company}}</ref>

[[File:Pueblo Chemical Agent-Destruction Pilot Plant, Static Detonation Chamber Assembly Site (48879909448).jpg|thumb|Worker installing Styrofoam frost protection insulation board.]]

The term ''styrofoam'' has become a [[Generic trademark|genericized trademark]]; it is often used in the United States as a colloquial term to refer to expanded (not extruded) [[polystyrene|polystyrene foam]] ([[Expanded polystyrene|EPS]]).<ref name="gc">{{cite web |url= https://www.genericides.org/trademark/styrofoam|title= Has styrofoam become a generic trademark?  |access-date= April 29, 2021 |website= genericides.org |date= 31 January 2020 }}</ref> Outside the United States, EPS is most commonly referred to as simply "polystyrene" with the term "styrofoam" being used in its capacity to describe all forms of extruded polystyrene, not just the Dupont brand itself. Polystyrene (EPS) is often used in [[foam food container|food containers]], coffee cups, and as [[cushioning]] material in [[packaging]].<ref name="what-is-styrofoam">{{Cite web |date=March 24, 2008 |title=What is STYROFOAM? |url=http://building.dow.com/styrofoam/what.htm |archive-url=https://web.archive.org/web/20080324134328/http://building.dow.com/styrofoam/what.htm |archive-date=2008-03-24}}</ref><ref name="nocup"/> Styrofoam is, however, a far less dense material than EPS and is more commonly suited to tasks such as thermal [[Thermal insulation|insulation]].<ref name="gc"/>

Additionally, it is moderately soluble in many organic solvents, [[super glue|cyanoacrylate]], and the propellants and solvents of [[spray paint]]. 

== History ==
In the 1940s, researchers, originally at [[Dow Inc.|Dow]]'s Chemical Physics Lab, led by [[Ray McIntire]], found a way to make foamed [[polystyrene]]. They rediscovered a method first used by [[Sweden|Swedish]] inventor [[Carl Georg Munters]], and obtained an exclusive license to Munters's [[patent]] in the United States.<ref>{{cite book
 | last = Boundy
 | first = Ray H.
 |author2=Amos, J. Lawrence
 | title = A History of the Dow Chemical Physics Lab
 | publisher = Marcel Dekker, Inc.
 | year = 1991
 | location = New York
 | pages = 117–128
 | isbn = 0-8247-8097-3}}</ref> 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.<ref>{{cite patent |country=US |number=2450436 |status= |title=Manufacture of cellular thermoplastic products |pubdate=1948-10-05 |gdate=1948-10-05 |fdate=1947-07-26 |pridate= |inventor=Otis Ray McIntire |invent1= |invent2= |assign1= |assign2= |class= |url=}}</ref>

== Uses ==

Styrofoam has a variety of uses. Styrofoam is composed of 98% air, making it lightweight and buoyant.<ref>{{cite web| url= http://www.forte-eps-solutions.com/styrofoam-sheets-polystyrene-insulation-difference-new-jersey-new-york-ontario-quebec.html|title= What is the Difference between EPS Polystyrene and (styrofoam)?}}</ref>

DuPont produces Styrofoam building materials, including varieties of [[building insulation]] sheathing and pipe insulation. The claimed [[R-value (insulation)|R-value]] of Styrofoam insulation is approximately 5 °F⋅ft<sup>2</sup>⋅h/BTU for 1 inch thick sheet.<ref>{{Cite web |title=Dow Announces New Technology for STYROFOAM Insulation |url=http://building.dow.com/media/news/2007/20071205a.htm |archive-url=https://web.archive.org/web/20110812230057/http://building.dow.com/media/news/2007/20071205a.htm |archive-date=2011-08-12}}</ref>

Styrofoam can be used under roads and other structures to prevent soil disturbances due to freezing and thawing.<ref>{{cite web|url=http://building.dow.com/na/en/applications/geotech/index.htm|title=Geotechnical applications of Styrofoam|publisher = Dow Chemical| access-date=2009-10-28}}</ref><ref>{{cite web|url=http://www.alaskool.org/resources/regional/nw_reg_pro/permafrost.html|title=Engineering considerations when building on permafrost|access-date=2007-08-30}}</ref>

DuPont also produces Styrofoam blocks and other shapes for use by [[florist]]s and in craft products.<ref>{{cite web|url=http://craft.dow.com|title=STYROFOAM Brand Foam Crafts| access-date=2010-12-31}}</ref> DuPont insulation Styrofoam has a distinctive blue color; Styrofoam for craft applications is available in white and green.<ref name="nocup"/>

== Environmental issues ==
The [[EPA]] and [[International Agency for Research on Cancer]] reported limited evidence that [[styrene]] is [[carcinogen]]ic for humans and [[experimental animal]]s, meaning that there is a positive [[statistical association|association]] between exposure and cancer and that causality is credible, but that other explanations cannot be confidently excluded.<ref>{{cite web
 |title       = (Styrene) Fact Sheet: Support Document (CAS No. 100-42-5)
 |url         = http://www.epa.gov/chemfact/styre-sd.pdf                                            |date        = December 1994
 |archive-url = https://web.archive.org/web/20150924043958/http://www.epa.gov/chemfact/styre-sd.pdf |archive-date= 24 September 2015   |access-date = 8 January 2020
 |website     = [[EPA]]
 }}
</ref><ref>{{cite web
 |title       = STYRENE (Group 2B)
 |url         = http://www.inchem.org/documents/iarc/vol82/82-07.html                               |year        = 2002                |access-date = 8 January 2020
 |website     = [[INCHEM]]
 }}</ref>

See also the expansive list of [[Polystyrene#Environmental issues|environmental issues of polystyrene]], among which it being non-biodegradable.

== See also ==
* [[List of generic and genericized trademarks]]
* [[National Inventors Hall of Fame]]
* [[Resin identification code]]
* [[Structural insulated panel]]

== References ==
{{Reflist}}

[[Category:Dow Chemical Company]]
[[Category:Foams]]
[[Category:Plastic brands]]
[[Category:Brand name materials]]
[[Category:Brands that became generic]]
[[Category:Building insulation materials]]
[[Category:Organic polymers]]
[[Category:Swedish inventions]]
[[Category:1941 in technology]]
[[Category:Products introduced in 1941]]
[[Category:American inventions]]