SWhat is the Difference Between Styrofoam™ and Polystyrene?
Like Typex, Q-tip or Kleenex, Styrofoam has become a household name to refer to polystyrene products, however this is a huge, common, misconception.
Styrofoam™ is a Dow trade name and is actually blue in colour. It is an extruded polystyrene (XPS) made for thermal insulation, construction and craft applications.
The white stuff that people see at canteens, in packaging and more, is EPS- expanded polystyrene. EPS is available in various densities and forms for insulation, construction and craft applications and so much more. The applications of EPS are literally endless and can range from a drinking cup to packaging to helmets, theatre props, automobile parts, medical equipment, electronics, craft and signage to massive blocks for insulation or retaining walls.
So, while both are polystyrene products and are used for some similar applications, that is where the similarity stops.
What is the difference between styrene and polystyrene?
The difference is chemistry.
Styrene is a liquid that can be chemically linked to create polystyrene, a solid plastic that displays different properties.
Expanded Polystyrene – EPS- Structure
Polystyrene is made by stringing together, or polymerizing, styrene, a building-block chemical used in the manufacture of many products.
Styrene occurs naturally in foods such as strawberries, cinnamon, coffee and beef. Its chemical structure is similar to cinnamic aldehyde, the chemical component that creates cinnamon’s flavor.
EPS foam is composed of organic elements – carbon, hydrogen and oxygen – and does not contain chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs).
Polystyrene consists of 96% air, which makes it incredibly lightweight.
EPS IS recyclable!
Unfortunately, the white stuff is taking a beating in the news with another big misconception but that couldn’t be further from the truth.
Expanded polystyrene is a material that is not commonly recycled, although a few councils may accept it at household waste recycling centres. Whilst it is a positive attribute that greatly reduces carbon emissions during transportation, it also causes polystyrene products to easily be blown away by wind if not properly transported.
Few people are aware that polystyrene is a valuable resource that is readily recycled in South Africa. Waste management companies collect and supply post-consumer and post-industrial polystyrene products such as meat trays, hamburger clamshells and coffee cups to recyclers who use it to manufacture stationery, hangers, picture frames, cornices, curtain rods and skirtings. In the most recent development it is mixed with a special cement mixture for use in building and construction.
Expanded Polystyrene has always been CFC- and HCFC-free
What About Food?
All food packaging – glass, aluminium, paper and plastics (such as polystyrene) – contains substances that can “migrate” in very tiny amounts to foods or beverages.
FDA has for decades stated that polystyrene is safe for use in contact with food. The European Commission/European Food Safety Authority and other regulatory agencies have reached similar conclusions.
Exposures to styrene from the use of polystyrene food contact products estimated daily intake is 6.6 micrograms per person per day. This is more than 10,000 times below the safety limit set by FDA (FDA’s acceptable daily intake value of styrene is calculated to be 90,000 micrograms per person per day).