Very often people mistakenly use the word StyrofoamTM to describe products made of polystyrene foam. However, StyrofoamTM (extruded polystyrene - XPS) is the brand of an insulation board made by DuPont and is not used to manufacture any foam containers such as cups or packaging, which are made from expanded polystyrene (EPS) .
Expanded polystyrene is often not recycled for the following reasons:
- many recycling facilities do not accept it
- it is light and often blown away from recycling bins
- it is bulky, which makes transportation difficult and expensive
- may contain food and be mixed with other plastics
- recycled EPS cannot be used as a component in food containers because of health issues, even after going through a sterilization process
- it is easier and cheaper to produce new EPS than to recycle it
Despite these difficulties, EPS can and should be recycled. One of the ways to recycle EPS waste is to make composites for use in different applications.
In Brazil, Poletto and Zattera from the University of Caxias do Sul (UCS) and Ornaghi from the Sao Paulo State University (UNESP)  compressed EPS wastes, ground the material, and mixed it with wood flour in an extruder. The resulting material was injected into a mold to make wood-plastic composites, and the authors studied their mechanical, thermo-mechanical, and morphological properties. Final products made of recycled EPS-wood composites look like wood, cost less than hardwood, and can be used to make picture frames, park benches, flooring, outdoor furniture, among others.
Oliveira  from the Federal University of São João del Rei (UFSJ) studied the physico-mechanical properties of EPS-cementitious composites. The specific strength and apparent porosity of the composites had little variation and their volumetric and bulk densities decreased. These composites can be used in civil construction applications.
Researchers from the Federal University of Santa Catarina (UFSC), Federal University of Rio Grande do Sul (UFRGS), and University of Moderna Reggio Emilia (UniMore) produced composites made of soda-lime-silica glass and EPS powder beads wastes to be used as thermal insulation , and composites made of recycled ceramic shell and EPS wastes for use in thermal and acoustic applications  with very good results.
Schackow, Effting, Folgueras, and Mendes from the Santa Catarina State University (UDESC) and Güths from the Federal University of Santa Catarina (UFSC)  studied the incorporation of EPS and vermiculite in concrete. The results showed that EPS-concrete composite was lighter and presented higher strength than vermiculite-concrete composite.
Oliveira, Barbosa, Molina, Oliveira, Bertolini, Gava, and Ventorim from the Sao Paulo State University (UNESP) and Christoforo from the Federal University of São Carlos (UFSCar)  studied the sound absorption properties of composites made of gypsum, EPS, and cellulose solid wastes. The results showed that they can be used for acoustic insulation applications.
Moreno and Cidade (Federal University of Santa Maria - UFSM)  developed a silver jewelry collection (a ring, a pair of earrings, and a bracelet) through the lost wax casting process using recycled EPS as a decorative element.
About 34.5% of the EPS waste is recycled in Brazil . Civil construction is the biggest market for EPS recycling, whose waste can be mixed to mortars, light concrete, tiles, flooring, among others. EPS waste can also be used in footwear, furniture, flower pots, etc. .
Finding ways to successfully recycle EPS will require creativity, research, and government support. All of these are critical to the innovation and success of recycling efforts.
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