Packaging and Sustainability

Material Category

Polystyrene

Manner and Scope of the Material’s Use

  • Polystyrene, PS for short, is a widely used synthetic material that is used in many areas of daily life and is used either as a thermoplastic or as a foam (EPS).
  • The technical production of polystyrene was started in 1931. Today, polystyrene is one of the standard synthetic materials and occupies the fourth place in the production sequence after polyethylene, polypropylene and polyvinyl chloride. In the packaging market PS is now behind LDPE, HDPE, PP and PET.

Material Use During Manufacturing

  • Solid polystyrene is clear like glass, hard and electrically insulating. As a packaging material it is especially used where high-quality surfaces and / or brilliant transparency are important.
  • Foamed (expanded) polystyrene (EPS, also known as “airpop”) has a lower mechanical strength and elasticity compared to solid polystyrene. Due to the compressibility it can absorb shock loads well and is therefore suitable for the packaging of sensitive goods. It has a very low thermal conductivity, which makes it superlatively suitable for the widespread use as a thermal insulation material.

Collection / Sorting / Recycling

  • PS is very recyclable into new synthetic materials.
  • PS used for sales packaging in the retail trade is collected by the dual system at households nationwide in Germany.
  • Using near-infrared technology allows the individual types of synthetic materials in the sorting plants to be separated. Today a sorting accuracy of up to 98 % is achieved. This also applies to hard PS. Used EPS packaging is generally good for material recycling. They are taken from the collected goods and delivered to the recycling facilities with special logistics systems due to the low weight.
  • The unmixed PS can be processed to regranulate by mechanical shredding. This is then used in the production of, for example, furniture, hangers or folding boxes and many other things that we find in our everyday life.
  • PS can also be recycled by melting / fusing using an injection molding process. Polystyrene products are well suited for this, as the properties of the material change only slightly after repeated processing.

Development / Background / Outlook

  • By means of the various materials processes, the used synthetic material packaging can either be melted directly to new products or processed to regranulate. This granular recycled synthetic material is a cost-effective alternative to new material and high-quality raw material for the synthetic material processing industry.