Polystyrene
Polystyrene is a polymer made from styrene, a liquid that is commercially manufactured from petroleum, although it is also found in plants.
Polystyrene was first manufactured by BASF in the 1930s, and is used in numerous plastic products. Its most common use, however, is as expanded polystyrene, which is a mixture of about 5% polystyrene and 95% air. This is the material of which coffee cups and takeaway food containers are made. It is also used as insulation in building structures, and also in crafts and model building, particularly architectural models.
In the USA it is made by the Dow Chemical Company under the tradename Styrofoam. The word styrofoam is often used by the general public to indicate any brand of polystyrene foam (see genericized trademark).
The symbol for polystyrene developed by the Society of the Plastics Industry so that items can be labeled for easy recycling is shown on the right. The Unicode character is ♸, which will appear here if you have a suitable font installed: ♸.
