Damage on a box made from sheet polystyrene, 20th century.

Damage on one of the twelve different coloured polystyrene samples formed into boxes. Polystyrene is a thermoplastic made by the polymerisation of styrene. It is an excellent electrical insulator, and is relatively unaffected by exposure to water. It has many applications including toys, light fittings, pens, lenses and light industrial components. Polystyrene can also be extruded in sheets for use in window envelopes and as a packaging material, as well as being foamed to form the lightweight packaging as which the versatile plastic is probably most familiar.