Polystyrene Sphere

This single, gobstopper-sized, feather-light white ball is made of expanded polystyrene beads, heat-fused to form a delicate, plastic foam sphere. In large quantities, these balls tend to generate static electricity and leap out of your grasp, perhaps explaining why this one is somewhat dented. The ball itself is formed in a mould and comes pre-pierced, for use in craft or model-making as a core for objects requiring mass with low density and lightness. Expanded polystyrene seems to be a cheap option for industry, as in coffee-cups and moulded packaging, but strangely expensive for art and craft use. 

Polystyrene is a vinyl polymer that was initially discovered in the early 19th century during experiments with storax, the resin of the Turkish Liquidambar tree. Large scale production of polystyrene was made possible by changing the raw material from naturally derived storax to synthetically derived ethylbenzene, as this meant synthetic styrene could be produced from processing crude oil. Ethylbenzene is still widely used today, contributing to 90% of polystyrene production.

Expanded polystyrene is technically recyclable but it cannot go into household recycling because it crumbles easily and lacks large-scale sorting infrastructure so putting it in your home bin contaminates other materials. As a result we throw it away in vast quantities, in land-fill sites and into the sea, where it is found piled up on shorelines, and in the stomachs of marine creatures.

Read our profiles on polystyrene balls and packing peanuts to learn more about the history and manufacturing processes behind this wonderfully lightweight but controversial material.