Polystyrene is a form of chemical compound that is mainly used for a wide variety of packaging. It is an aromaticpolymer made from the monomerstyrene, a liquid hydrocarbon that is manufactured from petroleum by the chemical industry. Polystyrene is one of the most widely used plastics, the scale being several billion kilograms per year.
Many styrenemolecules bond together to make a polystyrene molecule. The squiggly lines show that the long polystyrene molecule goes on farther at both ends.