Polystyrene is produced from styrene, which was first distilled from tree resin in 1839. It is prepared through the polymerization of styrene, which can be done through various techniques like solution polymerization. Polystyrene has good thermal insulation properties and is used in many applications like building insulation, food packaging, toys, and more. It is chemically inert but dissolves in some organic solvents and is flammable.