Industrially, polystyrene polymers are synthesized in a similar way that will be performed in this lab: benzoyl peroxide is used as an initiator in the polymerization process of styrene monomers. Commercial polystyrenes are a family of thermoplastic materials that possesses a wide range of properties suitable for many diverse applications. In the process economics of producing polystyrene, these properties depend on the recipe for the polymerization of styrene, the additives or impurities present in the polymer, and the fabrication methods that give the polymer its final form.