Ordinary polystyrene resin is an amorphous polymers, polystyrene polymer chain side groups for benzene, random arrangement of large volume base for the benzene ring determines the physical and chemical properties of polystyrene, such as transparency. stiffness. high glass transition temperature, brittle. Expandable polystyrene for the low boiling point of physical immersion in GPS vesicant, heat in the processing of foam, designed for the production of foamed plastic products. For high impact polystyrene copolymer of styrene and butadiene, butadiene is the dispersed phase, improve impact strength of materials, but the product is not transparent. Syndiotactic polystyrene with the structure produced using metallocene catalysts, polystyrene in the development of new varieties, properties, belonging to engineering plastics.