Polystyrene is the product of the polymerization reaction of styrene monomer, a polymer compound. Polystyrene was first obtained from a volatile oil in the natural resin balsam. 1930, the German company Farben was first produced on a trial basis by continuous ontogenetic polymerization, followed by industrial production, is the early development of plastic varieties. 1982 annual production is second only to polyethylene and polyvinyl chloride.

　　Styrene is mainly produced by dehydrogenation of benzene and ethylene by hydrocarbonization, and the monomer can be polymerized either by free radical reaction process or by ionic reaction process, and the properties and applications of the resulting products vary greatly depending on the type of reaction and polymerization method. Free radical polymerization of random polystyrene, temperature resistance of only 80 ℃; negative ion coordination polymerization of isotactic polystyrene (phenyl in the same side of the carbon chain plane) heat-resistant up to 240 ℃.

　　The body polymerization can be obtained glassy transparent, excellent insulation properties of rigid plastics; solution polymerization is mostly used to make coatings. Polystyrene has good corrosion resistance to acids, alkalis, salts, mineral oils, organic acids, low grade alcohols, etc., but softening or dissolution occurs in acetone, esters, aromatic hydrocarbons and other organic solvents. Good insulation, transparent, high folding Chemicalbook light rate, water resistance, good coloring, can be made into a variety of brightly colored plastic products. Melt thermal stability and fluidity is very good, easy to process, can be molded, extrusion molding.

　　Polystyrene film can be used as the insulation layer of capacitors and electrical parts, foam can be used as packaging materials for precision instruments, construction of sound insulation, shockproof materials. However, polystyrene is brittle, poor temperature resistance, low surface hardness, so its application is limited. For this reason, often through copolymerization or blending and other methods to improve its performance and expand the range of applications. A small amount of rubber blended with polystyrene can significantly improve the impact resistance. Styrene and butadiene random copolymer - styrene-butadiene rubber is widely used as automotive tires. Copolymerization with acrylonitrile can improve the softening point of the product, without reducing its transparency. Terpolymer ABS is an excellent engineering plastic. Styrene and butadiene block copolymers are widely used thermoplastic elastomers. Copolymerization with divinylbenzene can produce the parent of various ion exchange resins.

　　The benzene ring on polystyrene can be used in various chemical reactions to produce polymers with a polystyrene backbone and various functional groups as polymer reagents or polymer catalysts.