styrenu

Styrenu, commonly known as styrene, is an aromatic hydrocarbon with the chemical formula C8H8. It is a colorless, volatile liquid at room temperature with a sweet, petrochemical odor. Styrene is primarily used as the monomer for polystyrene and many copolymers.

Industrial production occurs mainly by catalytic dehydrogenation of ethylbenzene, a process that converts ethylbenzene to styrene and hydrogen. The feedstock ethylbenzene is typically derived from benzene and ethylene. Crude styrene is purified by distillation and stabilized with inhibitors to prevent uncontrolled polymerization during handling and storage. Common inhibitors include tert-butylcatechol or hydroquinone; polymerization is exothermic and storage requires appropriate controls.

Styrene has a boiling point around 145°C and a melting point around -30°C. It is sparingly soluble in water and highly soluble in many organic solvents. It is flammable and presents a vapour hazard; it readily evaporates at room temperature. Styrene readily undergoes free-radical polymerization, which is the basis for polystyrene production; therefore inhibitors are added in commercial monomer.

Applications include the principal building blocks for polystyrene resins (general purpose and high-impact grades), expanded polystyrene foam, and copolymers such as styrene-butadiene rubber, acrylonitrile-styrene, and styrene-acrylonitrile resins. It is also used in manufacturing resins, elastomers, adhesives, coatings, and some specialty additives.

Safety and environment: Exposure to styrene primarily affects the nervous system and can cause headaches, dizziness, and fatigue at high levels; long-term exposure is under evaluation for carcinogenic risk. It is classified as possibly carcinogenic to humans by some agencies. It is a volatile organic compound and a pollutant that can contribute to ground-level ozone formation. Handling requires ventilation, cooling, and avoidance of peroxide formation; monomer stocks include inhibitors and storage away from oxidizers.