Polystyrene is a polymerization product of styrene (vinyl benzene), thermoplastic polymer of linear structure. It is widely used due to its good physical and mechanical properties, environmental safety, chemical inertness to many substances, moisture-, electricity- and frost-resistance.

It is produced in the form of transparent cylindrical granules, which are processed into finished products by way of injection molding or extrusion at 190-230°C. Polystyrene (PS) and PS-based plastics are extensively used due to its low cost, ease of processing and a wide range of grades.

High-impact polystyrenes, i.e. styrene copolymers with butadiene and styrene-butadiene rubber, are used most widely (more than 60% in the production of polystyrene plastics). There are also lots of other modifications of styrene copolymers.