Polystyrene is a plastic type which is widely used. Thanks to its easy processing and volatility, it has replaced the paper, wood and metals.

Characteristics:
Crystal (general purpose) polystyrene is a transparent and rigid material.

The plastic density is 1,06 gr/cm3, the tensile strain 8000 psi, vicat softening point 106o C, izod impact strength0,2-0,5 ft.1b/inch, lengthening 3%, elasticity modulus 450000 psi.
These characteristics can vary according to the molecular weight and substances used. However the polystyrene for general purpose is a few resistant to UV rays, some chemical substancesand food. Its low vicat temperature of 106o C prevents its widely usage.

The PS resistant to socks are obtained by mass polymerization Dar. Furthermore, elastomers are added to the process. There are two principal processes. The first is a discontinuous process realized in a suspension. The second is a continuous process realized with reactors.

By adding rubber to polystyrene, it is possible to obtain a material with best resistivity to shocks with less rigidity. The types designed for general purposes and resistant are processed with injection molding or extrusion methods. The injection temperature varies between 380-400 F. furthermore, there are also various PS that can be used at different melt flow ranges and different areas.

The rigidity as well as processing easiness of this material facilitates its usage in foam production with high and low pressure process. It is possible to produce signboards, profiles and pipes from the types designed for general purposes and resistant. It is possible to obtain signboards with good polish with the extrusion of crystal polystyrene resistant to shocks. Furthermore, it is also possible to process polystyrene by blending it with other substances. A new application field is the extrusion; thermo-forming process.

Areas of usage:

The dimensions of extrusion equipment are increasing; extruders having thread diameter 6 inch and L/D rate 32:1 are used in signboards production.
They are also widely used as insulating materials, recipients with thin walls, cooling towers, foam tube, rubber, various tools, automobile parts, panels and plastic parts of electronic equipments.
They are frequently used in disposable glasses, plates, yogurt cans as well as ayran cans.
It is also used in the recipients used for cell culture which is one of the basic application of genetic and molecular biology.