
POLYSTYRENE (PS)
Polystyrene (PS) is a synthetic aromatic hydrocarbon polymer made from the monomer known as styrene. Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It is a poor barrier to oxygen and water vapor and has a relatively low melting point. Polystyrene is one of the most widely used plastics, the scale of its production being several million tonnes per year. Polystyrene can be naturally transparent but can be colored with colorants. Uses include protective packaging (such as packing peanuts and in the jewel cases used for storage of optical discs such as CDs and occasionally DVDs), containers, lids, bottles, trays, tumblers, disposable cutlery, and in the making of models.
Polystyrene (PS) plastic is a naturally transparent thermoplastic that is available as both a typical solid plastic as well in the form of a rigid foam material. PS plastic is commonly used in a variety of consumer product applications and is also particularly useful for commercial packaging. Dow Chemical Company invented a proprietary process to make their trademarked and well-known polystyrene foam product “styrofoam” in 1941. The material is somewhat controversial amongst environmental groups because it is slow to biodegrade and is increasingly present as outdoor litter (particularly in the form of foam floating in waterways and the ocean).
The solid plastic form of polystyrene is commonly used in medical device applications like test tubes or Petri dishes, or in day-to-day items like the housing on your smoke detectors, the case you used to buy your CDs in, and frequently as a container for foods like yogurt or the red “solo” cup you drink from at a tailgate and/or when you’re losing in a game of beer-pong.
Polystyrene properties
Property |
Value |
Technical Name |
Polystyrene (PS) |
Chemical Formula |
(C8H8)N |
Melt Temperature |
210-249 °C (410-480 °F) *** |
Typical Injection Molding Temperature |
38 - 66 °C (100 - 150 °F) *** |
Heat Deflection Temperature (HDT) |
95 °C (284 °F) at 0.46 MPa (66 PSI) ** |
Tensile Strength |
53 MPa (7700 PSI) *** |
Flexural Strength |
83 MPa (12000 PSI) *** |
Specific Gravity |
1.04 |
Shrink Rate |
0.3 - 0.7 % (.003 - .007 in/in) *** |
PolyStyrene Grades
-Poly Styrene is a product in EPS 100, EPS R 200, EPS R 300, GPPS 1540, GPPS 1551, GPPS 1160, and HIPS 7240
-EPS F 100
Expandable Polystyrene is a thermoplastic material, lightweight, resilient, foamed plastic composed of hydrogen and carbon atoms.
Application:
Insulation, big packing, Products
-GPPS 1540
GPPS 1540 is easy flowing crystal polystyrene designed for extrusion or injection applications. In extrusion, it improves extruder output and thermoforming cycle time when mixed with super high impact polystyrene such as HIPS 7240. It is particularly suitable for glossy-layer co-extrusion.
Applications:
Extrusion: Impact dilution; Gloss layer in co-extrusion; Anionic styrene-butadiene copolymer dilution.
Injection: Packaging articles; Medical applications,e.g., Petri dishes; Office equipment; Pen barrels; Crisper boxes for refrigerators; Cups
-GPPS 1160
GPPS1160 is high heat resistance and molecular weight crystal polystyrene for extrusion and bi-oriented polystyrene industry. It is particularly useful in the production of the thick sheets by direct-inject gassing.
GPPS 1160 can also be used in dilution with HIPS 7240 for extrusion of the sheet for thermoforming.
This Grade has food contact approval.
Applications:
Shower cabinets, lighting thin films, insulation board, foam sheet of fruits trays, meat trays, egg boxes
-GPPS 1551
GPPS 1551 is normal flow polystyrene designed for extrusion or injection applications.
Applications:
Houseware, Containers, toys, office stationary, etc