POLYSTYRENE (Click for Properties & Specs)
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Polystyrene (PS) is a thermoplastic that is designed for applications requiring excellent electrical and mechanical properties together with good processability. Polystyrenes have well-balanced physical properties and are generally transparent, but available in various colors.

Polystyrenes are usually processed by injection molding, but due to the material's excellent processability, other methods work equally well, including blow and vacuum molding, thermoforming, extrusion or compression molding, and machining. PS grades are resistant to a wide variety of chemicals: alkalies, salts, lower alcohols, and weak acids. Polystyrenes also comply with FDA regulations.

General Purpose Polystyrene (GPPS)
GPPS has excellent transparency, good water resistance, and a high dielectric strength. It is widely used for laminated electronic circuits, high frequency insulation sheeting, insulators and other electrical applications.

High Impact Polystyrene (HIPS)
HIPS has good dimensional strength, balanced properties of impact strength and heat resistance, is easily machined, and is relatively low cost. Because of its good impact strength at low temperatures, it is typically used for home appliances, toys, and electrical components.
 
TYPICAL PROPERTIES of POLYSTYRENE

NOTE: All values are average test results from typical production material. No warranty is implied or guaranteed and testing is recommended for each application.

 ASTM or
 UL Test      Property Tested                    GP-PS               HI-PS
PHYSICAL  
 D792         Density (lb/in³)                   0.043               0.043
 D792         Density (g/cm³)                    1.05                1.04
 D570         Water Absorption, 24 hrs (%)       0.06                0.01
MECHANICAL
 D638         Tensile Strength (psi)             7,500               4,000
 D638         Tensile Modulus (psi)              450,000             260,000
 D638         Tensile Elongation at Break (%)    47                  55
 D790         Flexural Strength (psi)            6,100               8,700
 D790         Flexural Modulus (psi)             475,000             280,000
 D695         Compressive Strength (psi)         14,500              7,500
 D785         Hardness, Rockwell                 75M                 56L
 D256         IZOD Impact Notched (ft-lb/in)     0.8                 2
THERMAL			
 D696         Coefficient of Linear Thermal 
              Expansion(x 10-5 in./in./°F)       4.0                 4.2
 D648         Heat Deflection Temp 
              (°F / °C)at 264 psi                200 / 95            195 / 92
 D3418        Vicat Softening Temp (°F / °C)     224 / 107           214 / 102
 -            Max Operating Temp (°F / °C)       150 / 65            140 / 60
 C177         Thermal Conductivity
              (BTU-in/ft²-hr-°F)                 --                  --
              (x 10-4 cal/cm-sec-°C)             --                  --
 UL94         Flammability Rating                H-B                 H-B
ELECTRICAL
 D149         Dielectric Strength (V/mil) 
              short time, 1/8" thick             60                  45
 D149         Dielectric Constant at 1MHz        2.5                 2.7
 D495         Arc Resistance (sec)               70                  100
 D257         Volume Resistivity 
              (ohm-cm) at 50% RH                 >1016               >1016
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