HDPE -High Impact Polyethylene

High Impact Polystyrene is what its name implies. A few cents more than crystal styrene, to pay for the rubber modifier. HIPS is opaque and very widely used. It has a lower modulus, better elongation, and is a lot less brittle than crystal styrene.

Applications: Household Goods, Containers, Furniture, Housings and Packaging.

Tensile Strength Flexural Modulus Impact Strength Max Temp. Chemical Resistance
7,500-10,000 psi 160,000 -370,000 psi 3-7 ft-lb/in notched izod 100°-150° F Poor


  • Optical clarity
  • High gloss
  • FDA grades available
  • Low cost
  • Good dimensional stability
  • Good rigidity


  • Flammable, but flame retardant grades available
  • Poor solvent resistance
  • Homopolymers are brittle
  • Subject to stress and environmental cracking

Brand Names: Certene, Hival, Polystyrol, Styron