Plastics Profiler-High Impact Polystyrene

June 6, 2021 | Newsletter, Plastics Profiler

High impact polystyrene (HIPS) is an amorphous thermoplastic produced by dissolving 5-7% polybutadiene rubber in styrene monomer before bulk polymerization that results in a compound with the following characteristics:

  • High Impact Strength
  • Good Stiffness
  • Dimensional Stability
  • Ease of Processing

Impact strength increases for grades with higher butadiene content (1.0-5.0 ft-lb/in), but the highest impact grades have lower tensile and flexural properties. The water absorption rate is low so pre-drying is not required and the material flow characteristics are excellent. As an amorphous material low mold shrinkage rates (0.003-0.007 in/in) allow for very good dimensional stability. Drawbacks include poor inherent flammability and heat deflection properties limiting its use in automotive applications.

AGS Technology injection molds cost effective, general purpose HIPS into product displays, office products, brackets, fittings and other applications found in construction, industrial and consumer good industries.  To reference the product data sheet for high impact polystyrene click on Injectoblend FHIPS108.