HIPS

WHAT IS HIGH-IMPACT POLYSTYRENE?

High-impact polystyrene is plastic used in many everyday items. It’s known for its strength, crack-resistance and use in low-heat settings. Products made from high-impact polystyrene are marked by a “6” within a solid triangle – its resin identification code. This is usually found on or near the bottom of the product.

High-impact polystyrene starts as a liquid monomer and is transformed into a stable, solid polymer. It’s then used to produce cups and lids through thermoforming or injection molding.

Thermoforming

requires laying an extruded sheet of plastic over a mold. Then heat and suction are used to form the plastic into the shape of the mold. Once shaped, these sheets are cooled and trimmed to create the finished product.

Injection molding

forces melted plastic into a mold cavity. The product is then cooled, ejected from the mold and trimmed.

RECOVERING & RECYCLING HIGH-IMPACT POLYSTYRENE

High-impact polystyrene can be recycled. Recycling facilities are limited at this time; however, access is increasing in the US and Canada. Packaging that is less than 2”x2”x2” or black in color is unlikely to be recovered at typical sorting facilities.

For the most accurate information, we recommend checking with your local municipality or waste hauler to see if high-impact polystyrene is accepted in your community’s recycling program.

High-impact polystyrene cups can be recycled through certain mail-in programs, like TerraCycle’s Zero Waste Box™. You may also search for high-impact polystyrene container recycling by zip code or mail-back program at Earth911.