Extruded Polystyrene Foam vs. Styrofoam: What's the Difference?

We hate to break it to you, but a lot of the things that people think are made of styrofoam are actually made of polystyrene. Styrofoam is a trademarked brand of closed-cell extruded polystyrene foam, or XPS. This foam is also referred to as “Blue Board” and is used for building insulation, thermal insulation and water barriers. Styrofoam is owned and manufactured by The Dow Chemical Company.

So, just what is styrofoam made of? Styrofoam is made out of styrene which is a petroleum-based product. How is styrofoam made? Through polymerization, styrene is refined into polystyrene and then a hydrofluorocarbon agent is added. This combination is then extruded and allowed to expand under pressure until it forms a foam board.

So, If It's Not Styrofoam, What Is It?

The foam that you formerly knew as styrofoam is actually expanded polystyrene foam or EPS. This material is made from polystyrene, a plastic that’s often used to make clear products like food packaging or lab equipment. When polystyrene is combined with colorants, additives or other plastics, it can be utilized in the creation of toys, car parts, appliances and much more.

EPS is made up of mostly air — around 95% in fact. Over the years, EPS has become a go-to in the creation of insulated products like coffee cups and coolers. And because it’s so light, it’s used for products that float like rafts and life jackets, and it’s often used in shipping to cushion products.

So, If It's Not Styrofoam, What Is It?

While the claims that EPS is not biodegradable are true, this doesn’t mean that it can’t be recycled. EPS foam packaging can be extruded back into solid polystyrene pellets. These pellets can then be used to make items like coat hangers, picture frames, foodservice packaging and more.

If you need EPS foam recycling equipment, Foam Equipment and Consulting can help. We are a proud supplier of Heger foam recycling equipment and can help you find an EPS recycling compactor or grinding equipment that meets your company’s needs.