The generic name for Styrofoam is expanded polystyrene foam (EPS). While widely recognized, Styrofoam is actually a registered trademark of The Dow Chemical Company, specifically referring to a brand of extruded polystyrene foam (XPS) typically used for building insulation. The white, rigid foam commonly used for disposable cups, packaging peanuts, and protective cushioning is the generic expanded polystyrene foam, or EPS.
Understanding Expanded Polystyrene Foam (EPS)
Expanded polystyrene foam, or EPS, is a lightweight, rigid, plastic foam material. It is a derivative of polystyrene, a synthetic aromatic polymer made from the monomer styrene. Polystyrene is a versatile plastic that can be found in various forms, often used to create clear products like food packaging, disposable cutlery, and lab equipment due to its clarity and rigidity.
The production of EPS involves heating polystyrene beads, which contain a blowing agent (usually pentane). This process causes the beads to expand, forming small, closed-cell foam spheres. These expanded beads are then molded together under heat and pressure to create blocks or sheets of foam, or custom-shaped products.
Why the Confusion?
The term "Styrofoam" has become a genericized trademark, much like "Kleenex" for facial tissues or "Band-Aid" for adhesive bandages. This widespread adoption of the brand name for the general product often leads to confusion about the actual material's generic identity.
| Aspect | Brand Name | Generic Material |
|---|---|---|
| Name | Styrofoam | Expanded Polystyrene Foam (EPS) |
| Manufacturer | The Dow Chemical Company | Various manufacturers |
| Primary Use | Building insulation (typically blue or pink XPS foam) | Protective packaging, disposable food containers, insulation (typically white EPS foam) |
| Composition | Extruded Polystyrene (XPS) | Expanded Polystyrene (EPS) |
Common Applications of EPS
Due to its excellent insulation properties, lightweight nature, and shock absorption capabilities, expanded polystyrene foam (EPS) is utilized in a vast array of applications across various industries:
- Packaging: Widely used for protective packaging of electronics, appliances, and fragile items due to its ability to absorb impact and cushion products during transit.
- Food Service: Common for disposable coffee cups, takeout containers, and meat trays because of its insulating properties that keep food and beverages at desired temperatures.
- Construction: Employed as insulation for walls, roofs, and floors, as well as in geofoam blocks for civil engineering projects to reduce soil loads and fill voids.
- Crafts and Hobbies: Often found in sheets or blocks for sculpting, model-making, and various DIY projects.
- Buoyancy Aids: Used in life rafts, buoys, and other flotation devices due to its closed-cell structure, which makes it resistant to water absorption.
Understanding that Styrofoam is a specific brand of polystyrene foam, while expanded polystyrene foam (EPS) is the generic material, helps clarify the terminology around this ubiquitous and versatile plastic.
