What is PE (Polyethylene)?

What is PE (Polyethylene)? Polyethylene (PE) is a thermoplastic polymer from the polyolefin group and, along with polypropylene (PP) and polyethylene terephthalate (PET), is one of the most widely used packaging materials worldwide. It is produced by the polymerization of ethylene and is characterized by high toughness, chemical resistance, and impact strength.

There are different types of polyethylene that vary in density and molecular structure: LDPE (Low Density Polyethylene): Soft, flexible, and highly stretchable. With a density of about 0.91–0.93 g/cm³, it is commonly used for films, bags, and flexible lids. HDPE (High Density Polyethylene): Harder, stiffer, and more dimensionally stable than LDPE. With a density of 0.94–0.97 g/cm³, it is ideal for rigid packaging such as cans, bottles, or pails. PE is impermeable to water, odorless, and physiologically safe, making it highly suitable for food packaging.

It is resistant to most acids, alkalis, alcohols, and aqueous salt solutions, but sensitive to strong oxidizing agents (e.g. nitric acid). The typical service temperature range is around –50 °C to +80 °C, with HDPE offering slightly higher heat resistance due to its density.

PE is fully recyclable (recycling code 02 for HDPE, 04 for LDPE) and can be tailored to specific applications through additives or coextrusion.