Folienbarriere

Folienbarriere, or barrier film, refers to a polymer-based or composite film designed to limit the transmission of gases, moisture, aromas, or light in order to protect contents and extend shelf life. These films are common in packaging, but are also used in electronics and pharmaceuticals where protective barriers are required.

Barrier properties are achieved through multi-layer structures that combine materials with low permeability. Typical barrier materials include EVOH (ethylene vinyl alcohol) for oxygen resistance, PVDC, aluminum foil or metalized layers, and additional polymers such as PET, PA (nylon) or PP/PE for mechanical strength and sealability. Barrier films are usually produced as laminates or coextruded structures and may incorporate coatings or inorganic barriers to tailor performance for specific needs.

Production and design considerations involve extrusion, casting, lamination, or metallization, often with tie layers to join different materials. The design must balance barrier performance with other requirements such as mechanical strength, heat sealing, printability, and recyclability. Temperature and humidity exposure strongly influence barrier effectiveness, particularly for moisture-sensitive layers like EVOH.

Applications cover food packaging (coffee, snacks, ready meals), pharmaceuticals and medical devices, and electronics packaging. By reducing oxidation, moisture ingress, and flavor loss, barrier films help maintain quality and safety and can contribute to waste reduction.

Performance is quantified by measures such as oxygen transmission rate (OTR) and water vapor transmission rate (WVTR). Standard test methods include ASTM D3985 for O2 permeability and ASTM E96 or ISO 15105 for WVTR. Values depend on material choice, thickness, and conditions.

Environmental aspects include recyclability challenges due to multi-layer structures. Industry developments aim at mono-material barrier films or recyclable laminates, as well as improved sustainability across end-of-life pathways. See also barrier film, EVOH, PVDC, and metallized films.