PETschuimen

PETschuimen is a term used in polymer science to describe a microcellular foaming process applied to polyethylene terephthalate (PET). The name combines PET with the German verb schäumen, meaning to foam, reflecting the creation of cellular PET structures during processing. PETschuimen refers both to the concept of PET foaming and to specific processing routes that generate closed-cell microfoam within PET specimens.

The method typically relies on introducing a blowing agent, such as supercritical or gaseous CO2, or a chemical blowing agent, during melt processing. The agent creates numerous small gas bubbles as the polymer cools, producing a lightweight, porous structure. Control of cell size, cell density, crystallinity, temperature, pressure, and residence time is essential to achieve uniform foaming and desired mechanical properties. Techniques include extrusion foaming, injection molding with microcellular tooling, and secondary processing to optimize cell distribution.

Properties of PETschuimen foams include reduced density and improved energy absorption, while maintaining a significant portion of PET’s stiffness and clarity in some formulations. They offer potential advantages for packaging, protective cushioning, and automotive interior components due to weight reduction, insulation, and potential recyclability. However, achieving uniform cell structures can be challenging, and processing conditions must be tightly controlled to prevent defects such as cell collapse or voids. Compatibility with PET crystallization and downstream recycling are important considerations in industrial adoption.

In current practice, PETschuimen is a subject of ongoing research for scalable manufacturing, material performance optimization, and environmental assessment, with applications ranging from sustainable packaging to lightweight structural components.