New Extrusion Process Recycles Food-Grade PET

PTP Plastic Technologies and Products bv in Prague, Czech Republic, seeks to license a reactive extrusion process to upgrade clean post-consumer PET bottle flake into food-grade PET for new bottles or film. A 6-million-lb/yr plant is producing material for customer testing. Washed PET flakes are added to a mixer where they are coated with a liquid silicone-based additive. The flakes are fed to a twin-screw extruder where molecular weight is restored. PET-M (modified PET) is then pelletized and crystallized (using residual heat from pelletizing). PTP’s chemical-aided extrusion process is reportedly less expensive than solid-stating and achieves properties comparable to or better than virgin PET. Elongation at break is said to be 50% to 100% greater than virgin PET, and PET-M is hydrophobic instead of hydrophilic like normal PET, so it reportedly dries four times faster. PET-M has been certified acceptable for food contact. PTP will present the process for the first time at Nova-Pack Europe 2006, Oct. 2-3, in Prague, organized by Schotland Business Research, Skillman, N.J.