Preparation of recycled polyethylene terephthalate pellets, and bottles formed therefrom

Abstract

A method for recycling polyethylene terephthalate, including obtaining flakes of polyethylene terephthalate which are re-polymerized using heat and/or a chain extender combined with an anti-yellowing agent to yield an average molecular weight of at least 40,000 Da and a tunable intrinsic viscosity of approximately 0.5 dl/g to 0.8 dl/g. Polyethylene terephthalate pellets are produced having a color deviation of approximately 2.5 or less from the re-polymerized 100 percent post-consumer polyethylene terephthalate flakes as raw material for formation of polyethylene terephthalate products. When compared to available rPET bottles, CIELAB color values show indiscernible color differences with the high quality rPET produced. Consequently, the high-quality rPET pellets produced are capable manufacturing PET bottles with 100% PCR content and a high number of repeated recycling cycles.