Gradus

Recycled PET is already used in production, but only in small amount. Our final aim is to increase the regrind percentage in injection molded products. This research is focused on the characterization of original and regrind PET materials. Inherent viscosities were determined to characterize the materials. Flow curves of pure and regrind materials were measured at different temperatures. It was determined that the viscosity of the recycled material is lower than the value of the original material at each temperature. The molecules of the recycled material were supposed to shorten during the grinding process. If the temperature increases the shear viscosity decreases, but there was no linear correlation between these results. The structure viscous behavior of the polymer melt was revealed, while the viscosity decreases with increasing shear rate.

Keywords: PET, regrind, oscillation rheology, capillary viscosity, recycling,