Estudio de los efectos producidos por las condiciones de transformación en la viscosidad del Polietilentereftalato (PET) reciclado.

Abstract

The effect produced by the processing conditions on the viscosity of recycled polyethylene terephthalate was studied. For this, a simulation of the processing was carried out using a melt flow index plastometer, based on a factorial design of experiments 22. The temperature and the retention time of the polymer inside the processing chamber were selected as independent factors, while the intrinsic viscosity of the polyethylene terephtalate was the response variable. Through a linear regression analysis of the experimental design, it was possible to obtain for the first time the equation of the model adjusted for intrinsic viscosity, on which the two factors studied (time and temperature) as well as the interaction between them presented a significant effect with a level 95% confidence. In all cases, there was a decrease in the viscosity of the recycled polyethylene terephthalate, with the highest incidence being 30% when the temperature increased from 260 to 280 °C. For a recycling process, it is recommended to maintain a temperature profile that does not exceed 260 °C and residence times equal to or less than 10 min.