Polyester fiber production using virgin and recycled PET

In this study, the design and construction of an extrusion equipment with spinning fiber devices has been developed to produce polyester fiber from virgin and recycled polyethylene terephthalate (PET). Several operating parameters (i.e., pressure, temperature, feed flow rate, extrusion speed and extruder design) have been analyzed to identify the best process conditions. In particular, this study has focused on a detailed analysis for the processing of recycled raw material for polyester textile fiber applications considering the variability of the process and identifying alternatives to minimize the impact on the quality parameters such as the fiber diameter and mechanical specifications. The experimental results were compared with the values calculated using a theoretical model, which has been developed for these particular cases. The mathematical analysis of the mass flow showed a very good agreement with respect to the experimental data, where there was a percentage difference < 3 %. It was found that the fiber diameter is a function of intrinsic viscosity (VI) or melt flow index (MFI). Finally, the mechanical properties of the fibers were evaluated and results indicated that the fiber with higher average molecular weight showed higher tenacity and lower Young’s modulus values.