Properties of clay nanocomposites based on petg by twin-screw extruder using supercritical CO₂

A twin-screw extrusion process for PETg/clay nanocomposites using supercritical carbon dioxide was studied. Well-dispersed nanocomposites enhance the superior properties of the PETg/clay nanocomposites. So, we studied to achieve a good dispersion of the individual silicate layers of the clay. For even more enhancement of the dispersion of the clay in polymeric phase, supercritical CO₂ can be employed in the processing of the nanocomposites due to the fast diffusion into the clay particles. The properties of PETg/clay nanocomposites are investigated by rheometer, thermal analyzer, permeability tester, and mechanical tester. The effects of clay contents and CO₂ feed rate on the rheological and barrier properties of PETg/clay nanocomposites are presented. The results show that the rheological and thermal properties of the nanocomposites increase with the addition of clay. Moreover, the analysis of the nanocomposites also reveals that the use of supercritical CO₂ leads to an increase of the rheological and barrier properties. From the results above, we strongly suggest that the use of supercritical CO₂ assisted twin-screw extrusion is an effective way to improve the superior properties of PETg/clay nanocomposites.