(694b) Effect of Supercritical Co2 on Morphology and Rheology of Polymer Nanocomposites Prepared by Melt Compounding

Well dispersion or intercalation/exfoliation of nanoscale fillers (such as nano-CaCO3 and nano-clay) in polymer matrix is currently not easy to be achieved. Supercritical carbon dioxide (ScCO2) has been reported to have great potential for facilitating the dispersion or intercalation/exfoliation of the nanoscale fillers in polymer matrix. So, in this paper, the effects of dissolved ScCO2 on the morphology of nano-CaCO3 and nano-clay were investigated in the polymer nanocomposites prepared using a twin-screw extruder. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the morphology of extruded nanocomposites. The dynamic rheological properties were measured using a dynamic rheometer in the oscillatory mode. Compared to the nanocomposites prepared without the aid of ScCO2, the nanocomposites with ScCO2 addition appear to have higher degree of nano-filler dispersion or intercalation/exfoliation.