(315e) Characterization of Linear Low-Density Polyethylene (LLDPE) and Maleated Linear Low-Density Polyethylene (LLDPE-g-MA) Infused with Nanoclay in Supercritical Carbon Dioxide

Nanoclay fillers have the ability to enhance the thermo-mechanical, barrier and flame resistant properties of Linear Low-Density Polyethylene (LLDPE). Although the difficulties with the use of nanoclay fillers lie in the completeness of exfoliation and also in the extent of dispersion into a polymer matrix in order to achieve a maximum level of property enhancement. One method employed to successfully disperse powders into polymers that is both inexpensive and deemed environmentally friendly is supercritical carbon dioxide processing. With supercritical carbon dioxide processing, Cloisite 93A was infused into LLDPE and Maleated LLDPE (LLDPE-g-MA). Upon a visual inspection, clay infusion was achieved near the surface of the polymer pellet, but no clay found its way to the interior of the pellet. And the combination of FTIR and XRD analysis suggests that a high degree of exfoliation was achieved for select runs. This work describes a method to determine the amount of nanoclay infused into a polymer via FTIR analysis. Using this method, the percentage of Cloisite 93A infused into LLDPE and LLDPE-g-MA was determined. Along with dispersion, supercritical carbon dioxide has been used to exfoliate nanoclays, lending to the possibility of the combination of exfoliation and dispersion into a single step.