(163aq) The Enhanced Barrier Effects and Thermal Properties of Polymer/Alumina Nanocomposites Fabricated by Atomic Layer Deposition

Using Atomic Layer Deposition (ALD), micron-sized polymer particles, such as High Density Polyethylene (HDPE) and Poly Lactic Acid (PLA) were coated with nanoscale alumina (Al2O3) films in a Fluidized Bed Reactor (FBR). The coated polymer particles were extruded to form polymer/alumina nanocomposite film. The homogeneous dispersion of the alumina shells in the polymer matrix following extrusion was confirmed using cross section Transmission Electron Microscopy (TEM) and Energy Dispersive Spectroscopy (EDS). The barrier effect of the composite film was investigated. The alumina shells dispersed in the polymer matrix can reduce gas permeability and increase the lag time in polymer films. The thermal behavior of the composites was evaluated by Thermal Gravimetric Analyzer (TGA) and the results showed that the inclusion of nanoscale alumina shells can improve the thermal stability of polymer.