Doctor of Philosophy (PhD)
The overall objective of the research presented here is to understand the nanoscopic and microscopic structures that exist in dispersions of laponite and montmorillonite in poly(ethylene oxide), (PEO) and to correlate their shear responses with the final structure and properties of multilayered nanocomposite films prepared from these dispersions. These structures were examined as a function of polymer molecular weight, polymer and clay concentrations, and type of clay used to prepare the nanocomposites. A sequence of shear and elongational rheological measurements is used to provide a more complete physical picture on the structure of polymer-clay hydrogels, while a combination of techniques such microscopy (SEM, AFM, PLOM), XRD, DSC, TGA, DMA is used to study the structure and thermo-mechanical properties of the multilayered nanocomposite films. It was found that polymer molecular weight, polymer and clay concentrations, and the aspect-ratio of clay platelets strongly influence the rheology of nanocomposite dispersions as well as crystallinity, toughness and thermal properties of solid nanocomposite films prepared from such dispersions.
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Stefanescu, Eduard Adrian, "A Study of Rheological and Thermodynamic Properties of Polymer-Clay Gels and Multilayered Films" (2008). LSU Doctoral Dissertations. 2026.
William H. Daly