Physical Sciences and Mathematics Commons^™

Polymer Nanocomposites Containing High Aspect Ratio Particulates: Innovation In Co-Extruded Multilayer Barrier Films, Kevin Meyers

Dissertations

Delaminated montmorillonite (MMT) clay/ maleic anhydride grafted LLDPE nanocomposite multilayer films with alternating layers of LDPE were produced through multilayer co-extrusion. The MMT concentration within the nanocomposite layers was increased through annealing the films in the melt due to a mismatch in interdiffusion rates of the polymer layers. Analysis of the nanocomposite layers upon annealing revealed that the platelets impinged upon one another resulting in significant improvement in oxygen barrier in the multilayer system, exceeding the results of bulk nanocomposites.

Model analysis demonstrated that increasing the nanoplatelet aspect ratio or initial concentration in the filled layers would lead to even …

Nanoparticle Filled Polymeric Systems For Gas Barrier And Flame Retardant Properties, Yingji Wu

Dissertations

Polymer composite gas barrier and fire retardant properties were studied in this investigation. An increase in the gas barrier property was observed by adding silicate nanotubes or clay nanoparticles into polymeric systems. Oxygen permeability, diffusivity, solubility and water vapor permeability were determined for polyimide/silicate nanocomposites with 0 to 9.99% (vol/vol) filler loading. Both oxygen and water vapor permeability for the system gradually decreased when adding increasing amounts of nanofiller up to 4.50% (vol/vol) and increase again after that. The permeability decrease was caused by both the diffusivity and solubility coefficient changes, although diffusivity (the tortuous factor) is the main reason …