Engineering Commons^™

Effect Of Graphitic Carbon Nanomodifiers On The Electromagnetic Shielding Effectiveness Of Linear Low Density Polyethylene Nanocomposites, Byron Villacorta Hernandez

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Conductive polymer composites have become alternative materials for providing electromagnetic and electrostatic shielding where metals are not suitable. In this study, the effect of crystallinity, morphology, concentration and orientation of carbon nanomodifiers on shielding provided by their polyethylene-based composites has been investigated relative to their transport properties.

First, the electrical properties and EM SE of composites consisting of heat-treated carbon nanofibers (Pyrograf^® -III PR-19 CNF) in a linear low density polyethylene (LLDPE) matrix were assessed. Heat treatment (HT) of CNF at 2500°C significantly improved their graphitic crystallinity and intrinsic transport properties, thereby increasing the EM SE of the nanocomposites. …

Phonon Transport Analysis Of Semiconductor Nanocomposites Using Monte Carlo Simulations, Mayank Malladi

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Nanocomposites are composite materials which incorporate nanosized particles, platelets or fibers. The addition of nanosized phases into the bulk matrix can lead to significantly different material properties compared to their macrocomposite counterparts. For nanocomposites, thermal conductivity is one of the most important physical properties. Manipulation and control of thermal conductivity in nanocomposites have impacted a variety of applications. In particular, it has been shown that the phonon thermal conductivity can be reduced significantly in nanocomposites due to the increase in phonon interface scattering while the electrical conductivity can be maintained. This extraordinary property of nanocomposites has been used to enhance …

Advanced Biomaterials From Renewable Resources: An Investigation On Cellulose Nanocrystal Composites And Co2 Extraction Of Rendered Materials, Jose Orellana

All Dissertations

The annual global consumption of petroleum-based plastics is approximately 280 million tons and is impacting the sustainability of our planet and prosperity of future generations. One solution is the development of bio-based polymer materials with advanced properties for commercial applications. Therefore, the ultimate goal of this dissertation is to investigate the properties of new bio-based materials for broader applications. This dissertation includes two research areas: cellulose nanocomposites, and CO₂ extractions of rendered fat. In the first half, cellulose nanocrystals (CNCs), which exhibit excellent mechanical and optical properties, were investigated for the reinforcement of a biodegradable polymer. The properties of …