This thesis analyzed Canon GPR-30 Black Standard Yield Toner in hopes to gain better understanding of the additives and plastic used in a popular photocopier toner formulation. By analyzing the toner’s composition from the perspective of its recyclability and potential to be manufactured using recycled plastic, this thesis hoped to fill a gap in current literature regarding how toner fits into a circular economy. While the analysis of the selected toner was ultimately inconclusive, three hypotheses about the toner’s composition are put forth based upon data from differential scanning calorimetry (DSC), solubility analysis, and Fourier Transform Infrared (FTIR) spectroscopy experimentation. It is hypothesized that the toner is most likely composed of either polymethyl methacrylate (PMMA) or polyethylene terephthalate (PET). Both of these polymers have characteristic FTIR peaks that were exhibited in the toner spectra and both polymers exhibit similar solubility behavior to toner samples. However, the glass transition temperature and melting temperature of the toner sampled were 58℃ and 74.5℃ respectively, both of which are much lower than that of PMMA and PET. Thus, a third hypothesis that would better support DSC findings is that the toner is primarily composed of nylon 6,6. While DSC data best matches this polymer, FTIR data seems to rule out nylon 6,6 as an option because its characteristic peaks were not found in experimental data. Thus, the Canon GPR-30 Black Standard Yield Toner is probably made from either PMMA or PET. Both PMMA and PET are 100% recyclable plastics which are commonly repurposed at recycling facilities, however, unknowns regarding toner additives make it difficult to determine how this toner would be recycled. If the printing industry hopes to move towards a circular economy in which plastic can be recycled to use towards toner manufacturing and toner can be “unprinted” from paper to be recycled into new toner, it is likely that monetary incentives or government regulations will need to be introduced to promote the sharing of toner formulations for recycling purposes.

Electrolytes play a critical role in electrochemical devices and applications, and therefore design and development of electrolytes with tailored properties are much desired to accommodate variety of operation requirements. Extreme temperatures are considered as one of the challenging environmental conditions, especially for devices rely on liquid state electrolytes, rendering failure of operations once the electrolyte systems undergo phase transitions. This work focuses on development of low-temperature iodide-containing liquid electrolyte systems, specifically designed for the molecular electronic transducer (MET) sensors in space applications. Utilizing ionic liquids, molecular liquids, and salts, multiple low-temperature liquid electrolytes were designed with enhancements in thermal, transport, and electrochemical properties. Effects of intermolecular interactions were further investigated, revealing correlations between optimization of microscopic dynamics and improvements of macroscopic characteristics. As a result, three low-temperature electrolyte systems were reported utilizing ethylammonium/water, gamma-butyrolactone/propylene carbonate, and butyronitrile as solvent with ionic liquid, 1-butyl-3-methylimidazolium iodide, and lithium iodide salt. Consequently, the liquidus range of these systems have been extended to -108 ˚C, -120 ˚C, and -152 ˚C, respectively, marking the lowest liquidus temperature of liquid electrolytes to the author’s best knowledge. Moreover, transport properties of designed systems were characterized from 25 to -75 ˚C. Effects of selected cosolvent/solvent on evolutions of transport properties were observed, revealing interplay between two governing mechanisms, ion disassociation and ion mobility, and their dominance at different temperatures. Experimental spectroscopy characterization techniques validated the hypothesized intermolecular interactions between solvent-cation and solvent-anion, complimented by computational simulation results on the complex dynamics between constituent ions and molecules. To support MET sensing technology, the essential iodide/triiodide redox were investigated in developed electrolytes. Effects of different molecular solvents on electrochemical kinetics were elucidated, and steady performances were validated under a properly controlled electrochemical window. Optimized electrolytes were tested in the MET sensor prototypes and showcased adequate functionality from calibration. The MET sensor prototype has also successfully detected real-time earthquake with low noise floor during long term testing at ASU seismology facility. The presented work demonstrates a facile design strategy for task-specific electrolyte development, which is anticipated to be further expanded to high temperatures for broader applications in the future.

Functional materials can be characterized as materials that have tunable properties and are attractive solutions to the improvement and optimization of processes that require specific physiochemical characteristics. Through tailoring and altering these materials, their characteristics can be fine-tuned for specific applications. Computational modeling proves to be a crucial methodology in the design and optimization of such materials. This dissertation encompasses the utilization of molecular dynamics simulations and quantum calculations in two fields of functional materials: electrolytes and semiconductors. Molecular dynamics (MD) simulations were performed on ionic liquid-based electrolyte systems to identify molecular interactions, structural changes, and transport properties that are often reflected in experimental results. The simulations aid in the development process of the electrolyte systems in terms of concentrations of the constituents and can be invoked as a complementary or predictive tool to laboratory experiments. The theme of this study stretches further to include computational studies of the reactivity of atomic layer deposition (ALD) precursors. Selected aminosilane-based precursors were chosen to undergo density functional theory (DFT) calculations to determine surface reactivity and viability in an industrial setting. The calculations were expanded to include the testing of a semi-empirical tight binding program to predict growth per cycle and precursor reactivity with a high surface coverage model. Overall, the implementation of computational methodologies and techniques within these applications improves materials design and process efficiency while streamlining the development of new functional materials.

Regolith excavation systems are the enabling technology that must be developed in order to implement many of the plans for in-situ resource utilization (ISRU) that have been developed in recent years to aid in creating a lasting human presence on the surface of the Moon, Mars, and other celestial bodies. The majority of proposed ISRU excavation systems are integrated onto a wheeled mobility system, however none yet have proposed the use of a screw-propelled vehicle, which has the potential to augment and enhance the capabilities of the excavation system. As a result, CASPER, a novel screw-propelled excavation rover is developed and analyzed to determine its effectiveness as a ISRU excavation system. The excavation rate, power, velocity, cost of transport, and a new parameter, excavation transport rate, are analyzed for various configurations of the vehicle through mobility and excavation tests performed in silica sand. The optimal configuration yielded a 28.4 kg/hr excavation rate and11.2 m/min traverse rate with an overall system mass of 3.4 kg and power draw of26.3 W. CASPER’s mobility and excavation performance results are compared to four notable proposed ISRU excavation systems of various types. The results indicate that this architecture shows promise as an ISRU excavator because it provides significant excavation capability with low mass and power requirements.

The way a granular material is transported and handled plays a huge part in the quality of final product and the overall efficiency of the manufacturing process. Currently, there is a gap in the understanding of the basic relationship between the fundamental variables of granular materials such as moisture content, particle shape and size. This can lead to flowability issues like arching and ratholing, which can lead to unexpected downtimes in the whole manufacturing process and considerable wastage of time, energy, and resources. This study specifically focuses on the development of a model based on the surface mean diameter and the moisture content to predict the flow metric flow function coefficient (FFC) to describe the nature of flow of the material. The investigation involved three parts. The first entailed the characterization of the test materials with respect to their physical properties - density, size, and shape distributions. In the second, flowability tests were conducted with the FT4 Powder Rheometer. Shear cell tests were utilized to calculate each test specimen's flow function parameters. Finally, the physical properties were correlated with the results from the flowability tests to develop a reliable model to predict the nature of flow of the test specimens. The model displayed an average error of -6.5%. Predicted values showed great correlation with values obtained from further shear cell tests on the FT4 Rheometer. Additionally, particle shape factors and other flowability descriptors like Carr Index and Hausner Ratio were also evaluated for the sample materials. All size ranges displayed a decreasing trend in the values of Carr Index, Hausner Ratio, and FFC with increasing moisture percentages except the 5-11 micron glass beads, which showed an increasing trend in FFC. The results from this investigation could be helpful in designing equipment for powder handling and avoiding potential flowability issues.

Rotary drums are tools used extensively in various prominent industries for their utility in heating and transporting particulate products. These processes are often inefficient and studies on heat transfer in rotary drums will reduce energy consumption as operating parameters are optimized. Research on this subject has been ongoing at ASU; however, the design of the rotary drum used in these studies is restrictive and experiments using radiation heat transfer have not been possible.<br/><br/>This study focuses on recounting the steps taken to upgrade the rotary drum setup and detailing the recommended procedure for experimental tests using radiant heat transfer upon completed construction of the new setup. To develop an improved rotary drum setup, flaws in the original design were analyzed and resolved. This process resulted in a redesigned drum heating system, an altered thinner drum, and a larger drum box. The recommended procedure for radiant heat transfer tests is focused on determining how particle size, drum fill level, and drum rotation rate impact the radiant heat transfer rate.

Energy return in footwear is associated with the damping behavior of midsole foams, which stems from the combination of cellular structure and polymeric material behavior. Recently, traditional ethyl vinyl acetate (EVA) foams have been replaced by BOOST(TM) foams, thereby reducing the energetic cost of running. These are bead foams made from expanded thermoplastic polyurethane (eTPU), which have a multi-scale structure consisting of fused porous beads, at the meso-scale, and thousands of small closed cells within the beads at the micro-scale. Existing predictive models coarsely describe the macroscopic behavior but do not take into account strain localizations and microstructural heterogeneities. Thus, enhancement in material performance and optimization requires a comprehensive understanding of the foam’s cellular structure at all length scales and its influence on mechanical response.

This dissertation focused on characterization and deformation behavior of eTPU bead foams with a unique graded cell structure at the micro and meso-scale. The evolution of the foam structure during compression was studied using a combination of in situ lab scale and synchrotron x-ray tomography using a four-dimensional (4D, deformation + time) approach. A digital volume correlation (DVC) method was developed to elucidate the role of cell structure on local deformation mechanisms. The overall mechanical response was also studied ex situ to probe the effect of cell size distribution on the force-deflection behavior. The radial variation in porosity and ligament thickness profoundly influenced the global mechanical behavior. The correlation of changes in void size and shape helped in identifying potentially weak regions in the microstructure. Strain maps showed the initiation of failure in cell structure and it was found to be influenced by the heterogeneities around the immediate neighbors in a cluster of voids. Poisson’s ratio evaluated from DVC was related to the microstructure of the bead foams. The 4D approach taken here provided an in depth and mechanistic understanding of the material behavior, both at the bead and plate levels, that will be invaluable in designing the next generation of high-performance footwear.

As experiencing hot months and thermal stresses is becoming more common, chemically protective fabrics must adapt and provide protections while reducing the heat stress to the body. These concerns affect first responders, warfighters, and workers regularly surrounded by hazardous chemical agents. While adapting traditional garments with cooling devices provides one route to mitigate this issue, these cooling methods add bulk, are time limited, and may not be applicable in locations without logistical support. Here I take inspiration from nature to guide the development of smart fabrics that have high breathability, but self-seal on exposure to target chemical(s), providing a better balance between cooling and protection.

Natural barrier materials were explored as a guide, focusing specifically on prickly pear cacti. These cacti have a natural waxy barrier that provides protection from dehydration and physically changes shape to modify surface wettability and water vapor transport. The results of this study provided a basis for a shape changing polymer to be used to respond directly to hazardous chemicals, swelling to contain the agent.

To create a stimuli responsive material, a novel superabsorbent polymer was synthesized, based on acrylamide chemistry. The polymer was tested for swelling properties in a wide range of organic liquids and found to highly swell in moderately polar organic liquids. To help predict swelling in untested liquids, the swelling of multiple test liquids were compared with their thermodynamic properties to observe trends. As the smart fabric needs to remain breathable to allow evaporative cooling, while retaining functionality when soaked with sweat, absorption of water, as well as that of an absorbing liquid in the presence of water were tested.

Micron sized particles of the developed polymer were deposited on a plastic mesh with pore size and open area similar to common clothing fabric to establish the proof of concept of using a breathable barrier to provide chemical protection. The polymer coated mesh showed minimal additional resistance to water vapor transport, relative to the mesh alone, but blocked more than 99% of a xylene aerosol from penetrating the barrier.