Heated Assembly And Transfer Of Van Der Waals Heterostructures With Common Nail Polish,
2021
University of Nevada, Las Vegas
Heated Assembly And Transfer Of Van Der Waals Heterostructures With Common Nail Polish, Kristine L. Haley, Jeffrey A. Cloninger, Kayla Cerminara, Randy M. Sterbentz, Takashi Taniguchi, Kenju Watanabe, Joshua O. Island
Physics & Astronomy Faculty Research
Recent advances in the manipulation and control of layered, two-dimensional materials has given way to the construction of heterostructures with new functionality and unprecedented electronic properties. In this study, we present a simple technique to assemble and transfer van der Waals heterostructures using common nail polish. Commercially available nail polish acts as a resilient sticky polymer, allowing for the fabrication of complex multi-material stacks without noticeable fatigue. Directly comparing four commercially available brands of nail polish, we find that one stands out in terms of stability and stacking characteristics. Using this method, we fabricate two top-gated devices and report their …
Analysis Of The Use Of Waste Material In 3d Printing,
2021
California Polytechnic State University, San Luis Obispo
Analysis Of The Use Of Waste Material In 3d Printing, Alexander Laurence
Materials Engineering
Globally, only 9% of plastic by mass is recycled. Allowing consumers to directly convert polyethylene terephthalate (PET) waste into 3D filament can increase the recycling rate by reducing contamination and costs from traditional large-scale recycling methods. This was tested by heating strips of PET to various temperatures within its glass transition region and pressing a roller with a 1.75 mm indentation against it to observe strip deformation. PET was also placed in a hemispherical well with a 1.75 mm diameter hole at the bottom and heated above its melting temperature to determine the mass of PET required to extrude 3D …
Void And Density Analysis Of Cyanate Ester Composites,
2021
California Polytechnic State University, San Luis Obispo
Void And Density Analysis Of Cyanate Ester Composites, Cameron B. Atwood
Materials Engineering
In large scale composite manufacturing, voids and their frequency within prepreg materials play an important role in predicting the mechanical properties of a final composite laminate. The industry standard process for determining voids in composite materials is through resin digestion and resin ignition via ASTM D3171. One limitation to this standard is its ability to frequently produce negative void volume values in quality control testing, due to the calculation sensitivity of input resin and fiber densities. For this reason, Toray Advanced Composites wanted to investigate the process steps of ASTM D3171 to determine if discrepancies in resin density data may …
Uv Polymerization Of A Zwitterionic Antifouling Membrane Coating,
2021
California Polytechnic State University, San Luis Obispo
Uv Polymerization Of A Zwitterionic Antifouling Membrane Coating, Amanda Jia-Hwa Tsai, Vincent Matthew Guarino
Materials Engineering
Membrane filtration is used in a wide array of industries to separate components in a mixture. Filtration membranes suffer from the external deposition of pollutants and microorganisms, a phenomenon known as fouling. Fouling reduces the lifetime of a membrane and therefore increases production costs. The goal of this project was to modify the surface of a hydrophobic commercial membrane with a charged coating to induce antifouling properties. A zwitterionic monomer, sulfobetaine methacrylate (SBMA), was used for its steric hindrance and hydration shell formation mechanisms, which result in superior non-specific antifouling performance. When polymerizing the coating onto the surface of the …
Effects Of Uv Exposure On The Thermo-Mechanical Properties Of Cactus Based Biopolymers,
2021
California Polytechnic State University, San Luis Obispo
Effects Of Uv Exposure On The Thermo-Mechanical Properties Of Cactus Based Biopolymers, Madison Glozer, Megan Bolling, Addison Wolfson
Materials Engineering
The viability of renewable biopolymers as sustainable alternatives to synthetic plastics is promising, however ultra-violet (UV) radiation can lead to premature degradation and reduction in the material’s performance. Biopolymers comprised of nopal cactus juice, animal protein, natural wax, and glycerin in differing percentages were studied to obtain thermo-mechanical data in relation to UV exposure. To quantify degradation, dynamic mechanical analysis, thermogravimetric analysis, differential scanning calorimetry, infrared spectroscopy, goniometry and gravimetric measurements were performed. Each formulation experienced mass loss as a result of UV exposure, which could be attributed to water evaporation. The thermogravimetric analysis indicated a reduction in the second …
The Effects Of Glass Fiber Fillers On Epoxy Resin Performance,
2021
California Polytechnic State University, San Luis Obispo
The Effects Of Glass Fiber Fillers On Epoxy Resin Performance, Ashton Robert Reinhold, Manuel Jose Aguirre Ii
Materials Engineering
Premature failure of filtration members in biochemical processing is a costly issue for manufacturers. This research aims to determine whether or not the premature failure due to thermal fatigue in medical filtration devices can be mitigated by glass fiber addition. The study was conducted to identify the effects of e-glass fiber filler content in an epoxy matrix on the mechanical and thermal properties of the epoxy system. The epoxy was evaluated over a filler content of 0-50wt% in level increments of 12.5wt% and temperatures ranging from ambient to 160°C in increments of 15°C. Cylindrical and tensile bar specimens were prepared …
Solvent Analysis Of Phenolic Resin Glass Fiber Reinforced Prepreg During Out-Time,
2021
California Polytechnic State University, San Luis Obispo
Solvent Analysis Of Phenolic Resin Glass Fiber Reinforced Prepreg During Out-Time, Sixin Zhai, Crystal Ipong
Materials Engineering
Phenolic resin glass fiber reinforced prepregs are highly suitable for airplane interior components due to their high fire resistance, high temperature performance, and low-density characteristics. Safran Cabin seeks to improve their storage of the phenolic resin prepreg during their manufacturing process. The issues the company faces are the occasional delamination of prepreg laminas or the loss of tackiness rendering the lamina unfit for use. The area of investigation was determining the weight loss of volatiles during out-time. The term “out-time” consists of the time the prepreg experiences in transit, on the shop floor, and in short-term temperature-controlled storage. Simulated storage …
Reducing The Fouling Of Microfiltration Membranes Through Uv-Initiated Surface Modifications Using Poly (Ethylene Glycol) Based Monomers,
2021
California Polytechnic State University, San Luis Obispo
Reducing The Fouling Of Microfiltration Membranes Through Uv-Initiated Surface Modifications Using Poly (Ethylene Glycol) Based Monomers, Christopher Lo, Matthew Truong
Materials Engineering
Meissner Filtration Product Inc. designs and manufactures membranes for food and beverage, microelectronics, ultrapure chemicals, and pharmaceutical industries. Membrane filters utilized in these industries have lifetimes greatly limited due to membrane fouling. Increasing membrane lifetime will reduce downtime, waste, and cost of operation. The proposed project is aimed to develop a methodology for synthesizing a fouling-resistant polymer coating layer on hydrophobic membrane surfaces for reducing membrane fouling and increasing membrane filterability (membrane lifetime) that are critical for effective membrane operations in the pharmaceutical industry. In this study, commercial membranes were coated with a solution containing a monomer, crosslinker, and photoinitiator …
Development Of A Marine Biodegradable Target Balloon,
2021
California Polytechnic State University, San Luis Obispo
Development Of A Marine Biodegradable Target Balloon, Blake Samuel Robinson, Arash Sam Akhavi, David Leonardo Albarran-Martinez
Materials Engineering
The US Navy utilizes PVC target balloons, known as Killer Tomatoes, that are inflated onboard a naval vessel then deployed into the ocean to calibrate a variety of weaponry. The Navy has requested the investigation of biodegradable polymers to replace the PVC in attempts to reduce ocean waste that is generated from the leftover PVC material. After communicating with American Pacific Plastic Fabricators (APPF), the current manufacturer of the Killer Tomatoes, we gained an understanding of the manufacturing process and the material requirements that would allow a new material to be integrated into their current process. Two proprietary, trial polymers …
Pressure Driven Desalination Membranes: Lyotropic Liquid Crystals Containing Single Walled Carbon,
2021
California Polytechnic State University, San Luis Obispo
Pressure Driven Desalination Membranes: Lyotropic Liquid Crystals Containing Single Walled Carbon, Matteo A. Del Giudice, Samantha Castillo Merigold
Materials Engineering
This project presents a potential alternative desalination technique that utilizes the ion rejection properties of single walled carbon nanotubes dispersed in a lyotropic liquid crystal (LLC) matrix. Previous research has pointed to the polymerizable surfactant methacryloxy ethyl hexadecyl dimethyl ammonium bromide (C16MA) having capabilities of filtering molecular components smaller than a nanometer, when oriented in cylindrical micelles. SWCNTs were dispersed in deionized water by probe sonication and addition of surfactant cetyltrimethylammonium bromide (CTAB) due to SWCNTs’ hydrophobic properties. Membranes were produced containing 55wt% C16MA, 37wt% DI water, 0.1wt% with respect to the monomer (WRM) SWCNTs, 1.9 wt% WRM 2,2-dimethoxy-2-phenylacetophenone (photointiator), …
Composition For Protecting Technological Equipment Against Salt Deposits And Internal Corrosion,
2021
Tashkent Chemical-Technological Institute, Tashkent, Uzbekistan
Composition For Protecting Technological Equipment Against Salt Deposits And Internal Corrosion, Hasan Kadirov, Sadritdin Turabdjanov
CHEMISTRY AND CHEMICAL ENGINEERING
Aimed studies on the synthesis of metal complexonates have carried out. The reaction of obtaining zincate zincate oxyethylene diphosphonic acid OEDP has studied. On the basis of synthesized zincate-OEDP, compositions of corrosion inhibitors and deposits of mineral salts with the addition of a vacuum residue of monoethanolamine (RMEA) and polyaminocrotanol (PKI-3), which are able to effectively suppress corrosion processes in environments with different initial corrosive activity, have been compiled. It is proved that the high efficiency of the composition OEDP : zincate-OEDP : PKI-3 (maximum protective effect - 97.9%) is much more effective than the composition OEDP : zincate-OEDP : …
Rational Disposal Of Pet Containing Waste And Prospects For The Synthesis Of New Polymers,
2021
Tashkent Chemical-Technological Institute, Tashkent, Uzbekistan
Rational Disposal Of Pet Containing Waste And Prospects For The Synthesis Of New Polymers, Asror Juraev, Muzaffar Alimukhamedov, Ravshan Adilov, Farhod Magrupov
CHEMISTRY AND CHEMICAL ENGINEERING
As a result of the research on the utilization of polyethylene terephthalate-containing household waste, a promising direction was identified in the production of a new type of secondary polyethylene terephthalate (SPET) - unsaturated polyesters.It was revealed that the final product, which formed when the alcoholization process is complete in any proportion of of glycol and secondary polyethylene terephthalate, is the bisalkylent terephthalate of terephthalic acid; the content of the alcoholysis product consists of bisalkylent terephthalate, different molecule mass, functionally hydroxyl-containing complex polyester polyol and free diols.
The laws of alcoholization of secondary …
Rehology And Electrical Conductivity Of Particulate Composites In Additive Manufacturing,
2021
Southern Methodist University
Rehology And Electrical Conductivity Of Particulate Composites In Additive Manufacturing, Bin Xia
Mechanical Engineering Research Theses and Dissertations
Extrusion-based multi-functional additive manufacturing (AM) has been a rapidly developing area in AM recently. Particulate composites are widely used in this area to provide different functionalities with different types of particulate additives. However, there is no systematic understanding of the behavior of particulate composites during extrusion (especially in small nozzles) or of their properties once deposited in the build. This work investigates the properties of the type of particulate composites usually used in additive manufacturing, composed of a polymer matrix material and particulate additives within the micrometer scale. The focus is on the material rheology in the nozzle/capillary (for the …
Atomic Oxygen Resistant Low Earth Orbit Stable Polymer Matrix Composites Employing Phenylphosphine Oxide Epoxy-Amines,
2021
The University of Southern Mississippi
Atomic Oxygen Resistant Low Earth Orbit Stable Polymer Matrix Composites Employing Phenylphosphine Oxide Epoxy-Amines, Witold Fuchs
Dissertations
Atomic oxygen (AO) attacks polymer matrix composites (PMC’s) on the surfaces of spacecraft in low earth orbit (LEO) and threatens safe spacecraft operation and service life. Incorporating phenylphosphine oxide (PPO) groups into polymer chains offers a self-regenerating method of protection from AO but remains poorly understood. Herein, epoxies containing PPO groups were synthesized with increasing concentrations of phosphorus [P] from 0 to 8 wt % to investigate their AO resistance. Measurements confirmed the exposure of these materials to AO produces a passivation phosphate (POx) layer on the surface of the sample and the efficacy of the resultant layer was directly …
Characterization Of Gesn Semiconductors For Optoelectronic Devices,
2021
University of Arkansas, Fayetteville
Characterization Of Gesn Semiconductors For Optoelectronic Devices, Hryhorii Stanchu
Graduate Theses and Dissertations
Germanium-tin alloys with Sn compositions higher than 8 at. % to 10 at. % have recently attracted significant interest as a group IV semiconductor that is ideal for active photonics on a Si substrate. The interest is due to the fact that while at a few percent of Sn, GeSn is an indirect bandgap semiconductor, at about 8 to 10 at. % Sn, GeSn transitions to a direct bandgap semiconductor. This is at first surprising since the solid solubility of Sn in Ge under equilibrium growth conditions is limited to only about 1 at. %. However, under non-equilibrium growth conditions, …
Utilizing The Oxygen-Barrier Properties Of Poly(Isobutylene) To Enhance Photon Upconversion In Thermoplastic Elastomers,
2021
The University of Southern Mississippi
Utilizing The Oxygen-Barrier Properties Of Poly(Isobutylene) To Enhance Photon Upconversion In Thermoplastic Elastomers, Haley Carroll
Honors Theses
Upconversion (UC) is the conversion of low energy light to higher energy light. It is utilized for a broad range of applications such as solar energy harvesting, microscopy of cellular biology, and cancer therapy. Specifically, triplet-triplet annihilation UC (TTA-UC) involves two dye species, a sensitizer and an annihilator, which are capable of upconverting noncoherent light such as sunlight. Traditionally, TTA-UC is achieved in solution, rubbers, or glasses, however, this work probes the capabilities of a thermoplastic elastomer (TPE) matrix to examine the effect of phase-separated morphology on the energy transfers necessary for TTA-UC. The system herein consists of poly(styrene-isobutylene-styrene) (SIBstar) …
Effects Of Static Mixer Geometry On Polyurethane Properties,
2021
The University of Southern Mississippi
Effects Of Static Mixer Geometry On Polyurethane Properties, Christian R. Dixon
Honors Theses
The field of additive manufacturing has gained significant academic interest in the past few decades with a recently developed type of three-dimensional (3D) printing. Reactive extrusion additive manufacturing combines precursor materials within a static mixer (SM) head, where polymerization begins before deposition. Variable static mixer geometries currently exist, but the relationship between mixer geometry and post-polymerization mechanical properties is undefined. To elucidate this relationship, a series of experiments with identical chemistry was performed using a high shear SM, a low shear SM, and a comparative batch reaction. While higher shear mixing trends with faster polymerization for step-growth polymerizations, consistent precursor …
Biopolymeric Materials For Tissue Regeneration, Cell Manufacturing, And Drug Delivery,
2021
University of Arkansas, Fayetteville
Biopolymeric Materials For Tissue Regeneration, Cell Manufacturing, And Drug Delivery, David Alfonso Castilla-Casadiego
Graduate Theses and Dissertations
The development of materials for tissue regeneration, cell manufacturing, and drug delivery is possible by the manipulation of polymer properties and the use of three different techniques including layer-by-layer, electrospinning, and molding technique.
By applying the layer-by-layer technique over biomaterials, it is possible to develop polymeric multilayers that promote a more favorable environment for cellular functionality, increasing the possibility of improving their acceptance in the area of implantation. IRVASE demonstrated being a powerful technique that allows for a reliable characterization of the physical-chemical and thermal properties of the fabricated surfaces. This opens the possibility to monitor the design of surfaces …
Development Of Biomaterials For Drug Delivery,
2021
University of Arkansas, Fayetteville
Development Of Biomaterials For Drug Delivery, Raquel De Castro
Graduate Theses and Dissertations
Drug delivery systems (DDS) have highly evolved in the last decades with the development of hydrogels and nanoparticles. However, high systemic uptake, side effects, low bioavailability, and encapsulation efficiency continue to be a major hurdle faced by such DDSs.
Nanoparticles and hydrogels can be specifically designed for targeted DDSs to mitigate some of the problems. This dissertation aimed to design two DDSs for ocular drug delivery and one for cancer treatment. The first project sought to develop chitosan nanoparticles (Cs-NP) using PEGDA as a copolymer to encapsulate gentamicin (GtS) for ocular drug delivery. Cs-NPs contain positive charges that can interact …
Oxone® Mediated Tempo-Oxidized Cellulose Nanomaterials: Material Characterization, Ultrafiltration Membrane Separations, And Thin Film Composite Gas Transport Analysis,
2021
University of Arkansas, Fayetteville
Oxone® Mediated Tempo-Oxidized Cellulose Nanomaterials: Material Characterization, Ultrafiltration Membrane Separations, And Thin Film Composite Gas Transport Analysis, John Phillips Moore
Graduate Theses and Dissertations
Cellulose nanomaterials (CNMs) are derived from plant matter and are comprised of nanoscopic cellulose crystals and fibers. They have a diverse set of applications, from cosmetics to oil recovery. This study focuses on the properties of Oxone® mediated TEMPO-oxidized cellulose nanomaterials (OTO-CNMs) and their use in controlling the transport properties of polymeric substrates. Synthesis and characterization of cellulosic nanoparticles have resulted in the creation of OTO-CNMs with properties that increase hydrophilicity. With added hydrophilicity, OTO-CNMs possess lower fouling propensity, making them ideal membrane additive for transport limited separations such as hemodialysis.
To utilize the material and unique properties thereof, this …
