Polymer Chemistry Commons^™

Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, Agus Mulyadi Hasanudin, Eddy Sumarno Siradj

Journal of Materials Exploration and Findings

The production of metal and alloy products requires the use of heat treatment, when during the heat treatment process, quenching is a crucial step. The quenching medium can be anything from water, a salt bath, oil, air and gas. In a vacuum furnace, pressurized gas, most frequently nitrogen (N₂) gas, serves as one of the quenching mediums. One of the drawbacks of the quenching process is the distortion and dimensional change of the parts. This paper aims to investigate the influence of nitrogen gas quenching pressure on the distortion and dimensional change of aerospace actuator gear planet parts …

Optimization Of Transition-Metal Inclusive Carbon Aerogels For Electrochemical Energy Applications, Allen Dalton Davis

Electronic Theses & Dissertations

The ever-growing need for energy alongside rising concerns for climate change demands the development of renewable energy technologies. Hydrogen fuel cells are a promising technology that can serve to either supplement energy generation or act as a lone power source. Yet for these devices to be truly green, the hydrogen that serves as fuel must be procured from a renewable resource. Electrolytic water splitting is a process that allows for the dissociation of water into H₂ and O₂. For this process to be practical, the electrolyzer needs to demonstrate high efficiency and stability, as well as a …

Exploring Soybean Oil-Based Polyol And Effect Of Non-Halogenated Flame Retardants In Rigid Polyurethane Foam, Sahithi Kondaveeti

Electronic Theses & Dissertations

To address the increasing demand for sustainable biomaterials due to the depletion of fossil fuel resources and growing environmental concerns, a new type of biodegradable and environmentally friendly rigid polyurethane foam (RPUF) has been synthesized. These foams are derived from chemically modified soybean oil-based polyol obtained from soybean oil by epoxidation followed by a ring-opening reaction. Polyurethane foam is generally used in construction, furniture, and automobile industries but is highly flammable and releases toxic gases and smoke during combustion. In this study, a highly efficient synergistic effect halogen-free flame-retardant (FR) melamine salt, 2-carboxyethyl(phenyl)phosphinic acid melamine salt (CMA) was synthesized from …

Enhanced Mechanical Strength Of Soybean Oil-Based Non-Isocyanate Polyurethane Adhesive For Wood Application By Introducing Nanofillers, Vatsal Chaudhari

Electronic Theses & Dissertations

Polyurethane (PU) is a versatile material that finds extensive use in various industries including bedding, construction, automotive, and packaging. Historically, this particular polymer relied significantly on petrochemical resources, a practice that was considered to have negative environmental impacts. The conventional method for preparing PU involves the use of isocyanate, which is a disadvantage due to its negative impact on the environment and human health. The resolution of this problem entails identifying an appropriate substitute for petroleum-derived products that minimize their impact on both the environment and human health. The researchers earlier utilized soybean oil, for the formulation of PUs in …

Castor Oil Polyol-Based Adhesives With Additional Crosslinker For Improvement In Mechanical And Thermal Properties., Yash Desai

Electronic Theses & Dissertations

Polyurethanes (PU) have been promising polymeric materials with many applications, including adhesives. Projecting an estimated revenue from 42.8 billion $ in 2021 to 61.5 billion $ by 2026. However, a large number of PU adhesives are sourced from petroleum products. Therefore, to lower the dependence on non-renewable resources and provide sustainable and affordable alternatives. In this work will synthesize bio-based adhesives of polyurethane from modified castor oil-based polyol. Generally, polyurethane reaction depends on the properties of polyol and isocyanates. The most important aspect of these reactions is the OH number of the polyol, which is responsible for the crosslinking and …

High Temperature Materials From Bis-Ortho-Diynylarene (Boda)-Derived Resins And Perfluorocyclobutyl (Pfcb) Aryl Ether Polymers, Ernesto Isaac Borrego

Theses and Dissertations

This work expands the current understanding of materials chemistry and engineering capabilities of two synthetic platforms: 1.) bis-ortho-diynylarenes (BODA) and 2.) trifluorovinylaryl ethers (TFVE). Each platform possesses a unique chemistry which paradoxically enables the development of high-performance materials therefrom while simultaneously retaining exceptional melt and solution processability. Leveraging the apparent dichotomy in properties (performance/processability) obtainable from these two synthetics platforms, we have pursued and achieved a practical approach to high-temperature resistant materials with an immense potential for technology transfer and commercialization:

1.) BODA-derived resins (BDR) constitute a versatile platform of melt-processable resins capable of rapidly producing high performance …

Characterization Of Interlayer Laser Shock Peening During Fused Filament Fabrication Of Polylactic Acid (Pla), Fabien Denise

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

The field of additive manufacturing (AM) has gained a significant amount of popularity due to the increasing need for more sustainable manufacturing techniques and the adaptive development of complex product geometries. The problem is that AM parts routinely exhibit flaws or weaknesses that affect functionality or performance. Over the years, surface treatments have been developed to compensate certain flaws or weaknesses in manufactured products. Combining surface treatments with the modularity of additive manufacturing could lead to more adaptable and creative improvements of product functions in the future. The current work evaluates the feasibility of pursuing a new research axis in …

Solubility, Reactivity And Diffusion In Polymeric Bilayer Thin Films, Jacob Sitterly

Legacy Theses & Dissertations (2009 - 2024)

Microelectronics manufacturing of modern devices has required the use of polymer photoresists in several essential steps. The traditional limitation in device capability has been dependent on the minimum feature size attainable by the wavelength of light and materials used in photolithography. In this thesis the study of polymer thin films in single and bilayer stacks is described. Three scientific concepts are fundamental to this study: (1) the diffusion and (2) reaction of acid and small molecules that change polymer (3) solubility. In this thesis, two chemical systems are designed and used to study these three scientific concepts.

Upcyclying Of Polyethylene Terephtalate By Addition Of Thermoplastic Elastomer, Diego Francisco Bermudez

Open Access Theses & Dissertations

Continual overconsumption of single-use plastics has generated challenges of solid waste management across the United States. Common plastic waste management solutions, such as landfill, have caused the migration of contaminants into the environment consequently affecting not only the health of wildlife, but also that of human beings. Alternative strategies for the handling of single-use plastic such as polyethylene terephthalate (PET), used in the food packaging industry, can ultimately help mitigate the noxious consequences of single-use plastics affecting entire ecosystems. This study demonstrates a potential avenue of materials upcycling by studying the effects of coupling PET with the thermoplastic elastomer styrene-ethylene-butylene-styrene …

Nanoparticles And The Environment: Biopolymer Grafted Cellulose And Screen-Printed Carbon Nanotube Composites, Dominique Henry Porcincula

Master's Theses

A host of environmental issues will define the state of the environment in the 21^st century, with plastic pollution and water shortages among them. While solutions to these problems require large-scale, multipronged solutions, one way we can address them is through material innovation and the use of nanoparticles.

In the first project, we address the issue of plastic pollution by creating nanocomposites of biodegradable polymers (PLA and PCL) with cellulose nanofibrils. Here, PLA and PCL are grafted from the surface of cellulose nanofibrils via ring-opening polymerization of cyclic ester monomers. Polymer-grafted cellulose (PGC) is characterized with structural analysis, solubility …

Development Of Poly(Acrylamide)-Based Hydrogel Composites With Powdered Activated Carbon For Controlled Sorption Of Pfoa And Pfos In Aqueous Systems, Maria Victoria X. Klaus, Angela M. Gutierrez, J. Zach Hilt

UK CARES Faculty Publications

Per- and polyfluoroalkyl substances (PFAS) are anthropogenic compounds developed for various applications; some are connected to adverse health impacts including immunosuppression and higher susceptibility to some cancers. Current PFAS remediation treatments from aqueous sources include granular activated carbon (GAC) adsorption, membrane separation, and anion- exchange resin (AER) removal. Each has specific disadvantages, hence the need for a new and efficient technology. Herein, acrylamide-based hydrogel composites were synthesized with powdered activated carbon (PAC) and characterized to determine their affinity for PFAS. Physicochemical characterization included Fourier-Transform infrared spectroscopy (FTIR) to identify chemical composition, thermogravimetric analysis (TGA) to confirm PAC loading percentage, and …

Photocurable Ionized Vinylimidazole Liquid Salt For Antibacterial Application, Gina Park, Lisa Ahlberg, Robert Zdor

Celebration of Research and Creative Scholarship

There has been an increasing demand for antibacterial dental composite as it can prevent the biofilm formation and the adhesion of bacteria after the treatment causing the consequential cavities. Previous study explored the antibacterial activity of the heterogenous mixture of heterocyclic polymer and resin. It showed limitations as the mixture did not show antibacterial activity since the mixture could only contain a small amount of heterocyclic polymer within the resin due to its inconvenience of shaping and low miscibility. To overcome this limitation, this research focused on synthesizing heterocyclic antibacterial monomer liquid salt and curing it with UV light to …

Cationic Frontal Polymerization: Front Kinetics, Effects Of Additives, And Applications, Brecklyn R. Groce

LSU Doctoral Dissertations

Cationic frontal polymerization broadens the potential application of frontal polymerization by allowing for use of monomers such as epoxies and vinyl ethers. In this work, the effects of monomer and initiator composition and additives including fillers on front kinetics, along with applications of cationic frontal polymerization were investigated.

Using a radical-induced cationic frontal polymerization (RICFP) method with a superacid generating salt and a thermal radical initiator, the addition of vinyl ethers to epoxy formulations was studied, where an increase of front velocity was seen with increase of divinyl ether to epoxy ratio. Other aspects of vinyl ether systems, such as …

Synthesis And Characterization Of Polymer-Based Complex Nanomaterials, Prashun G. Roy

Dissertations, Theses, and Capstone Projects

The original research work in this dissertation is about the use of polymers in two significantly important areas. One involves creating mesoporous silica materials with various morphologies using a mixed Pluronic surfactant system made up of two poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) surfactants, one of which contains long hydrophilic (PEO) blocks and the other has a significantly higher proportion of hydrophobic PPO . In addition, a glucose responsive core-shell type microgel was also developed for shifting the glucose responsive volume phase transition by using polymeric nanomaterials.

Chapter 1 of the dissertation discussed some historical background of synthesis and uses of …

Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino

Biological Sciences Undergraduate Honors Theses

This honors thesis aims to investigate the reusability and performance of cell coatings for cell therapy applications. Cell therapy, which involves the use of human cells to repair or replace damaged tissues, holds immense potential for medical advancements. However, ensuring the survival and functionality of transplanted cells remains a significant challenge. We focused on studying the effectiveness of coatings applied to cells for improved cell growth and viability. The research project involved the preparation of the coatings using a layer-by-layer method and the subsequent seeding of cells. The coated cells were then subjected to a series of experiments to assess …

Atom Economical Reactions Of Terpenoids And Post-Consumer Plastics With Sulfur, Charini Maladeniya

All Dissertations

The production of Ordinary Portland Cement (OPC) and its uses have a complicated environmental impact, which is influenced by infrastructure development and building operations as well as CO₂ emissions, which account for 7% of all worldwide CO₂ emissions. Due to the increasing population, production is still ongoing. The search for cement and construction materials produced with zero to low CO₂ emissions is therefore continuous. Finding recyclable, CO₂ gas-free biocomposites with high sulfur content that can rival the mechanical properties of popular building supplies like Portland cement is the primary objective of the research discussed in this …

Composite And Polymer Formulation Employing Sulfur And Bio-Olefin Feedstocks, Claudia V. Lopez

All Dissertations

Environmental sustainability represents a challenge for society since industrial growth has a direct impact on natural resources and waste production. New technologies that effectively incorporate waste into renewable resources are critical to the development of a sustainable and circular economy. The manufacturing of structural materials like Portland cement (OPC) is responsible for >8% of the global anthropogenic emissions of carbon dioxide, with ~ 1 kg of CO₂ released to the atmosphere for every kilogram of OPC produced. For instance, the development of sustainable structural materials is a key factor to reduce the greenhouse emissions and to attenuate the climate …

Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, Kayla Ann Foley

Graduate Theses and Dissertations

Poly(ionic liquid)s (PILs) are a fascinating subclass of strong polyelectrolytes formed from polymerizable ionic liquids. As a result of their unique properties and counterion exchangeability, PILs can exhibit conformation structure or material property changes in response to external stimuli such as changes in pH/ionic environment, magnetic fields, and electric potentials. In Chapter 1, a comprehensive review of PILs design as well as their stimuli-responsive behavior is provided. Additional motivation for each dissertation chapter is also discussed. In Chapter 2, magnetically responsive PILs (MPILs) are developed from complexing paramagnetic salts with a random PIL copolymer containing a metal-coordinating co-monomer, acrylamide. A …

Characterization Of Mechanically Recycled Polylactic Acid (Pla) Filament For 3d-Printing By Evaluating Mechanical, Thermal, And Chemical Properties And Process Performance, Mahsa Shabani Samghabady

All Theses

Polylactic acid (PLA) is a biopolymer made from renewable resources such as sugar and corn. PLA filament is a popular material used in Fused Deposition Modeling (FDM) 3D-printing. While this material has many advantages, all the failed parts, support structures, rafts, nozzle tests, and the many prototype iterations during the 3D-printing process contribute to the plastic pollution and release of greenhouse gases. Although PLA is biodegradable, it can take years to degrade in landfills. Instead of throwing away PLA waste and buying new filaments, PLA can be recycled. Amongst the different recycling technologies, mechanical recycling is the most environmentally friendly. …

Functional Nanocomposite Coatings For Use In Food Packaging, Camden N. Webb

Master's Theses

Plastics are a class of materials known for their cost and property advantages, increasing significantly in their usage worldwide. Unfortunately, these benefits come with an increasingly concerning environmental impact. A combination of inadequate disposal options and combinations of materials have led to environmental disasters that will impact generations. One of the worst areas for plastic waste is food packaging. Plastic as a material generally excels at durability and longevity, but as food packaging, it outlives its intended purpose by several orders of magnitude. This leads to plastic food packaging materials sitting in landfill or leading to the environment for hundreds …