Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Materials Chemistry (312)
- Engineering (269)
- Organic Chemistry (195)
- Materials Science and Engineering (154)
- Chemical Engineering (120)
-
- Polymer and Organic Materials (105)
- Polymer Science (91)
- Life Sciences (80)
- Physical Chemistry (67)
- Analytical Chemistry (65)
- Inorganic Chemistry (62)
- Physics (59)
- Medicine and Health Sciences (57)
- Other Chemistry (44)
- Biochemistry, Biophysics, and Structural Biology (37)
- Chemicals and Drugs (34)
- Medicinal-Pharmaceutical Chemistry (32)
- Biochemistry (28)
- Biomedical Engineering and Bioengineering (27)
- Environmental Chemistry (27)
- Nanoscience and Nanotechnology (26)
- Mechanical Engineering (24)
- Environmental Sciences (19)
- Biomaterials (17)
- Nanotechnology (16)
- Biotechnology (15)
- Electrical and Computer Engineering (15)
- Institution
-
- The University of Southern Mississippi (158)
- Chulalongkorn University (130)
- University of Massachusetts Amherst (92)
- University of Tennessee, Knoxville (75)
- William & Mary (63)
-
- California Polytechnic State University, San Luis Obispo (55)
- Western University (44)
- Pittsburg State University (40)
- Chapman University (29)
- Western Kentucky University (21)
- City University of New York (CUNY) (20)
- Selected Works (20)
- The University of Akron (20)
- University of South Florida (20)
- University of Arkansas, Fayetteville (19)
- Clemson University (18)
- Louisiana State University (18)
- Technological University Dublin (17)
- University of Kentucky (16)
- Old Dominion University (15)
- Purdue University (12)
- Michigan Technological University (11)
- Murray State University (11)
- East Tennessee State University (10)
- Georgia Southern University (10)
- Missouri University of Science and Technology (10)
- The University of Maine (10)
- University of Nevada, Las Vegas (9)
- Florida International University (8)
- Eastern Michigan University (7)
- Keyword
-
- Polymer (69)
- Polymers (45)
- Chemistry (27)
- Pure sciences (26)
- Drug delivery (21)
-
- Nanoparticles (20)
- Self-assembly (19)
- Applied sciences (18)
- Polyurethane (16)
- Synthesis (16)
- Polymerization (15)
- Conjugated polymers (14)
- Morphology (13)
- Stimuli-responsive (13)
- Block copolymer (10)
- Hydrogels (10)
- Rheology (10)
- Carbon nanotubes (9)
- Epoxy (9)
- Hydrogel (9)
- Nanocomposites (9)
- Nanomaterials (9)
- Photopolymerization (9)
- Surfactant (9)
- Thiol-ene (9)
- Biomaterials (8)
- Coating (8)
- Conductivity (8)
- Electrochemistry (8)
- Graphene (8)
- Publication Year
- Publication
-
- Doctoral Dissertations (150)
- Chulalongkorn University Theses and Dissertations (Chula ETD) (130)
- Dissertations (124)
- Dissertations, Theses, and Masters Projects (63)
- Master's Theses (51)
-
- Electronic Theses and Dissertations (37)
- Electronic Thesis and Dissertation Repository (34)
- Electronic Theses & Dissertations (33)
- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (22)
- Honors Theses (21)
- Masters Theses (21)
- Masters Theses & Specialist Projects (20)
- USF Tampa Graduate Theses and Dissertations (20)
- Williams Honors College, Honors Research Projects (20)
- Theses and Dissertations (18)
- Dissertations, Theses, and Capstone Projects (17)
- Faculty Publications (16)
- All Dissertations (15)
- LSU Doctoral Dissertations (15)
- Articles (14)
- Graduate Theses and Dissertations (11)
- Chemistry Faculty Publications (10)
- Chemistry Publications (10)
- Theses and Dissertations--Chemistry (9)
- FIU Electronic Theses and Dissertations (8)
- Master's Theses and Doctoral Dissertations (7)
- Open Access Dissertations (7)
- Open Access Theses & Dissertations (7)
- Seton Hall University Dissertations and Theses (ETDs) (7)
- Legacy Theses & Dissertations (2009 - 2024) (6)
- Publication Type
Articles 31 - 60 of 1197
Full-Text Articles in Polymer Chemistry
Enhancing Compatibility And Mechanical Properties Of Natural Rubber Composites, Krisma Yessi Sianturi, Adam Febriyanto Nugraha, Belle Kristaura, Mochamad Chalid
Enhancing Compatibility And Mechanical Properties Of Natural Rubber Composites, Krisma Yessi Sianturi, Adam Febriyanto Nugraha, Belle Kristaura, Mochamad Chalid
Journal of Materials Exploration and Findings
Pure natural rubber (NR) exhibits low mechanical properties, necessitating the incorporation of additives like vulcanizing agents and fillers. Carbon black and silica, conventional fillers, are relatively expensive and not environmentally friendly. This study explores using Oil Palm Empty Fruit Bunch (OPEFB) fiber as an affordable, abundant, and biodegradable alternative filler for NR. However, compatibility issues arise between the nonpolar NR and the polar OPEFB fiber. A latex-starch hybrid coupling agent (CA (NR-St)) was added to the composite formulation to address this. NR, OPEFB fiber, and the coupling agent were mixed using an open roll mill with a 10 phr OPEFB …
Dpd Guided Insight On The Formation Process Of Polyethersulfone Membranes By Nonsolvent Induced Phase Separation And The Effects Of Additives, Eric Ledieu
Graduate Theses and Dissertations
Dissipative particle dynamics (DPD), a coarse grain simulation method, was applied to the membrane formation process of non-solvent induced phase separation (NIPS) to gain further insight on the mechanism of certain variables and how they affect the final morphology. NIPS involves two solutions, an organic polymer dissolved in an organic solvent colloquially called the dope and an aqueous coagulation bath, brought into contact with one another. The solvents then mix, causing the polymer to fall out of solution as an asymmetric membrane with a dense surface layer and a more open subsurface layer in response to the decreasing solubility. Polyethersulfone …
Separation Of Organic Acids Through Direct Catalysis From Sugars, Katelyn Robinson
Separation Of Organic Acids Through Direct Catalysis From Sugars, Katelyn Robinson
Chemical Engineering Undergraduate Honors Theses
Society relies on plastic products, whether they are single use or durable. A downside of plastic is that the most common type is a product of oil and oil is not only a limited resource but also a climate-damaging resource. Polylactic acid (PLA) is a bio-based, biodegradable plastic. However, the process of converting biomass to polylactic acid polymer has the largest environmental impact of the PLA production process, so alternative methods of conversion are needed (Moretti et al., 2021). The polylactic acid polymer can be made with lactic acid, which can be converted from glucose.
Understanding The Polymerization Of Ethyl Cyanoacrylate In The Superglue Fuming Of Latent Prints To Optimize Print Retrieval, Leondra Shawntae Lawson
Understanding The Polymerization Of Ethyl Cyanoacrylate In The Superglue Fuming Of Latent Prints To Optimize Print Retrieval, Leondra Shawntae Lawson
Masters Theses
The cyanoacrylate fuming method (CFM) is a widespread process used in forensics to make latent prints visible for detection, acquisition, and analysis. CFM is governed by the reaction of ethyl cyanoacrylate (ECA) with biological components in fingerprints, which serve as initiators for this anionic polymerization. CFM is not a well-controlled polymerization and there are different outcomes that may result from lower temperature, one of which fits the generalization of creating more ion-pair initiators. Another effect could be minimizing termination through suppressing side reactions. Alternatively, when paired with humidity, lower temperatures may cause surface condensation, decreasing the quality of the print. …
New Alkyd Resins From Underutilized Indigenous Seed Oils: Synthesis And Characterization, Aliru O. Mustapha, Hakeem B. Ayoku, Halimah A. Amao
New Alkyd Resins From Underutilized Indigenous Seed Oils: Synthesis And Characterization, Aliru O. Mustapha, Hakeem B. Ayoku, Halimah A. Amao
Karbala International Journal of Modern Science
The underutilization of sesame (Sesamum indicum L.), sweet almond (Prunus amygdalus), and jatropha (Jatropha curcas) seeds indicates a significant resource waste. Nine different varieties of 25% (short), 40% (medium), and 60% (long) alkyd resins were produced from the cross-section of drying, semi-drying, and non-drying oils. A large amount of conversion occurred, with the extent of the reaction (Pav) decreasing as time progressed and the corresponding increase in alkyds' average degree of polymerization (Dp) showing synthesized alkyds. Surface drying from the set-to-dry and dry-through periods climaxed at 2 hours for all the alkyds. Except for alkali, synthesized alkyd resins demonstrated outstanding …
Science Club, Danielle Gibson, Krista Andersen
Science Club, Danielle Gibson, Krista Andersen
Honors Expanded Learning Clubs
Honors After School program for elementary age children to engage with scientific principles. Students performed hands-on experiments to explore various STEM fields. Each weekly lesson consisted of a different concept to be learned or explored by early elementary aged students.
Swelling Studies Of Poly(Ionic Liquids) In Different Solvents And Salt Solutions, Pierson Perdue, Ali Alshaikh, Creighton Baltier, Jason E. Bara, Sourav Chatterjee
Swelling Studies Of Poly(Ionic Liquids) In Different Solvents And Salt Solutions, Pierson Perdue, Ali Alshaikh, Creighton Baltier, Jason E. Bara, Sourav Chatterjee
Scholars Week
Poly(ionic liquid)s (PILs) represented a special class of polymers, which comprised of a polymeric backbone and ionic liquids (ILs) species in each monomeric repeating units. PILs has properties that combined the properties of ionic liquids (ILs) (i.e., high conductivity, better thermal and chemical stability, and tailor-made functionality) with the intrinsic properties of polymer (i.e., mechanical stability). This synergistic property makes PILs a good candidate for various applications such as stable-ion conductors, membranes for gas separations and sorbents. In the past, it was shown that PILs are capable of swelling when dissolved in different ILs but there are few literature reported …
Synthesis And Characterization Of Semi-Interpenetrating And Double Networks Of Sulfonimide- And Imidazolium-Containing Poly(Ionic Liquids), Jeremiah Coughlon, Seth Taylor, Jason Bara, Kevin Miller, Sourav Chatterjee
Synthesis And Characterization Of Semi-Interpenetrating And Double Networks Of Sulfonimide- And Imidazolium-Containing Poly(Ionic Liquids), Jeremiah Coughlon, Seth Taylor, Jason Bara, Kevin Miller, Sourav Chatterjee
Scholars Week
In recent years, there has been increased research interest in creating electrically conductive polymer membranes with materials that are widely available and environmentally safe. Herein, we report how polymeric membranes comprised of unique combinations of ionenes and poly(ionic liquids), including a recently developed sulfonimide- and imidazolium-containing methacryloxy-based monomer, were produced via UV photopolymerization. These membranes were specifically tailored to exhibit both ionic conductivity and an affinity for carbon dioxide, which are both crucial characteristics in such applications as electron transport in lithium-ion batteries and gas sorbency in separation techniques. Monomers, such as the aforementioned methacryloxy-based ionic liquid (IL) and C4VIm, …
Synthesis And Properties Of Bio-Based 3d Printable Resins, Cameron Woods, Seth Taylor, Jeremiah Coughlon, Turner Perdue, Sourav Chatterjee, Jason E. Bara
Synthesis And Properties Of Bio-Based 3d Printable Resins, Cameron Woods, Seth Taylor, Jeremiah Coughlon, Turner Perdue, Sourav Chatterjee, Jason E. Bara
Scholars Week
A photopolymer resin is a monomer that, when introduced to light of a certain wavelength, starts to polymerize into a solid. This has become a growing part of the 3D printing industry. There have been many advancements in the field of 3D printing, however, a lot of these resins are not environmentally friendly and even harmful if not handled in the correct manner. Plant based resins are becoming more and more popular because of their biodegradability and for the possibility of using renewable resources. Glycerol is a plant-based compound that is produced in excess in industry. Glycerol obtained from bioethanol …
Physiochemical Properties Of Urethane-Containing Ionic Liquids And Ionenes From A Non-Isocyanate Synthetic Approach, George Timmermann
Physiochemical Properties Of Urethane-Containing Ionic Liquids And Ionenes From A Non-Isocyanate Synthetic Approach, George Timmermann
Scholars Week
Ionic polymers that are designed to contain ionic liquids (ILs) in their backbones have been shown to exhibit a high degree of variability through changing the type of ionic character and the location of the ionic region within the molecule. This large amount of variability in both the structure and characteristics of ILs allows researchers to design task-specific ionic polymers and ILs for a variety of applications including gas separation membranes and solid polymer electrolytes. The synthesis of a specific class of ILs and ionenes through the incorporation of urethane groups with imidazolium rings by reacting carbonyl diimidazole with various …
Controlling Mechanical Properties Of Well-Defined Polymer Networks, Ipek Sacligil
Controlling Mechanical Properties Of Well-Defined Polymer Networks, Ipek Sacligil
Doctoral Dissertations
Polymer networks are one of the most versatile and highly studied material class that revolutionized many aspects of life. Connecting the final network properties to the molecular parameters of its building blocks remains a major research thrust. Recent advances in network synthesis techniques allowed for accurate predictions of elastic modulus in model networks. Tew Group has developed highly efficient, thiol-norbornene networks with controllable mechanical properties. Chapter 2 focuses on modifying the gel fracture energy predicted by Lake-Thomas theory by accounting for loop defects. This study allowed for a priori estimates of gel fracture energy by combining theory, experiments, and simulations. …
Effect Of Chemical Identity And Morphology On Amphiphilic-Zwitterionic Block Copolymer Membranes, Ria Ghosh
Effect Of Chemical Identity And Morphology On Amphiphilic-Zwitterionic Block Copolymer Membranes, Ria Ghosh
Doctoral Dissertations
Amphiphilic block copolymers have gained a broad research interest attributed to their self-assembly properties over a range of pH, temperature, and ionic strength. Polyzwitterions have attracted special attention due to their hydrophilicity, charge sensitivity and coulombic attraction of the opposite charges over a range of environments making them a popular material of study in the field of stimuli responsive systems, for example in self-healing hydrogels, and water transport membranes. Combining the stimuli responsiveness and higher hydrophilicity of zwitterionic polymers with self-assembly behavior of amphiphilic block copolymers created an interest to study the effect of composition and identity of the zwitterionic …
Vapor Deposition Of Self-Wrinkling Polymer Films, Robert N. Enright
Vapor Deposition Of Self-Wrinkling Polymer Films, Robert N. Enright
Doctoral Dissertations
Initiated chemical vapor deposition is used to grow polymer films on substrates of various three-dimensional shapes which exhibit wrinkling during film growth, termed self-wrinkling. Self-wrinkling avoids separate film growth and compression steps and more-closely mimics processes observed in nature. The self-wrinkling process is elucidated on flat elastic substrates, revealing control over the amount of compressive stress by changing deposition conditions. Next, a study of films grown on liquid substrates with interface profiles that either resemble cylinders or contain repeating concave cones, saddles, and bowls affirms the principle that the wrinkle roundness increases with interface curvature. The selection of high versus …
Microscale Chemical Manipulation And Imaging Using Photoactive Molecules And Light, Uroob Haris
Microscale Chemical Manipulation And Imaging Using Photoactive Molecules And Light, Uroob Haris
Chemistry Theses and Dissertations
Chemical manipulation with light has been an active and growing area of research with important implications in materials science, biotechnology, and environmental science. From early investigations of light sensitive materials for photography in the 19th century, to printing billions of transistors on a semiconductor chip in present day, scientists have gained a deep understanding of photochemistry and the processes that allow us to harness light for everyday applications. In this work, we explore microscale fabrication and molecular imaging using light and photoactive molecules as foundational tools. We develop a visible-light mediated technique for high resolution microscale chemical lithography comprising …
Polyethersulfone Thin-Film Nanocomposite Membrane Embedded With Amine-Functionalized Graphene Oxide For Desalination Applications, Ahmed Bahaeldin
Polyethersulfone Thin-Film Nanocomposite Membrane Embedded With Amine-Functionalized Graphene Oxide For Desalination Applications, Ahmed Bahaeldin
Theses and Dissertations
Thin-film nanocomposite (TFN) desalination membranes were prepared based on a polyethersulfone (PES) support, where the polyamide (PA) layer was embedded with amine-functionalized graphene oxide (GO). The effect of adding various concentrations of functionalized and un-functionalized GO on the desalination performance, hydrophilicity, and morphology of the membranes was additionally assessed throughout this work. Scanning electron microscopy (SEM) measurements were used to assess the morphology of the membranes in combination with Brunauer-Emmett-Teller (BET) analysis. Contact angle measurements were used to gauge the hydrophilicity of the synthesized membranes. The membrane with the best desalination performance contained 1x10-3 wt/vol% of functionalized GO in …
Carbon Dioxide Capture Potential Of Chitosan-Nanocrystalline Cellulose Aerogel Composite Materials: Synthesis, Functionalization, And Characterization, Victor Oghenekohwo
Carbon Dioxide Capture Potential Of Chitosan-Nanocrystalline Cellulose Aerogel Composite Materials: Synthesis, Functionalization, And Characterization, Victor Oghenekohwo
Theses and Dissertations
The carbon dioxide capture technology has been established as an invaluable player in the current global efforts to allay the warming of the planet and climate change. In this connection, the study centers on the valorization of waste organic materials for the application described herein. The sorbents, sourced from a combination of by-products of food processing and agricultural residue waste products, viz. seafood waste and sugarcane bagasse, showed prospects for selective carbon dioxide capture, adsorbing up to 5.78 mg/g of the gas at 273 K and 2.82 mg/g at 298 K, as observed on the Micromeritic ASAP 2020 surface area …
Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent, Anne Sukmawati, Wulan Septiani
Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent, Anne Sukmawati, Wulan Septiani
Journal of Materials Exploration and Findings
Biduri fiber (Calotropis gigantea) is a natural hollow fiber with hydrophobic and oleophilic properties potentially used as oil spilled sorbent from seawater. This study aims to determine the absorption capacity and efficiency of the Biduri fiber and membrane to fuel oil. Measurement of oil absorption to seawater was carried out at various fiber weights (0.5-1.5 g), fiber composition (50-95%), contact time (10-90 minutes), temperature (30 and 50°C), and compared with commercial products. The results showed that the fiber weight variation of 0.5-1.5 g has an average absorption efficiency of 96.67%, and the highest absorption was obtained in a weight of …
Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Mechanical And Conductive Properties, Elizabeth Mcgrew, Kevin M. Miller Phd
Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Mechanical And Conductive Properties, Elizabeth Mcgrew, Kevin M. Miller Phd
Posters-at-the-Capitol
Cellulose, an inexpensive and renewable biomacromolecule, represents an intriguing synthetic foundation for new materials with task-specific properties. Here, we wish to report a synthetic route for functionalizing cellulose with a side chain containing two ionic liquid functional groups using azide-alkyne ‘click’ cyclization strategy, followed by quaternization of the two resulting heterocycles (1,2,3-triazole and imidazole). Through this functionalization strategy, the resulting cellulosic materials exhibited significant softening, with several glass transition (Tg) values observed below room temperature, indicating the amorphous nature of the materials, with the Tg dependent on both the length of the side chain and the …
Structural, Thermal, Optical, And Mechanical Properties Of Composite Films Developed From The Button Mushroom (Agaricus Bisporus)-Sourced High Molecular Weight Chitosan And Potato Starch, Bullyamini Alimi, Monjural Hoque, Shivani Pathania, Jude Wilson, Brendan Duffy, Jesus Maria Frias
Structural, Thermal, Optical, And Mechanical Properties Of Composite Films Developed From The Button Mushroom (Agaricus Bisporus)-Sourced High Molecular Weight Chitosan And Potato Starch, Bullyamini Alimi, Monjural Hoque, Shivani Pathania, Jude Wilson, Brendan Duffy, Jesus Maria Frias
Articles
Films were fabricated using the button mushroom (Agaricus bisporus) sourced high molecular weight chitosan with or without potato starch using the casting method. Glycerol was used as the plasticizer. Chitosan content in the film-forming solution (FFS) was varied (0.5, 0.75 and 1.0% w/v of FFS) while potato starch (1.0% of FFS) and glycerol (25% of the total solid content in the solution) contents were not varied. The control sample contained only chitosan (1.0% of the FFS) and glycerol. The effect of increasing the content of chitosan on the rheological properties of FFS and the properties of the films were investigated. …
Novel Technique In Production Of Pb (Ii)- Imprinted Polymers, Ehab Mohammed, Mostafa M. Elsheikh, Adham A. El-Zomrawy, Farag A. Ahmed
Novel Technique In Production Of Pb (Ii)- Imprinted Polymers, Ehab Mohammed, Mostafa M. Elsheikh, Adham A. El-Zomrawy, Farag A. Ahmed
Al-Azhar Bulletin of Science
Ion imprinting techniques were used to produce ion imprinted polymer (IIP) particles for the selective removal of Pb2+ from aqueous environments. As the Templating monomers, acrylic acid, acrylic amine ligand, and Methylene Bisacrylamide crosslinker were chosen. The imprinted polymer was prepared by free radical polymerization. By leaching with 0.1 M HCl, the (Pb2+) ion was removed from the template. The polymer particles were characterized by IR spectroscopy, Thermal analysis and potentiometric analysis. The produced polymer was mechanically crushed into fine particles, assembled into a sensor probe, and linked to a bare HB graphite pencil electrode (GPE). The sensor has a …
The Affect Of Dha Concentration On Lipid Membrane Fluidity, Elise Rezabeck
The Affect Of Dha Concentration On Lipid Membrane Fluidity, Elise Rezabeck
Williams Honors College, Honors Research Projects
My proposed project will be creating large unilaminar vesicles with varying concentrations of DHA in the vesicles. The diffusion in and out of these vesicles will be tracked by using singular lipid molecules. These singular lipid molecules will be tagged with fluorescence and viewed using an internal reflection fluorescence microscope. The data collected over the course of this project will then be analyzed using Matlab. The result of the project will be to find the specific lipid diffusion constant of these unilaminar vesicles. The relationship between the concentration of DHA and lipid diffusion and membrane fluidity will be found as …
Chemical Decomposition Of Flexible Polyurethane Foam To Generate A Media For Microbial Upcycling, Kaushik Baruah
Chemical Decomposition Of Flexible Polyurethane Foam To Generate A Media For Microbial Upcycling, Kaushik Baruah
Dissertations, Master's Theses and Master's Reports
Polyurethane waste is becoming a global concern as a large amount is being disposed of in landfills every year, and only a fraction is being recycled. Several polyurethane recycling techniques exist, of which ammonolysis and base-catalyzed hydrolysis is the least explored. Flexible polyurethane foam (FPUF) decomposition can generate amines that can act as a carbon source for the growth of microbial consortia. This study aims to generate a novel media capable of microbial upcycling via ammonolysis and base-catalyzed hydrolysis of flexible polyurethane foams (FPUFs) using ammonium hydroxide and subsequently determine the reaction conditions for maximum solubilization of polyurethane foam in …
Application Of Mass Spectrometry For The Characterization Of Synthetic Oligomers And Natural Lignin, Poorya Kamali
Application Of Mass Spectrometry For The Characterization Of Synthetic Oligomers And Natural Lignin, Poorya Kamali
Theses and Dissertations--Chemistry
As part of the ongoing effort to substitute finite fuel and chemical resources with renewable ones, biomass is emerging as one of the most promising sources. Biomass consists of three main components of cellulose, hemicellulose, and lignin. Traditionally, cellulose has been used extensively in pulping industry, while lignin has been considered waste and is burned to generate heat. Lignin, a complex aromatic polymer component of biomass, has the potential to be used as a source of aromatic chemicals and pharmaceutical synthons. The recalcitrant nature of lignin, the lack of effective lignin breakdown methods and analytical techniques to analyze it are …
Analysis Of Fiber Uv Degradation Through An Environmental Chamber, Davis A. Eames
Analysis Of Fiber Uv Degradation Through An Environmental Chamber, Davis A. Eames
Undergraduate Research Posters
Environmentally degraded fibers could impact multiple aspects of a fiber comparison, considering that collected weathered fabrics/fibers may express an altered chemical structure and/or colorimetric property compared to their unexposed counterparts. Depending on the amount of degradation the evidence has suffered, it could be challenging for forensic scientists to make conclusions from their comparative analyses. Observations presented in this study were orchestrated to test the possible outcomes that sunlight has on fabric-based materials. Photodegradation of fabrics was investigated through the use of an environmental chamber for a duration of six weeks, which would be equivalent to three months of real-world UV …
Sunflower Oil-Based Polyol In Flame-Retardant Rigid Polyurethane Foams, Magdalene Asare
Sunflower Oil-Based Polyol In Flame-Retardant Rigid Polyurethane Foams, Magdalene Asare
Electronic Theses & Dissertations
The current shift from solely depending on petroleum sources to seeking renewable alternatives is due to their fast depletion, spike in prices, and the need to reduce our carbon footprint. For instance, the polyurethane industry currently calls for renewable and less toxic polyols and isocyanates for their synthesis over the traditionally used ones. To tackle an aspect of this matter, this work investigates the generation of polyol from sunflower oil, and further probes their use in rigid foams, one of the widely utilized polyurethanes. Epoxidation and ring-opening reactions were used to convert the sunflower oil into a more reactive form, …
Bio-Based Uv-Curable Films And The Effect Of Bio-Content On The Properties Of The Films, Sahilkumar Chaudhary
Bio-Based Uv-Curable Films And The Effect Of Bio-Content On The Properties Of The Films, Sahilkumar Chaudhary
Electronic Theses & Dissertations
The use of renewable resources in film formation has become a new focal point for industry because it is abundantly available and has less carbon emission during production than traditional ones. This has drawn researchers to investigate the functionality of bio-based raw materials and their end-usage. By modifying their chemical structures, the properties of these films like thermal resistance, impact resistance, and chemical resistance can be increased. In this research, limonene was used as a partial replacement for petroleum-based chemicals in film formation. A two-step chemical process was carried out to modify the limonene and the final product was used …
Elucidating The Importance Of Structure, Surfaces, And Interfaces In Polymer Nanoparticles And Nanocomposites, Jacob E. Fischer
Elucidating The Importance Of Structure, Surfaces, And Interfaces In Polymer Nanoparticles And Nanocomposites, Jacob E. Fischer
Doctoral Dissertations
This dissertation details research conducted to elucidate the importance of structure, surfaces, and interfaces in both polymeric nanoparticles and polymer nanocomposites. The fundamental understanding that is garnered in these studies provides a foundation to rationally develop nanocomposites tailored for unique functionalities, performance and applications.
Soft polymeric nanoparticles, have shown to imbue non-traditional diffusive properties, the strength of which decreases with crosslinking density of the nanoparticle. The crosslinking dependent morphology of these nanoparticles is first characterized in a dilute solution of good solvent (Chapter 2). The scattering results revealed that the structure ranges from a swollen polymer in good solvent (0% …
Controlling Polymer Molecular Structure And Morphology: From Illumination Of Conjugated Polymers To Polymer Chain Depolymerization, Josh Moncada
Doctoral Dissertations
Polymers remain a prominent component of our lives, and finding methods to control their structure or morphology are needed to tune material properties. This dissertation reports methods to alter the conformation, morphology, or structure of polymeric materials. Chapter two describes the impact of exposure to white light during annealing of conjugated polymer blends on their morphology and optoelectronic performance. The observed changes in the morphology correlate strongly to the variation in photoluminescence (PL) with illumination, including that the PL varies less with illumination at higher Poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] loadings, offering foundational understanding to guide the structure and optoelectronic performance of conjugated polymer …
Direct Ink Write And Thermomechanical Characterization Of Thermoset Composites, Sergio Dante Favela
Direct Ink Write And Thermomechanical Characterization Of Thermoset Composites, Sergio Dante Favela
Open Access Theses & Dissertations
This research will be divided into two sections. The first section discusses direct ink writing and thermomechanical characterization for thermoset composites. The thermoset ink is prepared with fillers aiding the printing process by modifying the rheology of the ink and geometry retention by allowing for the part to have an initial UV cure step. Three specimen formulations with different weight percentages were printed by material extrusion in the shape of tensile specimens following ASTM standard D638 to characterize the mechanical properties at room temperature, 100â?? and 200â??. Furthermore, the ink resin was characterized through DSC, TGA, and rheology testing. The …
Exploring The Biomedical Applications Of Polyurethane-Based Foams, Films, And Hydrogels, Anand Utpal Vakil
Exploring The Biomedical Applications Of Polyurethane-Based Foams, Films, And Hydrogels, Anand Utpal Vakil
Dissertations - ALL
Shape memory polymers (SMPs) are a class of smart materials that can be temporarily stored in a deformed shape and can actively recover their original shape upon exposure to an external stimulus, such as heat, magnetic field, moisture, pH, light, or electric field. The ability of SMPs to change shape when required can be used for a wide range of applications, especially in the case of minimally invasive biomedical applications. In this work, polyurethane-based SMPs were explored for their use in tissue engineering, drug delivery, and wound healing applications.
In the second chapter, low density porous foams with tunable degradability …