Chemistry Commons^™

Free-Radical Polymerization Of Acid-Containing Deep Eutectic Solvents, Kylee Fazende

LSU Doctoral Dissertations

The forefront of this study explored polymerization, specifically thermally-initiated, free-radical frontal polymerization of (meth)acrylic acid monomers while the monomers acted as a hydrogen bond donor of a deep eutectic solvent. These frontal polymerizations were shown to exhibit unusual front velocities and, in some cases, lower front temperatures than the frontal polymerization of the neat monomers or systems containing inert analogs in the place of the hydrogen bond acceptor of these monomer-containing deep eutectic solvents. The frontal polymerization will occur with a range of initiator concentrations including ones that were too low for the pure monomer systems to sustain a front. …

Microgel Core/Shell Architectures As Targeted Agents For Fibrinolysis, Purva Kodlekere, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We demonstrate the utility of microgel core/shell structures conjugated to fibrin-specific peptides as fibrinolytic agents. Poly(N-isopropylmethacrylamide) (pNIPMAm) based microgels conjugated to the peptide GPRPFPAC (GPRP) were observed to bring about fibrin clot erosion, merely through exploitation of the dynamic nature of the clots. These results suggest the potential utility of peptide–microgel hybrids in clot disruption and clotting modulation.

Synthesis Of A Bipyridine Ligand For Metal-Triggered Supramolecular Polymers, Andrew D. Gould

DePaul Discoveries

Intermolecular forces, such as H-bonding, ionic interactions and metal chelation between small molecules, can lead to the assembly of higher-order supramolecular nanostructures. A metal chelator, 2-(Pyridin-2-yl) pyridine-5-carboxylic Acid (a bipyridine derivative), is expected to aid in the formation of supramolecular structures as part of amphiphilic molecules that self-assemble in solution in the presence of metal ions. The bipyridine ligand currently under synthesis can be prepared through a five-step synthesis scheme. The second reaction of this synthesis (the coupling of two pyridine rings) resulted in a combination of the desired 1,2,5-isomer, as well as an unforeseen 1,2,3-isomer. Future research will therefore …

A Detailed Study Of Novel High-Performance Bromine And Phosphorus Based Reactive Flame Retardants In High-Quality Bio-Polyol Based Rigid Polyurethane Foams, Sanket Bhoyate

Electronic Theses & Dissertations

Structural fire is one of the most catastrophic issues related to human safety observed from reports of National Fire Protection Association of United States in past years. Polyurethanes are one of the important structural material used as thermal insulation in housing. They are also used in automotive, construction, medical, packaging, furniture, thermal, electrical, and vibration insulation. Considering this, we have synthesized bio-based polyurethane foams using limonene-based polyol, isocyanates, and other compounds. Flame retardancy was imparted using reactive flame retardant polyols. Firstly, flame retardancy test was performed on the foams using two novel aliphatic and two novel aromatic bromine-based synthesized reactive …

Flame Retardancy Of Ferrocene Incorporated Epoxide, Sultan Alanazi

Electronic Theses & Dissertations

Epoxy resins are thermosetting resins that are used in a variety of applications such as electrical and electronic devices. However, epoxy resins can be inherently flammable. To circumvent this problem, epoxy resins were prepared by incorporating ferrocene carboxylic acid into the epoxy prior to thermal setting, as a flame retardant. Ferrocene carboxylic acid was prepared by condensing o-chlorobenzoyl chloride with ferrocene followed by hydrolysis. The synthesized ferrocene carboxylic acid was characterized by ¹H-NMR spectroscopy, ¹³C-NMR spectroscopy, and FT-IR spectroscopy. Epoxy films were then prepared by reacting ferrocene carboxylic acid (10, 15, and 20% by wt) with bisphenol A …

Nanocomposites Of Polypyrrole And Cobalt Oxide As Efficient And Stable Multifunctional Materials For Supercapacitors And Overall Water Splitting, Ahlam Alghamdi

Electronic Theses & Dissertations

NANOCOMPOSITES OF POLYPYRROLE AND COBALT OXIDE AS EFFICIENT AND STABLE MULTIFUNCTIONAL MATERIALS FOR SUPERCAPACITORS AND OVERALL WATER SPLITTING

An Abstract of the Thesis by

Ahlam Alghamdi

The main objective of this study is to synthesize nanostructured cobalt oxide decorated on polypyrrole using a facile method for energy applications. For this, polypyrrole was first synthesized using a chemical polymerization method. In the second step, a varying amount of cobalt oxide was decorated on polypyrrole using a hydrothermal process. The synthesized materials were structurally and electrochemically characterized. It was observed that the electrochemical properties of the composites depend on their composition. The …

Targeted Triple Drug Regimen For The Treatment Of Prostate Cancer, Tanuja Tummala

Electronic Theses & Dissertations

Prostate cancer is the most common amongst men. According to ACS 2018 statistics, about 164,690 new cases appear and 29,430 deaths occur. Nearly 6 in 10 cases are diagnosed in men over 50 years of age and often there are no early symptoms. The treatment options include surgery, chemotherapy, hormonal therapy and/or radiation and it can often be treated successfully. However, the poor management and adverse effects demanded ways to find better treatment option. Towards the development of a personalized medicine for prostate cancer treatment, we proposed to design prostate cancer targeting magnetic nanoplatform. This integrates various key components such …

Functional Emulsions Via Thiol-Ene Chemistry, Douglas Amato

Dissertations

Polymer particles (micro to nano) with tunable functionality have emerged as a promising and viable technology platform for applications including coatings, cosmetics, nanomedicine, and imaging. Unfortunately, the lengthy polymerization time and lack of intrinsic functionality in the monomers used to fabricate particles is an industrial challenge. Thiol-ene chemistry cirmcumvents these limitations with very rapid polymerization kinetics, high reaction yields, with supressed side reactions and inherent functionality. This dissertation demonstrates the utility of thiol-ene/yne polymerization in miniemulsion and microfluidics to generate functional materials in a one-pot-method. The functionality is typically generated via off-stoichiometry thiol-ene (OSTE) resins which allow for either excess …

Pro-Antimicrobial Networks Prepared Via Degradable Thiol-Ene Acetal Photopolymerization, Sarah Swilley

Honors Theses

A degradable, antimicrobial polymer network with acetal crosslink junctions derived from p-anisaldehyde (pA), a common constituent found in star anise extract, is reported. The p-anisaldehyde was converted into a bis-functional acetal alkene monomer, which serves as a pro-antimicrobial form of the active aldehyde and a building block for materials referred to as pro-antimicrobial polymer networks via degradable acetals (PANDAs). Subsequently, the bis-functional acetal alkene monomer was photopolymerized with a multifunctional thiol to yield a thiol-ene network. PANDAs exhibit surface erosion behavior and yield sustained release of pA over 38 days when exposed to neutral or biologically relevant conditions. The pA …

Biocompatible, Responsive Polysoaps Via Raft Copolymerization For The Delivery Of Model Cancer Therapeutics, Mason Dearborn

Honors Theses

Many chemotherapeutic drugs are small, hydrophobic molecules that require water-soluble, biocompatible nanocarriers for enhanced vascular circulation. Existing polymeric carriers either conjugate the drug along a copolymer backbone or sequester drugs within a protected interior domain to be delivered to specific sites in the body. Such therapeutic systems must overcome a myriad of hurdles, beginning with complex, multi-step syntheses, followed by other inherent barriers that limit the efficiency of drug delivery at the targeted site. This work aims to circumvent a number of these issues using biocompatible, stimuli-responsive polysoaps that are capable of unimeric micelle formation, hydrophobic drug delivery, and triggered …

Polymer Nanocomposites Containing High Aspect Ratio Particulates: Innovation In Co-Extruded Multilayer Barrier Films, Kevin Meyers

Dissertations

Delaminated montmorillonite (MMT) clay/ maleic anhydride grafted LLDPE nanocomposite multilayer films with alternating layers of LDPE were produced through multilayer co-extrusion. The MMT concentration within the nanocomposite layers was increased through annealing the films in the melt due to a mismatch in interdiffusion rates of the polymer layers. Analysis of the nanocomposite layers upon annealing revealed that the platelets impinged upon one another resulting in significant improvement in oxygen barrier in the multilayer system, exceeding the results of bulk nanocomposites.

Model analysis demonstrated that increasing the nanoplatelet aspect ratio or initial concentration in the filled layers would lead to even …

Highly Flame Retardant And Bio-Based Rigid Polyurethane Foams Derived From Orange Peel Oil, Chunyang Zhang

Electronic Theses & Dissertations

Polyurethane is an important class of polymer which is being used for various industrial applications in the form of rigid foams, flexible foams, thermoplastic, elastomer, coating, and adhesive. Especially there is a huge market for rigid polyurethane foams for their applications as thermal insulating material in building and housing. In general, polyurethanes are prepared using polyols and diisocyanates. Most of the polyols used by industries are petrochemical based. In this project, a novel polyol from an orange peel oil-based derivative, limonene dimercaptan, was synthesized using one step photochemical thiol-ene reaction. The synthesized polyol was used to prepare flame retardant polyurethane …

Investigations Into Ring-Opening Polymerization Of Functionalized Ε-Caprolactones, Danielle N. Coderre, Matthew K. Kiesewetter

Senior Honors Projects

Polymers are defined as large molecules constructed from small, repeating units (monomers) which make up everyday items, such as: plastic bags and bottles, waterproof coatings, pipes, etc. H-bonding urea (U) or thiourea (TU) catalysts paired with base cocatalysts used for organocatalytic ring-opening polymerization (ROP) of cyclic esters have been shown to exhibit fast rates of polymerization and result in polymers with controlled molecular weights (Mn) and low polydispersity indexes (PDI). Additionally, organocatalytic ring-opening polymerization (ROP) techniques have been shown to be tolerant of the incorporation of functional groups into the monomer feed, which is vital for the catalytic synthesis of …

Synthesis Of A Silsesquioxane Based Supramolecular Polymer, Rachel Bianculli

Honors Projects

Research toward smart materials, specifically self-healing polymers, is an expanding topic within the materials science field. These materials rely heavily on dynamic crosslinking that is achieved by inducing different degrees of hydrogen bonding, van der Waals forces, etc. This work, demonstrated by research previously done within the Ostrowski research group, shows how coordination bonds of transition metals have been shown to create light activated, self-healing properties. Work done with these light-activated chromium (III) complexes with a poly(butylyene-co-ethylene) backbone have shown how metal—ligand coordination geometries can tune mechanical properties of the polymeric material. However, these materials suffer from being incredibly soft …

Characterization Of Nylon-12 In A Novel Additive Manufacturing Technology, And The Rheological And Spectroscopic Analysis Of Peg-Starch Matrix Interactions, Garrett Michael Craft

USF Tampa Graduate Theses and Dissertations

In this work differential scanning calorimetry, dynamic mechanical analysis, Fourier-Transformed Infrared Spectroscopy [FT-IR] and polarized light microscopy will be employed to characterize polymeric systems. The first chapter broadly covers polymer synthesis and important characterization methods.

In the second chapter, a polyamide (PA12) will be sintered via a novel additive manufacturing (AM) technology developed here at USF termed LAPS (Large Area Projection Sintering). LAPS uses extended sintering timespans to ensure complete melting and densification of the polymer powder over the entire two-dimensional area of the part’s footprint. Further, it allows for the printed layer to crystallize and shrink in its entirety …

Elastin-Like Polypeptide Fusion Tag As A Protein-Dependent Solubility Enhancer Of Cysteine-Knot Growth Factors, Tamina L. Johnson

USF Tampa Graduate Theses and Dissertations

Elastin-like peptide (ELP) fusions promote therapeutic delivery and efficacy. Recombinant proteins, like neurotrophins, lack bioavailability, have short in vivo half-lives, and require high manufacturing costs. Fusing recombinant proteins with genetically encodable ELPs will increase bioavailability, enhance in vivo solubilization, as well as provide a cost-effective method for purification without the need for chromatography. During expression of neurotrophin-ELP (N-ELP) fusions, dense water-insoluble aggregates known as inclusion bodies (IBs) are formed. Inclusion bodies are partially and misfolded proteins that usually require denaturants like Urea for solubilization. Strong denaturants arrest ELPs stimuli-responsive property and increase unwanted aggregation, making purification difficult, yet possible. The …

Characterization Of Polymers Containing Ferrocene And Imidazole With Density Functional Theory, Eric Mullins

Electronic Theses & Dissertations

Electrochemical and UV-Vis studies on these polymers in the presence of aqueous solutions containing metal ions have revealed significant modifications in the electrochemical properties and absorption spectra. These modifications in electrochemical properties could be attributed to the ability of the imidazole to coordinate with metal ions, increasing its electron deficiency and enhancing oxidization of the nearby ferrocene moiety if it is in close proximity with imidazole. However, the mechanism of interaction between the imidazole and metal ions, as well as the equilibrium geometry of the resulting polymer-metal ion complex is unknown.

In this thesis, density functional theory (DFT) was used …

Higher Energy Gap Control Of Fluorescence In Conjugated Polymers, Chien-Hung Chiang

LSU Doctoral Dissertations

Chemo- and biosensors based on fluorescent conjugated polymer benefit from greater detection sensitivity due to amplification of the electronic perturbations produced by analyte binding. This amplification stems from the exciton-transporting properties of conjugated polymers. A conventional design paradigm relies on the analyte binding events which generate sites of lower energy relative to the polymer energy: either fluorescence quenching sites (turn-off sensors) or bathochromically shifted fluorophores (turn-on sensors). In both type sensors, the excitons migrate to the lower-energy site created by analyte binding.

This dissertation primarily focused the investigation of an alternative paradigm when analyte binding creates higher energy gap sites …

Synthesis, Modification, Characterization And Processing Of Molded And Electrospun Thermoplastic Polymer Composites And Nanocomposites, Tamalia Julien

USF Tampa Graduate Theses and Dissertations

This dissertation focuses on the versatility and integrity of a novel, ultrasoft polycarbonate polyurethane (PCPU) by the introduction of nanoparticles and lithium salts. Additionally, the research takes into account the use of electrospinning as a technique to create PCPU and polyimide (PI) fibers. These polymers are of interest as they offer a wide range of properties and uses within the medical and industrial fields.

An industrial batch of an ultrasoft thermoplastic polyurethane (TPU) was synthesized using a two-step process. The first was to create an end capped pre-polymer from methylene bis (4-cyclohexylisocyanate), and a polycarbonate polyol made up of 1,6- …

Synthesis, Characterization, And Assessment Of Cationic Polypeptoids Toward Gene Delivery And Development Of Air Stable N-Substituted N-Thiocarboxyanhydrides, Jessica Michelle Simpson

LSU Doctoral Dissertations

Peptoids are a class of peptidomimetic polymers, which have attracted much attention over the years. Due to their structural similarity to peptides, this group of polymers affords good biocompatibility making them of interest for biomedical applications. This dissertation is largely about the design, synthesis, and characterization of cationic polypeptoids for biological applications, particularly nonviral gene delivery. The dissertation will also cover the development, characterization, and polymerization behavior of a new, air stable N-thiocarboxyanhydride (NTA) monomer.

Introducing functionality, such as small biomolecules and organic compounds can provide distinctive properties to the polymers. Chapter 1 introduces gene therapy and concepts pertinent …

Computational Investigation Of The Ring-Opening Homo- And Co-Polymerizations Of Lactide And Ε-Caprolactone, Diego Garcia, Benjamin Wilson, Joe Fritsch

Seaver College Research And Scholarly Achievement Symposium

The mechanism for the ring-opening polymerization of lactide and ε-caprolactone is presented here with an aluminum-centered catalyst featuring a tridentate ligand and two alkoxide initiating ligands. In each homopolymerization, the addition of electron-withdrawing groups on the tridentate ligand lowers the activation energy of the reaction by increasing the electrophilicity of the central Aluminum. We further investigated the polymerizations by comparing the energy difference between copolymerization and homopolymerization following the initial ring opening as well as the potential for dual polymer chains from the insertion of both initiating ligand. Single chain polymerization is favored in every case, due to lower bond …

Synthesis Of Dimeric Zinc Complexes For Use As Ring Opening Polymerization Catalysts, Kyle D. Brooks, Arnlold Rheingold, David B. Green, Joe Fritsch

Seaver College Research And Scholarly Achievement Symposium

No abstract provided.

Synthesis And Characterization Of Covalent Adaptable Networks Comprised Of Dynamic Imine And Aminal Covalent Bonds, Albert Chao

LSU Doctoral Dissertations

The dissertation is about the design, synthesis and characterization of materials comprised of covalent adaptable networks (CANs). There are three chapters within this dissertation.

Chapter 1 contains a short overview of conventional thermosets and thermoplastics. A new strategy of combining advantages from thermosets and thermoplastics is utilizing dynamic covalent chemistry (DCC) for material design. Dynamic covalent bonds are able to undergo dynamic exchange which allow the material to adapt to a new state when under stimuli such as stress or strain. Material comprised of such reversible networks is called covalent adaptable networks (CANs). These types of reversible covalent bonds followed …

Polymers Course For Small Colleges And Universities, Joseph Furgal

Chemistry Faculty Publications

This article describes the course design and teaching methodology for a polymer chemistry and applications lecture class specifically aimed at small college and university instruction. This intermediate course for advanced undergraduates and masters level graduate students focuses on teaching the basics of polymer history, synthesis and characterization with connections to the core chemistry curriculum in a small class size environment and without a textbook. Furthermore, an extensive overview of the applications of polymeric materials gives students a connection to real life applications. The course includes polymer case studies, informational lessons on real world objects made of polymers, and demonstrations. Student …

Investigation Of Temperature Response Of Photopolymer Material Used For Holographic Sensor, Muhammad Irfan, Tatsiana Mikulchyk, Suzanne Martin, Izabela Naydenova

Conference Papers

Recently, functionalised photopolymer has emerged as a versatile recording material in the field of optical holography due to its novel characteristics and potential use in the development of holographic based sensors, and optical elements. This work describes the temperature response of a newly developed photopolymer, containing of a monomer Nisopropylacrylamide (NIPA) which under photopolymerisation forms a temperature sensitive polymer - Poly(Nisopropylacrylamide) (PNIPA). The photonic sensor was developed by holographic recording of volume phase transmission gratings in a self-processing NIPA-based polymer with a 532 nm laser beam. A 633 nm probe beam was used to monitor real time diffraction efficiency (DE) …

Adsorption Of Tnt, Dnan, Nto, Fox7, And Nq Onto Cellulose, Chitin, And Cellulose Triacetate. Insights From Density Functional Theory Calculations, Guido Todde, Sanjiv K. Jha, Gopinath Subramanian, Manoj K. Shula

Faculty Publications

Insensitive munitions (IM) compounds such as DNAN (2,4-dinitroanisole), NTO (3-nitro-1,2,4-triazol-5-one), NQ (nitroguanidine), and FOX7 (1,1-diamino-2,2-dinitroethene) reduce the risk of accidental explosions due to shock and high temperature exposure. These compounds are being used as replacements for sensitive munition compounds such as TNT (2,4,6-trinitromethylbenzene) and RDX (1,3,5-hexahydro-1,3,5-trinitro-1,3,5-triazine). NTO and NQ in IM compounds are more soluble than TNT or RDX, hence they can easily spread in the environment and get dissolved if exposed to precipitation. DNAN solubility is comparable to TNT solubility. Cellulosic biomass, due to its abundance in the environment and its chemical structure, has a high probability of adsorbing …

Drug Delivery Strategies For The Treatment Of Advanced Lung Cancer And Various Lung Metastases, Elizabeth Bielski

Wayne State University Dissertations

Lung cancer remains the leading cause of cancer-related deaths in the United States. Secondary lung tumors metastasized from other cancer sites also remains highly prevalent, in which most metastatic tumors cannot be cured with existing therapies. Chemoresistance (multi drug resistance – MDR) that develops intrinsically or acquired is one of the key factors leading to fatality in these patients. MDR develops form a variety of resistance mechanisms that can occur consecutively or concurrently, therefore, making most current treatments unsuccessful. Current therapies have known to slow tumor growth, but rarely provide a cure. Immunotherapy has seen some promise, including the use …

Surfactant Driven Assembly Of Freeze-Casted, Polymer-Derived Ceramic Nanoparticles On Grapehene Oxide Sheets For Lithium-Ion Battery Anodes, Ali Zein Khater

Honors Undergraduate Theses

Traditional Lithium-Ion Batteries (LIBs) are a reliable and cost-efficient choice for energy storage. LIBs offer high energy density and low self-discharge. Recent developments in electric-based technologies push for replacing historically used Lead-Acid batteries with LIBs. However, LIBs do not yet meet the demands of modern technology. Silicon and graphene oxide (GO) have been identified as promising replacements to improve anode materials. Graphene oxide has a unique sheet-like structure that provides a mechanically stable, light weight material for LIB anodes. Due to its structure, reduced graphene oxide (rGO) is efficiently conductive and resistive to environmental changes. On the other hand, silicon-based …

Synthesis And Catalytic Testing Of A Proline Functionalized Amphiphilic Block Copolymer, Eric Firestone

Master's Theses and Doctoral Dissertations

Catalysts are reagents used to reduce the amount of energy that a reaction needs to execute, allowing it to proceed at a higher rate while not being consumed. The use of catalyst functionalized amphiphilic copolymer allows easier recovery of the catalyst at the end of the synthesis and allows for the reaction. In water, under appropriate conditions, the amphiphilic block copolymers will form micelles and allow the reaction to occur on the interior of the micelle. The synthesis of amphiphilic copolymer with a hydrophobic O-methacryloyl-trans-4- hydroxy-L-proline and methyl methacrylate end and a hydrophilic acrylic acid end was characterized. The polymer …

Synthesis And Characterization Of Mpims : Metallopolymers Of Intrinsic Microporosity, Kelly Walter

Legacy Theses & Dissertations (2009 - 2024)

Polymers of intrinsic microporosity (PIMs) are class of polymers known for high surface areas arising from their contorted and rigid backbone structures. While high surface area compounds are applicable in many fields, simultaneous solubility and conductivity in PIMs is still lacking. In general, the monomeric units that form the backbone, necessary to yield inefficient polymer strand packing and contortion, also break conjugation in the along the polymer backbone and therefore limit conductivity. It has been previously noted that extended conjugation and the addition of metal atoms (along the backbone) increases conductivity. We therefore sought to use a strategy whereby the …