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Liquid Organic Electrolytes: Blends Of Low Molecular Weight Methoxyoligooxyethylene (Mpegs)/Litfsi Salt, Rasha Alshahrani 2017 Atlanta University Center

Liquid Organic Electrolytes: Blends Of Low Molecular Weight Methoxyoligooxyethylene (Mpegs)/Litfsi Salt, Rasha Alshahrani

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

Blends containing methoxyoligooxyethyleneglycol (MPEGs) (MW 350 and 550) and bis(trifluoromethane)sulfonimide lithium (LiTFSI) salt were prepared by solution blending process using tetrahydrofuran (THF) as a solvent. The ionic conductivity of the blends of different compositions were determined at four temperatures i.e. 25°C, 40°C, 60°C and 70°C. A maximum ionic conductivity value of 3.9x10-3 S cm-1 at 25°C was obtained for the blends containing MPEG-350 at an ethylene oxide to lithium salt ratio of 1:10. The ionic conductivity increases with increasing temperature and shows that the ion transport is aided ...


Preparation And Characterization Of Poly(Ethylene Oxide)(Mw 35k And 100k)/ Silica Nanoparticle Composites, Reem Alfinaikh 2017 Atlanta University Center

Preparation And Characterization Of Poly(Ethylene Oxide)(Mw 35k And 100k)/ Silica Nanoparticle Composites, Reem Alfinaikh

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

In recent years, polymer-inorganic nanoparticle compositions have been a subject of considerable interest in order to achieve desired chemical, physical properties and mechanical properties. In this study a polymer nanocomposites have been prepared by incorporating silica nanoparticles (~20 nm) as fillers into poly(ethylene oxide) matrix. The composites of poly(ethylene oxide) and silica nanoparticles were prepared by solution blending. The product composites were powders. The thermal properties of the composites were investigated using the Differential Scanning Calorimetry. The Nuclear Magnetic Resonance (13C solid state, T), Atomic Force Microscopy, X-ray diffraction and Fourier Transform Infrared Spectroscopy were used ...


Construction And Evaluation Of Novel Molecularly Imprinted Polymers (Mips) Using Helical Poly(3-Methyl-4-Vinylpyridine), Fatmah Alshareef 2017 Atlanta University Center

Construction And Evaluation Of Novel Molecularly Imprinted Polymers (Mips) Using Helical Poly(3-Methyl-4-Vinylpyridine), Fatmah Alshareef

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

A novel chiral helical imprinted polymer (MIP) has been prepared by bulk copolymerization of 3-methyl-4-vinylpyridine and a crosslinker using chiral S-mandelic acid as template. The resulting MIPs after removing the template show optical activity that is derived from the presence of chiral helical structures of poly(3-methyl-4-vinylpyridine) (P3M4VP) embedded within the MIP matrix. The basic functional monomer 3-methyl-4-vinylpyridine (3M4VP) was utilized with the acidic template to ensure good interaction between the template and the polymer. Divinylbenzene (DVB) and ethyleneglycoldimethacrylate (EGDMA) with widely varying degree of rigidity, flexibility, and polarity were selected as crosslinking agents. Using two different crosslinkers, it was ...


Electrophilic Cleavage And Functionalization Of Polyisobutylenes Bearing Unsaturations In The Backbone And Synthesis Of Polymers For This Process, Christopher Campbell 2017 The University of Southern Mississippi

Electrophilic Cleavage And Functionalization Of Polyisobutylenes Bearing Unsaturations In The Backbone And Synthesis Of Polymers For This Process, Christopher Campbell

Dissertations

In the first project, we demonstrated a new reaction, which is a subset of the Friedel‑Crafts alkylation reaction, in which the alkylating carbocation undergoes a cleavage reaction prior to reaction with the aromatic substrate. This reaction was discovered by the observation that when a PIB containing a large amount of coupled fraction was subjected to a mixture of protic and Lewis acids (HCl/TiCl4) in the presence of an alkoxybenzene compound, the coupled fraction was quantitatively converted to its constituent monofunctional chains, which became functionalized by the alkoxybenzene.

In the second project, a commercial polymer, poly(isobutylene-co ...


Reintroducing Explicit Solvent To A Solvent-Free Coarse-Grained Model, Seung Ha Kim, Monica H. Lamm 2017 Iowa State University

Reintroducing Explicit Solvent To A Solvent-Free Coarse-Grained Model, Seung Ha Kim, Monica H. Lamm

Monica H. Lamm

A unique coarse-grained modeling scheme that combines a systematic, solvent-free multiscale coarse-graining algorithm for a complex macromolecule with an existing coarse-grained solvent model is proposed. We show that this procedure efficiently and reliably describes the interactions for complex macromolecules, using the specific example of dendrimers binding phenanthrenes in water. The experimentally measured binding capacity is predicted by the unique coarse-grained modeling approach; the conditions for this simulation are beyond what could be reasonably simulated with an all-atom molecular dynamics simulation.


Phase Behavior Of Binary And Polydisperse Suspensions Of Compressible Microgels Controlled By Selective Particle Deswelling, A. Scotti, U. Gasser, E. S. Herman, Jun Han, A. Menzel, L. Andrew Lyon, A. Fernandez-Nieves 2017 Paul Scherrer Institut

Phase Behavior Of Binary And Polydisperse Suspensions Of Compressible Microgels Controlled By Selective Particle Deswelling, A. Scotti, U. Gasser, E. S. Herman, Jun Han, A. Menzel, L. Andrew Lyon, A. Fernandez-Nieves

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We investigate the phase behavior of suspensions of poly(N-isopropylacrylamide) (pNIPAM) microgels with either bimodal or polydisperse size distribution. We observe a shift of the fluid-crystal transition to higher concentrations depending on the polydispersity or the fraction of large particles in suspension. Crystallization is observed up to polydispersities as high as 18.5%, and up to a number fraction of large particles of 29% in bidisperse suspensions. The crystal structure is random hexagonal close-packed as in monodisperse pNIPAM microgel suspensions.We explain our experimental results by considering the effect of bound counterions. Above a critical particle concentration, these cause deswelling ...


Thermal, Mechanical, And Conductive Properties Of Bisimidazolium Thiol-Ene Pil Networks, Sunny Kwan, Sunny Kwan 2017 Murray State University

Thermal, Mechanical, And Conductive Properties Of Bisimidazolium Thiol-Ene Pil Networks, Sunny Kwan, Sunny Kwan

Honors College Theses

Polymers made from thiol-ene reactions are versatile – they can be made from a variety of easily obtainable starting materials and show promise as biomedical materials, hydrogels, resins, and nanoparticles. Ionic liquids (ILs) have uniquely exploitable physical and chemical properties, and polymerization of ILs into polymeric ionic liquids (PILs) enhances or changes these properties, allowing an even wider range of potential applications of ILs in technologies such as fuel cells, solar cells, and even artificial muscles. Bisimidazolium thiol-ene PIL (BITPIL) networks are polymers with each monomer consisting of two moles of bis-imidazolium bridged together with either an alkyl or poly(ethylene ...


Cellulose Reinforced Thermoplastic Composites By In-Situ Ring-Opening Polymerization, Shahab Kashani Rahimi 2017 University of Southern Mississippi

Cellulose Reinforced Thermoplastic Composites By In-Situ Ring-Opening Polymerization, Shahab Kashani Rahimi

Dissertations

Over the past two decades, the increasing concern about the negative environmental impacts of synthetic materials has led to rising interests in utilizing renewable natural resources to develop polymer materials with comparable properties and performance to their synthetic counterparts. One of the major fields of interest is polymer composites where the replacement of synthetic fibers with bio renewable natural fibers is of great potential. However, the processing difficulties, in terms of fiber dispersion and thermal stability have limited the application of cellulosic fibers to polymers with low processing temperatures which are mostly hydrophobic polymers. As a result, the true reinforcing ...


Multi-Scale Assembly Methodologies Of Poly(3-Hexylthiophene) Derivative Systems For Enhanced Optoelectronic Anisotropy, David William Bilger, David William Bilger 2017 California Polytechnic State University - San Luis Obispo

Multi-Scale Assembly Methodologies Of Poly(3-Hexylthiophene) Derivative Systems For Enhanced Optoelectronic Anisotropy, David William Bilger, David William Bilger

Master's Theses and Project Reports

Conjugated polymers represent a class of semi-conducting materials with numerous applications in optoelectronic devices, including organic light-emitting diodes, field-effect transistors, and photovoltaics. Because of the numerous advantages of macromolecular systems, including solution processing and mechanical flexibility, conjugated polymers have become a burgeoning field of research with the hopes of producing cost-effective solution-based electronics. Importantly, optoelectronic device performance is heavily influenced by conjugated polymer backbone orientation and overall thin film morphology. As such, the processing conditions of these systems are important to the construction of high- performance optoelectronics. Polythiophenes are model conjugated polymers that have been studied extensively in halogenated organic ...


Oligo(Ethylene Glycol)-Sidechain Microgels Prepared In Absence Of Cross-Linking Agent: Polymerization, Characterization And Variation Of Particle Deformability, Nicole Welsch, L. Andrew Lyon 2017 Georgia Institute of Technology

Oligo(Ethylene Glycol)-Sidechain Microgels Prepared In Absence Of Cross-Linking Agent: Polymerization, Characterization And Variation Of Particle Deformability, Nicole Welsch, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We present a systematic study of self-cross-linked microgels formed by precipitation polymerization of oligo ethylene glycol methacrylates. The cross-linking density of these microgels and, thus, the network flexibility can be easily tuned through the modulation of the reaction temperature during polymerization. Microgels prepared in absence of any difunctional monomer, i.e. cross-linker, show enhanced deformability and particle spreading on solid surfaces as compared to microgels cross-linked with varying amounts of poly(ethylene glycol diacrylate) (PEG-DA) in addition to self-crosslinking. Particles prepared at low reaction temperatures exhibit the highest degree of spreading due to the lightly cross-linked and flexible polymer network ...


Photopolymerization Synthesis Of Magnetic Nanoparticle Embedded Nanogels For Targeted Biotherapeutic Delivery, Daniel Jonwal Denmark 2017 University of South Florida

Photopolymerization Synthesis Of Magnetic Nanoparticle Embedded Nanogels For Targeted Biotherapeutic Delivery, Daniel Jonwal Denmark

Graduate Theses and Dissertations

Conventional therapeutic techniques treat the patient by delivering a biotherapeutic to the entire body rather than the target tissue. In the case of chemotherapy, the biotherapeutic is a drug that kills healthy and diseased cells indiscriminately which can lead to undesirable side effects. With targeted delivery, biotherapeutics can be delivered directly to the diseased tissue significantly reducing exposure to otherwise healthy tissue. Typical composite delivery devices are minimally composed of a stimuli responsive polymer, such as poly(N-isopropylacrylamide), allowing for triggered release when heated beyond approximately 32 °C, and magnetic nanoparticles which enable targeting as well as provide a mechanism ...


Molecular And Polymeric Materials Based On Asymmetrically Substituted Bf2 3-Cyanoformazanates, Samantha Novoa 2017 The University of Western Ontario

Molecular And Polymeric Materials Based On Asymmetrically Substituted Bf2 3-Cyanoformazanates, Samantha Novoa

Electronic Thesis and Dissertation Repository

This thesis outlines the synthesis and characterization of asymmetric and symmetric 3-cyanoformazanate BF2 complexes and their incorporation into polymers. CuAAC chemistry was used to synthesize two additional asymmetric BF2 complexes and a side product that was identified as a symmetric dimer. Spectroscopic and electrochemical properties of these compounds are described.

Incorporation of an asymmetric 3-cyanoformazante BF2 complex into polymers was done by ROMP. This reaction was used to make homo, block, and random copolymers, where the comonomer was an organic norbornene derivative. Spectroscopic studies of these polymers revealed that, as the mole fraction of BF2 (ƒ ...


Nitric Oxide Release From Poly(Lactic-Co-Glycolic Acid) Nanoparticles And Titanium Alloy, Nina A. Reger 2017 Duquesne University

Nitric Oxide Release From Poly(Lactic-Co-Glycolic Acid) Nanoparticles And Titanium Alloy, Nina A. Reger

Electronic Theses and Dissertations

Current methods for the treatment of bacterial infection involve the use of systemic antibiotics, which are high concentrations of antibiotics delivered over a long period time. Unfortunately, the use of systemic antibiotics can cause harmful side effects to the patient and increases the possibility for antibiotic resistance. The delivery of antibiotics or alternative antimicrobial compounds, such as nitric oxide, directly to the site of infection would decrease the amount of antibiotic necessary to treat a bacterial infection.

Poly (lactic-co-glycolic acid)/polyvinyl alcohol nanoparticles and a titanium- aluminum-vanadium metal oxide alloy implant were surface functionalized to deliver nitric oxide. Polymer nanoparticles ...


Silanol-Assisted Carbinolamine Formation In An Amine-Functionalized Mesoporous Silica Surface: Theoretical Investigation By Fragmentation Methods, Ana P. de Lima Batista, Federico Zahariev, Igor I. Slowing, Ataualpa A. C. Braga, Fernando R. Ornellas, Mark S. Gordon 2017 Instituto de Química

Silanol-Assisted Carbinolamine Formation In An Amine-Functionalized Mesoporous Silica Surface: Theoretical Investigation By Fragmentation Methods, Ana P. De Lima Batista, Federico Zahariev, Igor I. Slowing, Ataualpa A. C. Braga, Fernando R. Ornellas, Mark S. Gordon

Igor I. Slowing

The aldol reaction catalyzed by an amine-substituted mesoporous silica nanoparticle (amine-MSN) surface was investigated using a large molecular cluster model (Si392O958C6NH361) combined with the surface integrated molecular orbital/molecular mechanics (SIMOMM) and fragment molecular orbital (FMO) methods. Three distinct pathways for the carbinolamine formation, the first step of the amine-catalyzed aldol reaction, are proposed and investigated in order to elucidate the role of the silanol environment on the catalytic capability of the amine-MSN material. The computational study reveals that the most likely mechanism involves the silanol groups actively participating in the reaction, forming and breaking covalent bonds in the carbinolamine ...


Fabrication And Applications Of Multifunctional Superhydrophobic Surfaces Based On Surface Chemistry And Morphology, Yang Liu 2017 The Graduate Center, City University of New York

Fabrication And Applications Of Multifunctional Superhydrophobic Surfaces Based On Surface Chemistry And Morphology, Yang Liu

All Dissertations, Theses, and Capstone Projects

Superhydrophobic surfaces are gaining great interests in both fundamental researches and technological applications, because of their unique non-wetting and self-cleaning properties. By mimicking the hierarchical surface structure of the natural superhydrophobic surface, i.e. lotus leaf, numerous artificial surperhydrophobic surfaces were developed. However, the challenge is how to fabricate superhydrophobic surfaces by a scalable and economical method. To address this challenge, our group has developed methodologies that enable the fabrication of superhydrophobic surfaces in inexpensive and potentially scalable ways, such as lamination and 3-D printing. To expand on applications, we also combined other desired functionalities into the superhydrophobic surfaces.

The ...


Processing And Characterization Of Nanocomposites Prepared By High Torque Melt Mixing, Lionel W. Cross Jr 2017 Clark Atlanta University

Processing And Characterization Of Nanocomposites Prepared By High Torque Melt Mixing, Lionel W. Cross Jr

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

The rapid development of polymer nanocomposites has received extensive attention over the last few decades. The ability to alter functionalities of composites, dramatically improving properties and performance at low filler content creates flexibility in designing materials for advanced applications in various industrial fields. This work focuses on nanocomposites relevant to the packaging and aerospace industries.

This work evaluated the ability to homogeneously distribute nanomaterials into a polymer matrix, understand the effects on rheological properties, understand changes to microstructure and effects, and characterize properties of resulting nanocomposite. High torque melt mixing was used to disperse surface modified cellulose nanocrystals in a ...


Regioselective Baeyer–Villiger Oxidation Of Lignin Model Compounds With Tin Beta Zeolite Catalyst And Hydrogen Peroxide, John Adam Jennings, Sean R. Parkin, Eric Munson, Sean Delaney, Julie L. Calahan, Mark Isaacs, Kunlun Hong, Mark Crocker 2017 University of Kentucky

Regioselective Baeyer–Villiger Oxidation Of Lignin Model Compounds With Tin Beta Zeolite Catalyst And Hydrogen Peroxide, John Adam Jennings, Sean R. Parkin, Eric Munson, Sean Delaney, Julie L. Calahan, Mark Isaacs, Kunlun Hong, Mark Crocker

Chemistry Faculty Publications

Lignin depolymerization represents a promising approach to the sustainable production of aromatic molecules. One potential approach to the stepwise depolymerization of lignin involves oxidation of the benzylic alcohol group in β-O-4 and β-1 linkages, followed by Baeyer–Villiger oxidation (BVO) of the resulting ketones and subsequent ester hydrolysis. Towards this goal, BVO reactions were performed on 2-adamantanone, a series of acetophenone derivatives, and lignin model compounds using a tin beta zeolite/hydrogen peroxide biphasic system. XRD, 119Sn MAS NMR spectroscopy, DRUVS and XPS were used to determine tin speciation in the catalyst, the presence of both framework Sn and ...


Graphene Nanoribbons And Their Polymeric Nanocomposites: Controlled Synthesis, Characterization And Applications, Nada M. Aljehany 2017 Pittsburg State University

Graphene Nanoribbons And Their Polymeric Nanocomposites: Controlled Synthesis, Characterization And Applications, Nada M. Aljehany

Electronic Thesis Collection

Carbon based materials are very promising as electrode materials energy generation and storage devices. They have been used for fuel cells, supercapacitors and solar cells. Among the carbon-based materials, graphene is very attractive due to its unique properties such as high electrical conductivity, good mechanical flexibility, large theoretical surface area (2630 m2/g), and high thermal and chemical stability. These unique properties make them very suitable for energy storage applications particularly for supercapacitors. The performance of the graphene as energy storage material could be further improved by growing them in nanoribbon form by unzipping carbon nanotubes. In this thesis ...


Use Of Decahydrodecaborate As Flame Retardants In Polyurethanes, Austin W. Bailey 2017 Pittsburg State University

Use Of Decahydrodecaborate As Flame Retardants In Polyurethanes, Austin W. Bailey

Electronic Thesis Collection

There is a growing need for non-halogenated flame retardants due to the toxicity and environmental impacts that are exhibited by current ones. The polyurethane industry is one that has expressed a need for flame retardants in many of its industrial and commercial applications. For these reasons, two different decaborate compounds, tetramethyl and tetrabutyl ammonium decahydrodecaborate, were synthesized and incorporated into polyurethane films for testing. The compounds were characterized using Fourier Transform Infrared (FT-IR) spectroscopy, Proton-Nuclear Magnetic Resonance (1H-NMR) spectroscopy, Carbon-Nuclear Magnetic Resonance (13C-NMR) spectroscopy, and Boron-Nuclear Magnetic Resonance (11B-NMR) spectroscopy. The compounds were incorporated into a polyol ...


One-Pot Synthesis And Characterization Of A “Click-Able” Polyester Polymer For Potential Biomedical Applications, James F. Beach II 2017 Pittsburg State University

One-Pot Synthesis And Characterization Of A “Click-Able” Polyester Polymer For Potential Biomedical Applications, James F. Beach Ii

Electronic Thesis Collection

In this study, a synthetic polyester polymer was designed using polyethylene glycol, sorbitol, glutaric acid and 4-pentynoic acid as monomers. The synthesis was carried out using standard melt polymerization technique and catalyzed by Novozyme-435, an enzyme suitable for polyesterification of biocompatible compounds. The progress of the reaction was monitored with respect to time and vacuum exposure, with samples being subjected to standard characterization protocols. Polymers with high molecular weight and water solubility were chosen for further modification into folate-functionalized polymeric nanoparticles for targeted drug delivery to cancer cells. This was achieved by employing a solvent diffusion method, wherein the polymer ...


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