Chemistry Commons^™

Synthesis And Characterization Of Polymeric Materials Derived From Multifunctional Alkyl A-Hydroxymethylacrylates, Jean-Francois Morizur

Dissertations

The research presented in this dissertation covers the investigation of new materials derived from alkyl a-hydroxymethylacrylates (RHMA). The first project exposed in Chapter II involves the synthesis, characterization of RHMA-based reactive surfactants and their successful incorporation in acrylic latexes. The amphiphilic monomers testify of a good copolymerization behavior with other acrylic monomers such as methyl methacrylate and butyl acrylate although their extensive bulkiness. They led to the formation of well-defined polymeric particles via a seeded emulsion polymerization process and permitted decreasing significantly the water sensitivity of the resulting films as compared to film incorporating conventional emulsifier such as sodium dodecyl …

Raft Synthesis Of Water-Soluble, Stimuli-Responsive Ab Diblock Copolymers, Ran Wang

Dissertations

A series of water-soluble, stimuli-responsive AB diblock copolymers were synthesized via the reversible addition-fragmentation chain transfer (RAFT) polymerization technique employing 2-(2- carboxyethylsulfanylthiocarbonylsulfanyl)propionic acid (CTA26) as the RAFT mediating agent.

First, a series of diacid functional trithiocarbonate chain transfer agents (CTA's) were synthesized and examined for their effectiveness as mediating agents in controlling the polymerization of «-butyl acrylate (nBA). Overall, CTA26 demonstrated good control in the homopolymerization of nBA with respect to the molecular weight and the molecular weight distribution, as well as its ability to form block copolymers with high reinitiating efficiency, and thus was chosen as the CTA for …

Semifluorinated Polymers Via Cycloaddition And Nucleophilic Addition Reactions Of Aromatic Trifluorovinylethers, Scott Iacono

All Dissertations

This dissertation encompasses the synthesis, characterization, and properties of semifluorinated polymers derived from thermal polymerization of aryl trifluorovinyl ether (TFVE) monomers. This work is divided into two parts based on the methodology of thermal polymerization using aryl TFVE monomers. The first part of this work involves the thermal [2 + 2]cyclodimerization of aryl TFVE monomers affording perfluorocyclobutyl (PFCB) aryl ether polymers. Chapter 1 provides an overview of PFCB aryl ether polymers as a next-generation class of high performance fluoropolymers that have been successfully employed for a myriad of technologies. PFCB aryl ether polymers are highly desired because of their high …

Carbon Nanotubes And Nanocomposites For Thermal And Electrical Applications, Wei Wang

All Dissertations

The known electrical and thermal properties of carbon nanotubes have prompted many predictions on their extraordinary potentials for ultimately performing polymeric nanocomposites. In this dissertation, chemical modification and functionalization of carbon nanotubes have been demonstrated as being effective for high-quality polymeric carbon nanotube composites, especially with our approach of using polymers that are structurally identical or maximally similar to the matrix polymers in the nanotube functionalization. For example, a poly(N-vinyl carbazole) (PVK) copolymer containing pendant hydroxyl groups was synthesized for the functionalization of single-walled carbon nanotubes (SWNTs). The shared solubility of the functionalized nanotube samples with PVK matrix polymer enabled …

Lignin Degradation In Wood-Feeding Insects, Scott M. Geib, Timothy R. Filley, Patrick G. Hatcher, Kelli Hoover, John E. Carlson, Maria Del Mar Jimenez-Gasco, Akiko Nakagawa-Izumi, Rachel L. Sleighter, Ming Tien

Chemistry & Biochemistry Faculty Publications

The aromatic polymer lignin protects plants from most forms of microbial attack. Despite the fact that a significant fraction of all lignocellulose degraded passes through arthropod guts, the fate of lignin in these systems is not known. Using tetramethylammonium hydroxide thermochemolysis, we show lignin degradation by two insect species, the Asian longhorned beetle (Anoplophora glabripennis) and the Pacific dampwood termite (Zootermopsis angusticollis). In both the beetle and termite, significant levels of propyl side-chain oxidation (depolymerization) and demethylation of ring methoxyl groups is detected; for the termite, ring hydroxylation is also observed. In addition, culture-independent fungal gut …

Systematic Synthesis And Study Of The Structure-Property Relationships Of Arylene Vinylene Polymers., Patrick Lynch

Doctoral

Much is known about the electronic, vibrational and steric effects resulting from the addition of differing organic functional groups as side chains, to the parent conjugated polymer. However the same cannot be said about the substitution of constituents of the polymer backbone itself. To this end a study is presented here which systematically studies the effects of naphthalene and anthracene substitution of the properties of poly phenylene vinylene (PPV) derivative conjugated polymers. The synthesis by the Witting-Horner reaction of derivatives is presented whereby the phenylene units of the PPV structure are methodically substituted by naphthylene and anthrylene units to form …

Reduced Acute Inflammatory Responses To Microgel Conformal Coatings, Amanda W. Bridges, Neetu Singh, Kellie L. Burns, Julia E. Babensee, L. Andrew Lyon, Andrés J. García

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Implantation of synthetic materials into the body elicits inflammatory host responses that limit medical device integration and biological performance. This inflammatory cascade involves protein adsorption, leukocyte recruitment and activation, cytokine release, and fibrous encapsulation of the implant. We present a coating strategy based on thin films of poly(N-isopropylacrylamide) hydrogel microparticles (i.e. microgels) cross-linked with poly(ethylene glycol) diacrylate. These particles were grafted onto a clinically relevant polymeric material to generate conformal coatings that significantly reduced in vitro fibrinogen adsorption and primary human monocyte/macrophage adhesion and spreading. These microgel coatings also reduced leukocyte adhesion and expression of pro-inflammatory cytokines (TNF-alpha, IL-1 beta, …

Symmetrical Dinucleosides, Yousef Ahmadibeni, Keykavous Parang

Pharmacy Faculty Articles and Research

The authors have reported the utility of 1 for the preparation of sulfonamides (J. Org. Chem. 2006, 71, 7915). To the best of the authors’ knowledge, this is the first report of the synthesis of 5¢,5¢-dinucleoside 5¢,5¢-phosphodiesters by using polymer-bound phosphitylating reagents.

Size-Controlled Synthesis Of Monodisperse Core/Shell Nanogels, William H. Blackburn, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Small, monodisperse nanogels (similar to 50-nm radius) were synthesized by free-radical precipitation polymerization and were characterized using a suite of light scattering and chromatography methods. Nanogels were synthesized with either N-isopropylacrylamide or N-isopropylmethacrylamide as the main monomer, with acrylic acid or 4-acrylamidofluorescein as a comonomer and N,N'-methylenebis(acrylamide) as a cross-linker. By varying the surfactant and initiator concentrations, particle size was controlled while maintaining excellent monodispersity. An amine-containing shell was added to these core particles to facilitate subsequent bioconjugation. Successful conjugation of folic acid to the particles was demonstrated as an example of how such materials might be employed in a …

Synthesis Of Multifunctional Nanogels Using A Protected Macromonomer Approach, Neetu Singh, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Nanoparticles possessing multiple functionalities provide synthetic handles for varied surface chemistries, making them useful for a range of applications such as biotargeting and drug delivery. However, the combination of interfering functionalities on the same particle is often challenging. We have employed a synthetic scheme involving chemical protection/deprotection to combine interfering functional groups on the same hydrogel nanoparticle. The synthesis of amine-containing poly(N-isopropylacrylamide) nanogels was carried out via free radical precipitation polymerization by incorporating a Fmoc-protected amine poly(ethylene glycol) (PEG) macromonomer. The Fmoc group was then removed to obtain free amines, which were shown to be available for conjugation. We further …

Chemomechanical Polymers As Sensors And Actuators For Biological And Medicinal Applications, Hans-Jörg Schneider, Kazuaki Kato, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Changes in the chemical environment can trigger large motions in chemomechanical polymers. The unique feature of such intelligent materials, mostly in the form of hydrogels, is therefore, that they serve as sensors and actuators at the same time, and do not require any measuring devices, transducers or power supplies. Until recently the most often used of these materials responded to changes in pH. Chemists are now increasingly using supramolecular recognition sites in materials, which are covalently bound to the polymer backbone. This allows one to use a nearly unlimited variety of guest (or effector) compounds in the environment for a …

Synthesis, Reactions, And Applications Of Bis-Ortho-Diynyl Arene (Boda) Monomers, Polymers, And Derivatives, Mark Perpall

All Dissertations

Bis-ortho-diynyl arenes (BODA) monomers contain two arenediyne functional groups with variable functionality at both the linker group, X, and the alkyne terminal group, R. These arenediyne moieties undergo thermal Bergman reactions to cycloaromatize to naphthyl diradical species. The inclusion of two of these arenediyne functionalities allows the polymer to grow without losing processability and solubility as most aromatic polymers do. The second functionality acts as a solubilizing group until all functionalities are consumed in the fully cured network polymer.
When heated above 800 °C, BODA polymer converts to a high-yield glassy carbon material. This work has been extended …

Surge Of Green: A Sustainable Approach To Conductive Polymers, Bethany Masten

Undergraduate Review

No abstract provided.

A Novel Tio2 / Pvc Layer For Use In A Photoelectrochemical Cell, Faiza Touati, John Cassidy, Kevin Mcguigan

Articles

A novel method of coating titanium dioxide on a glassy carbon electrode as a polyvinylchloride composite , is described. On illumination , there is an enhanced voltammetric current at this TiO2/PVC composite in aqueous formic acid solution. This electrode is used as the basis of a formic acid fuel cell where oxygen is reduced at a platinum cathode. The system yields 100 cm-2 for 0.01 mol dm-3 HCOOH in 0.1 mol dm-3 NaOH under illumination from a 150 W xenon lamp. The current without illumination is 0.5 cm-2.

Synthesis And Characterization Of Arylmethyl Sulfone Dendrimers And Hyperbranched Poly (Phenylene Sulfide) / Poly (Sulfone), Qiuxia Zhao

Seton Hall University Dissertations and Theses (ETDs)

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Synthesis And Characterization Of Highly Conductive Polypyrrole And Polypyrrole/Lignosulfonate/Graphite Composites, Aopeau Imvittaya

Theses and Dissertations

Polypyrrole (PPy) is one of the conductive polymers frequently used in commercial applications, mainly due to its long-term stability and the possibility of forming homopolymers or composites with optimal properties. Polypyrroles were prepared by the chemical polymerization of pyrrole using various methods. The effects of several parameters such as oxidant, dopant type, additives and reaction conditions on the properties of PPy were investigated. In addition, PPy/graphite composites were prepared because graphite is highly conductive and effectively incorporated into the polymer matrix during the polymerization. The amount of graphite in the composite was varied to determine the maximimum conductivity achievable in …

Incompressible And Compressible Boundary Layers On A Fibre In The Melt Spinning Process, John Harding

Doctoral

This thesis seeks to investigate shear stress on and heat transfer from the surface of a fibre in the industrial process of melt spinning. Melt spinning is the process whereby molten polymer materials are extruded through the holes of a device known as a spinneret to create continuous filaments of polymer. Fibres manufactured in this way are used in applications as diverse as fashion and clothing, to telecommunications. The magnitude ofthe shear stress on the fibre surface, and also the rate of heat transfer from the fibre to the surrounding environment are of major importance to the overall quality of …

Polyaniline And Its Derivatives For Environmental Analysis., Atogho Jude Abia

Electronic Theses and Dissertations

Electrooxidation has been used to deposit thin film polyaniline as well as its derivative - thin film poly (ortho-phenylenediamine) (POPD) and poly (meta-phenylenediamine) (PMPD) on carbon electrodes, which are subsequently used to monitor the environmental heavy metal ions (Hg²⁺, Pb²⁺ ,Cd²⁺) through a rather unusual "blocking" of anodic stripping for these metals. Using Hg²⁺ as a model, its cyclic voltammogram for a modified glassy carbon electrode with the resultant polymer shows an enhanced cathodic peak that increases linearly with the analyte ion concentration. POPD also exhibits unique selective detection for organic species. Acetaminophen and …

Investigations Of Poly[(Styrene-Co-P-Methylstyrene)-Risobutylene- R-(Styrene-Co-P-Methylstyrene)] And Poly[(Acrylic Acid)-5-Styrene-Jb-Is0butylene-5-Styrene-Jb-(Acrylic Acid)], James Grabill Kopchick

Dissertations

The pMe study was conducted to understand the morphological and physical property changes that occur as the ratio of pMe to styrene is increased, effectively increasing the aliphatic units. By the introduction of pMe, the interface region becomes more blended/compatible as the pMe migrates to the interface. These pMe groups are theorized in effect to create multiple ‘anchors’ to distribute the loads experienced at the interface more effectively creating a synergistic effect on the final properties of the copolymers. The primary goals of the pentablock study were the characterization of unique membranes as related to …

Isothermal Titration Calorimetry And Transmission Electron Microscopy Of Main-Chain Viologen Polymer Containing Bromide As Counerions, Pradip K. Bhowmik, Marcos A. Cheney, Haesook Han, Longzhou Ma

Transmission Electron Microscope

Polyelectrolytes are an important class of macromolecules that contain dissociable ionic groups. When introduced into polar solvent, usually the universal solvent water, dissociation takes place so that electrically charged macromolecule is suspended in solution. The electrostatic interaction is operative between ionized groups inside the macromolecule, between the macromolecules, between the counterions, and between the macromolecule and counterion. Since this interaction is characterized by its long-range nature, the solution exhibits various interesting properties including the polyelectrolyte behavior very different from solutions of neutral polymers.

Excimer Emission From Cathode Boundary Layer Discharges, Mohamed Moselhy, Karl H. Schoenbach

Bioelectrics Publications

The excimer emission from direct current glow discharges between a planar cathode and a ring-shaped anode of 0.75 and 1.5 mm diameter, respectively, separated by a gap of 250 μm, was studied in xenon and argon in a pressure range from 75 to 760 Torr. The thickness of the “cathode boundary layer” plasma, in the 100 μm range, and a discharge sustaining voltage of approximately 200 V, indicates that the discharge is restricted to the cathode fall and the negative glow. The radiant excimer emittance at 172 nm increases with pressure and reaches a value of 4 W/cm² for …

Analysis Of Plastics In The Tyre Industry Using Fourier Transform Infrared Techniques, Differential Scanning Calorimetry And Softening Point Apparatus, Ching Ching Loh

Student Works (2000-2009)

The plastics in a tyre factory were investigated. The plastics were analysed by FTlR-transmission, FTI.R-ATR, softening point apparatus as well as a Differential Scanning Calorimeter. All the plastics were detected to be polyethene based with melting point range of 107 to 125°C. It was also observed that The FTIR transmission spectrum can be different from the FTIR-ATR spectrum. The FTIR-ATR spectrum gives a higher band intensity at longer wavelengths compared to the FTIR-Transmission spectrum. Interference fringes can be present in the FTlR transmission spectrum. In addition to the above, it was also found that the melting point of plastics obtained …

Alumina And Synthesis Intermediates Derived From Diethylkaluminum Amide, Benzaldehyde And Water, Stephen E. Hall, Lize Wilcox, William S. Tyree, David A. Lindquist, Malay K. Mazumder

Journal of the Arkansas Academy of Science

The reaction of diethylaluminum amide [Et2AINH2] with benzaldehyde in toluene produces a solution of ethylaluminoxane polymer [EtAlO] and hydrobenzamide [PhCH=NCH(Ph)N=CHPh]. Alumina then is precipitated by the addition of water. Transition aluminas that may be useful in heterogeneous catalyst applications are obtained after calcining. Details of the chemistry of solution intermediates according to 1H NMR and the properties of the alumina product according to surface area analyses and powder x-ray diffraction are described.

Modification Of Surface Properties Of Polymeric Materials, Rajesh Sharma, Robert A. Sims, Malay K. Mazumder

Journal of the Arkansas Academy of Science

Polymeric materials are successfully used in virtually all industries ranging from semiconductors, and coatings, to household appliances, automotive, and biomedical implants. Polymers generally have excellent bulk physical and chemical properties. However, certain properties of polymers such as low surface energy, low wettability, and high electrical resistivity sometimes limit their applications. Changing the bulk formulation of the polymers can alter some of these properties, but in general this is not acceptable as it can affect "desirable" bulk properties. Surface modification techniques have been used to alter polymer surfaces without affecting the bulk properties of the material. Most polymers have very high …

Compostability Of Degradable Plastics And Its Use In Solid Waste Disposal / Putri Nadzrul Faizura Bt Megat Khamaruddin., Putri Nadzrul Faizura Megat Khamaruddin

Student Works (2000-2009)

Plastic waste generation and quantity generated is a growing concern in many countries including Malaysia. Plastic waste contributes the third highest waste volume in Malaysian municipal solid waste (MSW) next to putrescible waste and paper. ln the year 2000, plastic waste in MSW of Kuala Lumpur was 24.4% by weight from the MSW and most of the plastic waste was dumped into landfills. Landfills in Malaysia are reducing in its useful life as the amount of waste generated is growing every year by 2% and they have become an undesirable option of getting rid of plastic waste because of the …

Dendritic Polymers As Bonded Stationary Phases In Capillary Electrochromatography, Chiayu Helen Chao

Seton Hall University Dissertations and Theses (ETDs)

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Insight Into The Selectivity Of Molecular Imprinted Polymers, Thomas Patrick O'Brien

Seton Hall University Dissertations and Theses (ETDs)

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Artificial Neural Networks Used To Predict Electrical Properties Of Polymers, Sanjay K. Mitra, Qing Luo, Jerry A. Darsey

Journal of the Arkansas Academy of Science

The ability to predict properties of molecules prior to their synthesis can be of great importance in optimizing their design. Substantial savings in time as well as cost can be achieved if some desired properties can be predicted prior to the synthesis of the molecule. The outer orbitals of a molecule are primarily responsible for many different properties of the molecules. These outer orbital parameters can be utilized by an intelligent computing system like an Artificial Neural Network to extract necessary knowledge about the properties of the molecule. An Artificial Neural Network was trained to extract electrical parameters of several …

New Studies Of Polyfuran And Polymers Of 3-Substituted Furan Rings, Rose M. Mcconnell, Walter E. Godwin, Bradley Phillips

Journal of the Arkansas Academy of Science

No abstract provided.

Macroporous Polymer Synthesis And Characterization: The Role Of Molecular Recognition In The Regioselectivity Of Sucrose Reactions, Gilbert Joshua Matare

Masters Theses

Molecular recognition has recently emerged as a unique technique for making synthetic polymers with selective binding cavities which can stereoselectively and regioselectively bind to a template molecule in a fashion similar to natural enzymes and antibodies. Its industrial applications in chemistry and biomedicine have been recently exploited. Typical examples include the resolution of amino acids, enantio-separation of racemates and bioactive molecules, selective binding of metal ions and in HPLC investigations. Our research is focused on applying molecular recognition studies to improve the regioselectivity of sucrose reactions.

Sucrose is an abundant industrial raw material of immense industrial importance however, its full …