Polymer Chemistry Commons^™

Nitro Group Reduction For Use In Organic, Cathodic Materials, Brock G. Goeden

Honors Thesis

The industrial demand for higher capacity, light-weight battery materials has skyrocketed in recent years due to heavy investments in portable electronics, electronic vehicles, and renewable energy sources. However, rechargeable battery technology has seen little improvement since the invention of the Lithium-Ion battery in the 1980s. The low energy density of the traditionally utilized LiCoO2 cathodic material (specific capacity: 272 mAh g-1), has limited its potential to meet these increasing demands. To solve this problem, our research group is investigating new types of lightweight, organic, polymeric materials with conductive backbones as a possible replacement for the cathodic materials in Lithium-Ion batteries. …

Characterization, Immobilization, And Polymer Related Applications Of Watermelon Seed Powder, A Practical Source Of Urease Enzyme, Anthony Quan Quoc Mai

LSU Doctoral Dissertations

Urease enzyme was crystallized almost a century ago, and to this day its intrinsic stability is not ideal for everyday applications. This work introduces a new process by which a naturally encapsulated material, watermelon seed powder (WMSP), is characterized for its stability and activity. WMSP enzymatic activity has been measured for over a year at various storage conditions—exposed to ambient atmosphere for a year, WMSP retained above 90% activity. In aqueous conditions, the enzyme maintained above 60% activity after two months; with the addition of a preservative that number stays at about 90%. There is a pH shift of the …

An Investigation Of Cross-Links On Crystallization And Degradation In A Novel, Photocross-Linkable Poly (Lactic Acid) System, Nicholas Baksh

USF Tampa Graduate Theses and Dissertations

Polymeric molecular structure consists of repeating units bonded together. Mechanicalproperties can be altered without affecting chemical makeup by altering the number of these units. Small molecules can be introduced and/or polymers can be modified to form bonds between molecular chains. Cross-linking, as this is called, also introduces mechanical variation with minimal effects on chemical composition. Lastly, polymer chains reorient themselves in response to intermolecular forces. This temperature dependent response is known as crystallization. Although chemistry is unaltered, mechanical properties can depend highly on the percent of the sample that is crystallized.

Cross-linking is known to enhance the mechanical properties of …

Effects Of Resin Chemistries On The Selective Removal Of Industrially Relevant Metal Ions Using Wafer-Enhanced Electrodeionization, Humeyra B. Ulusoy Erol, Christa N. Hestekin, Jamie A. Hestekin

Chemical Engineering Faculty Publications and Presentations

Wafer-enhanced electrodeionization (WE-EDI) is an electrically driven separations technology that occurs under the influence of an applied electric field and heavily depends on ion exchange resin chemistry. Unlike filtration processes, WE-EDI can be used to selectively remove ions even from high concentration systems. Because every excess ion transported increases the operating costs, the selective separation offered by WE-EDI can provide a more energy-efficient and cost-effective process, especially for highly concentrated salt solutions. This work reports the performance comparison of four commonly used cation exchange resins (Amberlite IR120 Na⁺, Amberlite IRP 69, Dowex MAC 3 H⁺, and …

Multi-Level Analysis Of Atomic Layer Deposition Barrier Coatings On Additively Manufactured Plastics For High Vacuum Applications, Nupur Bihari

Dissertations, Master's Theses and Master's Reports

While hardware innovations in micro/nano electronics and photonics are heavily patented, the rise of the open-source movement has significantly shifted focus to the importance of obtaining low-cost, functional and easily modifiable research equipment. This thesis provides a foundation of open source development of equipment to aid in the micro/nano electronics and photonics fields.

First, the massive acceptance of the open source Arduino microcontroller has aided in the development of control systems with a wide variety of uses. Here it is used for the development of an open-source dual axis gimbal system. This system is used to characterize optoelectronic properties of …

Establishing Independent Tunability Of The Mechanical And Transport Properties Of Polymer Gels, Lucas Rankin

Master’s Theses

Polymer gels can be used in the fabrication of materials for filtering liquid and gaseous media, solid-state electrolytes, and transdermal medical patches. This diverse range of applications primarily relies on the transport and mechanical properties of polymer gels. Both sets of properties have shown excellent tunability, but typically in a coupled fashion. Establishing the independent tunability of the transport and mechanical properties of polymer gels (using simple, cost-effective methods) is paramount if polymer gels are to be used to their full potential. Specifically, block copolymer gels self-assemble into organized nanoscale networks within the gel solvent, which allows for facile control …

Molecular Recognition Of Pet Depolymerization Products And Beta-Cyclodextrin, Thomas Palisin

Williams Honors College, Honors Research Projects

Using molecular recognition techniques to determine the binding constant of the host-guest relationships of the depolymerization products of polyethylene terephthalate (PET) and cyclodextrin species. The main method of data collection used was florescence spectroscopy. Using a titration method and measuring the florescence intensity, a nonlinear regression was used to determine the binding constant.

Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah

Graduate Theses, Dissertations, and Problem Reports (ETD)

Valorization of Xylan in Agroforestry Waste Streams.

Harrison Appiah

Microwave-assisted deep eutectic solvent and gamma-valerolactone metallic chloride catalyzed conversion of xylan to furfural were investigated using a 2x3 factorial experimental design at two levels of percent microwave power, reaction time, and catalyst concentration. The levels of each factor studied were (20%, 60% microwave power, 2, 4 minutes, and 10, 20mg) respectively. The effect of three metallic chloride catalysts (LiCl, FeCl3.6H20, CuCl2) on the conversion of xylan to furfural was also investigated. The gamma-valerolactone-ferric chloride sent system exhibited the highest mean yield of furfural (56.50%). The next highest furfural yield of …

Coaxially Electrospun Fibrous Polymer Scaffolds For Tissue Regeneration And Drug Delivery, Matthew Michael Kleszynski

Graduate Research Theses & Dissertations

A biomaterial is a substance that is specifically engineered to take on a role within the body, either alone or in conjunction with other materials, with the purpose of influencing the body. Using Polymers as a biomaterial is an exciting field of study that has the potential to further our abilities to help those in need. Creating composite nanofibrous scaffolds composed of hydrophobic and hydrophilic polymers may outperform structures made of a single polymer in both in vitro and in vivo environments. Hydrophilicity governs the behavior of polymers in the body and has influence over the mechanical properties of the …

In Depth Characterisation Of The Biomolecular Coronas Of Polymer Coated Inorganic Nanoparticles With Differential Centrifugal Sedimentation, André Perez-Potti, Hender Lopez, Beatriz Pelaz, Abuelmagd Abdelmonem, Mahmoud G. Soliman, Ingmar Schoen, Philip M. Kelly, Kenneth A. Dawson, Wolfgang J. Parak, Zeljka Krpetic, Marco P. Monopoli

Articles

Advances in nanofabrication methods have enabled the tailoring of new strategies towards the controlled production of nanoparticles with attractive applications in healthcare. In many cases, their characterisation remains a big challenge, particularly for small-sized functional nanoparticles of 5 nm diameter or smaller, where current particle sizing techniques struggle to provide the required sensitivity and accuracy. There is a clear need for the development of new reliable characterisation approaches for the physico-chemical characterisation of nanoparticles with significant accuracy, particularly for the analysis of the particles in the presence of complex biological fluids. Herein, we show that the Differential Centrifugal Sedimentation can …

Modeling Mass Transfer And Chemical Reaction In Industrial Nitrocellulose Manufacturing Processes, Francis Patrick Sullivan

Dissertations

A series of models are proposed to describe the production of military grade nitrocellulose from dense cellulose materials in mixtures of nitric acid, sulfuric acid, and water. This effort is conducted to provide a predictive capability for analyzing the rate and extent of reaction achieved under a range of reaction conditions used in the industrial nitrocellulose manufacturing process for sheeted cellulose materials. Because this capability does not presently exist, nitrocellulose producers have historically relied on a very narrow range of cellulose raw materials and resorted to trial and error methods to develop processing conditions for new materials. This tool enables …

Plastic Crystal - Gel Polymer Electrolytes For Magnesium Rechargeable Batteries, Diyana Hambali

Student Works (2020-2029)

Polymer electrolytes are known to be the possible substitution for liquid electrolytes due to their excellent safe performance and good compatibility with electrodes compared to its liquid counterpart. Thus, in the present work, gel polymer electrolytes (GPEs) have been studied comprising plastic crystal succinonitrile (SN) to form plastic crystal - gel polymer electrolytes. The GPEs were prepared by using two types of magnesium salts which are magnesium trifluoromethanesulfonate (MgTf2) and magnesium bis(trifluoromethanesulfonimide) (Mg(TFSI)2) varied from 5 to 30 wt.%. In the preparation of GPEs, four GPE systems were introduced which are single plasticized systems (PVdC-co-AN/SN/MgTf2 and PVdC-co-AN/SN/Mg(TFSI)2) and double plasticized …

Practical Adhesion Measurements In Organic Coatings; Advancing Understanding And Mechanical Methods Development, Diana Gottschalk

Dissertations

“Adhesion” can be considered either a mechanical or chemical phenomenon. The mechanical interpretation describes the difficulty of separating surfaces and is useful for quantifying performance within applications that depend on bulk and interfacial properties. Chemical adhesion describes interfacial resistance to chemical attack and does not depend on bulk properties. Predicting chemical failure through mechanical measurement is confounded by the influence of bulk properties. However, the prospect is attractive because of the robust tolerance for sample geometries, allowing experiments to resemble an end-use system. The present work's primary goal was to elevate mechanical methods to provide a detailed interfacial characterization of …

Synthesis And Characterization Of Water-Soluble Polyaniline For Hydrazine Detection / Hazira Hussin, Hazira Hussin

Student Works (2020-2029)

In this study, polyaniline (PAni) was synthesized through the chemical oxidation method using aniline (Ani) as a monomer, hydrochloric acid (HCl) as a dopant, and ammonium persulphate (APS) as an initiator. PAni was rendered water soluble through treating with cellulose derivatives. Cellulose derivatives such as methylcellulose (MC), hydroxypropyl cellulose (HPC), and hydroxypropyl methylcellulose (HPMC) were used as a stabilizer to improve the solubility of PAni in an aqueous medium. The water-soluble PAni-cellulose derivative was applied as a chemical sensor for hydrazine detection. The chemical structures and electrical conducting behaviours of PAni-cellulose derivatives were investigated using Fourier transform infrared (FTIR) and …

Development Of Plasticized Methylcellulosepotato Starch Blend Based Polymer Electrolytes For Protonic Cell And Supercapacitor Applications, Hamsan Muhamad Hafiz

Student Works (2020-2029)

In the current work, the preparation of the polymer electrolyte (PE) systems consists of methylcellulose-potato starch polymer matrix, ammonium nitrate (NH4NO3) as ionic source and glycerol as plasticizer are done by solution cast technique. X-ray diffraction (XRD) has shown that blend with 60 wt.% methylcellulose and 40 wt.% potato starch possesses the lowest degree of crystallinity. The possible interactions within the PE are verified using Fourier transform infrared (FTIR) spectroscopy. As the concentration of NH4NO3 is at 30 wt.%, the conductivity is optimized up to (4.37 ± 0.16) × 10-5 S cm-1 and then maximized to (1.26 ± 0.1) × …

Effect Of Post-Consumer Content And Bioplastic Incorporation On Polymeric Resin In Consumer Applications, Shelby Bicknell

Electronic Theses & Dissertations

Controversy surrounds the use of plastic products, primarily due to their potentially negative impact on the environment at the end of their lifecycle. The most widely used plastics are manufactured from petrochemicals such as petroleum, coal or natural gas. Petrochemical plastics are not able to readily breakdown in the environment, which aggravates the existing pollution problems. Fortunately, there are eco-friendly alternatives to petrochemical-based plastics. Bioplastics may be derived from renewable sources, biodegradable, or both. Bio-based plastics are plastics that may be derived from renewable biomass sources including, but not limited to, vegetable oils, cornstarch, straw, woodchips, and food waste. They …

Investigation On The Morphology Of Charge-Transfer Complexes In Low Density Polyethylene, Wade Korf

Master's Theses

Fillers are used ubiquitously throughout the fields of polymer and material science to overcome many inherent limitations to polymeric materials (i.e. poor stiffness or strength) and to expand their potential applications. There is a need to develop controllable particle architectures to better understand fundamental structure-property relationships in particle reinforced polymer composites. Charge-transfer complexes (CTCs) can assemble in situ into various needle and dendritic shapes via simple fabrication processes and at low loading levels. In this study, the effect of tetrathiafulvalene (TTF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) CTC crystallites of various shapes and sizes on composite mechanical properties was investigated in an LDPE …

Redox-Active Porous Organic Materials For Electrochemical Energy Storage Applications, K. Shamara Weeraratne

Theses and Dissertations

As the demand for renewable energy technologies grows, so does the need for cheaper, more efficient rechargeable batteries to store the energy. While lithium-ion battery (LIBs) technology is well established, it suffers from limited lithium supplies. Furthermore, the highly toxic transition metals used in the electrodes places a huge burden on the environment. Therefore, replacing lithium with more economical sodium metal in rechargeable batteries (i.e. sodium-ion batteries, SIBs) has garnered considerable attention. Despite the fact that sodium and lithium share similar electrochemical properties, which may cause the transition from lithium to sodium easier, the larger ionic radius of Na^{+ …}

Development Of Novel Adsorbent For Industrial Waste Water Treatment, Islam M. Al-Akraa, Hassan M. Shehata Eng, Dalia A. Ali Eng., Hoda A. Elsawy Dr

Chemical Engineering

The main objective of this research project is to perform some experimental procedures to inform the ability of the novel adsorbent used in this project. The chemical modification of the adsorbent is the chemical oxidation of pure powder chitosan using some specific redox pairs which are potassium dichromate and sodium bisulphite. After preparing the modified chitosan, there are some parameters that must be discussed during the adsorption process. The first parameter is the time parameter, showing experimentally the optimum time for adsorption under certain conditions by collecting values of absorbance and concentration of thymol blue adsorbed after the process from …

Gravity-Drawing Flexible Silicone Filaments As Fiber Optics And Model Foldamers, Katherine Snell

CMC Senior Theses

Here, we present a method of gravity-drawing polydimethylsiloxane (PDMS) silicone fibers with application as fiber optics and as model foldamers. Beginning as a viscous liquid, PDMS is cured using heat until its measured viscosity reaches 4000 mPa•s. The semi-cured elastomer is then extruded through a tube furnace to produce thin (diameters on the order of hundred micrometers) filaments with scalable lengths. PDMS is biocompatible, gas-permeable, flexible, and hydrophobic. Additionally, the PDMS surface hydrophobicity can be modified via UV exposure, O2 plasma, and corona discharge. We demonstrate the patternibility (i.e patterns of hydrophobicity) of PDMS fibers, adding complexity to potential foldamer …

Design Of Pigments For Use In “Cool” Coatings, Tyler Laughorn

Williams Honors College, Honors Research Projects

This project was focused on the development and testing of several novel pigments that exhibit high NIR-reflectance and therefore show potential for use in “cool” coatings. A “cool” coating will reflect more solar radiation than other standard coatings, and so a coated structure would require less energy to keep cool. Four sets of pigments were synthesized: Co_1-xMg_xCr₂O₄ (teal), Co_0.25Mg_0.75Cr_2-yAl_yO₄ (blue), Ti_1-x-yNi_xSb_yO₂ (yellow), and Cr_2-xFe_xO₃ (black). NIR and TSR values were then measured …

Filtration Apparatus Design For Oil-Water Separation Using Membranes And Sponges, Alec Jerger

Williams Honors College, Honors Research Projects

It can be difficult to separate water and oil emulsions through traditional filtration. Therefore, investigations of filtering using thermo-responsive (TR) polymers, in this case poly(vinyl methyl ether) (PVME), was conducted. It’s hypothesized that below its lower critical solution temperature (LCST), PVME has an affinity for water while oil substances do not. Above the LCST the opposite will be true. To verify this hypothesis, iterations of filtration designs were created to provide optimum control over the parameters to measure flow. The final optimized experimental apparatus was a Chromaflex glass column which was air tight and controlled all parameters besides fluid flow. …

A Theoretical And Experimental Study Of Charge Transport In Organic Thermoelectric Materials And Charge Transfer States In Organic Photovoltaics, Ashkan Abtahi

Theses and Dissertations--Physics and Astronomy

Applications of organic electronics have increased significantly over the past two decades. Organic semiconductors (OSC) can be used in mechanically flexible devices with potentially lower cost of fabrication than their inorganic counterparts, yet in many cases organic semiconductor-based devices suffer from lower performance and stability. Investigating the doping mechanism, charge transport, and charge transfer in such materials will allow us to address the parameters that limit performance and potentially resolve them. In this dissertation, organic materials are used in three different device structures to investigate charge transport and charge transfer. Chemically doped π-conjugated polymers are promising materials to be used …

Towards Completely Automated Glycan Synthesis, Matteo Panza

Dissertations

Carbohydrates are ubiquitous both in nature as biologically active compounds and in medicine as pharmaceuticals. Although there has been continued interest in the synthesis of carbohydrates, chemical methods require specialized knowledge and hence remain cumbersome. The need for development of rapid, efficient and operationally simple procedures has come to the fore. This dissertation focuses on the development of a fully automated platform that will enable both experts and non-specialists to perform the synthesis of glycans. Existing automated methods for the synthesis of oligosaccharides are highly sophisticated, operationally complex, and require significant user know-how. By contrast, high performance liquid chromatography (HPLC) …

Decorative Articles Based On Polymeric Materials, Yaser M. Asal Mr., M. A. Radwan, Hany A. Elazab Dr, Bassant Hussein, Mohamed A. Sadek

Chemical Engineering

The aim of the research is to create decorative articles based on polymeric materials, study the effects of fillers and the type of moulds that it can cope with the exothermic reaction nature of resin to create a scientific background on the usage of the resins in daily life products. The polymeric materials that will be concentrated on are the unsaturated polyester resins and epoxy resins. The unsaturated polyester is of many types and chemical constituents, the used experimentally is a general-purpose type and the epoxy also have different types and the used is a commercially 3D floor coating type. …

Thermo-Oxidative Degradation Of Hdpe Geomembranes: Effect Of Phenolic Antioxidant And Hindered Amine Light Stabilizer Concentrations, Yasin Kocak

USF Tampa Graduate Theses and Dissertations

High density polyethylene (HDPE) geomembrane is most common geomembrane which is mainly used for civil engineering applications. However, HDPE geomembrane loses its properties under oxidative degradation progress. This study aims to assess geomembranes which have different percentage of phenolic antioxidant and hindered amine light stabilizer (HALS) with under the six months of the thermal-oxidative degradation. The interactions between phenolic antioxidant, HALS and carbon black can affect the mechanical, physical and chemical properties. To monitor these properties, Differential Scanning Calorimetry (DSC), Fourier-transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectroscopy (SEM/EDX), Melt Index tests, …

Modification And Optimization Of Conducting Polymer-Modified, Redox-Magnetohydrodynamics (R-Mhd) Pumping For Enhanced And Sustained Microfluidics Applications, Md Foysal Zahid Khan

Graduate Theses and Dissertations

In this work, a novel microfluidic pumping approach, redox-magnetohydrodynamics (R-MHD) has improved by materials and device optimization to use in lab-on-a-chip applications. In R-MHD, magnetic flux (B) and ionic current density (j) interacts to generate body force (FB) in between active electrodes, according to the equation FB = j×B. This unique fluid pumping approach is scalable, tunable, generates flat flow profile, and does not require any channels or valves. Pumping performance, such as speed scales with the ionic current density (j) and duration depends on the total charge (Q). The ionic current density (j) results from the conversion of electronic …

Non-Einstein Viscosity Phenomenon Of Acrylonitrile–Butadiene–Styrene Composites Containing Lignin–Polycaprolactone Particulates Highly Dispersed By High-Shear Stress, Sing-Hoon Kim, Kisuk Choi, Kyouk Ryeol Choi, Taesung Kim, Jonghwan Suhr, Kwang Jin Kim, Hyoung Jin Choi, Jae-Do Nam

Mechanical Engineering Faculty Research

Lignin powder was modified via ring-opening polymerization of caprolactone to form a lignin–polycaprolactone (LPCL) particulate. The LPCL particulates were mixed with an acrylonitrile–butadiene–styrene (ABS) matrix at an extremely high rotational speed of up to 3000 rpm, which was achieved by a closed-loop screw mixer and in-line melt extruder. Using this high-shear extruding mixer, the LPCL particulate size was controlled in the range of 3395 nm (conventional twin-screw extrusion) down to 638 nm (high-shear mixer of 3000 rpm) by altering the mixing speed and time. The resulting LPCL/ABS composites clearly showed non-Einstein viscosity phenomena, exhibiting reduced viscosity (2130 Pa·s) compared to …

Implementation Of Multivariate Artificial Neural Networks Coupled With Genetic Algorithms For The Multi-Objective Property Prediction And Optimization Of Emulsion Polymers, David Chisholm

Master's Theses

Machine learning has been gaining popularity over the past few decades as computers have become more advanced. On a fundamental level, machine learning consists of the use of computerized statistical methods to analyze data and discover trends that may not have been obvious or otherwise observable previously. These trends can then be used to make predictions on new data and explore entirely new design spaces. Methods vary from simple linear regression to highly complex neural networks, but the end goal is similar. The application of these methods to material property prediction and new material discovery has been of high interest …

“Polysoaps” Via Raft Copolymerization To Form Well-Defined Micelles For Water Remediation And Targeted Drug Delivery Applications, Phillip Pickett

Dissertations

Amphiphilic copolymers have become increasingly important for environmental and biological applications due to their behavioral characteristics in aqueous solution. For example, structurally-tailored statistical amphiphilic copolymers or “polysoaps” can self-assemble into micelles or other architectures in water at various concentrations. Polysoaps may be differentiated from small molecule surfactant micelles in their capability to self-assemble into unimolecular associates (unimolecular micelles) with no dependence on concentration. Such micelles offer enormous potential for dispersion of hydrophobic species in water at high dilution. Importantly, each polymer chain forms its own micelle and upon dilution, these micelles remain intact and capable of dispersing hydrocarbon material in …