Engineering Commons^™

Insights Into Supported Metal Catalyst Sintering And Their Application For Bio-Oil And Crude Oil Upgradation, Md Fakhruddin Patwary

Theses and Dissertations

Typical heterogeneous catalysts consist of transition metal nanoparticles anchored against sintering on an inert, porous, high temperature stable support. The synthesis of supported catalyst involves pretreatment (drying, reduction) of deposited, ionic metal precursor complexes to form metal nanoparticles. In the first part of this work, we aim to understand the influence of pretreatment (reduction temperature, heating rate, moisture content) on final particle size. Supported nanoparticles of Pt and Pd were synthesized by strong electrostatic adsorption (SEA) and dry impregnation (DI). Reduced samples were characterized by in-situ and ex-situ XRD and STEM. The DI-derived samples generally showed an expected increase of …

Material Development Toward An Index-Matched Gadolinium-Based Heterogenous Capture-Gated Neutron Detector, Aaron J. Thorum

Theses and Dissertations

Neutron detection is important in several fields, especially detection of illicit nuclear material. Historically, 3He has been the basis for these technologies. Modern realities have necessitated the development of new technologies and the exploration of new materials to meet this need. One potential solution is known as capture-gating, which is a measurement approach that is good at differentiating between incident neutrons and gamma rays. The key issue is that materials used in current capture-gating devices can suffer from poor optical performance. This is due to the fact that the these detectors, whether composed of a heterogeneous or homogeneous mixture of …

Simplified Synthesis Of Conjugated Polymers Enabled Via 1,4-Dihydropyrrolo[3,2-B]Pyrrole, Kenneth-John Jack Bell

Master of Science in Chemical Sciences Theses

Conjugated polymers have attracted significant attention as the active layer material in organic electronics, such as organic photovoltaics and light-emitting diodes, partly due to the ability to influence a broad range of properties through structural design motifs. However, high performance conjugated polymers suffer from numerous synthetic steps, generation of toxic waste, and harsh reaction conditions all of which impart additional costs that inhibit their widespread utilization. Therefore, an emphasis on reducing synthetic complexity and utilizing abundant, commercially available starting materials is needed for organic electronics to reach their full potential. Dihydropyrrolo[3,2-b]pyrrole (H₂DPP) chromophores offer a simple one-pot synthesis …

Synthesis And Polymerization Processes Of 1-Chlorine-3- Piperidine -2-Propylmethacrylate Monomer, N U. Pulatova, O S. Maksumova, Izabela Barszczewska Rybarek

Technical science and innovation

An amino alcohol was synthesized on the basis of piperidine and epichlorohydrin. The esterification reaction of methacrylic acids with the obtained amino alcohol was studied. In order to identify optimal synthesis conditions, the influence of temperature, reaction duration and ratio of reactive reagents was investigated. The processes of obtaining unsaturated esters by esterification reactions with 1-chlorine-3-piperidine-2-propanol and acrylic-, methacrylic acids have been studied. The effect of monomer concentration on the rate of polymerization reaction and the yield of polymer formation was studied . The radical polymerization of a new monomer with a piperidine cycle in the presence of a nitrogen-containing …

A Model-Based Framework For The Smart Manufacturing Of Polymers, Santiago D. Salas Ortiz

LSU Doctoral Dissertations

It is hard to point a daily activity in which polymeric materials or plastics are not involved. The synthesis of polymers occurs by reacting small molecules together to form, under certain conditions, long molecules. In polymer synthesis, it is mandatory to assure uniformity between batches, high-quality of end-products, efficiency, minimum environmental impact, and safety. It remains as a major challenge the establishment of operational conditions capable of achieving all objectives together. In this dissertation, different model-centric strategies are combined, assessed, and tested for two polymerization systems.

The first system is the synthesis of polyacrylamide in aqueous solution using potassium persulfate …

Characterization Of Sequential Collagen-Poly(Ethylene Glycol) Diacrylate Interpenetrating Networks And Initial Assessment Of Their Potential For Vascular Tissue Engineering, Dany J. Munoz Pinto, Andrea C. Jimenez-Vergara, T. P. Gharat, M. S. Hahn

Dany J. Munoz Pinto

Collagen hydrogels have been widely investigated as scaffolds for vascular tissue engineering due in part to the capacity of collagen to promote robust cell adhesion and elongation. However, collagen hydrogels display relatively low stiffness and strength, are thrombogenic, and are highly susceptible to cell-mediated contraction. In the current work, we develop and characterize a sequentially-formed interpenetrating network (IPN) that retains the benefits of collagen, but which displays enhanced mechanical stiffness and strength, improved thromboresistance, high physical stability and resistance to contraction. In this strategy, we first form a collagen hydrogel, infuse this hydrogel with poly(ethylene glycol) diacrylate (PEGDA), and subsequently …

Synthesis Of Cadmium Arsenide Semiconductor Nanoparticles, Superatomic Silver Clusters, And Silver Coordination Polymers, Sarthak Jashubhai Patel

Legacy Theses & Dissertations (2009 - 2024)

Nanomaterials have chemical, electronic, optical, and other properties distinct from their bulk counterparts. However, the atom-precise synthesis of these materials remains a challenge, leaving open many scientific questions regarding the size regime between nanoparticulate (quantum confined) and bulk character. In this work, efforts toward the synthesis of nanoparticulate and atom-precise metal and semimetal materials are described. The synthesis of II-V semiconductor Cd3As2 having a near-zero bandgap is discussed. Analysis by UV-Vis absorption spectroscopy and powder X-ray diffraction indicate the formation of material with unexpected crystallinity and absorption properties The interaction between the molecular source of As and the solvent was …

Novel Methods To Produce Large Recombinant Spider Silk Proteins Via Polymerization, Nathan L. Hebert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider silk has long been a subject of scientific research due to its remarkable mechanical properties. Until recently, there has been no way to effectively obtain spider silk except by harvesting it from individual spiders. With advances in technology, the genes that code for the individual spider silk proteins have been isolated and genetically engineered into other hosts to produce recombinant spider silk proteins (rSSp) of varying sizes, Larger rSSp have correspondingly greater mechanical properties in any resulting materials. Using current production methods, larger rSSp cannot be produced in commercially viable quantities while simultaneously being economically viable. The current production …

Using Polymerization, Glass Structure, And Quasicrystalline Theory To Produce High Level Radioactive Borosilicate Glass Remotely: A 20+ Year Legacy, Carol M. Jantzen

Journal of the South Carolina Academy of Science

Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in borosilicate glass. One of the primary reasons that glass has become the most widely used immobilization media is the relative simplicity of the vitrification process, e.g. melt a highly variable waste with some glass forming additives such as SiO₂ and B₂O₃ in the form of a premelted frit and pour the molten mixture into a stainless steel canister. Seal the canister before moisture can enter …

Production Of Porous Alginate Substrates Via Membrane Emulsification For Pharmaceutical Applications, Genesis D. Correa-Rivera, David A. Acevedo, Zoltan K. Nagy

The Summer Undergraduate Research Fellowship (SURF) Symposium

The Food and Drug Administration (FDA) released in 2013 a report that established the pharmaceuticals current good manufacturing practices for the 21^st century. This report encourages the creation of new technology in the pharmaceutical industry. Therefore, this research aims to develop a reliable method to produce porous polymers particles to be used in a novel continuous crystallization in porous substrate. The aim of the current work is to create porous polymer microspheres with uniform particle size distribution using a commercially available membrane emulsification system. In the present study, the emulsification was made using a dispersed phase composed of miglyol …

Expeditious And Eco-Friendly Hydrothermal Polymerization Of Pedot Nanoparticles For Binderfree High Performance Supercapacitor Electrodes, Murugesan Rajesh, C Justin Raj, Byung Chul Kim, Ramu Manikandan, Sung Jin Kim, Sang-Yeup Prof Sang-Yeup Park, Kwangsoo Lee, Kook Hyun Yu

Australian Institute for Innovative Materials - Papers

Poly(3,4-ethylenedioxythiophene) (PEDOT) is a promising conjugated polymer that has attracted attention because of its outstanding electronic properties, useful for a wide range of applications in energy storage devices. However, synthesis of high-quality PEDOT occurs via vapour phase polymerization and chemical vapour deposition techniques using extrinsic hard templates or complicated experimental setups. This study introduces a simple hydrothermal polymerization technique using ferric chloride (FeCl3) as an oxidizing agent to overcome the above drawback, which results in good conductive, crystalline PEDOT nanodendrites and nanospheres. The effects of varying the molar ratio of FeCl3 oxidant were investigated in terms of the structural, morphological …

Optimizing Solvent Blends For A Quinary System, Thomas L. Hoy

Williams Honors College, Honors Research Projects

The Department of Polymer Engineering had received a grant from the Keck foundation to produce a process in which hundreds of copolymers can be formulated, synthesized, analyzed and then extrapolated to produce the optimal polymer for the desired material property. This process involves synthesizing approximately fifty polymers in a custom apparatus, none of which necessarily have the same monomer components. This leads to issue of which solvent or blend of solvents to use that would sufficiently dissolve both monomers and the resulting copolymer. If the monomers are not completely dissolved, a homogenous reaction will be impossible and if the copolymer …

Synthesis And Characterization Of Sr-And Mg-Doped Lagao_3 Powders By Polyvinylpyrrolidone Microwave-Induced Solution Polymerization, Chang Ye, Yuling Zhai, Jian-Zhong Xiao

Dr. Chang Ye

A new chemical route,named microwave-induced polyvinylpyrrolidone(PVP) solution polymerization,has been used to prepare La0.8Sr0.2Ga0.83Mg0.17O2.815(denoted as LS0.2GM0.17) powder.The effect of different contents of PVP as the polymeric carrier was studied and we obtained the optimum amount of PVP,which could ensure the homogenous distribution of the metal ions in its polymeric network structure and inhibit their segregation from the solution.The behavior of the powder after calcination at different temperatures was studied.The PVP solution process consumed less organics compared with traditional Pechini process.Consequently,PVP was a more effective carrier in the preparation of LSGM.High heating rate and more homogenous heating manner without thermal gradient in …

Characterization Of Sequential Collagen-Poly(Ethylene Glycol) Diacrylate Interpenetrating Networks And Initial Assessment Of Their Potential For Vascular Tissue Engineering, Dany J. Munoz Pinto, Andrea C. Jimenez-Vergara, T. P. Gharat, M. S. Hahn

Engineering Faculty Research

Collagen hydrogels have been widely investigated as scaffolds for vascular tissue engineering due in part to the capacity of collagen to promote robust cell adhesion and elongation. However, collagen hydrogels display relatively low stiffness and strength, are thrombogenic, and are highly susceptible to cell-mediated contraction. In the current work, we develop and characterize a sequentially-formed interpenetrating network (IPN) that retains the benefits of collagen, but which displays enhanced mechanical stiffness and strength, improved thromboresistance, high physical stability and resistance to contraction. In this strategy, we first form a collagen hydrogel, infuse this hydrogel with poly(ethylene glycol) diacrylate (PEGDA), and subsequently …

Modeling Of Styrene/Butadiene Co-Polymerization In Emulsion With Monte Carlo Simulation, S.M. Zarand, S. Pourmahdian, F. Taromi, Esmaiel Jabbari, B. Dabir

Esmaiel Jabbari

No abstract provided.

Interfacial Polymerization For Colorimetric Labeling Of Protein Expression In Cells, Jacob L. Lilly, Phillip R. Sheldon, Liv J. Hoversten, Gabriela Romero, Vivek Balasubramaniam, Brad J. Berron

Chemical and Materials Engineering Faculty Publications

Determining the location of rare proteins in cells typically requires the use of on-sample amplification. Antibody based recognition and enzymatic amplification is used to produce large amounts of visible label at the site of protein expression, but these techniques suffer from the presence of nonspecific reactivity in the biological sample and from poor spatial control over the label. Polymerization based amplification is a recently developed alternative means of creating an on-sample amplification for fluorescence applications, while not suffering from endogenous labels or loss of signal localization. This manuscript builds upon polymerization based amplification by developing a stable, archivable, and colorimetric …

Optimization Of The Sequential Polymerization Synthesis Method For Polypyrrole Films, Danial Sangian, Wen Zheng, Geoffrey M. Spinks

Australian Institute for Innovative Materials - Papers

Polypyrrole (PPy) is widely used as an electroactive material and is most often synthesized using electrochemical polymerization. Recently, a new electropolymerization method [1] was introduced that involved preparing the PPy as a sequential series of electrodeposited layers with solvent washing in between each deposited layer. This method enabled high quality PPy free-standing films to be prepared in a relatively short time. The purpose of the present study was to investigate the effect of the polymerization current density on the mechanical and electrical properties of the sequentially polymerized (SEP) PPy films. It was found that a low current density (0.1 mA/cm2) …

Vapor Phase Polymerization Of Edot From Submicrometer Scale Oxidant Patterned By Dip-Pen Nanolithography, Cathal D. O'Connell, Michael J. Higgins, Hiroshi Nakashima, Simon E. Moulton, Gordon G. Wallace

Gordon Wallace

Some of the most exciting recent advances in conducting polymer synthesis have centered around the method of vapor phase polymerization (VPP) of thin films. However, it is not known whether the VPP process can proceed using significantly reduced volumes of oxidant and therefore be implemented as part of nanolithography approach. Here, we present a strategy for submicrometer scale patterning of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) via in situ VPP. Attolitre (10-18 L) volumes of oxidant "ink" are controllably deposited using dip-pen nanolithography (DPN). DPN patterning of the oxidant ink is facilitated by the incorporation of an amphiphilic block copolymer thickener, …

Determining Whether Sequence Differences In Gfa Gene Cause Alexander Disease, Lital Nehama Silverman Webster

All ETDs from UAB

Alexander disease (AxD) is a fatal astrogliopathy usually caused by mutations in the GFA gene, which encodes glial fibrillary acidic protein (GFAP). In this document, two unusual sequence differences in GFA that are associated with AxD are characterized. The first difference is the only reported case of an AxD-causing mutation occurring in a non-coding region of GFA, c.(619-3C>G), resulting in the largest known in-frame deletion in GFAP due to abnormal splicing in a small fraction of the GFA transcripts. The second difference is the farthest reported C-terminal point mutation in GFAP, g.1277A-->T, which produces a Q426L coding change. …

Vapor Phase Polymerization Of Edot From Submicrometer Scale Oxidant Patterned By Dip-Pen Nanolithography, Cathal D. O'Connell, Michael J. Higgins, Hiroshi Nakashima, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Some of the most exciting recent advances in conducting polymer synthesis have centered around the method of vapor phase polymerization (VPP) of thin films. However, it is not known whether the VPP process can proceed using significantly reduced volumes of oxidant and therefore be implemented as part of nanolithography approach. Here, we present a strategy for submicrometer scale patterning of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) via in situ VPP. Attolitre (10^-18 L) volumes of oxidant "ink" are controllably deposited using dip-pen nanolithography (DPN). DPN patterning of the oxidant ink is facilitated by the incorporation of an amphiphilic block copolymer …

Reversible Addition - Fragmentation Chain Transfer In Microemulsions: Effect Of Chain Transfer Agent Aqueous Solubility, Jennifer M. O'Donnell, Eric W. Kaler

Jennifer M. Heinen

Microemulsion polymerizations are attractive for investigating compartmentalization effects in heterogeneous reversible addition - fragmentation chain transfer (RAFT) polymerizations because the propagating radicals are segregated into surfactant stabilized polymer particles, which drastically reduces the effects of biradical termination, Also, microemulsion polymerizations do not involve the large monomer droplets that are present in emulsion and miniemulsion polymerizations. RAFT microemulsion polymerizations of butyl aery late with a high water solubility chain transfer agent, methyl-2-(O-ethylxanthyl)propionate (MOEP), and a low water solubility chain transfer agent, methyl-2-(O-dodecylxanthyl)propionate (MODP), were investigated to determine the effect of chain transfer agent compartmentalization on the control of the polymerization. The …

Transient Study Of The Wetting Films In Porous Media Using 3d X-Ray Computed Micro-Tomography: Effect Of Imbibition Rate And Pore Geometry, Pradeep Bhattad

LSU Doctoral Dissertations

Imbibition in porous media is governed by the complex interplay between viscous and capillary forces, pore structure and fluid properties. Understanding and predicting imbibition is important in many natural and engineered applications; it affects the efficiency of oil production operations, the moisture and contaminant transport in soil science, and the formation of defects in certain types of composite materials. Majority of the studies published on the transient imbibition behavior in a porous medium were conducted in the simplified 2D transparent micromodels or the 2D projection visualization (X-ray or visible light) of the 3D porous medium. However, the pore level transient …

Materials And Coatings Derived From The Polymerizable Ionic Liquid Surfactants 1-(2-Acryloyloxyundecyl)-3-Methylimidazolium Tetrafluoroborate And 1-(2-Acryloyloxyundecyl)-3-Methylimidazolium 2-Acrylamido-2-Methyl-Propylsulfonate, Hong Gu

Master's Theses and Doctoral Dissertations

Polymerizable ionic liquid surfactants were synthesized and polymerized, yielding engineered advanced polymers that can be tailored for diverse applications. First, 1-(2-acryloyloxyundecyl)-3-methylimidazolium tetrafluoroborate (IL-BF₄) was synthesized and was copolymerized with methyl methacrylate (MMA) via microemulsion polymerization. The resulting polymer gels can be transformed into porous materials by anion exchange, and the porosity of the material can be tuned through the solvent shifting. Second, an ionic liquid composed of a 1-(2-acryloyloxyundecyl)-3- methylimidazolium (IL) cation and 2-acryloamido-2-methyl-propylsulfonate (AMPS) anion was synthesized and polymerized by UV irradiation, and introductory data are illustrated for humidity sensitive preparations suitable for chemFETs, for proton conducting …

Materials And Coatings Derived From The Polymerizable Ionic Liquid Surfactant 1-(2-Acryloyloxyundecyl)-3-Methylimidazolium Bromide, Dustin England

Master's Theses and Doctoral Dissertations

The polymerizable ionic liquid surfactant, 1-(2-acryloyloxyundecyl)-3- methylimidiazloium bromide (IL-Br) was synthesized. The ternary phase diagram of the ILBr/ MMA/water system was constructed at 25 and 60 °C. Several microemulsion polymerizations were carried out, yielding materials that ranged from latexes, which formed transparent films upon drying, to solid rods. These materials were analyzed by various methods. Latex stability in several salt solutions was tested. Homopolymers and copolymers of IL-Br and MMA were produced by bulk and solution thermal polymerization. Bulk polymerized materials were insoluble in several solvents, suggesting light cross-linking. Solution polymers were soluble in DMF and were analyzed by SEC …

Microstructure Evolution And Monomer Partitioning In Reversible Addition - Fragmentation Chain Transfer Microemulsion Polymerization, Jennifer M. O'Donnell, Eric W. Kaler

Jennifer M. Heinen

Small-angle neutron scattering (SANS) studies of reversible addition - fragmentation chain transfer (RAFT) microemulsion polymerizations of butyl acrylate and 2-ethylhexyl acrylate with the RAFT agent methyl-2-(O-ethylxanthyl) propionate (MOEP) allow the observed rate retardation to be attributed to slow fragmentation of the macro-RAFT radical. Microemulsion polymerization allows the RAFT mechanism to be investigated in the absence of termination reactions so that the cause of the rate retardation frequently observed in both homogeneous and heterogeneous polymerizations may be isolated. However, the concentration of monomer at the locus of polymerization (Cmon(part)) must be known as a function of conversion before a mechanistic study …

Role Of Intrinsic Kinetics And Catalyst Particle Size Distribution In Cfd Simulations Of Polymerization Reactors, Rong Fan, Rodney O. Fox, Michael E. Muhle

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

Fluidized-bed reactors are widely used in the production of polyethylene. In this work, the quadrature method of moments (QMOM), a chemical reaction engineering (CRE) model, and computational fluid dynamics (CFD) are combined to investigate the role of intrinsic kinetics and the catalyst particle size distribution (PSD) in a gas phase fluidized bed reactor. The catalyst PSD is represented by a few nodes using the QMOM and an intrinsic rate model based on the age of particles is used to solve the evolution of particle temperature, particle size, and catalyst sites with age. Assuming the particle age distribution is well-mixed, the …

Surface Modification Of Su-8 By Photografting Of Functional Polymers For Lab-On-A-Chip Applications, Zhan Gao, David Henthorn, Chang-Soo Kim

Chemical and Biochemical Engineering Faculty Research & Creative Works

Due to the high flexibility and versatility in the process development of microfluidic devices, an epoxybased, high-aspect ratio photoresist SU-8 is now attracting attention as the main structuring material of the fluidic channels. Manipulation of the surface properties of SU-8 channel wall is critical to attach functional films such as enzyme-immobilized layers or biocompatible layers. We describe a new in situ patterning method to form a hydrogel film on SU-8 by a photografted polymerization procedure. The hydrophobic surface of SU-8 is modified using a surface bound initiator HCPK (1-hydroxycyclohexyl phenyl ketone). A p-HEMA (poly-2-hydroxyethylmethacrylate) hydrogel film is grafted by photopolymerization …

3-D Numerical Simulation Of Reactive Extrusion And Its Application To Polymerization Of Ε-Caprolactone In Co-Rotating Twin-Screw Extruders, Linjie Zhu

Dissertations

A 3-D numerical simulation model was proposed to predict the polymerization of ε-caprolactone in fully-filled conveying elements and kneading blocks of co-rotating twin-screw extruders, in which the kinetics equation for polymerization is coupled with continuity equation, momentum equation, and energy equation. With the 3-D model, parametric studies have been carried out to investigate the effects of screw configurations, screw diameter, operational conditions, values of heat from reaction, initiator concentration, and heat transfer conditions at barrel surface upon the polymerization progress. Two simulation models for the polymerization in the partially-filled channels were developed based on the conveying mechanisms of the reaction …

Relationship Between Alkaline Pulp Yield And The Mass Fraction And Degree Of Polymerization Of Cellulose In Pulp, Mehmet Sefik Tunc

Electronic Theses and Dissertations

Wood as a raw material is generally the dominant cost factor for the production of chemical pulp. Therefore, an increase in pulp yield has a major impact on the competitiveness of a mill. In order to optimize pulp yield, for example by changing operating conditions, a mill must be able to monitor the yield accurately. However, an accurate "real-time" pulp yield measurement method is not available at the present time. Pulping yield is presently measured from the amount of pulp produced from a given quantity of wood consumed over a 3 to 6 month time frame. This method is obviously …

Dynamic Modeling And Parameter Estimation For An Ethlyene-Propylene-Diene Polymerization Process, Rujun Li

LSU Doctoral Dissertations

New Page 1

A general dynamic model for continuous EPDM polymerization in which crosslinking and gel formation are attributable to reactions between pendant double bonds has been developed. A pseudo-kinetic rate constant method is introduced to construct a moment model for a pseudo-homopolymer that approximates the behavior of the actual terpolymer under long chain and quasi-steady state assumptions. The pseudo-homopolymer model is then used as the basis for application of the numerical fractionation method. The proposed dynamic model is capable of predicting polydispersities and molecular weight distributions near the gel point with as few as eleven generations, and in the …