Chemical Engineering Commons^™

A Novel Biomaterial Platform For Cardiac Tissue Engineering, Andrew House

Dissertations

Heart disease is one of the leading causes of death in the world. With a growing demand for in vitro cardiac models that can recapitulate the complex physiology of the cardiac tissue, there is a desire to create novel therapies and treatments. However, due to a lack of fundamental understanding of the heart's inflammatory response to myocardial infarction, the development of new therapies is both time consuming and costly. In this work, a novel approach to fabricating a dynamic hydrogel cardiac platform is reported. This platform better mimics the dynamic changes occurring in the native cardiac tissue microenvironment during cardiac …

Structure And Dynamics Of Lignin In Condensed Phase For Biomass Conversion, Nusrat Jahan

Theses and Dissertations

Lignocellulosic biomass represents the largest potential volume and lowest cost for biofuel and biochemical production. Harnessing the full potential of the lignocellulosic biomass for low-carbon energy requires the knowledge of efficient breakdown and fractionation of its carbohydrates and lignin. Organic solvent pretreatment is recognized as an emerging way ahead because of its inherent advantages, such as the ability to fractionate lignocellulosic biomass into cellulose, lignin, and hemicellulose components with high purity, as well as easy solvent recovery and solvent reuse. Through all-atom MD simulation, we analyze the conformational transition of diverse lignin molecules in varying concentration of Methanol/water , DMSO/water …

Towards High-Rate Thermoplastic Composites, Chris Croshaw

Dissertations

This dissertation attempts to identify and address the problems associated with high-rate thermoplastic composites. Herein, three primary research thrusts were investigated; the first two chapters focus on the melt-state degradation mechanism of PEKK copolymers and its role on downstream crystallization and thermomechanical properties, the third chapter examines the role of graphene nanoplatelets (GNP) on the crystallization and melting behavior of PEKK 70/30, and the final chapter focused on radio frequency and induction heating of PEKK nanocomposites.

The melt-state degradation mechanism was identified using a combination of x-ray photoelectron spectroscopy (XPS), molecular dynamics (MD), and quantum mechanics (QM) simulations. Melt-state degradation …

Programming The Properties Of Branched Polymers Through Precision Architectures, Michael R. Dearman

LSU Master's Theses

The glass transition of branched polymers is determined by multiple structural parameters that dictate their inter- and intramolecular interactions, and ultimately, their molecular packing in the amorphous phase. Here we examined the impact of side chain length, backbone length, molecular weight composition, and topology on the glass transition behavior of bottlebrush polymers. Through examining precision bottlebrush polymer libraries (PBP, ĐSC = 1.0), we find the infinite molecular weight Tg is reached at a specific brush length after which the effect of the side-chain length dominates. Being a factor more dominant than the backbone, side-chain length affects the Tg of bottlebrush …

Carbon Fibers From Bio-Based Precursors Derived From Renewable Sources, Sagar Kanhere

All Dissertations

Carbon fibers have the highest strength and modulus among all known fibers and are used as reinforcements in high-performance composites [1]. Carbon fibers also have a very low density relative to metals. Therefore, carbon fibers possess ultrahigh specific strength and modulus, which make them desirable for high-performance light-weight composites. A vast majority of commercial carbon fibers are produced from PAN precursors that are expensive, which limits the use of PAN-derived carbon fibers to aerospace applications (e.g., airplanes). However, for costsensitive applications, there is a need for low-cost, moderate performance carbon fibers. Lignin is a low-cost by-product of pulping and biorefining …

Sustainable Material For Urea Delivery Based On Chitosan Cross-Linked By Glutaraldehyde Saturated Toluene: Characterization And Determination Of The Release Rate Mathematical Model, Jayanudin Jayanudin, Retno S. D. Lestari, Indar Kustiningsih, Dandi Irawanto, Rozak Rozak, Reyonaldo L. A. Wardana, Fakhri Muhammad

Karbala International Journal of Modern Science

The aims of this study were to characterize the urea-loaded chitosan microspheres and determine the release kinetic constants and diffusion coefficients. An emulsion cross-linking method was used to prepare the urea-loaded chitosan microspheres. Urea was dissolved in a solution of chitosan then put into vegetable oil and stirred to form an emulsion. Glutaraldehyde saturated toluene (GST) was added into the emulsion dropwise while continuously stirring for the solidification process. Chitosan microspheres filled with urea were washed, dried, and then analyzed. Characterization of the urea-loaded chitosan microspheres was conducted using a scanning electron microscope (SEM), Raman spectroscopy, X-ray diffraction, and particle …

Application Of The Core Shell Model For Strengthening Polymer Filament Interfaces, Yu-Chung Lin, Aniket Raut, Yiwei Fang, Yifan Yin, David Sprouster, Tai-De Li, Guillaume Freychet, Mikhail Zhernenkov, Steve Nitodas, Jonathan Sokolov, Yuval Shmueli, Miriam Rafailovich

Advanced Science Research Center

While surface segregation has been intensively studied in thin films, relatively little has been investigated in filament geometries. In contrast to thin films, the filament surface forms a continuum, with interactions both at the free air and internal filament interface, which makes it difficult to achieve an equilibrium configuration. This asymmetry has become particularly apparent with the increasing use of additive manufacturing where entire structures are constructed via layered deposition of filamentous layers from a moving thermal nozzle. In addition, this process is highly non-equilibrated with poor thermal retention and is responsible for insufficient filament–filament interfacial fusion and internal pore …

Experimental Study On Co2-Sensitive Polyacrylamide As Potential In-Situ Sealing Agent For Co2 Leakage Pathways In Geological Storage Sites, Iris Laihmen Quan Lopez

Theses and Dissertations

As the world pushes for ‘greener’ technologies and carbon neutrality, efforts have focused on creating novel ways to mitigate humankind’s carbon footprint. Carbon capture and storage (CCS) has become a prevalent technique that has proven to be an effective long-term method to safely relocate excess carbon dioxide (CO₂) into subsurface formations. However, CCS is a newer technique which requires constant monitoring due to potential leakage pathways present in CO₂ storage sites; therefore, a preventive approach to seal leakage pathways is recommended. This dissertation explores the potential of CO₂-sensitive polyacrylamide (CO₂-SPAM) as a novel …

Development Of A New Affinity Membrane For Rapidly Purifying Non-Antibody Proteins, Friendship Edioma

All Theses

This thesis project describes the modification and evaluation of a new affinity membrane for rapid chromatographic purification of non-antibody proteins. The affinity membrane utilizes Im7/CL7 coupling technology developed by Dr. Vassylyev's lab at the University of Alabama Birmingham (UAB), licensed by TriAltus Bioscience. The behavior of the membrane was evaluated using purified CL7-tagged Cas9 as my model protein for static and dynamic binding capacity analysis.

Chapter one provides an overview on biopharmaceutical drug production process development. I discuss how protein drugs are produced, isolated, and purified from the cell supernatant after upstream phases are completed. Despite increasing demands for biologics, …

Effect Of Temperature, Catalyst Concentration And Time, On Polylactic Acid Production From Sisal Boles Juice By Ring Open Polymerization, Neema O. Msuya

Tanzania Journal of Engineering and Technology (TJET)

Polylactic acid (PLA) is a biodegradable and renewable alternative to non-biodegradable petrochemical-based polymers that is environmentally friendly and green. PLA can be made from a variety of agricultural wastes that contain sugars, such as sisal boles. This study aimed at analysing the possibility of producing PLA from lactic acid (LA) produced from sisal bole. A 2n factorial design was used to analyse the effects of temperature (160-180ºC), time (1-2 hrs) and tin octoate catalyst concentration (0.025-0.05%) on the PLA yield during polymerization. Minitab Version 20.2.0 was used to design the experiment and analyse the effects on the responses through ANOVA. …

Polymers And Composite Materials, Joshua P. Steimel

Pacific Open Texts

This text serves to cover in more detail polymer physics concepts and specifically how polymers respond from the atomistic to meter length scale. This text spans topics from polymerization chemistry, chain models, Flory-Huggins theory, viscosity, characterization techniques, self assembly, polymer dynamics, viscoelasticity, and mechanics of polymer and composite materials.

This work is licensed under a Creative Commons Attribution-NonCommerical-No Derivative Works 4.0 License.

Machine Learning Prediction Of Glass Transition Temperature Of Conjugated Polymers From Chemical Structure, Amirhadi Alesadi, Zhiqiang Cao, Zhaofan Li, Song Zhang, Haoyu Zhao, Xiaodan Gu, Wenjie Xia

Faculty Publications

Predicting the glass transition temperature (T_g) is of critical importance as it governs the thermomechanical performance of conjugated polymers (CPs). Here, we report a predictive modeling framework to predict T_g of CPs through the integration of machine learning (ML), molecular dynamics (MD) simulations, and experiments. With 154 T_g data collected, an ML model is developed by taking simplified “geometry” of six chemical building blocks as molecular features, where side-chain fraction, isolated rings, fused rings, and bridged rings features are identified as the dominant ones for T_g. MD simulations further unravel the fundamental roles …

Shape Memory Polymer Foaming With Tunable Interconnectivity Using Off-The-Shelf Foaming Components, Natalie Marie Petryk

Theses - ALL

The ability to tune pore structures of gas-blown polyurethane shape memory polymer (SMP) foams easily and safely could improve their outcomes as hemostatic dressings or tissue engineering scaffolds and overall commercialization efforts. Incorporating physical blowing agents into the polymer mix can be used to tune pore size and interconnectivity without altering foam chemistry. Enovate (HFC-254fa) is a commonly used physical blowing agent in gas-blown foams, but the Environmental Protection Agency (EPA) considers its use unacceptable because it is a hydrofluorocarbon that contributes to global warming. Here, off-the-shelf solvents accepted for use by the EPA, acetone, dimethyoxymethane (methylal), and methyl formate, …

Receptor-Doped Organic Transistors: Transducing Anion Binding From Mixed Ionic-Electronic Transport, Anthony Benasco

Dissertations

Organic semiconductors based on π-conjugated polymers show remarkable properties such as high tolerance to structural defects, low processing temperature requirements, biocompatibility, ease of fabrication, and tunable properties. Conjugated polymers integrated into device arrays can exhibit collective properties sensitive to minor perturbations in the surrounding media. However, these devices rely on serendipitous sensitivity to the analyte of interest, and strategies for specific detection remain a considerable change. There remains a compelling, global need for technologies to monitor phosphate due to its prevalence in agricultural runoff, leading to fish kills and economic decline for commercial and recreational fisheries. The strong hydration energies …

Reactive Thin Film Polymers And Thin Film Composite Membranes For The Rapid Screening Of Uranium Isotopes, Abenazer W. Darge

All Dissertations

Traditional radiochemistry approaches for the detection of trace-level alpha-emitting radioisotopes in water require lengthy offsite sample preparations and do not lend themselves to rapid quantification. Therefore, a novel platform is needed that combines onsite purification, concentration, and isotopic screening with a fieldable detection system. My dissertation research objective was to develop novel reactive thin polymer films and thin film composite membranes for the selective separation of uranium from environmental water followed by direct isotopic analysis by alpha spectroscopy. Chapter 1 reviews progress made on uranium separation from aqueous matrices and discusses methods used for the determination of isotopic composition.

Chapter …

Isolation And Production Of Tandem Collagen Binding Domain From Clostridial Collagenase Colg And Developments In C1q Reagent Production For Future Molecule Characterization Work, Stephanie Beitle

Chemical Engineering Undergraduate Honors Theses

This thesis covers a two part project: the production methods to create a double collagen binding domain molecule with a growth factor for wound healing applications and the development of a new in-house production method for isolating C1q from bovine blood. The wound healing molecule was created using transformation, sonication, and purification before being tested via electrophoresis SDS page and Western blots to confirm the molecule’s presence. The C1q in-house production method utilizes an ultrafiltration flow cell rather than dialysis at a critical point in the process, allowing for researchers to not only be able to use a single small …

Synthesis And Phase Transition Characterization Of Liquid Crystal Membranes With Slit-Like Pores, Isaac Hopwood

Chemical Engineering Undergraduate Honors Theses

Membranes with slit-like pores have been of interest for some time due to their ability to reject smaller particles than traditional cylindrical-pored membranes at the same fluid flux. However, using liquid crystals as a template for this sort of membrane has not been thoroughly investigated. In this study, the liquid crystal mixture of RM257 (2-Methyl-1,4-phenylene bis(4-(3-(acryloyloxy)propoxy)benzoate)) and 5CB (4-Cyano-4'-pentylbiphenyl) for the purpose of manufacturing membranes with slit-like pores, the phase transition behavior of this LC mixture at various mole fractions of RM257, and the impact of mole fraction of RM257 in the liquid crystal (LC) mixture and membrane manufacturing conditions …

Quantification Of Slit-Like Pores Through Using Liquid Crystals As A Template, Dominique Savage

Chemical Engineering Undergraduate Honors Theses

The purpose of this research is to manufacture a membrane with slit-like pores to achieve particle filtration. Slit-like pore membranes are preferred over conventional membranes with cylindrical pores since slit-like pores have two length scales that can be manipulated to better control cut off and flux through the membrane. This project focuses on manufacturing slit-like pore membranes through the use of two liquid crystals, 1,4-bis[4-(6-acryloyloxyhexyloxy)benzoyloxy]-2-methylbenzene (RM257) and 4-Cyano-4′-pentylbiphenyl (5CB). This method for making slit-like pores has not been widely investigated nor has the morphology of the membrane pores and mechanical properties of such a membrane been addressed. It was found …

Development Of Upconverting Films Containing Singlet Sink, Blake Mckay

Honors Theses

Upconversion is the conversion of light from a longer wavelength to a shorter wavelength. This technique has a wide range of applications in solar technology, bioimaging, drug delivery, and many other fields.¹ In this study, a three-part upconverting system was developed including a component termed singlet sink in order to increase upconversion efficiency. The components of this system included Palladium (II) Octaethylporphrin (PdOEP), pyrenebutanol, and 9-phenyl-10-(p-tolylethynyl)-anthracene (PTEA). A procedure was developed in order to create and process films containing these three materials dispersed in a poly(methyl methacrylate) (PMMA) matrix. Upconversion was analyzed in both solution and the …

Investigating The Effect Of Polymer Hydrogels On The Antimicrobial Properties Of Activated Carbon Through The Utilization Of Bacterial, Viral, And Parasitic Microorganisms, Zoe Gunter

Honors Theses

Activated carbon (AC) has long been utilized in biomedical applications due to its innate antimicrobial characteristics. However, little is understood about the mechanism of action that allows AC to prohibit the propagation of different pathogen species. To further ascertain these characteristics and how they affect the propagation of pathogens, procedures were designed with bacterial, viral, and parasitic agents which were utilized in conjunction with varying concentrations of polymer hydrogels to examine the antimicrobial efficacy of AC. The studies performed for this thesis were conducted employing coconut-based AC and Noveon^® AA-1 Polycarbophil USP or Carbopol^® 974P NF hydrogels which, …

Extractive Membranes For The Detection And Screening Of Waterborne Plutonium, James Foster

All Dissertations

The development of rapid screening tools for special nuclear materials remains a crucial focus for nonproliferation efforts. Traditional approaches for the analysis of trace-level Pu isotopes in water requires tedious and time-consuming sample preparation steps that do not lend well to expeditious screening. Therefore, a novel analytical method that combines both Pu concentration and source preparation into a single detection system would make for an invaluable tool for nuclear security applications. Extractive membranes absorbers can help to fulfill this role as they are capable of concentrating Pu to detectable limits while subsequently serving as alpha spectrometry sample sources. In Chapter …

Layered Epoxide-Amine/Boron Nitride/Graphene Nanocomposites For Enhanced Multifunctional Shielding, Alyssa J. Necaise

Honors Theses

The development of high-power electromagnetic wave sources in the modern era has the ability to interfere with aircraft electronics and cause localized heating – necessitating advanced materials for electromagnetic interference (EMI) and thermal shielding. Multifunctional nanoparticles dispersed within polymer matrices can combat these issues; however, the best way to combine thermally and electrically conductive species to maximize electromagnetic interference shielding and thermal shielding is undetermined. Multifunctional layered epoxide/amine nanocomposites were prepared from tetra and octafunctional epoxide monomers (TGDDM and SU-8), 4,4-DDS tetrafunctional amine curative, and 1 wt.% hexagonal boron nitride nanoplatelets and/or 1 wt.% graphene nanoplatelets to form monolayer and …

Novel Thermal Coating For High-Speed Airplanes, Abinash Satapathy, Lakshay Battu, Liam Watson, Nazanin Rajabi

Symposium of Student Scholars

In comparison to various other materials, Carbon Fiber, specifically Carbon Fiber Reinforced Polymers (CFRP), is pre-eminent amongst other materials for use on aeronautical systems. Due to its high specific strength (strength-to-weight ratio), CFRP is prominent for carrying heavy loads while maintaining a lightweight build. However, when influenced by heat resulting from air resistance, CFRP is known to undergo serious degradation that would significantly decrease the effectiveness of the polymers. To prevent this degradation and maintain the strength of the CFRP, thermal protective layers (TPLs) are designed to shield the CFRP from heat exposure. This research is focused on the examination …

The Effect Of Chitosan On The Surface Properties Of Cellulose-Based Paper Obtained From The Stem Of Flaxseed, E A. Egamberdiev, Y T. Ergashev, Kh Kh Khaydullaev, G Y. Akmalova, G R. Rakhmonberdiev

Technical science and innovation

This paper examines the effects of chitosan, starch, and polyvinyl alcohol (PVA) to improve the surface properties of cellulose-based paper obtained from local raw materials. The polymers are incorporated into the paper polythene by spraying. The results showed that the addition of chitosan to paper polythene, which is made of cellulose fibers, has an improvement in surface properties compared to the effect of other additives. The degree of exposure of starch coincided with the degree of exposure of chitosan, but it resulted in a decrease in the water absorption potential of the paper compared to chitosan at the same concentration. …

Tuning Electrochemical Interactions And Polymer Electrolyte Interfaces For Enhanced Organic Acid Separations Using Electrodeionization, Matthew Leo Jordan

LSU Doctoral Dissertations

Chemical separations are critical processes for chemical and industrial plants to purify and isolate products however current separation technologies, such as distillation, rely on energy intensive processes. Electrochemical separation processes, such as electrodialysis and electrodeionization, are an energy efficient alternative that are emerging as an alternative for thermal-based separations. Organic acids are weakly ionizable species and susceptible for purification from process streams using electrochemical processes. Recently the fermentation route has garnered greater attention as a means for producing value-added chemicals, such as organic acids, from a renewable feedstock and aiding the circular economy. Some of the challenges electrodialysis faces for …

The Greenest Solar Power? Life Cycle Assessment Of Foam-Based Flexible Floatovoltaics, Koami Soulemane Hayibo, Pierce Mayville, Joshua M. Pearce

Electrical and Computer Engineering Publications

This study presents a life cycle analysis (LCA) of a 10 MW foam-based floatovoltaics (FPV) plant installed on Lake Mead, Nevada, U.S. A material inventory of the flexible crystalline silicon (c-Si)-based module involved massing and determination of material composition of the module's encapsulation layers with ATR/FTR spectroscopy and electron microscopy. The LCA was performed using SimaPro and the results were interpreted in terms of cumulative energy demands, energy payback time, global warming potential, GHG emissions, and water footprint including negative values for reduced evaporation. A sensitivity analysis was performed on the lifetime of the modules and the foam-based racking. The …

4,6-O-Phenylethylidene Acetal Protected D-Glucosamine Carbamate-Based Gelators And Their Applications For Multi-Component Gels, Pooja Sharma, Guijun Wang

Chemistry & Biochemistry Faculty Publications

The self-assembly of carbohydrate-based low molecular weight gelators has led to useful advanced soft materials. The interactions of the gelators with various cations and anions are important in creating novel molecular architectures and expanding the scope of the small molecular gelators. In this study, a series of thirteen new C-2 carbamates of the 4,6-O-phenylethylidene acetalprotected D-glucosamine derivatives has been synthesized and characterized. These compounds are rationally designed from a common sugar template. All carbamates synthesized were found to be efficient gelators and three compounds are also hydrogelators. The resulting gels were characterized using optical microscopy, atomic force microscopy, …

Addressing Pfas Contamination In Blood Bank Supplies With Hydrogel Nanocomposite Sorbents, Anicah Lynn Smith, E. Molly Frazar, J. Zach Hilt

Posters-at-the-Capitol

Environmental pollutants continue to be a threat to global human health. Persistent contaminants, such as perfluoroalkyl substances (PFAS), have been linked to a multitude of adverse health effects such as cancerous tumors, increased blood cholesterol levels and liver damage. The dominant source of exposure to PFAS is through contaminated drinking water, and accumulation has been found to occur significantly in human blood serum. Thus, high-risk groups who are receiving frequent blood transfusions are exposed to these harmful chemicals in a dual fashion, which could prove detrimental. Traditional sorbents that display an affinity for PFAS include powdered activated carbon and clay. …

Molecular Modeling Of High-Performance Thermoset Polymer Matrix Composites For Aerospace Applications, Prathamesh P. Deshpande

Dissertations, Master's Theses and Master's Reports

The global efforts from major space agencies to transport humans to Mars will require a novel lightweight and ultra-high strength material for the spacecraft structure. Three decades of research with the carbon nanotubes (CNTs) have proved that the material can be an ideal candidate for the composite reinforcement if certain shortcomings are overcome. Also, the rapid development of the polymer resin industry has introduced a wide range of high-performance resins that show high compatibility with the graphitic surface of the CNTs. This research explores the computational design of these materials and evaluates their efficacy as the next generation of aerospace …

Reinforcement Of Elastomers By Reactive Ionic Surfactant, Nicole Vickerman

Williams Honors College, Honors Research Projects

Elastomers without cross-linking agents or fillers do not have the necessary properties for practical applications in the rubber industry. Elastomers must be reinforced with fillers and/or cross-linking agents to achieve the needs of physical and mechanical properties for commercial products. Sodium octyl 6-mercaptohexyl phosphate (SOMP) and sodium ethyl (6-mercaptohexyl) phosphate (SEMP) were used to investigate the influence of a reactive ionic surfactant and its influence on the physical properties of peroxide crosslinked styrene butadiene rubber (SBR). SEMP and SOMP were both found to be able to be grafted successfully on to the SBR chains within the rubber using extraction testing …