Chemistry Commons^™

Combinatorial Synthesis Of Protein-Polymer Conjugates By Post-Polymerization Modification Of Poly(Pentafluorophenyl Acrylate)S, Emily W. Kish, Thatcher M. Lee, Alexis M. Ziemba, Ama Boamah, Bianca Figueroa, Margherita Piccardi, Carey E. Dougan, Sarah J. Moore, Maren E. Buck

Chemistry: Faculty Publications

Combinatorial methods for preparing polymeric biomaterials enable the rapid identification of materials useful for many applications in science, medicine, and engineering. In the work described here, we demonstrate that side-chain reactive polymers can be used as templates for the rapid preparation of a small library of diversely functionalized protein–polymer conjugates. The activated ester polymer poly(pentafluorophenyl acrylate) (PPFPA) was modified postpolymerization with substoichiometric equivalents of three hydrophilic primary amines to yield a library of amphiphilic, side-chain reactive copolymers. These copolymers were then conjugated to two receptor-targeting proteins, holotransferrin (hTF) and an engineered fibronectin-based protein (Fn3), through amine-activated ester coupling. We investigated …

Identification Of Modified Polymer End Groups For Correlations To Physical Properties, Tj Sacco

Williams Honors College, Honors Research Projects

Plastic has become the primary material for containers in both industrial and commercial fields. Plastics are the optimal choice since they have many physical properties that make them ideal candidates: durability, heat resistance, chemical stability, as well as their inexpensive production cost. Nowadays, the desire for more versatile plastics with strength, flexibility, hydrophobicity, and biodegradability has grown; however, concerns for plastic use have started to rise as well. The overuse of plastics poses a threat to the environment and people’s health: plastics are hard to break down completely which results in the formation of micro(nano)plastics (MNPs). In attempts to circumvent …

Sustainable Polyaddition Path To Polyesters Via Catalytic Homocoupling Of Renewable Dicrotonate Monomers, Shabbir Asif, Mahsa Saeidi, Braden D. Pickle, Nicholas J. Tabbah, Michael L. Mcgraw

Chemistry & Biochemistry Faculty Publications and Presentations

The development of biorenewable polyhydroxyalkanoate (PHA) chemistry has generated interest in crotonate-based monomers as versatile building blocks. Crotonates can be obtained through the pyrolysis of PHAs, offering both a sustainable end-of-life pathway for PHAs and a renewable route to crotonate monomers. This study presents a new polyaddition-type step-growth polymerization of dicrotonates in which alkene-functionalized polyesters are synthesized using potassium tert-butoxide as a simple base catalyst. The reaction proceeds rapidly at room temperature, achieving >99% conversion within seconds and requiring no byproduct removal. The properties of the resulting polyesters can be tuned via the choice of bridging diol, and the materials …

Photo-Enhanced Output In Memdiode Devices Based On Hybrid Materials Open Access, Jacob Lee, Prabir Patra, Judy Fan

Physics Faculty Research

The discovery of photo-enhanced outputs in the fabricated memdiodes based on metal halide-embedded polymeric hybrid composites has meaningful and practical implications. The two-terminal devices exhibit typical rectifying characteristics, similar to a standard pn junction diode, with unusual photo-enhanced charge transportation and hysteresis behaviors. The MDs consist of an active layer of blended organic–inorganic hybrid material [a mixture of CuCl2 and polyethylene glycol (PEG)] deposited on a layer of pure polymer (polymethyl methacrylate) and, in turn, on a rigid substrate (ITO glass or Si wafer). It is found that the photoinduced current increases hundreds of times in magnitude on the ITO …

Biobased Acrylate Composites With Enhanced Strength For Additive Manufacturing, Nicole Wagner, Joseph Mcwherter

Engineering Faculty Articles and Research

With the expanding use of polymers in additive manufacturing, sustainable resins for use in vat photopolymerization are required to reduce their environmental impact. One promising approach to achieve this is to incorporate biobased fillers that replace the acrylates in photopolymer resins as ‘green’ alternatives. In this study, photopolymer composites consisting of a methacrylate resin with varying calcium carbonate powder content between 0 and 50 wt.% were investigated. A digital light processing technique was used to fabricate tensile test specimens for mechanical testing. Good printability, dimensional accuracy, and good interlayer adhesion were observed for composite resin formulations that incorporated calcium carbonate …

The Study Of Biomass Based Polymers And Cyclic Polymers, Yishayah Bension

Theses and Dissertations

Plastics have become an integral part of everyday life, from household care to aerospace applications, polymers are involved in every industry. Most of these polymeric materials are derived from petroleum feedstocks which have deleterious effects on our environment. The production of petrochemicals has led to an increase in greenhouse gases and microplastic pollution which have accelerated climate change. My research focuses on utilizing existing biomasses to improve the plastic economy’s circularity. This work develops new materials from bio-based polymers such as lignin and soybean oil. Raw lignin suffers from inherently weak mechanical properties, poor solubility, processability, and molecular structure ambiguity. …

Synthetic Approaches Of Carbohydrate Based Self-Assembling Systems, Guijun Wang, Anji Chen, Pramod Aryal, Jonathan Bietsch

Chemistry & Biochemistry Faculty Publications

Carbohydrate-based self-assembling systems are essential for the formation of advanced biocompatible materials via a bottom-up approach. The self-assembling of sugar-based small molecules has applications encompassing many research fields and has been studied extensively. In this focused review, we will discuss the synthetic approaches for carbohydrate-based self-assembling (SA) systems, the mechanisms of the assembly, as well as the main properties and applications. This review will mainly cover recent publications in the last four years from January 2020 to December 2023. We will essentially focus on small molecule self-assembly, excluding polymer-based systems, which include various derivatives of monosaccharides, disaccharides, and oligosaccharides. Glycolipids, …

B(C₆F₅)₃ Co-Catalyst Promotes Unconventional Halide Abstraction From Grubbs I To Enhance Reactivity And Limit Decomposition, Austin W. Medley, Diya Patel, Calvin Utne, Trandon A. Bender

Chemistry & Biochemistry Faculty Publications

Ruthenium based Grubbs metathesis has become a commonplace reaction for synthetic chemists. Development of new generations of catalysts evolving from Grubbs I (GI) have led to greater stability, functional group compatibility, and superior reactivities. However, these advancements lead to increased costs. To this end, we report here how the addition of the commercially available tris(pentafluorophenyl)borane Lewis acid, which has become a common place catalyst in its own right, leads to enhanced reactivity of GI. Moreover, the increased reactivity arises via halide abstraction rather than traditional phosphine dissociation, providing ring-opening metathesis polymerization products that are divergent from those synthesized without the …

Nanoparticles And The Environment: Biopolymer Grafted Cellulose And Screen-Printed Carbon Nanotube Composites, Dominique Henry Porcincula

Master's Theses

A host of environmental issues will define the state of the environment in the 21^st century, with plastic pollution and water shortages among them. While solutions to these problems require large-scale, multipronged solutions, one way we can address them is through material innovation and the use of nanoparticles.

In the first project, we address the issue of plastic pollution by creating nanocomposites of biodegradable polymers (PLA and PCL) with cellulose nanofibrils. Here, PLA and PCL are grafted from the surface of cellulose nanofibrils via ring-opening polymerization of cyclic ester monomers. Polymer-grafted cellulose (PGC) is characterized with structural analysis, solubility …

Depolymerizing Self-Immolative Polymeric Lanthanide Chelates For Vascular Imaging., Eric Grolman, Quinton E A Sirianni, Joy Dunmore-Buyze, Charmainne Cruje, Maria Drangova, Elizabeth R Gillies

Chemistry Publications

Medical imaging is widely used clinically and in research to understand disease progression and monitor responses to therapies. Vascular imaging enables the study of vascular disease and therapy, but exogenous contrast agents are generally needed to distinguish the vasculature from surrounding soft tissues. Lanthanide-based agents are commonly employed in MRI, but are also of growing interest for micro-CT, as the position of their k-edges allows them to provide enhanced contrast and also to be employed in dual-energy micro-CT, a technique that can distinguish contrast-enhanced blood vessels from tissues such as bone. Small molecule Gd3+ chelates are available, but are excreted …

Self-Immolative Hydrogels With Stimulus-Mediated On-Off Degradation., Jue Gong, Aneta Borecki, Elizabeth R Gillies

Chemistry Publications

Hydrogels are of interest for a wide range of applications from sensors to drug delivery and tissue engineering. Self-immolative polymers, which depolymerize from end-to-end following a single backbone or end-cap cleavage, offer advantages such as amplification of the stimulus-mediated cleavage event through a cascade degradation process. It is also possible to change the active stimulus by changing only a single end-cap or linker unit. However, there are very few examples of self-immolative polymer hydrogels, and the reported examples exhibited relatively poor stability in their nontriggered state or slow degradation after triggering. Described here is the preparation of hydrogels composed of …

Atom Economical Reactions Of Terpenoids And Post-Consumer Plastics With Sulfur, Charini Maladeniya

All Dissertations

The production of Ordinary Portland Cement (OPC) and its uses have a complicated environmental impact, which is influenced by infrastructure development and building operations as well as CO₂ emissions, which account for 7% of all worldwide CO₂ emissions. Due to the increasing population, production is still ongoing. The search for cement and construction materials produced with zero to low CO₂ emissions is therefore continuous. Finding recyclable, CO₂ gas-free biocomposites with high sulfur content that can rival the mechanical properties of popular building supplies like Portland cement is the primary objective of the research discussed in this …

Engineering Of Bio-Based And Synthetic Polymers: Synthesis And Application In Superabsorbent Materials And Antibacterial Agents, Jihyeon Hwang

Theses and Dissertations

A polymer consists of a large number of monomer units, which can be obtained naturally or via a chemical process called polymerization. Polymers are important materials that are used in our daily life. Life would not be possible without these polymers, either from plant biomass or petroleum-derived synthetic polymers. The substitution of petroleum-derived to biomass-based polymers has been highlighted to mitigate adverse environmental impact. However, the use of bio-based polymers is still a significant challenge for more demanding applications. In this dissertation work, the engineering of both bio-based and synthetic polymers and their properties are investigated.

In Chapter 1, the …

Design And Fabrication Of Single-Chain Nanoparticles, Vitrimers, Bottlebrush And Comb Polymers, Logan Dugas

Dissertations

The introduction of novel dynamic exchange chemistries into polymer chains and networks has shown great potential of giving next generation polymeric materials. Within the scope of this thesis, dynamic chemistry is employed to realize single-chain nanoparticles, vitrimer networks, bottlebrush and comb polymers. CHAPTER I provides a broad introduction to the topics at hand, focusing upon the techniques utilized to achieve such materials with relevant literature and understanding of the techniques and architectures explored. CHAPTER II focuses upon the synthesis of single-chain nanoparticles via a copolymerization of polyisobutylene macromonomers with norbornene monomers equipped with pendant anthracene moieties. Through this work, the …

Synthesis And Characterization Of Polymer Grafted Nanoparticles, Eric Gerald Ruzicka

Theses and Dissertations

This dissertation focuses on the design, synthesis, and characterization of well controlled interfaces on nanoparticle surfaces. Reversible addition-fragmentation chain transfer (RAFT) polymerization was used to synthesize block copolymers and polymer grafted silica nanoparticles (PGNs) with precise control over molecular weight, graft density, and architectures.

In the first chapter, polymer molecular weights were determined through diffusion ordered spectroscopy NMR (DOSY NMR) as an alternative to size exclusion chromatography (SEC). Polymer standards of known molecular weight were analyzed through DOSY to obtain their respective diffusion coefficients. A calibration curve was generated correlating diffusion coefficients with polymer molecular weights. The reliability of the …

Enhancing The Forensic Comparison Process Of Common Trace Materials Through The Development Of Practical And Systematic Methods, Meghan Nicole Prusinowski

Graduate Theses, Dissertations, and Problem Reports (ETD)

An ongoing advancement in forensic trace evidence has driven the development of new and objective methods for comparing various materials. While many standard guides have been published for use in trace laboratories, different areas require a more comprehensive understanding of error rates and an urgent need for harmonizing methods of examination and interpretation. Two critical areas are the forensic examination of physical fits and the comparison of spectral data, which depend highly on the examiner’s judgment.

The long-term goal of this study is to advance and modernize the comparative process of physical fit examinations and spectral interpretation. This goal is …

Synthesis And Processing Of Polymeric Materials For Hydrogen Storage, Dominic Adrewie

Theses and Dissertations

Hydrogen is one of the most promising alternatives and clean fuel sources, but it has faced several hurdles due to storage and transportation issues. Several methods have been proposed, developed, and are being improved. Key among these is the use of polymers as safe hydrogen storage media.

This work investigated the polymerization of methyl vinyl ketone using different concentrations 2,2’-Azobis(2-methylpropionitrile) as the initiator in a free radical polymerization mechanism. There was a subsequent analysis of the effect of the initiator concentration on the conversion rate and the molecular weight of the polymers produced with the help of Gel permeation chromatography. …

Comprehensive Review Of Polymer And Polymer Gel Treatments For Natural Gas-Related Conformance Control, Ali Al Brahim, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Conformance problems often exist in natural gas-related activities, resulting in excessive water production from natural gas production wells and/or excessive natural gas production from oil production wells. Several mechanical and chemical solutions were reported in the literature to mitigate the conformance problems. Among the chemical solutions, two classes of materials, namely polymer gels and water-soluble polymers, have been mostly reported. These systems have been mainly reviewed in several studies for their applications as water shutoff treatments for oil production wells. Natural gas production wells exhibit different characteristics and have different properties which could impact the performance of the chemical solutions. …

Sustainable Polymers: Upcycling Poly(Vinyl Chloride) And Mimicking Low Density Polyethylene, Ian Baxter

Theses and Dissertations

In this research, increasing the sustainability of polymers was investigated through two main methods. The upcycling of poly(vinyl chloride) and the creation of polymer mimics to create degradable low-density polyethylene. In the first chapter, an overview of the sustainability issues of polymers is presented and approaches are described on how their sustainability may be increased through the upcycling of polymers or the synthesis of degradable polymers that mimic the properties of petrol-based polymers.

Chapter 2 contains the progress on the upcycling of PVC using high oleic soybean oil. Soybean oil can soften PVC making it less brittle than pure PVC. …

Covalent Attachment Of Tadf Chromophores To Thermally Stable Poly(Arylene Ether)S, Samuel Farrar

Browse all Theses and Dissertations

The covalent attachment of a blue emitting, benzothiazole based TADF chromophore into poly(arylene ether) backbone polymers was explored. A benzothiazole derivative, 2-(2,4-difluorophenyl)-benzothiazole (2,4-diF-BTZ), was synthesized to form the electrophilic component of the host polymer. Two polymers were synthesized to have chromophore incorporated, using 2,4-diFBTZ and 4,4-dihydroxydiphenyl ether (DPE) or 4,4’-biphenol (BP). The chromophore was covalently incorporated at a 10% molar ratio into the polymer backbone by copolymerization with 2,4-diF-BTZ and BP, utilizing nucleophilic aromatic substitution (NAS). Structural characterization was provided via NMR spectroscopy and GC/MS analysis. The polymer syntheses provided high molecular weight materials that were able to be cast …

Gene Vectors With Fluorescence Tracking Capabilities, Sophia Despina Angelopoulos

Browse all Theses and Dissertations

This project focuses on the optimization of benzothiazole-based chromophores to utilize them as fluorescent tags functionalized onto stimuli-responsive, or “smart,” polymers as non-viral gene delivery vectors for gene therapy applications. Blue-fluorescent emissive chromophores will allow tracking capabilities for the transfection pathway of the vector to be monitored as it delivers the DNA payload within intercellular space. The most appropriate chromophore must be covalently bound to a free amine within the vector, which is accomplished through NAS chemistry from fluorophenyl-benzothiazoles (F-BTZ-CBz) derivatives to amidated hyperbranched poly(ethyleneimine)(HPEI-IBAm0.61). HPEI is considered to be a synthetic polycation, which promotes tunable solubility through characteristics of …

Teaching An Old Dog New Tricks: Synthesis And Applications Of Novel Polybenzimidazole (Pbi) Membranes, Laura Ann Murdock

Theses and Dissertations

Polybenzimidazoles (PBIs) represent a class of performance polymers that display exceptional thermal and oxidative stability. For almost thirty years, PBI membranes have been investigated as promising candidates for next-generation alternative energy devices, including high temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) and vanadium redox flow batteries (VRBs). Issues with the production of PBI membranes arise from their inherent low solubility in organic solvents. Thus, conventional approaches typically yield membranes that have limited molecular weight and generate significant waste in preparation, due to the large quantity of solvent required to dissolve PBIs for membrane casting.

Presented herein is the development of …

Design Of Antioxidant Monomer, Augustine Osilamah Yusuf

Masters Theses & Specialist Projects

Reactive oxygen species such as hydrogen peroxide are present at the sites of inflammation in the body. Degradable polymeric nanoparticles have shown great promise in a range of biomedical applications which include preferential delivery of therapeutics to such inflamed sites. We are working towards a new class of materials expected to have tunable degradation rates in the presence of hydrogen peroxide. These new materials consist of three parts: degradable linkages, antioxidant groups, and unreactive filler monomers such as methylmethacrylate. We have synthesized a polymerization initiator with a degradable linkage, and we have shown that using this initiator to synthesize another …

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 …

Degradation Of Natural And Synthetic Fibers In Various Aqueous Environments, Jaylin Bryant

Honors Scholars Collaborative Projects

Fabrics are one variant of polymers, macromolecules that form the foundation of our society. They consist of small subunits called monomers, which are covalently bonded together and layered over each other through intermolecular attractions. There are natural fabrics, such as cotton and silk, and synthetic fabrics like polyester and rayon. Scientists in forensic taphonomy study postmortem changes made to human remains, which can also include clothes found at the scene. In this study, the degradation rates of four white fabrics (cotton, polyester, rayon, and silk) were observed in various aqueous environments (pure, chlorinated, sea, and lake) in order to observe …

Advances In Polymer Based Friedlander Quinoline Synthesis, Rajendra Patil, Jagdish Chavan, Shivnath Patel, Anil Beldar

Turkish Journal of Chemistry

Nitrogen containing heterocyclic compounds has acquired their remarkable and distinct place in the wide area of organic synthesis due to the broad range of applications. Among them, quinoline motifs have attracted researchers in the synthetic chemistry because of its presence in the large number of pharmacologically active compounds. Different methods for synthesis of quinoline derivatives are reported, among them the Friedlander synthesis have provided comparatively more efficient approach. Many of the reported conventional Friedlander methodologies have some problems such as difficult product isolation procedures, poor yields and use of expensive catalysts, etc. Recently, polymer or solid supported synthetic approaches have …

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 …

Fabrication, Characterization And Environmental Monitoring Of Polymer-Based Materials For Biomedical And Structural Applications, Mousumi Bose

Doctoral Dissertations

"Polymers are versatile materials utilized for variety of applications. In biomedical field, luminescence quenching based optical oxygen sensors encapsulated in polymeric substances are gaining attention for early detection of surface wounds associated with tissue oxygen. A simple and low-cost fabrication technique was developed to produce sensor arrays for continuous two-dimensional oxygen tension measurement. Sensor patch along with smart phone-based readout technique is being evaluated as a smart bandage.

The environmental concerns and limited petroleum supply demand for replacing petroleum-based polymers with renewable bio-based sources while maintaining comparable properties. A sustainable and green approach was adopted to synthesize soy polyol-derived rigid …

Functionalized Materials From Atom Transfer Radical Processes, Sean Fischer

Electronic Theses and Dissertations

This work is focused on the synthesis, characterization, and application of functionalized materials prepared from atom transfer radical processes. Atom transfer radical processes encompass both atom transfer radical addition (ATRA) and polymerization (ATRP) reactions, both of which are catalyzed by ppm amounts of copper complexes. The synthetic efforts of ATRA include increasing adduct selectivity through optimization of reaction conditions to generate small molecules in high to moderate yields. ATRA provides retention of the halogen moiety, which is an attractive functional group that can be further modified with other transformations. Specifically, the copper-catalyzed azide-alkyne [3+2] cycloaddition (CuAAC) allows for the realization …

Control Of Corrosion On Ss316l Using Surface Initiated Polymers, Alexander Rupprecht

Electronic Theses and Dissertations

Pitting corrosion is arguably one of the most destructive and dangerous forms of corrosion, resulting in damage to structures, the environment, and public health. In addition, damage caused to structures such as bridges, pipelines, and boats, corrosion also has a profound effect on the biomedical community. Implanted metallic devices (i.e., vascular stents and artificial joints) are prone to pitting corrosion caused by aggressive ions present in extracellular fluid. To provide a corrosion-resistant surface on SS316L, films of poly(styrene), poly(methyl acrylate), and poly(methyl methacrylate) were formed using surface-initiated atom transfer radical polymerization (SI-ATRP). The resulting hydrophobic polymer films had a fractional …