Polymer Chemistry Commons^™

Elucidation Of Optoelectronic Properties Of Pyrrolo[3,2-B]Pyrrole Chromophores, Ryan Faddis

Symposium of Student Scholars

Ryan Faddis Abstract

Elucidation of Optoelectric Properties of Pyrrolo[3,2-b]pyrrole Chromophores

Ryan Faddis and Graham S. Collier

Department of Chemistry and Biochemistry

Kennesaw State University

Derivatives of phenyl substituted pyrrolo[3,2-b]pyrroles have shown promise of being useful organic opto-electric compounds due to their advantageous tunability through careful synthetic design. Furthermore, one pot synthesis and readily accessible commercial reactants such as, aromatic amines and aldehydes, makes these molecules more favorable than other, more complex syntheses traditionally required for optically active organic molecules. Although relatively simple synthesize, more information from experimentation is needed to understand the optical properties of these species, and thus, a …

Lipoates As Building Blocks Of Macromolecules, Mojdeh Raeisi

Chemistry Theses and Dissertations

Since the discovery of Lipoic acid in the early 1950s, there have been several studies to further investigate properties and applications of this interesting, naturally occurring compound. In 1956, the dynamic nature of disulfide bonds in Lipoic acid was reported, which can exist through conversions of monomeric disulfide, polymeric disulfide, and reduced form (dithiol) from one to another under proper conditions. This dynamic nature and reducibility of disulfide bonds via thiol-disulfide exchange, opened doors to the use of Lipoic acid in drug delivery systems, especially for delivery to cancer cells that suffer from overexpression of glutathione – a thiol-bearing tripeptide …

Targeted Combination Therapy Of Nsclc Using Taxol And Fingolimod Loaded Nanoceria, Raghunath Narayanam

Electronic Theses & Dissertations

Among various types of cancers, lung cancer reports highest death rate and Non-Small cell lung cancer causes highest mortality in lung cancers. This is mainly due to the scarcity of treatment options and the available treatment shows numerous adverse effects. In the recent times, nanotechnology paved a new path for the diagnosis and therapy of cancer. In this study, we worked on a novel, multifunctional nanoceria (NC) platform loaded with two unique drugs taxol and fingolimod, which acts in their own ways providing synergic therapeutic effect. We hypothesized that the usage of the polyacrylic acid (PAA) coated nanoceria (PNC) increases …

Aerosol Vapor Synthesis Of Organic Processable Pedot Particles And Measuring Electric Conductivity Using A 3d Printed Probe Station, Yang Lu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Conducting polymers are organic semiconductors characterized by conjugated backbones (alternating single-double bonds) that enable mixed ionic-electronic conductivity. Their polymeric nature, tunable band structure and reversible redox capability have demonstrated fundamental advances in the fields ranging from electrochemical energy storage, sensing, to electro/photo catalysis and neuromorphic engineering. Conjugated backbones, the origin of all the unique physical and chemical properties associated with conducting polymers, prevent their solubility due to high lattice energy which hinders processing. Current solution utilizes a long-chain polymer (PSS) as dopants to render conducting polymer water dispersible (PEDOT:PSS). Nonetheless, PSS is highly acidic and hydrophilic limiting applicability with acid-incompatible …

Environment-Friendly Flame Retardants For Bio-Based Polyurethanes, Felipe Martins De Souza

Electronic Theses & Dissertations

Finding alternative ways to decrease the large consumption of non-renewable resources has been one of the greatest challenges faced by the industry and academia. The trend of using bio-renewable-based materials is an interesting alternative to tackle environmental issues as well as provide economically viable materials. In this work, carvone, an essential oil, was used to synthesize a bio-based polyol through a thiol-ene reaction. The chemical functions were analyzed through Fourier transformed infrared spectrum (FTIR), gel permeation chromatography (GPC), viscosity, and hydroxyl number, which confirmed the synthesis of carvone-based polyol. The latter was then physically blended with three different flame-retardants separately: …

End Group Modification Of Linear Dendritic Block Copolymers (Ldbcs), Chinwe Udemgba

Honors Theses

Linear dendritic block copolymers are amphiphilic molecules that consist of a dendritic hydrophilic portion and a linear hydrophobic portion. Its unique ability to self-assemble into spherical nanoaggregates while having the potential to uptake and transport both hydrophilic and hydrophobic drugs makes these polymers an item of interest in regard to the drug delivery field. The synthesis of polyamidoamine-polylactide linear dendritic block copolymers was designed to address the common issues in drug delivery systems, including problems in permeability, solubility, stability, specificity, and retention. Though this linear dendritic block copolymer has previously been synthesized in our lab with cationic amine surface functionalities, …

Synthesis And Self-Assembly Of Amphiphilic Block Copolymers For The Fabrication Of Non-Spherical Polymersomes, Tamuka Chidanguro

Dissertations

Polymersomes, also known as polymer vesicles, have gained a lot of interest over the past two decades. These hollow spherical systems are made via the self-assembly of amphiphilic block copolymers and have found use in a range of areas from drug delivery, to cellular models, to nanoreactors. Their hollow nature allows them to carry hydrophilic cargo in their inner compartment and hydrophobic cargo in their membrane. Over the last decade, increasing efforts have focused on controlling the morphology of polymersomes. Research has shown that polymersome morphology plays an important role for instance in drug delivery, where tubular or rod-like vesicles …

Design And Modeling Of Bioinspired Polyelectrolytes With Controlled Architectures For Gene Delivery Applications, Kelli Stockmal

Dissertations

This dissertation focuses on the development of a range of bioinspired polyelectrolytes with controlled architectures for gene and drug delivery applications. Glycans are ubiquitous in biological systems, and understanding the role of saccharide stereochemistry, as well as cationic charge, on polymer behavior in aqueous solution and the interactions with nucleic acids can provide insight into how synthetic polyelectrolytes can be used for non-viral gene delivery and other biological applications. The first chapter provides an introductory overview on how cationic polyelectrolytes can be used to aid the delivery of RNA for controlling gene expression in a variety of cell types, how …

Atomic Oxygen Resistant Low Earth Orbit Stable Polymer Matrix Composites Employing Phenylphosphine Oxide Epoxy-Amines, Witold Fuchs

Dissertations

Atomic oxygen (AO) attacks polymer matrix composites (PMC’s) on the surfaces of spacecraft in low earth orbit (LEO) and threatens safe spacecraft operation and service life. Incorporating phenylphosphine oxide (PPO) groups into polymer chains offers a self-regenerating method of protection from AO but remains poorly understood. Herein, epoxies containing PPO groups were synthesized with increasing concentrations of phosphorus [P] from 0 to 8 wt % to investigate their AO resistance. Measurements confirmed the exposure of these materials to AO produces a passivation phosphate (POx) layer on the surface of the sample and the efficacy of the resultant layer was directly …

Development Of Biomaterials For Drug Delivery, Raquel De Castro

Graduate Theses and Dissertations

Drug delivery systems (DDS) have highly evolved in the last decades with the development of hydrogels and nanoparticles. However, high systemic uptake, side effects, low bioavailability, and encapsulation efficiency continue to be a major hurdle faced by such DDSs.

Nanoparticles and hydrogels can be specifically designed for targeted DDSs to mitigate some of the problems. This dissertation aimed to design two DDSs for ocular drug delivery and one for cancer treatment. The first project sought to develop chitosan nanoparticles (Cs-NP) using PEGDA as a copolymer to encapsulate gentamicin (GtS) for ocular drug delivery. Cs-NPs contain positive charges that can interact …

A Conductivity Analysis Of A Newly Synthesized Poly(Ethylene Glycol) Methyl Ether Hydroxide Electrolyte, Sarah Marie Peterson

Honors Theses

This thesis investigates the synthesis and conductive properties of a Poly (ethylene glycol) methyl ether-based polymer electrolyte. The goal of the synthesis is to enhance the hydroxide ion conduction properties of the polymer with its cationic groups attached. The MePEG backbone contained seven ethylene glycol groups and was modified to substitute the hydroxide group in the MePEG with trimethylamine. In addition, the bromide added in the synthesis was exchanged for hydroxide ions to allow for the transportation of hydroxide ions in polymeric electrolytes that can be used in Anion Exchange Membrane Fuel Cells. The newly synthesized polymer was compared to …

Synthesis And Characterization Of Functiona Materials For 3d Printed Composites, Elizabeth Irene Reza

Open Access Theses & Dissertations

The following body of work encompasses the synThesis, upscaling, additive manufacturing, and characterization of microspheres as functional fillers incorporated into polymer syntactic foams. Synthesizing microspheres permits control over morphology, dispersion of particles, and size while the use of direct write manufacturing allowed for the controllability of filler orientation. Two different syntactic foams were developed from similar methodologies: (1) a silicone syntactic foam (2) epoxy syntactic foam. The silicone epoxy foam showed an increasing in damping and elastic modulus. The epoxy syntactic foams showed an enhanced thermal and electrical properties.

Synthesis And Conductivity Analysis Of A Methyl (Polyethylene Glycol) Comb Polymer, Olivia Fox

Honors Theses

The overall goal of work in this field is to improve materials for use in a variety of applications in fuel cell and battery production. This thesis specifically investigates the synthesis of two variations of a methyl (polyethylene glycol) comb polymer electrolyte (MePEG_nwhere n=7) to understand how the molecular structure of an ion-conducting polymer affects its electrochemical properties. The MePEG used in this synthesis contains seven ethylene glycol groups and was added to a poly (methylhydrosiloxane) comb polymer backbone. In the first sample, the polymer contained only the MePEG sidechain, and in the second sample, the polymer contained …

Effect Of Precise Control Of Crosslink Density On The Thermal, Mechanical, And Conductive Properties Of Covalently Crosslinked Ionene Networks, Alexander Thome

Honors College Theses

Ionic liquids (ILs), besides being well known as environmentally friendly solvents, have attracted attention for a wide variety of other applications, including gas separation, 3D-printing and electrochemical actuators. However, for many such applications, incorporation of the IL moiety into a polymeric material eliminates the use of mechanically unstable free ILs while maintaining many of their electrochemical benefits. Such polymers can take two basic forms: poly(ionic liquid)s are ion-containing polymers in which the IL group is attached pendant to the polymeric backbone, while ionenes are ion-containing polymers in which the IL group is anchored directly into the backbone of the repeating …

Thermal, Mechanical, And Rehealing Properties Of Cross-Linked Ionene Networks, Katelyn Lindenmeyer

Honors College Theses

Polymers which contain ionic liquid groups have numerous applications in a wide variety of fields. Past research from our group has shown that IL-containing polymers which exist in covalently crosslinked networks can exhibit good ionic conductivities despite the hindrance in polymer chain mobility and relaxation. In part one of this thesis, efforts to create ionic networks which have the capability of being rehealed after exposure to an external stimulus are discussed. Thermoreversible maleimide-furan chemistry was incorporated into an imidazolium-containing ionene network. Maleimide-terminated, imidazolium-containing monomers were coupled with furan-functionalized monomers, prepared from commercially available multifunctional acrylates. Thermal, mechanical and rheological characterization …

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 …

Application Of Zwitterions In Forward Osmosis: A Short Review, Yu-Hsuan Chiao, Arijit Sengupta, Micah Belle Marie Yap Ang, Shu-Ting Chen, Teow Yeit Haan, Jorge Almodovar, Wei-Song Hung, S. Ranil Wickramasinghe

Chemical Engineering Faculty Publications and Presentations

Forward osmosis (FO) is an important desalination method to produce potable water. It was also used to treat different wastewater streams, including industrial as well as municipal wastewater. Though FO is environmentally benign, energy intensive, and highly efficient; it still suffers from four types of fouling namely: organic fouling, inorganic scaling, biofouling and colloidal fouling or a combination of these types of fouling. Membrane fouling may require simple shear force and physical cleaning for sufficient recovery of membrane performance. Severe fouling may need chemical cleaning, especially when a slimy biofilm or severe microbial colony is formed. Modification of FO membrane …

Development Of Engineered Soil Surrogates For Modeling Natural Soil Sorption Behavior, Ghada Yehia Abdalla

LSU Doctoral Dissertations

The land produces more than 95% of the global food supply, and with a continuously growing population, we need to optimize the use of the available agricultural land. Soil organic matter (SOM) is an essential component of soils, especially concerning their fertility and sorption behavior. The chemical composition of the SOM consists of lipids, lignin, and cellulose. However, the heterogeneous and complex nature of SOM, and real soils, makes their study challenging and introduces uncontrollable factors.

Therefore, structural mimics of natural soils with increasing complexity representing the real soil functionality were synthesized and evaluated for bulk properties related to their …