Polymer Chemistry Commons^™

Formulation Development Of A Polymer-Drug Matrix With A Controlled Release Profile For The Treatment Of Glaucoma, Eric W. Tsoi

Master's Theses

Glaucoma is the leading cause of blindness in the United States accounting for 9-12% of all cases of blindness. Currently, the front line treatment for glaucoma are prostaglandins that may have to be taken up to several times a day. Even with proper treatment, roughly 11% of the patients using the treatment are non-compliant and lose their vision. In this project, ForSight Laboratories has developed a pharmaceutical drug delivering implant with the capability of sustaining long-term release of a prostaglandin as a new way to treat the condition. This project reports the product development of a polymer drug matrix with …

Phase Behavior And Rheology Of Latex, Thickener, Surfactant Mixtures And Liquid Crystal Based Compositions For Printing High-Efficiency Flexible Electronics, Franceska Anna Santos

Master's Theses

This project consists of two parts. One area of focus in the first part is understanding the interactions between a non-ionic, block copolymer type dispersant and hydrophobically-modified, ethoxylated urethane (HEUR) associative thickeners in water. The dispersant was mixed at various concentrations (0-2% by weight) with HEUR thickeners at 1% by weight concentration in the aqueous medium. This study is an integral part of our attempts to determine mechanisms of viscosity drop when colorant dispersions are added to latex tint base formulations thickened with associative thickeners. One of the HEUR thickeners is a product that has been available for over three …

Nanoparticles And Polymer Crystallization Kinetics In Hybrid Electronic Devices, Taylor William Wagner

Master's Theses

Conjugated semi-conducting polymers have become well known for their potential applications in hybrid electronic devices like solar cells, LEDs, and organic displays. These hybrid devices also contain inorganic nanoparticles, which complement the polymer when they are combined into the same layer. Control over the conformation and crystallinity of the polymer is critical for device performance, yet not much is known about the effect that these nanoparticles have on the polymer. Here, zinc oxide nanowire was surface modified with mono-substituted-carboxylic acid tetraphenylporphyrin and dodecanethiol, and introduced to poly(3-hexyl thiophene) in solution. The electron transfer, kinetics, and thermodynamics of this system were …

Morphology And Conformation Of Polythiophene Derivatives In Anisotropic Core-Shell Nanocomposites And Solution, Neil Redeker

Master's Theses

Conjugated semiconducting polymers have garnered substantial interest in recent years due to the potential for use in various applications, particularly in the field of electronic devices such as photovoltaic cells and light emitting diodes. Conjugated polymers offer numerous advantages in these applications, including low cost and high flexibility, but electronic devices based on these materials are currently limited by poor performance. Because of these limitations, increased focus has been placed on improving conjugated polymers for use in commercially viable products. Here, a novel core shell hybrid nanocomposite based on anisotropic zinc oxide nanowires and a side-chain functionalized polythiophene is reported. …

Design And Synthesis Of Flexible And Functional Polybenzoxazine Thin Films, Austin David Baranek

Dissertations

Polybenzoxazines offer the unique ability to incorporate a variety of properties and functionality into a single polymer network through simple synthetic techniques. However, within benzoxazine materials exist certain drawbacks of which brittleness is the primary issue when exploring thin film applications. This brittleness leads to poor mechanical stability and would reduce the lifetime of any device sought after. It is, however, through the simplistic nature of the benzoxazine monomer synthesis that the mechanical stability could be addressed chemically, avoiding the complications of using rubber toughening agents or plasticizers. The monomer synthesis offers tailorability of both the phenol and amine to …

Synthesis And Characterization Of A New Cyano-Substituted Tris(Pyrazolyl)Borate And Its Thallium(I) Complex, Bozumeh Som

Electronic Theses and Dissertations

A new cyanoscorpionate - tris(4-cyano-3,5-diphenylpyrazolyl)borate (Tp^Ph2,4CN) has been synthesized and characterized. The thallium complex of this ligand TlTp^Ph2,4CN has also been prepared and characterized by FT-IR, ¹H NMR, and single-crystal X-ray-diffraction. The complex TlTp^Ph2,4CN crystalized in the monoclinic space group C2/c with unit cell a = 14.6697(10) Å, b = 13.9493(10) Å, c = 19.3347(12) Å, and b= 91.761(2)°. Structural comparison of TlTp^Ph2,4CN with analogous complexes demonstrated the effects of both steric and electron-withdrawing substituents on coordination geometry and the electronic properties of the metal ion. There were short contacts between the cyano groups …

Poly (N-Isopropylacrylamide) Microgel-Based Etalons And Etalon Arrays For Determining The Molecular Weight Of Polymers In Solution, Molla R. Islam, Michael J. Serpe

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Positively and/or negatively charged poly (N-isopropylacrylamide)-based microgels were deposited on a single substrate and isolated regions of Au overlayers were deposited on top of the microgels. Each spatially isolated Au overlayer region had a different thickness to make an etalon array.We found that areas with a thin Au overlayer (5 nm) responded to a range of polymer molecular weights (MW), while areas with a thick overlayer (35 nm) can only respond to low molecular weight polyelectrolytes. By comparing the optical responses of the device’s individual array elements, a good approximation of the polyelectrolyteMWin solution can be made.

Development Of Biodegradable And Stimuli-Responsive Macromolescules And Their Assemblies, Ali Nazemi

Electronic Thesis and Dissertation Repository

Polymersomes are potentially multifunctional soft materials constructed by the self-assembly of amphiphilic block copolymers in aqueous medium. While much research has focused on controlling the assembly and encapsulation properties of polymersomes, their surface functionalization has been relatively unexplored. This is important because it plays a critical role in determining their properties such as toxicity and biodistribution behavior. The work described in this thesis involves the development of a biocompatible and biodegradable polymersome systems based on poly(ethylene oxide)-b-polycaprolactone (PEO-PCL) block copolymers with azide surface groups as a novel scaffold for various biomedical applications. The surface functionalization of these polymersomes …

Synthesis Of Environmentally-Friendly Polyurethane Dispersions Based On Soybean Oil- Derived Polyols And Their Applications In Advanced Water-Based And Uv-Cure Coatings, Senthikumar Rengasamy

Master's Theses and Doctoral Dissertations

Polyurethane dispersions (PUD) have established themselves as most versatile polymeric binder in coating, adhesive, sealant, and elastomer industries. Like any other polymers, PUDs also have certain limitations, such as hydrolytic stability, water resistance, and oil resistance. In order to develop these properties, two different polyol families were synthesized. The first polyol can be used in ambient curable systems, and the second can be utilized in ultraviolet radiation cure coatings. For ambient curable systems polyether chemistry based soy-polyol was developed from epoxidized soy fatty acid methyl ester (ESFAME). The cationic ring opening of oxirane oxygen groups from ESFAME resulted in polyol …

Influence Of Cholesterol And Bilayer Asymmetry On Membrane Protein Distribution In Polymer-Tethered Raft-Mimicking Lipid Membranes, Noor Fueza Hussain

Open Access Dissertations

It is now widely recognized that lipid rafts, which are membrane domains enriched in cholesterol (CHOL) and sphingolipids (SL), play a significant functional role in the plasma membrane. Raft domains particularly affect membrane functionality by causing sequestering of membrane proteins. Underlying mechanisms of raft-associated membrane protein sequestration remain elusive, due to the complexity, transient nature, and small size of raft domains in cellular membranes. To address these challenges, this dissertation unveils the relationship between lipid raft composition and membrane protein sequestration and function using raft-mimicking model membrane mixtures comprised of coexisting liquid-ordered (lo) and liquid-disordered (ld) domains with reconstituted membrane …

The Effect Of Composition On The Linear And Nonlinear Mechanical Properties Of Particulate Filled Elastomers, Oluwaseyi Ogebule

Open Access Dissertations

Engineering elastomers are materials capable of undergoing large deformation upon load application and recovering upon load removal. From car tires to building vibration isolator systems, elastomers are the most versatile of engineering materials. The inclusion of particulate fillers into elastomers enhances their mechanical properties (modulus, tensile strength, toughness, tear resistance, etc) thereby extending their applicability to more demanding functions. The automotive, healthcare, construction, adhesives and consumer products are some of the many industries that produce finished goods containing elastomeric parts.

Despite the various concepts on reinforcement in filled elastomers, a complete understanding of their linear viscoelastic properties and the nonlinear …

Development Of Quantitative Ft- Ir Methods For Analyzing The Cure Kinetics Of Epoxy Resins, Sang Ha Son

Open Access Dissertations

Epoxy thermosets are important engineering materials with applications in coating, adhesives, packaging and as structural components in a variety of advanced engineering products. The ultimate performance of polymer critically depends upon the details of the cure chemistry used to produce the thermoset. In order to better understand and monitor the cure chemistry, quantitative analysis of the FT-IR response has been developed for describing the epoxy-amine curing reaction as well as monitoring the hydrogen bonding that occurs in these systems The FT-IR analysis includes (i) quantitative deconvolution of complex peaks into individual spectral contributions, (ii) peak identification via DFT analysis and …

Use Of Thermodynamic Models For Optimizing Fuel Treatment Processes, Shawn Pj Kirby, Andrew Guenthner

STAR Program Research Presentations

Dyes are often added to fuels for tax purposes, but they cause degradation of the fuels. It would be advantageous to remove the dyes prior to their use in critical aerospace applications. Current technologies vary in the efficiency with which they can remove unwanted dyes from fuel sources. We have used Hansen Solubility Parameters to develop an “ideal solvent” that can be used to extract these dyes from fuel. This will also be applied to removal of sulfur compounds from fuels. Sulfur compounds in fuels create sulfates during combustion, which in turn react with water to make sulfuric acid. Sulfuric …

Neutron Scintillation Detectors Based On Polymers Containing Lithium-6 For Radiation Portal Monitor Applications, Andrew Neil Mabe

Doctoral Dissertations

The work presented herein describes an investigation of four main types of thin film polymer scintillators containing ⁶Li [lithium-6] for neutron detection: polystyrene containing ⁶LiF [lithium-6 fluoride] and a preblended fluor mixture comprising 2,5-diphenyloxazole and 1,4-bis(5-phenyloxazol-2-yl)benzene; poly(styrene-co-lithium maleate) containing salicylic acid; poly[styrene-co-lithium maleate-co-2-phenyl-5-(4-vinylphenyl)oxazole]; and poly(styrene-co-lithium 4-vinylbenzoate). A variety of chemical and physical characterizations as well as optical and scintillation characterizations were performed to guide the development of optimized compositions of each type of polymer film. The scintillation performances of optimized compositions of each type of polymer film were calibrated using …

Development Of Colloid Displacement Lithography Platforms For Sensor Applications, Mahesh Thugu

Masters Theses & Specialist Projects

In this work, Poly (diallyldimethylammonium) chloride - (PDDA) was used as a base layer for developing colloid displacement lithography platforms for sensor applications. Previous work shows that glass coated with PDDA and exposed to gold acts as a good platform for colloid displacement lithography. However, for actual sensor applications, electrical isolation of individual sensor sections must be achieved. This is attempted by laying down a 40 μm stripe of PDDA on a cleaned substrate and coating that stripe with gold colloid. The size of 40 μm or less in width is set as the target to fit within the scan …

In Situ Quenching And Post-Polymerization Modification Of Telechelic Polyisobutylene, Todd Raymond Hartlage

Dissertations

Polyisobutylene (PIB) is a saturated hydrocarbon elastomer that can only be produced by cationic polymerization. The water-initiated, chain transfer controlled synthesis conducted on an industrial scale produces monofunctional PIB with mixed olefin end groups. Living cationic techniques produce mono- and di-functional telechelic PIB. In situ quenching is the process of adding functional molecules to the polymerization reactor after all monomer is consumed. These quencher species bond to the chain ends, installing their latent functionality onto the polymer chain. To date, all quenchers utilized have been soft π-nucleophiles.

In the first project, free thiols, both aromatic and aliphatic, are shown to …

Synthesis And Characterization Of Polyisobutylene-Block-Polyamides As Novel Thermoplastic Elastomers, Lauren Renee Kucera

Dissertations

Academic research has focused on two main areas of the living carbocationic polymerization (LCP) of isobutylene (IB): (1) the in-depth study and understanding of mechanistic features of the polymerization, and (2) the utilization and manipulation of the unique aspects of PIB in order to produce practically useful polymeric materials. The research included in this dissertation focuses mainly on the latter objective. This work details three main areas of research: (1) the copolymerization of PIB and polyamides (PA) to form novel thermoplastic elastsomers (TPEs), (2) the mechanical, physical and thermal properties of the novel PIB-PA materials, and (3) the use of …

Relation Between The Adsorption Behavior And Bulk Complexation In Oppositely Charged Polyelectrolyte-Surfactant Systems: Effect Of Polyelectrolyte Concentration, Molecular Weight, Charge Localization And Backbone Rigidity/Hydrophobicity, Vipul Suhas Padman

Dissertations

Due to a wide range of applications, much emphasis has been placed on understanding the physicochemical behavior of polyelectrolyte/surfactant complexes, both at air-water interface and in the bulk. However, the correlation between the adsorption behavior and complexation in the bulk is less explored. In this research, this correlation is investigated and its dependence on polyelectrolyte concentration, molecular weight, charge localization and backbone rigidity and hydrophobicity is studied. The polyelectrolyte concentration is normalized with respect to it critical overlap concentration in order to compare the polymer in same concentration regime. Different polyelectrolyte systems were used to analyze the polyelectrolyte structural effect: …

Improving The Stability Of High And Low Bandgap Polymers Organic Photovoltaic Devices Using A Solution Based Titanium Sub-Oxide Interfacial Layer, Kurniawan Foe

Electrical & Computer Engineering Theses & Dissertations

The improvement in device efficiency has brought organic photovoltaic (OPV) devices closer to commercial viability, highlighting the importance of studying the lifetime and stability of OPV devices. At present, the lifetime and stability of OPV devices is much shorter and poor mainly caused by oxygen, moisture, and light resulting in the oxidation on low work function electrodes and the degradation of the morphology of the photoactive layer. To improve the lifetime and stability of the OPV devices, we used newly developed low bandgap polymer, PCDTBT, as the electron acceptor material and a solution based titanium sub-oxide (TiOx) interfacial layer inserted …

Degradation Kinetics And Functional Design Of Linear Self-Immolative Polymers, Ryan A. Mcbride

Electronic Thesis and Dissertation Repository

Linear self-immolative polymers display a potential to address many of the limitations in the control over the degradation process in traditional biodegradable polymers. These materials are unique relative to most degradable 
polymers, in that they undergo end-to-end depolymerization in
 response to the cleavage of a stabilizing end-capping agent. Although one of their cited 
attributes is a dependence of their degradation time on chain length, no conclusive study has been conducted to demonstrate and study this 
effect. Using a previously reported linear self-immolative backbone derived from alternating 4-hydroxybenzyl alcohol and N,N’-dimethylethylenediamine spacers, this work offers the first conclusive study demonstrating …

Butyl Rubber-Aliphatic Polyester Graft Copolymers For Biomedical Applications: Synthesis And Analysis Of Chemical, Physical And Biological Properties, Bethany A. Turowec

Electronic Thesis and Dissertation Repository

Biomaterials can be used in a wide variety of medical applications owing to their breadth of characteristics that can be imparted by varying their chemical structures. Butyl rubber (IIR), which is a copolymer of isobutylene (IB) and small percentages of isoprene (IP), is particularly attractive as a biomaterial because of its elastomeric mechanical properties, biocompatibility, impermeability and high damping characteristics. IIR is typically vulcanized through chemical-based crosslinking mechanisms. However, these methods are not acceptable for biological applications. This thesis focuses on the synthesis of IIR-polyester graft copolymers by grafting biodegradable and biocompatible polyesters including poly(caprolactone) (PCL) and poly(d,l-lactide) (PDLLA) to …

Latent Cysteine Residues From Polymers Prepared Via Free And Controlled Radical Polymerizations, Douglas Vincent Amato

Master's Theses

One less commonly used “click” reaction is thiazolidine chemistry. Thiazolidine chemistry is a commonly used reaction used in biological systems because the reaction requires the presence of both cysteine (a common amino acid) and an aldehyde or ketone. If cysteine residues could be incorporated into a polymer then a variety of applications could be developed. Polymers containing free thiols (aka thiomers) have developed in the last decade to become great mucoadhesives. If there was a facile route to control the amount of free thiols along the polymer then more fine-tuned and potentially stronger adhesives could be made. For these reasons …

Label-Free Detection Of Low Protein Concentration In Solution Using A Novel Colorimetric Assay, Molla R. Islam, Michael J. Serpe

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Dual pH and temperature sensitive microgel-based etalons were fabricated by sandwiching a “monolithic” microgel layer between two semitransparent, Au layers. The devices exhibit visual color and multipeak reflectance spectra, both of which primarily depend on the distance between the Au surfaces mediated by the microgel diameter. We found that a polycationic polyelectrolyte can penetrate through the Au overlayer to interact with negatively charged microgel confined between Au overlayers. In this submission we report that biotinylated polycationic polymer can penetrate through the Au overlayer of a poly (N-isopropylacrylamide)-co-acrylic acid (pNIPAm-co-AAc) microgel-based etalon and cause the microgel layer to collapse. The collapse …

Tuning Sol-Gel Phase Diagrams Of Doubly Thermosensitive Hydrophilic Diblock Copolymers In Water, Naixiong Jin

Doctoral Dissertations

This dissertation presents the synthesis of stimuli-responsive hydrophilic diblock copolymers and the study of their behavior in water under various conditions. The polymers were made by “living”/controlled radical polymerization. Chapter 1 presents a background of this dissertation. Chapters 2-4 describe a family of doubly thermosensitive diblock copolymers with a small amount of carboxylic acid groups incorporated into either one or both blocks. The lower critical solution temperature (LCST) of the weak acid-containing block increases with increasing pH due to the ionization of carboxylic acid. Chapter 5 presents the preparation of pH-sensitive diblock copolymer micelle-embedded agarose hydrogels.

Chapter 2 describes the …

Synthesis And Characterization Of Stimuli Responsive Polymer Brushes, Chaitra Vasant Deodhar

Doctoral Dissertations

Polyelectrolytes (PE) are the least understood polymeric systems due to their complex behavior that arises because of the intimate connection between charge and conformation. To address this challenge, my research focuses on understanding the responsive behavior of weak polyelectrolyte brushes to different stimuli such as pH, type of ion and ionic strength. In this work, weak polyelectrolyte brushes made of poly(methacrylic acid) (PMAA) and random copolymer brushes incorporating hydroxyethyl methacrylate (HEMA) as co-monomer were studied. The polymer brushes were synthesized by both “grafting to” and “grafting from” approaches and were characterized mainly by ellipsometry and neutron reflectometry.

Several methods for …

Experimenting With Polymer Blend Solar Cells And Active Layer Thickness, Ryan Blumenthal

Physics

Bulk heterojunction organic photovoltaics utilize the electrical characteristics of semi-conductive polymers. These solution processable materials are beneficial because of their low material cost, light weight, and simple fabrication requirements. Our devices employ multiple photoactive polymers, P3HT and PCPDTBT, to absorb photons over a wide spectral range. We optimized various device characteristics including thickness and thermal anneal usage to reach a power conversion efficiency of 3.0% in AM1.5 sunlight. Device performance degrades over time due to atmospheric water and oxygen, prompting us to investigate device packaging to extend cell lifetime for additional testing.

Direct Chain-End Functionalization Of Living Polyisobutylene With Phenoxyalkyl(Meth)Acrylates, Conor Patrick Roche

Master's Theses

This volume describes efforts toward the synthesis and employment of phenoxyalkyl (meth)acrylates, which were used to end-quench 1sobutylene polymers m1tiated from 2-chloro-2,4,4-tnmethylpentane (TMPCl), and 5-tert-butyl-1 ,3-d1(1-chlorol- methylethyl)benzene (bDCC), respectively, at -70 °C in 40/60 (v/v) hexane/methyl chlonde. The quencher/cham end molar rat10s typically ranged from 2.5-4, while the ratio of Lewis ac1d/cham end was vaned from approximately 3 5-6 In all cases, alkylation occurred exclusively at the para position of the quencher and no cham degradat10n was observed, even at high concentrations of TiC14 and long reaction times. Prellmmary qualitative studies mvolved the reaction of quenchers of varymg alkyl tether …

Fused Arenes-Based Molecular And Polymeric Materials For Organic Field Effect Transistors, Harista Irugulapati

Masters Theses & Specialist Projects

In the past decade, tremendous progress has been made in organic field effect
transistors. Fused oligothiophenes and anthracene molecules are fascinating
macromolecules having unique optoelectronic properties. These compounds are successfully employed as active components in optoelectronic devices including field effect transistors. Our goal is to design and synthesize conjugated molecular materials, which are highly functionalized through structural modifications in order to enhance their electronic, photonic, and morphological properties. The main desire is to synthesize novel organic fused-arenes having efficient charge carrier mobilities, as well as to optimize optical properties for organic field effect transistors (OFETs). Novel series of fused arene …

Polymers For Dna Binding, Sue Yuan Li

Seton Hall University Dissertations and Theses (ETDs)

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Relationships Between Cure Kinetics, Network Architecture, And Fluid Sensitivity In Glassy Epoxies, Katherine Lea Frank

Dissertations

Relationships between chemical structure, cure kinetics, network morphology and free volume have been correlated with fluid ingress for glassy epoxy network blends. Polymers synthesized from diglycidyl ether of bisphenol-A (DGEBA) and diglycidyl ether of bisphenol-F (DGEBF) were blended with varying amounts of triglycidyl-m-aminophenol (TGAP), tetraglycidyl-4,4-diaminodiphenylmethane (TGMP), napthylamine (NA), adamantylamine (AA), and aminopropylisobutyl polyhedral oliogmericsilsesquioxane (AI-POSS) and cured with 3,3’- and 4,4’- diaminodiphenylsulfone (DDS) to control fractional free volume, average hole size and morphology.

Varying curing profiles introduced morphological changes resulting in differences in network architectures. Epoxy with 10% NA had a smaller V_h (71 ų) …