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Protein Charge Anisotropy Mediated Self-Association And Phase Separation, Daniel P. Seeman

Doctoral Dissertations

Protein charge anisotropy results from the asymmetric distribution of charged residues on the exterior of a particular protein. Interactions between proteins and other macromolecules can be described in terms of attractive electrostatics; since electrostatic free energies, at optimal I, are on the order of kT, it is unlikely that such associations would result in desolvation, thus it is reasonable to consider such intermolecular attractions as being mediated by hydrated protein surfaces. Such interactions can be broken down in terms of a single protein interacting with a range of “binding partners”, including (1) protein-protein interactions, (2) protein-polymer interactions, and …

Aspects Of Physical Aging And Solid State Processing Of Polymeric Glasses, Angel Cugini

Doctoral Dissertations

This thesis focuses on unconventional methods to improve the mechanical properties of glassy polymers such as PMMA, Tritan™ Copolyester, and epoxy-based thermosets by influencing the intrinsic mechanical behavior through solid-state processing. The solid-state processing includes pre-stress, mechanical rejuvenation, and mechanical work hardening that cause changes in microscopic conformation structure and dynamics of glassy polymers and enhance properties such as non-linear deformation behavior and low and high velocity fracture. To utilize such unconventional techniques, one needs to understand fundamental origins of dynamics in polymeric glasses where the chain segments are not completely frozen and the segmental diffusion displays high degree of …

Ultra-Thin Polymer Films And Hierarchical Composites: Processing And Mechanical Properties, Yujie Liu

Doctoral Dissertations

Properties and fabrications of ultra-thin polymer films and hierarchical composites are of great interest in packaging, electronics, separations, and other manufacturing fields. However, due to the inherently fragile nature of ultra-thin polymer films, measuring their properties has proven difficult. Additionally, variables controlling thin polymer patterns (e.g. substrate wetting property) and composites (weight percent of particulates in matrix) formation have not been fundamentally well understood. Within this spectrum, fundamental understanding of formation mechanisms of these patterns and composites are needed. Additionally, a new characterization technique is required to be able to measure the mechanical properties of fabricated composites and thin films. …

Synthesis, Optimization, And Degradation Of A Fish Glue/Plga Polymer., Adam T. Schworer 1989-

Electronic Theses and Dissertations

Biomaterials used for tissue engineering, specifically polymers, come from either naturally occurring, like gelatin or collagen, or synthetic sources, such as polyesters. Often times, it is advantageous to combine biomaterials in order to maximize certain material properties, such as cellular adhesion and degradation. The purpose of this study is to provide direction for the synthesis, characterization, and a combination of a combination biomaterial between fish glue (FG), a natural source polymer, and poly-lactic-co-glycolic acid (PLGA), a synthetically made polyester. First, FG is characterized for molecular weight via Gel Permeation Chromatography, GPC. Two combination methods to mix FG/PLGA solutions are then …

Effect Of Surfactant Architecture On Conformational Transitions Of Conjugated Polyelectrolytes, Greg A. Braggin

Master's Theses

Water soluble conjugated polyelectrolytes (CPEs), which fall under the category of conductive polymers, possess numerous advantages over other conductive materials for the fabrication of electronic devices. Namely, the processing of water soluble conjugated polyelectrolytes into thin film electronic devices is much less costly as compared to the processing of inorganic materials. Moreover, the handling of conjugated polyelectrolytes can be performed in a much more environmentally friendly manner than in the processing of other conjugated polymers because conjugated polyelectrolytes are water soluble, whereas other polymers will only dissolve in toxic organic solvents. The processing of electronic devices containing inorganic constituents such …

The Kinetics Of Drug Dissolution In Polymers During Hot-Melt Extrusion, Huayang Fang

Theses

Extrusion has been a most important and widely used continuous process in polymer processing for over one hundred and fifty years. However, it has only been recently applied and adopted by the pharmaceutical industry to prepare solid oral dosage formulations with increased bioavailability for the poorly-water soluble drugs and controlled release characteristics for the water-soluble drugs. In pharmaceutical Hot-melt extrusion poorly water soluble drug particulates are mixed with water soluble polymer excipient particulates and fed in the extruder, where the polymer is melted, after which the drug particulates begin to dissolve into the polymer melt. Extrusion-generated mixing accelerates dissolution process. …

Development Of Nanofiber Scaffolds With Controllable Structure And Mineral Content For Tendon-To-Bone Repair, Justin Herrold Lipner

McKelvey School of Engineering Theses & Dissertations

Rotator cuff tears are common and lead to significant pain and disability. Effective repair of torn rotator cuff tendons requires healing of tendon to bone. Unfortunately, healing does not reproduce the structural and compositional features of the natural tendon-to-bone bone attachment that are necessary for effective load transfer, and surgical repairs often rupture.

Recent efforts for improving tendon-to-bone healing have focused on tissue engineering approaches. Scaffolds, cells, and/or growth factors are implanted at the repair site to guide the healing process and improve outcomes. To that end, a polymer-mineral tissue engineered scaffold was developed for this thesis which mimics two …

Design, Synthesis, And Bio Relevant Applications Of Zwitterionic Amphiphilic Macromolecular Assemblies, Rajasekhar Reddy Rami Reddy

Doctoral Dissertations

Supramolecular nanoassemblies capable of reducing non-specific interactions with biological macromolecules, such as proteins, are of great importance for various biological applications especially for targeted drug delivery therapeutics. Recently, zwitterionic materials have been shown to reduce non-specific interactions with biomolecules, owing both to their charge neutrality and their ability to form strong hydration layer around zwitterions via electrostatic interactions. This dissertation focuses on design, synthesis, thorough characterization, and applications of zwitterionic amphiphilic dendrimers and polymeric materials. Firstly, A new triazole-based zwitterionic moiety was conceived and incorporated as the hydrophilic functionality in facially amphiphilic dendrons. Self-assembly characteristics and the structural and functional …

Tailoring Nanoparticles And Polymers For Cooperative Interfacial And Surface Interactions, Irem Bolukbasi

Doctoral Dissertations

This thesis describes the synthesis of chemically functionalized nanoparticles and their behavior at interfaces and in conjunction with polymers. Solid-liquid, liquid-liquid, and air-liquid interfaces are useful platforms for studying nanoparticle assembly, especially when nanoparticles are functionalized to enable their segregation to the interface. At the liquid-liquid interface, double emulsions droplets, both oil-in-water-in-oil and water-in-oil-in-water, stabilized with nanoparticles were prepared. This involved gold nanoparticles stabilizing oil-in-water droplets, and CdSe quantum dots stabilizing water-in-oil droplets. These double emulsion droplets were by simply shaking to give polydisperse droplets, or in a well-defined fashion by microcapillary flow focusing. When nanoparticle-stabilized double emulsions were sized …

Synthesis, Characterization, And Electrochemical Properties Of Polyaniline Thin Films, Soukaina Rami

USF Tampa Graduate Theses and Dissertations

Conjugated polymers have been used in various applications (battery, supercapacitor, electromagnetic shielding, chemical sensor, biosensor, nanocomposite, light-emitting-diode, electrochromic display etc.) due to their excellent conductivity, electrochemical and optical properties, and low cost. Polyaniline has attracted the researchers from all disciplines of science, engineering, and industry due to its redox properties, environmental stability, conductivity, and optical properties. Moreover, it is a polymer with fast electroactive switching and reversible properties displayed at low potential, which is an important feature in many applications. The thin oriented polyaniline films have been fabricated using self-assembly, Langmuir-Blodgett, in-situ self-assembly, layer-by-layer, and electrochemical technique. The focus of …

Solute Partitioning In Elastin-Like Polypeptides: A Foundation For Drug Delivery Applications, Eric Helm

ETD Archive

No abstract provided.

Novel Sustainable Polymers Derived From Renewable Rosin And Fatty Acids, Perry Wilbon

Theses and Dissertations

In the work of this dissertation, polymers derived from renewable bio-based resources prepared by various polymerization techniques were investigated. The properties of these polymeric materials were characterized and discussed. Rosin was first converted into acrylate or methacrylate monomers for atom transfer radical polymerization (ATRP). Second, rosin was combined with vegetable oil to produce completely renewable novel polyesters by acyclic diene metathesis (ADMET) polymerization. Third, degradable block copolymers were synthesized composed of polycaprolactone and rosin grafted polycaprolactone with the aid of ring-opening polymerization (ROP). Finally, degradable polyesters were produced using vegetable oil derivatives as starting materials. These new rosin and fatty …

Initiated Chemical Vapor Deposition (Icvd) Polymer Thin Films : Structure-Property Effects On Thermal Degradation And Adhesion, Vijay Jain Bharamaiah Jeevendrakumar

Legacy Theses & Dissertations (2009 - 2024)

Opportunities and challenges for chemical vapor deposition (CVD) of polymer thin films stems from their applications in electronics, sensors, and adhesives with demands for control over film composition, conformity and stability. Initiated chemical vapor deposition (iCVD) is a subset of the CVD technique that conjoins bulk free-radical polymerization chemistry with gas-phase processing. The novelty of iCVD technique stems from the use of an initiator that can be activated at low energies (150 – 300 °C) to react with surface adsorbed monomer to form a polymer film. This reduces risk for potential unwarranted side-reactions.

Interactions Between Phospholipids And Polymers With Time Resolved Fluorescence Spectroscopy, Zachary E. Hier

Williams Honors College, Honors Research Projects

Interactions between macromolecule species and fluorescently labeled phospholipids were explored in supported lipid bilayers (SLBs). The concentration and the lateral mobility of the labeled phospholipids within the confocal volume were determined via fluorescence correlation spectroscopy. Low molecular weight polystyrene was used for the neutral charged macromolecule. Three separate concentrations of polystyrene were used and a significant change in lateral mobility of phospholipids was found for the SLB doped with all three concentration of styrene from polystyrene (molecular weight = 1000). Polyester with mimic lysine pendant groups was used for the cationic polymer at physiological pH. A large decrease in the …

Physicochemical And Structural Analysis Of Polymers As Putative Drugs, Meghan L. Thompson

Theses and Dissertations

Sulfated low molecular weight lignins (LMWLs) have shown good activity as anticoagulants by allosterically inhibiting thrombin, as well as promising agents for treating emphysema through inhibition of elastolysis, oxidation, and inflammation. Sulfated LMWLs are chemo-enzymatically synthesized from starting monomers caffeic, ferulic, and sinapic acid into sulfated dehydropolymers known as CDS, FDS, and SDS. To further the LMWLs’ development as drugs, their structural composition and physicochemical characteristics were defined in this work. The molecular weight distribution profile of the sulfated LMWLs from size exclusion chromatography performed on a high pressure liquid chromatography system (SEC-HPLC) changed from bimodal when no surfactant is …