Polymer Science Commons^™

Synthesis And Characterization Of Chemically Functionalized Shape Memory Nanofoams For Unattended Sensing Applications, Anna Paola Soliani

All Dissertations

The work in this dissertation is devoted to the synthesis and characterization of novel materials for off-line unattended sensing: shape-memory grafted nanofoams. The fabrication process and characterization of highly efficient, polymeric nanosensor element with the ability to selectively detect analytes and retain memory of specific exposure events is reported. These shape memory nanofoams could potentially act as efficient and highly sensitive coatings for evanescent waveguide-based optical monitoring systems. On exposure to specific analytes, the polymeric coatings locally change their internal structure irreversibly at the nanolevel, affecting the local optical properties such as refractive index. Currently, enrichment polymer layers (EPLs) are …

The Development Of A Laminated Copolyester Electric Guitar, Addison S. Karnes

Electronic Theses and Dissertations

This thesis is an investigation of the fabrication and assembly methodologies employed in the development of a proof-of-principle prototype electric guitar composed of laminated copolyester. The objective of the project was to develop the processes and procedures to create an optimized physical and visual bond between layers to minimize vibratory dissipation, thus maximizing sustain. A high speed CNC router, abrasive waterjet, laser engraver-cutter, as well as various manual fabrication and assembly methods were investigated in the construction of the guitar prototypes. The lamination processes explored include low-temperature, heat-assisted pressure bonding, solvent and chemical welding, and contact adhesives. The project concluded …

Low Molecular Weight Glucosamine/L-Lactide Copolymers As Potential Carriers For The Development Of A Sustained Rifampicin Release System: Mycobacterium Smegmatis As A Tuberculosis Model, Jorge Ragusa

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Tuberculosis, a highly contagious disease, ranks as the second leading cause of death from an infectious disease, and remains a major global health problem. In 2013, 9 million new cases were diagnosed and 1.5 million people died worldwide from tuberculosis. This dissertation aims at developing a new, ultrafine particle-based efficient antibiotic delivery system for the treatment of tuberculosis. The carrier material to make the rifampicin (RIF)-loaded particles is a low molecular weight star-shaped polymer produced from glucosamine (molecular core building unit) and L-lactide (GluN-LLA). Stable particles with a very high 50% drug loading capacity were made via electrohydrodynamic atomization. Prolonged …

Humic Substances-Based Polymer System, Gerard R. Thiel

Patents (University of Northern Iowa)

A system for use in forming polymer compositions, including as a replacement for phenolic based resin systems, for instance, in preparing foundry molds. In a preferred embodiment, the system includes the use of a) a polyermizable hydroxyl-containing component comprising a humic substance (as can be provided by lignite), b) an isocyanate component, and c) a catalyst, and preferably amine catalyst, component adapted to catalyze the polymerization of a) and b). The system is optionally used as binder system in the presence of a filler, such as, in combination with a foundry aggregate such as sand. A polymer system of this …

Polymer-Based Thermoelectric Devices, Stuart W. Hilsmier, Edward P. Tomlinson, Bryan Boudouris

The Summer Undergraduate Research Fellowship (SURF) Symposium

Currently, over 50% of all energy generated in the US is lost as waste heat, and thermoelectric generators offer a promising means to recoup some of this energy, if their efficiency is improved. While organic thermoelectric materials lack the efficiency of their inorganic counterparts, they are composed of highly abundant resources and have low temperature processing conditions. Recently, a new class of redox-active polymers, radical polymers, has exhibited high electrical conductivity in an entirely amorphous medium. In addition, these radical polymers have a simple synthetic scheme and can be highly tunable to provide desired electrical properties. In this study, the …

High-Productivity Membrane Adsorbers: Polymer Surface-Modification Studies For Ion-Exchange And Affinity Bioseparations, Heather Chenette

All Dissertations

This Dissertation centers on the surface-modification of macroporous membranes to make them selective adsorbers for different proteins, and the analysis of the performance of these membranes relative to existing technology. Traditional chromatographic separations for the isolation and purification of proteins implement a column packed with resin beads or gel media that contain specific binding ligands on their exposed surface area. The productivity of this process is balanced by the effective use of the binding sites within the column and the speed at which the separation can take place, in addition to the need to maintain sufficient protein purity and bioactivity. …

A Soft Condensed Matter Approach Towards Mathematical Modelling Of Mass Transport And Swelling In Food Grains, Michael Chapwanya, N. Misra

Articles

Soft condensed matter (SCM) physics has recently gained importance for a large class of engineering materials. The treatment of food materials from a soft matter perspective, however, is only at the surface and is gaining importance for understanding the complex phenomena and structure of foods. In this work, we present a theoretical treatment of navy beans from a SCM perspective to describe the hydration kinetics. We solve the transport equations within a porous matrix and employ the Flory–Huggin’s equation for polymer–solvent mixture to balance the osmotic pressure. The swelling of the legume seed is modelled as a moving boundary with …

Interfacial Interactions Between Carbon Nanoparticles And Conjugated Polymers, Yanqi Luo

Master's Theses

Conjugated polymer based electronics, a type of flexible electronic devices, can be produced from solution by traditional printing and coating processes in a roll-to-roll format such as papers and graphic films. This shows great promise for the emerging energy generation and conversion. The device performance of polymer electronics is largely dependent of crystalline structures and morphology of photoactive layers. However, the solution crystallization kinetics of conjugated polymers in the presence of electron acceptor nanoparticles has not been fully understood yet. In this study, solution crystallization kinetics of poly (3-hexylthiophene) in the presence of carbon nanotubes and graphene oxide has been …

Opto-Electronic Devices With Nanoparticles And Their Assemblies, Chieu Van Nguyen

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Nanotechnology is a fast growing field; engineering matters at the nano-meter scale. A key nanomaterial is nanoparticles (NPs). These sub-wavelength (< 100nm) particles provide tremendous possibilities due to their unique electrical, optical, and mechanical properties. Plethora of NPs with various chemical composition, size and shape has been synthesized. Clever designs of sub-wavelength structures enable observation of unusual properties of materials, and have led to new areas of research such as metamaterials. This dissertation describes two self-assemblies of gold nanoparticles, leading to an ultra-soft thin film and multi-functional single electron device at room temperature. First, the layer-by-layer self-assembly of 10nm Au nanoparticles and polyelectrolytes is shown to behave like a cellular-foam with modulus below 100 kPa. As a result, the composite thin film (~ 100nm) is 5 orders of magnitude softer than an equally thin typical polymer film. The thin film can be compressed reversibly to 60% strain. The extraordinarily low modulus and high compressibility are advantageous in pressure sensing applications. The unique mechanical properties of the composite film lead to development of an ultra-sensitive tactile imaging device capable of screening for breast cancer. On par with human finger sensitivity, the tactile device can detect a 5mm imbedded object up to 20mm below the surface with low background noise. The second device is based on a one-dimensional (1-D) self-directed self-assembly of Au NPs mediated by dielectric materials. Depending on the coverage density of the Au NPs assembly deposited on the device, electronic emission was observed at ultra-low bias of 40V, leading to low-power plasma generation in air at atmospheric pressure. Light emitted from the plasma is apparent to the naked eyes. Similarly, 1-D self-assembly of Au NPs mediated by iron oxide was fabricated and exhibits ferro-magnetic behavior. The multi-functional 1-D self-assembly of Au NPs has great potential in modern electronics such as solid state lighting, plasma-based nanoelectronics, and memory devices.

Adviser: Ravi F. Saraf

Study Of The Structure-Property Relationships That Determine The Effects Of Latexes And Starch Containing Latex Emulsions On The Performance Of The Barrier Coatings (Sub-Coat) For Paper, Joanna Marie Monfils

Master's Theses

The history of carbonless paper dates back to the 1940s. Before this, a carbon copy sheet was needed between sheets of paper to be able to produce one or more copies simultaneously during writing. The pressure from a pen or typewriter would help deposit the ink of the carbon paper onto the blank sheet of paper under the original written sheet to create a “carbon copy.” This method did however, have its disadvantages. Not only did it produce a limited number of copies, but it was also a messy process. So came the creative process of using microencapsulated dyes to …

Optimizing Polymer Fluorescence For Explosives Detection, Rose K. Cersonsky

Honors Scholar Theses

Pyrene is commonly used for explosives detection, as when mixed with polystyrene, the fluorescence intensity of the resulting film can be used as an indicator of the presence of nitro-aromatic, nitro-ether, or nitro-amine explosives. Previous studieshave tested a three-component system including pyrene, polystyrene, and a salt, tetrabutylammonium hexafluorophosphate (TBAHP). From these previous studies, it has been seen that vapor pressure of the preparation area is a governing factor in the formation of excimers, which are instrumental in achieving and maintaining fluorescence intensity. In this study, three parameters – solution concentration, film thickness, and molecular weight of polystyrene are examined to …

Aging Of A Polymer Core Composite Conductor Under Combined Ozone And Temperature Conditions, James M. Middleton

Electronic Theses and Dissertations

The next generation High Temperature Low Sag Polymer Core Composite Conductors (HTLS PCCC) can experience harsh in-service environments including high temperature and highly concentrated ozone. In some extreme cases, it is possible that the conductors will experience temperatures of up to 180°C and ozone concentrations as high as 1% (10,000 ppm). Therefore, the primary goal of this research was to determine the most damaging aging conditions which could negatively affect the in-service life of the conductors. This included characterizing the aging in ozone and at high temperature of the HTLS PCCC hybrid composite rods and neat resin. It was found …

Development Of Cementitious Materials For Adhesion Type Applications Comprising Calcium Sulfoaluminate (Csa) Cement And Latex Polymer, Joshua V. Brien

Theses and Dissertations--Civil Engineering

The objective of this research was to develop high performing polymer modified calcium sulfoaluminate (CSA) cement materials for use in applications requiring superior adhesion characteristics. Little information is available describing interactions of CSA cement containing minor phase tri-calcium aluminate (C₃A) with commonly used admixtures. Given the scarcity of information, a basic approach for developing cementitious materials was followed. The basic approach consisted of four tasks: cement design, admixture design, polymer design and testing developed materials. The iterative, time consuming process is necessary for understanding the influence of specific constituent components on overall system behavior. Results from the cement …

Electrospinning Applications Air Filtration And Superhydrophobic Materials, Negar Ghochaghi, Adetoun Taiwo

Graduate Research Posters

Electrospinning is a widely applicable technique that generates non-woven fibers in the micro and nano range. In this project two of its applications are highlighted namely filtration media and enhancement of wettability. The first project demonstrates that electrospinning can be used to produce new fiber filtration media with controlled microstructure. The bimodal and unimodal orthogonal and random filters were made and characterized against their filtration efficiency and pressure drop. Figure of Merit (FOM) was also calculated and discussed. It is shown that the FOM increases when the electrospun fibers are arranged into alternating layers of aligned course and fine fibers. …

Improving The Efficiency Of P3ht:Icba Organic Solar Cells By Modifying The Photoactive Solution Preparation Step, Matthew Blaine Samson

Electrical & Computer Engineering Theses & Dissertations

Organic solar cells (OSCs) are a promising alternative to conventional silicon solar cells. These organic devices offer the promise of facile low cost large scale solution based processing on lightweight, flexible, plastic substrates. At the present state of the technology, however, OSCs exhibit relatively low power conversion efficiencies. To improve these efficiencies, new materials are constantly being developed.

One such material is the fullerene indene-C₆₀ bisadduct (ICBA). When implemented in a poly(3-hexylthiophene-2, 5-diyl) (P3HT) : ICBA bulk heterojunction solar cell, these devices exhibit open circuit voltages exceeding 0.8 V, a value much higher than the devices made implementing phenyl-C …

Materials Education And Research In Art And Design: A New Role For Libraries (Survey Stats), Mark Pompelia

Materials Education and Research in Art and Design: A New Role for Libraries

No abstract provided.

Materials Education And Research In Art And Design: A New Role For Libraries (Program Sheet), Mark Pompelia

Materials Education and Research in Art and Design: A New Role for Libraries

No abstract provided.

Materials Education And Research In Art And Design: A New Role For Libraries (Program Booklet), Mark Pompelia

Materials Education and Research in Art and Design: A New Role for Libraries

No abstract provided.

Materials Education And Research In Art And Design: A New Role For Libraries (Website), Mark Pompelia

Materials Education and Research in Art and Design: A New Role for Libraries

No abstract provided.

Materials Collection Creation And Administration: A New Role For Libraries (White Paper), Mark Pompelia

Materials Education and Research in Art and Design: A New Role for Libraries

The Problem/Opportunity: To define, identify, and guide design-based materials collections in academic settings and foster community among those with existing collections and/or those considering creating and supporting one.

Contents and topics:

1. What is a materials collection?
2. Why have a materials collection?
3. Acquisition strategies
4. Organizational approaches
5. Programming possibilities
6. Symposium summary
7. Resources

Applied Analysis Of Ionic Polymer Metal-Composite Actuators, Siul Ruiz, Benjamin Mead, Woosoon Yim

College of Engineering: Graduate Celebration Programs

• IPMC is a type of smart material called an electroactive polymer
• Consists of an ionic polymer such as Nafion or Flemion and a conducive metal such as platinum or gold
• COMSOL multi-physics simulations accurately model the experimental displacement results
• Optimization performed using the multi-physics model to find the maximum deflection, force, and twisting
• Using the closed loop control system accurate IPMC tip location can be achieved
• This control system has been extended to function using a computer mouse as an input

Measuring Acoustic Attenuation Of Polymer Materials Using Drop Ball Test, Yi Zhang

Doctoral Dissertations and Master's Theses

Polymers are often used for vibration damping and energy absorption. The effect of a material in reducing the strength of sound waves traveling through it is called acoustic attenuation. In the past, attenuation has mostly been evaluated in the MHz frequency range, using a pulse generator and transmitting transducer as the wave source. However, most real acoustic activities occur at frequencies up to a few hundred kHz. Here, a simple drop ball mechanism is used to generate acoustic source waves in the kHz range, and the attenuation capacities of several solid materials are measured. The recorded waveforms substantially differ between …

Characterization Of And Controlling Morphology Of Ultra-Thin Nanocomposites, Guy C. Laine

Theses and Dissertations--Chemical and Materials Engineering

Ultrathin film nanocomposites are becoming increasingly important for specialized performance of commercial coatings. Critical challenges for ultrathin film nanocomposites include their synthesis and characterization as well as their performance properties, including surface roughness, optical properties (haze, refractive index as examples), and mechanical properties. The objective of this work is to control the surface roughness of ultrathin film nanocomposites by changing the average particle size and the particle volume fraction (loading) of monomodal particle size distributions. This work evaluated one-layer and two-layer films for their surface properties. Monodispersed colloidal silica nanoparticles were incorporated into an acrylate-based monomer system as the model …

Flexural Rigidity Characterization Of Retrofitted Frp Plates, Steven J. Makonis Jr., Stella B. Bondi, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

Presented herein is a procedure and numerical results for flexural rigidity characterization of Fiber Reinforced Polymer (FRP) plates retrofitted with various types of fabrics. The FRP plates were retrofitted with Kevlar® 49 (Aramid), Carbon Fiber (Harness-Satin H5), and Unidirectional Carbon Fiber (T700 Aerospace Grade) fabrics, respectively. The FRP plate flexural rigidity values were calculated with a central finitedifference iterative scheme while utilizing the experimental load-deflection relations based on bending tests. The tests were performed on each plate by applying a concentrated load at the center. A fourth-order partial differential equation of plate equilibrium was adopted to estimate the plate flexural …

Determining A Method For Rendering Low Cost Cdse(Zns) Core(Shell) Quantum Dots Aqueous Soluble Via Amphiphilic Polymer Wrapping, Patrick Mcbride

Materials Engineering

Herein is described the procedure of two amphiphilic polymer wrapping techniques that may be employed for obtaining aqueous soluble quantum dots (QDs) for use in biological fluorescent imaging applications. The advent of QDs has led to new nanoscale fluorescent materials that exhibit unparalleled quantum yields (QYs), high resistance to photobleaching, tunable emissions, and
absorption over a large optical range. However, the QD synthesis employed here at Cal Poly to obtain bright, photostable CdSe(ZnS) core(shell) QDs involves the use of organic solvents and surfactants, leading to hydrophobic QDs. Since all of biology relies on aqueous solubility, this hydrophobicity creates a major …

Preparation Of Styrene Acrylic Copolymer Toner Resin By Solution Polymerization., Neo Su Siang

Student Works (2010-2019)

This project has investigated solution polymerization to produce toner resins. There are three stages: (i) synthesis of low molecular weight styrene acrylic copolymer; (ii) synthesis of high molecular weight styrene acrylic copolymer; (iii) mixing high and low molecular weight copolymers. Gel Permeation Chromatography (GPC) was used to study molecular weight distributions, Melt Flow Index (MFI) Instrument to study the flowability of resin, Differential Scanning Calorimetry (DSC) to study the thermal properties of resin, and acid number to quantitate the amount of acidic group in the resin. A comparison of properties between the experimental samples, patent’s claims, and commercial resins had …

Characteristics Of Proton Conducting Pva-Chitosan Polymer Blend Electrolytes., Mohd Fakhrul Zamani Abdul Kadir

Student Works (2010-2019)

The main focus of this present work is to build a good conducting solid polymer electrolyte (SPE) based on chitosan and poly(vinyl alcohol)(PVA) blend. Solution cast technique has been employed to produce sample films in this work. From the scanning electron micrographs (SEM) the surface morphology of the blend containing 40 wt.% chitosan and 60 wt.% PVA (C4P6) is homogenous and miscible in one and another. The C4P6 film is the most amorphous and is the best candidate for the polymer host in the electrolyte systems studied in the present work. Ammonium Nitrate (NH4NO3) is the doping salt that provides …

Thermo-Electrical And Mechanical Studies On Polymer-Organically Modified Montmorillonite Composite., Norhana Abdul Halim

Student Works (2010-2019)

The field of polymer-nanoclay composite has attracted a lot of attention in materials studies due to the dramatic improvement on polymers characteristics. For example mechanical and thermal properties, chemical resistance as well as the reduced gas permeability. However, structural changes and the mechanisms that may contribute to these improvements are not fully understood. In this work, the study on polymer nanoclay composite concentrates on the effects of OMON inclusion within different polymer matrix systems. The matrixes are a series of natural rubbers (Standard Malaysia Rubber – Latex grade (SMRL); Deproteinized Natural Rubber (DPNR) and Epoxidized Natural Rubber (ENR-50)), plasticized Polyvinyl …

Electrical And Structural Studies Of Polyacrylonitrile (Pan) Complexed With Inorganic Salts., Khairul Bahiyah Md Isa

Student Works (2010-2019)

In the present study, polymer electrolyte films composed of polyacrylonitrile (PAN) as a host polymer, ethylene carbonate (EC) as the plasticizer and lithium triflate (LiCF3SO3) and sodium triflate (NaCF3SO3) as dopant salts were prepared by the solution cast technique. Five systems of polymer electrolytes films have been prepared; these systems are the plasticized-PAN system i.e. PAN-EC system, two salted-PAN systems i.e. PAN-LiCF3SO3 and PAN-NaCF3SO3, and two plasticized-salted PAN systems i.e. PAN-EC-LiCF3SO3 and PAN-EC-NaCF3SO3. The pure PAN film was prepared as a reference. The ionic conductivity for each system is characterized using impedance spectroscopy. The room temperature conductivity of the pure …

Thermal Damage Approach Of Concrete: Application To Specimens Subjected To Combined Compressive And High Temperature Loads, Abdellah Menou, Ghassan Mounajed, Hocine Boussa, Christian La Borderie, Khalid Lafdi

Chemical and Materials Engineering Faculty Publications

Within the framework of study of concrete structures subjected to fire, .a theoretical and experimental work was conducted. The aim of this study was to investigate and to model the damage mechanisms of concrete after their exposure to high temperatures. The multiphase Digital Concrete Model as well as the damage model, MOD EV, which were both implemented on the finiteelem~ rit software package, SYMPHONIE, were used simμltaneously to assess the thermal damage of the concrete. In order to validate the thermal damage model, an experimental investigation was performed. The mechanical characteristics of 5 cementitious materials, which included cement paste, mortar, …