Polymer and Organic Materials Commons^™

Optimization Composition Of The Wood-Polymer Composition Based On Polyvinylchloride, Aliyev Sunnatulla, Ilkhamov Giyos, Jurayev Asror, Magrupov Farkhad

CHEMISTRY AND CHEMICAL ENGINEERING

The objective of the reaserch is to elaboration the composition of a wood-polymer composition based on polyvinyl chloride with improved performance properties. The influence of the components of the composition - modifiers, lubricants, regulators and stabilizers - on the properties of the composition was researched. Optimization of the composition of wood-polymer composition based on PVC made it possible to obtain a material with higher strength and fire resistance.

Theory And Improved Methods For Probing The Cavitation To Fracture Transition, Christopher Barney

Doctoral Dissertations

A material is considered soft when its bulk modulus is significantly greater than its shear modulus. Rubbery polymers are a class of soft materials where resistance to extension is mainly entropic in nature. Polymeric soft solids differ from liquids due to the presence of a percolated network of strong bonds that resist deformation and flow on a given time scale. The incompressible nature, entropically driven elasticity, and molecular scale network structure of soft polymeric solids combine to impart unique mechanical behavior that often results in complex material responses to simple loading situations. An important example of this is cavitation in …

Stress Relaxation In Orthodontic Aligner Plastics; An In Vitro Comparison Study, Kristopher J. Keller

Theses & Dissertations

The purpose of this study was to ascertain if repeated stresses from extension cycling would result in accumulated damage in aligner materials and affect force delivery. A secondary goal was to identify potential differences in mechanical behavior present among orthodontic aligner polymers. Four thermoplastic polymers (Essix ACE, Taglus, Zendura, and Zendura FLX) were thermoformed, cut into strips, and extension cycled to 0.4 millimeters in a 37C water bath. Force decay, maximum and minimum force, and elastic modulus were measured during cycling. Additional samples were subjected to controlled tension until failure, allowing the measurement of yield strength, ultimate strength, and elastic …

Two New Finite Element Schemes And Their Analysis For Modeling Of Wave Propagation In Graphene, Jichun Li

Mathematical Sciences Faculty Research

© 2020 The Author(s) In this paper, we investigate a system of governing equations for modeling wave propagation in graphene. Compared to our previous work (Yang et al., 2020), here we re-investigate the governing equations by eliminating two auxiliary unknowns from the original model. A totally new stability for the model is established for the first time. Since the finite element scheme proposed in Yang et al. (2020) is only first order in time, here we propose two new schemes with second order convergence in time for the simplified modeling equations. Discrete stabilities inheriting exactly the same form as the …

Engineered Carbon Materials With Nano-Graphitic Domains Derived From Lignin, Valerie Garcia Negron

Doctoral Dissertations

This work focuses on establishing a comprehensive understanding of lignin-derived materials as a function of carbonization with the goal of identifying processing-structure-property-performance relationships. A combination of modeling, statistical, and empirical materials characterization techniques are applied to lignin materials varying in feedstock source, extraction method, and processing conditions. The first part of this study evaluates the structure of carbon composite materials, possessing both crystalline and amorphous domains, using scattering techniques. One approach performs atomistic simulations of a proposed structure, from which the analogous scattering pattern can be obtained for validation. An alternative approach based on a hierarchical decomposition of the radial …

Discontinuous Recycled And Repurposed Carbon Fiber Reinforced Thermoplastic Organosheet Composites, Philip R. Barnett

Doctoral Dissertations

There is a significant need for low cost, high volume composites in the automotive industry to aid in vehicle lightweighting and safety. The current state-of-the-art severely compromises the mechanical properties of composites to achieve cost and cycle time goals. In this dissertation, a novel composite format, termed discontinuous carbon fiber organosheets, using recycled and repurposed carbon fibers in a thermoplastic matrix is developed and studied. Unlike traditional composites, the long fiber length and rapid processing time yield mechanical properties and cycle times competitive with automotive metals.

Several studies were performed to characterize this new material format. First, samples were manufactured …

Processing-Structure-Performance Relationships In Fused Filament Fabricated Fiber Reinforced Abs For Material Qualification, William Howard Ferrell

Doctoral Dissertations

This dissertation uses the processing-structure-performance relationships to elucidate future needs in qualification of materials manufactured by fused filament fabrication and also introduces a previously unused testing method for the determination of fracture toughness in these materials. Fused filament fabrication (FFF) is an additive manufacturing technique that utilizes the layering of deposited molten plastic in two dimensional shapes to create three dimensional objects. This technique has gained traction over the past two decades as a disruptive manufacturing technology that promises many benefits. In order for FFF to truly be a staple in manufacturing spaces across the world for the production of …

Adhesion And Deformation Mechanisms Of Polydopamine And Polytetrafluoroethylene: A Multiscale Computational Study, Matthew Brownell

Graduate Theses and Dissertations

Polydopamine (PDA) has been shown to bond via covalent bonding, van der Waals forces, and hydrogen bonding and is known to adhere strongly to almost any material. The application of PDA between a substrate and a PTFE surface coating has resulted in low friction and a greatly reduced wear rate. Previous research probing the capabilities and limitations of PDA/PTFE films have studied the wear and mechanical properties of the film, but the overall adhesive and deformation mechanisms remain unclear.

In this research, we investigate the tribological properties of PDA and PTFE molecules and composites from the atomic to the microscale …

3-D Fabry–Pérot Cavities Sculpted On Fiber Tips Using A Multiphoton Polymerization Process, Jonathan W. Smith, Jeremiah C. Williams, Joseph S. Suelzer, Nicholas G. Usechak, Hengky Chandrahalim

Faculty Publications

This paper presents 3-D Fabry–Pérot (FP) cavities fabricated directly onto cleaved ends of low-loss optical fibers by a two-photon polymerization (2PP) process. This fabrication technique is quick, simple, and inexpensive compared to planar microfabrication processes, which enables rapid prototyping and the ability to adapt to new requirements. These devices also utilize true 3-D design freedom, facilitating the realization of microscale optical elements with challenging geometries. Three different device types were fabricated and evaluated: an unreleased single-cavity device, a released dual-cavity device, and a released hemispherical mirror dual-cavity device. Each iteration improved the quality of the FP cavity's reflection spectrum. The …

Growth And Characterization Of Semiconductor Materials And Devices For Extreme Environments Applications, Abbas Sabbar

Graduate Theses and Dissertations

Numerous industries require electronics to operate reliably in harsh environments, such as extreme high temperatures (HTs), low temperature (LT), radiation rich environments, multi-extreme, etc. This dissertation is focused on two harsh environments: HT and multi-extreme.

The first study is on HT optoelectronics for future high-density power module applications. In the power modules design, galvanic isolation is required to pass through the gate control signal, reject the transient noise, and break the ground loops. The optocoupler, which consists of a lighting emitting diode (LED) and photodetector (PD), is commonly used as the solution of galvanic isolation at room temperatures. There is …

Direct Solar Absorption Nanoparticle Doped Membranes For A Hybrid Membrane Distillation And Photovoltaic Cell, Alejandro Espejo Sanchez

Boise State University Theses and Dissertations

The growing demand for clean water supplies is driving the need for an innovative approach of water desalination. Developing a method for treating water with high salinities is possible with membrane distillation (MD). Additionally, MD is very attractive for pairing with solar energy due to the low temperature requirements. The integration of a membrane distillation system with a photovoltaic (PV) system will result in the co-production of electricity and clean water, thereby improving the economics of MD. Such a hybrid system will directly absorb thermal energy in the membrane for desalination while taking advantage of the spectrally selective nature of …

Practical Adhesion Measurements In Organic Coatings; Advancing Understanding And Mechanical Methods Development, Diana Gottschalk

Dissertations

“Adhesion” can be considered either a mechanical or chemical phenomenon. The mechanical interpretation describes the difficulty of separating surfaces and is useful for quantifying performance within applications that depend on bulk and interfacial properties. Chemical adhesion describes interfacial resistance to chemical attack and does not depend on bulk properties. Predicting chemical failure through mechanical measurement is confounded by the influence of bulk properties. However, the prospect is attractive because of the robust tolerance for sample geometries, allowing experiments to resemble an end-use system. The present work's primary goal was to elevate mechanical methods to provide a detailed interfacial characterization of …

A Bibliometric Survey On Polymer Composites In Energy Storage Applications, Babaji Ghule, Meena Laad

Library Philosophy and Practice (e-journal)

Ceramic polymer composites have gained a significant place in energy storage applications for electrical capacitors due to their distinguished properties. There is a huge demand of capacitors with high energy density, high dielectric strength, negligibly low dielectric loss, light weight, chemically less reactive in energy storage applications. These requirements can be fulfilled by ceramic polymer composites only which exhibit all the above-mentioned characteristics. Considering the huge demand of such capacitors, it has attracted the attention of researchers around the world. The present work attempts to summarise all the research conducted on Polymer Composites for energy storage applications and provides an …

Ensemble Labeling Towards Scientific Information Extraction (Elsie), Erin Murphy

College of Computing and Digital Media Dissertations

Extracting scientific facts from unstructured text is difficult due to challenges specific to the ambiguity of the language, the complexity of the scientific named entities and relations to be extracted. This problem is well illustrated through the extraction of polymer names and their properties. Even in the cases where the property is a temperature, identifying the polymer name associated with the temperature may require expertise due to the use of acronyms, synonyms, complicated naming conventions and by the fact that new polymer names are being “introduced” to the vernacular as polymer science advances. While there exist domain-specific machine learning toolkits …

General-Purpose Coarse-Grained Toughened Thermoset Model For 44dds/Dgeba/Pes, Michael M. Henry, Stephen Thomas, Mone’T Alberts, Carla E. Estridge, Brittan Farmer, Olivia Mcnair, Eric Jankowski

Materials Science and Engineering Faculty Publications and Presentations

The objective of this work is to predict the morphology and material properties of crosslinking polymers used in aerospace applications. We extend the open-source dybond plugin for HOOMD-Blue to implement a new coarse-grained model of reacting epoxy thermosets and use the 44DDS/DGEBA/PES system as a case study for calibration and validation. We parameterize the coarse-grained model from atomistic solubility data, calibrate reaction dynamics against experiments, and check for size-dependent artifacts. We validate model predictions by comparing glass transition temperatures measurements at arbitrary degree of cure, gel-points, and morphology predictions against experiments. We demonstrate for the first time in molecular simulations …

Effect Of Nanofiller Coating And Loading On Facial Elastomer Physical Properties, Rahmi K. Aulia

Theses & Dissertations

Current materials used for facial prostheses are far from being desirable, and improved properties with “skin-like” feel are needed. This study evaluates property changes induced by sequential additions of uncoated and hydrophobic-coated nano-SiO₂ to polydimethylsiloxane (PDMS) and compares them with those measured for conventional submicron SiO₂-filled materials. Each filler type was sequentially added to vinyl-terminated PDMS at 0%, 0.5%, 5%, 10%, and 15% by weight. Tensile, tear, Durometer hardness, translucency and viscoelastic properties were evaluated, with hardness and translucency also evaluated following 3000 hours of outdoor weathering. Results demonstrated that 15% coated nano-SiO₂-filled PDMS materials …

Maleic Anhydride Compatibilized Peach Waste As Filler In Polypropylene And High Density Polyethylene Biocomposites, Caralyn Wong, Stephanie Jung, Joongmin Shin, Ajay Kathuria

Master's Theses

It is estimated that roughly 103, 515 tons of peach waste is produced annually in the US. The majority of the waste is disposed of in landfills, which contributes to climate change as they release 93 million metric tons of CO₂ equivalent. Peach waste principally consists of remaining stone and seed after flesh removal. The agro-waste includes both cellulose and lignin, which can be utilized as a filler in plastic packaging to reduce carbon footprints and material cost. The objectives of this research are (1) to develop peach flour (PF)-filled biocomposites with a polyolefin matrix using maleic anhydride-g-high density …

Nano- And Micro-Structured Temperature-Sensitive Hydrogels For Rapidly Responsive Devices, Qi Lu

Doctoral Dissertations

This thesis aims to extend the understanding and explore the application of temperature-responsive hydrogel systems by integrating microelectromechanical systems (MEMS). Stimuli-responsive hydrogel systems are immensely investigated and applied in numerous fields, and interfacing with micro- and nano-fabrication techniques will open up more possibilities. In Chapter 2, the first biologically relevant, in vitro cell stretching device based on hydrogel surface instability was developed. This dynamic platform is constructed by embedding micro-heater devices under temperature-responsive surface-attached hydrogels. The fast and regional temperature change actuates the stretching and relaxation of the seeded human artery smooth muscle cell (HASMC) via controllable surface creasing instability. …

Tacky Elastomers To Enable Tear-Resistant And Autonomous Self-Healing Semiconductor Composites, Song Zhang, Yu-Hsuan Cheng, Luke Galuska, Anirban Roy, Matthias Lorenz, Beibei Chen, Shaochuan Luo, Yen-Ting Li, Chih-Chien Hung, Zhiyuan Qian, Peter Blake Joseph St. Onge, Gage T. Mason, Lewis Cowen, Dongshan Zhou, Sergei I. Nazarenko, Robson F. Storey, Bob C. Schroeder, Simon Rondeau-Gagné, Yu-Cheng Chiu, Xiaodan Gu

Faculty Publications

Mechanical failure of π-conjugated polymer thin films is unavoidable under cyclic loading conditions, due to intrinsic defects and poor resistance to crack propagation. Here, the first tear-resistant and room-temperature self-healable semiconducting composite is presented, consisting of conjugated polymers and butyl rubber elastomers. This new composite displays both a record-low elastic modulus (

Investigation Of Neoprene Medical Gloves: Analysis Of Material Properties, Durability, And Bacterial Barrier Efficacy, Amanda Agui

Honors Scholar Theses

This work aims to investigate the material properties, durability, and bacterial barrier efficacy of neoprene for applications in the healthcare/medical field. A special focus on material stiffness and fatigue failure will be explored. Additionally, manufacturer regulations and testing will be inspected to ensure medical gloves made of neoprene blends have a proper lifespan for its desired application in the healthcare community. The resistance of protective gloves and its ability to withstand perforation failure will be investigated to guarantee the safety of users holds extreme importance. Lastly, an analysis of the bacterial barrier efficacy of neoprene gloves will be determined.

Nature-Inspired Electrode Materials For Next Generation Sustainable Energy Storage, Mikhail Miroshnikov

Dissertations, Theses, and Capstone Projects

Despite revolutionizing the world of portable electronics, the contemporary lithium-ion battery (LIB) suffers from challenges associated with the cost, safety, and environmental impact of transition metal oxide-based intercalation cathodes. To alleviate these issues, naturally occurring organic molecules may serve as sustainable alternatives to traditional inorganic cathode materials. The electrochemical properties of organic compounds are derived from redox-active functional groups containing oxygen, nitrogen and sulfur. Additionally, these functional groups are capable of coordinating metal ions beyond lithium, allowing for compatibility with sodium-ion batteries (SIBs) and other earth abundant metal-based energy storage systems. However, despite competitive performance against commercialized cathode materials, much …

Fly Ash Based Geopolymer For High Temperature And High Compressive Strength Applications In Aggressive Environment, Aaryan Manoj Nair, Akm S. Rahman

Publications and Research

Geopolymers are the results of geosynthetic reactions between aluminosilicates and strong bases. This results in chemical bonds between aluminum (Al), Silicon (Si)and oxygen (O) composing polymer rings in tetrahedral coordination. These bonds give them widespread useful applications such as high heat bearing ceramics, and base construction material whilst being far more environmentally conscious. The purpose of the experiment is to examine the effect of Silicon Carbide whisker and inorganic glass particles on thermal and mechanical properties of Geopolymers. This study will help understand the effect of various compositions and concentrations of SiO₂ in mechanical strength. In this experiment, the …

Effect Of Post-Consumer Content And Bioplastic Incorporation On Polymeric Resin In Consumer Applications, Shelby Bicknell

Electronic Theses & Dissertations

Controversy surrounds the use of plastic products, primarily due to their potentially negative impact on the environment at the end of their lifecycle. The most widely used plastics are manufactured from petrochemicals such as petroleum, coal or natural gas. Petrochemical plastics are not able to readily breakdown in the environment, which aggravates the existing pollution problems. Fortunately, there are eco-friendly alternatives to petrochemical-based plastics. Bioplastics may be derived from renewable sources, biodegradable, or both. Bio-based plastics are plastics that may be derived from renewable biomass sources including, but not limited to, vegetable oils, cornstarch, straw, woodchips, and food waste. They …

Effects Of Hard-To-Soft Segment Ratios On The Synthesis And Physico-Mechanical Properties Of Polyurethane Films, Aaron C. Wilson

Mechanical Engineering Theses

Blood-contacting cardiovascular stents often induce a secondary clotting event due to unrestricted enzymatic activities. The use of hemocompatible polyurethane coatings on these implantable devices is one of the most promising methods to reduce device rejection. In this study, four commercial polyurethane films of various thicknesses and compositions were evaluated for their anticoagulation properties. Results suggested that these films exhibited excellent thermal and physico-mechanical properties while capable of increasing contact time with blood plasma by over a thousand-fold as compared to a control surface. Due to the unknown structure and composition of these commercial films, polyurethane samples were synthesized from toluene …

Resistive Switching Characteristics Of Nanostructured And Solution-Processed Complex Oxide Assemblies, Zimu Zhou

Doctoral Dissertations

Miniaturization of conventional nonvolatile (NVM) memory devices is rapidly approaching the physical limitations of the constituent materials. An emerging random access memory (RAM), nanoscale resistive RAM (RRAM), has the potential to replace conventional nonvolatile memory and could foster novel type of computing due to its fast switching speed, high scalability, and low power consumption. RRAM, or memristors, represent a class of two terminal devices comprising an insulating layer, such as a metal oxide, sandwiched between two terminal electrodes that exhibits two or more distinct resistance states that depend on the history of the applied bias. While the sudden resistance reduction …

Selfsame Epoxide-Amine Microparticle Systems: Investigation Of Crosslink Density, John J. Peyrefitte

Honors Theses

Epoxide-amine matrix materials containing microparticles with the same chemical composition provide a model system to study interphase formation in highly crosslinked epoxide-amine matrix materials. The epoxide monomer was varied between three different monomer systems to study the model system’s relationship with crosslink density. The same amine monomer, cure procedure, and stoichiometric ratio of epoxide and amine groups were used to prepare each type of microparticle and matrix material. The differences in the epoxide monomer structure affected the crosslink density of the unmodified matrix material, which was concluded to influence the effect of microparticle presence on crosslink density. For the unmodified …

Hydrolytic Degradation Study Of Polyphosphazene-Plga Blends, Riley Blumenfield

Honors Scholar Theses

The synthesis and in vitro degradation analysis of thin films of poly[(glycineethylglycinato)₇₅(phenylphenoxy)₂₅phosphazene]
(PNGEG₇₅PhPh₂₅) and poly[(ethylphenylalanato)₂₅(glycine-
ethylglycinato)₇₅phosphazene] (PNEPA₂₅GEG₇₅) blended with poly(lactic-co-glycolic acid) (PLGA) was conducted to determine the blends’ potential for use as scaffolding materials for tissue regeneration applications. The samples were synthesized with glycylglycine ethyl ester (GEG) acting as the primary substituent side group, with cosubstitution by phenylphenol (PhPh) and phenylalanine ethyl ester (EPA) to make the final product [1]. Blends of 25% polyphosphazene, 75% PLGA and 50% polyphosphazene, 50% PLGA were …

Peptoid And Antibody-Based Gfp Sensors, Solomon Isu

Graduate Theses and Dissertations

In this work, we have made and characterized a pair of immunobiosensors for detecting the green fluorescent protein (GFP) in an aqueous matrix. An anti-GFP antibody-based biosensor was assembled to detect GFP, while a novel peptoid (N-substituted oligomers of glycine designated as IOS-1) biosensor was also assembled for GFP detection. A quartz crystal microbalance (QCM) gold sensor was used as the supporting substrate for self-assembly of the immunobiosensors. Gravimetric measurements of the QCM gold sensor during immunobiosensor construction and operation were available in real-time using a QCM instrument. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and Fluorescence microscopy were used …

Investigation On The Morphology Of Charge-Transfer Complexes In Low Density Polyethylene, Wade Korf

Master's Theses

Fillers are used ubiquitously throughout the fields of polymer and material science to overcome many inherent limitations to polymeric materials (i.e. poor stiffness or strength) and to expand their potential applications. There is a need to develop controllable particle architectures to better understand fundamental structure-property relationships in particle reinforced polymer composites. Charge-transfer complexes (CTCs) can assemble in situ into various needle and dendritic shapes via simple fabrication processes and at low loading levels. In this study, the effect of tetrathiafulvalene (TTF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) CTC crystallites of various shapes and sizes on composite mechanical properties was investigated in an LDPE …

Thiol-Induced Degradation Of Hydrogels Utilizing Multiresponsive Dithiomaleimides Crosslinkers, Kundu Thapa

Honors Theses

Hydrogels are hydrophilic, three-dimensional materials used as platforms for various biomedical applications such as drug delivery, biosensors, or as scaffolds in tissue engineering. The ability to degrade on demand in response to biological cues is particularly attractive whether dealing with microgels or if one aims to release an active ingredient from a scaffolding material. For instance, many cancer-remediation drug delivery platforms leverage the high concentration of glutathione, a thiol-containing tripeptide, found in cancerous cells. In this work, poly(ethylene glycol) acrylate hydrogels were fabricated using dithiomaleimide (DTM) moieties. DTMs are known to undergo thiol-exchange reactions favoring the dissolution of the hydrogel …