Polymer and Organic Materials Commons^™

Polyethersulfone Thin-Film Nanocomposite Membrane Embedded With Amine-Functionalized Graphene Oxide For Desalination Applications, Ahmed Bahaeldin

Theses and Dissertations

Thin-film nanocomposite (TFN) desalination membranes were prepared based on a polyethersulfone (PES) support, where the polyamide (PA) layer was embedded with amine-functionalized graphene oxide (GO). The effect of adding various concentrations of functionalized and un-functionalized GO on the desalination performance, hydrophilicity, and morphology of the membranes was additionally assessed throughout this work. Scanning electron microscopy (SEM) measurements were used to assess the morphology of the membranes in combination with Brunauer-Emmett-Teller (BET) analysis. Contact angle measurements were used to gauge the hydrophilicity of the synthesized membranes. The membrane with the best desalination performance contained 1x10^-3 wt/vol% of functionalized GO in …

Effect Of Platelet Length And Stochastic Morphology On Flexural Behavior Of Prepreg Platelet Molded Composites, Siavash Sattar, Benjamin Beltran Laredo, Sergii G. Kravchenko, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

Prepreg platelet molding compound (PPMC) can be used to create structural grade material with a heterogeneous mesoscale morphology. The present work considered various platelet lengths of the prepreg system IM7/8552 to study the effect of platelet length on the flexural behavior of PPMC composite. A progressive failure finite-element analysis was used to understand competing failure modes in PPMC with the different platelet length. The interlaminar and in-plane damage mechanisms were employed to describe complex failure modes within the mesostructure of PPMCs. Experimental results of the flexural tests of the PPMC with different platelet length sizes were used to validate the …

Drop Wetting And Sliding On Soft, Swollen Elastomers, Zhuoyun Cai

Theses and Dissertations--Chemical and Materials Engineering

Soft, slippery surfaces have gained increasing attention due to their wide range of potential applications, for example in self-cleaning, anti-fouling, liquid collection, and more. One design approach in creating slippery surfaces is using a swollen elastomer, which is a polymer network swollen with a lubricant. This type of surface may be beneficial for longer-term use than standard lubricant-infused surfaces, and provides a versatile surface with tunable mechanical properties. Hence, understanding the physics of soft surface interactions is important for fundamental soft matter physics, biomaterials, adhesives, and coatings. This research experimentally investigates wetting on soft infused networks, with the aim of …

Enhanced Performance Of 3d Electroactive Polymer Transducers Via Hierarchical Structures, Frederick B. Holness

Electronic Thesis and Dissertation Repository

Conjugated polymers (CPs) are a class of polymers that exhibit a change in size or shape in response to electrical stimuli. The unique combination of electrical and mechanical properties facilitates the fabrication of novel devices in a broad range of applications including: sensors, actuators, and lab-on-a-chip systems. The alternating single and double bonds along the polymer chain of CPs enables their electroactive properties but is also responsible for processability associated with CPs that has limited fabrication methods. Recently a photosensitive CP composite enabling additive manufacturing (AM) of 3D CP structures was developed. However, the introduction of a copolymer for mechanical …

Nanocomposites For Applications In Ultracapacitors Based Energy Storage Systems, Duy Pham, Jake Ivirn, Jacob Dileonardi, Ben Mckinney, Ashish Aphale

Symposium of Student Scholars

Electrochemical capacitors also known as ultracapacitor is a potential technology for modern energy storage due to their high performance of charge capacity and fast charge-discharge rates. The superior performance of ultracapacitors will help to meet demands for energy systems in applications such as transportation. Ultracapacitor device consists of electrodes, a polymeric separator, and an electrolyte. Under the applied voltage, the migration of ions between two porous electrodes from the bulk of the electrolyte governs the performance of such devices. In this work, we present experimental research on the synthesis of different electrode materials using atomically thick graphene and conducting polymers. …

Development Of Electrochemical Sensors For The Detection Of Trace Contaminants, Quang Lam, Ashish Aphale, Duy Pham

Symposium of Student Scholars

Several industrial processes, such as stainless steel fabrication and textiles, produce heavy metal byproducts such as chromium. These heavy metals have detrimental effects on the surrounding environments and humans. Recently, electrochemical-driven sensors have been studied and show great potential in miniaturization while still providing measurements at a low cost. In addition, atomically thin allotropes of carbon, graphene, and graphene oxide have shown remarkable results in producing a highly responsive and selective sensor platform. These results are due to their excellent electrical conductivity, high surface area for utility, and physicochemical stability. The existing challenge for electrochemical-driven sensors is understanding the molecular …

Nanoclays And Curcumin Based Food Packaging Material For Intelligent Food Packaging Applications, Kalpani Y. Perera, Swarna Jaiswal, Amit K. Jaiswal, Shubham Sharma

Articles

Bionanocomposite packaging eco-friendly alternatives with enhanced characteristics. This study aimed to develop a bionanocomposite intelligent packaging. Sodium alginate, gelatin, Curcumin (Cur), glycerol, and Nanoclay (NC) films were prepared. The influences of nanoclay and curcumin on the surface, optical, mechanical, chemical, barrier, and pH-indicating properties were studied. The results showed that the lightness of films was reduced by 1.28 folds compared to NC (control) film, while the yellowness of films increased by 5.82 folds. Film transparency was reduced by 9.3 folds and a 3.46 folds increase in UV barrier properties was observed compared to NC (control) film. The highest tensile strength …

Cold Plasma Technology In Food Packaging, Kalpani Y. Perera, Jack Prendeville, Amit K. Jaiswal, Swarna Jaiswal

Articles

Cold plasma (CP) is an effective strategy to alter the limitations of biopolymer materials for food packaging applications. Biopolymers such as polysaccharides and proteins are known to be sustainable materials with excellent film-forming properties. Bio-based films can be used as an alternative to traditional plastic packaging. There are limitations to biopolymer packaging materials such as hydrophobicity, poor barrier, and thermos-mechanical properties. For this reason, biopolymers must be modified to create a packaging material with the desired applicability. CP is an effective method to enhance the functionality and interfacial features of biopolymers. It etches the film surface allowing for better adhesion …

Exploring The Effect Of Environmental Degradation On The Shape Memory Properties Of Polymers, Jorge Mario Avila

Open Access Theses & Dissertations

A key detriment of the use of polymers by our society is the negative effect this material class has had on the environment. A category of polymers known as shape memory polymers (SMP)s have the ability to return to a programmed original shape form after deformation to a temporary shape by using stimuli such as temperature, electrical pulses and even magnetism. The shape memory effect allows for some polymers to heal if they are damaged. This ability to heal means that components made from these materials can be reused rather than thrown away if they are damaged. The work presented …

Design, Fabrication, And Characterization Of Conjugated Polymeric Electrochemical Memristors As Neuromorphic/Integrated Circuits, Benjamin Grant

All Dissertations

Organic materials are promising candidates for future electronic devices compared to the complementing inorganic materials due to their ease of processability, use, and disposal, low cost of fabrication, energy efficiency, and flexible nature toward implementation as flexible and non-conformal devices.With that in mind, electrochemical materials have been widely demonstrated with commercial use as sensors, displays, and a variety of other electronic devices. As Moore's law predicts the increase in the density of transistors on a chip, the requirement to create either smaller transistors or the replacement of the transistor device entirely is apparent. Memory resistors, coined ``memristor", are variable resistive …

Optimized 3d-Printing Of Carbon Fiber-Reinforced Polyether-Ether-Ketone (Cfr-Peek) For Use In Overmolded Lattice Composite, Ryan C. Ogle

Masters Theses

Current orthopedic implants are overwhelmingly composed from metallic materials. These implants show superior mechanical properties, but this can additionally result in stress shielding due to a modulus mismatch between the bone tissue and implanted device. Polymeric implants reduce this stress shielding effect but have much lower mechanical properties, limiting their use. Polylactic acid (PLA) is a widely used biodegradable thermoplastic polymer, however, its use has been limited by the polymer’s mechanical properties and rapid loss of strength during degradation in vivo. Polyether-ether-ketone (PEEK) is another common biocompatible polymer , with chemical and mechanical properties which make it a popular alternative …

Enhancing The Performance Of Poly(3-Hexylthiophene) Based Organic Thin-Film Transistors Using An Interface Engineering Method, Eyob Negussie Tarekegn

All Dissertations

An original design and photolithographic fabrication process for poly(3-hexylthiophene-2, 5-diyl) (P3HT) based organic thin-film transistors (OTFTs) is presented. The structure of the transistors was based on the bottom gate bottom contact OTFT. The fabrication process was efficient, cost-effective, and relatively straightforward to implement. Current–voltage (I-V) measurements were performed to characterize the primary electronic properties of the transistors. The measured mobility of these transistors was significantly higher than most results reported in the literature for other similar bottom gate bottom contact P3HT OTFTs. The higher mobility is explained primarily by the effectiveness of the fabrication process in keeping the interfacial layers …

Hierarchical Structure And Material Integration For Electrocatalytic Co2 Reduction, Hamed Mehrabi

Graduate Theses and Dissertations

CO2 released by the combustion of fossil fuels is driving significant changes to the earth’sclimate. The natural cycle for removing CO2 from the atmosphere, namely photosynthesis, cannot keep up with the rate at which it is being added. Developing engineering approaches to remove CO2 from the atmosphere is becoming essential to reduce these effects. Removal leads to further issues of carbon sequestration and favorable CO2 reuse strategies, including the electrochemical transformation of recovered CO2 to useful products such as fuels and materials. Copper is an important electrocatalyst for the CO2 reduction reaction (CO2RR) because of its unique capability for producing …

Sustainable Material For Urea Delivery Based On Chitosan Cross-Linked By Glutaraldehyde Saturated Toluene: Characterization And Determination Of The Release Rate Mathematical Model, Jayanudin Jayanudin, Retno S. D. Lestari, Indar Kustiningsih, Dandi Irawanto, Rozak Rozak, Reyonaldo L. A. Wardana, Fakhri Muhammad

Karbala International Journal of Modern Science

The aims of this study were to characterize the urea-loaded chitosan microspheres and determine the release kinetic constants and diffusion coefficients. An emulsion cross-linking method was used to prepare the urea-loaded chitosan microspheres. Urea was dissolved in a solution of chitosan then put into vegetable oil and stirred to form an emulsion. Glutaraldehyde saturated toluene (GST) was added into the emulsion dropwise while continuously stirring for the solidification process. Chitosan microspheres filled with urea were washed, dried, and then analyzed. Characterization of the urea-loaded chitosan microspheres was conducted using a scanning electron microscope (SEM), Raman spectroscopy, X-ray diffraction, and particle …

Biodegradable Active Bio-Nanocomposite Film For The Enhanced Shelf Life Of Tomatoes, Kalpani Y. Perera, Shubham Sharma, Brendan Duffy, Amit K. Jaiswal, Swarna Jaiswal

Articles

The increased environmental pollution has led to finding sustainable solutions for non-renewable plastic-based food packaging materials. Thus, the use of biomaterial-based packaging material has become an immense trend. This work aims at developing an antimicrobial biodegradable chitosanalginate bio-nano composite film with TiO2 nanoparticle (NPs) for food packaging applications. The film was developed by a solution casting method. The chemical, mechanical, thermal, barrier, antimicrobial, and biodegradable properties of the packaging films were evaluated. Packaging studies were performed for 15 days for cherry tomatoes. The designed packaging material had enhanced the mechanical properties with a significantly (p < 0.05) higher tensile strength of 15.76 folds and 2 fold higher elongation at break. The UV barrier properties increased by 88.6%, while the film transparency decreased by 87.23%. Molecular interaction of N-H covalent bonds was observed between alginate and chitosan together with TiO2 NPs. The developed bio-nano composite film showed antimicrobial activity against foodborne pathogens E. coli, S. aureus, S. typhi, and L. monocytogene with a log reduction of 7.08, 7.28, 6.04 & 6.02 log CFU/ml respectively at 24 hours incubation period. The film was completely biodegraded and a weight loss of 89.06% was observed in bio-nanocomposite film during the 3 months. Shelf-life estimation of cherry tomato using developed packaging films showed an increase in the shelf-life up to 8 days with stable pH, total soluble solids, and weight with no bacterial growth when packaged with prepared film. Owing to their improved mechanical, UV barrier, antibacterial, and biodegradability, the prepared active bio-nano composite packaging films could be considered a potential candidate for fruit packaging.

Sodium Alginate, Nanoclay And Curcumin Based Food Packaging Material For Intelligent Food Packaging Applications, Kalpani Y. Perera, Máille Hopkins, Shubham Sharma, Brendan Duffy, Amit K. Jaiswal, Swarna Jaiswal

Articles

Bionanocomposite food packaging contains materials of biological origin which display high-performance activity when compared to biopolymers and are eco-friendly alternatives to conventional packaging materials. Intelligent packaging monitors the condition of the food or environment surrounding the food and communicates changes to the consumer. This study aimed to develop a bionanocomposite intelligent packaging material by utilising sodium alginate, nanoclay and curcumin. Sodium alginate (2 W/V% SA) film incorporated with 0.3 W/V% curcumin (Cur), glycerol, and nanoclay (NC) in various concentrations (0, 0.5, 1 and 2 W/V %) was prepared using the solvent casting method. The influences of nanoclay and curcumin on …

Synthesis And Assembly Of Polymer Materials At Interfaces, Xiaoshuang Wei

Doctoral Dissertations

The overarching goal of the thesis is to understand growth and assembly of polymer materials at interfaces. Chapter 2 and Chapter 3 study simultaneous polymer growth and assembly at fluid interfaces, where in-situ photopolymerization and vapor phase deposition were utilized to grow polymers, respectively. Chapter 4 leverages capillary condensation to pattern polymer growth at solid substrates.

Chapter 1 provides background information on polymer materials at interfaces, and vapor phase deposition method (initiated chemical vapor deposition, iCVD) to grow polymers. This chapter also reviews polymer thin film wetting, and colloidal assemblies at interfaces.

In Chapter 2, we demonstrate the preparation …

Bio-Based Food Packaging Material For Intelligent Food Packaging Applications For Chicken Fillets, Kalpani Y. Perera, Amit K. Jaiswal, Swarma Jaiswal, Shubham Sharma

Articles

Bionanocomposite packaging is made up of bio- based materials that have high performance activity and are ecologically sustainable alternatives to packaging made of synthetic polymers. Intelligent packaging retains track of the state of the food and the environment in which it is stored, and communicates relevant changes to the consumer through visualization or other methods. The aim of this study was to develop a bionanocomposite intelligent packaging material by utilising sodium alginate, gelatin, nanoclay and curcumin. Sodium alginate, gelatin film incorporated with Curcumin (Cur), and Nanoclay (NC) in various concentrations (0% W/V, 0.5% W/V, 1% W/V and 1. 5% W/V) …

Biobased Packaging Materials From Cellulose Nanofibrils Produced From Virgin Wood Pulp Or Recycled Cardboard Pulp, Md Ikramul Hasan

Electronic Theses and Dissertations

Self-standing cellulose nanofibril (CNF) films are regarded as one of the promising alternatives to current petroleum-based packaging materials. The mechanical and barrier properties of CNF films are not yet up to the mark for certain applications, especially at high relative humidity. Those properties of CNF films can be tuned by the drying methods of films, degree of fibrillation, cross-linking, and controlled shrinkage. A comprehensive understanding of these processes and their influence on the structure and properties of CNF films have been presented in this thesis.

First, we prepared CNF films from CNF suspensions with two different degrees of fibrillation- standard …

Contact Dewatering Of Cellulose Nanofibers For Biopolymer Composite Applications, Alexander Collins

Electronic Theses and Dissertations

Cellulose Nanofibrils (CNFs) are promising materials for reinforcement of polymer matrices attributable to their impressive physical and mechanical properties, as well as their biodegradability. However, the utilization of these materials in composites is made challenging by the water content of CNF slurries, the tendency of CNFs to agglomerate as they dry, and incompatibility between hydrophilic CNFs and hydrophobic polymer matrices. The most commercially viable drying methods to produce small-scale dry CNFs, such as spray drying, are very energy intensive, can only dry the materials down to micron-scale agglomerates, and do not preserve fibrillar aspect ratios. “Contact dewatering,” or the removal …

Numerical Modeling Of Localized Heating In Continuous Fiber Reinforced Thermoplastic Laminates, James T. Gayton

Electronic Theses and Dissertations

The manufacturing of continuous fiber-reinforced thermoplastic (CFRTP) laminates requires the application of heat and pressure. Standard CFRTP manufacturing methods like thermoforming take a global approach to manufacturing, where the whole part is heated and undergoes a forming process. There is an opportunity to develop advanced manufacturing methods based on localized heating and deformations of consolidated stock. This thesis provides a localized heating method via networks of resistive heating elements embedded within the laminate and a means to evaluate that method.

Typical heating methods for CFRTP laminates include infrared and convective ovens or surface contact heaters. They have the same drawbacks …

Investigating Features And Output Correlation Coefficient Of Natural Fiber-Reinforced Poly(Lactic Acid) Biocomposites, Andreas Federico, Siti Norasmah Surip, Wan Nor Raihan Wan Jaafar, Jaka Fajar Fatriansyah, Agrin Febrian Pradana

Journal of Materials Exploration and Findings (JMEF)

Polylactic acid (PLA) material has the potential to be applied in various industrial fields, but this material has shortcomings in terms of mechanical properties, especially mechanical strength, due to brittleness nature of PLA. The manufacture of PLA composite material with the addition of natural fibers as a reinforcing phase is one of the methods to increase the impact strength and maintain the biodegradable properties of the material. However, in theory, there are many factors that affect the mechanical properties of composite materials, thus making the mechanical properties of composites more complex than monolithic materials. The mechanical properties of these composite …

How Dynamic Bond Results In The Unique Viscoelastic Behavior Of The Associating Polymers, Sirui Ge

Doctoral Dissertations

Associating polymer is a special kind of polymer possessing transient reversible bonds in addition to the conventional covalent bonds. The reversible bonds provide unique dynamics and fascinating viscoelastic properties, resulting in attractive applications for these polymers, such as self-healing and shape memory materials. Despite many years of studies, the understanding of dynamics of polymers with reversible bonds, especially on molecular level, is still in the rudimentary stage, preventing the rational design of the potential novel functional materials based on associating polymers. In this dissertation, we provide a detailed and quantitative understanding of the dynamics and viscoelastic properties of associating polymers. …

Functional Bottlebrush Polymer Additives For Thin Films And Coatings, Travis S. Laws

Doctoral Dissertations

Bottlebrush polymers are a class of highly branched polymers consisting of polymeric side chains that are densely grafted to a linear backbone. Their highly branched architecture results in surface enrichment across a broad range of materials. The goal of my research has been centered around the design of functional bottlebrush polymers and their use as surface active additives in blend films and coatings.

In the first chapter, we examine the segregation behavior of polystyrene bottlebrushes that are blended with linear polystyrene. We systematically vary the lengths of the bottlebrush backbone (Nb), side-chain (Nsc), and the linear matrix (Nm) in order …

3d Printed Multicomponent Polymer Based Materials Via Hybrid Filaments: Fabrication And Characterization, Erik Antonio

All Dissertations

Additive manufacturing, also known as 3D printing, promises a manufacturing revolution for both industry and academic circles. One of the most widely used method of 3D printing is Fused Deposition Modeling (FDM) or Fused Filament Fabrication (FFF), which requires a thermoplastic filament to be directed towards a heating block and then deposited via extrusion layer by layer to produce a finished part. However, there are significant issues with this technology, mainly a limitation on the materials available for use and mechanical property deficiencies when compared to traditional manufacturing. These issues are brought about by the temperature limited nature of the …

Characterization Of Thermal Gelation Properties In Bioresorbable Thermally Activated Hydrogel Polymers For Hernia Surgery Applications, Alexander Mayfield

All Theses

Hydrogel adhesives are a new class of materials with excellent biocompatibility, which makes them very attractive for biomaterial applications. It has been previously shown that Tetronic T1107, a four-arm poly (propylene oxide)-poly (ethylene oxide) (PPO-PEO) block copolymer, is useful as a chemical crosslinking thermo-responsive hydrogel for bioadhesive applications. The end groups of this polymer are modified with acrylate and N-hydroxysuccinimide (NHS) functional groups. The acrylate end group gives the polymer cohesive properties with long-range chemical crosslinking using dithiothreitol (DTT), while the NHS end group gives the polymer adhesive properties through bonding with amines found in organic tissue. It was found …

Fabrication And Non-Covalent Functionalization And Characterization Of Graphene-Based Devices On Novel Substrate Cadmium Trithiophosphate (Iv) — Cdps, Abayomi Omotola Omolewu

Graduate Theses and Dissertations

With graphene at the center of several application areas such as sensing, circuits, high-frequency devices for communication systems, etc., it is crucial to understand how the intrinsic properties of devices made from graphene and other materials like platinum and palladium nanoparticles affect the performance of such devices for the specific application area. Many graphene-based devices for different application areas have focused mainly on the material composition of the graphene-based devices and how it affects performance parameters for the specific application. However, it would be insightful to understand how the intrinsic electrical properties of the graphene devices for different applications affect …

Development Of A Decellularized Hydrogel Composite And Its Application In A Novel Model Of Disc-Associated Low Back Pain In Female Sprague Dawley Rats, David Lillyman

Biological Systems Engineering--Dissertations, Theses, and Student Research

Chronic low back pain is a global socioeconomic crisis compounded by an absence of reliable, curative treatments. The predominant pathology associated with chronic low back pain is degeneration of intervertebral discs in the lumbar spine. During degeneration, nerves can sprout into the intervertebral disc tissue and be chronically subjected to inflammatory and mechanical stimuli, resulting in pain. Pain arising from the intervertebral disc, or disc-associated pain, is a complex, multi-faceted disorder which necessitates valid animal models to screen therapeutics and study pathomechanisms of pain.

While many research teams have created animal models of disc degeneration, the translation of these platforms …

Bbt Acoustic Alternative Top Bracing Cadd Data Set-Norev-2022jun28, Bill Hemphill

STEM Guitar Project’s BBT Acoustic Kit

This electronic document file set consists of an overview presentation (PDF-formatted) file and companion video (MP4) and CADD files (DWG & DXF) for laser cutting the ETSU-developed alternate top bracing designs and marking templates for the STEM Guitar Project’s BBT (OM-sized) standard acoustic guitar kit. The three (3) alternative BBT top bracing designs in this release are
(a) a one-piece base for the standard kit's (Martin-style) bracing,
(b) 277 Ladder-style bracing, and
(c) an X-braced fan-style bracing similar to traditional European or so-called 'classical' acoustic guitars.

The CADD data set for each of the three (3) top bracing designs includes …

Super-Hydrophobic Hybrid Coatings Preparation Used By Methyltrithoxysilane (Mtes) And Tetraethylorthosilicate(Teos), Quanwei Li

International Conference on Durability of Concrete Structures

超疏水材料由于其优异的疏水自洁性能，在航空航天、海洋工程、除冰防腐等领域具有广阔的应用前景。本文采用简单的溶胶-凝胶制备超疏水涂层。 . 以甲基三乙氧基硅烷（MTES）和原硅酸四乙酯（TEOS）为前驱体，水解缩合后形成粗糙结构，1H,1H,2H,2H-全氟癸基三乙氧基硅烷（FAS）为低表面能的表面活性剂，系统研究了各自的最佳配比零件。涂层的疏水性和形貌分别通过水接触角测量、扫描电子显微镜（SEM）表征。同时，其官能团通过红外光谱表征。基于大量的实验和优化测试，