Materials Science and Engineering Commons^™

O-Xloratsetiltimol Sintezi Va Uni Kimyoviy Modifikatsiyalash, Azimjon U. Choriev, Anvar K. Abdushukurov, Ilyos U. Normurodov, Sarvinoz K. Mirzayeva

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study is to develop a convenient method for the synthesis of O-chloroacetylthymol and to propose the mechanism of the O-chloroacetylation reaction. Thin-layer chromatography of chloroacetylation and nucleophilic substitution reaction products was studied and their composition was confirmed by reference substances. Nucleophilic exchange reactions of O-chloroacetylthymol with sodium oxalate, sodium tartrate, potassium rhodanides were studied. Favorable conditions for carrying out the nucleophilic exchange reaction were searched and 3 new substances unknown in the literature were synthesized. The structure of the synthesized substances was proved by IR and NMR spectra.

Polyvinyl Alcohol–Red Cabbage Nanofibers As Ph-Responsive Freshness Sensors For Advanced Food Packaging Technology, Foliatini Foliatini, Singgih Wibowo, Henny Rochaeni, Suhartini Suhartini, Fachrurrazie Fachrurrazie, Arzzaq Imanda Prianditya, Pradnadia Putri Hadriansyah, Naura Athira Putri Siregar, Novi Nurpadilah, Putri Alfiani, Maudi Rahim, Endah Sriwahyuni

Makara Journal of Science

The development of innovative food packaging technologies, particularly those capable of monitoring freshness, has become increasingly important in the food industry. This research explores the development of a pH-responsive freshness sensor using polyvinyl alcohol–red cabbage (PVA/RC) nanofibers. The nanofibers are fabricated through the electrospinning technique and meticulously analyzed via scanning electron microscopy, Fourier-transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC). The results underscore the fine structure of the nanofiber matrix, with an average diameter of ~68 nm. FTIR analysis substantiates the presence of anthocyanin compounds from RC within the PVA/RC nanofibers, which confirms the integration of beneficial components into …

Experimental Examination Of Enhanced Nanoceramic-Based Self-Cleaning Sprays For High-Efficiency Hydrophobic Photovoltaic Panels, Iman El-Mahallawi, Merna Abdrabo, Ahmed Elkaseer Prof., Engy Elshazly, Mohamed S. El-Deab

Renewable Mechanical Energy

Dust deposition poses a significant challenge in the implementation of photovoltaic panels (PV) especially in hot and dusty environments, such as the Middle East and North Africa (MENA) region. This issue leads to progressive degradation of PV efficiency and output power. In this context, this research work aims to improve PV performance by developing self-cleaning sprays as a preventative solution. Different concentrations of SnO2 and TiO2 nanoceramics were dispersed in isopropyl alcohol solvent to reduce the mixture’s viscosity and facilitate smooth spraying on solar panels, whose efficiency was continually assessed in outdoor conditions. Although less commonly used for this application, …

Investigation Of Temperature, Solution Strength, And Applied Stress Effects On Cation Exchange Processes In Different Geosynthetic Clay Liner Products, Kendra Fuller

Master's Theses

An extensive laboratory test program was conducted to analyze and compare the cation exchange processes in three different varieties of sodium bentonite (Na-B) geosynthetic clay liners (GCLs) over increased conditioning durations up to 32 days and investigate the effects of temperature, solution strength, and applied stress. The goal of this test program was to establish whether the variables of temperature, solution strength, and applied stress improved or degraded the engineering properties of GCLs in laboratory testing and municipal solid waste (MSW) landfill applications. The GCLs were conditioned in liquids of increasing ionic strength, using deionized water and 2, 50, and …

Thermomechanical Analysis Of Biomass Plastic Composite (Bpc), Solomon Chijioke Madu, Victor Sunday Aigbodion, Ikechukwu Ike-Eze

Makara Journal of Technology

High-performance electrical insulation material can be manufactured using biomass plastic composite (BPC), which is a new type of composite material that is either made up of one or a combination of natural plant fibers/particulates, such as bamboo, cellulose fiber, rice husks, or hemp, and thermoplastic granules. In this study, the BPC composite material that was developed comprised polyethylene (PE), rice husk, and oyster shell. The results of the study showed a significant optimal improvement in the morphological, thermodynamic, and mechanical properties during the addition of 20% to 30% biomass particulates (i.e., rice husk and oyster shell). The thermogravimetric analysis, storage …

Investigation Of Distributed Additive Manufacturing For 3d Printed Headband Component During Global Supply Chain Disruptions, Elizabeth M. Mamros, Saketh Kantipudi, Matthew C. Eaton, Jinjin Ha, Brad L. Kinsey

Faculty Conference Papers and Presentations

During the COVID-19 global pandemic, a shortage of personal protective equipment (PPE) occurred. Manufacturers of these critical products were unable to keep up with the growing demands as the situation evolved. Most face shields, a common type of PPE, include a headband component to provide the appropriate fit for the user and curvature for the clear face shield attachment. To mitigate this shortage in the local region, the Portsmouth Naval Shipyard (PNSY) generated a computeraided design (CAD) file for the headband component and asked the University of New Hampshire (UNH) to manufacture it with all available 3D printers, including printers …

Development And Structural Origin Of Stretchable Semiconducting Polymers And Composites, Yunfei Wang

Dissertations

Stretchable semiconductors are pivotal in advancing wearable and implantable electronics, with those boasting both high stretchability and self-healing capabilities being especially significant for a myriad of wearable applications. In this dissertation, we developed an extremely soft, highly stretchable, and self-healing elastomer based on H-bonding crosslinked amide-functionalized polyisobutylene (PIB-amide). When blended with a high-performance conjugated diketopyrrolopyrrole (DPP-T) polymer, the composite exhibits unprecedented stretchability, exceptionally low elastic modulus, and an innate ability to self-heal at room temperature.

The morphology of conjugated polymer/elastomer semiconducting composites have significant impacts on electrical and mechanical properties Further investigations focused on manipulating the phase separation size in …

Fabrication And Characterization Of Lignin–Pva Hydrogels With Tunable Network Structures, Keturah Bethel

All Dissertations

The ability to directly tune the crosslinked network structure of hydrogels is crucial for their functional applications in various fields, such as water filtration, protein separation, and tissue engineering. By controlling the crosslink density of the hydrogel, one can directly alter the mesh size – i.e., the end-to-end distance between crosslink junctions – and, subsequently, directly alter the hydrogel performance. This work discusses the fabrication and characterization of soft composites containing the biopolymer, lignin, are discussed. Precisely, physically-crosslinked composite lignin–Poly(vinyl alcohol) (PVA) hydrogels were fabricated via the freeze-thaw (F/T) pathway, whereby solutions containing specified amounts of PVA and lignin were …

Exploring The Synthesis Of Biobased And Chemically Recyclable Polysulfone Using Imine Chemistry, Vitasta Jain

All Dissertations

Plastic waste poses a major problem because of the chemical stability of these materials, leading to their accumulation in the environment and the leaching of toxic chemicals during their slow decomposition. Additionally, the use of depleting petroleum reserves for synthesis has made for an unsustainable production and risks due to use of chemicals hazardous to the environment and the individuals exposed to it.

To address these concerns, researchers have explored biobased feedstock and incorporating chemical recycling capabilities for a closed loop, sustainable process. One promising feedstock is lignin with its abundant functional groups that can be modified and utilized to …

Physics-Informed Machine Learning Methods For Inverse Design Of Multi-Phase Materials With Targeted Mechanical Properties, Yunpeng Wu

All Dissertations

Advances in machine learning algorithms and applications have significantly enhanced engineering inverse design capabilities. This work focuses on the machine learning-based inverse design of material microstructures with targeted linear and nonlinear mechanical properties. It involves developing and applying predictive and generative physics-informed neural networks for both 2D and 3D multiphase materials.

The first investigation aims to develop a machine learning method for the inverse design of 2D multiphase materials, particularly porous materials. We first develop machine learning methods to understand the implicit relationship between a material's microstructure and its mechanical behavior. Specifically, we use ResNet-based models to predict the elastic …

Synergistic Strategies In Hybrid Mxed Matrix 3d Printing Of Thermoplastics & Thermosets: Design, Manufacturing, And Materials Development., Saleh Akram Khanjar

Electronic Theses and Dissertations

Composite manufacturing and mixed matrix structures have been produced using traditional manufacturing processes for various industrial applications due to their high mechanical properties to material weight and cost ratio. However implementation of composite and mixed matrix manufacturing with advanced manufacturing such as additive manufacturing is limited due to the hardware limitations of current 3d printing technologies and materials available for 3D printing applications. This work has developed and investigated a new hybrid 3D printing manufacturing process utilizing a variety of material systems (thermoplastic – thermoset, thermoplastic – thermoplastic, thermoset – thermoset, thermoplastic – thermoplastic – thermoset). This study developed thermoplastic …

Development And Processing Of Shape Memory Polymer Composites (Smpcs) For Application In Structural Robotics And Robotic Sensors., Kavish Sudan

Electronic Theses and Dissertations

Shape Memory Polymers (SMPs) have attracted significant attention since their introduction in the 1980s due to their remarkable ability to regain their original shape from a temporarily deformed state when exposed to an external stimulus, typically heat. This shape memory effect, driven by thermal transitions such as the glass transition temperature (T_g) or melting temperature (T_m), has made SMPs highly attractive for applications in soft robotics, aerospace, and biomedical devices. However, SMPs face challenges such as limited mechanical strength, thermal stability, and electrical conductivity, which hinder their broader adoption in advanced applications. To address these challenges, …

Performance And Enhanced Efficiency Induced By Cold Plasma On Sapo-34 Membranes For Co2 And Ch4 Mixtures, Fnu Gorky, Vashanti Storr, Grace Jones, Apolo Nambo, Jacek B. Jasinski, Maria L. Carreon

Chemical Engineering Faculty Publications and Presentations

In this study, we investigate the influence of cold-plasma-induced enhanced performance and efficiency of SAPO-34 membranes in the separation of CO₂ and CH₄ mixtures. Placing the herein presented research in a broader context, we aim to address the question of whether cold plasma can significantly impact the membrane performance. We subjected SAPO-34 membranes to plasma mild disturbances and analyzed their performance in separating CO₂ and CH₄. Our findings reveal a notable enhancement in membrane efficiency and sustained performance when exposed to cold plasma. The pulsed plasma separation displayed improved structural integrity, and the experimental results …

Chemical Recycling Of Bio-Based Polyurethane Foams: Evaluating Bio-Based Glycols In Comparison To Petroleum-Based Glycols, Anirudh Thorbole Mr.

Electronic Theses & Dissertations

The paradigm shift towards bio-based polyurethane foams (bio-PUF) has significantly increased post-consumer waste. To address this issue, this research represents a novel approach to enhance sustainable development in the recycling industry by replacing traditional petroleum-based glycols with sustainable bio-based alternatives. This study explores the glycolysis of bio-PUF using bio-based SG-522 glycol and polyethylene glycol (PEG) for comparison. The findings from this research as outlined, reveal no significant differences in depolymerization time between the two glycols, achieving proper depolymerization and high recovery yields of over 95% after solvent purification. Comprehensive FT-IR and NMR analyses confirmed the successful degradation of bio-PUF and …

Synthesis, Crystal Structure, Hirshfeld Surface And Void Analysis Of 2-Amino-1h-Benzimidazolium 2-Hydroxybenzoate, Salmon M. Mukhammadiev, Daminbek A. Ziyatov, Zuhra Ch. Kadirova, Jamshid M. Ashurov, Shahlo Sh. Daminova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is determination of crystal structure and Hirschfeld surface void analysis for many intermolecular interactions in the crystal structure of 1,3-dihydro-2H-benzimidazole-2-iminium-2-hydroxy-5-sulfobenzoate.. For the first time, a new organic salt containing organic benzimidazolium cations and sulfosalicylic anions was synthesized and structurally characterized. Hirshfeld surface analysis confirm that in the crystal shape most remarkable contacts are H∙∙∙O (38%) and H∙∙∙H (29.7%) There are some π–π stacking interactions in the crystal shape.

Synthesis Of Cationite Based On Indene, A Secondary Product Of Hydrocarbons Pyrolysis, Saidmansur Sh. Saidobbozov, Suvonkul E. Nurmanov, Dilorom H. Mirkhamitova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the study is extraction of the indene from pyrolysis oil obtained from the pyrolysis of hydrocarbons at the Ustyurt gas processing plant. Indene is isolated by rectification from the composition of pyrolysis oil formed as a by-product of the process of hydrocarbons pyrolysis at the Ustyurt gas processing plant. Polymethyleneindenesulfocationite was synthesized on the basis of isolated indene, and its structure and physicochemical properties were determined. Chromatomass spectrum of pyrolysis oil was obtained and analyzed. The indene fraction and the synthesized polymethyleneindenesulfocationite were analyzed using IR spectroscopy and SEM (scanning electron microscopy). Thermal analysis of cationite was …

Preparation Of Keratin-Containing Protein Compounds From Chickens Feathers Using Hydrochloric Acid, Dilnozakhon I. Tursunova, Oytura S. Maksumova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is the preparation of keratin-containing protein compounds from poultry processing waste by hydrolysis with hydrochloric acid, including treatment of the protein with 5% H₂O₂. The process of cleaning feather raw materials using water, liquid soap, NaClO₃, C₂H₅OH, and H₂O_2, and the reaction of its hydrolysis with an aqueous solution of HCl have been studied. The influence of temperature and reaction duration on the hydrolysis process was studied, and its optimal mode was established. It has been shown that the process of …

Poly(Thioether) Thermosets With Gated Photodegradation, Surabhi Jha

Dissertations

Photodegradable polymer networks are attractive due to the precise spatiotemporal control and large-area applicability of light. Chemical linkages that enable these polymer networks to be photo-responsive, also hinder their applicability in ambient light. Photostable and photodegradable networks have recently been reported to overcome this challenge by combining other stimuli with light for degradation. We report the design of a network that responds to a simultaneous, dual stimulus for photodegradation. We design poly(thioether acetal) networks with benzylidene acetal moieties that are known to undergo β-scission in the presence of free thiols. By blocking these free thiols with a thermally labile protecting …

Performance Evaluation Of Asphalt Binder Modified With Recycled Plastics, Abeeb G. Oyelere

Graduate Theses and Dissertations (2019 - present)

The surge in the production of plastic waste has become a pressing global environmental issue. To address this, repurposing plastic waste to modify asphalt binders in asphalt pavement is being explored This study investigates the potential of recycled high-density polyethylene (rHDPE) and recycled polypropylene (rPP) as asphalt binder modifies to improve pavement performance and sustainability while mitigating plastic waste's adverse environmental impacts. Laboratory investigations were conducted to assess the rheological performances as well as the compatibility of rHDPE and rPP-modified asphalt. Additionally, the impact of aging and mixing temperature on rheological performance was investigated. Experimental results indicated that adding these …

Carbon-Based Nanocomposite Membranes For Membrane Distillation: Progress, Problems And Future Prospects, Chhabilal Regmi, Yuwaraj K. Kshetri, S. Ranil Wickramasinghe

Chemical Engineering Faculty Publications and Presentations

The development of an ideal membrane for membrane distillation (MD) is of the utmost importance. Enhancing the efficiency of MD by adding nanoparticles to or onto a membrane’s surface has drawn considerable attention from the scientific community. It is crucial to thoroughly examine state-of-the-art nanomaterials-enabled MD membranes with desirable properties, as they greatly enhance the efficiency and reliability of the MD process. This, in turn, opens up opportunities for achieving a sustainable water–energy–environment nexus. By introducing carbon-based nanomaterials into the membrane’s structure, the membrane gains excellent separation abilities, resistance to various feed waters, and a longer lifespan. Additionally, the use …

Optimizing The Expression Of Polyethylene Terephtalate Hydrolase-Encoding Synthetic Gene In Escherichia Coli Arctic Express (De3), Jocelyn Nataniel, Maria Ulfah, Dini Achnafani, Niknik Nurhayati, Gabriela Christy Sabbathini, Sri Rezeki Wulandari, Abinawanto Abinawanto, Is Helianti

Makara Journal of Science

The waste of polyethylene terephthalate (PET) plastic waste in Indonesia is a pressing concern due to its slow degradation and potential environmental damage. One promising solution is to utilize polyethylene terephthalate hydrolase from Ideonella sakaiensis (IsPETase), an enzyme that specifically degrades PET. However, inducing the expression of IsPETase synthetic gene in Escherichia coli BL21 (DE3) has been challenging because much of it remains insoluble. This study aimed to express IsPETase in E. coli Arctic Express (DE3) and optimize the conditions to enhance its production. First, pET22b(+)pelB-IsPETase was inserted into E. coli Arctic Express (DE3). The …

Effect Of Oxidation Of Graphene On Agglomeration And The Mechanical Properties Of Thermosetting Resins, Matthew A. Reil

Electronic Theses and Dissertations

Thermosetting resins are used extensively worldwide in applications ranging from adhesives to structural components. However, these resins generally fail in a brittle fracture mode which is undesirable in most situations. Graphene (G) and its derivatives have been considered as additives to epoxy for material property enhancement and varied results have been reported in the literature. In this work, the effects of the oxidation of G to graphene oxide (GO) on polymer interactions and plate agglomeration were studied by classical molecular dynamics (MD). Results from those simulations concluded that agglomerates were likely present in all G-based nanocomposites. The effect of these …

Predicting Rheology Of Uv-Curable Nanoparticle Ink Components And Compositions For Inkjet Additive Manufacturing, Cameron D. Lutz

Master's Theses

Inkjet additive manufacturing is the next step toward ubiquitous manufacturing by enabling multi-material printing that can exhibit various mechanical, electronic, and thermal properties. These characteristics are realized in the careful formulation of the inks and their functional materials, but there are many constraints that need to be satisfied to allow optimal jetting performance and build quality when used in an inkjet 3-D printer. Previous research has addressed the desirable rheology characteristics to enable stable drop formation and how the metallic nanoparticles affect the viscosity of inks. The contending goals of increasing nanoparticle-loading to improve material deposition rates while trying to …

A Comprehensive Investigation Of The Influence Of Geometric Structure On The Shape Memory Performance Of Nafion, Jade Thomas

Physics Undergraduate Honors Theses

While perfluorosulfonic acid (PFSA) membranes have primarily been used in fuel cells due to their chemical, thermal, and mechanical stability, one PFSA, Nafion, boasts two unique characteristics: a broad glass transition (~55 °C to 130 °C) and a temperature-persistent electrostatic network. The combination of these two characteristics endows Nafion with exceptional shape memory properties – the ability of a material to morph and transform into pre-programmed shapes when exposed to an external stimulus – with enhanced permanent shape memorization, and a potentially near-infinite number of temporary shape memorization. This study focused on expanding the base of knowledge surrounding Nafion’s shape …

A Comprehensive Investigation Of The Influence Of Geometric Structure On The Shape Memory Performance Of Nafion, Jade Thomas

Mechanical Engineering Undergraduate Honors Theses

While perfluorosulfonic acid (PFSA) membranes have primarily been used in fuel cells due to their chemical, thermal, and mechanical stability, one PFSA, Nafion, boasts two unique characteristics: a broad glass transition (~55 °C to 130 °C) and a temperature-persistent electrostatic network. The combination of these two characteristics endows Nafion with exceptional shape memory properties – the ability of a material to morph and transform into pre-programmed shapes when exposed to an external stimulus – with enhanced permanent shape memorization, and a potentially near-infinite number of temporary shape memorization. This study focused on expanding the base of knowledge surrounding Nafion’s shape …

Release Of Small Molecules From Rubber: Effects Of Materials Properties, Mechanical Loading And Molecular Interactions, Yongcan Du

All Dissertations

Release of small molecules from polymeric materials has wide applications in the delivery systems of active molecules such as drug, fragrance, and semiochemical. Rubber materials are good candidates for the excipients of those systems due to properties such as good flexibility, permeability, and biocompatibility. Factors like material properties, mechanical loading, and molecular interactions may affect the release of small molecules in those systems. Therefore, understanding how those factors affect the release is key to the formulation, design, and evaluation of those systems.

To study the effects of materials properties, vulcanized natural rubber sheets with different crosslink densities, loaded with small …

Characterization Of Platinum On Carbon Nanoparticles Selectively Coated With Titanium Nitride (Tin), Matthew Maramo

Honors Scholar Theses

Proton exchange membrane fuel cells are a promising low-carbon technology that still face problems including low durability during their normal operation cycles. At the cathode, the carbon supports of the catalysts may corrode. Atomic layer deposition of titanium nitride is performed on prepared catalyst layer samples. The purpose of the deposition is to create a thin film over the carbon supports to reduce carbon support corrosion and improve the lifespan of the fuel cell. Sheet resistances and contact angles are measured for the samples before and after the deposition, although some samples did not receive the deposition and post-deposition characterization …

Investigation Of Domain Formation During Phase Separation In A Mixture Of Flexible And Rigid Biopolymers, Steven Huntley

All Theses

Complex fluids and heterogenous mixtures composed of multiple types of polymers are found throughout industrial and biological fluid systems. For example, extrusion based additive manufacturing systems pass dense mixtures of polymers through the extrusion heads to deposit composite polymeric materials. In cells, active and complex mixtures of biopolymers self-organize into assemblies that perform critical physiological functions.

Polymers in dense solutions undergo phase separation as a result of differences in physiochemical properties. A few examples of these properties include charge, structure, rigidity, and hydrophobicity. We observe the formation of polymer domains composed of rigid and a flexible biopolymer species that phase …

Green Chemistry Design Of Epoxies From Biomass For Circular Economy, Kavya Ganesan

All Dissertations

The commercial epoxies market in automobiles has been growing mainly in terms of usage as automotive coatings and lightweight composite structures manufacturing. Most of these commercial epoxies are bisphenol-based. Bisphenol-based epoxies are a class of high-performance polymer materials that, when cured, yield thermosets with high mechanical, thermal and chemical resistance properties. Roughly, North America produces around 123 billion pounds of these epoxies which are used in various industrial applications like coatings, composites, structural parts, automotive, electronics, construction etc. These epoxies are mainly manufactured from bisphenol-A (BPA) and epichlorohydrin (EPH). These raw materials are sourced from fossil fuel resources and are …

Additive Manufacturing With Bioresorbable Polymers: Process-Structure-Property Relationships For Biomimetic Tissue Scaffolds, Clayton Joseph Culbreath

All Dissertations

Tissue engineering has a base requirement of scaffold structures to support cell growth, proliferation, and regeneration. However, attempts to use artificial scaffold structures have often fallen short of clinical needs to justify the change away from the established, biologic-based current standard of care. Based on the limited number of successful tissue scaffolds produced by material extrusion modes of additive manufacturing, fused filament 3d printing and electrospinning, critical design specifications for a tissue scaffold are six minimum requirements: 1) biocompatibility, 2) porosity, 3) mechanical properties, 4) bioresorbable medical grade materials, 5) bioactivity, and 6) appropriately scaled production methods compliant with medical …