Polymer Science Commons^™

Glass Transition Temperature Of Plga Nanoparticles And The Application In Drug Delivery, Guangliang Liu

Dissertations

The glass transition temperature (T_g) of poly(D,L-lactic-co-glycolic acid) (PLGA) nanoparticles plays a crucial role in governing molecular mobility, diffusion, and consequently, drug release kinetics. However, the interaction among residual surfactant, drug effect, nanoscale confinement, and release medium on T_g remains insufficiently characterized. This study aims to bridge this gap by correlating the thermal behavior of PLGA nanoparticles with their drug release behavior under physiologically relevant conditions.

In the present study, PLGA nanoparticles were synthesized using both nano-emulsion and surfactant-free nano-precipitation approaches. The influence of residual surfactants - poly(vinyl alcohol) (PVA) and didodecyldimethylammonium bromide (DMAB) - was systematically …

Molybdenum-Doped Zinc Oxide Nanocomposite For Sustainable Photoelectrocatalytic Degradation Of Dyes And Antimicrobial Activity, Samar A. Salim

Nanotechnology Research Centre

Mo-doped ZnO nanocomposite was synthesized by using auto-combustion method. X-ray diffraction patterns of prepared nanocomposite indicated effective construction of crystalline Mo/ZnO NCs with co-existence of MoO2 and ZnO in required weight ratio. XRD results revealed also that ZnO crystallite size decreased as Mo-doping concentration increased. The direct band gap reduced from 3.309 eV of (MZ-0) to 3.258 eV of (MZ-5), demonstrating a negative correlation with Mo-doping levels. The electrocatalytic activity of Mo/ZnO NCs was assessed by their capability to degrade Indigo Carmine (IC) and Murexide (ME) dyes, and their antibacterial properties were also evaluated. The electrocatalytic (EC) degradation efficiencies for …

Strengthening Kidney Dialysis One Membrane At A Time: Enhancing Tempo-Oxidized Nanocellulose And Ionic Liquid Membrane Strength Through The Variation Of Cosolvents, Bailey M. Butler

Chemical Engineering Undergraduate Honors Theses

Chronic kidney disease occurs when the kidneys lose the ability to effectively filter the blood, which causes waste build up. End-stage kidney disease (ESKD) is the most severe case of kidney disease and requires either dialysis or a kidney transplant. Hemodialysis, the most common form of dialysis, is an extremely time-intensive and physically burdensome process that is currently limited by membrane performance. The polysulfone (PSf) membranes that are widely used for dialysis today have many limitations, including fouling, toxin rejection, and essential protein loss. Recently, new membranes made from TEMPO-Oxidized nanocellulose dissolved in 1-ethyl-3-methylimidazolium acetate (EMIM-Ac) have shown promising characteristics, …

Adsorption Of Pfas On Bridged Functionalized Organosilica Materials, Elisha Lawerh Kabutey

Electronic Theses and Dissertations

PFAS are hazardous contaminants that have a devastating impact on human health and the environment. Their hazardous nature has led to the development of various adsorption methods for removing these contaminants from water sources. In this study, functionalized organosilica materials were synthesized from bis[3-(trimethoxysilyl)propyl] amine using the sol-gel method. The surface amino groups of the organosilica were converted into amine hydrochloride groups. Their adsorption properties were evaluated using salts of perfluorooctanoic acid, perfluorooctanesulfonic acid, and perfluorobutanesulfonic acid. Results showed excellent adsorption capacity of the materials. Adsorption of PFAS leads to particle agglomeration and flotation of the spent material. A column …

Polymer Charge Effects On Scaling In Membrane Distillation, Lucia Milans Del Bosch

Chemical Engineering Undergraduate Honors Theses

This research evaluates the effectiveness of polymeric inhibitors at suppressing scaling during direct contact membrane distillation (DCMD). Anionic polyacrylic acid (PAA), neutral polyethylene glycol (PEG), and cationic polyethyleneimine (PEI), were investigated. Experiments were conducted using both hypersaline single-salt and multi-component mixed-salt feeds to determine how the presence of different ions influences performance. Results from single-salt experiments showed that PAA and PEG effectively maintained permeate flux through chelation and steric hindrance, respectively, while PEI caused rapid membrane failure due to interfacial aggregation and pore wetting. In complex mixed-salt solutions, PEG was the additive, maintaining a steady flux with only a 7.33% …

Cationic Polymer-Grafted Magnetic Nanoparticles For Enhanced Removal Of Anionic Dyes From Wastewater, Joia A. Traver

Chemical Engineering Undergraduate Honors Theses

Water scarcity and pollution are escalating global challenges, with textile industry wastewater often enriched with toxic dyes posing significant risks to environmental and human health. These contaminants increase turbidity, reduce dissolved oxygen levels, and ultimately impair aquatic ecosystems. This thesis focuses on the remediation of dye-contaminated water using nanoscale polymeric adsorbents. Methyl orange, a common anionic dye widely used in textile and leather industries, was selected as the model contaminant due to its terminal sulfonate group, which enables strong electrostatic and hydrogen-bonding interactions with cationic functional materials.

In this work, magnetic nanoparticles grafted with cationic polymers were synthesized and evaluated …

Electrochemical And Mechanical Evaluation Of Cellulose Acetate Electrolyte Films As A Function Of Polyetherimide And Polyethylene Glycol Additives For Supercapacitor Applications, Chase E. Golden

Chemical Engineering Undergraduate Honors Theses

Polymer electrolytes for supercapacitor applications require a balance between mechanical robustness and electrochemical performance. In this study, cellulose acetate (CA) films were modified with additives such as polyetherimide (PEI) and polyethylene glycol (PEG) to test how compositional changes influence mechanical performance, ionic conductivity, and electrochemical charge storage. Films were cast using phase inversion, soaked in a 1 M NaCl aqueous solution, and characterized using Fourier-transform infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and tensile testing. Films were also evaluated based on fluid uptake for insight into electrolyte retention.

Characterizations show that the addition of PEI increased ionic …

Bridging Reaction Engineering And Polymers Design: Solvent Effects In Continuous Flow Copolymerization, Leila Ba

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

Poly(glycidyl methacrylate-co-methyl methacrylate) [poly(GMA-co-MMA)] is a promising functional copolymer for photoresist applications due to its reactive epoxy groups and tunable physicochemical properties. This thesis is focused on this polymer and integrates theoretical solubility prediction, thermodynamic modeling, and continuous-flow synthesis to establish quantitative structure–process–property relationships for their use in microelectronic-grade solvents.

Solubility behavior in dimethyl sulfoxide (DMSO), propylene glycol monomethyl ether (PGME), and propylene glycol monomethyl ether acetate (PGMEA) was investigated using the Hildebrand and Hansen models, Hoy group-contribution method, Polymer Genome machine-learning platform, and Flory–Huggins thermodynamic analysis of Gibbs free energy of mixing. Experimental saturation solubility measurements at 25 °C …

Molecular Origins Of Non-Frozen Water In Polyelectrolyte Brushes, Ali Dhinojwala, Saveen Jayaweera, Md Golam Kibria, George Mallinos

University Research

Polyelectrolyte brushes (PEBs) are promising coatings for reducing ice adhesion and regulating water freezing at interfaces, yet direct measurements of nonfrozen water retention at subzero temperatures remain scarce. Here, we investigate the freezing behavior of water confined in poly([2-(methacryloyloxy)ethyl]trimethylammonium) (PMETA) brushes with chloride, iodide, and sulfate counterions using a custom-built low-temperature attenuated total reflectance infrared spectroscopy system. Furthermore, we quantify the fraction of water that was present within the brush that does not freeze as well as the changes in polymer volume fraction within the brush as a function of temperature. Spectroscopic analysis of water vibrational modes reveals that PMETA …

Fly Ash Proppant Developed For Hydraulic Fracturing, Raz Rzgar Haydar

Theses and Dissertations

Proppants are critical components in hydraulic fracturing, used to maintain fracture conductivity and enhance reservoir stimulation. In high-pressure and harsh reservoir environments, the use of high-strength proppants is essential to ensure well performance. Conventional proppants, being sand, ceramic, and sintered bauxite can be expensive, and their use often requires costly fracture fluids. This study investigates the possibility of utalizing fly ash geopolymers as a sustainable alternative that is also cost-effective for proppants manufacturing. Fly ash, a by-product from the combustion of coal and other materials, was explored as a base material for proppants, utilizing an alkaline solution as an activator …

Transient Grating Spectroscopy Nondestructively Characterizes The Mechanics Of Rubbery Polymers And Soft Gels, Christopher W. Barney, Angela A. Pitenis, Bolin Liao, Allison L. Chau

University Research

Designing efficient mechanisms for moving mechanical assemblies requires the use of materials with well-defined mechanical responses. Appropriate methods are needed to characterize these mechanical responses. Mechanical characterization of soft materials is critical in the high strain rate regime where intuition from manipulating a material at low rates fails to translate to applications including impact protection, tire traction, and sound damping. Here, transient grating spectroscopy (TGS) is used to measure wave propagation for soft elastomers and hydrogels. TGS is a non-destructive and non-contact optoacoustic technique that enables high strain rate measurements of the bulk modulus, a measure of a material's resistance …

The Role Of Side-Chain Length And Counterion Mediation On Dimerization Of Rigid Sphere-Rod Amphiphiles: A Molecular Dynamics Investigation, Mesfin Tsige, Tianbo Liu, Javad Tamnanloo, Abdol Hadi Mokarizadeh

University Research

Rigid sphere-rod amphiphiles (RSRAs) comprising a Keggin polyoxometalate (POM) headgroup and an oligofluorene rod with different side chain lengths (C2, C6, C10, C16, are the number of carbon atoms per side chain) were probed by all-atom molecular dynamics in THF/water mixtures (15 and 33 vol % THF) with tetrabutylammonium (TBA+) counterions to elucidate the molecular origins of dimerization. Despite strong Keggin-Keggin electrostatic repulsion, stable dimers form through a synergy of (i) hydrophobic rod/side-chain interaction that strengthens with side-chain length and (ii) counterion-mediated attraction by TBA+, which localizes near the Keggins to screen electrostatic repulsion. Packing evolves from near-parallel rods for …

Convergence Of High Throughput Experimentation And Machine Learning To Rapidly Advance Application-Specific Polymer Development, Mashrafee Aryan, Daniel Struble, Felix Campbell, Saroj Upreti, S. M.Ashik Abedin, Aahil Khambawla, Jeetain Mittal, Michael S. Dimitriyev, Emily B. Pentzer, Svetlana A. Sukhishvili, Xiaodan Gu, Boran Ma

Faculty Publications

Machine learning (ML) has heavily influenced the way scientific study is done with demonstrated successes in nearly every field. However, furthering performance and explainability of ML models in increasingly complex systems and with increasingly demanding outcomes requires a significant influx of high-quality data. To that end, this Review covers some of the techniques, instrumentation, and methodologies that have shown promise for significantly accelerating the discovery of polymer materials, optimization of their properties, and elucidation of property–application relationships through high throughput (HT) experimentation, characterization, and analysis. Attention is given to not only ML, but also to hardware advancements and their synergy …

Made On Mars: Design And Manufacturing Of Structural Polymer-Regolith Composites, Pailey M. Vitale

Williams Honors College, Honors Research Projects

Human exploration of Mars is constrained by harsh environmental conditions and the prohibitive cost of transporting materials from Earth. Long-term sustainability requires the local production of mechanical and structural components using resources available on Mars, thereby minimizing payload mass. This project investigates polymer–regolith composites derived from atmospheric CO₂ and mineral-rich regolith as a pathway toward in-situ manufacturing. These composites, when compatible with additive manufacturing, could replace imported plastics, enable on-demand fabrication, and support closed-loop recycling systems. The objective is to design and evaluate polymer–regolith composites that maintain mechanical integrity and environmental resistance under Martian conditions, including extreme temperature swings, radiation …

Energy Efficient Windows Using Pvme, James S. Bronstrup

Williams Honors College, Honors Research Projects

This Honors Project aims to improve window energy efficiency using the thermoplastic polymer PVME (polyvinyl methyl ether), which displays temperature-dependent transparency that can be adjusted by mixing it with water and salt to reduce heat transfer through a window. The objective is to determine the optimal PVME water-salt ratios for placement inside a windowpane, evaluate energy savings compared to a traditional argon-filled window, and compare estimated costs. A small-scale model will test different concentrations for various climates, with heat transfer measured by temperature indicators via a LabQuest. Building on research by Yang Zhou at Nanyang Technological University, who used a …

Microscopic Insights On Shear Rheology Of Polyampholyte Ionomers Via Molecular Simulations, Kyle Vonscio

Williams Honors College, Honors Research Projects

Ionomers are polymers that contain a small fraction of charged groups. The ionic attraction of charged groups allows ionomers to act similarly to crosslinked polymers. Depending on the strength of electrostatic interactions and structure of the ionomers, different dynamics and rheological responses can be observed. With moderate attraction between ions, these noncovalent crosslinks can be broken when heated, allowing ionomers to flow and show the strength of a crosslinked network at low temperatures. Nonequilibrium molecular dynamics (NEMD) simulations will be performed under shear in the xy-plane and the macroscopic rheology and conformation of the polyampholyte ionomer will be determined. The …

Analyzing The Effect Of Network Properties On Self-Assembly Of Polymer Grafted Nanoparticles In Vitrimer Nanocomposites, Tyler Eakin

Williams Honors College, Honors Research Projects

This project aims to show the how polymer grafted nanoparticles behave in a vitrimer composite network. The effect of varying the network parameters such as the grafting density, the volume fraction of nanoparticles, and the ratio of polymer chain length : graft chain length will be studied. The assemblies formed by the polymer grafted nanoparticles will be visually analyzed and assigned one of 5 possible conformations. A phase diagram of grafting density vs network chain length / graft length will be constructed. The phase diagram will provide valuable insight into how nanoparticle self-assembly can be manipulated through changing network parameters

Effects Of Hofmeister Ions On Lower Critical Solution Temperatures Of Poly(N-Isopropylacrylamide) And Poly(Vinyl Methyl Ether), Joseph Joaquin

Williams Honors College, Honors Research Projects

The goal of this study is to compare how four different Hofmeister anions (Cl-, SCN-, F-, and I-) affect the Lower Critical Solution temperature (LCST) on two thermo-responsive polymers: poly(N-isopropylacrylamide) (pNIPAAM) and poly(vinyl methyl ether) (PVME). pNIPAAm is commonly used in the environmental applications such as monitoring, oil-water separations, or antifouling materials, and in medical industry from drug delivery to tissue engineering. When pNIPAAM or PVME reaches a temperature above their LCST, they become hydrophobic, and the polymer chains coiled, leading to their aqueous solutions turn opaque. PVME exhibits a similar LCST as that of pNIPAAM, so it can be …

Surface Immobilization Of Stimuli-Responsive Polymers Using A Network Of Aminopropyltriethoxysilane, Walter Bungard, Ryan Nixon

Williams Honors College, Honors Research Projects

The goal of this honors project is to develop a cost-effective and accessible method for entrapping stimuli-responsive polymers onto solid substrates using aminopropyltriethoxysilane (APTES). The entrapment network process will first be replicated on glass or silicon using APTES and poly(N-isopropylacrylamide), involving spin coating and thermal annealing to chemically bond the polymer to the substrate. Once validated, the method will be applied to other stimuli-responsive polymers, including thermo-responsive, electroactive, and pH-sensitive types, with APTES as a control. For each sample, film stability, responsiveness, and surface behavior will be evaluated using contact angles, optical microscopy, and spectroscopic analysis, followed by statistical evaluation. …

Bio-Papcz: Corn Starch-Based Composite Bioplastic Reinforced With Pineapple Leaf Fiber (Palf), Zinc Oxide (Zno), And Polyvinyl Alcohol (Pva), Marvin C. Caya, Shervin Austin C. Huang, Jovar Khalel J. Maghari, Ruel M. Levida

Sinaya: A Philippine Journal for Senior High School Teachers and Students

Plastic pollution poses a serious global threat, as petroleum-based plastics persist for centuries, and their surging production of over 450 million tons overwhelms ecosystems (Ritchie et al., 2023). Using a quantitative experimental research design, the study examined the effects of varying concentrations of cornstarch-based bioplastic reinforced with pineapple leaf fiber (PALF), polyvinyl alcohol (PVA), and zinc oxide (ZnO) on the bioplastic’s tensile strength and soil degradability. Sample C2 (ZnO 3.0 %w/w; PVA 9.0 %w/w) demonstrated the optimal tensile properties with a tensile strength of 0.76 MPa and an elongation at break of 6.40%, which was attributed to the addition of …

Purifying Circular Rna Therapeutics, Karen Guillen-Cuevas

All Dissertations

Circular RNA (circRNA) has emerged as a promising therapeutic modality due to its enhanced stability and resistance to exonuclease degradation compared with linear mRNA. However, its stability and functionality depend strongly on achieving high purity, and current methods such as size-exclusion chromatography suffer from peak overlap, low yields, and poor scalability. This dissertation addresses these limitations by developing ultrafiltration-based strategies to purify circRNA directly from in vitro transcription (IVT) and self-splicing (circularization) reactions. First, the feasibility of ultrafiltration was demonstrated using polyethersulfone membranes, where sieving coefficients and critical flux values of circRNA, precursor RNA, and nicked RNA were measured to …

The Science And Economics Of 3d-Printed Filament Recycling, Michael Domingo, Dane Freund, John Mcswiggin, Adam Meadows

Sustainability Conference

In recent years, 3D printing has grown rapidly, both in homes and commercially. This has led to increased demand for plastic filaments, many of which contribute to plastic waste. This project explores the potential of recycling household plastics into 3D printing filament, promoting sustainability and creating a circular economy. Materials like PLA, PETG, ABS, and polypropylene can be recycled or even composted. Existing research has shown that recycled filaments can maintain comparable tensile strength to their virgin counterparts, depending on the recycling process. Furthermore, implementing circular economy practices for plastics could save billions annually by mitigating pollution and reducing landfill …

Effect Of Varying Chitosan Molecular Weights On The Morphology And Physical Characteristics Of Pva/Chitosan Composite Hydrogels, Yuan Alfinsyah Sihombing, Halida Rahmi Luthfianti, William Xaveriano Waresindo, Marathur Rodhiyah, Nur’Aini Nafisah, Dian Ahmad Hapidin, Dhewa Edikresnha, Khairurrijal Khairurrijal

Makara Journal of Science

We employed the innovative freeze–thaw method to investigate the effect of chitosan (CS) molecular weights incorporated into polyvinyl alcohol on the morphology and physical characteristics of the hydrogel. This study aimed to unravel the intricate relationships between CS molecular weight variations, CS concentration, and the number of freeze–thaw cycles (4 or 6 cycles) on hydrogel swelling degree and weight loss. Incorporating CS improved the hydrogel structure and enhanced its porosity, resulting in remarkable increases in swelling degree ranging from 2 to 6 times the initial weight. Higher molecular weight CS (310,000–375,000 Da) exhibited a lower swelling degree than medium molecular …

Superhydrophobic Cerium-Based Metal–Organic Frameworks/Polymer Nanofibers For Water Treatment, Samar A. Salim, Hani Nasser Abdelhamid,

Nanotechnology Research Centre

No abstract provided.

Polymer-Enhanced Nanopore Sensing, Eugene Gyasi Agyemang

Graduate Theses and Dissertations

The resistive pulse technique characterizes single analytes by detecting fluctuations in the ion current as they pass through a narrow orifice connecting two electrolyte-filled chambers, each containing a single electrode. The amplitude, shape, frequency, and duration of these fluctuations primarily provide information about the analyte’s size, shape, concentration, and net surface charge, respectively. One configuration for resistive pulse measurements is of an electrolyte-filled nanopipette immersed in a bath, where the nanopipette tip acts as the nanoscale orifice. It was previously shown that incorporating the large quantities polymer polyethylene glycol (PEG 8K, 50% w/v) into the external electrolyte bath dramatically enhanced …

Theoretical And Experimental Investigation Of Liquid-Liquid Phase Separation: Characterizing Elastin-Like-Polypeptides, Adam D. Quintana

Chemical and Biological Engineering ETDs

This dissertation develops and validates a semi-empirical Flory–Huggins-based interaction model, combined with Cahn–Hilliard simulations, for predicting multi-component liquid–liquid phase separation (LLPS) in elastin-like polypeptide (ELP) systems. Equilibrium droplet compositions, measured using a PDMS-based microfluidic device, enabled direct parameterization of interaction coefficients. The model was applied to generate phase diagrams and assess composition dependence in ternary mixtures. Cahn–Hilliard simulations were conducted to explore potential phase morphologies under different interfacial conditions. Multi-component Lattice Boltzmann simulations were implemented to model droplet morphology evolution under varying interfacial and diffusive parameters, reproducing experimentally relevant morphologies. A three-phase wetting study revealed conditions for selective wetting and …

Experimentally Driven Numerical Model Of Carbon/Polyaniline-Based Glucose Monitoring Sensors: An Evaluation Using A New Figure Of Merit, Ziad Khalifa, Kyrillos Selim, Amira Ali, Sameh Abdellatif

Chemical Engineering

This study presents an experimentally driven numerical model for evaluating carbon/polyaniline (PANI)- based glucose monitoring sensors (GMSs), focusing on innovative configurations using graphene-PANI and carbon nanotube (CNT)-PANI composites. We performed a thorough analysis of the morphological, electrophysical, and electrical properties of these materials, ultimately leading to the extraction of key electrical parameters for integration into a finite element model (FEM). This model simulates the entire sensor, enabling the estimation of critical performance metrics such as sensitivity, limit of detection (LOD), linearity, and power consumption. Our findings demonstrate that the CNT-PANI configuration significantly outperforms the laser-induced graphene (LIG)-PANI electrode, achieving a …

Removal Of Fluoroquinolones From Water Systems Employing Rice Husk Composited Sponges Via Nanoadsorption, Dalia Kanaa

Theses and Dissertations

A novel nanocomposite of polyvinyl alcohol formaldehyde (PVF) sponge loaded with green zinc oxide nanoparticles (ZnONP) and referred to as (NP-PVF) was fabricated as a potential adsorbent of ciprofloxacin from water. A simple mechanical foaming process was used to synthesize the adsorbent. Rice husk extract was used to synthesize zinc oxide nanoparticles (ZnONP) for its phytochemicals as reducing agents. A facile and low-energy-dependent extraction method was used that did not require the use of high-temperature annealing. The synthesized nanoparticles showed a maximum UV absorption at 347 nm, which corresponds to a 3.58 eV band gap energy. FTIR confirmed the successful …

Chemical Recycling Of Pet Plastic Waste, Charlie Parker, Benjamin Puga, Jake Verschoor

Materials Engineering

The growing accumulation of plastic waste, specifically polyethylene terephthalate (PET), has driven the need for more efficient and scalable chemical recycling methods. This study investigated the methanolysis of PET using zinc oxide (ZnO) nanoparticles as a catalyst and tetrabutylammonium chloride (NBu₄Cl) as an ionic liquid, aiming to reduce methanol consumption while achieving high PET conversion efficiency. ZnO nanoparticles were synthesized via wet chemistry and characterized using Dynamic Light Scattering (DLS), which showed an average particle size of 13.5 nm with a polydispersity index of 0.1556, indicating a moderately-high monodisperse distribution of particles sufficient for reactions. The main conversion product, dimethyl …

Effect Of Household Oil Contamination And Agricultural Soil Contamination On Phyllosilicate Nanocatalyst Performance During Pyrolysis Of Polyolefins, Joey Velasquez

Master's Theses

The effect of household oil and agricultural soil contamination on catalyst performance during polyolefin pyrolysis was simulated on mixed virgin plastic pellets by evaluating contamination influence on mixed plastic degradation temperatures. Three phyllosilicate nanocatalysts including Fulcat435, Fulcat22F and Y-Zeolite were evaluated in this work based on a literature review of catalyzed plastic pyrolysis and these catalysts’ ability to lower plastic decomposition temperature by 50 °C – 100 °C. These findings were confirmed in this research through thermogravimetric analysis of a polyolefin mixture and further developed in furnace experiments containing household oil and agricultural contamination. Household oil contamination deactivated each of …