Polymer Science Commons^™

Research On 3d Printing Resin Exposure Properties And Its Application On Centrifugal Microfluidic Platform Based On Fluorescence Detection, Zheng Qiao

LSU Doctoral Dissertations

This dissertation encapsulates significant advancements in the field of SLA 3D printing and centrifugal microfluidics. Central to the research is the development of a novel mathematical model for predicting trapped resin thickness in SLA 3D printing, a groundbreaking contribution that addresses a critical aspect of printing intricate structures. This model, the first to establish a mathematical relationship for resin thickness, is rooted in a comprehensive study of the resin curing process. The research leverages the concept of 'critical dosage' for resin curing, leading to a more refined and theoretically grounded approach for calculating curing thickness. Experimentation further validates the model, …

Thermal Frontal Polymerization – Applications In Coatings And Composites, Maria Martinez

LSU Doctoral Dissertations

Thermal frontal polymerization has long been used as a method to cure composites and coatings. However, this is the first time these applications have been used without the use of a catalyst, for the case of composites and coatings.

Chapter 2 discusses how to optimize cure-on-demand, thin layer coatings, using frontal polymerization. Previously, for the use of curing thin layer coating using thermal FP, it was known to just make the formulation viscous enough, as this would prevent premature quenching caused by heat loss. It was discovered that for a given layer thickness, a minimum viscosity and initiator concentration were …

Quasi-Static And Impact Load Response Of Bfrp-Reinforced Concrete Beams And Post-Terrorist-Attack Sub-Assemblages, José Luis Carrasquillo

Civil & Environmental Engineering Theses & Dissertations

This dissertation presents the outcome of a theoretical and experimental study of Basalt Fiber Reinforced Polymer (BFRP) reinforced concrete beams and post-terrorist-attack subassemblages subjected to either quasi-static or impact load. Both BFRP reinforcement as well as BFRP fabric are used in this investigation. The sub-assemblage consists of an otherwise two-span beam converted to a fixed-end single-span one owing to the loss of a middle column blasted off during the terrorist attack. The simply supported beams are subjected to a midspan quasistatic or an impact load. However, each sub-assemblage is subjected to a quasi-static load up to collapse to simulate the …

Engineering Nanofibers: Laboratory Characterization, Microstructural Analysis, And Image Processing Insights, Sayed Ahmadreza Razian, Mohammad Arjomandi, Kaspars Maleckis

UNO Student Research and Creative Activity Fair

Polymer nanofibers have attracted high interest in a wide array of applications, including biomaterial scaffolding, textiles, sensors, reinforcement in composites, and filtration systems. Many of these applications combine nanofibers into non-woven fabrics for better properties and easier manipulation. The properties and performance of nanofiber-based fabrics are affected by various microstructure parameters, including fiber alignment, diameter, and gap sizes between the nanofibers. These structural parameters can be controlled by adjusting various process parameters during manufacturing process, but the exact process parameter-microstructure relationships vary depending on the polymer system and need to be studied individually. The goal of this study is to …

Radiation-Induced Polymerization Of Thermo-Responsive Polymers And Comprehensive Characterization For Improved Performance, Attia Attia, Islam Mohamed Eng., Mohamed El-Deab Prof., Nabila Maziad Prof.

Petroleum Engineering and Gas

Early water breakthrough with high water cut through highly conductive thief zones is a prevalent problem in many water-flooded oil reservoirs. Smart polymers that are sensitive to temperature changes, also known as thermo-responsive polymers, e.g., polyethylene glycol (PEG) have great advantages over conventional polymers that can be exploited to solve the problem of conductive thief zones. Thus, this study aims at designing and synthesizing a thermo-responsive polymer using Gamma Ray Induced radiation with good tolerance against high temperature, and high salinity reservoir conditions with feasible and economic synthesis procedure for application in Egyptian oil reservoirs. That is a combined use …

Synthesis, Characterization, And Performance Assessment Of Reusable And Biodegradable Antimicrobial Polymeric Membranes For Aerosolized Pathogen Inactivation And Filtration, Ebuka Ogbuoji

Theses and Dissertations--Chemical and Materials Engineering

Air filtration technology has proven effective in purifying air by trapping particulates which can cause adverse health effects. High Efficiency Particulate Air (HEPA) filters, capable of capturing over 99.99% of PM_0.3, are recommended for critical applications. However, conventional non-woven HEPA filters rely on electrostatic interactions to trap smaller particles, which can deplete over time or after cleaning, reducing filtration efficiency and posing health risks. Additionally, these filters contribute to plastic waste.

This dissertation investigated the feasibility of using flat sheet polymeric membranes fabricated via nonsolvent-induced phase separation (NIPS) as reusable and biodegradable alternatives to commercially available non-biodegradable air …

Dough Rheology And Its Influence On Sheeting Behavior, Najat Albarakati

Graduate Theses, Dissertations, and Problem Reports (ETD)

Dough is the starting material for a large number of baked products, including cookies, crackers and bread. In commercial food processing operations, it is desired to obtain the same product and with the same dimensions in a reproducible manner in order to minimize waste. In the case of dough, the flour used, and the nature and amount of ingredients employed depend on the specific product and the market served. This research was aimed at relating cracker dough rheology to sheeting behavior between two counter-rotating rollers. The sheet that is formed is used to punch out the crackers that are then …

Experimental Evaluation Of Mesh Size In Physically Crosslinked Polymer Gels Using Dynamic Light Scattering, Duncan M. Hill

Honors Theses

Block copolymer gels are under consideration as drug delivery patches. Controlling and modeling the transport inside the gel is an important contribution to the successful delivery of pharmaceuticals. The diffusive transport of a solute – such as a therapeutic compound – within the gel can be described by the mesh size of the gel, which is defined as the distance between polymer chains. Existing experimental evaluations of mesh size do not work for block copolymer gels due to differences in the fundamental gel structure. As such, an experimental method of measuring mesh size of block copolymer gels using dynamic light …

Optimized Pi Compound Mixing Strategy, Cecilia Mainzer

Williams Honors College, Honors Research Projects

The project focuses on developing an optimal mixing strategy for a polyisoprene (PI) compound at the Goodyear Tire & Rubber Company. The aim is to optimize performance objectives of the compound. The project involved research, design iterations, mixing analyses, and performance evaluations, while adhering to engineering codes and standards.

The design process includes analyzing differences between two mixing technologies, intermesh and tangential rotors; altering mixing conditions; and exploring additional polymer systems and coupling technology of the compound.

Validation data confirms that the mixing technology and compound recipe meets all success metrics, including stiffness, hysteresis, adhesion, cure rate, and tear performance …

The Effects Of Relative Humidity And Valency On Water Absorption And Structure In Polyelectrolyte Brushes, Andrea Klima

Williams Honors College, Honors Research Projects

The purpose of this project was to understand the relationship between relative humidity, ion valency, and the structure of water on positively (PMETAC) and negatively (PSPMA) charged polyelectrolyte brushes. The polyelectrolyte brushes were synthesized using Activators Regenerated by Electron Transfer Atom Transfer Radical Polymerization (ARGET ATRP) and were soaked in concentrations containing 0.1 M of the target counterion. The brushes were then exposed to humid vapor, and spectra were collected in 5% intervals between 0% and 85% for each counterion. Two trials were completed for each counterion studied to ensure agreement between datasets. In all spectra, peaks appeared for the …

Schaeffler Icvd Coating Machine, Louis Mcgrath

Williams Honors College, Honors Research Projects

Chemical Vapor Deposition (CVD) is mutual technology used to deposit thin film through a gaseous phase by vaporizing the solid materials. This conventional process usually requires high thermal stability of the materials, which is not applicable for most of the polymeric materials. Therefore, a novel process, initiated Chemical Vapor Deposition (iCVD) is developed by introducing the gaseous monument and initiator to form the thin film in-situ. By adjusting the free-radical polymerization in the vapor phase, a variety of thin and uniform polymer films can be achieved. Depending on the chemistry, iCVD has many categories. This report explains the design …

Degradable Staples And Delivery Device, Meha Elango, Jessica Cabrera, Makayla Scarpitti, Kareemat Melaiye

Williams Honors College, Honors Research Projects

The scope of this project is to design a method to secure skin grafts to healthy tissue. The ultimate goal for the proposed method is to be dissolvable in some form. Currently, skin grafts procedures utilize staples in most cases to hold a skin graft in place, but there are disadvantages that come with it. Staples are easy to place, but time consuming during the removal procedure. They also cause a lot of pain and discomfort for the patient. The goal of this project is to determine a way a secure skin grafts to healthy skin in order to reduce …

Construction Composites Of Recycled Pvc And Recycled Polyolefins, Natalie Prusovic

Williams Honors College, Honors Research Projects

Current construction composites are typically only composed of polyvinyl chloride (PVC) and recycled PVC (rPVC). This proposed project will investigate if recycled polyethylene (rPE) and polypropylene (rPP) can be used instead of PVC in those materials. Different compositions of rPE, rPP, and rPVC blends will be compounded and a T-peel test will be performed to test the adhesion.

Exploring Natural Raw Materials For The Development Of Hot Melt Adhesives For Linings Of Paintings, Erica Factor

Williams Honors College, Honors Research Projects

Natural raw materials will be explored for developing hot melt adhesives for the lining of paintings. The leading raw material is a natural resin called "Damar". This resin is obtained from the tree family Dipterocaupocea in India and Southeast Asia. This material has shown promising results from initial testing. Damar, with the potential for other natural raw materials, will be combined with synthetic ingredients to create sustainable formulations. The formulations will be tested on linen to replicate the application onto paintings. The sustainability, tackiness, texture, and overall performance of each formula will be considered. Once a formulation has been selected, …

Removal Of Residual Stress In 3d Printed Polymers, Christian Jenkins

Williams Honors College, Honors Research Projects

This project aims to investigate the relationship between stress relaxation and the reduction of dimensional shrinkage and warping in 3D printed polymers produced through fused filament fabrication. The hypothesis suggests that residual stress in 3D printed structures results from factors such as temperature differences, molecular-level contributions, and rapid cooling, causing post-printing warpage and damage. To mitigate these issues, the project proposes annealing 3D printed polymers in a hot sandbath to allow stress relaxation without warping. The study will employ a Dynamic Mechanical Analysis (DMA) machine to assess mechanical properties of relaxed and unrelaxed samples, comparing their effectiveness. The project's timeline …

Functionalized Microfiltration Membranes For Aerosol Capture To Chloro-Organic Degradation, Rollie George Mills

Theses and Dissertations--Chemical and Materials Engineering

The environmental remediation of water and air sources is a challenging field, due to widespread contamination, pollutant variety, and efficiency of existing treatment options. Remediation of certain pollutants, such as per- and polyfluorinated chemicals (PFAS), polychlorinated biphenyls (PCBs), volatile organic compounds (VOCs), and viral aerosols, has shown promise via adsorptive, degradative, or filtration-based processes, each with their respective advantages and limitations. Membrane technology is one option that has exhibited considerable pollutant removal from environmental sources via reverse osmosis (RO) filtration, but is limited by low permeabilities and lack of pollutant detoxification. With the support of NIEHS and NSF, the functionalization …

Development Of Glutathione-Responsive Disulfide-Containing Poly(Beta-Amino Esters) With Varied Hydrophilicity And Acrylate Functionality, Anastasiia Aronova

Theses and Dissertations--Chemical and Materials Engineering

Smart biomaterials are becoming promising for therapeutic deliveries due to their ability to respond to changes in the environment. Redox-responsive hydrogels are a promising type of smart polymer that can swell and degrade according to cellular oxidative stress levels. Glutathione, abundant in cells, is crucial in redox-responsive biomaterials, serving as a key reactive molecule. This study explored the degradation kinetics of glutathione-responsive poly(β-amino ester) (PBAE) polymers created through a single-step Michael addition. We examined how disulfide content influences the degradation kinetics of these PBAE networks. Additionally, we investigated how the hydrophilicity and functionality of acrylate affect the degradation of disulfide-containing …

Sustained Release Systems For Endometrial Cancer, Claire E. Rowlands

Theses and Dissertations--Chemical and Materials Engineering

Endometrial cancer (EC) is the sixth most common cancer in women worldwide and is the most common cancer of female reproductive organs. From 2007-2016 there has been a global rise in incidence of EC of 1.3 %. Typically, EC is treated with surgery, but at later stages surgery is less effective requiring chemotherapy and/or radiation therapy. These treatment options are less effective than surgery and there are very few FDA approved chemotherapies for EC. The minuscule number of effective treatment options as well as an increase in incidence shows the need for creating improved treatments for EC. There has been …

Novel Membrane Materials For Nutrient Recovery From Nutrient-Rich Resources, Km Prottoy Shariar Piash

Graduate Theses, Dissertations, and Problem Reports (ETD)

Global demand for fertilizer production is expanding substantially to meet the food demand of an increasing world population. Anaerobic digestate (AD) of various centralized wastewater facilities contains substantial amounts of ammonium (NH₄⁺) (300-800 mg/L), potassium (K⁺) (13-120 mg/L), and phosphorus (P) (30-100 mg/L)- based nutrients. In addition to reducing energy costs and CO₂ emissions compared to conventional fertilizing raw material manufacturing, recovering nutrients from these waste streams could help mitigate problems such as eutrophication, which otherwise incurs billions of dollars losses to US economy annually. Apart from nutrients, wastewater streams also contain organic pollutants …

Polylactic Acid (Pla) Containing Talc Microparticles And Amorphous Polyhydroxyalkanoates (Aphas) For Improved Barrier And Mechanical Properties In Food Packaging, Mohammed Alfaifi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Polylactic acid (PLA) is a biobased and compostable polymer that is increasingly being used as an alternative to petroleum-based, non-biodegradable polymers for single-use food packaging due to its environmental benefits. It is also commercially available in large quantities, and it can be processed like polyethylene. However, it has a higher water-vapor permeability (WVP) as compared to polyolefins and polyethylene terephthalate that are the incumbent materials. This results in a competitive disadvantage in employing PLA for packaging baked goods since the shelf life of the food is likely to be reduced. In the past, barrier properties of PLA were improved by …