Engineering Commons^™

Materials Testing For Large Format 3d Printing, William Jenkins

Williams Honors College, Honors Research Projects

An ABS Carbon Fiber blend was printed into single walled hexagons at a variety of settings on a Cincinnati BAAM large format 3D printer. These hexagons were then cut down into sheets and had tensile and flexural test samples cut out of them, in order for materials testing to be performed. Tensile strength, tensile strain, young’s modulus, flexural strength, deflection and elastic modulus were all determined. A desktop CNC machine and a planer were purchased for the manufacturing of these samples, and an efficient cutting procedure was designed and optimized. After all data collection concluded, this data was thoroughly analyzed, …

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 …

Short Strand Carbon Fiber Reinforced Polylactic Acid Filament For Additive Manufacturing, Dale Chenoweth, Lukas Seggi, Luke Phillips

Williams Honors College, Honors Research Projects

In this design project, the additive manufacturing filament of short strand carbon fiber (SSCF) reinforced polylactic acid (PLA) composite was developed. The micro-size, precision cut SSCFs were mixed with the PLA pellets through a melting homogenization process. Through this process the composite material block is cut and divided into pieces for ease of pelletizing. The material block pieces are then pelletized to be fed through the single screw extruder to develop the SSCF-PLA composite filament. The SSCF-PLA filaments were manufactured with a varying amount of SSCF ranging from 0.5% to 10% of the material block's weight. Development of a 1% …

Robot-Based 3d Printing, Aaron Hoffman

Williams Honors College, Honors Research Projects

Details of a large-format 3D printer created to print experimental materials, test multi-axis print techniques, and quickly print large objects. The printer consists of a 7-axis robotic arm and pellet extruder, which are controlled by a PC. Experimental materials such as recycled polymers or carbon-fiber reinforced materials can be easily tested with the pellet format of the extruder. The printer can perform different printing techniques and can be used to experiment with material properties when using these techniques with different polymers. The print surface is around 5 times larger than the average commercial 3D printer, and the robotic arm provides …

Defining The Proper Operating Time For The Septa Extractor, Abigail Jones

Williams Honors College, Honors Research Projects

Anionic polymerizations are a common type of reaction used to produce synthetic rubber. During these reactions, it is necessary to charge initiators, modifiers, and other substances, through pressurized containers that are sealed with rubber septa. These septa prevent oxygen and moisture from entering the pressurized container, and the reactor, though they need to be cleaned before use to remove other impurities. Currently a glass Soxhlet Extractor is used to remove such impurities, and though effective, it has a limited capacity, so it has to run frequently. This limitation led to the commissioning of the Septa Extractor, which is an automated …

Anti-Freeze Double Network Hydrogels, William Gross

Williams Honors College, Honors Research Projects

Three polyethylene glycol (PEG) based crosslinkers with repeat unit nominal weights of 62.1, 200, and 400 g/mol in agar/PAM double network (DN) hydrogels were used to study the effect of different crosslinkers on thermal and mechanical properties. Using the one-pot synthesis method, hydrogels with the PEG crosslinkers or methylene-bis-acrylamide (MBAA) were made via sol-gel transition for formation of agar network, and photopolymerization of the PAM network using Irgacure 2959 as photo initiator. Tensile and compression tests were performed on as prepared, swollen, and swollen & cooled specimens of each hydrogel. Freezing time and thermal imaging were performed in -20 °C …

Comparing Weathering Effects Of Ultraviolet And Xenon Arc Accelerated Aging On Polyvinyl Chloride, Collin Mcinnes

Williams Honors College, Honors Research Projects

As the ubiquitousness of polymers increases and begins seeing use in outdoor settings, the need to fully understand how these materials degrade is also necessary. This study aims to compare two known accelerated aging methods, namely an ultraviolet light chamber and a xenon arc light chamber, to understand what differences, if any, manifest in the mechanical, chemical, and cosmetic deterioration of polyvinyl chloride (PVC) after long-term exposure. The study utilizes Fourier-transform infrared spectroscopy, dynamic mechanical analysis, thermogravimetric analysis, and colorimetry analysis to determine the extent of degradation and potential discrepancies between the aging methods.

Structural Design And Application Of Polymeric Silicon Elastomers, Jacob Wyant

Williams Honors College, Honors Research Projects

The purpose of this project was to determine how the polymeric structure and mechanical properties of this elastomer are affected by the ratio between the polydimethylsiloxane macromolecular chains and the crosslinkers. These were determined via tensile and compression testing. Then, spiropyran was added to observe how this fluorescence and crosslinking agent affected the elastomer. Also, the elastomer’s fluorescent and icephobic nature were tested. The elastomers with a higher ratio of crosslinker to macromolecular chain could withstand higher tensile and compressive strains but failed at lower stresses than their counterparts with lower concentrations of crosslinkers. The elastomers were also found to …

Beeswax Wraps As An Alternative To Single-Use Plastics, Sarah Skiver

Williams Honors College, Honors Research Projects

The project goal was to compare the food storage efficacy of sustainable beeswax wraps verses the single-use plastic methods of resealable plastic sandwich bags and plastic cling wrap. The goal was also to test the reusability of the beeswax wraps, as it is a key advantage of beeswax wraps that is advertised. The project purpose was to explore sustainable and eco-friendly alternatives to single use plastics, which are harmful to the environment in both their production and their disposal. Food spoilage was compared in beeswax wrap, plastic sandwich bags, and plastic cling wrap, and spoilage was also observed in a …

Amino-Polymer For Co2 Capture By Vacuum Swing Adsorption, Sean Billy

Williams Honors College, Honors Research Projects

The applications of sorbent compounds in conjunction with amines and other additives is an innovative method at combating CO2 pollution. An ideal solution would use an amine sorbent to trap the high levels of absorbed CO2 with a low binding energy (less than 45 kJ/mol) and subsequently release them into a stored vessel at ambient temperature with a vacuum swing adsorption system. Attempts at finding a best mixture will be conducted through the usage of a vacuum swing system, utilizing a bed syringe containing the sorbent mix and a vacuum syringe to pull on and subsequently release the CO2 into …

Additive Manufacturing Waste Management System - Plastic Extrusion Process, Gabriel Bennett, Lindsay Liebrecht, David Lyogky, Wilson Woods

Williams Honors College, Honors Research Projects

3D printing is a fast-growing market with its main source of waste being PLA and ABS plastics. In 2019, the global additive manufacturing market grew to over $10.4 billion, crossing the pivotal double-digit billion threshold for the first time in its nearly 40-year history. (SmarTech Analysis, 2020 Additive Manufacturing Market Outlook and Summary of Opportunities Report). The waste is generated from failed prints and rejected support structures which are common occurrences for personal use. Plastic recycling has become one of the leading discussions of environmental protection and waste management. The 3D market currently does not offer an effective and affordable …

Evaluating The Thermoresponsive Properties Of Hydroxypropyl Cellulose Solutions For Smart Window Applications, Adam Reed

Williams Honors College, Honors Research Projects

With HVAC and building energy usage expected to increase, there is a strong need for autonomous thermal management solutions. In particular, there has been a growing interest in thermoresponsive (TR) smart windows that are activated by ambient temperature changes. Most TR smart windows contain a liquid solution between two panes. The goal of this research project was to develop a self-supporting smart window by forming a gel that maintained its TR properties. A gel is less prone to spilling in the case of window breakage. It was also desired to tune the phase transition to occur at environmentally relevant conditions …

Investigation Of Surface Charge Using Faraday Bucket Measurements: Analysis On Electrospun Polyvinylidene Fluoride Fiber Mats, Ryan Kantenwein

Williams Honors College, Honors Research Projects

Piezoelectric polymer materials such as polyvinylidene fluoride exhibit beneficial properties for use in personal protective equipment (PPE) against viral contaminants and other foreign microparticles. The electrospinning process of this material allows for surface charge to develop over a controlled surface area. Kynar 761 at 10 wt% demonstrates increased surface charge after withstanding a flow of aerated NaCl particles from a TSI 8130 instrument. Utilizing voltage measurements from a Faraday bucket, 18 wt% Kynar 761 and MG-15 exhibit surface charge when undergoing an electrospinning process; however, Kynar MG-15 displays lower charge values than that of Kynar 761. Several critical factors such …

A Foundational Approach To Extrusion And Compounding, David Frankart

Williams Honors College, Honors Research Projects

With a history of nearly 200 years, polymer processing and compounding is constantly changing to fit the material science needs of the era. Exposure of undergraduate students to the technology and practices used in industry today in a lab setting would create new opportunities for experiential learning and growth. The objective was to set up a 0.75”, 25 L/D Thermo Haake single screw extruder for lab use and run trials of material in a single screw extruder to set up a basis for experiments. Trials were run of co-polyester resin through a single screw extruder with carbon fiber additives varying …

Impact Of Chain Architecture On The Thickness Dependence Of Physical Aging Rate Of Thin Polystyrene Films, Gregory Brown, Elizabeth Lewis, Bryan D. Vogt

Williams Honors College, Honors Research Projects

The dynamics of polymer thin films have been demonstrated to be significantly altered from the bulk, but the origins of such differences are not well defined. In this work, we seek to understand the differences in the structural dynamics (or physical aging) of polystyrene (PS) through branching and other well defined architectures (comb and centipede). The aging dynamics of ultrathin films (< 30 nm) differ from relatively thick films (100-150nm) with linear PS thin films aging more rapidly than the relatively “bulk-like” thick films. Ellipsometric measurements are used to characterize the physical aging rate of the films. The change in film thickness and refractive index as the films are held below the glass transition temperature (T_g) provides a simple measure of the physical aging. In this study, four different architectures (linear, comb, 4 arm star, and centipede) will be investigated. For each PS architecture, the aging rate will be determined for film …

Solvent-Free Coating Using Maco Bio-Based Reactive Diluent, Ryder James

Williams Honors College, Honors Research Projects

The project performed utilizes methacrylated cardanol (MACO) and a linseed oil resin to test how different weight percentages of MACO affect coating performance. MACO is synthesized from a phenolic lipid extracted from cashew nut shells, which are a cashew industry waste product. Not only does it utilize a waste product, but being a bio-based reactive diluent means it can replace the use of volatile organic solvents that are harmful to both humans and the environment. Weight percentage samples of 0%, 10%, 20%, 30%, and 40% were used. Coatings were applied using a 6-mil drawn down bar, with samples being prepared …

Requalification Of Coated Fabrics Using Chemlok 2332 In Place Of Chemlok 233, Daniel Madler

Williams Honors College, Honors Research Projects

Rubber coated fabrics are an essential component in the deicing systems of the aerospace industry. Adhesives cements are applied to a fabric prior to being pressed into a rubber compound that will adhere to the fabric. The resulting fabric maintains the strength of the fabric with the added benefits of elasticity and compatibility from the rubber compound. UTC Aerospace Systems relies on these coated fabrics to create safe deicers for the aerospace industry. Chemlok 233, a now obsolete primer cement, was used extensively in the coated fabrics used by UTC. Materials testing and performance evaluation allowed for a replacement cement, …

Compression Set Improvement Of Thermoplastic Vulcanizates For High Temperature Tubing, Mitchell Valaitis

Williams Honors College, Honors Research Projects

It was hypothesized that increasing the curative level of the fluorocarbon rubber (FKM) used in manufacturing of thermoplastic vulcanizate (TPV) materials would decrease the compression set values of the TPV enough for it to be suitable as a flexible, lightweight alternative to high operating temperature thermoset rubber tubing currently being used for power steering hose. First, promising TPV formulations were identified by varying the polyamide (PA) and FKM used in a Brabender mixer. Four different types of polyamide and four different types of FKM were investigated, with two of the FKM types and one polyamide type identified as being promising. …

Effects Of Micro-Features On Cell Detachment From Poly(N-Isopropylacrylamide) Coated Polydimethylsiloxane Membranes, Luke Webel

Williams Honors College, Honors Research Projects

The tested hypothesis was that features on polydimethylsiloxane (PDMS) surfaces coated with a poly(N-isopropylacrylamide)/aminopropyltriethoxysilane or pNIPAAM/APTES thin film would accelerate cell detachment than the film coated on a unfeatured surface. This project tested samples with features generated by molds, wrinkling, and sandpaper roughened substrates. Surface feature generation methods were limited to mechanical means, and characterized by microscopy and strain rates. 50/50 mixtures of 1.5 wt.% pNIPAAM/ APTES were used to coat thin films (30-40 nm) on PDMS membranes by spin-coating, and the coated membranes were thermally annealed to chemically graft pNIPAAm/APTES on the membrane and their thermo-responsive property was assessed …

The Influence Of Organic Pigments On Coating Properties, Sarah Medeiros

Williams Honors College, Honors Research Projects

Abstract

The purpose of this project was to identify the qualities of two synthesized organic pigments added to a coating. These high-performance pigments were benzodipyrrolidone and benzodifuranone, which are π-conjugated monomers. These pigments were each formulated into two different pigment concentrations and compared with a control that had no pigment. This project is limited by time constraints and the number of variables that can be tested in that time. Performance testing was conducted to evaluate the qualities of these coatings. The results demonstrated that the coatings were reproducible and most tests had results that were equal to or exceeded the …

Design Of Natural Rubber Extraction From Tks Dandelion, Jehad S. Alrawajfeh, Trevor Cody, Jason Pogozelski

Williams Honors College, Honors Research Projects

A design was developed for a controlled environment agriculture 3D greenhouse to grow and harvest TKS dandelions, as well as a processing plant to extract natural rubber and inulin from the roots. The design capacity was scaled for both pilot- and full-scale production: 100 and 100,000 tonnes of natural rubber per year, respectively. The byproducts of the process were dandelion greens, inulin, cellulose, and glucose; all of these except for cellulose were able to be valorized. The greenhouse was designed based on existing 3D hydroponic growing environments, and the extraction process was designed based on the original TKS dandelion extraction …

Rubber Additives To Concrete Specimens, Kendall J. Sweitzer, Mary Mccannon

Williams Honors College, Honors Research Projects

Rubber, as an additive to concrete, would hypothetically cause a concrete specimen to take on some mechanical characteristics of the rubber to a certain degree. In particular, the concrete’s durability should increase when exposed to fluctuating temperature conditions due to the rubber additive. This experiment sets out to test crumb rubber as a concrete additive, cured under various atmospheric conditions. The effects shall be measured via a simple concrete compression test.

Unfortunately, several errors took place during experimental process that led to inconclusive results. However, it can be reasonably considered from testing Matrix One that the addition of crumb rubber …

Developing The Stress Strain Curves For An Epoxy Undergoing High Speed Impact, Stanford L. Howdyshell 7867559

Williams Honors College, Honors Research Projects

The Hopkinson Split Bar test can be used to accurately develop the relationship between the stress and strain a material undergoes during a high speed impact (rates of 1000/s). This information has many industrial uses, for example the auto industry can use this technology to analyze how materials will behave under crash-like circumstances. In this experiment the stress-strain curves were developed for the PC-Plumbing epoxy.

One of the variables that can be adjusted in the Split Hopkinson Bar test is the ration between the height of the sample and the width of the sample (Hs/Ds). This experiment investigated how three …

Diffusive Behavior Of Physically Cross-Linked Hydrogels, Morgan A. Stilke

Williams Honors College, Honors Research Projects

A hydrogel is a water swollen polymeric network that has the potential to transform a variety of biomedical applications because of its biocompatibility and water content. Unfortunately, hydrogels typically have poor mechanical robustness. The majority of the content is water, while the remaining structure consists of a physical network, a covalent network, or a combination of both, yielding strength and toughness. There are several strategies attempted to improve mechanical properties including double network hydrogels comprised of two interpenetrating networks: one being a highly crosslinked sacrificial network and the other being a weakly crosslinked network that maintains reversibility after deformation. However, …

Optimizing Solvent Blends For A Quinary System, Thomas L. Hoy

Williams Honors College, Honors Research Projects

The Department of Polymer Engineering had received a grant from the Keck foundation to produce a process in which hundreds of copolymers can be formulated, synthesized, analyzed and then extrapolated to produce the optimal polymer for the desired material property. This process involves synthesizing approximately fifty polymers in a custom apparatus, none of which necessarily have the same monomer components. This leads to issue of which solvent or blend of solvents to use that would sufficiently dissolve both monomers and the resulting copolymer. If the monomers are not completely dissolved, a homogenous reaction will be impossible and if the copolymer …

Effect Of Nanofiber Morphology On Pvdf Air Filter Performance, Andrew W. Marton

Williams Honors College, Honors Research Projects

Poly(vinylidene fluoride) (PVDF) can be formed into small nanofibers by electrospinning that are useful for a variety of applications. Air filters produced with PVDF are known to capture ionic particles with high efficiency. Existing studies have focused on the effects of electrospinning conditions on nanofiber morphology. In this study fibers were generated with varying morphologies. Air filters were then made from each sample and then characterized by TSI. Air filters were found to have increased resistances relative to their capture efficiencies according to particle diameter. Capture efficiencies did not correlate strongly with particle diameter, and the presence of beads in …

Reusable Adhesive Tapes From Electrospun Polymer Fibers, Vishal K. Chaurasia

Williams Honors College, Honors Research Projects

Many emerging applications demand an adhesive that has reusable properties. The adhesive must exhibit high adhesion strength to various surfaces and be able to be removed easily and then reapplied with minimal to no loss in adhesion strength. This work aims to tackle this problem by creating an adhesive tape fabricated by electrospinning polymer solutions onto a substrate. Electrospun adhesive nano/micro fibers have the ability to display the reusable characteristics desired. Several adhesive custom formulations were first developed and optimized for electrospinning. Then these formulations were successfully electrospun on to various substrates after much fine tuning of electrospinning parameters. The …