Polymer and Organic Materials Commons^™

Occurrence Of Reverse Side Effects In Corona Treatment Of Dispersion-Coated Paperboard And Its Influence On Grease Barrier Properties, Sami-Seppo Ovaska, Ringaudas Rinkunas, Tadeusz Lozovksi, Robertas Maldzius, Jonas Sidaravicius, Leena-Sisko Johansson, Monika Österberg, Kaj Backfolk

Journal of Applied Packaging Research

The uncoated side of dispersion-barrier-coated paperboards was exposed to positive and negative direct current corona treatments in order to confirm the occurrence of backside treatment and clarify its effects on the usability of the paperboard. The main component of the coating dispersions was hydroxypropylated potato starch and the effects of talc and styrene-butadiene latex additions on backside treatment were evaluated. Coatings with a high talc proportion showed excellent initial grease resistance, but corona-induced strikethroughs caused a drastic decrease in grease penetration time. The root-mean-square roughness measurements revealed moderate surface roughening at the backside, indicating thus backside treatment. The alterations in …

Wide Bandgap Organo‐Lead Trihalide Perovskites For Solar Cells, Miao Hu

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Methylammonium lead trihalide perovskite (MAPbX3, where MA is methylammonium, and X is a halide)-based solar cells have been extensively investigated recently, with a demonstrated and certified solar power conversion efficiency (PCE) exceeding 20%. To further boost the PCE beyond the Schockley–Queisser limit, tandem structured solar cells have been investigated based on integrating MAPbX3 and the lower bandgap solar cells. Although the best reported efficiency for this type of tandem cells is not close to the theoretically achievable value, mixed-halide perovskite MAPbBrxI3–x is still one of the most promising candidates as the wide-bandgap light absorber for the tandem application to match …

Technical Developments In Fish Exclusion, Guidance, And Collection Materials, A. L. Peters

International Symposium on Hydraulic Structures

Construction of mills, dams and other structures in rivers and streams, and the withdrawal of water for irrigation or cooling industrial facilities vital to social and economic progress, have impacted the survival of marine life. Barriers and guidance or collection nets can protect fish and aquatic species while allowing water to flow unimpeded for commercial and industrial use. However, nets can attract aquatic growth, fill with debris, degrade with environmental stress, and be expensive to operate and maintain.

A closer look at the technical developments of materials and net designs in diverse settings can offer guidance that will be of …

Improving The Mechanical Performance Of 3d Printed Parts Using Fused Filament Fabrication, Inderpreet Binning

Industrial and Manufacturing Engineering

The 3D printing industry has seen rapid growth in the last 10 years and has been called the next industrial revolution. There are several different processes used in 3D printing, but the most popular process is called Fused Filament Fabrication (FFF) or Fused Deposition Modeling (FDM). This is the process where (most commonly) plastic filament enters a nozzle, is heated to a semi-liquid state, and then deposited into a pattern to create a print. One major drawback to this process is that the prints are anisotropic. This means that the strength of the print varies with the orientation that it …

Solution Casting And Mechanical Testing Of Arabinan-Cellulose Nanocomposites, Kevin Su, Alina Lusebrink

Materials Engineering

The purpose of this work was to investigate methods to produce consistent, reliable, and testable thin films of arabinan-cellulose nanocomposites. Mechanical properties and composition of the Opuntia ficus-indica cactus spines served as motivation for this research. The high specific strength and stiffness, biodegradability, and sustainability of these spines inspired the creation of composites fabricated from the same materials found in cactus spines: arabinan and nanocrystalline cellulose (NCC). Arabinan serves as the matrix material and NCC as the reinforcement. To explore the feasibility of using a non-toxic solvent, different solution casting techniques with water as a solvent were investigated. Ultrasonication was …

Effect Of Metal Organic Framework Concentration On The Crystallization Of Pla-Al-Mof Composites, Eric Futak, Jeffrey Norton, Jessie O'Connell, Nestor Vazquez

Materials Engineering

Poly(lactic acid) (PLA), a well-known biopolymer, is lacking in barrier properties and toughness. The research goal of this project is to look at the crystallinity of PLA when combined with metal organic framework (MOF). It is speculated that MOF has an effect on PLA chain mobility, and therefore crystallinity. In this study, aluminum MOF was added to PLA in varying concentrations (0, 0.5, 1, 2, 5, 10, and 20 wt%) to observe the crystallinity of the composite. The resulting PLA-Al-MOF composite films were characterized using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron …

Design And Testing Of A Top Mask Projection Ceramic Stereolithography System For Ceramic Part Manufacturing, Dylan Robert De Caussin

Master's Theses

Ceramic manufacturing is an expensive process with long lead times between

the initial design and final manufactured part. This limits the use of ceramic as a viable material unless there is a large project budget or high production volume associated with the part. Ceramic stereolithography is an alternative to producing low cost parts through the mixing of a photo curable resin and ceramic particles. This is an additive manufacturing process in which each layer is built upon the previous to produce a green body that can be sintered for a fully dense ceramic part.

This thesis introduces a new approach …

Manufacturing And Characterization Of Poly (Lactic Acid)/Carbon Black Conductive Composites For Fdm Feedstock: An Exploratory Study, Dylan Fitz-Gerald, Justin Boothe

Materials Engineering

This exploratory study developed methods of manufacturing and characterizing the electrical properties of small batches of conductive composite feedstock for the Fused Deposition Modeling (FDM) manufacturing process, commonly known as 3D printing. We utilized a solution casting process of Poly(lactic acid) (PLA) (Grade 4043D, NatureWorks, LLC.) and Carbon Black (CB) (Vulcan® XC72, Cabot Corp.) in chloroform. The resulting composite precursor was cryogenically treated with liquid nitrogen and milled in a coffee grinder in order to achieve particles that could be fed into the extruder. Composite precursors were dried in a vacuum oven at an elevated temperature of 38°C. Filaments were …

Low-Cost Prosthetic Transfemoral Socket, Emelie Deans, Joshua Ledgerwood, Leah Moore, Shaina Jung, Kristen Temnyk

Mechanical Engineering

The goal of this senior project was to design and fabricate a low-cost adjustable prosthetic socket for above the knee amputees. This low-cost consideration was incorporated with the original intent to be used in Fiji, however, this changed to the Dominican Republic. It became clear that the need for an adjustable socket was more as a transitional socket. This transitional socket would be used for the first 6 -12 months upon amputation because this when the most amount of volume fluctuation occurs. The project sponsor, LIM Innovations, has already designed the Infinite Socket which contains four main functioning parts: baseplate, …

Design, Testing, Analysis, And Material Properties Of Carbon Fiber Reinforced Polymers, Andrew Miner, Simon Jones

Rose-Hulman Undergraduate Research Publications

Rose-Hulman Institute of Technology excels in many fields, however in the field of Carbon Fiber Reinforced Polymers (CFRPs) there is a significant lack of knowledge. Over the 2015 summer I started accumulating and building a knowledge base for the institute to help future students who have interest in this ever expanding field. This report covers many of the learnings I found in the structures of fiber reinforced polymers, manufacturing processes and controls, testing procedures and standards, important considerations in the design process of CFRPs, and analysis capabilities and methods. This report is organized as a series of short guides to …

Synthesis Of Acceptors For Use In Donor-Acceptor Copolymers And Characterization Of These Polymers, William D. Walker

Honors Theses

In this thesis, a selenium-derivatized acceptor was synthesized to examine the heavy atom effects of selenium on the position of the frontier molecular orbitals (HOMO/LUMO band gap) as opposed to sulfur in a donor-acceptor copolymer for use in light harvesting and detection applications. Over the course of this research, standard operating protocols for ultraviolet-visible (UV-Vis-NIR) and Fourier transform infrared (FT-IR) spectroscopies, as well as cyclic voltammetry (CV) characterization techniques were established. Once synthesized, the polymers were characterized through use of the established characterization protocols. The selenium-derivatized polymer exhibited a bathochromic shift compared to the sulfur analogue, with a solid-state absorption …

The Effect Of Cure Rate On Glassy Polymer Networks, Kristen M. Van De Voorde

Honors Theses

The formation of glassy polymer networks such as epoxy-amine systems may be altered by varying the temperature ramp rate that is used to cure the system. As a result, the physical and mechanical properties of the network may be changed. This work synthesized the epoxy resins diglycidyl ether of bisphenol A (DGEBA) with the amine curing agent 4,4-diaminodiphenyl sulfone (4,4’-DDS) from 35°C to 180°C using varying temperature ramp rates. Mechanical and structural properties of these samples were then analyzed to determine the effect the different temperature ramp rates had on the formation and properties of the thermoset matrix. These aspects …

Biopolymeric Mucin And Synthetic Polymer Analogs: Their Structure, Function And Role In Biomedical Applications, Sundar Prasanth Authimoolam, Thomas D. Dziubla

Chemical and Materials Engineering Faculty Publications

Mucin networks are viscoelastic fibrillar aggregates formed through the complex self-association of biopolymeric glycoprotein chains. The networks form a lubricious, hydrated protective shield along epithelial regions within the human body. The critical role played by mucin networks in impacting the transport properties of biofunctional molecules (e.g., biogenic molecules, probes, nanoparticles), and its effect on bioavailability are well described in the literature. An alternate perspective is provided in this paper, presenting mucin’s complex network structure, and its interdependent functional characteristics in human physiology. We highlight the recent advances that were achieved through the use of mucin in diverse areas of bioengineering …

Strain Effects On The Work Function Of An Organic Semiconductor, Yanfei Wu, Annabel R. Chew, Geoffrey A. Rojas, Gjergji Sini, Greg Haugstad, Alex Belianinov, Sergei V. Kalinin, Hong Li, Chad Risko, Jean-Luc Brédas, Alberto Salleo, C. Daniel Frisbie

Chemistry Faculty Publications

Establishing fundamental relationships between strain and work function (WF) in organic semiconductors is important not only for understanding electrical properties of organic thin films, which are subject to both intrinsic and extrinsic strains, but also for developing flexible electronic devices. Here we investigate tensile and compressive strain effects on the WF of rubrene single crystals. Mechanical strain induced by thermal expansion mismatch between the substrate and rubrene is quantified by X-ray diffraction. The corresponding WF change is measured by scanning Kelvin probe microscopy. The WF of rubrene increases (decreases) significantly with in-plane tensile (compressive) strain, which agrees qualitatively with density …

Aging Assessment Of High Voltage Single Component Room Temperature Vulcanized Silicone Rubber (Rtv-1) Subjected To Aqueous Salt, Monika Bleszynski

Electronic Theses and Dissertations

Single component room temperature vulcanized (RTV-1) silicone based caulk used in high voltage insulators and other applications is frequently subjected to environmental pollutants. Aging of RTV-1 silicone rubber is the result of various stressors, including environmental aging conditions such as UV, acid, and salt exposure from ocean mist. Loss of hydrophobicity due to damage of the hydrophobic methyl groups, as well as loss of mechanical strength due to depolymerization via hydrolysis as a result of aqueous salt exposure were the two main factors of material aging assessed in this work. Multiple RTV-1 formulations were initially assessed for resistance to aging …

Equi-Biaxial Fatigue Behaviour Of Magnetorheological Elastomers In Magnetic Fields, Yanfen Zhou, Mark Johnson, Shipeng Wen, Tony Betts, Stephen Jerrams

Articles

The equi-biaxial fatigue behaviour of silicone based magnetorheological elastomers (MREs) in external magnetic fields was studied. Wöhler curves relating fatigue life to stress amplitude and dynamic stored energy for MREs with a range of magnetic particle contents were derived. It was found that the fatigue life of MREs in magnetic fields was higher than that without magnetic fields. Under constant stress amplitude conditions, the presence of magnetic fields resulted in longer times for the samples to undergo large deformations and thus complex modulus (E*) decreased at a slower rate during the fatigue process, especially for low stress amplitudes. MRE samples …

Mechanical Testing Of Fused Filament 3-D Printed Components For Distributed Manufacturing, Nagendra Gautam Tanikella

Dissertations, Master's Theses and Master's Reports

Fused filament fabrication (FFF)-based open-source 3-D printers offer the potential of decentralized manufacturing both in developing and developed countries. Unfortunately, a severe lack of data and standards relating to material properties and printed components limit this potential. This thesis first investigates the mechanical properties of a wide-range of FFF materials and provides a database of mechanical strength of the materials tested. The results demonstrate that the tensile strength of a 3-D printed specimen depends largely on the mass of the specimen, which provides a means to estimate the strength of 3-D printed components. Then this information is used to evaluate …

Bioluminescent Magnetic Nanoparticles As Potential Imaging Agents For Mammalian Spermatozoa, Erick Salvador Vasquez, Jean M. Feugang, Scott T. Willard, Peter L. Ryan, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

Background: Nanoparticles have emerged as key materials for developing applications in nanomedicine, nanobiotechnology, bioimaging and theranostics. Existing bioimaging technologies include bioluminescent resonance energy transfer-conjugated quantum dots (BRET-QDs). Despite the current use of BRET-QDs for bioimaging, there are strong concerns about QD nanocomposites containing cadmium which exhibits potential cellular toxicity.

Results: In this study, bioluminescent composites comprised of magnetic nanoparticles and firefly luciferase (Photinus pyralis) are examined as potential light-emitting agents for imaging, detection, and tracking mammalian spermatozoa. Characterization was carried out using infrared spectroscopy, TEM and cryo-TEM imaging, and ζ-potential measurements to demonstrate the successful preparation of these nanocomposites. Binding …

The Role Of Microbial Exopolymers In Determining The Fate Of Oil And Chemical Dispersants In The Ocean, Antonietta Quigg, Uta Passow, Wei-Chun Chin, Chen Xu, Shawn Doyle, Laura Bretherton, Manoj Kamalanathan, Alicia K. Williams, Jason B. Sylvan, Zoe V. Finkel, Anthony H. Knap, Kathleen A. Schwehr, Saijin Zhang, Luni Sun, Terry L. Wade, Wassim Obeid, Patrick G. Hatcher, Peter H. Santschi

Chemistry & Biochemistry Faculty Publications

The production of extracellular polymeric substances (EPS) by planktonic microbes can influence the fate of oil and chemical dispersants in the ocean through emulsification, degradation, dispersion, aggregation, and/or sedimentation. In turn, microbial community structure and function, including the production and character of EPS, is influenced by the concentration and chemical composition of oil and chemical dispersants. For example, the production of marine oil snow and its sedimentation and flocculent accumulation to the seafloor were observed on an expansive scale after the Deepwater Horizon oil spill in the Northern Gulf of Mexico in 2010, but little is known about the underlying …

Evaluation Of Flocculation, Sedimentation, And Filtration For Dewatering Of Algal Biomass, Nicholas A. Rhea

Theses and Dissertations--Biosystems and Agricultural Engineering

Algae can be used as a feedstock for agricultural fertilizers, livestock/poultry feeds, anaerobic digestion, and biofuel production. Regardless of the end product, water removal is necessary and difficult to do cost effectively. For each product the requirements for moisture content (or solids content) vary, such that a desirable water removal strategy would need to be adaptable to varying levels of water removal. Flocculation, with sedimentation and drying was evaluated as a possible strategy for algae dewatering. Anionic and nonionic flocculants are known to be ineffective at flocculating algal culture, which was confirmed for this case by electro-osmotic flow testing of …