Development Of Starch-Polyvinyl Alcohol (Pva) Biodegradable Film: Effect Of Cross-Linking Agent And Antimicrobials On Film Characteristics, 2017 Agricultural and Food Engineering Department, Indian Institute of Technology, Kharagpur
Development Of Starch-Polyvinyl Alcohol (Pva) Biodegradable Film: Effect Of Cross-Linking Agent And Antimicrobials On Film Characteristics, Aniket Satish More, Chandani Sen, Madhusweta Das
Journal of Applied Packaging Research
To satisfy the need of developing eco-friendly flexible antimicrobial packaging film with minimum use of synthetic chemical ingredients, the present study examined the efficacy of citric acid (CA) as cross-linking agent and essential oils (EOs), viz., cinnamon essential oil (CEO) and oregano essential oil (OEO) as natural antimicrobials in corn starch-polyvinyl alcohol (CS-PVA) film. Compared to film prepared from filmogenic solution (FS) containing 75 kg CS+8.75 kg PVA+24.6 kg glycerol per m3 FS, film additionally containing CA at 0.07 kg/kg CS indicated 95% higher ultimate tensile strength (UTS) and 27% lower water vapor ...
Effects Of Lignin As A Stabilizer Or Antioxidant In Polyolefins, 2017 The University of Western Ontario
Effects Of Lignin As A Stabilizer Or Antioxidant In Polyolefins, Afsana S. Kabir
Electronic Thesis and Dissertation Repository
Lignin, a major component of biomass, is an attractive alternative to hindered phenol-based antioxidants for polymers due to its renewable nature and naturally occurring hindered phenolic structure. In this study, for the first time, lignin de-polymerization was explored as a promising approach to improve the reactivity of the lignin-based antioxidants for polymers (polyethylene, PE and polypropylene, PP). A proprietary hydrolytic de-polymerization process was utilized to increase the antioxidant activity of two types of technical lignin: kraft lignin, KL (a by-product from the pulp and paper industry) and hydrolysis lignin, HL (a by-product from the pre-treatment processes in cellulosic ethanol plants ...
Additive Manufacturing Process Of 3d Polyaniline Transducers Via Direct Ink Writing, 2017 The University of Western Ontario
Additive Manufacturing Process Of 3d Polyaniline Transducers Via Direct Ink Writing, Frederick Benjamin Holness
Electronic Thesis and Dissertation Repository
Electroactive polymers exhibit a change in properties, typically size or shape, in response to electrical stimuli. One class of electroactive polymer of particular interest are the conjugated polymers, whose conjugated backbone structure imparts electrical conductivity. However, this structure imposes processing limitations restricting their form to 2D structures. To overcome this, we develop specially formulated polyaniline- based blends via counter-ion induced thermal doping for the fabrication of 3D conductive structures via direct ink writing. This approach employs multi-material extrusion for the production of structures with passive and active features, rapid device fabrication, and improved design freedom. A model of the thermal ...
Plasticization And Reinforcement In A Boron Cage Compound Polyurethane Nanocomposite: A Dielectric Study, 2017 Iowa State University
Plasticization And Reinforcement In A Boron Cage Compound Polyurethane Nanocomposite: A Dielectric Study, J. Liu, X. Zhang, D. E. Bowen, Nicola Bowler
In order to control and modify the physical properties of nanocomposite systems, it is essential to understand the nano-filler/polymer structure–property relationships. Boron cage compounds (BCCs) are a class of icosahedral, closed cage molecules that are of interest due to their high boron content, their inherent neutron absorbing/shielding properties, their potential ability to act as molecular nano-particles and their ability to significantly improve the thermal stability of polymers in which they have been incorporated. When the BCC n-hexylcarborane is blended with a polybutadiene (PBD)/polyurethane (PU) segmented copolymer (EN8) an increase in the glass transition (Tg) temperature of ...
Electrothermal Lifetime Prediction Of Polyimide Wire Insulation With Application To Aircraft, 2017 Iowa State University
Electrothermal Lifetime Prediction Of Polyimide Wire Insulation With Application To Aircraft, Peter R. Hondred, Nicola Bowler, Michael R. Kessler
This work investigates the electrothermal lifetime of a commonly used polyimide wire insulation material, Kapton®, through the use of thermogravimetry (TG) and breakdown voltage testing. From TG, an isoconversional model-free kinetic evaluation was used to obtain a relationship between the activation energies of degradation for Kapton as a function of weight loss. By relating the electrical life theory and the TG theory through the model defined by Toop (IEEE Trans. Dielectr. Electr. Insul. 1971, 6, 2), the electrothermal lifetime of Kapton has been calculated for conditions of 12 and 14.7 kV over a temperature range of 250–400°C ...
Dynamics Of Poly(Methyl Methacrylate)–Montmorillonite Nanocomposites: A Dielectric Study, 2017 Iowa State University
Dynamics Of Poly(Methyl Methacrylate)–Montmorillonite Nanocomposites: A Dielectric Study, Weixing Sun, Li Li, Michael R. Kessler, Nicola Bowler
The effect of varying amounts of montmorillonite (MMT) filler (in weight ratios of 100/0, 100/5, and 100/10) on the molecular dynamics and polarization of atactic poly(methyl methacrylate) (PMMA) is investigated using broad-band dielectric spectroscopy from 10−2 to 106 Hz and at temperatures from 30 to 140 °C. The experimental data were analyzed with the sum of Havriliak–Negami (HN) functions and a power-law conduction term. The characteristic frequency, activation energies, and dielectric strength of PMMA/MMT nanocomposites were analyzed. As MMT content increases, a Maxwell–Wagner–Sillars (MWS) relaxation emerges in the nanocomposites and the ...
Structure-Force Field Generator For Molecular Dynamics Simulations, 2017 Universidad de Los Andes - Colombia
Structure-Force Field Generator For Molecular Dynamics Simulations, Carlos M. Patiño, Lorena Alzate, Alejandro Strachan
The Summer Undergraduate Research Fellowship (SURF) Symposium
Atomistic and molecular simulations have become an important research field due to the progress made in computer performance and the necessity of new and improved materials. Despite this, first principle simulations of large molecules are still not possible because the high computational time and resources required. Other methods, such as molecular dynamics, allow the simplification of calculations by defining energy terms to describe multiple atom interactions without compromising accuracy significantly. A group of these energy terms is called a force field, and each force field has its own descriptions and parameters. The objective of this project was to develop a ...
Usage Of Fomblin Y To Improve Water Repellence Of Surface Coatings, 2017 California State University - Long Beach
Usage Of Fomblin Y To Improve Water Repellence Of Surface Coatings, Shawn Pj Kirby, Jeffrey Alston, Andrew Guenthner
STAR (STEM Teacher and Researcher) Presentations
Fluoro-Decyl POSS (FDP) has shown strong potential as a water repellant surface coating. Additionally, Fomblin is a solvent believed to have the ability to control the crystallization of POSS compounds on surfaces. Controlling the crystallization is key to improving water repelling abilities of surfaces. Thus, dip coating FDP and Fomblin onto surfaces is being investigated for water repulsion, mechanical stability, and deposition feasibility. Relative water repelling abilities of different coatings were determined by measuring contact angle of surfaces with water. Coatings with and without POSS and Fomblin were compared. It was shown that the surfaces treated with both POSS and ...
Cellulose Reinforced Thermoplastic Composites By In-Situ Ring-Opening Polymerization, 2017 University of Southern Mississippi
Cellulose Reinforced Thermoplastic Composites By In-Situ Ring-Opening Polymerization, Shahab Kashani Rahimi
Over the past two decades, the increasing concern about the negative environmental impacts of synthetic materials has led to rising interests in utilizing renewable natural resources to develop polymer materials with comparable properties and performance to their synthetic counterparts. One of the major fields of interest is polymer composites where the replacement of synthetic fibers with bio renewable natural fibers is of great potential. However, the processing difficulties, in terms of fiber dispersion and thermal stability have limited the application of cellulosic fibers to polymers with low processing temperatures which are mostly hydrophobic polymers. As a result, the true reinforcing ...
Membranes For Food And Bioproduct Processing, 2017 University of Arkansas, Fayetteville
Membranes For Food And Bioproduct Processing, Alexandru Marius Avram
Theses and Dissertations
Modified membranes for process intensification in biomass hydrolysis
Production of biofuels and chemicals from lignocellulosic biomass is one of the leading candidates for replacement of petroleum based fuels and chemicals. However, conversion of lignocellulosic biomass into fuels and chemicals is not cost effective compared to the production of fuels and chemicals from crude oil reserves. Some novel and economically feasible approaches involve the use of ionic liquids as solvents or co-solvents, since these show improved solvation capability of cellulose over simple aqueous systems. Membranes offer unique opportunities for process intensification which involves fractionation of the resulting biomass hydrolysate leading to ...
Molecular Dynamics Modeling And Simulation Of Bitumen Chemical Aging, 2017 University of Nebraska - Lincoln
Molecular Dynamics Modeling And Simulation Of Bitumen Chemical Aging, Farshad Fallah
Civil Engineering Theses, Dissertations, and Student Research
Chemical aging of asphalt binder leads to significant changes in its mechanical and rheological properties, resulting in poor pavement behavior and distress. Various laboratory methods have been used to simulate asphalt aging during the service life of the pavement. However, controversy exists regarding the capability of these methods to predict field aging, as various factors interact with the pavement during service and the mechanism behind aging is not fully understood. The two main outcomes of chemical aging are oxidation of asphalt molecules, and change in asphalt SARA (saturate, aromatic, resin, and asphaltene) fractions. Reaction of oxygen with asphalt components forms ...
A Study In The Use Of Elastic Materials In Expandable Containment Units, 2017 Liberty University
A Study In The Use Of Elastic Materials In Expandable Containment Units, Andrew J. Eisenman, Joby Anthony Iii, David Satagaj
Montview Liberty University Journal of Undergraduate Research
The rigidity of materials in conjunction with the aspect of elasticity has been a concern of modern technologies and construction in recent centuries because of the advantages that expandable storage would bring to the fields of containment units with respect to population growth and space exploration. The world population is currently growing at an exponential rate, and as our population grows, the more important it will become to have containment units that can both contain large volumes of material as well as minuscule amounts of material without wasting space. In order accomplish this, we will need a new type of ...
Function And Biodegradation In Soil Of Bioplastic Horticultural Containers Made Of Pla-Biorestm Composites, 2017 Iowa State University
Function And Biodegradation In Soil Of Bioplastic Horticultural Containers Made Of Pla-Biorestm Composites, James Schrader, Kenneth Mccabe, William Graves, David Grewell
William R Graves
Container-crops horticultural industries rely almost exclusively on petroleum-based plastic containers for modern production systems. Containers made of these materials fulfill all of the functions required during crop production, and perform better than containers made of clay, peat, and other natural materials, but the source of the plastic materials (fossil carbon), their lack of biodegradability, and their end-of-life disposal (97% end up in landfills) are major obstacles to sustainability. Although function and efficiency are among the most important aspects in determining the best materials for horticultural containers, there is no need for containers to persist in the environment for decades when ...
A Graph-Based Formulation For Computational Characterization Of Bulk Heterojunction Morphology, 2017 Iowa State University
A Graph-Based Formulation For Computational Characterization Of Bulk Heterojunction Morphology, Olga Wodo, Srikanta Tirthapura, Sumit Chaudhary, Baskar Ganapathysubramanian
To improve the efficiency of organic solar cells, it is essential to understand the role of morphology and to tailor fabrication process to get desired morphologies. In this context, a comprehensive set of computational tools to quantify and classify the 2D/3D heterogeneous internal structure of thin films is invaluable. We present a graph-based framework to efficiently compute a broad suite of physically meaningful morphology descriptors. These morphology descriptors are further classified according to the physical subprocesses within OSCs – photon absorption, exciton diffusion, charge separation, and charge transport. This approach is motivated by the equivalence between a discretized 2D/3D ...
The Relationship Between Structural Parameters And Mechanical Properties Of Cactus Spines, 2017 California Polytechnic State University, San Luis Obispo
The Relationship Between Structural Parameters And Mechanical Properties Of Cactus Spines, Jorge Armando Martinez, Pamela Liz Szeto, Theresa Mae Stewart
Considering an increasing interest in renewable, biodegradable resources that exhibit excellent mechanical properties, 24 species of cactus spines were investigated using three-point bend testing, X-ray diffraction (XRD) for structural parameters, and scanning electron microscopy (SEM) to analyze fracture surfaces. Additionally, a density of about 1.3 g/cm3 was measured for each spine utilizing the displacement method, closely matching existing data from literature. The flexural modulus varied greatly between species, ranging from 1.22 GPa (Echinocactus polycephalus) to 43.58 GPa (Stenocereus thurberi). In addition, flexural strength and strain to failure was also measured for each spine. XRD analysis of ...
Feasibility Of Using 3d Printed Molds For Thermoforming Thermoplastic Composites, 2017 University of Maine
Feasibility Of Using 3d Printed Molds For Thermoforming Thermoplastic Composites, Sunil Bhandari
Electronic Theses and Dissertations
This thesis presents a novel combined experimental and numerical mechanics approach for characterizing 3D printed thermoplastic materials by the fused deposition modeling process for thermoforming thermoplastic composites. The implications of this work are:
- a methodology for model-based performance evaluation of 3D printed structural parts, and
- an improved design of 3D printed molds for composites manufacturing, which has potential for material innovations and scaled-up applications in additive manufacturing.
The thesis formulates basic criteria for selection of thermoplastic polymer used for the 3D printed mold based on forming temperatures. The thesis creates a lattice and shell finite element model of the 3D ...
Modulation Of Cell Behaviors On Photo-Crosslinked Polymer Networks And Polymer Spherulites, 2017 University of Tennessee, Knoxville
Modulation Of Cell Behaviors On Photo-Crosslinked Polymer Networks And Polymer Spherulites, Jinbo Dou
This dissertation presents novel biodegradable and photo-crosslinkable poly(-caprolactone) acrylates (PCLAs) to achieve polymer networks with controllable surface chemistry, stiffness, and topographical features, as well as crystallization-induced PCL, poly(3-hydroxybutyrate) (PHB) and poly(L-lactic acid) (PLLA) surfaces for investigating cell-material interactions. Chapter I reviews the recent progress of injectable polymeric biomaterials in the last decade for various tissue engineering applications. Chapter II investigates the variation of thermal and mechanical properties of PCL triacrylate (PCLTA) networks with different crosslinking time, and further studies the smooth muscle cell (SMC) responses to these networks. Chapter III studies the SMC responses to hydrolyzed PCLTA ...
Renewable And Abundant Battery Components, 2017 University of Tennessee, Knoxville
Renewable And Abundant Battery Components, Jordan T. Sutton, Daniel San Roman, Austin Thomas, Daniel Kitsmiller, Alec Affolter
University of Tennessee Honors Thesis Projects
No abstract provided.
Effect Of Chain Rigidity On Network Architecture And Deformation Behavior Of Glassy Polymer Networks, 2017 University of Southern Mississippi
Effect Of Chain Rigidity On Network Architecture And Deformation Behavior Of Glassy Polymer Networks, Kyler Reser Knowles
Processing carbon fiber composite laminates creates molecular-level strains in the thermoset matrix upon curing and cooling which can lead to failures such as geometry deformations, micro-cracking, and other issues. It is known strain creation is attributed to the significant volume and physical state changes undergone by the polymer matrix throughout the curing process, though storage and relaxation of cure-induced strains remain poorly understood. This dissertation establishes two approaches to address the issue. The first establishes testing methods to simultaneously measure key volumetric properties of a carbon fiber composite laminate and its polymer matrix. The second approach considers the rigidity of ...
An Investigation Of The Use Of Cerium And Polyhedral Oligomeric Silsesquioxanes For The Protection Of Polymeric Epoxy Compounds In The Low Earth Orbit Environment, 2017 University of Southern Mississippi
An Investigation Of The Use Of Cerium And Polyhedral Oligomeric Silsesquioxanes For The Protection Of Polymeric Epoxy Compounds In The Low Earth Orbit Environment, Jessica Miriam Piness
Low Earth orbit presents many hazards for composites including atomic oxygen, UV radiation, thermal cycling, micrometeoroids, and high energy protons. Atomic oxygen and vacuum ultraviolet radiation are of concern for space-bound polymeric materials as they degrade the polymers used as matrices for carbon fiber composites, which are used in satellites and space vehicles due to their high strength to weight ratios. Epoxy-amine thermosets comprise a common class of matrix due to processability and good thermal attributes. Polyhedral oligomeric silsesquioxanes (POSS) have shown the ability to reduce erosion in polyimides, polyurethanes, and other polymers when exposed to atomic oxygen. The POSS ...