Polymer Science Commons^™

Electrode Materials, Thermal Annealing Sequences, And Lateral/Vertical Phase Separation Of Polymer Solar Cells From Multiscale Molecular Simulations, Cheng-Kuang Lee, Olga Wodo, Baskar Ganapathysubramanian, Chun-Wei Pao

Baskar Ganapathysubramanian

The nanomorphologies of the bulk heterojunction (BHJ) layer of polymer solar cells are extremely sensitive to the electrode materials and thermal annealing conditions. In this work, the correlations of electrode materials, thermal annealing sequences, and resultant BHJ nanomorphological details of P3HT:PCBM BHJ polymer solar cell are studied by a series of large-scale, coarse-grained (CG) molecular simulations of system comprised of PEDOT:PSS/P3HT:PCBM/Al layers. Simulations are performed for various configurations of electrode materials as well as processing temperature. The complex CG molecular data are characterized using a novel extension of our graph-based framework to quantify morphology and ...

Book Review: Controlled And Living Polymerizations: From Mechanisms To Applications, Jennifer M. Heinen

Jennifer M. Heinen

Controlled/living polymerization makes it possible to synthesize polymers of low polydispersity with a predefined molecular weight and specified chain architecture. Such polymers are desirable for a broad range of applications, including coatings, adhesives, and lubricants. Although living polymerization was first discovered in anionic polymerizations in 1956, several decades passed prior to the development of living polymerization techniques for carbocationic polymerization (1984) and ring-opening metathesis polymerization (1986). During the 1990s, several techniques were developed for controlled/living free radical polymerizations. The development of these techniques led to a dramatic increase in the number of research publications dedicated to improving the ...

An Industrial Process For The Production Of Nylon 6 6 Through The Step-Growth Reaction Of Adipic Acid And Hexamethylenediamine, David Wallace Jacobson

Chemical Engineering Undergraduate Honors Theses

A continuous, two stage, four reactor system process is presented here for the proposed purpose of nylon 6 6 manufacture at the rate of 85 million lbs per year. Report components include: process descriptions, simulation methods and results, economic analysis, EH&S considerations, process control descriptions, and a general recommendation for how to proceed with plans enclosed. The general design of the plant is a two stage system composed of one PFR used for the formation of nylon salt and low molecular weight nylon chains, followed by three CSTR’s used for increasing nylon molecular weight. The overall process has ...

Photoactive Properties Of Nanostructured Titania Modified Polyurethanes, Chao Chen

Electronic Thesis and Dissertation Repository

In order to enhance both the photoactivity and physical/mechanical properties of titania/polyurethane (PU) nanocomposites, in-situ polymerization and film casting were investigated. Both self-degrading PU foams and self-cleaning PU coatings were prepared. Functional monomers were prepared usingDMPA (2,2-dimethylolpropionic acid) functionalized anatse TiO₂ and P25 for integration into polyurethane foam with a "grafting-from" synthetic method. This technique was found to successfully reduce the agglomeration effect of titania nanoparticles inside the foams. In addition, the photodegradation rate was enhanced by > 120% over unmodified foam at an optimized loading of 3wt% DMPA functionalized anatase TiO₂. The presence of DMPA ...

Evaluating The Bond Behavior Between Frp And Grooved Concrete Specimens Using Single Shear Pull Out Test, John Omboko

Master's Theses (2009 -)

Surface preparation affects the bond behavior between Fiber Reinforcing Polymer (FRP) composite material and concrete. In this research, a special type of surface preparation known as grooving, which involves cutting transverse grooves, is conducted on concrete blocks (specimens) that are categorized as either Unfilled (U) or Filled (F). This idea is to ascertain how the grooves affect the strength of FRP-bonded-concrete specimen. These two categories are then benchmarked to control (C) specimens which do not have grooves on them. Category U specimens only have the epoxy applied on the concrete surface while category F specimens have epoxy applied on both ...

High-Density Non-Fouling Bioactive Coatings: Development And Characterization, Bonan Yu, Ramya Raman, Karl Schlike

Biomedical Engineering Western Regional Conference

No abstract provided.

Producing Food Packaging Printing Ink Via Green Emulsion Aggregation Method, Maryam Ataeefard, Shohre Rouhani

Journal of Applied Packaging Research

Digital printing will become more and more important in the packaging industry. Digital printing technology is growing because it allows the print suppliers to improve the level of service they offering to their customers, as well as, it opens new opportunities and helps them to make more money. Additives, dyestuffs, resin and other chemicals in packaging printing ink may influence safety of the food. Therefore, choosing suitable materials are very important in food packing ink. Over the last years, many printing ink manufacturers moved toward more sustainable inks. Drivers for this development, besides the resource scarcity and a higher legislative ...

Tunable Nanocomposite Membranes For Water Remediation And Separations, Sebastián Hernández Sierra

Theses and Dissertations--Chemical and Materials Engineering

Nano-structured material fabrication using functionalized membranes with polyelectrolytes is a promising research field for water pollution, catalytic and mining applications. These responsive polymers react to external stimuli like temperature, pH, radiation, ionic strength or chemical composition. Such nanomaterials provide novel hybrid properties and can also be self-supported in addition to the membranes.

Polyelectrolytes (as hydrogels) have pH responsiveness. The hydrogel moieties gain or lose protons based on the pH, displaying swelling properties. These responsive materials can be exploited to synthesize metal nanoparticles in situ using their functional groups, or to immobilize other polyelectrolytes and biomolecules. Due to their properties, these ...

Design Of Rubber Extraction Process From Tks Dandelion, Trevor A. Cody

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 ...

Synthesis Of Biopolymer Materials Tailored For Biological Applications, Nathan P. Birch

Doctoral Dissertations May 2014 - current

Biopolymers are able to address a wide variety of medical concerns from chronic wounds to stem cell cultivation to antibacterial and antifouling applications. They are non-toxic, biodegradable, and biocompatible, making them ideal candidates for creating green materials for biological applications. In this thesis, we cover the synthesis of two novel materials from the biopolymers, chitosan and pectin. Chitosan is a biocompatible antibacterial polycation and pectin is an anti-inflammatory polyanion with a strong propensity for hydrogen-bonding. The two chitosan:pectin materials, particles and hydrogels, explore some of the structures that can be created by tuning the electrostatic interactions between chitosan and ...

Deformation And Adhesion Of Soft Composite Systems For Bio-Inspired Adhesives And Wrinkled Surface Fabrication, Michael Imburgia

Doctoral Dissertations May 2014 - current

The study of soft material deformation and adhesion has broad applicability to industries ranging from automobile tires to medical prosthetics and implants. When a mechanical load is imposed on a soft material system, a variety of issues can arise, including non-linear deformations at interfaces between soft and rigid components. The work presented in this dissertation embraces the occurrence of these non-linear deformations, leading to the design of functional systems that incorporate a soft elastomer layer with application to bio-inspired adhesives and wrinkled surface fabrication. Understanding the deformation of a soft elastomer layer and how the system loading and geometry influence ...

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

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 ...

Stability And Retention Enhancement Of Low Fouling Polystyrene Sulfonic Acid (Pss) And Polyethylene Glycol (Peg) Blend Films With Silane Coupling Agents, Sean Stybel

Honors Research Projects

The goal of this research project was to apply silane coupling agents for enhanced stability and retention of a low fouling polymeric coating to an inorganic substrate. A blend of polystyrene sulfonic acid (PSS) and polyethylene glycol (PEG) was crosslinked in order to create a low fouling film. The film was prepared by spin coating a PSS-PEG solution on an inorganic substrate coated with a layer of a silane coupling agent (3-aminopropyltriethoxysilane, APTES, solution), followed by thermal curing. The research was limited to less than one year and only used lab equipment available at the University of Akron. Stability and ...

Characterization Of Polyurethane For Use As Substrate In Nanofiber Sensor For Biomedical Applications, Megan Theaker

Honors Research Projects

The purpose of this project is to begin to determine properties of polymer nanocomposites that make a suitable substrate for nanofiber sensors. In this work, sensitivity of a sodium ion selective sensor constructed with polyurethane was used as a benchmark for comparison with sensors constructed with nylon-6. The sensors were characterized using contact angle and chronoamperometry. Using an ANOVA analysis, the results showed that the multi-walled carbon nanotube type was a significant factor on sensor response both with and without additional functionalization of the polymer by calixarene. The weight percentage of polyurethane in the electrospinning solution was also statistically significant ...

Two-Photon Polymerization Of Soft Matter Composites, Yasser Albarakat

Undergraduate Honors Theses

With two-photon photopolymerization (2PP), it is possible to design and produce composite materials with three dimensional control and sub-micron precision, thanks to highly localized nonlinear process of polymerization. In this work, the feasibility of fabricating mesostructured composite particles with pre-defined shape and topology is examined. We explored polymerizable materials from both commercial sources and laboratory products as well as variable laser parameters, including pulse width and intensity along with dwell time, to find optimum conditions for 2PP. Later 2PP was performed on polymerizable materials containing quantum dots dispersion and the optical response of the resultant composite was characterized with spectroscopy ...

In Mold Flow Of Long Fibers In Compression Molding Process, Gleb Meirson

Electronic Thesis and Dissertation Repository

Long Fiber Thermoplastics (LFT) are promising new materials with high physical properties and low density. These high properties are obtained by embedding very long fibers (~100 mm) into a thermoplastic matrix. Such a high fiber length dictates the use of a compression molding process for manufacturing as the length of discontinuous fibers in injection molding is limited by pellet length.

LFT composites are of great interest for the automotive industry. These materials are already used in some interior and exterior car parts such as bumpers, seat structures, door module etc. This research is inspired by the desire to manufacture load ...

Nanostructured Morphologies In Glassy Polymer Networks, Brian Greenhoe

Dissertations

The body of this work describes a novel approach for the dispersion of multi-walled carbon nanotubes in a high T_g epoxy prepolymer matrix using a twin screw high-shear continuous reactor. The method demonstrated improves on previous dispersion methods in several ways. It offers increased efficiency through excellent heat transfer, while being solvent-less, scale-able, and tailorable to drive dispersion states to judiciously chosen dispersion states. Furthermore, it was shown that dispersion state and agglomerate morphology can be directed, in several ways, through processing conditions and also by controlling the matrix viscosity profile through cure. Broadband dielectric spectroscopy, optical hot-stage microscopy ...

Recent Approaches In Designing Bioadhesive Materials Inspired By Mussel Adhesive Protein, Pegah Kord Forooshani, Bruce P. Lee

Department of Biomedical Engineering Publications

Marine mussels secret protein-based adhesives, which enable them to anchor to various surfaces in a saline, intertidal zone. Mussel foot proteins (Mfps) contain a large abundance of a unique, catecholic amino acid, Dopa, in their protein sequences. Catechol offers robust and durable adhe-sion to various substrate surfaces and contributes to the curing of the adhesive plaques. In this article, we review the unique features and the key functionalities of Mfps, catechol chemistry, and strategies for preparing catechol-functionalized poly- mers. Specifically, we reviewed recent findings on the contributions of various features of Mfps on interfacial binding, which include coacervate formation, surface ...

Effect Of Surface Treatment On Liquid Adhesion Inside 3-D Structures, Madani A. Khan, Jeffrey Alston, Andrew Guenthner, Jacob Zavala

STAR (STEM Teacher and Researcher) Presentations

This study explores the relationship between chemical surface treatments on the interior of glass tubes and their resistance to fluid flow. By treating the interior of the tubes with functional silanes we can decrease or increase the interaction of the tube walls with the fluid column, which translates to changes in fluid column height for a given pressure differential. Resistance to fluid flow is quantified by using the tubes as integral parts of a barometric pressure column and measuring the changes in column height as the fluid is pulled into the tube by a set pressure differential. The barometric pressure ...

Studies On Nanocomposite Coating Produced By Laser-Assisted Process To Prevent Silicone Hydrogels From Bio-Fouling, Vishnuvardhana Wuppaladhodi

Electronic Thesis and Dissertation Repository

In this thesis, silver nanoparticles incorporated into polyvinylpyrrolidone (PVP) were deposited on silicone hydrogel to improve the hydrophilicity of the silicone hydrogel and prevent the growth of bacteria. Two different processes were employed to produce Ag nanoparticles: (1) Process-A is a photochemical reduction; (2) Process-B is laser ablation in liquid. Following that, MAPLE process was employed to deposit the Ag-PVP nanocomposites on the surface of silicone hydrogel. A solid-state pulsed laser (Nd:YAG) with a wavelength of 532 nm at a fluence of 50.4 mJ/cm² was used in the MAPLE system to deposit Ag-PVP nanocomposite coating. Our ...