Polymer and Organic Materials Commons^™

Triperyleno[3,3,3]Propellane Triimides: Achieving A New Generation Of Quasi-D3h Symmetric Nanostructures In Organic Electronics, Lingling Lv, Josiah Roberts, Chengyi Xiao, Zhenmei Jia, Wei Jiang, Chad Risko, Lei Zhang

Chemistry Faculty Publications

Rigid three-dimensional (3D) polycyclic aromatic hydrocarbons (PAHs), in particular 3D nanographenes, have garnered interest due to their potential use in semiconductor applications and as models to study through-bond and through-space electronic interactions. Herein we report the development of a novel 3D-symmetric rylene imide building block, triperyleno[3,3,3]propellane triimides (6), that possesses three perylene monoimide subunits fused on a propellane. This building block shows several promising characteristics, including high solubility, large π-surfaces, electron-accepting capabilities, and a variety of reactive sites. Further, the building block is compatible with different reactions to readily yield quasi-D_3h symmetric nanostructures (9, …

Novel Low Shear 3d Bioreactor For The Scaled Production Of High Purity Human Mesenchymal Stem Cells, Andrew Burns

KGI Theses and Dissertations

Human mesenchymal stem cells are an ideal candidate for stem cell therapies. They have been researched since the 1960’s and can differentiate into many desired functional cell types without undergoing teratogenesis. However, higher yields are needed for a marketable, successful stem cell therapy. To accomplish this, cells will have to be cultured to expand them to therapeutically relevant dosages for multiple patients. Bioreactor production is an ideal method to solve this problem.

The aim of this thesis is to test and validate a novel bioreactor for the cultivation of human mesenchymal stem cells. In this work, we investigate a novel …

Design And Control Of Fiber Encapsulation Additive Manufacturing, Matt Saari

Mechanical Engineering Research Theses and Dissertations

This work presents the design, development, and analysis of the Fiber Encapsulation Additive Manufacturing (FEAM) system developed at the Laboratory for Additive Manufacturing Robotics \& Automation at the Lyle School of Engineering at Southern Methodist University. The innovation introduced by FEAM is the ability to insert a continuous fiber of different material into the flowing extrudate. Correctly positioning the fiber feed inside the extrudate while turning the fiber in arbitrary directions is a critical aspect of the technology. This will allow for the full exploitation of the capabilities of the FEAM technology to produce robotic components that actuate and sense. …

A Model-Based Framework For The Smart Manufacturing Of Polymers, Santiago D. Salas Ortiz

LSU Doctoral Dissertations

It is hard to point a daily activity in which polymeric materials or plastics are not involved. The synthesis of polymers occurs by reacting small molecules together to form, under certain conditions, long molecules. In polymer synthesis, it is mandatory to assure uniformity between batches, high-quality of end-products, efficiency, minimum environmental impact, and safety. It remains as a major challenge the establishment of operational conditions capable of achieving all objectives together. In this dissertation, different model-centric strategies are combined, assessed, and tested for two polymerization systems.

The first system is the synthesis of polyacrylamide in aqueous solution using potassium persulfate …

Highly Flame-Retardant Rigid Polyurethane Foams Prepared Using Corn Oil, Camila Muliterno Zequine

Electronic Theses & Dissertations

One of the biggest catastrophic problems worldwide is the structural fire that destroys properties, durable goods and lives. Polyurethanes are one of the most important polymers because of the widely use in industrial applications, such as thermal insulation, coating, construction and automobiles. However, polyurethane foams have the disadvantage of being flammable. Most of the starting materials for the production of polyurethanes are derivate from petroleum-based resources, which generates environmental and governmental problems. In this study, bio-based rigid polyurethane foams were synthesized using corn oil. First, commercial corn oil was fully epoxidized to be used in the synthesis of flame-retardant rigid …

Synthesis And Characterization Of Corn Oil Based Polyol And Its Application For Rigid Flame Retardant Polyurethane Foams, Sneha Ramanujam

Electronic Theses & Dissertations

A novel bio-based polyol was synthesized using corn oil and 2-mercaptoethanol via thiol-ene reaction as an alternative to petroleum-based polyol for the synthesis of polyurethane foams. The polyol was analyzed using wet chemical techniques to obtain a hydroxyl number and the viscosity of the polyol. Infrared spectroscopy and gel permeation chromatography were used to confirm the structural properties of the foams. Flame-retardant polyurethane foams were prepared by the addition of different concentrations of dimethyl methyl phosphonate (DMMP) in the final foam composition. The effect of DMMP on the thermo-mechanical properties of the polyurethane foams was analyzed. The TGA analysis showed …

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi S. Patel

University Scholar Projects

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi Patel

Honors Scholar Theses

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …

Fabrication And Characterization Of Collagen-Polypyrrole Constructs Using Direct-Ink Write Additive Manufacturing, Rooshan Arshad

Electronic Thesis and Dissertation Repository

Current efforts in the tissue engineering field are being directed towards the creation of platforms which will facilitate in instructing cells towards biologically relevant outcomes such as stem cell differentiation and disease pathophysiology. Traditional fabrication methods serve as a limiting factor for the production of such platforms as they lack feature and geometric complexity. Additive Manufacturing (AM) offers advantage over said methods by affording designers creative freedom and great control over printed constructs. Such constructs can then be used to create appropriate models for study- ing a plethora of tissues and structures. An AM methodology for Direct-Ink Write (DIW) printing …

Left Atrial Model, Borna Sobati, Sarah Porello, Tess Pate

Biomedical Engineering

The objective is to produce an electrophysiological model of an adult human left atrium. This model will be used to test mapping probe catheters used for locating cardiac arrhythmias against current technology used in practice. Dr. Chris Porterfield requested this model and other physicians or probe catheter manufacturers may also use this product in the future. Dr. Porterfield also discussed the possibility of future senior project groups using the model as a bench test for designing new catheter tips. The model will precisely simulate electrical behaviors of the heart in normal as well as arrhythmic conditions. Ideally, the model will …

“Polysoaps” Via Raft Copolymerization To Form Well-Defined Micelles For Water Remediation And Targeted Drug Delivery Applications, Phillip Pickett

Dissertations

Amphiphilic copolymers have become increasingly important for environmental and biological applications due to their behavioral characteristics in aqueous solution. For example, structurally-tailored statistical amphiphilic copolymers or “polysoaps” can self-assemble into micelles or other architectures in water at various concentrations. Polysoaps may be differentiated from small molecule surfactant micelles in their capability to self-assemble into unimolecular associates (unimolecular micelles) with no dependence on concentration. Such micelles offer enormous potential for dispersion of hydrophobic species in water at high dilution. Importantly, each polymer chain forms its own micelle and upon dilution, these micelles remain intact and capable of dispersing hydrocarbon material in …

Engineering Multifunctional And Morphologically Diverse Polymer Brush Surfaces, Cassandra M. Reese

Dissertations

The combination of surface-initiated polymerization (SIP) and post-polymerization (PPM) serves as a powerful approach to fabricate complex, multifunctional polymer films, which can be precisely tuned for desired surface engineering applications. Careful manipulation of PPM parameters such as reaction conditions, the tethered brush parameters, and the physical properties of the unbound post-modifier greatly influence the depth of penetration of the post-modifier and the polymer brush compositional heterogeneity. This dissertation focuses on engineering polymer brush surfaces with multifunctional chemistries and tunable morphologies by investigating the PPM parameters that dictate the distribution of post-modifiers on grafted polymer brush surfaces.

The first chapter of …

Investigation Of Critical Technologies Of Chemical Vapor Deposition For Advanced (Si)Gesn Materials, Joshua Matthew Grant

Graduate Theses and Dissertations

The development of new materials for efficient optoelectronic devices from Group IV elements is the heart of Group IV photonics. This has direct ties to modern technology as the foundation for the electronics industry is silicon. This has driven the development of silicon-based optoelectronics using these other Group IV materials as silicon is a poor optical material due to its indirect band gap when compared to the III-V semiconductors that are used by most of the optoelectronics industry. While efforts have been made to integrate III-V materials onto silicon substrates, the incompatibility with the complementary metal oxide semiconductor process has …

Development Of A Multi-Probe Kelvin Scanner Device For Industrially-Relevant Characterization Of Surface-Activated Carbon Fiber Reinforced Thermoplastic Composites, Kirby Simon

McKelvey School of Engineering Theses & Dissertations

Carbon fiber reinforced thermoplastic (CFRTP) composites are becoming increasingly attractive materials in manufacturing due to their lightweight nature, mechanical strength, and corrosion resistance. Surface activation of these materials is usually required during processing to increase the bond strength of assemblies (aerospace and automotive industries) or improve adhesion with implants (biomedical industry). Industrially-relevant, nondestructive quality control methods for assessing the activation state of these materials do not currently exist, however. Applying principles discovered through the use of scanning probe microscopy, a multiple-probe Kelvin scanning (MPKS) device has been developed that can assess the uniformity of the activation state of plasma-treated CFRTP …

Influence Of Mechanical Properties Of Paper Coating On The Crack At The Fold Problem, Seyyed Mohammad Hashemi Najafi

Electronic Theses and Dissertations

Paper coating layers are subject to various stresses and deformations in many converting processes such as calendering, printing, slitting, and folding of the paper. In some cases, products may crack during folding to generate a defect called cracking at the fold (CAF). The parameters that influence these defects are not well understood. The overall goal of this thesis is to better understand the CAF behavior as related to material properties of the coating layer.

A method was developed to produce free-standing pigmented coating layers thick enough to be tested in bending as well as tension. The mechanical properties of these …

Research Of Electro-Optical Effect In Metal Halide Perovskites By Fabry-Perot Interometer Method, Hanxiang Yin

McKelvey School of Engineering Theses & Dissertations

Perovskites have been investigated a lot by present and reported with outstanding optoelectronic properties. However, so far there is no publications about another important property, the electro-optical (EO) effect which is related to important applications in photolithography. This thesis is mainly mean to calculate the EO constants of one kind of organic perovskite material, CH₃NH₃PbI₃, which has been reported to have good capability of forming film by spin-coating, through the way of putting the film of CH₃NH₃PbI₃ between two layers of metal mirrors to build a Fabry-Perot interferometer and …

Silicone Tadpole: Research Into Soft Bodies, Danielle Fernandez

Mechanical Engineering Undergraduate Honors Theses

In this thesis, research is conducted in the area of soft robotics by building a soft tadpole that can deform with a specific air pressure. The goal is to mimic the motion of an organic tadpole in respect to its S-shaped tail movement. The angle of deformation, derived from material mechanic theories, ranges from 45 to 80 degrees for this type of movement. The design includes a head compartment which acts as a tank to transfer nitrogen pressure and a tail section that receives the said pressure and bends as a result. The tail section was designed with two rows …

Improved Data Acquisition Using A Novel Dynamic Mechanical Analysis Sample Preparation Technique: The Numbers Do Not Lie, Jordan J. Winetrout

Honors Theses

Dynamic mechanical analysis (DMA) is a technique commonly used to identify the thermomechanical properties of polymeric materials. In the aerospace industry, a typical DMA sample is a glassy epoxy-amine polymer network. On a laboratory scale, these types of materials are cured in a silicon mold and sanded by hand to yield a sample with testable dimensions. This preparation technique is time consuming and causes sample imperfections which negatively affects data acquisition. This thesis aims to absolve the issues with DMA sample preparation by using a custom vacuum housing and a DeWALT^TM brand orbital sander. This novel approach has been …

Design Process Of A Novel Dynamic Mechanical Analysis Sample Preparation Methodology, Julian M. Richardson

Honors Theses

The technique of dynamic mechanical analysis (DMA) has been a frontrunner in the field of polymer science for decades. It’s used as a tool for characterization has been integral in mankind’s understanding of the properties of polymeric materials. The procedure for obtaining data using DMA is widespread and standardized, however the procedure for preparing the samples is a list of dimensions and tolerances with no mention of how to obtain said dimensions. Every research group using DMA is left to their own devices to prepare samples. This discontinuity can create the problem of nonuniform results across the scientific community. This …

A New Pedot Synthesis Method And Its Application In Energy Storage, Haozhe Chen

McKelvey School of Engineering Theses & Dissertations

Conducting polymer is a common electrode material in supercapacitors, people usually create nano-structure on electrode surface to enhance the performance of supercapacitors. Synthetic nanostructured polymers have been implemented in many ways, most of them are template-based synthesis, which is time consuming and expensive, people are pursuing an easier way to synthesize nanostructured conducting polymers. Combining ferric chloride solution hydrolysis and EDOT polymerization to get PEDOT nano fiber in one step has been achieved. We develop a new method to synthesis PEDOT nano fiber from solid-state iron in one step. Our process takes place in a single step inside a sealed …