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Articles 1 - 30 of 127
Full-Text Articles in Mechanical Engineering
A Novel Magnetorheological Pump Concept For Insulin Delivery, Mohammad Towhidul Islam Rimon
A Novel Magnetorheological Pump Concept For Insulin Delivery, Mohammad Towhidul Islam Rimon
Electronic Theses and Dissertations
Over the past 25 years, awareness of type 1 diabetes has significantly increased, leading to a comprehensive understanding of various aspects, including its genetics, epidemiology, and disease burden. According to the Type 1 Diabetic Index, about 8.7 million people around the world live with this long-term autoimmune disease characterized by insulin deficiency and resultant hyperglycemia. However, the increased availability and utilization of artificial pancreas systems could potentially save 673,000 lives by 2040. Although, the advancement of diabetes technology offers Type 1 diabetic patients more tools to enhance glycemic management and achieve effective outcomes, many patients are still hesitant to adopt …
Graphene Reinforced Polymer Composite For Small-Scale Vertical Axis Wind Turbine Rotors, Kunal A. Bachim
Graphene Reinforced Polymer Composite For Small-Scale Vertical Axis Wind Turbine Rotors, Kunal A. Bachim
Mechanical and Aerospace Engineering Theses
Polymers have evolved as an indispensable asset in various sectors ranging from packaging and construction to energy and aerospace. However, the accumulation of polymer waste poses a necessity to shift toward sustainable waste management processes. Mechanical recycling is a primary method in establishing a circular economy approach for polymers. However, a fundamental challenge arises in this process: a decrease in the mechanical performance of the recycled product compared to that of its pristine counterpart.
This project addresses the challenge of enhancing the recyclability of polyethylene terephthalate (PET) from discarded polymer material by incorporating graphene nanoparticles into the polymer matrix during …
Modeling Of Asphalt Concrete For Cross-Anisotropic Visco-Elasticity And Heterogeneity, Zafrul Hakim Khan
Modeling Of Asphalt Concrete For Cross-Anisotropic Visco-Elasticity And Heterogeneity, Zafrul Hakim Khan
Civil Engineering ETDs
Asphalt Concrete (AC) is a cross-anisotropic viscoelastic material. This study has developed a methodology to backcalculate the cross-anisotropic properties of the AC layer from the Falling Weight Deflectometer (FWD) sensor and pavement response data from embedded sensors inside a pavement section. This study has also developed a two-way coupled Multiscale Finite Element Model (MsFEM) with Phase Field Fracture (PFF) to study the microstructural heterogeneity and damage of the AC layer based on the actual field loadings. A Finite Difference Time Domain (FDTD) and Machine learning-based backcalculation algorithm were developed to determine the layer thickness and dielectric constant from air-coupled Ground …
Design, Fabrication And Characterization Of Zero Power Sensor/Harvester For Smart Grid Applications, Zeynel Guler
Design, Fabrication And Characterization Of Zero Power Sensor/Harvester For Smart Grid Applications, Zeynel Guler
Mechanical Engineering ETDs
This study presents a flexible sensor/harvester device to be used in both electromagnetic sensing and energy harvesting applications for smart grids. When a current passes through a wire, the sensor detects the magnetic field created by that current. The sensor magnet interacts with the wire magnetic field resulting in a transfer of energy through the piezoelectric cantilever. Piezoelectric, conductive, magnetic, and magnetostrictive composite thin films were prepared to fabricate this device.
Initially, the magnet of the cantilever was optimized considering its shape, thickness, length, taper angle etc. via both simulations and experiments. Peak to peak voltage versus cantilever position graph …
Cfrp Delamination Density Propagation Analysis By Magnetostriction Theory, Brandon Eugene Williams
Cfrp Delamination Density Propagation Analysis By Magnetostriction Theory, Brandon Eugene Williams
All Dissertations
While Carbon Fiber Reinforced Polymers (CFRPs) have exceptional mechanical properties concerning their overall weight, their failure profile in demanding high-stress environments raises reliability concerns in structural applications. Two crucial limiting factors in CFRP reliability are low-strain material degradation and low fracture toughness. Due to CFRP’s low strain degradation characteristics, a wide variety of interlaminar damage can be sustained without any appreciable change to the physical structure itself. This damage suffered by the energy transfer from high- stress levels appears in the form of microporosity, crazes, microcracks, and delamination in the matrix material before any severe laminate damage is observed. This …
Analyzing The Effects Of Ultrafast Laser Processing On Mechanical Properties Of 3d-Printed Pla Parts, Darshan Pramodbhai Yadav
Analyzing The Effects Of Ultrafast Laser Processing On Mechanical Properties Of 3d-Printed Pla Parts, Darshan Pramodbhai Yadav
Theses and Dissertations
Recent advances in additive manufacturing technologies have already led to wide-scale adoption of 3D-printed parts in various industries. The expansion in choice of materials that can be processed, particularly using Fused Deposition Modeling (FDM), and the steady advancements in dimensional accuracy control have extended the range of applications far beyond rapid prototyping. However, additive manufacturing still has considerable limitations compared to traditional and subtractive manufacturing processes. This work addresses limitations associated with the as-deposited surface roughness of 3D-printed parts. The effects of roughness-induced stress concentrations were studied on ultimate tensile strength and fatigue life. The samples were manufactured using a …
Modular Composite Sandwich Structures For Thermal And Structural Retrofitting Of Existing Buildings, Marc Al Ghazal
Modular Composite Sandwich Structures For Thermal And Structural Retrofitting Of Existing Buildings, Marc Al Ghazal
Masters Theses
Around 40% of global energy consumption and 30% of worldwide carbon dioxide (CO2) emissions are attributed to buildings. Most of this consumption is dedicated to ensuring thermal comfort. The goal of this research was to develop and field validate retrofit solutions to improve the energy efficiency of buildings. Exterior cladding panels were designed and tested to ensure adequate thermal and structural performance. Sandwich panels (glass fibers reinforced polymer (GFRP) skins and polymeric foam cores) were fabricated using the vacuum assisted resin transfer molding (VARTM) process. Extruded polystyrene (XPS) and polyurethane (PU) foams were compared as core materials through a series …
Investigating The Effect Of Bead Geometry On Fiber Orientation And Thermomechanical Properties For Large-Format Extrusion-Based Additive Manufacturing, Joanna F. Keaton
Investigating The Effect Of Bead Geometry On Fiber Orientation And Thermomechanical Properties For Large-Format Extrusion-Based Additive Manufacturing, Joanna F. Keaton
Electronic Theses and Dissertations
In large-format extrusion-based additive manufacturing of polymer composites, the relationship between material properties and processing parameters requires further investigation. This thesis focuses on the relationship between fiber orientation and thermomechanical properties for short fiber-filled thermoplastic polymer systems manufactured by extrusion-based additive manufacturing. Fiber orientation is particularly important in determining the thermomechanical properties of the composite material as properties in the direction of deposition are expected to be higher for highly aligned fibers than randomly aligned fibers. Fiber orientation distribution, which is related to processing parameters and deposition conditions, can be efficiently represented by the orientation tensor. The orientation tensor can …
Mechanical Characterization Of Automated Fiber Placement And Additive Manufacturing Hybrid Composites, Lucan Haviland
Mechanical Characterization Of Automated Fiber Placement And Additive Manufacturing Hybrid Composites, Lucan Haviland
Electronic Theses and Dissertations
This thesis presents the optimization of processing parameters based on the mechanical properties of Continuous Fiber-Reinforced Thermoplastic (CFRTP) Unidirectional (UD) consolidated tapes. The UD tapes were consolidated using an AFP head and a thermoforming press for comparison. The adhesive strength of hybrid parts consisting of CFRTP UD tape bonded to a 3D-printed substrate with the same matrix system were investigated. Large Area Additive Manufacturing (LAAM) was utilized for the 3D-printed parts. Different types of thermoplastic composite materials were explored, including Glass Fiber reinforced Polyethylene Terephthalate Glycol (GF/PETG), Carbon Fiber reinforced Polyethylene Terephthalate Glycol (CF/PETG), Carbon Fiber reinforced Polycarbonate (CF/PC), and …
Numerical Modeling And Simulation On Deformation And Failure Behaviors Of Polymeric Materials, Heng Feng
Numerical Modeling And Simulation On Deformation And Failure Behaviors Of Polymeric Materials, Heng Feng
Electronic Thesis and Dissertation Repository
Featured by biocompatibility, high compliance and capacity in sustaining large deformation, dielectric elastomers (DEs) and hydrogels have gained extensive research popularity for their potential applications in the fields of soft robots, biomimetics, tissue engineering, drug delivery, and energy harvesting. The design of such soft and smart material-based devices and structures requires deep understanding and accurate simulation of their constitutive behaviors, which is challenged by their nonlinear material properties due to unique microstructures and multi-physics coupling. Meanwhile, in different application contexts, those structures are also susceptible to different failure modes, imposing further challenges in simulating and predicting their performance. To fulfill …
Double Cantilever Beam Mode-I Testing Validation In Large-Scale Additive Manufacturing Carbon Composite, Luis Alfonso Camacho
Double Cantilever Beam Mode-I Testing Validation In Large-Scale Additive Manufacturing Carbon Composite, Luis Alfonso Camacho
Open Access Theses & Dissertations
Testing for mechanical properties for additive manufacturing has been based on already existing standards for traditional manufacturing methods. For composites in large scale additive manufacturing there is a research gap in bond strength and fracture toughness for a single layer interface. By using Double cantilever beam Mode I, this thesis manuscript validates testing parameters and protocols to describe the intricacies of ABS matrix 20 wt.% carbon filled composite, specifically on the layer-to-layer interface. Studies suggest that fracture toughness is sensitive to process parameters, like deflection speed and sharpened crack tip at the layer interface of BAAM 3D printed part and …
Life Cycle Energy Assesment Of Advanced Fiber Reinforced Composite Design And Manufacturing Methodologies, Urjit Lad
All Theses
Automotive industry at large is focused on vehicle light-weighting since a 6%-8% increase in fuel efficiency can be achieved with a 10% reduction in vehicle weight [1]. With the growing demand for cost-effective and sustainable light weighting of automobile structures, interest has increased in the application of fiber reinforced plastic (FRP) composites for use in the Body-in-White (BiW), which can account for up to 40% of the total vehicle weight. Traditional FRP composite manufacturing processes like vacuum assisted resin transfer molding, autoclave consolidation or use of automated fiber placement have been successfully used for marine and aerospace applications. However, these …
Characterization Of Mechanically Recycled Polylactic Acid (Pla) Filament For 3d-Printing By Evaluating Mechanical, Thermal, And Chemical Properties And Process Performance, Mahsa Shabani Samghabady
Characterization Of Mechanically Recycled Polylactic Acid (Pla) Filament For 3d-Printing By Evaluating Mechanical, Thermal, And Chemical Properties And Process Performance, Mahsa Shabani Samghabady
All Theses
Polylactic acid (PLA) is a biopolymer made from renewable resources such as sugar and corn. PLA filament is a popular material used in Fused Deposition Modeling (FDM) 3D-printing. While this material has many advantages, all the failed parts, support structures, rafts, nozzle tests, and the many prototype iterations during the 3D-printing process contribute to the plastic pollution and release of greenhouse gases. Although PLA is biodegradable, it can take years to degrade in landfills. Instead of throwing away PLA waste and buying new filaments, PLA can be recycled. Amongst the different recycling technologies, mechanical recycling is the most environmentally friendly. …
Comparative Analysis On Low Cost Continuous Carbon Fiber Polypropylene Composite Using Compression Molding And Automated Tape Placement, Benjamin U. Schwartz
Comparative Analysis On Low Cost Continuous Carbon Fiber Polypropylene Composite Using Compression Molding And Automated Tape Placement, Benjamin U. Schwartz
Masters Theses
Carbon fiber reinforced plastics (CFRP) are widely used throughout the aerospace industry where a weight reduction remains the highest priority with less emphasis on cost. Textile grade carbon fiber (TCF) and other low cost carbon fiber (LCCF) alternatives have recently emerged for use in the automotive market where emissions regulations have pushed automotive manufacturers and research institutions to look for cost effective light weight materials. Fiber reinforced thermoplastics provide an effective solution that align with automotive design including low cost, high processing rates, high impact toughness, unlimited shelf life, and recyclability.
TCF and Zoltek_PX35 fibers are two LCCF aimed at …
Shape Memory Polymer-Based Multifunctional Syntactic Foams, Siavash Sarrafan
Shape Memory Polymer-Based Multifunctional Syntactic Foams, Siavash Sarrafan
LSU Doctoral Dissertations
With the increase in popularity of shape memory polymers (SMPs), especially in applications such as aerospace, textile, biomedical engineering, and even structures, the weight of the material and the devices made with it has always been a crucial factor. Using the shape memory polymer as a matrix to make a syntactic foam is one of the best and most affordable approaches to creating a lighter material that still has the shape memory effect. The addition of particles of different stiffness, strength, and size, with variable fractions, creates a composite that enables engineering the mechanical, as well as other physical and …
Controlling Mechanical Properties Of Well-Defined Polymer Networks, Ipek Sacligil
Controlling Mechanical Properties Of Well-Defined Polymer Networks, Ipek Sacligil
Doctoral Dissertations
Polymer networks are one of the most versatile and highly studied material class that revolutionized many aspects of life. Connecting the final network properties to the molecular parameters of its building blocks remains a major research thrust. Recent advances in network synthesis techniques allowed for accurate predictions of elastic modulus in model networks. Tew Group has developed highly efficient, thiol-norbornene networks with controllable mechanical properties. Chapter 2 focuses on modifying the gel fracture energy predicted by Lake-Thomas theory by accounting for loop defects. This study allowed for a priori estimates of gel fracture energy by combining theory, experiments, and simulations. …
Additive Manufacturing For Phase Change Thermal Energy Storage And Management, Thomas B. Freeman
Additive Manufacturing For Phase Change Thermal Energy Storage And Management, Thomas B. Freeman
Doctoral Dissertations and Master's Theses
Phase change materials can enhance the performance of energy systems by time shifting or reducing peak thermal loads. Certain electronic devices such as batteries, laser systems, or electric vehicle power electronics are highly transient and require pulse heat dissipation. Heat sinks, or thermal management devices made of a phase change material can absorb large heat spikes while maintaining a constant temperature. Additive manufacturing techniques hold tremendous potential to enable co-optimization of material properties and device geometry, while potentially reducing material waste and manufacturing time. Recently, a few efforts have emerged that employ additive manufacturing techniques to integrate a phase change …
Molecular Dynamics Modeling Of Polymers For Aerospace Composites, Swapnil Sambhaji Bamane
Molecular Dynamics Modeling Of Polymers For Aerospace Composites, Swapnil Sambhaji Bamane
Dissertations, Master's Theses and Master's Reports
Polymer matrix composite materials are widely used as structural materials in aerospace and aeronautical vehicles. Resin/reinforcement wetting and the effect of polymerization on the thermo-mechanical properties of the resin are key parameters in the manufacturing of aerospace composite materials. Determining the contact angle between combinations of liquid resin and reinforcement surfaces is a common method for quantifying wettability. It is challenging to determine contact angle values experimentally of high-performance resins on CNT materials such as CNT, graphene, bundles or yarns, and BNNT surfaces. It is also experimentally difficult to determine the effect of polymerization reaction on material properties of a …
Study Of Nanocomposite Materials Using Molecular Dynamics, Prashik Sunil Gaikwad
Study Of Nanocomposite Materials Using Molecular Dynamics, Prashik Sunil Gaikwad
Dissertations, Master's Theses and Master's Reports
There is an increase in demand for new lightweight structural materials in the aerospace industry for more efficient and affordable human space travel. Polymer matrix composites (PMCs) with reinforcement material as carbon nanotubes (CNTs) have shown exceptional increase in the mechanical properties. Flattened carbon nanotubes (flCNTs) are a primary component of many carbon nanotube (CNT) yarn and sheet materials, which are promising reinforcements for the next generation of ultra-strong composites for aerospace applications. These flCNT/polymer materials are subjected to extreme pressure and temperature during curing process. Therefore there is a need to investigate the evolution of properties during the curing …
An Experimental Study On The Mechanical Properties And Chemical Composition Of Lcd 3d Printed Specimens, Sebastian Gomez
An Experimental Study On The Mechanical Properties And Chemical Composition Of Lcd 3d Printed Specimens, Sebastian Gomez
Electronic Theses and Dissertations
Additive manufacturing technologies have been enhanced throughout the years yet have surprised the manufacturing industry due to their high-end surface finish and dimensional accuracy. Different experiments have been done to identify a specific phenomenon known in the vat-polymerization field. Distortion and dimensional inaccuracy tend to affect the overall properties of the process, either physical or chemical. This approach allows the understanding of how the physical properties have been affected and how to study the chemical properties to avoid this type of phenomenon. The chemical reaction between polymer and UV light has been studied and experimented with to the point that …
Optimized 3d-Printing Of Carbon Fiber-Reinforced Polyether-Ether-Ketone (Cfr-Peek) For Use In Overmolded Lattice Composite, Ryan C. Ogle
Optimized 3d-Printing Of Carbon Fiber-Reinforced Polyether-Ether-Ketone (Cfr-Peek) For Use In Overmolded Lattice Composite, Ryan C. Ogle
Masters Theses
Current orthopedic implants are overwhelmingly composed from metallic materials. These implants show superior mechanical properties, but this can additionally result in stress shielding due to a modulus mismatch between the bone tissue and implanted device. Polymeric implants reduce this stress shielding effect but have much lower mechanical properties, limiting their use. Polylactic acid (PLA) is a widely used biodegradable thermoplastic polymer, however, its use has been limited by the polymer’s mechanical properties and rapid loss of strength during degradation in vivo. Polyether-ether-ketone (PEEK) is another common biocompatible polymer , with chemical and mechanical properties which make it a popular alternative …
A Machine Learning Approach To Robotic Additive Manufacturing Of Uv-Curable Polymers Using Direct Ink Writing, Luis A. Velazquez
A Machine Learning Approach To Robotic Additive Manufacturing Of Uv-Curable Polymers Using Direct Ink Writing, Luis A. Velazquez
LSU Master's Theses
This thesis presents the design and implementation of a robotic additive manufacturing system that uses ultraviolet (UV)-curable thermoset polymers. Its design considers future applications involving free-standing 3D printing by means of partial UV curing and the fabrication of samples that are reinforced with fillers or fibers to manufacture complex-shape objects.
The proposed setup integrates a custom-built extruder with a UR5e collaborative manipulator. The capabilities of the system were demonstrated using Anycubic resin formulations containing fumed silica (FS) at varying weight fractions from 2.8 to 8 wt%. To fully cure the specimens after fabrication, a UV chamber was used. Then, measurements …
Numerical Modeling Of Localized Heating In Continuous Fiber Reinforced Thermoplastic Laminates, James T. Gayton
Numerical Modeling Of Localized Heating In Continuous Fiber Reinforced Thermoplastic Laminates, James T. Gayton
Electronic Theses and Dissertations
The manufacturing of continuous fiber-reinforced thermoplastic (CFRTP) laminates requires the application of heat and pressure. Standard CFRTP manufacturing methods like thermoforming take a global approach to manufacturing, where the whole part is heated and undergoes a forming process. There is an opportunity to develop advanced manufacturing methods based on localized heating and deformations of consolidated stock. This thesis provides a localized heating method via networks of resistive heating elements embedded within the laminate and a means to evaluate that method.
Typical heating methods for CFRTP laminates include infrared and convective ovens or surface contact heaters. They have the same drawbacks …
Predictive Thermal Modeling And Characterization Of Ultrasonic Consolidation Process For Thermoplastic Composites, Madeline Kirby
Predictive Thermal Modeling And Characterization Of Ultrasonic Consolidation Process For Thermoplastic Composites, Madeline Kirby
LSU Master's Theses
Ultrasonic consolidation (USC) of thermoplastic composites (TPCs) is a highly attractive and promising method to manufacture high-performance composites. This work focuses on USC of dry carbon fiber (CF) fabrics with high-temperature polyphenylene sulfide (PPS) films. Experimental trials to assess feasibility of the process are time-consuming. Consequently, a predictive thermal model would facilitate process parameters selection to reduce expensive trial-and-error approaches. This paper presents a 2D finite element model of samples under consolidation, incorporating equations for viscoelastic heating, matrix phase change, and material properties. Theoretical temperature profiles for nodes of interest were compared to the corresponding experimental temperature curves for various …
Evaluating The Effects Of Granulated Rubber And Glass Fibers In Polymer Concrete As A Structural Material For Wafer Grinding Machines, Kevin Gabriel Kuehn, Philip Randall Streeter
Evaluating The Effects Of Granulated Rubber And Glass Fibers In Polymer Concrete As A Structural Material For Wafer Grinding Machines, Kevin Gabriel Kuehn, Philip Randall Streeter
Materials Engineering
Polymer concrete is a composite material used to replace cast iron and steel in wafer grinding machines for vibration damping. During the grinding and lapping processes of manufacturing silicon wafers, excessive vibrations may cause subsurface damage which requires additional polishing and reduces yield. Nine compositions containing various levels of granulated rubber and glass fibers were manufactured. CRM WRF-10 granulated rubber was examined at 0%, 5%, and 10% and Corning Cem-Fil glass fibers were added at 0%, 0.5%, and 1% by weight. Smooth-On EpoxAcast 690 epoxy resin was held constant at 16% for each composition. Crushed granite aggregate from Martin Marietta, …
Development And Evaluation Of Modeling Approaches For Extrusion-Based Additive Manufacturing Of Thermoplastics, Christopher C. Bock
Development And Evaluation Of Modeling Approaches For Extrusion-Based Additive Manufacturing Of Thermoplastics, Christopher C. Bock
Electronic Theses and Dissertations
This work focuses on evaluating different modeling approaches and model parameters for thermoplastic AM, with the goal of informing more efficient and effective modeling approaches. First, different modeling approaches were tested and compared to experiments. From this it was found that all three of the modeling approaches provide comparable results and provide similar results to experiments. Then one of the modeling approaches was tested on large scale geometries, and it was found that the model results matched experiments closely. Then the effect of different material properties was evaluated, this was done by performing a fractional factorial design of experiments where …
Electromechanical Fatigue Properties Of Dielectric Elastomer Stretch Sensors Under Orthopaedic Loading Conditions, Andrea Karen Persons
Electromechanical Fatigue Properties Of Dielectric Elastomer Stretch Sensors Under Orthopaedic Loading Conditions, Andrea Karen Persons
Theses and Dissertations
Fatigue testing of stretch sensors often focuses on high amplitude, low-cycle fatigue (LCF) behavior; however, when used for orthopaedic, athletic, or ergonomic assessments, stretch sensors are subjected to low amplitude, high-cycle fatigue (HCF) conditions. As an added layer of complexity, the fatigue testing of stretch sensors is not only focused on the life of the material comprising the sensor, but also on the reliability of the signal produced during the extension and relaxation of the sensor. Research into the development of a smart sock that can be used to measure the range of motion (ROM) of the ankle joint during …
Additive Manufacturing Of Variable Contrast Computed Tomography Anatomical Phantoms Using A Single Feedstock In Fused Filament Fabrication, Cory J. Darling
Additive Manufacturing Of Variable Contrast Computed Tomography Anatomical Phantoms Using A Single Feedstock In Fused Filament Fabrication, Cory J. Darling
University of New Orleans Theses and Dissertations
Anatomical phantoms used in biomedical education and training benefit greatly from Fused filament fabrication’s (FFF) ability to rapidly produce complex and unique models. Current materials and methods used in FFF have limited ability to accurately produce phantoms that can mimic the radiological properties of multiple biological tissues. This research demonstrates that the CT contrast of FFF produced models can be modified by varying the concentration of bismuth oxide in acrylonitrile butadiene styrene (ABS) filaments and a tunable CT contrast that mimics the CT contrast ranging from fatty tissue to cortical bone using a single composite filament without introducing artificial image …
Effects Of Sizing Agents On Mechanical Properties Of Carbon Fiber–Polymer Composites Via Fused Filament Fabrication Additive Manufacturing., Benjamin D. Mitchell
Effects Of Sizing Agents On Mechanical Properties Of Carbon Fiber–Polymer Composites Via Fused Filament Fabrication Additive Manufacturing., Benjamin D. Mitchell
Electronic Theses and Dissertations
This study demonstrated the effects of changing the sizing agent parameter during the preparation of carbon fibers on the mechanical properties of composite made with acrylonitrile butadiene styrene (ABS) as the matrix material and carbon fibers as the fiber material. Three types of sizing agents produced by Allnex were used to coat three different batches of carbon fibers that were mixed with a torque rheometer and extruded with a barrel-style melt extruder into continuous spools of 1.75 mm filament for use with commercial 3D printers. Tensile tests were conducted on the filaments and tensile bars printed from the materials. Results …
Synthesis, Fabrication, And Assembly Of Mesoscale Polymer Filaments, Dylan M. Barber
Synthesis, Fabrication, And Assembly Of Mesoscale Polymer Filaments, Dylan M. Barber
Doctoral Dissertations
Mesoscale materials, with feature sizes in the range of one hundred nanometers to tens of micrometers, are ubiquitous in Nature. In organisms, mesoscale building blocks connect the properties of underlying molecular and nanoscructures to those of macroscale, organism-scale materials through hierarchical assemblies of recurring structural motifs. The collective action of large numbers of mesoscale features can afford stunning features like the structural color of the morpho butterfly wing, calcium ion-mediated movement in muscle, and wood structures like xylem that can support enormous external compressive loads and negative internal pressure to transport nutrients throughout an organism. In synthetic systems, the design, …