Engineering Commons^™

Well-Ordered Nanohybrids And Nanoporous Materials From Block Copolymer Templates, Rong Ho

Composites at Lake Louise (CALL 2015)

The design of nanostructured materials and their corresponding morphologies has attracted intense attention. Although many technologies have been explored to fabricate nanostructured materials, templated synthesis is one of the most important approaches to fabricate nanostructured materials with precisely controlled structures and morphologies from their constituent components. Here, we aim to use the self-assembly of block copolymers as an emerging and powerful tool to fabricate well-defined nanomaterials with precise control over the structural dimensions and shape, as well as over the composition and corresponding spatial arrangement. The fabrication of well-ordered nanoporous polymers from the self-assembly of degradable block copolymers, in particular …

Thermosetting Polymers And Composites From Agricultural Oils, Michael Kessler, Richard Larock

Composites at Lake Louise (CALL 2015)

Renewable, bio-based thermosetting copolymer resins, ranging from tough and ductile rubbers to hard and glassy plastics to durable waterborne latex coatings, have been prepared by the polymerization of soybean, corn and linseed oils with various co-monomers. The development of these resin formulations with the right combination of processing viscosity, cure kinetics, and ultimate thermal mechanical properties for various manufacturing processes will be discussed. As expected, the thermal and mechanical properties, as well as the long term environmental durability of the material, are shown to be highly dependent on vegetable-oil composition, processing conditions, and co-monomer chemistry. These new bioplastic composites are …

Rare Earths, Rare-Earth Oxides, And The Ocides’ Unique Character: Application For Environmental Catalysts, Nobuhito Imanaka

Composites at Lake Louise (CALL 2015)

The rare earths series will be comprehensively introduced. The difference among lanthanide, lanthanoid, and rare earths will be also clearly defined. After these lectures, the unique characteristics of rare-earth oxides will be addressed. As one of promising applications of the rare earth oxides, the oxides’ unique character of oxide anion migration in the solids will be also introduced and also for the application as the environmental catalysts.

Here, we focused on C-type cubic Gd₂O₃, and Y₂O₃ which has relatively strong basicity among rare earth elements, as a fundamental oxide to develop a novel …

Nanostructured Metal-Ceramic Composites By Internal Reduction, Ivar Reimanis, Amy Morrissey

Composites at Lake Louise (CALL 2015)

The nucleation and growth of metallic particles within metal-doped oxides exposed to reducing conditions is relevant to the processing of materials for catalysts, fuel cells, and structural applications. Here, the precipitation of metallic nickel during the internal reduction of nickel-doped yttria stabilized zirconia (YSZ) is studied with electron microscopy and SQUID magnetometry. It is shown that the microstructure evolution proceeds in three distinct stages, each with its own kinetics description, dependent on the porosity and grain size. The transitions between stages depend on concentration gradients and electrostatic potentials that act upon the relevant transporting species, namely oxygen vacancies, electrons, nickel …

Stimulus-Responsive And Conductive Composites For Remote Sensing Applications, Anastasia Elias, Preetam Anbukarasu, Dominic Sauvageau

Composites at Lake Louise (CALL 2015)

Inexpensive and portable sensors are increasingly democratizing data collection and data analysis on both large and small scales. Materials which are both conducting and responsive (able to undergo a change in property in response to a desired stimulus) could form the basis for a variety of sensors. In our work, we are developing these materials for use in radio frequency identification (RFID) tags in which the conducting and responsive material is integrated directly into the antenna of the tag. A change in the dielectric properties of the antenna leads to a measurable change in the remotely-readable properties of the device, …

Magneto-Ionic Control Of Interfacial Magnetism, Geoffrey Beach

Composites at Lake Louise (CALL 2015)

Voltage control of magnetism has the potential to substantially reduce power consumption in spintronic memory and logic devices, while offering new functionalities through field-effect operation [1-4]. Magneto-electric coupling has most often been achieved using complex oxides such as ferroelectrics, piezoelectrics, or multiferroic materials. Here I describe a new approach to voltage control of magnetism based on solid-state electrochemical switching of the interfacial oxidation state [2-4] in thin metallic ferromagnets. In ultrathin ferromagnet/oxide bilayers, strong perpendicular magnetic anisotropy (PMA) often arises from arises from interfacial hybridization between the ferromagnetic metal and oxygen ions. By using a solid-state ionic conductor with high …

Use Of Capillary Flow To Create Flexible And Embedded Electronics, Lorraine Francis, Ankit Mahajan, Robert Lade, Chris Macosko, Daniel Frisbie

Composites at Lake Louise (CALL 2015)

Continuous printing processes are attractive for manufacturing electronic devices on flexible substrates and embedding electronically functional materials into polymers. In this presentation, a new method to create flexible electronics based on embedded conductive networks is presented. The route involves creating the electronic architecture in a curable polymer layer on a flexible substrate and then using capillary flow to create the conductive network. In this presentation, the method will be discussed with an emphasis on the role of processing. A key process step is liquid ink flow in channels. Liquid flow in open capillary channels depends on the channel geometry and …

Self-Assembly Directs Enamel Formation And Regeneration, Malcolm Snead

Composites at Lake Louise (CALL 2015)

Enamel is a unique bioceramic tissue covering our teeth, which by improving feeding and nutrition fueled an explosion in vertebrate evolution. Enamel is also the tissue affected by the most prevalent infectious disease of humankind, caries. While enamel is the hardest tissue in the vertebrate body it develops as a soft extracellular protein matrix precursor synthesized by ameloblast cells that is composed mainly of the proteins amelogenin and ameloblastin. Amelogenins are small-, hydrophobic-, inherently disordered proteins that self-assembly to form nanospheres through the interaction of two domains located at opposite molecular ends, whereas, ameloblastin self-assembles through but a single N’-terminal …

Stability Of Oxides/Environmental Barrier Coating Candidate Materials In Hightemperature, High-Velocity Steam, Elizabeth Opila, Robert Golden

Composites at Lake Louise (CALL 2015)

Stability of oxides/Environmental Barrier Coating (EBC) candidate materials in high-temperature, high-velocity steam has been characterized using a steam-jet furnace modeled after Lucato et al [1]. The objective of this work is to quantify stability of oxides for use as coatings on SiC-based composites in turbine engine environments with the long term goal of developing thermochemical life prediction models for EBCs. SiO₂, TiO₂, Y₂O₃, and rare earth silicates were exposed in one atmosphere steam flowing at approximately 170 m/s at temperatures between 1200 and 1400°C for times up to 375 h. Oxide recession, …

Automated Fiber Placement Of Multifunctional Fiber-Reinforced Composites, Christopher Hansen, Konstantine Fetfatsidis, Andrew Burke, Bradford Olson

Composites at Lake Louise (CALL 2015)

Multi-functional composite materials, in which additional functions exist beyond the primary structural function, offer broad scope for system-level performance enhancements. Key functions targeted for composite structures include thermal management, self-healing, and structural health monitoring capabilities. Aerospace and other advanced fiber-reinforced composites applications, which will benefit from these capabilities, are increasingly being manufactured via Automated Fiber Placement (AFP); however, the lack of (1) available material systems suitable for AFP and (2) the lack of processing knowledge regarding their deposition and compaction hinder the automated manufacture of these multifunctional features. Here, we present efforts to create functional pre-preg materials suitable for AFP …

Shape Reconfigurable Liquid Metals, Michael Dickey

Composites at Lake Louise (CALL 2015)

Shape often defines the function of materials. Shape reconfigurable materials are those that can change shape (and thus, function) in response to a stimulus. We have been studying new methods to pattern and control the shape of a micromoldable liquid metal and embed it in functional polymers to create conductors that are soft, self-healing, ultra-stretchable, and shape reconfigurable. The metal is a gallium-based metal alloy that is a low-viscosity liquid at room temperature with low toxicity and negligible volatility. Despite the large surface tension of the metal, it can be molded into non-spherical shapes due to the presence of an …

Printing Living Tissues, Jennifer Lewis

Composites at Lake Louise (CALL 2015)

The ability to pattern biomaterials in planar and three-dimensional forms is of critical importance for several applications, including drug safety screening, tissue engineering and repair. 3D printing enables one to rapidly design and fabricate soft materials in arbitrary patterns without the need for expensive tooling, dies, or lithographic masks. In this talk, our efforts to creating vascularized living tissues via 3D bioprinting will be described. I will present recent advances in the design of cell-laden inks, extracellular matrices and fugitive (vascular) inks for 3D bioprinting of vascularized, heterogeneous cell-laden tissue constructs with as well as ongoing efforts to characterize these …

Icosahedral Phase Strengthened Nanocomposites For Structural Components, Thomas Watson

Composites at Lake Louise (CALL 2015)

The discovery of quasicrystals (QCs) in rapidly solidified Al-Mn alloys has led to a fundamental change in the way that we view the structural spectrum from the amorphous to the crystalline state. This also opened up the possibility of a new class of aluminum-based alloys, because the lack of long-range order in QCs precludes the operation of the usual plastic deformation mechanisms. While a significant amount of work has been done in this area with regards to understanding QCs at the atomic level, very little work has been performed on large-scale materials because the desired microstructures tend to require high …

Polymer Melts Inside Nanoscale Cylindrical Pores: Chain Conformations, Polymer Diffusion And Local Dynamics, Karen Winey

Composites at Lake Louise (CALL 2015)

Polymers in composites and inside porous media are frequently confined to spaces that are comparable to or even smaller than their mean end-to-end distances in the unconfined bulk state. Understanding the impact of nanoscale confinement on both polymer structure and dynamics is critical for a variety of applications including hydraulic fracturing fluids, porous inorganic thin films in the electronics industry, and composites. To date, our work focuses on polymer melts under nanoscale cylindrical confinement. The polymer center-of-mass diffusion into cylindrical pores in anodized aluminum oxide membranes (diameters 18 – 80 nm) was measured using elastic recoil detection. This ion beam …

Dispersion Of Powders In Complex Systems, James Adair

Composites at Lake Louise (CALL 2015)

This talk will discuss our colloidal and interfacial as well as materials chemistry approaches for manipulating and dispersing complex material systems. The talk focuses mostly on aqueous dispersion schemes, but the physical chemistry and utility of the ethanol-water system in preparing colloidal suspensions for diagnostic and drug delivery systems for human healthcare will also be presented. Complex material systems covered can include the following topics: fine ceramic multi-component powder dispersion; managing aqueous dispersion with thermodynamically unstable materials via interfacial passivation strategies; and dispersion of nanoscale particulates in simple and complex physiological environments. Many ceramic and metal systems in suspension are …

Cure Kinetics And Interfacial Phenomena In Polymer Matrix Composites, John Kieffer, Michael Aldridge, Katherine Sebeck, Eleanor Coyle

Composites at Lake Louise (CALL 2015)

Polymer matrix composites with textile reinforcement are used in a wide range of aerospace and industrial applications. Continuum mechanical predictions of the composite behaviors have been inaccurate, possibly because of the lack of information with regard to polymer materials properties, especially near the interfaces with the reinforcing fibers. Concurrent micro-Brillouin and Raman light scattering provides sufficiently high spatial resolution to probe the mechanical properties and chemical composition of the interphase regions of the matrix, without interfering with the thermo-mechanical equilibrium of the material. Using this technique, we mapped the elastic properties of epoxy resin in between and within the fiber …

Additive Manufacturing Of Bulk Refractory Fiber Within The Ta-Hf-C System For Ultra High-Temperature Reinforced Composite Materials, James Maxwell, Ryan Hooper, Nicholas Webb, Jimmy Allen

Composites at Lake Louise (CALL 2015)

This work discusses the production of ultra-high temperature material (UHTM) fibers that can be used to reinforce composite materials in extreme environments. Carbon-fiber-based, carbon-matrix composites are commonly used for many UHTM applications; however within an oxygen containing atmosphere, C-C composites are limited by oxidation well-below their ultimate sublimation temperatures. Hence, research is being carried out to create alternative materials, with very high melting points, but that have greater oxidation resistance. SiC-fiber reinforced composites offer one alternative, but are limited to temperatures below 1870K. Of the 12 binary compounds that have melting points above 3270K, Hafnium Carbide (4170K) and tantalum carbide …

Nanoscale Deformation Of Composite Structures And Heterophase Interfaces, Shen Dillon

Composites at Lake Louise (CALL 2015)

Interfaces often govern the properties and performance of composite structures, especially in the context of mechanical response. However, nature of deformation in nanoscale composites and their interfaces requires improved understanding. We have been utilizing in-situ TEM based nanomechanics measurements to isolate individual heterophase interfaces and characterize their properties. Specific applications discussed relate to the role of alloy chemistry in affecting the interfacial strength in nanocomposites and the importance of interfacial deformation in affecting the wear resistance nanoscale tribofilms. The talk will also discuss the important role that nanoscale structural elements play in affecting overall composite properties.

Fabrication And Characterization Of Locally Resonant Acoustic Metamaterials Made With Resonators Generated From Core-Shell Drops, Carlos Martinez, Colton Steiner, C.T. Sun, Jeffrey Youngblood

Composites at Lake Louise (CALL 2015)

Acoustic metamaterials promise the remarkable ability to control, direct, and manipulate sound waves. Within this infant field, a promising approach to fabricate locally resonant acoustic metamaterials is the use of resonators composed of a heavy core surrounded by a rubber shell dispersed in an epoxy matrix. At the resonant frequency, the resonators vibrate 180° out-of-phase with the matrix and a band gap in transmission is observed making these materials excellent sound absorbers. The resonant frequency of the resonators scales with the core mass; therefore, it can be tailored by increasing the core diameter or the density of the core material. …

Reactive Ni-Al Nanostructured Composites Through Electrochemical Dispersion Deposition, Christopher Apblett, Jonathan Coleman, Robert Knepper, Alexander Tappan

Composites at Lake Louise (CALL 2015)

Reactive metal composites (RMC) films are used in various applications from precision joining and brazing to local high heat sources for power generation and local melting. They are gasless, high heat generating, high propagation speed reactions that involve the release of energy when elemental constituents are combined to make intermetallics. These films require solid state diffusion at the nanoscale to function well, and the current method of manufacture is to sputter 20-50nm thick alternating films of the reactant elements to build up a ~50um thick composite film. This process is slow and costly, and does not lend itself well to …

Imaging The Interphase In Polymer Composites, Jeffrey Gilman

Composites at Lake Louise (CALL 2015)

Polymer composites are currently used in aerospace, electronics and recreation. New uses are being explored in infrastructure, light-weight vehicles, and in alternative energy applications, such as solar and wind. Arguably, the most critical feature of a composite is the interface/interphase. The interphase in a polymer composite is the volume of polymer adjacent to the fiber interface, and it can comprise up to 30 % of the polymer when nano-scale additives are used. The interphase controls the effectiveness with which the nanoparticle and polymer interact to produce enhanced properties, but it remains a poorly characterized phase. Characterization of polymer dynamics …

Carbon Nanocomposites Structure And Properties: Insights From Tem Tomography, J. Alexander Liddle

Composites at Lake Louise (CALL 2015)

Despite the exceptional properties of individual carbon nanotubes (CNTs), it has proven difficult to produce composites that demonstrate the hoped-for property enhancements. The gap between expectation and reality can be closed by understanding the difference between the ideal morphology and those currently achievable. As a first step in improving our understanding of these materials, and establishing robust process-structure-property models to aid in their optimization, we have made detailed and accurate measurements of aligned multiwall-CNT/epoxy nanocomposite structure by energy-filtered transmission electron microscope (EFTEM) tomography. These tomographic images, together with novel image processing algorithms, are used to quickly generate accurate reconstructions of …

Design Of Multifunctional Composites And Their Use For The 3-D Printing Of Microsystems, Daniel Therriault

Composites at Lake Louise (CALL 2015)

Many of today's high-tech products are approaching their technological limits. For example, the microelectronics community is faced with overheating devices with a demand for compact three-dimensional (3D) architectures and lower power consumption, whereas the aerospace industry is seeking lighter, stiffer and more electrically conductive materials for the creation of more energy efficient aircraft. A promising solution is to capitalize on the amazing electrical, thermal and mechanical properties of some nanoscopic materials (one billionth of a meter). However, several challenges in material processing and manufacturing must be resolved, namely exploiting these properties at the industrial scale and overcoming the current planar …

Engineering Hydrogels For Dynamic Modulation Of Stem Cell Activity, Kristopher Kilian

Composites at Lake Louise (CALL 2015)

Patient derived mesenchymal stem cells (MSCs) are a promising cell-based autologous therapy for numerous diseases due to the propensity to differentiate to numerous lineages without risk of rejection. Another interesting aspect of the therapeutic potential of these cells is their proven ability to secrete molecules that are immunomodulatory and pro-angiogenic, e.g. living cytokine factories, which may be implanted at a site of injury to promote healing. However, clinical efficacy has proven to be variable, which we postulate is due in part to insufficient control over the injectable biomaterials employed. In our laboratory we have noted a gradual loss of the …

Additively Manufactured Bio-Based Composites, Jennifer Rodriguez, Cheng Zhu, Eric Duoss, Thomas Wilson, Christopher Spadaccini, James Lewicki

Composites at Lake Louise (CALL 2015)

The development of new materials solutions for advanced manufacturing and fabrication technologies is an increasing focus of many research and development efforts in applied materials science today. Advances in these areas are resulting in the development of novel, geometrically complex parts and functional devices in a multitude of arenas, such as the biomedical and aerospace industries. Recent progress in materials research includes; the development of polymer systems that are less reliant on petroleum-based products, and are instead based on renewable, bio-derived sources. Concurrently, new additive manufacturing (AM) technologies are allowing the production of complex parts with structures and physical response …

Layered Biomimetic And Kirigami Nanocomposites, Nicholas Kotov

Composites at Lake Louise (CALL 2015)

Finding materials with combinations of several extreme properties is one of the key requirements for the successful engineering of adaptive systems. Successful realization of such materials requires new choices for nanoscale components and new manufacturing approaches. Layer-by-layer assembly (LBL) is one of such technique that affords engineering of nanocomposite materials based on sequential adsorption of nanometer scale layers of polymers and inorganic particle, nanowires, nanotubes, sheets, etc. Importantly, it can lead to the materials with seemingly “impossible” combinations of physical properties encompassing mechanical, electrical, optical, and biological characteristics and distinct pathways to scalability. Hard-to-reach combinations of electrical and mechanical properties …

Transport Of Nanoparticles In Polyelectrolyte Solutions As A Model Of Polymer Nanocomposite Processing, Jacinta Conrad, Ryan Poling, Firoozeh Babaye, Ramanan Krishnamoorti

Composites at Lake Louise (CALL 2015)

The transport properties of nanoparticles in complex confined media play a significant role in the processing of advanced polymer nanocomposites. In polymer nanocomposite processing, nanoparticles suspended in polymer resins must be efficiently dispersed to obtain optimal mechanical, electrical, thermal, and/or optical properties and eliminate stress concentrators. Here, we investigate the diffusion and dispersion of nanoparticles in solutions of unentangled polyelectrolytes as a model system in which to understand the coupling between particle and polymer dynamics in flow conditions representative of those encountered during nanocomposite processing.

First, we measure the long-time quiescent diffusivity of fluorescent polystyrene nanoparticles in dilute and semidilute …

Aptamer Panning Against Gold, Valeria Milam, Maeling Tapp, Richard Sullivan, Patrick Dennis, Rajesh Naik

Composites at Lake Louise (CALL 2015)

Oligonucleotide aptamers are single-stranded sequences that exhibit high affinity and specificity for a particular non-nucleotide target including, but not limited to small molecules, proteins, and even whole cells. Aptamers are conventionally isolated and identified using a multi-round screening approach called "Systematic Evolution of Ligands by Exponential Enrichment" (SELEX) in which a pool of approximately 10⁹ random candidate sequences is continuously enriched with amplified copies of “winning” sequences or adsorbates from prior selection rounds. While SELEX has revolutionized the discovery of numerous DNA and RNA-based aptamers for a variety of targets and dominated the field for two decades as a …

Click Chemistry And Its Unique Benefits In Composite Formulation, Christopher Bowman, Maciej Podgorski, Chen Wang, Shunsuke Chatani

Composites at Lake Louise (CALL 2015)

Although proposed only 15 years ago, “click” chemistry has already become a powerful tool in many synthetic/preparatic schemes in polymer science. The simplicity and robustness of “click” chemistries render them ideal candidates in engineering composite materials with well-defined physiochemical properties for vast range of applications. Herein we present the advances in the implementation of thiol-X “click” chemistries in various composite materials, exemplified by dental restoration materials, shape memory programmable composites/laminates and latex composite materials. In the first example, we developed a series of thiol-ene monomers in which esters are absent so that they are hydrolytically stable in basic conditions. We …

Scalable Directed Assembly Of Nanostructured Soft Materials, Chinedum Osuji

Composites at Lake Louise (CALL 2015)

Molecular self-assembly of block copolymers and small molecule surfactants gives rise to a rich phase behavior as a function of temperature, composition, and other variables. The ability to precisely control their chemical functionality combined with the readily tunable characteristic length scales (~1-100 nm) of their self-assembled mesophases identifies these systems as a versatile and attractive class of materials for compelling applications ranging from selective transport to lithography. A longstanding problem in this area is the inability to reliably and rapidly generate well-ordered structures with specified orientations in, and over, application-relevant geometries, and dimensions, respectively, i.e. to direct their self-assembly in …