Linda S. Schadler

Bio: Linda S. Schadler is an academic researcher from University of Vermont. The author has contributed to research in topics: Nanocomposite & Polymer nanocomposite. The author has an hindex of 71, co-authored 271 publications receiving 21581 citations. Previous affiliations of Linda S. Schadler include University of Kentucky & University of Pennsylvania.

Load transfer in carbon nanotube epoxy composites

Abstract: The mechanical behavior of multiwalled carbon nanotube/epoxy composites was studied in both tension and compression. It was found that the compression modulus is higher than the tensile modulus, indicating that load transfer to the nanotubes in the composite is much higher in compression. In addition, it was found that the Raman peak position, indicating the strain in the carbon bonds under loading, shifts significantly under compression but not in tension. It is proposed that during load transfer to multiwalled nanotubes, only the outer layers are stressed in tension whereas all the layers respond in compression.

Anisotropic self-assembly of spherical polymer-grafted nanoparticles

Abstract: It is easy to understand the self-assembly of particles with anisotropic shapes or interactions (for example, cobalt nanoparticles or proteins) into highly extended structures. However, there is no experimentally established strategy for creating a range of anisotropic structures from common spherical nanoparticles. We demonstrate that spherical nanoparticles uniformly grafted with macromolecules ('nanoparticle amphiphiles') robustly self-assemble into a variety of anisotropic superstructures when they are dispersed in the corresponding homopolymer matrix. Theory and simulations suggest that this self-assembly reflects a balance between the energy gain when particle cores approach and the entropy of distorting the grafted polymers. The effectively directional nature of the particle interactions is thus a many-body emergent property. Our experiments demonstrate that this approach to nanoparticle self-assembly enables considerable control for the creation of polymer nanocomposites with enhanced mechanical properties. Grafted nanoparticles are thus versatile building blocks for creating tunable and functional particle superstructures with significant practical applications.

Nanocomposite science and technology

Abstract: 1. Bulk Metal and Ceramics Nanocomposites (Pulickel M. Ajayan).1.1 Introduction.1.2 Ceramic/Metal Nanocomposites.1.2.1 Nanocomposites by Mechanical Alloying.1.2.2 Nanocomposites from SolGel Synthesis.1.2.3 Nanocomposites by Thermal Spray Synthesis.1.3 Metal Matrix Nanocomposites.1.4 Bulk Ceramic Nanocomposites for Desired Mechanical Properties.1.5 Thin-Film Nanocomposites: Multilayer and Granular Films.1.6 Nanocomposites for Hard Coatings.1.7 Carbon Nanotube-Based Nanocomposites.1.8 Functional Low-Dimensional Nanocomposites.1.8.1 Encapsulated Composite Nanosystems.1.8.2 Applications of Nanocomposite Wires.1.8.3 Applications of Nanocomposite Particles.1.9 Inorganic Nanocomposites for Optical Applications.1.10 Inorganic Nanocomposites for Electrical Applications.1.11 Nanoporous Structures and Membranes: Other Nanocomposites.1.12 Nanocomposites for Magnetic Applications.1.12.1 Particle-Dispersed Magnetic Nanocomposites.1.12.2 Magnetic Multilayer Nanocomposites.1.12.2.1 Microstructure and Thermal Stability of Layered Magnetic Nanocomposites.1.12.2.2 Media Materials.1.13 Nanocomposite Structures having Miscellaneous Properties.1.14 Concluding Remarks on Metal/Ceramic Nanocomposites.2. Polymer-based and Polymer-filled Nanocomposites (Linda S. Schadler).2.1 Introduction.2.2 Nanoscale Fillers.2.2.1 Nanofiber or Nanotube Fillers.2.2.1.1 Carbon Nanotubes.2.2.1.2 Nanotube Processing.2.2.1.3 Purity.2.2.1.4 Other Nanotubes.2.2.2 Plate-like Nanofillers.2.2.3 Equi-axed Nanoparticle Fillers.2.3 Inorganic FillerPolymer Interfaces.2.4 Processing of Polymer Nanocomposites.2.4.1 Nanotube/Polymer Composites.2.4.2 Layered FillerPolymer Composite Processing.2.4.2.1 Polyamide Matrices.2.4.2.2 Polyimide Matrices.2.4.2.3 Polypropylene and Polyethylene Matrices.2.4.2.4 Liquid-Crystal Matrices.2.4.2.5 Polymethylmethacrylate/Polystyrene Matrices.2.4.2.6 Epoxy and Polyurethane Matrices.2.4.2.7 Polyelectrolyte Matrices.2.4.2.8 Rubber Matrices.2.4.2.9 Others.2.4.3 Nanoparticle/Polymer Composite Processing.2.4.3.1 Direct Mixing.2.4.3.2 Solution Mixing.2.4.3.3 In-Situ Polymerization.2.4.3.4 In-Situ Particle Processing Ceramic/Polymer Composites.2.4.3.5 In-Situ Particle Processing Metal/Polymer Nanocomposites.2.4.4 Modification of Interfaces.2.4.4.1 Modification of Nanotubes.2.4.4.2 Modification of Equi-axed Nanoparticles.2.4.4.3 Small-Molecule Attachment.2.4.4.4 Polymer Coatings.2.4.4.5 Inorganic Coatings.2.5 Properties of Composites.2.5.1 Mechanical Properties.2.5.1.1 Modulus and the Load-Carrying Capability of Nanofillers.2.5.1.2 Failure Stress and Strain Toughness.2.5.1.3 Glass Transition and Relaxation Behavior.2.5.1.4 Abrasion and Wear Resistance.2.5.2 Permeability.2.5.3 Dimensional Stability.2.5.4 Thermal Stability and Flammability.2.5.5 Electrical and Optical Properties.2.5.5.1 Resistivity, Permittivity, and Breakdown Strength.2.5.5.2 Optical Clarity.2.5.5.3 Refractive Index Control.2.5.5.4 Light-Emitting Devices.2.5.5.5 Other Optical Activity.2.6 Summary.3. Natural Nanobiocomposites, Biomimetic Nanocomposites, and Biologically Inspired Nanocomposites (Paul V. Braun).3.1 Introduction.3.2 Natural Nanocomposite Materials.3.2.1 Biologically Synthesized Nanoparticles.3.2.2 Biologically Synthesized Nanostructures.3.3 Biologically Derived Synthetic Nanocomposites.3.3.1 Protein-Based Nanostructure Formation.3.3.2 DNA-Templated Nanostructure Formation.3.3.3 Protein Assembly.3.4 Biologically Inspired Nanocomposites.3.4.1 Lyotropic Liquid-Crystal Templating.3.4.2 Liquid-Crystal Templating of Thin Films.3.4.3 Block-Copolymer Templating.3.4.4 Colloidal Templating.3.5 Summary.4. Modeling of Nanocomposites (Catalin Picu and Pawel Keblinski).4.1 Introduction The Need For Modeling.4.2 Current Conceptual Frameworks.4.3 Multiscale Modeling.4.4 Multiphysics Aspects.4.5 Validation.Index.

Polymer nanocomposite dielectrics-the role of the interface

Abstract: The incorporation of silica nanoparticles into polyethylene increased the breakdown strength and voltage endurance significantly compared to the incorporation of micron scale fillers. In addition, dielectric spectroscopy showed a decrease in dielectric permittivity for the nanocomposite over the base polymer, and changes in the space charge distribution and dynamics have been documented. The most significant difference between micron scale and nanoscale fillers is the tremendous increase in interfacial area in nanocomposites. Because the interfacial region (interaction zone) is likely to be pivotal in controlling properties, the bonding between the silica and polyethylene was characterized using Fourier transformed infrared (FTTR) spectroscopy, electron paramagnetic resonance (EPR), and x-ray photoelectron spectroscopy (XPS). The picture which is emerging suggests that the enhanced interfacial zone, in addition to particle-polymer bonding, plays a very important role in determining the dielectric behavior of nanocomposites.

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology.

Abstract: Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346

Chemistry of Carbon Nanotubes

Abstract: Department of Materials Science, University of Patras, 26504 Rio Patras, Greece, Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Avenue, 116 35 Athens, Greece, Institut de Biologie Moleculaire et Cellulaire, UPR9021 CNRS, Immunologie et Chimie Therapeutiques, 67084 Strasbourg, France, and Dipartimento di Scienze Farmaceutiche, Universita di Trieste, Piazzale Europa 1, 34127 Trieste, Italy