Download or read book Effects of Trisilanol Polyhedral Silsesquioxanes Additions on Aluminum Alloys written by Yuxiang Zhong and published by . This book was released on 2019 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the automotive industry, aluminum alloys are of particular interests in providing the fuel economy needed to meet the required Corporate Average Fuel Economy (CAFE) standards. Current commercial cast aluminum alloys use Strontium (Sr) to modify the eutectic silicon morphology leading to improve ductility. However, the fading of Sr addition effect at the molten temperature remains as a major concern. Recently, it was demonstrated that the addition of nanostructured silanol based on polyhedral silsesquioxanes to cast aluminum alloys provided the refinement of eutectic silicon morphology without fading when held at molten temperature up to 96 hours. In addition, using master ingots containing nanostructured silanols, large-scale commercial alloys have been successfully modified.In this work, aluminum coated with nanostructured silanol of different chemical moieties were investigated. The contact angle measurement and powder sedimentation experiments have shown the increase in the hydrophobicity with nanostructured silanol coating. In addition, durability of the coating was also examined. Secondly, we investigated the electrochemical behavior of several casted aluminum alloys. The open circuit potential measurement and potentiodynamic polarization measurement show that the microstructure refinement with Sr or TSP will not affect the corrosion behavior on the hypo-eutectic Al-Si alloys but will reduce the anodic current density of the eutectic Al-Si alloys.

Download or read book A Novel Approach for Property Modification of Cast Aluminum Alloys with Nanostructured Chemical Additions written by Yang Lu and published by . This book was released on 2019 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: Continued weight reduction which involves replacing steel components with lightweight materials is one of the major strategies to achieve the average fuel economy standards in the automotive industry. Based on the significant success of aluminum alloys in non-structural components, aluminum alloys in structural applications attract particular interest. To this end, the ultimate objective is to achieve aluminum alloys with high ductility and strength. However, conventional aluminum-silicon (Al-Si) based casting alloys possess low ductility as compensation for the required high strength, since the presence of irregular eutectic silicon crystals in the as-cast condition promotes crack initiation and propagation. Strontium (Sr) is widely used to modify the Si eutectic in commercially available "high ductility" cast aluminum alloys. However, fading issues arise due to Sr oxidation at the casting temperature, and become major concerns for aluminum foundries. Therefore, it is important to develop a universal modifier that can be used in alloys with a larger range of Si content. In this thesis, trisilanol polyhedral silsesquioxane (TSP) was first incorporated in Sn-based binary and ternary alloys, leading to microstructure refinement and high creep resistance. Based on these preliminary results, TSP was further applied to Al based alloys. First, TSP was coated on Al-12Si powders using dip-coating approach. After melting, the microstructure of both primary Al and eutectic microconstituents of Al-12Si ingots was refined. Ductility increased from 5% with no TSP treatment to 18% when treated with TSP. More interestingly, the modified structure was maintained with 150 ppm of TSP addition. The incorporation of TSP reduced the undercooling and arrest temperatures of Al-Si eutectic during solidification. These results suggest TSP bonds with Al to slow down the Al segregation from Al-Si melt during eutectic reaction, leading to the microstructural refinement of Al-Si eutectic microconstituents. Based on the laboratory-scale results, a new TSP master was produced to facilitate the incorporation of TSP into traditional foundry process. The optimized master composition contained 6%TSP in an Al-12Si alloy, and 10% Al-12Si-6TSP master was applied to modify Al-Si binary and commercial alloys at a 100 lbs. scale. In Al-Si binary alloys, TSP addition results 50% improvement in ductility over the Al-7.5Si base alloy without sacrificing the strength. The microstructure of both primary Al and eutectic microconstituents of the Al-7.5Si alloy with TSP addition was refined. Minimal fade was observed up to a 192-hour hold at 720°C, which sheds light on the Sr fading issue. In Aural(TM) 2 and W319 -type commercial alloys, TSP additions reduced the solidification shrinkage of castings. Metallography showed refined Si in the Al-Si eutectic microconstituent and reduced Al secondary dendrite arm spacing (SDAS), resulting in an 100% improvement in ductility without sacrificing strength. Besides microstructural refinement, the mass fraction of theta (Al2Cu) increased while Q (Al4Cu2Mg8Si7) decreased with TSP addition, suggesting TSP changes the Cu intermetallic compounds (IMCs) to favor the formation of theta, which demonstrated its potential as a strengthening precipitate. This study addresses fundamental questions on how the addition of TSP influences microstructure and solidification behavior of Al-Si based casting alloys, thus providing solutions to reinforce aluminum alloys in body structures for the environmental and fuel economy benefits.

Download or read book Polyhedral Oligomeric Silsesquioxane POSS Polymer Nanocomposites written by Sabu Thomas and published by Elsevier. This book was released on 2021-03-25 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polyhedral Oligomeric Silsesquioxane (POSS) Polymer Nanocomposites: From Synthesis to Applications offers extensive coverage of polyhedral oligomeric silsesquioxanes and their nanocomposites, including their synthesis, characterization, interfacial interactions and advanced applications. Sections introduce essentials, information on their preparation and discussions on polymeric materials, including elastomers, thermoplastics, thermosetting polymers, polymer blends and IPNs. Further sections cover the latest analysis techniques, examine the properties of POSS-polymer nanocomposites, and discuss key application areas, such as biological, energy, defense, and space. Finally, issues surrounding industry implementation and lifecycle are explored. This is a valuable reference for researchers, scientists and advanced students in the areas of polymer composites and nanocomposites, polymer chemistry, polymer physics, polymer science, and materials science and engineering. In an industrial setting, this book will be of great interest to scientists, R&D professionals, and engineers across industries and disciplines. Covers all aspects of polyhedral oligomeric silsesquioxanes (POSS) and their nanocomposites, including synthesis and characterization techniques, properties, analysis, applications and trends Targets POSS nanocomposites, describing synthesis, characterization and the selection of POSS filler types according to polymeric material Explains the preparation and utilization of POSS polymer nanocomposites for cutting-edge applications, including biological, energy, and defense field applications

Download or read book Polymer POSS Nanocomposites and Hybrid Materials written by Susheel Kalia and published by Springer. This book was released on 2018-11-27 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an overview of polymer nanocomposites and hybrid materials with polyhedral oligomeric silsesquioxanes (POSS). Among inorganic nanoparticles, functionalized POSS are unique nano-building blocks that can be used to create a wide variety of hybrid and composite materials, where precise control of nanostructures and properties is required. This book describes the influence of incorporation of POSS moieties into (organic) polymer matrices on the mechanical, thermal and flammability behavior of composites and hybrid organic-inorganic materials. Importantly, POSS-containing materials can be bio-functionalized by linking e.g. peptides and growth factors through appropriate surface modification in order to enhance the haemo-compatibility of cardiovascular devices made of these materials. This volume includes descriptions of synthesis routes of POSS and POSS-containing polymeric materials (e.g. based on polyolefines, epoxy resins and polyurethanes), presentation of POSS’ role as flame retardants and as biocompatible linker, as well as the depiction of decomposition and ageing processes.

Download or read book Handbook of Benzoxazine Resins written by Hatsuo Ishida and published by Elsevier. This book was released on 2011-07-13 with total page 709 pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook provides a wide overview of the field, fundamental understanding of the synthetic methods and structure/property correlation, as well as studies related to applications in a wide range of subjects. The handbook also provides 1H and 13C NMR spectra, FTIR spectra, DSC and TGA thermograms to aid in research activities. Additional tables on key NMR and FTIR frequencies unique to benzoxazine, heat of polymerization, Tg, and char yield will greatly aid in the choice of proper benzoxazine for a specific application. Provides thorough coverage of the chemistry and applications of benzoxazine resins with an evidence-based approach to enable chemists, engineers and material scientists to evaluate effectiveness Features spectra, which allow researchers to compare results, avoid repetition and save time as well as tables on key NMR frequency, IR frequency, heat of polymerization, of many benzoxazine resins to aid them in selection of materials Written by the foremost experts in the field

Download or read book Ceramic Catalysts written by Manju Kurian and published by Elsevier. This book was released on 2023-04-27 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ceramic Catalysts: Materials, Strategies and Applications focuses on synthesis techniques and applications of ceramic materials in heterogenous catalysis. In order to enable an affordable, sustainable, low-carbon economy, research activities have been intensified in this area over recent years. The rapid accumulation of results has been evaluated and summarized by recognized experts working in their respective fields in the form of separate and complementary chapters. The first part of the book is dedicated to synthesis and catalytic applications of different categories of ceramics that include both porous ceramics and ceramic composites. Catalytic applications of ceramics mainly involving waste-water treatment, combustion reactions, and fine chemical synthesis are also discussed. Use of ceramics as catalyst supports is also given importance in the book. The book is intended to act as a valuable reference resource for both researchers and postgraduate students with key emphasis on the following areas of research: Recent techniques for the synthesis of different ceramics; specific characteristics of each type of ceramics for catalytic applications; different types of catalyzed reactions based on inherent chemical characteristics and sustainable technologies based on ceramic catalysts.The book will be an essential reference resource for industrial and academic researchers, materials scientists, chemists, and environmental scientists. Provides an extensive overview of ceramic materials involved in catalysis Presents the current state of art as tremendous progress has been achieved over recent years Contributors are at the forefront of research Provides an evaluation and comparison of the different types of ceramic materials available, including structure, properties and performance

Download or read book Nanocomposite Materials written by Jyotishkumar Parameswaranpillai and published by CRC Press. This book was released on 2016-09-19 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive collection of the latest information on nanomaterials and nanocomposites. It covers material synthesis, processing, structure characterization, properties and applications. It presents a coherent treatment of how composite properties depend on nanostructure, and covers cutting-edge topics like bionanocomposites for sustainable development. This book summarizes many developments in the field making it an ideal resource for researchers from industry, academia, government and private research institutions.

Download or read book POSS Based Polymers written by Ignazio Blanco and published by MDPI. This book was released on 2019-12-19 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: The combination of functional polymers with inorganic nanostructured compounds has become a major area of research and technological development owing to the remarkable properties and multifunctionalities deriving from their nano and hybrid structures. In this context, polyhedral oligomeric silsesquioxanes (POSSs) have increasing importance and a dominant position with respect to the reinforcement of polymeric materials. Although POSSs were first described in 1946 by Scott, these materials, however, have not immediately been successful if we consider that, starting from 1946 and up to 1995, we find in the literature 85 manuscripts regarding POSSs; which means that less than two papers per year were published over 50 years. Since 1995, we observe an exponential growth of scientific manuscripts concerning POSSs. It is changing from an annual average of 20 manuscripts for the period 1995–2000 to an annual average of about 400 manuscripts, with an increase of 2800%. The introduction of POSSs inorganic nanostructures into polymers gives rise to polymer nanostructured materials (PNMs) with interesting mechanical and physical properties, thus representing a radical alternative to the traditional filled polymers or polymer compositions.

Download or read book Applications of Polyhedral Oligomeric Silsesquioxanes written by Claire Hartmann-Thompson and published by Springer Science & Business Media. This book was released on 2011-01-03 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: The commercial availability and decreasing cost of polyhedral oligomeric silsesquioxanes in recent years has opened up the field to everybody who wishes to apply these unique properties in their own technologies. This is the first book to provide a comprehensive overview of these applications, and covers the synthesis, characterization and history of polyhedral oligomeric silsesquioxanes, their use as metallasilsesquioxane catalysts, their effect upon polymer properties and plastics performance, and their use in superhydrophobic nanocomposites, and electronics, energy, space and biomedical applications. "Applications of Polyhedral Oligomeric Silsesquioxanes" is a valuable reference for those working across a range of disciplines, including chemists, materials scientists, polymer physicists, plastics engineers, surface scientists, and anybody with a commercial or academic interest in plastics, composite materials, space materials, dental materials, tissue engineering, drug delivery, lithography, fuel cells, batteries, lubricants, or liquid crystal, LED, sensor, photovoltaic or biomedical devices.

Download or read book Functional Polymer Coatings written by Limin Wu and published by John Wiley & Sons. This book was released on 2015-06-15 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focusing on a variety of coatings, this book provides detailed discussion on preparation, novel techniques, recent developments, and design theories to present the advantages of each function and provide the tools for better product performance and properties. • Presents advantages and benefits of properties and applications of the novel coating types • Includes chapters on specific and novel coatings, like nanocomposite, surface wettability tunable, stimuli-responsive, anti-fouling, antibacterial, self-healing, and structural coloring • Provides detailed discussion on recent developments in the field as well as current and future perspectives • Acts as a guide for polymer and materials researchers in optimizing polymer coating properties and increasing product performance

Download or read book Lead Free Electronic Solders written by KV Subramanian and published by Springer Science & Business Media. This book was released on 2007-06-28 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Even though the effect of lead contamination on human health has been known for decades, very little attention has been paid to lead-based solders used in electronics until recently. This comprehensive book examines all the important issues associated with lead-free electronic solder. It collects the work of researchers recognized for their significant scientific contributions in the area.

Download or read book Polyurethane Elastomers written by Cristina Prisacariu and published by Springer Science & Business Media. This book was released on 2011-07-03 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive account of the physical / mechanical behaviour of polyurethanes (PU ́s) elastomers, films and blends of variable crystallinity. Aspects covered include the elasticity and inelasticity of amorphous to crystalline PUs, in relation to their sensitivity to chemical and physical structure. A study is made of how aspects of the constitutive responses of PUs vary with composition: the polyaddition procedure, the hard segment, soft segment and chain extender (diols and diamines) are varied systematically in a large number of systems of model and novel crosslinked andthermoplastic PUs. Results will be related to: microstructural changes, on the basis of evidence from x-ray scattering (SAXS and WAXS), and also dynamic mechanical analyses (DMA), differential scanning calorimetry (DSC) and IR dichroism. Inelastic effects will be investigated also by including quantitative correlations between the magnitude of the Mullins effect and the fractional energy dissipation by hysteresis under cyclic straining, giving common relations approached by all the materials studied. A major structural feature explored is the relationship between the nature of the hard segment (crystallising or not) and that of the soft segments. Crystallinity has been sometimes observed in the commercial PUs hard phase but this is usually limited to only a few percent for most hard segment structures when solidified from the melt. One particular diisocyanate, 4,4’-dibenzyl diisocyanate (DBDI) that, in the presence of suitable chain extenders ( diols or diamines), gives rise to significant degrees of crystallinity [i-iii] and this is included in the present work. Understanding the reaction pathways involved, in resolving the subtle morphological evolution at the nanometre level, and capturing mathematically the complex, large-deformation nonlinear viscoelastic mechanical behaviour are assumed to bring new important insights in the world basic research in polyurethanes and towards applied industrial research in this area.

Download or read book Handbook of Thermoset Plastics written by Olga Shepelev and published by Elsevier Inc. Chapters. This book was released on 2013-11-28 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: With recent developments in nanotechnology, thermoset nanocomposites offer numerous advantages compared to conventional composite materials. Moreover, with the emergence of commercial nanomaterials like nanoclays (NCs), carbon nanotubes (CNTs), nanosilica (NS), Polyhedral-Oligomeric-Sil-Sesquioxanes (POSS), tungsten-disulfide (WS2) fullerenes and tubes, and Graphene (Gr), new potential routes have been opened to tailor thermosetting polymers in the nanoscale range. Due to the large surface area of the nanosize particles, only small amounts are needed to cause significant changes in the mechanical, physical, and thermal properties of polymer nanocomposites. When the surface areas of the nanoparticles are modified, additional dimensions for the formulation of structural adhesives and composite matrices arise, and can be used for a variety of applications. The formulation sequence and conditions are found to determine the structure and properties of the resulting nanocomposites. This chapter reviews and analyzes the various thermoset nanocomposites containing: NCs, CNTs, NS, POSS, WS2, and Gr.

Download or read book Functional Molecular Silicon Compounds I written by David Scheschkewitz and published by Springer. This book was released on 2014-07-08 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Structure and Bonding publishes critical reviews on topics of research concerned with chemical structure and bonding. The scope of the series spans the entire Periodic Table and addresses structure and bonding issues associated with all of the elements. It also focuses attention on new and developing areas of modern structural and theoretical chemistry such as nanostructures, molecular electronics, designed molecular solids, surfaces, metal clusters and supramolecular structures. Physical and spectroscopic techniques used to determine, examine and model structures fall within the purview of Structure and Bonding to the extent that the focus is on the scientific results obtained and not on specialist information concerning the techniques themselves. Issues associated with the development of bonding models and generalizations that illuminate the reactivity pathways and rates of chemical processes are also relevant. The individual volumes in the series are thematic. The goal of each volume is to give the reader, whether at a university or in industry, a comprehensive overview of an area where new insights are emerging that are of interest to a larger scientific audience. Thus each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years should be presented using selected examples to illustrate the principles discussed. A description of the physical basis of the experimental techniques that have been used to provide the primary data may also be appropriate, if it has not been covered in detail elsewhere. The coverage need not be exhaustive in data, but should rather be conceptual, concentrating on the new principles being developed that will allow the reader, who is not a specialist in the area covered, to understand the data presented. Discussion of possible future research directions in the area is welcomed. Review articles for the individual volumes are invited by the volume editors. Readership: research scientists at universities or in industry, graduate students Special offer For all customers who have a standing order to the print version of Structure and Bonding, we offer free access to the electronic volumes of the Series published in the current year via SpringerLink.

Download or read book Silicon Containing Polymers written by Richard G Jones and published by Royal Society of Chemistry. This book was released on 2023-09-08 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Silicon-containing Polymers reflects the growing interest worldwide in this developing field. Silicon polymers are now finding use as moulding materials, rubbers, ceramic precursors, in lithography and reprography as photosensitive materials, as conducting polymers, and in a host of other applications. This book presents up-to-date research from all over the world. It brings together research from the forefront of a multidisciplinary subject, covering the synthesis, modification, characterization, properties and applications of polysiloxanes, polysilylenes, polysilazanes and organosilicate derivatives. Silicon-containing Polymers will be of interest to researchers and postgraduates in any area of materials science, as well as some areas of inorganic chemistry.

Download or read book Hybrid Organic Inorganic Interfaces written by Marie Helene Delville and published by John Wiley & Sons. This book was released on 2018-04-09 with total page 1010 pages. Available in PDF, EPUB and Kindle. Book excerpt: Das erste Handbuch und gut zugängliche Referenzwerk zu diesem zunehmend wichtigen Thema erläutert in einem anwendungsorientierten Ansatz Synthese, Design, Charakterisierung und Simulation von Grenzflächen bei hybriden organisch-anorganischen Materialien.

Download or read book Reactive Oligomers written by Frank Wayne Harris and published by . This book was released on 1985 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Serves as the first book to look at the many applications of various types of oligomers. Describes oligomer synthesis and subsequent reactions by cationic, anionic, free radical, and condensation techniques. Reports on different applications with similar research approaches, including composite resins, electronic coatings, high solids paints, and more.