Download or read book Thermal Conduction in Polymer Based Materials by Engineering Intermolecular Interactions written by Nitin Mehra and published by . This book was released on 2019 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Though lots of work is available in thermally conductive filler-polymer composite, clear understanding of the heat conduction mechanism in neat polymers or polymer blends is a subject of great investigation especially for the promotion and development of new thermal management technologies. This dissertation focuses on two important aspects. First, probing fundamental factors governing thermal conduction in polymers that is to understand the fundamentals factors governing the heat transport in polymer based material especially by engineering molecular level interactions in polymer chains. Second, to develop metallic/ceramic filler free thermal conductive - electrically insulative polymer based material for thermal management applications. One of the major objective of thesis is to open new avenues for thermal management using filler-free technologies for high thermal conductive and electrically insulating polymer based material for electronic packaging and advanced engineering application. Impact of intermolecular interaction in governing thermal conduction in polymers and how the quality of "thermal connections" through intermolecular interactions like hydrogen bonding can effectively drive heat propagation in polymer is shown first through a polymer hydrogen bonded with water. By engineering intermolecular interaction through hydrogen bonding in polymer chains, a significant enhancement in thermal conductivity was achieved and corresponding decrement was observed by breaking those interactions through heat. Thermal conductivity of free standing PVA films with different molecular weights and its interaction with water molecules was investigated. Further, effect of the absorption of vapor molecules of ethanol, methanol and ethylene diamine on polymer film's thermal conductivity was studied. Penetration of water molecule in films was found to drastically alter inter-molecular interaction contributing to remarkable 200% increment in thermal conductivity. Neat PVA films with lower molecular weight had higher thermal conductivity due to less dense and hindered polymer chains and ease of interaction to form continuous thermal network. After demonstrating that small molecule such as water through hydrogen bonding can significantly impact the thermal conduction, we prepared polymer blend of PEG-PVA. Thermal conduction pathways were introduced in a blend film of long chain polymer Poly (vinyl alcohol) (PVA) and short chain Poly (ethylene glycol) (PEG). Thermal conductivity enhancement of around 1.6 times of neat polymer was achieved. The critical factor responsible for thermal conduction in these films was found to be homogeneous distribution of "thermal bridges" formed by hydrogen bonding between PVA and short PEG chain. Reduction in thermal conductivity was observed when PVA blend film with longer PEG chain, which is mainly due to poor thermal bridges distribution and chain agglomeration. This work presents a fascinating yet promising non-conventional method to make thermally conductive polymer based material without using traditional fillers for thermal management applications.Size of the "thermal bridges" can have significant impact on the overall thermal conductivity of the polymer system. To further elucidate this factor, polymer blend with different molecular weight of PEG - DEG, TEG, HEG. Short chains of diethylene glycol (DEG) were incorporated into base polymer matrix of polyvinyl alcohol (PVA) which lead to remarkable thermal conductivity enhancement of 260% and 175 % than DEG and neat PVA respectively. Phonon transport was driven by the "thermal bridges" designed through intermolecular hydrogen bonding between PVA and DEG. A further impact of the length of "thermal bridges" and its functional groups (hydroxyl, carboxyl, carbonyl) at terminal position were investigated. It was found that shorter organic molecules are more efficient in driving thermal conduction owing to less inter-chain resistance. Interestingly, these materials were found to have inverse thermal conductivity-crystallinity relationship which is usually an opposite trend to the present belief.The type of intermolecular interactions formed by the terminal groups of the thermal bridging molecule can affect the phonon transport across polymer chains. We demonstrated how by employing organic molecule with hybrid terminal groups resulted in enhanced thermal conductivity than the bulk polymer. The highest thermal conductivity of 0.55 W/m·K was achieved when organic molecule with hybrid terminal groups was incorporated in base polymer. Engineering intermolecular interaction helps to create continuous thermal network which facilitates phonon transport. The hybrid thermal bridges created with the base polymer act as synergistic center which further boost phonon transport. Interestingly, such thermal conductivity enhancement with hybrid terminal groups was found both in amorphous and crystalline organic molecules. Further, such molecules were incorporated in polymer chains with different backbone structure. PVA with different degree of hydrolysis was selected. Due to the presence of a bulkier acetyl group in PVA with lower degree of hydrolysis thermal conduction was hindered and vice-versa.At last, multiple hydrogen bonded pathways were created for effective phonon transport via supramolecular chemistry. Melamine-Cyanurate (MC), a multiple hydrogen bonded supramolecular filler was employed for this purpose. It has remarkable potential to develop self-assembled 2-D layered sheet structure at the same time strengthening thermal interfaces. This resulted in composite thermal conductivity of 1.65 times the thermal conductivity of neat PVA at 50 wt % loading. Such composite is prepared by non-conventional mixing by in-situ co-precipitation of filler resulting in homogenous distribution.

Download or read book Polymer Based Multifunctional Nanocomposites and Their Applications written by John Zhanhu Guo and published by Elsevier. This book was released on 2018-09-14 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymer-Based Multifunctional Nanocomposites and Their Applications provides an up-to-date review of the latest advances and developments in the field of polymer nanocomposites. It will serve as a one-stop reference resource on important research accomplishments in the area of multifunctional nanocomposites, with a particular emphasis placed on the use of nanofillers and different functionality combinations. Edited and written by an expert team of researchers in the field, the book provides a practical analysis of functional polymers, nanoscience, and nanotechnology in important and developing areas, such as transportation engineering, mechanical systems, aerospace manufacturing, construction materials, and more. The book covers both theory and experimental results regarding the relationships between the effective properties of polymer composites and those of polymer matrices and reinforcements. Presents a thorough and up-to-date review of the latest advances and developments in the field of multifunctional polymer nanocomposites Integrates coverage of fundamentals, research and development, and the range of applications for multifunctional polymers and their composites, such as in the automotive, aerospace, biomedical and electrical industries Supports further technological developments by discussing both theory and real world experimental data from academia and industry

Download or read book Manipulating Thermal Transport in Soft Materials written by Joseph Samuel Katz and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electronics are ubiquitous, playing significant roles in modern work, entertainment, medicine, and myriad other aspects of our lives. As the new applications have grown, so too has the variety of chips. Unique product requirements accompany each particular application, but the demand for simultaneous protection from and interaction with the outside environment has driven the growth of a specialized field within electronics: packaging. The package protects the chip from damage during assembly and operation, makes electrical connections between the chip and the exterior electronics (often a printed circuit board), accommodates stresses due to thermal expansion, and facilitates heat removal from the chip. High thermal conductivity and mechanical compliance are both desirable in electronics packaging materials but tend to be mutually exclusive in naturally occurring materials. The development of highly conductive and compliant materials has long focused on the addition of inorganic fillers to an organic matrix, compromising some of the compliance of the polymer in exchange for some of the conductivity of the filler. Recent research has demonstrated the possibility for greater progress by approaching the problem from different directions: (1) increasing the thermal conductivity of the polymer without any filler material by manipulating the inter- and intra-molecular interactions, and (2) increasing the compliance of thermally conductive inorganic materials through nanoscale porosity. This work incorporates contributions to both of these directions. First, several experiments on spin coated polystyrene are presented. The macromolecular alignment due to the shear forces from spin coating was hypothesized to increase thermal conductivity in the direction of the alignment. The measurements in the vertical, radial, and azimuthal direction of the films suggest that the spin coating process did not significantly alter the thermal conductivity relative to the bulk polymer. This was found to be true even for bottlebrush polystyrene samples, with long side chains elongating the polymer to a gyration radius of ~100 nm. In the process of executing this measurement, multiple novel fabrication processes were developed to avoid damaging the sensitive polymer samples with caustic fabrication steps intended for more robust, inorganic materials. In particular, two different processes are presented in order to fabricate metal lines with sub-micron widths on polymer samples to perform 3-omega thermal conductivity measurements. The first, a nanostencil process, almost completely decouples lithography and etching from the sample by patterning membranes with desired features that are then used as shadow masks. The second uses room-temperature lithography to avoid thermal expansion mismatch between metal and polymer layers. Second, bifurcated 3-omega measurements of polystyrene (PS) and poly(4-chlorostyrene) (P4ClS) are performed, offering insight into the role of electrostatic intermolecular interactions in thermal conduction. The enhanced dipole moment in P4ClS was hypothesized to increase the thermal conductivity by strengthening the intermolecular interactions, but the difference in thermal conductivity between PS and P4ClS was found to be within the uncertainty. Finally, a novel technique to prepare nickel and gold films with tunable pore size and porosity is presented. The pore sizes range from 30 nm to 45 nm and the porosity from 35% to 65%. The electrical resistivities are also measured and found to be in agreement with a percolation-based effective medium theory including size effects. Each of these experiments individually addresses a specific question regarding material preparation, device fabrication, or thermal transport. In aggregate, the goal of this work is to inform the design of high thermal conductivity compliant materials. Further enhancements in packaging materials following this work and others will continue to make modern electronics more efficient and bring unprecedented electronic applications to reality.

Download or read book Materials written by Witold Brostow and published by John Wiley & Sons. This book was released on 2016-10-10 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents a fully interdisciplinary approach with a stronger emphasis on polymers and composites than traditional materials books Materials science and engineering is an interdisciplinary field involving the properties of matter and its applications to various areas of science and engineering. Polymer materials are often mixed with inorganic materials to enhance their mechanical, electrical, thermal, and physical properties. Materials: Introduction and Applications addresses a gap in the existing textbooks on materials science. This book focuses on three Units. The first, Foundations, includes basic materials topics from Intermolecular Forces and Thermodynamics and Phase Diagrams to Crystalline and Non-Crystalline Structures. The second Units, Materials, goes into the details of many materials including Metals, Ceramics, Organic Raw Materials, Polymers, Composites, Biomaterials, and Liquid Crystals and Smart Materials. The third and final unit details Behavior and Properties including Rheological, Mechanical, Thermophysical, Color and Optical, Electrical and Dielectric, Magnetic, Surface Behavior and Tribology, Materials, Environment and Sustainability, and Testing of Materials. Materials: Introduction and Applications features: Basic and advanced Materials concepts Interdisciplinary information that is otherwise scattered consolidated into one work Links to everyday life application like electronics, airplanes, and dental materials Certain topics to be discussed in this textbook are more advanced. These will be presented in shaded gray boxes providing a two-level approach. Depending on whether you are a student of Mechanical Engineering, Electrical Engineering, Engineering Technology, MSE, Chemistry, Physics, etc., you can decide for yourself whether a topic presented on a more advanced level is not important for you—or else essential for you given your professional profile Witold Brostow is Regents Professor of Materials Science and Engineering at the University of North Texas. He is President of the International Council on Materials Education and President of the Scientific Committee of the POLYCHAR World Forum on Advanced Material (42 member countries). He has three honorary doctorates and is a Member of the European Academy of Sciences, Member of the National Academy of Sciences of Mexico, Foreign Member of the National Academy of Engineering of Georgia in Tbilisi and Fellow of the Royal Society of Chemistry in London. His publications have been cited more than 7200 times. Haley Hagg Lobland is the Associate Director of LAPOM at the University of North Texas. She is a Member of the POLYCHAR Scientific Committeee. She has received awards for her research presented at conferences in: Buzios, Rio de Janeiro, Brazil; NIST, Frederick, Maryland; Rouen, France; and Lviv, Ukraine. She has lectured in a number of countries including Poland and Spain. Her publications include joint ones with colleagues in Egypt, Georgia, Germany, India, Israel, Mexico, Poland, Turkey and United Kingdom.

Download or read book Tailoring Intermolecular Interactions in Methacrylate based Copolymers and Nanocomposites written by Valentina Cavallo and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Technical Nonwovens written by George Kellie and published by Woodhead Publishing. This book was released on 2016-05-17 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Technical Nonwovens presents the latest information on the nonwovens industry, a dynamic and fast-growing industry with recent technological innovations that are leading to the development of novel end-use applications. The book reviews key developments in technical nonwoven manufacturing, specialist materials, and applications, with Part One covering important developments in materials and manufacturing technologies, including chapters devoted to fibers for technical nonwovens, the use of green recycled and biopolymer materials, and the application of nanofibres. The testing of nonwoven properties and the specialist area of composite nonwovens are also reviewed, with Part Two offering a detailed and wide-ranging overview of the many applications of technical nonwovens that includes chapters on automotive textiles, filtration, energy applications, geo- and agrotextiles, construction, furnishing, packaging and medical and hygiene products. Provides systematic coverage of trends, developments, and new technology in the field of technical nonwovens Focuses on the needs of the nonwovens industry with a clear emphasis on applied technology Contains contributions from an international team of authors edited by an expert in the field Offers a detailed and wide-ranging overview of the many applications of technical nonwovens that includes chapters on automotive textiles, filtration, energy applications, geo- and agrotextiles, and more

Download or read book Thermal Conductivity of Polypropylene Based Materials written by Antonella Patti and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, the authors aimed to provide an overview about the thermal conductivity of polypropylene, of its related compounds and the main methods of measurement. The growing spread of polypropylene in the industrial world together with the increasing demand of thermally conductive plastics represented the driving force of studying the heat transport in the polypropylene, and of recent progress and development of the thermal conduction in polypropylene-based materials. At regard, the common approach has been devoted to fill the polymer with thermally conductive materials: metallic, carbon based, ceramic and mineral fillers have been taken into account depending on the need to preserve electrical insulation, lightweight, production increasing or cost saving in the final compositions. Different parameters have been considered in order to optimize the ultimate thermal performances in the realized composites: (i) filler dispersion, (ii) filler/matrix and filler/filler interactions. The introduction of functional groups on the filler surface or in the polymer chain has been tested for acting on the dispersion and on the interfacial interaction. Then, hybrid materials, consisting in two particles different in size and shape combined with the attempt to realize a synergistic effect and to support a conductive network in the matrix, have been investigated.

Download or read book Flame Retardant and Thermally Insulating Polymers written by Yanfei Xu and published by BoD – Books on Demand. This book was released on 2021-09-08 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers have infiltrated almost every aspect of modern technology, as they have wide applications ranging from building insulation and firefighter uniforms to the Boeing 787 Dreamliner aircraft and electronics packaging. However, common polymers are flammable. Inflammability and thermal insulation properties in polymers are important for specific applications. This book discusses recent advances in developing eco-friendly, flame-retardant, and thermally insulative polymer-based materials. It not only focuses on developments of high-performance flame retardants, but also examines flame retardant behaviors in polymers. Eco-friendly polymers with superior flame retardancy, extraordinary thermal insulation, and excellent mechanical strength will provide new opportunities for existing and future applications.

Download or read book Polymer Nanocomposites written by Xingyi Huang and published by Springer. This book was released on 2016-05-06 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the fundamental principles and recent progress in the field of electrical and thermal properties of polymer nanocomposites. The physical and chemical natures determining the electrical and thermal properties of polymer nanocomposites are discussed in detail. The authors describe the range of traditional and emerging polymer nanocomposites from nanoparticle and polymer composites to novel nanostructure based polymer nanocomposites. They include novel properties and potential applications, such as high-k, low-k, high thermal conductivity, antistatic, high voltage insulation, electric stress control, and thermal energy conversion among others.

Download or read book Heat Transfer in Polymer Composite Materials written by Nicolas Boyard and published by John Wiley & Sons. This book was released on 2016-03-28 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses general information, good practices and examples about thermo-physical properties, thermo-kinetic and thermo-mechanical couplings, instrumentation in thermal science, thermal optimization and infrared radiation.

Download or read book Frontiers in Chemical Engineering written by National Research Council and published by National Academies Press. This book was released on 1988-02-01 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the next 10 to 15 years, chemical engineers have the potential to affect every aspect of American life and promote the scientific and industrial leadership of the United States. Frontiers in Chemical Engineering explores the opportunities available and gives a blueprint for turning a multitude of promising visions into realities. It also examines the likely changes in how chemical engineers will be educated and take their place in the profession, and presents new research opportunities.

Download or read book Carbon Nanotube Polymer Composites written by Dimitrios Tasis and published by Royal Society of Chemistry. This book was released on 2015-11-09 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemically-modified carbon nanotubes (CNTs) exhibit a wide range of physical and chemical properties which makes them an attractive starting material for the preparation of super-strong and highly-conductive fibres and films. Much information is available across the primary literature, making it difficult to obtain an overall picture of the state-of-the-art. This volume brings together some of the leading researchers in the field from across the globe to present the potential these materials have, not only in developing and characterising novel materials but also the devices which can be fabricated from them. Topics featured in the book include Raman characterisation, industrial polymer materials, actuators and sensors and polymer reinforcement, with chapters prepared by highly-cited authors from across the globe. A valuable handbook for any academic or industrial laboratory, this book will appeal to newcomers to the field and established researchers alike.

Download or read book Chemical Synthesis and Applications of Graphene and Carbon Materials written by Markus Antonietti and published by John Wiley & Sons. This book was released on 2017-03-20 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: This ready reference and handbook is unique in its focus on synthesis and the application of graphene and other carbon materials with an emphasis on chemistry aspects. To this extent, it deals with top-down and bottom-up approaches across the different length scales for graphene from polycyclic aromatic hydrocarbons to graphene nanoribbons and graphene sheets, as well as carbon materials from quantum dots, nanostructured particles, and fibers, right up to tubes, bulk structures, and much more besides. In so doing, it presents the best synthetic methods: pyrolysis, chemical vapor deposition, templating and surface-mediated synthesis, self-assembly, surface-grafting and modification. Edited by two excellent, experienced and highly renowned editors, both of whom are directors of Max Planck Institutes.

Download or read book The Chemistry of Polymers written by Margaret Morris and published by . This book was released on 2020-09-22 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: The scientific field that is concerned with the chemical synthesis, structure, and the physical and chemical properties of polymers and macromolecules is known as polymer chemistry. Its principles and methods are also applicable in a variety of sub-disciplines of chemistry such as organic chemistry, physical chemistry and analytical chemistry. On the basis of their origin, polymers are subdivided into biopolymers and synthetic polymers. The functional and structural materials that make most of the organic matter in organisms are biopolymers. Synthetic polymers are the structural materials that are manifested in synthetic fibers, paints, building materials, furniture, plastics, mechanical parts and adhesives. This book is a compilation of chapters that discuss the most vital concepts in the field of polymer chemistry. Some of the diverse topics covered herein address the varied branches that fall under this category. Those in search of information to further their knowledge will be greatly assisted by this book.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1989 with total page 1134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Polymer Blends written by Sabu Thomas and published by John Wiley & Sons. This book was released on 2015-02-09 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt: Filling the gap for a reference dedicated to the characterization of polymer blends and their micro and nano morphologies, this book provides comprehensive, systematic coverage in a one-stop, two-volume resource for all those working in the field. Leading researchers from industry and academia, as well as from government and private research institutions around the world summarize recent technical advances in chapters devoted to their individual contributions. In so doing, they examine a wide range of modern characterization techniques, from microscopy and spectroscopy to diffraction, thermal analysis, rheology, mechanical measurements and chromatography. These methods are compared with each other to assist in determining the best solution for both fundamental and applied problems, paying attention to the characterization of nanoscale miscibility and interfaces, both in blends involving copolymers and in immiscible blends. The thermodynamics, miscibility, phase separation, morphology and interfaces in polymer blends are also discussed in light of new insights involving the nanoscopic scale. Finally, the authors detail the processing-morphology-property relationships of polymer blends, as well as the influence of processing on the generation of micro and nano morphologies, and the dependence of these morphologies on the properties of blends. Hot topics such as compatibilization through nanoparticles, miscibility of new biopolymers and nanoscale investigations of interfaces in blends are also addressed. With its application-oriented approach, handpicked selection of topics and expert contributors, this is an outstanding survey for anyone involved in the field of polymer blends for advanced technologies.

Download or read book Organic Optoelectronic Materials written by Yongfang Li and published by Springer. This book was released on 2015-05-30 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume reviews the latest trends in organic optoelectronic materials. Each comprehensive chapter allows graduate students and newcomers to the field to grasp the basics, whilst also ensuring that they have the most up-to-date overview of the latest research. Topics include: organic conductors and semiconductors; conducting polymers and conjugated polymer semiconductors, as well as their applications in organic field-effect-transistors; organic light-emitting diodes; and organic photovoltaics and transparent conducting electrodes. The molecular structures, synthesis methods, physicochemical and optoelectronic properties of the organic optoelectronic materials are also introduced and described in detail. The authors also elucidate the structures and working mechanisms of organic optoelectronic devices and outline fundamental scientific problems and future research directions. This volume is invaluable to all those interested in organic optoelectronic materials.