Download or read book Structure and Relaxation of Thin Glass Forming Polymer Films written by Simone Peter and published by . This book was released on 2007 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nous avons utilisé des simulations de dynamique moléculaire pour étudier des films ultra-fins de polymères, à l'aide d'un modèle coarse-grained. Nous avons analysé la dynamique au sein du film, aussi bien en moyenne que par couches en fonction de la distance à la surface. Nous avons déterminé la température de transition vitreuse Tg au cours de refroidissements. Il ressort de ces études que la dynamique est accélérée dans les couches minces par rapport à la situation du fondu en volume, et Tg diminue. Des films de polymères en solution ont également été étudiés en présence d'un solvant explicite. Nous nous sommes intéressés à la formation de films de polymères purs par évaporation du solvant; les résultats obtenus montrent que la dynamique est plus rapide et Tg plus basse en présence du solvant. Alors que nous pouvons observer une diffusion fickienne à des températures supérieures à Tg, pour des températures plus basses, les déviations par rapport à ce comportement sont notables.
Download or read book Antiplasticization in a Confined Polymer Glass written by Robert Andrew Riggleman and published by . This book was released on 2007 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Interfacial Mobility in Glass Forming Thin Films written by Fedir Demydiuk and published by . This book was released on 2021* with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supported polymer films, polybutadiene, molecular dynamics simulations, glass transition, dielectric relaxation, relaxation gradients, intramolecular barriers.
Download or read book Polymer Glasses written by Connie B. Roth and published by CRC Press. This book was released on 2016-12-12 with total page 587 pages. Available in PDF, EPUB and Kindle. Book excerpt: "the present book will be of great value for both newcomers to the field and mature active researchers by serving as a coherent and timely introduction to some of the modern approaches, ideas, results, emerging understanding, and many open questions in this fascinating field of polymer glasses, supercooled liquids, and thin films" –Kenneth S. Schweizer, Morris Professor of Materials Science & Engineering, University of Illinois at Urbana-Champaign (from the Foreword) This book provides a timely and comprehensive overview of molecular level insights into polymer glasses in confined geometries and under deformation. Polymer glasses have become ubiquitous to our daily life, from the polycarbonate eyeglass lenses on the end of our nose to large acrylic glass panes holding water in aquarium tanks, with advantages over glass in that they are lightweight and easy to manufacture, while remaining transparent and rigid. The contents include an introduction to the field, as well as state of the art investigations. Chapters delve into studies of commonalities across different types of glass formers (polymers, small molecules, colloids, and granular materials), which have enabled microscopic and molecular level frameworks to be developed. The authors show how glass formers are modeled across different systems, thereby leading to treatments for polymer glasses with first-principle based approaches and molecular level detail. Readers across disciplines will benefit from this topical overview summarizing the key areas of polymer glasses, alongside an introduction to the main principles and approaches.
Download or read book The Glass Transition written by E. Donth and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes and interrelates the following processes: cooperative alpha processes in a cold liquid, structural relaxation in the glass near Tg, the Johari-Goldstein beta process, the Williams-Götze process in a warm liquid, fast nonactivated cage rattling and boson peak, and ultraslow Fischer modes.
Download or read book Polymer Surfaces Interfaces And Thin Films written by Alamgir Karim and published by World Scientific Publishing Company. This book was released on 2000-04-19 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theoretical and experimental study of polymers, polymer surfaces and thin films has undergone a revolution in the last 25 years. This book captures recent advances in this field. It covers equilibrium aspects, kinetics and reactions at interfaces. It is aimed not only at a research audience but also at beginners.
Download or read book Glass Transition Dynamics and Heterogeneity of Polymer Thin Films written by Toshiji Kanaya and published by Springer. This book was released on 2012-12-15 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mobility Gradient of Polystyrene in Films Supported on Solid Substrates, by Yoshihisa Fujii, Hiroshi Morita, Atsushi Takahara and Keiji Tanaka Probing Properties of Polymers in Thin Films Via Dewetting, by Günter Reiter Heterogeneous and Aging Dynamics in Single and Stacked Thin Polymer Films, by Koji Fukao, Takehide Terasawa, Kenji Nakamura, Daisuke Tahara Heterogeneous Dynamics of Polymer Thin Films as Studied by Neutron Scattering, by Rintaro Inoue and Toshiji Kanaya
Download or read book Polymer Thin Films written by Ophelia Kwan Chui Tsui and published by World Scientific. This book was released on 2008 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ch. 1. Block copolymer thin films / J.-Y. Wang, S. Park and T. P. Russell -- ch. 2. Equilibration of block copolymer films on chemically patterned surfaces / G. S. W. Craig, H. Kang and P. F. Nealey -- ch. 3. Structure formation and evolution in confined cylinder-forming block copolymers / G. J. A. Sevink and J. G. E. M. Fraaije -- ch. 4. Block copolymer lithography for magnetic device fabrication / J. Y. Cheng and C. A. Ross -- ch. 5. Hierarchical structuring of polymer nanoparticles by self-organization / M. Shimomura ... [et al.] -- ch. 6. Wrinkling polymers for surface structure control and functionality / E. P. Chan and A. J. Crosby -- ch. 7. Crystallization in polymer thin films: morphology and growth / R. M. Van Horn and S. Z. D. Cheng -- ch. 8. Friction at soft polymer surface / M. K. Chaudhury, K. Vorvolakos and D. Malotky -- ch. 9. Relationship between molecular architecture, large-strain mechanical response and adhesive performance of model, block copolymer-based pressure sensitive adhesives / C. Creton and K. R. Shull -- ch. 10. Stability and dewetting of thin liquid films / K. Jacobs, R. Seemann and S. Herminghaus -- ch. 11. Anomalous dynamics of polymer Films / O. K. C. Tsui.
Download or read book Relaxation Behaviour of Patterned Composite Polymer Surfaces and Underlying Compensation Phenomenon written by Sonal Bhadauriya and published by . This book was released on 2019 with total page 219 pages. Available in PDF, EPUB and Kindle. Book excerpt: Imprinted polymer and polymer nanocomposite surfaces are ubiquitous in nature but how do such surfaces relax? What underlying fundamental mechanism governs the relaxation behaviour of such films? These are some of the pressing questions in the realm of flexible electronics, advanced lithography, nanodevices and biosensors where a decay in the stability of imprinted nanostructures can render them unusable. Therefore, tuning the stability of imprinted features in polymer thin films presents an important problem from both fundamental and application standpoint. The stability of imprinted nanostructures in homopolymer thin films has been extensively studied, using both ex-situ and in-situ procedures where the structural decay is governed by Laplace pressure induced viscous flow. Imprinted polymer nanocomposite films are ubiquitously present; from laminates to drag reducing coatings but the effect of additives in imparting structural stability is essentially unexplored.In the first section of this study, the nano-structure decay (also called "slumping") in imprinted PMMA thin films (≈ 100 nm) containing clustered PMMA grafted titania nanoparticles (TiO2 PGNP) and well-dispersed PMMA grafted Silica nanoparticles (SiO2 PGNP) was investigated. It was demonstrated that the stability of the nanoimprinted pattern at temperature above the matrix's glass transition temperature can be tuned by addition of these nanoparticles to the polymer matrix. This is the first experimental investigation of structural decay of a patterned nanocomposite film and it sheds light on an underlying entropy-enthalpy compensation (EEC) behaviour governing the decay process. EEC signifies a linear dependence between the activation parameters of the relaxation process and is routinely observed in the dynamics of many condensed materials such as molecular additives and glass-forming materials. Herein we found relaxation behaviour of nanoparticle filled imprinted polymer films illustrating similar compensation effect, which lead to slower decay kinetics of nanocomposite thin film above a certain compensation temperature compared to the neat polymer film. This characteristic temperature is conventionally called the entropy−enthalpy compensation (EEC) temperature, Tcomp and it was found to be ≈ 92 (±5) °C for TiO2 PGNP and 91 (±3) °C for SiO2 PGNP, a temperature in the vicinity of the matrix Tg ≈ 97 °C. An important implication of the compensation behaviour is that the stabilizing effect of the PGNP on the imprinted patterns should no longer exists if the slumping temperature is lower than Tcomp. It was seen that the filled imprinted pattern slumps more rapidly compared to the pure PMMA film at 80 °C (T
Download or read book Polymer Physics written by Leszek A. Utracki and published by John Wiley & Sons. This book was released on 2011-02-14 with total page 677 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing a comprehensive review of the state-of-the-art advanced research in the field, Polymer Physics explores the interrelationships among polymer structure, morphology, and physical and mechanical behavior. Featuring contributions from renowned experts, the book covers the basics of important areas in polymer physics while projecting into the future, making it a valuable resource for students and chemists, chemical engineers, materials scientists, and polymer scientists as well as professionals in related industries.
Download or read book Polymer Thin Films written by Ophelia Kwan Chui Tsui and published by World Scientific. This book was released on 2008 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymer thin films is an emerging area driven by their enormous technological potential and the intellectually challenging academic problems associated with them. This book contains a collection of review articles on the current topics of polymer films written by leading experts in the field. To reflect the interdisciplinary nature of this field, the contributors hail from a wide range of disciplines, including chemists, chemical engineers, materials scientists, engineers, and physicists. The goal of this book is to provide readers, whether involved in or outside of the field of polymer films, with an encompassing and informative reference.
Download or read book Structure and Properties of Polymer Films written by R. Lenz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the relationship between the structure, morphology and properties of polymer films has significantly progressed in recent years through the use of a number of phyiscal techniques - some new and some old. These methods include small and large angle x-ray diffraction, bire fringence, light scattering, infrared dichroism, fluorescence polarization, light and electron microscopy and interferrometry. This collection of papers, most of which were presented at a symposium at the Boston American Chemical Society Meeting in April, 1972, represent a collection of recent studies using many of these methods by some of the leading scientists in their fields. It is evident that these various techniques permit the study of various aspects of film structure such as crystal structure and orientation, amorphous orientation, the interrelation of crystalline and amorphous regions in lamellar, fibrillar, and spherulitic superstructure and the relationshi. p of these structural variables to the mechanical and optical properties of the films. Film structure is sufficiently complex that a complete understanding of the relationship between structure and properties will come from the employment of a combination of several of these methods. vii CONTENTS Optical Studies of the Morphology of Polymer Films ••• • • 1 Richard S. Stein Light Scattering by Oriented Native Cellulose Systems 25 R. H. Marchessault Superstructure in Films of Bio and Biorelated Small Angle Polymers as Noted by 39 Light Scattering • • Garth L.
Download or read book Mechanical Tribology written by George E. Totten and published by CRC Press. This book was released on 2004-04-22 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studying the morphology, defects, and wear behavior of a variety of material surfaces, Mechanical Tribology examines popular and emerging surface characterization techniques for assessment of the physical, mechanical, and chemical properties of various modified surfaces, thin films, and coatings. Its chapters explore a wide range of tribolo
Download or read book Probing the Distribution of Glass Transition Temperatures and Related Relaxation Behavior in Thin and Ultrathin Polymer Films Using Novel Fluorescence Approaches written by Christopher John Ellison and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presented here also stands as the first demonstration that the thickness dependence of Tg in nanoconfined single layer films may be significantly "tuned" via the addition of low molecular weight diluents or by small modifications to the repeat unit structure of PS. These surprising results may be explained by an alteration in the magnitude of the perturbation on Tg at the free surface and/or a reduction in the ability of interfacial effects to propagate into the film interior, which is argued to be related to the level of cooperativity of the polymer.
Download or read book Non equilibrium Phenomena in Confined Soft Matter written by Simone Napolitano and published by Springer. This book was released on 2015-08-28 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with those properties of non-equilibrium soft matter that deviate greatly from the bulk properties as a result of nanoscale confinement.The ultimate physical origin of these confinement effects is not yet fully understood. At the state of the art, the discussion on confinement effects focuses on equilibrium properties, finite size effects and interfacial interactions. However this is a limited vision which does not fully capture the peculiar behaviour of soft matter under confinement and some exotic phenomena that are displayed. This volume will be organized in the following three main themes. Equilibration and physical aging: treating non-equilibrium via the formal methodology of statistical physics in bulk, we analyse physical origin of the non-equilibrium character of thin polymer. We then focus on the impact of nanoconfinement on the equilibration of glasses of soft matter (a process of tremendous technological interest, commonly known as physical aging), comparing the latest trends of polymers in experiments, simulations with those of low-molecular weight glass formers. Irreversible adsorption: the formation of stable adsorbed layers occurs at timescales much larger than the time necessary to equilibrate soft matter in bulk. Recent experimental evidence show a strong correlation between the behaviour of polymers under confinement and the presence of a layer irreversibly adsorbed onto the substrate. This correlation hints at the possibility to tailor the properties of ultrathin films by controlling the adsorption kinetics. The book reports physical aspects of irreversible chain adsorption, such as the dynamics, structure, morphology, and crystallization of adsorbed layers. Glass transition and material properties: this section of the book focuses on the spread of absolute values in materials properties of confined systems, when measured by different experimental and computation techniques and a new method to quantify the effects of confinement in thin films and nanocomposites independently on the investigation procedure will be presented.
Download or read book Carbon Containing Polymer Composites written by Mostafizur Rahaman and published by Springer. This book was released on 2018-10-05 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the methods synthesizing various carbon materials, like graphite, carbon blacks, carbon fibers, carbon nanotubes, and graphene. It also details different functionalization and modification processes used to improve the properties of these materials and composites. From a geometrical–structural point of view, it examines different properties of the composites, such as mechanical, electrical, dielectric, thermal, rheological, morphological, spectroscopic, electronic, optical, and toxic, and describes the effects of carbon types and their geometrical structure on the properties and applications of composites.
Download or read book Dynamics in Geometrical Confinement written by Friedrich Kremer and published by Springer. This book was released on 2014-06-03 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the dynamics of low molecular weight and polymeric molecules when they are constrained under conditions of geometrical confinement. It covers geometrical confinement in different dimensionalities: (i) in nanometer thin layers or self supporting films (1-dimensional confinement) (ii) in pores or tubes with nanometric diameters (2-dimensional confinement) (iii) as micelles embedded in matrices (3-dimensional) or as nanodroplets. The dynamics under such conditions have been a much discussed and central topic in the focus of intense worldwide research activities within the last two decades. The present book discusses how the resulting molecular mobility is influenced by the subtle counterbalance between surface effects (typically slowing down molecular dynamics through attractive guest/host interactions) and confinement effects (typically increasing the mobility). It also explains how these influences can be modified and tuned, e.g. through appropriate surface coatings, film thicknesses or pore diameters. "Dynamics in Confinement" sums up the present state-of-the-art and introduces to the analytical methods of choice for the study of dynamics in nanometer-scale confinement.
