Download or read book Single Molecule Studies of Diffusion Dynamics in Polymer Thin Films Near Tg written by Kewei Xu and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies of Single molecule Dynamics in Polymer Films written by Daniel Ray Bertram Sluss and published by . This book was released on 2009 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Fundamental Understanding of Physicochemical Properties of Ultra thin Polymer Films written by Annapoorani Sundaramoorthi and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Diffusion behavior of spin cast polymer thin films was studied in detail as a function of film thickness. Diffusion coefficients of water molecules in poly(methyl methacrylate) (PMMA) were found to decrease from 10-8 cm2/s in thick films to 10-13 cm2/s in ultra-thin films. In order to probe if there is a characteristic length scale set by the polymer chain size, the effect of PMMA molecular weights on this behavior was tested and deviation of diffusion coefficient from bulk was observed in all molecular weights of PMMA investigated. Diffusion coefficients in these films was also studied as a function of aging time at 25°C and was not found to change significantly over a time period of approximately four months. The impact of residual casting solvent in thick and thin films was studied and found to have no influence in the diffusion behavior. Positron Annihilation Lifetime Spectroscopy (PALs) was used to probe the free volume (FV) pocket size and its distribution within the film as a function of film thickness in PMMA. Decrease in FV pocket size was found to be one of the general underlying causes for such thickness dependent diffusion behavior observed in thin polymer films. In addition, Protracted Colored Noise Dynamics (PCND) that enables efficient sampling of phase space and faster relaxation of the systems compared to Molecular Dynamics (MD) was investigated for its extensibility to three dimensional systems and was found to be sensitive to initial conformation.
Download or read book Dynamics of Polymer Thin Films and Surfaces written by Zahra Fakhraai and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Molecular Dynamics Studies of the Diffusion of Adsorbed and Confined Polymer Films written by Debashish Mukherji and published by . This book was released on 2007 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Single Molecule Studies of Flexible Polymers Under Shear and Mixed Flows written by Rodrigo Esquivel Teixeira and published by . This book was released on 2005 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymer Science A Comprehensive Reference written by and published by Newnes. This book was released on 2012-12-05 with total page 7752 pages. Available in PDF, EPUB and Kindle. Book excerpt: The progress in polymer science is revealed in the chapters of Polymer Science: A Comprehensive Reference, Ten Volume Set. In Volume 1, this is reflected in the improved understanding of the properties of polymers in solution, in bulk and in confined situations such as in thin films. Volume 2 addresses new characterization techniques, such as high resolution optical microscopy, scanning probe microscopy and other procedures for surface and interface characterization. Volume 3 presents the great progress achieved in precise synthetic polymerization techniques for vinyl monomers to control macromolecular architecture: the development of metallocene and post-metallocene catalysis for olefin polymerization, new ionic polymerization procedures, and atom transfer radical polymerization, nitroxide mediated polymerization, and reversible addition-fragmentation chain transfer systems as the most often used controlled/living radical polymerization methods. Volume 4 is devoted to kinetics, mechanisms and applications of ring opening polymerization of heterocyclic monomers and cycloolefins (ROMP), as well as to various less common polymerization techniques. Polycondensation and non-chain polymerizations, including dendrimer synthesis and various "click" procedures, are covered in Volume 5. Volume 6 focuses on several aspects of controlled macromolecular architectures and soft nano-objects including hybrids and bioconjugates. Many of the achievements would have not been possible without new characterization techniques like AFM that allowed direct imaging of single molecules and nano-objects with a precision available only recently. An entirely new aspect in polymer science is based on the combination of bottom-up methods such as polymer synthesis and molecularly programmed self-assembly with top-down structuring such as lithography and surface templating, as presented in Volume 7. It encompasses polymer and nanoparticle assembly in bulk and under confined conditions or influenced by an external field, including thin films, inorganic-organic hybrids, or nanofibers. Volume 8 expands these concepts focusing on applications in advanced technologies, e.g. in electronic industry and centers on combination with top down approach and functional properties like conductivity. Another type of functionality that is of rapidly increasing importance in polymer science is introduced in volume 9. It deals with various aspects of polymers in biology and medicine, including the response of living cells and tissue to the contact with biofunctional particles and surfaces. The last volume is devoted to the scope and potential provided by environmentally benign and green polymers, as well as energy-related polymers. They discuss new technologies needed for a sustainable economy in our world of limited resources. Provides broad and in-depth coverage of all aspects of polymer science from synthesis/polymerization, properties, and characterization methods and techniques to nanostructures, sustainability and energy, and biomedical uses of polymers Provides a definitive source for those entering or researching in this area by integrating the multidisciplinary aspects of the science into one unique, up-to-date reference work Electronic version has complete cross-referencing and multi-media components Volume editors are world experts in their field (including a Nobel Prize winner)
Download or read book Ensemble and Single molecular Studies of Polymer Dynamics Near the Glass Transition written by Chia-Yin Wei and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Polymer Thin Films written by Ophelia K C Tsui and published by World Scientific. This book was released on 2008-11-21 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 Dynamical Heterogeneities in Glasses Colloids and Granular Media written by Ludovic Berthier and published by Oxford University Press. This book was released on 2011-07-14 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most everyday solid materials, from plastics to cosmetic gels, exist in a non-crystalline, amorphous form: they are glasses. Yet we are still seeking an explanation as to what glasses really are and to why they form. In this book, leading experts present broad and original perspectives on one of the deepest mysteries of condensed matter physics.
Download or read book Studies of Micro environments in Polymer and Silicate Thin Films by Single Molecule Spectroscopy written by Yanwen Hou and published by . This book was released on 2002 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mass Transport Properties in Thin Ion exchange Polymer Films and Related Phenomena written by Nebojsa Pantelic and published by . This book was released on 2007 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin ion-exchange polymer films (henceforth polyelectrolytes) have recently acquired substantial research interest. This is due in large part to the great promise demonstrated by the effective uptake and large preconcentration ratios of the ions from a liquid environment. The nanostructured porous film is an essential element of the spectroelectrochemical sensors. One fundamental aspect of the research involves molecular mass transport at the liquid/solid interface and associated film dynamics. These were studied using spectroscopic ellipsometry and quartz crystal microgravimetry and a good overall agreement between methods has been confirmed. The methodology for diffusion modeling was developed and demonstrated using several polyelectrolyte film materials. Three different theoretical models that account for non-ideal behaviors were employed to solve for the correct mechanism. Slow polymer relaxations coupled with ideal Fickian diffusion caused anomalies. The mass transport of model analytes was characterized by relatively slow diffusion constants (D = 10-12 - 10 -14 cm2/s) and relaxation rate constants (kR = 10-4 - 10-5 s-1). Anomalous diffusion in poly(vinyl alcohol)-poly(acrylic acid) (PVA-PAA) composite thin films and the structure-property relationship were studied in detail. The results of in situ complexation between Fe2+ and ligand (2,2'-bipyridine) in thin Nafion films gave important insight into the set of chemical reactions for aqueous iron detection. The last chapter focuses on dynamics of a novel polyelectrolyte film material for chemical sensing, namely, partially sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SSEBS). The physico-chemical phenomenon of molecular aggregation was studied using rhodamine 6G laser dye and the SSEBS film material. It was demonstrated for the first time how spectroscopic ellipsometry could be effectively used in studying such a subtle process in thin films. The two thesis appendices are devoted to surface studies. The ultra-thin polyelectrolyte films (5-12 nm) were imaged using atomic force microcopy (AFM) and the results revealed "island-like" structures. The luminescence quenching of the laser dyes at the semiconductor indium tin oxide (ITO) surfaces was demonstrated using evanescent wave spectroscopy. The results of investigation showed that within the first few nanometers from the ITO surface the luminescence was significantly reduced. In conclusion, the work gives important new insight into fundamental aspects of the spectroelectrochemical sensors.
Download or read book On Near free surface Dynamics of Thin Polymer Films written by Dongping Qi and published by . This book was released on 2009 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies show that dynamical properties of ultra-thin polymer films deviate from those of bulk materials. Despite some controversial issues, there is growing evidence indicating that the interfacial properties play a key role for observed dynamical anomalies. However, how and how much the interfacial properties affect the average dynamics of the nanometer scale systems are still elusive. In this work, we developed several novel techniques to investigate near-free-surface dynamics of thin polymer films. We studied surface dynamics of glassy i-PMMA films using a nano surface hole relaxation technique: a strong substrate property dependence and an unexpected molecular weight dependence were observed; we found that a local Tg of ~40K below bulk Tg could be assigned to the surface region. We used nano gold particle embedding to study PS surface dynamics: enhanced surface dynamics and weak temperature dependence were observed for the surface region; a depth profile with the nm resolution was observed; viscous liquid-like and soft solid-like properties were observed in the first 5.5nm and next 3.3 nm regions in PS films; no molecualr weight dependence was found in glassy PS films. We built a low level noise measurement system to study the thermal polarization noise in PVAc films: cooperative rearranging dynamics were evidenced; the noise power spectral density (PSD) is found to fluctuate around a certain average level without discernable peak shift; we observed some relatively big jumps or fluctuations in successive integrated PSD's, which indicate some energy exchange between different microscopic domains in glassy polymer systems. We developed a novel nano rheology AFM technique to study the near-free-surface dynamics of thin polymer films: enhanced near-free-surface dynamics with weak temperature dependence are observed for PVAc films, which is similar with the PS case.
Download or read book Theory and Modeling of Polymer Nanocomposites written by Valeriy V. Ginzburg and published by Springer Nature. This book was released on 2020-12-16 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: This edited volume brings together the state of the art in polymer nanocomposite theory and modeling, creating a roadmap for scientists and engineers seeking to design new advanced materials. The book opens with a review of molecular and mesoscale models predicting equilibrium and non-equilibrium nanoscale structure of hybrid materials as a function of composition and, especially, filler types. Subsequent chapters cover the methods and analyses used for describing the dynamics of nanocomposites and their mechanical and physical properties. Dedicated chapters present best practices for predicting materials properties of practical interest, including thermal and electrical conductivity, optical properties, barrier properties, and flammability. Each chapter is written by leading academic and industrial scientists working in each respective sub-field. The overview of modeling methodology combined with detailed examples of property predictions for specific systems will make this book useful for academic and industrial practitioners alike.
