Download or read book Yield and Relaxation in Polymeric Glasses written by Robert Howard Beck and published by . This book was released on 1971 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Understand the Mechanical Behaviors of Polymer Glasses Under Extension and Compression written by Jianning Liu and published by . This book was released on 2018 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: "It is of great fundamental important and practical interest to understand what controls the mechanical properties of polymeric glasses, such as shear yielding, necking, crazing, strain hardening and the brittle-ductile transition. Despite the tremendous efforts in the past decades to explorer the mechanical instabilities of polymer glasses, many topics about the nature of glass transition, nature of stress remain vague and under extensive debates. In this dissertation, we carried out a series of mechanical tests to study the mechanical response of polymeric glasses in both uniaxial extension and compression. Based on our recent phenomenological molecular model, this work investigates the origin of mechanical stress based on stress relaxation and brittle-ductile transition experiments of polymer glasses. Different from previous models emphasizing the inter-segmental contribution in stress, our stress relaxation experimental results revealed the important role of chain network by intra-chain connectivity and chain uncrossability. In Capture III, in room temperature stress relaxation experiments, we studied the stress relaxation behaviors of four different commercial polymer glasses under both extension and compression large ductile deformation over a wide range of rate. It was found that the initial stress relaxation rate after holding post-yield deformation is linearly proportional to the rate of prior deformation. While the pre-yield stress relaxation is logarithmically slow. This rate rescaling behaviors indicates the surviving segmental mobility in absence of ongoing deformation was due to the yield induced activation process. In Capture IV, to elucidate the nature of stress during deformation and stress relaxation, temperature for stress relaxation was increased to near Tg. All the pre-yield stress would vanish within fast segmental relaxation time independent of rate, while the initial post-yield stress relaxation can be either faster or far slower than the segmental dynamics dependents on prior deformation rate. Residual stress after large post-yield relaxation was observed to retain significant levels on the time scale much longer than the time scale for all the rate range investigated near Tg. Supporting results by MD simulation shown the chain network is essential in the mechanical response of uniaxial compression of glassy polymers through the chain network's lateral resistance to the lateral expansion and contribute to compressive stress. In Capture V and VI, to understand the role of chain network under uniaxial compression, we systematically studied how the structural change of chain network dictates whether the uniaxial compression of polymer glasses is ductile or suffers brittle fracture. Those structural characteristics of the perceived chain network can be changed by variation of molecular weight, molecular composition, and anisotropic reconstruction through melt stretching"--Website of ETD."
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 Stress Relaxation Behavior of Polymer Glasses in Both Extension and Compression written by Jianning Liu and published by . This book was released on 2015 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work investigates the origin of mechanical stress based on stress relaxation experiments of ductile and brittle polymer glasses. To learn more about the relaxation behavior of polymer glasses, a series of stress relaxation experiments in both extension and compression were carried out in pre-yield and post-yield regimes respectively. Tensile tests were carried out using ductile glasses such as bisphenol A polycarbonate (PC), and compression tests were performed based on brittle poly(methyl methacrylate) (PMMA) as well as PC. The stress relaxation is shown to speed up in linear proportion to the deformation rate in the post-yield regime. Such scaling behavior complements the in situ measurements of mobility as a function of the applied extensional rate1. Rate effect, strain effect and temperature effect were investigated. We studied how the relaxation dynamics depend on the prior deformation history, and delineate the results in term of our recently-proposed molecular model2.
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 573 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 Structure and Motion in Polymer Glasses written by and published by . This book was released on 1980 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Physics of Glassy Polymers written by R.N. Haward and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 513 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the publication of the first edition of The Physics of Glassy Polymers there have been substantial developments in both the theory and application of polymer physics, and many new materials have been introduced. Furthermore, in this large and growing field of knowledge, glassy polymers are of particular interest because of their homogeneous structure, which is fundamentally simpler than that of crystalline or reinforced materials. This new edition covers all these developments, including the emergence of the polymer molecule with its multiplicity of structure and conformations as the major factor controlling the properties of glassy polymers, using the combined knowledge of a distinguished team of contributors. With an introductory chapter covering the established science in the subject are and summarising concepts assumed in the later chapters, this fully revised and updated second edition is an essential work of reference for those involved in the field.
Download or read book Relaxation in Physical and Mechanical Behavior of Polymers written by Maxim Arzhakov and published by CRC Press. This book was released on 2019-01-30 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explores the nature of relaxation phenomena in polymers on the basis of time-temperature equivalence. Its role in the physical and mechanical behavior of polymers materials and fundamentals of thermoplastics processing are discussed. Four appendixes detail thermo-mechanical methods to study relaxation in polymers, structure of both amorphous and semi-crystalline polymers, and unified approach to describe deformation of polymeric materials.
Download or read book Molecular Mobility in Deforming Polymer Glasses written by Nikhil Padhye and published by Springer Nature. This book was released on 2021-10-15 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book bridges disparate fields in an exploration of the phenomena and applications surrounding molecular mobility in glassy materials experiencing inelastic deformation. The subjects of plastic deformation and polymer motion/interdiffusion currently belong to the two different fields of continuum mechanics and polymer physics, respectively. However, molecular motion associated with plastic deformation is a key ingredient to gain fundamental understanding, both at the macroscopic and microscopic level. This short monograph provides necessary background in the aforementioned fields before addressing the topic of molecular mobility accompanied by macroscopic inelastic deformation in an accessible and easy-to-understand manner. A new phenomenon of solid-state deformation-induced bonding in polymers is discussed in detail, along with some broad implications in several manufacturing sectors. Open questions pertaining to mechanisms, mechanics, and modeling of deformation-induced bonding in polymers are presented. The book’s clear language and careful explanations will speak to readers of diverse backgrounds.
Download or read book The Physics of Glassy Polymers written by R.N. Haward and published by Springer Science & Business Media. This book was released on 1997-10-31 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the publication of the first edition of The Physics of Glassy Polymers there have been substantial developments in both the theory and application of polymer physics, and many new materials have been introduced. Furthermore, in this large and growing field of knowledge, glassy polymers are of particular interest because of their homogeneous structure, which is fundamentally simpler than that of crystalline or reinforced materials. This new edition covers all these developments, including the emergence of the polymer molecule with its multiplicity of structure and conformations as the major factor controlling the properties of glassy polymers, using the combined knowledge of a distinguished team of contributors. With an introductory chapter covering the established science in the subject are and summarising concepts assumed in the later chapters, this fully revised and updated second edition is an essential work of reference for those involved in the field.
Download or read book Long Term Durability of Polymeric Matrix Composites written by Kishore V. Pochiraju and published by Springer Science & Business Media. This book was released on 2011-09-25 with total page 681 pages. Available in PDF, EPUB and Kindle. Book excerpt: Long-Term Durability of Polymeric Matrix Composites presents a comprehensive knowledge-set of matrix, fiber and interphase behavior under long-term aging conditions, theoretical modeling and experimental methods. This book covers long-term constituent behavior, predictive methodologies, experimental validation and design practice. Readers will also find a discussion of various applications, including aging air craft structures, aging civil infrastructure, in addition to engines and high temperature applications.
Download or read book Group Interaction Modelling of Polymer Properties written by David Porter and published by CRC Press. This book was released on 1995-02-08 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes a consistent set of relations between the structure of polymers and their commercially important thermal and mechanical properties for engineering applications--facilitating the development of a framework of polymer physics to explore new application areas without prior correlations. Includes methods for the easy calculation of input parameters and tabulates the most important parameters for 250 polymers.
Download or read book Polymer Yearbook 16 written by Richard A. Pethrick and published by CRC Press. This book was released on 1999-06-23 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymer Yearbooks provide reviews of Japanese and Russian polymer science not otherwise readily available in English. An essential desk reference of general interest to polymer scientists, they contain reviews covering topics in polymer synthesis, degradation, renewable polymer sources, drug release, thermodynamics of polymers under shear, etc. The books also contain lists of recent publications in polymer science and a compilation of dissertation abstracts. Names and addresses of research annuals in polymer science and their editors are listed, together with useful information such as standard abbreviations and trade names. Containing summaries of useful physical, chemical, and mathematical data along with definitions of terms in polymer science, the Polymer Yearbook is a must for any practicing polymer chemist.This volume also contains reviews on state-of-the-art Japanese research presented in the annual Spring and Fall meetings of the Japanese Polymer Science Society. The aim of this section is to make information on the progress of Japanese polymer science, and on topics of current interest to polymer scientists in Japan, more easily available worldwide.
Download or read book Surface Phenomena in the Structural and Mechanical Behaviour of Solid Polymers written by L. Volynskii and published by CRC Press. This book was released on 2018-09-03 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface Phenomena in the Structural and Mechanical Behaviour of Solid Polymers explores the role of various surface phenomena in the structural and mechanical behaviour of amorphous and semicrystalline polymers. This book: Discusses the development of the interfacial surface in the deformation of polymers Examines the healing of interfacial surfaces in polymers Inspects the structure and properties of polymers in thin films and surface layers Evaluates the mechanism of inelastic deformation in glassy amorphous polymers Investigates strain softening and the phenomena taking place upon deformation of polymers in active liquid media Covers the Rehbinder effect, or the adsorption reduction of the strength of solids Describes the properties of polymers in environmental or solvent crazing Analyses the interaction of the highly developed surface of crazed polymers with diverse low- and high-molecular mass components Addresses the instability and self-organisation of surface layers in polymers and diverse polymer systems Presents theoretical speculations concerning the structurally mechanical behaviour of ‘a rigid coating on a soft substratum’ (RCSS) systems Assesses the stress–strain properties of the thin surface layers of polymers and the nanometric coatings deposited on their surfaces Highlights the efficacy of the approaches developed for RCSS systems for the analysis and description of natural phenomena Details the applied aspects of surface phenomena in the structurally mechanical behaviour of polymers Thus, Surface Phenomena in the Structural and Mechanical Behaviour of Solid Polymers provides a useful framework for the development of new and innovative polymer-based materials.
Download or read book Comparing Linear Stress Relaxation and Fluorescence Recovery written by Joshua V. Ricci and published by . This book was released on 2019 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Segmental dynamics of polymer glasses are monitored during physical aging via two experimental techniques: fluorescence recovery after photobleaching (FRAP), and linear stress relaxation. Three polymer systems, poly (methyl methacrylate) (PMMA), Poly(lactic acid) (PLA), and crosslinked PMMA are studied. For all systems, the fluorescent probe N,N'-Dipentyl-3,4,9,10-perylenedicarboximide (DPPC) is dilutely dispersed within the samples. FRAP and stress relaxation measurements are performed using a custom-built instrument to allow measurements of both stress and emitted fluorescence. The FRAP technique is uniquely capable of measurements of segmental dynamics in polymer glasses during large scale deformation of the sample, while linear stress relaxation is a straightforward and commonly applied technique, but can only be employed for small deformations that produce a linear mechanical response. The work presented here describes the comparison of results obtained from the two techniques across the three polymer systems examined. Both techniques are utilized to measure segmental dynamics in crosslinked PMMA during physical aging, at temperatures between 9 and 24 K below T[subscript g]. The relaxation times observed from the two sets of experiments are closely correlated, showing a power law relationship with an exponent of 1.11 across the temperature range. Relaxation times from FRAP experiments are a factor of ~2 larger than those observed from stress relaxation experiments, which is attributed to the large probe size relative to the segment size of PMMA. Similar experiments are performed on linear PMMA and PLA. Comparing results from the three polymer systems demonstrates the effects of crosslinking, water content, and the presence of a secondary relaxation process upon the measured dynamics. These features are shown to affect the observations from the two techniques to the same extent. In linear PMMA, the power law relationship between the results from the two techniques is the same as that observed in the crosslinked system. A power law relationship is also observed in PLA, with an exponent of 0.83. Taken as a whole, these experiments indicate that FRAP and linear stress relaxation measurements provide substantially the same information on the segmental dynamics, and support the use of FRAP experiments under conditions where no other techniques can provide quantitative information.
Download or read book Synthesis and Properties of Polymers written by Gennadiĭ Efremovich Zaikov and published by Nova Publishers. This book was released on 1996 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synthesis & Properties Of Polymers
Download or read book Fractal Mechanics of Polymers written by G. V. Kozlov and published by CRC Press. This book was released on 2014-11-12 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new book explores the consideration of relationships that connect the structural and basic mechanical properties of polymeric mediums within the frameworks of fractal analysis with cluster model representations attraction. Incidentally, the choice of any structural model of medium or their combinations is defined by expediency and further usag
