Polymer Degradation and Stability Research Developments

Author: Leo B. Albertov
Publisher: Nova Science Pub Incorporated
ISBN: 9781600218279
Category: Science
Page: 315
View: 9602

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Polymer degradation is a change in the properties -- tensile strength, colour, shape, etc -- of a polymer or polymer based product under the influence of one or more environmental factors such as heat, light or chemicals. These changes may be undesirable, such as changes during use, or desirable, as in biodegradation or deliberately lowering the molecular weight of a polymer. Such changes occur primarily because of the effect of these factors on the chemical composition of the polymer. In a finished product such a change is to be prevented or delayed. However the degradation process can be useful from the view points of understanding the structure of a polymer or recycling/reusing the polymer waste to prevent or reduce environmental pollution. Polymer molecules are very large on the molecular scale which derive their unique and useful properties from their size. This book presents leading-edge research in the field.

Progress in Polymer Degradation and Stability Research

Author: Herbert W. Moeller
Publisher: Nova Publishers
ISBN: 9781600218286
Category: Science
Page: 390
View: 9043

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Polymer degradation is a change in the properties - tensile strength, colour, shape, etc - of a polymer or polymer based product under the influence of one or more environmental factors such as heat, light or chemicals. These changes may be undesirable, such as changes during use, or desirable, as in biodegradation or deliberately lowering the molecular weight of a polymer. Such changes occur primarily because of the effect of these factors on the chemical composition of the polymer. In a finished product such a change is to be prevented or delayed. However, the degradation process can be useful from the view points of understanding the structure of a polymer or recycling/reusing the polymer waste to prevent or reduce environmental pollution. Polymers molecules are very large on the molecular scale which derive their unique and useful properties from their size.

Stability and Degradation of Organic and Polymer Solar Cells

Author: Frederik C. Krebs
Publisher: John Wiley & Sons
ISBN: 1118312236
Category: Technology & Engineering
Page: 368
View: 7045

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Organic photovoltaics (OPV) are a new generation of solar cells with the potential to offer very short energy pay back times, mechanical flexibility and significantly lower production costs compared to traditional crystalline photovoltaic systems. A weakness of OPV is their comparative instability during operation and this is a critical area of research towards the successful development and commercialization of these 3rd generation solar cells. Covering both small molecule and polymer solar cells, Stability and Degradation of Organic and Polymer Solar Cells summarizes the state of the art understanding of stability and provides a detailed analysis of the mechanisms by which degradation occurs. Following an introductory chapter which compares different photovoltaic technologies, the book focuses on OPV degradation, discussing the origin and characterization of the instability and describing measures for extending the duration of operation. Topics covered include: Chemical and physical probes for studying degradation Imaging techniques Photochemical stability of OPV materials Degradation mechanisms Testing methods Barrier technology and applications Stability and Degradation of Organic and Polymer Solar Cells is an essential reference source for researchers in academia and industry, engineers and manufacturers working on OPV design, development and implementation.

Biodegradable Polymer Blends and Composites from Renewable Resources

Author: Long Yu
Publisher: John Wiley & Sons
ISBN: 0470391553
Category: Technology & Engineering
Page: 400
View: 6467

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Biodegradable Polymer Blends and Composites from Renewable Resources provides a comprehensive, current overview of biopolymeric blends and composites and their applications in various industries. The book is organized according to the type of blend or composite. For each topic, the relationship between the structure of the blends/composites and their respective properties is explored, with particular focus on interface, compatibility, mechanical, and thermal properties. Real-life applications and potential markets are discussed. This is a premier reference for graduate students and researchers in polymer science, chemical and bio engineering, and materials science.

Handbook of UV Degradation and Stabilization

Author: George Wypych
Publisher: Elsevier
ISBN: 1927885019
Category: Technology & Engineering
Page: 430
View: 6977

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This book, the second edition of the first monograph fully devoted to UV degradation and stabilization ever published in English, has 12 chapters discussing different aspects of UV related phenomena occurring when polymeric materials are exposed to UV radiation. In the introduction the existing literature has been reviewed to find out how plants, animals and humans protect themselves against UV radiation. This review permits evaluation of mechanisms of protection against UV used by living things and potential application of these mechanisms in protection of natural and synthetic polymeric materials. This is followed by chapters with a more detailed look at more specific aspects of UV degradation and stabilization. A practical and up-to-date reference guide for engineers and scientists designing with plastics, and formulating plastics materials Explains the effects of UV light on plastics, and how to mitigate its effects through the use of UV stabilizers Surveys the range of UV stabilizers on the market, and provides advice on their selection and use

Nanostructured Polymer Blends

Chapter 1. Polymer Blends
Author: Chandran C. Sarath,Robert A. Shanks,S. Thomas
Publisher: Elsevier Inc. Chapters
ISBN: 0128090782
Category: Technology & Engineering
Page: 576
View: 6903

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Miscibility and compatibility in polymer blends is a topic of great academic and industrial importance. This is because miscibility and compatibility contribute to morphology, properties, and performance. Miscibility results in one phase; compatibility creates a disperse phase with size and stability determined by interfacial interactions. Miscible polymer properties are averaged similar to a plasticizer polymer, and compatible polymers retain properties of each component, such as toughening or reinforcement. With miscible polymer blends the continuous phase dominates properties; the disperse phase contributes via stress transfer. This chapter revisits the criteria for miscibility or compatibility in polymer blends and the contributors of compatibility compared with miscibility and incompatibility. Development of copolymers and their blending with thermosets and thermoplastics result in complex two-phase morphologies. The dynamics of phase separation observed in polymer blends leading to different morphologies and the criteria for phase separation is explained. A nanometer-dispersed phase requires strong interfacial interactions to stabilize the large interfacial area, and this is favored by rapid spinodal phase separation compared with size diminution by high shear. Nanoblends open up a new arena for polymer blends, and research shows that nanoblends have outstanding optical and mechanical properties.

PVC Degradation and Stabilization

Author: George Wypych
Publisher: Elsevier
ISBN: 1927885000
Category: Technology & Engineering
Page: 500
View: 2140

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PVC stabilization, the most important aspect of formulation and performance of this polymer, is discussed in details. This book contains all information required to design successful stabilization formula for any product made out of PVC. Separate chapters review information on chemical structure, PVC manufacturing technology, morphology, degradation by thermal energy, UV, gamma, other forms of radiation, mechanodegradation, and chemical degradation. The chapter on analytical methods used in studying of degradative and stabilization processes helps in establishing system of checking results of stabilization with different stabilizing systems. Stabilization and stabilizers are discussed in full detail in the most important chapter of this book. The final chapter contains information on the effects of PVC and its additives on health, safety and environment. This book contains analysis of all essential papers and patents published until recently on the above subject. It either locates the answers to relevant questions and offers solutions or gives references in which such answers can be found. PVC Degradation and Stabilization is must to have for chemists, engineers, scientists, university teachers and students, designers, material scientists, environmental chemists, and lawyers who work with polyvinyl chloride and its additives or have any interest in these products. This book is the one authoritative source on the subject. A practical and up-to-date reference guide for engineers and scientists designing with PVC Covers thermal, UV, gamma radiation, chemical, and other forms of degradation Includes a critical discussion of the sustainability issues faced by PVC and its additives, as well as health and safety concerns

Accelerated Aging

Photochemical and Thermal Aspects
Author: Robert L. Feller
Publisher: Getty Publications
ISBN: 0892361255
Category: Art
Page: 296
View: 4908

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Accelerated Aging: Photochemical and Thermal Aspects represents the culmination of more than 40 years of research by noted scientist Robert L. Feller. The book focuses on the long-term performance of materials such as wool, dyes, and organic compounds; their resistance to change when exposed to environmental factors such as oxygen, ozone, moisture, heat, and light; and their physical durability with handling and use over time. Processes of deterioration are discussed based on speeded-up laboratory studies designed to clarify the chemical reactions involved and their physical consequences.

Polymer Modifiers and Additives

Author: Richard F. Grossman,John T. Lutz Jr.
Publisher: CRC Press
ISBN: 1482273756
Category: Technology & Engineering
Page: 536
View: 1545

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"Outlines the benefits of using additives-individually or in combination-to modify the properties and processability of pure polymers, and discusses easy-to-understand theory and practical applications for immediate economic and performance improvements."

Handbook of Polymers

Author: George Wypych
Publisher: Elsevier
ISBN: 1927885116
Category: Technology & Engineering
Page: 712
View: 6828

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Handbook of Polymers, Second Edition, presents normalized, up-to-date polymer data in a consistent and easily referenceable layout. This new edition represents an update of the available data, including new values for many commercially available products, verification of existing data, and removal of older data where it is no longer useful. The book includes data on all major polymeric materials used by the plastics industry and all branches of the chemical industry, as well as specialty polymers used in the electronics, pharmaceutical, medical, and space fields. The entire scope of the data is divided into sections to make data comparison and search easy, including synthesis, physical, mechanical, and rheological properties, chemical resistance, toxicity and environmental impact, and more. The data enables engineers and materials scientists to solve practical problems, be that in applications, research and development, or legislation. The most current grades of materials have been selected to provide readers with information that is characteristic of currently available products. Includes practical data on the most widely used polymers for engineers and materials scientists in design, manufacture, and applications research Presents data on polymer synthesis, properties, chemical resistance, processing, and their related environmental impacts Provides a comprehensive update to the data, including new information and the verification of existing datasets

Photochemistry and Photophysics of Polymeric Materials

Author: Norman S. Allen
Publisher: John Wiley & Sons
ISBN: 0470594160
Category: Technology & Engineering
Page: 600
View: 3893

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Presents the state of the technology, from fundamentals to new materials and applications Today's electronic devices, computers, solar cells, printing, imaging, copying, and recording technology, to name a few, all owe a debt to our growing understanding of the photophysics and photochemistry of polymeric materials. This book draws together, analyzes, and presents our current understanding of polymer photochemistry and photophysics. In addition to exploring materials, mechanisms, processes, and properties, the handbook also highlights the latest applications in the field and points to new developments on the horizon. Photochemistry and Photophysics of Polymer Materials is divided into seventeen chapters, including: Optical and luminescent properties and applications of metal complex-based polymers Photoinitiators for free radical polymerization reactions Photovoltaic polymer materials Photoimaging and lithographic processes in polymers Photostabilization of polymer materials Photodegradation processes in polymeric materials Each chapter, written by one or more leading experts and pioneers in the field, incorporates all the latest findings and developments as well as the authors' own personal insights and perspectives. References guide readers to the literature for further investigation of individual topics. Together, the contributions represent a series of major developments in the polymer world in which light and its energy have been put to valuable use. Not only does this reference capture our current state of knowledge, but it also provides the foundation for new research and the development of new materials and new applications.

Pharmaceutical Stress Testing

Predicting Drug Degradation, Second Edition
Author: Steven W. Baertschi,Karen M. Alsante,Robert A. Reed
Publisher: CRC Press
ISBN: 1439801800
Category: Medical
Page: 612
View: 1954

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The second edition of Pharmaceutical Stress Testing: Predicting Drug Degradation provides a practical and scientific guide to designing, executing and interpreting stress testing studies for drug substance and drug product. This is the only guide available to tackle this subject in-depth. The Second Edition expands coverage from chemical stability into the physical aspects of stress testing, and incorporates the concept of Quality by Design into the stress testing construct / framework. It has been revised and expanded to include chapters on large molecules, such as proteins and antibodies, and it outlines the changes in stress testing that have emerged in recent years. Key features include: A renowned Editorial team and contributions from all major drug companies, reflecting a wealth of experience. 10 new chapters, including Stress Testing and its relationship to the assessment of potential genotoxic degradants, combination drug therapies, proteins, oligonucleotides, physical changes and alternative dosage forms such as liposomal formulations Updated methodologies for predicting drug stability and degradation pathways Best practice models to follow An expanded Frequently Asked Questions section This is an essential reference book for Pharmaceutical Scientists and those working in Quality Assurance and Drug Development (analytical sciences, formulations, chemical process, project management).

Mechanisms of Polymer Degradation and Stabilisation

Author: G. Scott
Publisher: Springer Science & Business Media
ISBN: 9401138389
Category: Technology & Engineering
Page: 329
View: 9964

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The purpose of this publication is two-fold. In the first place it is intended to review progress in the development of practical stabilising systems for a wide range of polymers and applications. A complemen tary and ultimately more important objective is to accommodate these practical developments within the framework of antioxidant theory, since there can be little question that further major advances in the practice of stabilisation technology will only be possible on a firm mechanistic foundation. With the continual increase in the number of commercial anti oxidants and stabilisers, often functioning by mechanisms not even considered ten years ago, there is a need for a general theory which will allow the potential user to predict the performance of a particular antioxidant structure under specific practical conditions. Any such predictive tool must involve a simplified kinetic approach to inhibited oxidation and, in Chapter 1, Denisov outlines a possible mechanistic approach with the potential to predict the most useful antioxidant to use and the limits of its usefulness. In Chapter 2, Schwetlick reviews the current state of knowledge on the antioxidant mechanisms of the phosphite esters with particular emphasis on their catalytic peroxidolytic activity. Dithiophosphate v vi PREFACE derivatives show a similar behaviour but for quite different reasons and, in Chapter 3, AI-Malaika reviews information available from analytical studies, particularly using 31p_NMR spectroscopy, to elucid ate the complex chemistry that leads to the formation of the antioxidant -active agents.

Thermally Stable and Flame Retardant Polymer Nanocomposites

Author: Vikas Mittal
Publisher: Cambridge University Press
ISBN: 1139495984
Category: Technology & Engineering
Page: N.A
View: 9794

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Polymer nanocomposites have revolutionised material performance, most notably in the plastics, automotive and aerospace industries. However, in order to be commercially viable, many of these materials must withstand high temperatures. In this book, leaders in the field outline the mechanisms behind the generation of suitable polymer systems, pulling together recent research to provide a unified and up-to-date assessment of recent technological advancements. The text is divided into two clear sections, introducing the reader to the two most important requirements for this material type: thermal stability and flame retardancy. Special attention is paid to practical examples, walking the reader through the numerous commercial applications of thermally stable and flame retardant nanocomposites. With a strong focus on placing theory within commercial context, this unique volume will appeal to practitioners as well as researchers.

Polymer Science and Engineering

The Shifting Research Frontiers
Author: N.A
Publisher: National Academies
Category: Science
Page: 180
View: 5000

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Polymers are used in everything from nylon stockings to commercial aircraft to artificial heart valves, and they play a key role in addressing environmental problems, international competitiveness, and other national issues. This book explores the universe of polymers in such fields as medicine and biotechnology information and communication, housing and construction, energy and transportation, national defense, and environmental protection. The committee looks at the various classes of polymers and how their composition and specific methods of processing result in unparalleled usefulness.

Thermo-oxidative Degradation of Polymers

Author: Thomas Roy Crompton
Publisher: Smithers Rapra Technology
ISBN: 9781847354723
Category: Science
Page: 136
View: 738

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The oxidative and thermal degradation of polymers has very important implications on their suitability for particular end-user applications. Particularly in relation to their physical properties and the lifetime over which the manufactured article retains these properties, after which they become unsuitable for purpose. Particular applications which come to mind are critical applications of polymers to the manufacture of electronic components and the design of polymeric alloys for aircraft fuselage assembly which retain their properties for many years over which the alloy must retain the physical properties at high or low operating temperatures. A particular area of growing importance is the recycling of manufactured components for re-use. Here, the polymer must retain its thermo oxidative resistance properties over a number of remouldings. A wide and increasing range of types of polymers are being used in these critical applications and an understanding of thermo oxidative processes will be very important in developing new applications in the future. This book brings together information on the thermooxidative resistance of polymers to change during processing and end-use life. Our present understanding of the chemical changes of the polymer that accompany degradation are also reviewed and the analytical methods by which changes can be ascertained are also discussed. This book will be of interest to those involved in the investigation of polymer stability and studies of the mechanics of polymer degradation, to polymer manufacturers and those who use polymers to manufacture end-use articles. This book will also be of interest to those involved in the manufacture of stabilisers for oxidation resistance for use in polymer manufacture, mechanical engineers and designers of polymer products.

Handbook of Stability Testing in Pharmaceutical Development

Regulations, Methodologies, and Best Practices
Author: Kim Huynh-Ba
Publisher: Springer Science & Business Media
ISBN: 0387856277
Category: Medical
Page: 389
View: 4411

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This handbook is the first to cover all aspects of stability testing in pharmaceutical development. Written by a group of international experts, the book presents a scientific understanding of regulations and balances methodologies and best practices.

Reactive Processing of Polymers

Author: M.W.R. Brown,A. F. Johnson,P. D. Coates
Publisher: iSmithers Rapra Publishing
ISBN: 9781859570111
Category: Information science
Page: 136
View: 435

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Developments in machinery, materials and applications are outlined in the cond104 of commercial considerations and advances in fundamental understanding. The principles and benefits of polymer modification and blending via reactive extrusion are explained. A b257 of novel techniques which have developed out of the major reactive processes are also described. An additional indexed section containing several hundred abstracts from the Rapra Polymer Library database provides useful references for further reading.

Properties of Polymers

Author: D.W. van Krevelen
Publisher: Elsevier
ISBN: 0444596127
Category: Technology & Engineering
Page: 898
View: 3080

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Properties of Polymers: Their Correlation with Chemical Structure; Their Numerical Estimation and Prediction from Additive Group Contributions summarizes the latest developments regarding polymers, their properties in relation to chemical structure, and methods for estimating and predicting numerical properties from chemical structure. In particular, it examines polymer electrical properties, magnetic properties, and mechanical properties, as well as their crystallization and environmental behavior and failure. The rheological properties of polymer melts and polymer solutions are also considered. Organized into seven parts encompassing 27 chapters, this book begins with an overview of polymer science and engineering, including the typology of polymers and their properties. It then turns to a discussion of thermophysical properties, from transition temperatures to volumetric and calorimetric properties, along with the cohesive aspects and conformation statistics. It also introduces the reader to the behavior of polymers in electromagnetic and mechanical fields of force. The book covers the quantities that influence the transport of heat, momentum, and matter, particularly heat conductivity, viscosity, and diffusivity; properties that control the chemical stability and breakdown of polymers; and polymer properties as an integral concept, with emphasis on processing and product properties. Readers will find tables that give valuable (numerical) data on polymers and include a survey of the group contributions (increments) of almost every additive function considered. This book is a valuable resource for anyone working on practical problems in the field of polymers, including organic chemists, chemical engineers, polymer processers, polymer technologists, and both graduate and PhD students.

Research Developments in Wood Engineering and Technology

Author: Aguilera, Alfredo
Publisher: IGI Global
ISBN: 1466645555
Category: Technology & Engineering
Page: 410
View: 8776

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"This book examines the latest research advances and technological developments for wood material as an engineering product and the innovation it provides for environmental friendly materials"--Provided by publisher.