Thermal Degradation Of Polymeric Materials

Thermal Degradation of Polymeric Materials, Second Edition offers a wealth of information for polymer researchers and processors who require a thorough understanding of the implications of thermal degradation on materials and product performance. Sections cover thermal degradation mechanisms and kinetics, as well as various techniques, such as thermogravimetry in combination with mass spectroscopy and infrared spectrometry to investigate thermal decomposition routes. Other chapters focus on polymers and copolymers, including polyolefins, styrene polymers, polyvinyl chloride, polyamides, polyurethanes, polyesters, polyacrylates, natural polymers, inorganic polymers, high temperature-resistant and conducting polymers, blends, organic-inorganic hybrid materials, nanocomposites, and biocomposites. Finally, other key considerations such as recycling of polymers by thermal degradation, thermal degradation during processing, and modelling, are discussed in detail. Explains mechanisms of polymer degradation, making it possible to understand and predict material behavior at elevated temperatures Offers systematic coverage of each polymer group that is supported by data detailed explanations and critical analysis Investigates thermal decomposition routes in new materials, such as organic-inorganic hybrid materials and polymer nanocomposites

The contents have been divided into sections on physical states of polymers and characterization techniques. Chapters on physical states include discussions of the rubber elastic state, the glassy state, melts and concentrated solutions, the crystalline state, and the mesomorphic state. Characterization techniques described are molecular spectroscopy and scattering techniques.

The study of polymer degradation and stabilisation is of considerable practical importance as the industrial uses of polymeric materials continue to expand. In this book, the authors lucidly relate technological phenomena to the chemistry and physics of degradation and stabilisation processes. Degradation embraces a variety of technologically important phenomena ranging from relatively low temperature processes such as 'weathering' of plastics, 'fatigue' of rubbers through the processing of polymers in shearing mixers to very high temperature processes such as flammability and ablation. All these technological phenomena have in common certain basic chemical reactions. Thus 'weathering' has its roots in photo-oxidation, 'fatigue' and melt-degradation in mechano-oxidation and flammability, and ablation in ablation in pyrolysis and vapour phase oxidation.

The book is in five parts: Part I introduces the physical and chemical structure of polymers and their breakdown; Part II reviews electrical degradation in polymers, and Part III reviews conduction and deterministic breakdown in solids. Part IV discusses the stochastic nature of break-down from empirical and modelling viewpoints, and Part V indicates practical implications and strategies for engineers. Much of the discussion applies to non-crystalline materials generally.

The development of polymers as an important class of material was inhibited at the first by the premature failure of these versatile compounds in many applications. The deterioration of important properties of both natural and synthetic polymers is the result of irreversible changes in composition and structure of polymers molecules. As a result of these reactions, mechanical, electrical and/or aesthetic properties are degraded beyond acceptable limits. It is now generally recognized that stabilization against degradation is necessary if the useful life of polymers is to be extended sufficiently to meet design requirements for long-term applications. Polymers degrade by a wide variety of mechanisms, several of which affect all polymers through to varying degree. This monograph will concentrate on those degradation mechanisms which result from reactions of polymers with oxygen in its various forms and which are accelerated by heat and/or radiation. Those stabilization mechanisms are discussed which are based on an understanding of degradation reaction mechanisms that are reasonably well established. The stabilization of polymers is still undergoing a transition from an art to a science as mechanisms of degradation become more fully developed. A scientific approach to stabilization can only be approached when there is an understanding of the reactions that lead to degradation. Stabilization against biodegradation and burning will not be discussed since there is not a clear understanding of how polymers degrade under these conditions.

Thermal Characterization of Polymeric Materials is a critical review and a concise evaluation of the application of thermal analysis in polymer science and engineering. This book is divided into nine chapters that specifically tackle the instrumentation, theory, and a wide variety of applications of thermal characterization. The introductory chapters provide an overview of all aspects of thermal analytical methods and apparatus and the theory underlying the basic principles of thermal analysis. These chapters also examine the theories and functions of state for thermometry, dilatometry, thermomechanical analysis, calorimetry, thermogravimetry. These topics are followed by a discussion on single-component and multicomponent systems and their phase transitions, as influenced by concentration, pressure, deformation, molecular weight, and copolymerization. The subsequent chapters explore the influence of important chemical and physical parameters on the glass transition, crystallization, and melting of thermoplastic materials. The discussion then shifts to the theoretical aspects of polymer-polymer compatibility, phase separation, and miscibility in mixed polymer systems. This book further considers the thermal analysis in thermosets, elastomers, and fibers. The concluding chapters present the methods of obtaining information on the relative flammability properties of polymers, for screening fire retardant additives, and for studying the mechanism of flame inhibition. These chapters also look into the thermal analysis of antioxidants, stabilizers, lubricants, plasticizers, impact modifiers, and fire retardants. Polymer scientists and researchers will find this book invaluable.

Recycling of Polyurethane Foams introduces the main degradation/depolymerization processes and pathways of polyurethane foam materials, focusing on industrial case studies and academic reviews from recent research and development projects. The book can aid practitioners in understanding the basis of polymer degradation and its relationship with industrial processes, which can be of substantial value to industrial complexes the world over. The main pathways of polymer recycling via different routes and industrial schemes are detailed, covering all current techniques, including regrinding, rebinding, adhesive pressing and compression moulding of recovered PU materials that are then compared with depolymerization approaches. The book examines life cycle assessment and cost analysis associated with polyurethane foams waste management, showing the potential of various techniques. This book will help academics and researchers identify and improve on current depolymerization processes, and it will help industry sustainability professionals choose the appropriate approach for their own waste management systems, thus minimizing the costs and environmental impact of their PU-based end products. Offers a comprehensive review of all polyurethane foam recycling processes, including both chemical and mechanical approaches Assesses the potential of each recycling process Helps industry-based practitioners decide which approach to take to minimize the cost and environmental impact of their end product Enables academics and researchers to identify and improve upon current processes of degradation and depolymerization

This volume provides in-depth knowledge and recent research on polymers and nanostructured materials from synthesis to advanced applications. Leading researchers from industry, academia, government, and private research institutions across the globe have contributed to this volume, covering new research on nanocomposites, polymer technology, and electrochemistry.