Polymer Processing with Supercritical Fluids


Book Description

SCFs are currently the subjects of intense research and commercial interest. Applications such as the RESS (rapid expansion of supercritical fluid solutions) process are part of standard industrial practice. In view of their ever-growing importance in the polymer industry there is a need to fully comprehend how supercritical fluids interrelate with polymeric materials to realise the potential that can be gained from their use. The authors review the basic principles of SCFs and their application within the polymer industry: characteristics and properties, extraction of unwanted residual products, polymerisation solvents, and polymer impregnation. Processing applications such as plasticisation, foaming and blending are also considered. There is discussion of the potential within the polymer recycling industry for use of SCFs as cleaning agents or within supercritical oxidation processes. Around 400 references with abstracts from recent global literature accompany this review, sourced from the Polymer Library, to facilitate further reading. A subject index and a company index are included.




Supercritical Carbon Dioxide


Book Description

Recently, supercritical fluids have emerged as more sustainable alternatives for the organic solvents often used in polymer processes. This is the first book emphasizing the potential of supercritical carbon dioxide for polymer processes from an engineering point of view. It develops a state-of-the-art overview on polymer fundamentals, polymerization reactions and polymer processing in supercritical carbon dioxide. The book covers topics in a multidisciplinary approach starting from polymer chemistry and thermodynamics, going through monitoring, polymerization processes and ending with polymer shaping and post-processing. The authors are internationally recognized experts from different fields in polymer reaction engineering in supercritical fluids. The book was initiated by the Working Party on Polymer Reaction Engineering of the European Federation of Chemical Engineering and further renowned international experts.




Supercritical Fluids


Book Description

Supercritical fluids are neither gas nor liquid, but can be compressed gradually from low to high density and they are therefore interesting and important as tunable solvents and reaction media in the chemical process industry. By adjusting the density the properties of these fluids can be customised and manipulated for a given process - physical or chemical transformation. Separation and processing using supercritical solvents such as CO2 are currently on-line commercially in the food, essential oils and polymer industries. Many agencies and industries are considering the use of supercritical water for waste remediation. Supercritical fluid chromatography represents another, major analytical application. Significant advances have recently been made in materials processing, ranging from particle formation to the creation of porous materials. The chapters in this book provide tutorial accounts of topical areas centred around: (1) phase equilibria, thermodynamics and equations of state; (2) critical behaviour, crossover effects; (3) transport and interfacial properties; (4) molecular modelling, computer simulation; (5) reactions, spectroscopy; (6) phase separation kinetics; (7) extractions; (8) applications to polymers, pharmaceuticals, natural materials and chromatography; (9) process scale-up.




Supercritical Fluid Cleaning


Book Description

Although supercritial fluid (SCF) technology is now widely used in extraction and purification processes (in the petrochemical, food and pharmaceuticals industries), this book is the first to address the new application of cleaning. The objective is to provide a roadmap for readers who want to know whether SCF technology can meet their own processing and cleaning needs. It is particularly helpful to those striving to balance the requirements for a clean product and a clean environment. The interdisciplinary subject matter will appeal to scientists and engineers in all specialties ranging from materials and polymer sciences to chemistry and physics. It is also useful to those developing new processes for other applications, and references given at the end of each chapter provide links to the wider body of SCF literature. The book is organized with topics progressing from the fundamental nature of the supercritical state, through process conditions and materials interactions, to economic considerations. Practical examples are included to show how the technology has been successfully applied. The first four chapters consider principles governing SCF processing, detailing issues such as solubility, design for cleanability, and the dynamics of particle removal. The next three chapters discuss surfactants and microemulsions, SCF interaction with polymers, and the use of supercritical carbon dioxide (CO2) as a cleaning solvent. The closing chapters focus on more practical considerations such as scaleup, equipment costs, and financial analysis.




Applications of Supercritical Fluids in Industrial Analysis


Book Description

The continued search for rapid, efficient and cost-effective means of analytical measurement has introduced supercritical fluids into the field of analytical chemistry. Two areas are common: supercritical fluid chroma tography and supercritical fluid extraction. Both seek to exploit the unique properties of a gas at temperatures and pressures above the critical point. The most common supercritical fluid is carbon dioxide, employed because of its low critical temperature (31 °C), inertness, purity, non-toxicity and cheapness. Alternative supercritical fluids are also used and often in conjunction with modifiers. The combined gas-like mass transfer and liquid-like solvating characteristics have been used for improved chroma tographic separation and faster sample preparation. Supercritical fluid chromatography (SFC) is complementary to gas chro matography ( GC) and high performance liquid chromatography (HPLC), providing higher efficiency than HPLC, together with the ability to analyse thermally labile and high molecular weight analytes. Both packed and open tubular columns can be employed, providing the capability to analyse a wide range of sample types. In addition, flame ionization detection can be used, thus providing 'universal' detection.




Advances in Polymer Processing


Book Description

Processing techniques are critical to the performance of polymer products which are used in a wide range of industries. Advances in polymer processing: From macro- to nano- scales reviews the latest advances in polymer processing, techniques and materials.Part one reviews the fundamentals of polymer processing with chapters on rheology, materials and polymer extrusion. Part two then discusses advances in moulding technology with chapters on such topics as compression, rotational and blow moulding of polymers. Chapters in Part three review alternative processing technologies such as calendaring and coating, foam processing and radiation processing of polymers. Part four discusses micro and nano-technologies with coverage of themes such as processing of macro, micro and nanocomposites and processing of carbon nanotubes. The final section of the book addresses post-processing technologies with chapters on online monitoring and computer modelling as well as joining, machining, finishing and decorating of polymers.With is distinguished editors and team of international contributors, Advances in polymer processing: From macro- to nano- scales is an invaluable reference for engineers and academics concerned with polymer processing. - Reviews the latest advances in polymer processing, techniques and materials analysing new challenges and opportunities - Discusses the fundamentals of polymer processing considering the compounding and mixing of polymers as well as extrusion - Assesses alternative processing technologies including calendaring and coating and thermoforming of polymers




Product, Process and Plant Design Using Subcritical and Supercritical Fluids for Industrial Application


Book Description

This book describes cutting edge technology using supercritical fluids for the production of foodstuffs, medicals, and polymers. It illustrates the importance and use of basic data for design and operation at industrial scale units. The book's authors have several decades of experience of applied research on how to develop large scale industrial units. It provides readers complete insight in design and operation of industrial high pressure process plants. The book is written so it may be understood for people (with?) little or no background on high pressure process technology. It will provide information on how some foodstuffs, medicals, polymers are produced using high pressure technologies. The book demonstrates the importance of fundamental data, how to measure them and how to apply them to design industrial plants. At the same time, it also serves as a textbook for students.




Handbook on Supercritical Fluids


Book Description

Supercritical fluid carbon dioxide (sc-CO2) possesses both gas-like and liquid-like properties. It is capable of depositing nanoparticles in small structures and poorly wettable substrates. Deposition and array formation of metal and metal sulphide nanoparticles on various substrates using sc-CO2 as a medium has been a subject of considerable interest for researchers in nanomaterials area in recent years. This handbook begins by exploring nanoparticle deposition using supercritical fluid carbon dioxide. Further topics in this handbook include separation of oils using supercritical carbon dioxide; the application of an integrated supercritical extraction and impregnation process for incorporation of thyme extracts into different carriers; supercritical fluid extraction application on dairy products and by-products; and supercritical fluid technology applications in pharmaceutical drug formulations.




Analytical Supercritical Fluid Extraction


Book Description

Recent advances in analytical chemistry have turned it into a virtually unrecognizable science compared to a few decades ago, when it lagged behind other sciences and techniques. However, advances in analytical science have been far from universal: while innovations in instrumentation and data acquisition and processing systems have reached unprecedented levels thanks to parallel breakthroughs in computer science and chemo metrics, progress in preliminary operations has been much slower despite their importance to analytical results. Thus, such clear trends in analytical process development as automation and miniaturization have not reached preliminary operations to the same extent, even though this area is pro bably in the greatest need. Improvement in preliminary operations is thus an urgent goal of analytical chemistry on the verge of the twenty first century. Increased R&D endeavours and manufacture of commercially available automatic equipment for implementation of the wide variety of operations that separate the uncollected, unmeasured, untreated sample from the signal measuring step are thus crucial on account of the wide variability of such operations, which precludes development of all-purpose equipment, and the complexity of some, particularly relating to solid samples. Supercritical fluid extraction opens up interesting prospects in this context and is no doubt an effective approach to automatioI1 and mini aturization in the preliminary steps of the analytical process. The dramatic developments achieved in its short life are atypical in many respects.




Supercritical Fluids


Book Description

Supercritical fluids which are neither gas nor liquid, but can be compressed gradually from low to high density, are gaining increasing importance as tunable solvents and reaction media in the chemical process industry. By adjusting the pressure, or more strictly the density, the properties of these fluids are customized and manipulated for the particular process at hand, be it a physical transformation, such as separation or solvation, or a chemical transformation, such as a reaction or reactive extraction. Supercritical fluids, however, differ from both gases and liquids in many respects. In order to properly understand and describe their properties, it is necessary to know the implications of their nearness to criticality, to be aware of the complex types of phase separation (including solid phases) that occur when the components of the fluid mixture are very different from each other, and to develop theories that can cope with the large differences in molecular size and shape of the supercritical solvent and the solutes that are present.