Download or read book From linear to long chain branched poly ethylene terephthalate reactive extrusion rheology and molecular characterization written by Kruse, Matthias and published by Universitätsverlag der TU Berlin. This book was released on 2017-07-11 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: Poly(ethylene terephthalate) is one of the most widely used polymers in packaging industry, due to its high mechanical strength, chemical resistance, and barrier functions. However, its processing is determined by degradation and low viscosity. In particular, foaming and film blowing is restricted by the linear structure of the molecule and low melt strength. The stability of three linear commercial PET grades produced by different synthesis routes with different molar masses is analyzed in regards of processing at industrial scale. Subsequently, reactive processing with three multi-functional chain extenders (pyromellitic dianhydride, PMDA, tetraglycidyl diamino diphenyl methane, TGDDM, and triphenyl phosphite, TPP) is conducted to create large and long-chain branched (LCB) molecules. The mechanical and molecular properties in melt state are analyzed by linear and non-linear viscoelastic rheology, modeling by the molecular stress function (MSF) theory and size-exclusion chromatography (SEC) with light scattering measurements. Thermal stability measurements in the linear viscoelastic regime revealed degradation and a reduction of the storage modulus in air atmosphere, and, besides thermal degradation, an enhancement of the modulus in nitrogen atmosphere, due to polycondensation [Kruse et al., 2013]. Fitting by an exponential function leads to the reconstruction of the initial state of the sample at zero-loading time and to a time constant, which reveals clear relations between stability and molar mass for all three PET grades in both atmospheres. High molar mass PET is more stable in nitrogen and less stable in air environment, and vice versa, depending on OH end group concentration and synthesis route. The analysis by means of time-resolved mechanical spectroscopy allows the observations of moduli and complex viscosity at a fixed time, a wide range of angular frequencies, and at different atmospheres, and revealed: (i) a plasticizer effect induced by small molecules from thermal and thermo-oxidative degradation, (ii) cross-linking leading to yield stress, (iii) diffusion influencing polycondensation reaction, (iv) slipping due to deposition of side products, and (v) an enhanced shear thinning regime [Kruse and Wagner, 2016]. The extrusion of neat PET with a twin-screw extruder at industrial scale leads to strong reduction of viscosity mainly due to shearing. The impact of thermo-oxidative degradation is comparably small. The reactive processing of the three PET grades with the three chain extenders leads to the conclusion that the tri-functional TPP is not a useful chain extender due to rapid degradation and toxicity. The two tetra-functional chain extenders, PMDA and the epoxy-based TGDDM, lead to strong viscosity increase, increasing strain hardening effect, and increasing thermal stability with increasing chain extender concentration as confirmed by loss- and storage modulus, phase angle, activation energy of flow, and elongational viscosity. The MSF model predictions show good agreement with data measured, and allowed a quantitative analysis of the branching structure and of the stretch of the molecules by both non-linear MSF parameters. In comparison to the high molar mass PET with an apparent comb-like structure at high PMDA concentrations, the two initially low molar mass grades show a higher molar mass after processing with PMDA and seem to have a tree-like structure, which can be explained by the hydroxyl end group concentration of these two PET grades. The extensive use of TGDDM leads to a hyperbranched and gel-like structure. The fracture analysis from uniaxial elongation experiments reveals a limiting stress value for high PMDA concentrations and a limiting strain value for high TGDDM concentrations due to formation of a covalent network. The molecular analysis by SEC with triple detection of the high molar mass PET, which was reacted with PMDA and TGDDM, shows a strong increase of the average molar masses, polydispersity, radius of gyration, and hydrodynamic radius and confirms the molar mass increase observed by the rheological measurements. The branching was confirmed by a decreasing Mark-Houwink exponent with increasing chain extender concentration. Further, the analysis of the contraction of the molecule revealed a more star-like structure at low concentrations for both chain extenders. With increasing concentration, the structure changed to more comb-like for PMDA and random tree-like or hyperbranched for TGDDM as was also observed by non-linear viscoelastic measurements. PMDA revealed to be an excellent coupling agent which induces reproducibly either a star-like, comb-like, or tree-like structures depending on the concentration of coupling agent added and the hydroxyl concentration of the PET employed. Polyethylenterephthalat (PET) zeichnet sich durch hervorragende mechanische Eigenschaften, sowie chemische Beständigkeit und Barriereeigenschaften aus und findet insbesondere in der Verpackungsindustrie Verwendung. Die Neigung zur Degradation und die wegen der linearen Kettenmoleküle geringe Viskosität schränken jedoch die Verarbeitbarkeit von PET wie beispielsweise das Schäumen und Folienblasen erheblich ein. In der vorliegenden Arbeit wird der Einfluss der thermischen Stabilität während der Verarbeitung von drei linearen industriellen PET-Typen untersucht, die sich durch Molmasse und Herstellungsverfahren unterscheiden. Des Weiteren wird langkettenverzweigtes PET (LCBPET) durch reaktive Verarbeitung mit drei verschiedenen multifunktionalen Kettenverlängerern, Pyromellitsäuredianhydrid (PMDA), Tetra- glycidyl-Diamino-Diphenyl-Methan (TGDDM) und Triphenylphosphit (TPP), hergestellt und charakterisiert. Durch die experimentelle Bestimmung der linearen und nichtlinearen rheologischen Eigenschaften der Schmelze und ihre Beschreibung mit Hilfe des sogenannten "Molecular Stress Function" (MSF) Modells gelingt eine quantitative Analyse des Materialverhaltens. Die molekulare Analyse wird zusätzlich durch die Ergebnisse von Gelpermeationschromatographie (GPC bzw. SEC) in Verbindung mit Lichtstreumessung gestützt. Die Untersuchungen der thermischen Stabilität von linearem PET im linear-viskoelastischen Bereich zeigen einen abnehmenden Speichermodul und somit ein thermo-oxidatives Degradationsverhalten in Luftatmosphäre. In inerter Stickstoffatmosphäre tritt hingegen nur thermische Degradation auf, gleichzeitig führt jedoch eine Polykondensationsreaktion zu einem Anstiegen des Moduls [Kruse et al., 2013]. Mit einem exponentiellen Regressionsansatz kann der anfängliche Zustand des Moduls in beiden Atmosphären zum Zeitpunkt Null, der dem Einbringen der Probe in das Rheometer entspricht, rekonstruiert werden. Die sich aus diesem Ansatz ergebende Zeitkonstante erlaubt es, quantitative Zusammenhänge zwischen der thermischen Stabilität der drei PET-Sorten und deren Molmasse sowie dem Herstellungsverfahren der PET-Typen aufzuzeigen. So weist hochmolekulares PET eine höhere Stabilität in Stickstoff und eine geringere Stabilität in Luft auf und umgekehrt. Hauptursache für dieses Verhalten ist die unterschiedliche Konzentration an Hydroxylendgruppen, die je nach Molmasse und Herstellungsmethode der jeweiligen PET-Typen variiert. Mit Hilfe der "Time-Resolved Mechnical Sprectroscopy" konnte die sich ändernde Viskosität über ein weites Frequenzspektrum und zu einer beliebigen Messzeit in beiden Atmosphären bestimmt werden. Wesentliche Ergebnisse dieser Untersuchung sind der Nachweis des Auftretens von (i) einem Weichmachereffekt bedingt durch die thermische und thermo-oxidative Degradation und den daraus resultierenden Oligomeren, (ii) dreidimensionaler Vernetzung mit der Ausbildung einer Fließgrenze, (iii) Diffusionsprozessen, die Einfluss auf die Polykondensationsreaktion haben, (iv) Wandgleiten, bedingt durch die Ablagerung von Nebenprodukten auf den Platten des Rheometers und (v) einem verbreiterten Scherverdünnungbereich [Kruse and Wagner, 2016]. Die Extrusion von linearem PET mit einem Doppelschneckenextruder unter industriellen Bedingungen führt zu einer starken Abnahme der Viskosität, die hauptsächlich durch Scherung und weniger durch thermo-oxidativen Abbau verursacht wird. Bei der reaktiven Verarbeitung der drei PET-Typen mit den drei verschiedenen Kettenverlängerern erwies sich das dreifunktionale TPP auf Grund von Toxizität und Lagerinstabilitäten als unbrauchbar. Die Verarbeitung der beiden vierfunktionalen Kettenverlängerer, PMDA und das epoxidhaltige TGDDM, führt zu erhöhter Viskosität, erhöhter Dehnverfestigung und erhöhter thermischer Stabilität mit zunehmender Konzentration des jeweiligen Kettenverlängerers. Das beschriebene Verhalten zeigt sich sowohl am Speicher- und Verlustmodul und dem daraus abgeleiteten Verlustwinkel, als auch an der Fließaktivierungsenergie und der Dehnviskosität. Dabei lassen sich die gemessenen Dehnviskositäten sehr präzise mit dem MSF-Modell beschreiben und die beiden nichtlinearen Modelparameter, β und f_max^2 ermöglichen eine quantitative Analyse der Verzweigungsstruktur und der Molekülstreckung. So zeigt die Modifiziereng von hohen PMDA-Konzentrationen und dem hochmolekularen PET eine mehr kammartige Struktur im Vergleich zu den beiden niedermolekularen PET-Typen, die eine baumartige Molekülstruktur und eine höhere Molmasse nach der reaktiven Extrusion aufweisen. Beide Effekte können mit der höheren OH-Endgruppenkonzentration der beiden niedermolekularen PET-Typen erklärt werden. Zu hohe Zusätze von TGDDM führen zu einem hochverzweigten und gelartigen Polymer. Das Bruchverhalten bei der uniaxialen Dehnung von mit einem hohen Zusatz von PMDA hergestellten langkettenverzweigten PET wird von einer limitierenden Bruchspannung bestimmt. Demgegenüber bestimmt eine maximale Dehnung das Bruchverhalten des mit einem hohen TGDDM-Zusatz hergestellten LCB-PET, verursacht durch ein kovalent gebundenes Polymernetzwerk. Die GPC Messungen mit drei Detektoren wurden an LCB-PET durchgeführt, das auf Basis der hochmolekularen PET-Type hergestellt wurde. Die molekulare Analyse der mit PMDA und TGDDM modifizierten Proben zeigt eine deutliche Zunahme der mittleren Molmassen, Molmassenverteilungsbreite, des Gyrationsradius und des hydrodynamischen Radius und bestätigt somit die rheologischen Ergebnisse. Das Auftreten von Verzweigungen wird außerdem durch den abnehmenden Mark-Houwink-Exponenten bei zunehmender Additivkonzentration verdeutlicht. Eine genauere Betrachtung weist auf eine sternartige Molekülstruktur bei geringer Zugabe beider Kettenverlängerer hin. Bei erhöhter Zugabe hingegen tritt eine kammartige Struktur bei PMDA und eine baumartige oder hochverzweigte Struktur bei TGDDM auf, wie auch aus den nichtlinearen viskoelastischen Messungen zu schließen ist. Insbesondere PMDA erweist sich als hervorragender Kettenverlängerer, der bei reaktiver Extrusion reproduzierbar eine sternartige, kammartige oder baumartige Molekülstruktur in Abhängigkeit von der verwendeten PET-Type und der PMDA-Konzentration ermöglicht und so das Verarbeitungsspektrum von PET auf neue Anwendungsgebiete erweitert.
Download or read book From Linear to Long chain Branched Poly ethylene Terephthalate Reactive Extrusion Rheology and Molecular Characterization written by Matthias Kruse and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Macromolecular Chemistry and Physics written by and published by . This book was released on 2006 with total page 680 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ei Engineering Conference Index pt 1 Civil environmental and geological engineering written by and published by . This book was released on 1985 with total page 1412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Maro Polymer Notes written by and published by . This book was released on 2000 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solid State Polymerization written by Constantine D. Papaspyrides and published by John Wiley & Sons. This book was released on 2009-04-27 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most current guide to solid state polymerization Solid State Polymerization (SSP)is an indispensable tool in the design, manufacture, and study of polymers, plastics, and fibers. SSP presents significant advantages over other polymerization techniques due to low operating temperatures, inexpensive equipment, and simple and environmentally sound procedures. Combining fundamentals of polymer science, chemistry, physical chemistry, and engineering, SSP also offers many research applications for a wide range of students and investigators. Gathering and filtering the latest literature on SSP, Solid Solid State Polymerization offers a unique, one-stop resource on this important process. With chapters contributed by leaders in the field, this text summarizes SSP, and provides essential coverage that includes: An introduction to SSP, with chemical and physical steps, apparatus, advantages, and parameters SSP physical chemistry and mechanisms Kinetic aspects of polyesters and polyamides SSP Catalysis in SSP processes Application of SSP under high pressure conditions in the laboratory Engineering aspects regarding process modeling and industrial application Recent developments and future possibilities Solid State Polymerization provides the most up-to-date coverage of this constantly developing field to academic and industry professionals, as well as graduate and postgraduate-level students in chemical engineering, materials science and engineering, polymer chemistry, polymer processing and polymer engineering.
Download or read book Elastic Behavior of Polymer Melts written by Helmut Münstedt and published by Carl Hanser Verlag GmbH Co KG. This book was released on 2019-07-08 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the elastic properties of polymer melts is necessary for ensuring successful polymer processing and thus producing high-quality plastic parts. This unique book is the first to focus on this important topic. Starting with the molecular origin of elastic behavior and an explanation of the physical quantities involved, experimental methods and the dependence of elastic behavior on experimental parameters are then presented. Elastic properties of filled and unfilled systems are compared directly, and polymer blends are also considered. Elastic effects in various applications are included, such as in extrudate swell, internal stresses, and shrink films, to illustrate the importance of this field in the plastics processing industry.
Download or read book Polymer Science and Engineering written by National Research Council and published by National Academies Press. This book was released on 1994-01-01 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers are used in everything from nylon stockings to commercial aircraft to artificial heart valves, and they have a key role in addressing international competitiveness and other national issues. Polymer Science and Engineering explores the universe of polymers, describing their properties and wide-ranging potential, and presents the state of the science, with a hard look at downward trends in research support. Leading experts offer findings, recommendations, and research directions. Lively vignettes provide snapshots of polymers in everyday applications. The volume includes an overview of the use 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 polymersâ€"plastics, fibers, composites, and other materials, as well as polymers used as membranes and coatingsâ€"and how their composition and specific methods of processing result in unparalleled usefulness. The reader can also learn the science behind the technology, including efforts to model polymer synthesis after nature's methods, and breakthroughs in characterizing polymer properties needed for twenty-first-century applications. This informative volume will be important to chemists, engineers, materials scientists, researchers, industrialists, and policymakers interested in the role of polymers, as well as to science and engineering educators and students.
Download or read book Reactive Extrusion written by Günter Beyer and published by John Wiley & Sons. This book was released on 2018-01-03 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first comprehensive overview of reactive extrusion technology for over a decade combines the views of contributors from both academia and industry who share their experiences and highlight possible applications and markets. They also provide updated information on the underlying chemical and physical concepts, summarizing recent developments in terms of the material and machinery used. As a result, readers will find here a compilation of potential applications for reactive extrusion to access new and cost-effective polymeric materials, while using existing compounding machines.
Download or read book Polymer Carbon Nanotube Composites written by Tony McNally and published by Elsevier. This book was released on 2011-03-28 with total page 849 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the properties of polymer carbon nanotube (CNT) composites is the key to these materials finding new applications in a wide range of industries, including but not limited to electronics, aerospace and biomedical/bioengineering. Polymer-carbon nanotube composites provides comprehensive and in-depth coverage of the preparation, characterisation, properties and applications of these technologically interesting new materials. Part one covers the preparation and processing of composites of thermoplastics with CNTs, with chapters covering in-situ polymerization, melt processing and CNT surface treatment, as well as elastomer and thermoset CNT composites. Part two concentrates on properties and characterization, including chapters on the quantification of CNT dispersion using microscopy techniques, and on topics as diverse as thermal degradation of polymer/CNT composites, the use of rheology, Raman spectroscopy and multi-scale modelling to study polymer/CNT composites, and CNT toxicity. In part three, the applications of polymer/CNT composites are reviewed, with chapters on specific applications such as in fibres and cables, bioengineering applications and conductive polymer CNT composites for sensing. With its distinguished editors and international team of contributors, Polymer-carbon nanotube composites is an essential reference for scientists, engineers and designers in high-tech industry and academia with an interest in polymer nanotechnology and nanocomposites. Provides comprehensive and in-depth coverage of the preparation, characterisation and properties of these technologically interesting new materials Reviews the preparation and processing of composites of thermoplastics with CNTs, covering in-situ polymerization, melt processing and CNT surface treatment Explores applications of polymer/CNT composites such as in fibres and cables, bioengineering applications and conductive polymer CNT composites for sensing
Download or read book Plastics in Medical Devices for Cardiovascular Applications written by Ajay Padsalgikar and published by William Andrew. This book was released on 2017-02-01 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plastics in Medical Devices for Cardiovascular Applications enables designers of new cardiovascular medical devices to make decisions about the kind of plastics that can go into the manufacture of their device by explaining the property requirements of various applications in this area, including artificial valves, lead insulation, balloons, vascular grafts, and more. Enables designers to improve device performance and remain compliant with regulations by selecting the best material for each application Presents a range of applications, including artificial valves, stents, and vascular grafts Explains which materials can be used for each application, and why each is appropriate, thus assisting in the design of better tools and processes
Download or read book Modern Polyesters written by John Scheirs and published by John Wiley & Sons. This book was released on 2005-09-01 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides an overview of the family of polyester polymers which comprise an important group of plastics that span the range of commodity polymers to engineering resins. It describes the preparation, properties and applications of polyesters. Readers will also find details on polyester-based elastomers, biodegradable aliphatic polyester, liquid crystal polyesters and unsaturated polyesters for glass-reinforced composites. Presents an overview of the most recent developments. Explores synthesis, catalysts, processes, properties and applications. Looks at emerging polyester materials as well as existing ones. Written by foremost experts from both academia and industry, ensuring that both fundamentals and practical applications are covered.
Download or read book Extrusion written by Harold F. Giles Jr and published by William Andrew. This book was released on 2013-09-21 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of Extrusion is designed to aid operators, engineers, and managers in extrusion processing in quickly answering practical day-to-day questions. The first part of the book provides the fundamental principles, for operators and engineers, of polymeric materials extrusion processing in single and twin screw extruders. The next section covers advanced topics including troubleshooting, auxiliary equipment, and coextrusion for operators, engineers, and managers. The final part provides applications case studies in key areas for engineers such as compounding, blown film, extrusion blow molding, coating, foam, and reprocessing. This practical guide to extrusion brings together both equipment and materials processing aspects. It covers basic and advanced topics, for reference and training, in thermoplastics processing in the extruder. Detailed reference data are provided on such important operating conditions as temperatures, start-up procedures, shear rates, pressure drops, and safety. A practical guide to the selection, design and optimization of extrusion processes and equipment Designed to improve production efficiency and product quality Focuses on practical fault analysis and troubleshooting techniques
Download or read book Light Scattering Size Exclusion Chromatography and Asymmetric Flow Field Flow Fractionation written by Stepan Podzimek and published by John Wiley & Sons. This book was released on 2011-04-20 with total page 325 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive, practical approach to three powerful methods of polymer analysis and characterization This book serves as a complete compendium of three important methods widely used for the characterization of synthetic and natural polymers—light scattering, size exclusion chromatography (SEC), and asymmetric flow field flow fractionation (A4F). Featuring numerous up-to-date examples of experimental results obtained by light scattering, SEC, and A4F measurements, Light Scattering, Size Exclusion Chromatography and Asymmetric Flow Field Flow Fractionation takes an all-in-one approach to deliver a complete and thorough explanation of the principles, theories, and instrumentation needed to characterize polymers from the viewpoint of their molar mass distribution, size, branching, and aggregation. This comprehensive resource: Is the only book gathering light scattering, size exclusion chromatography, and asymmetric flow field flow fractionation into a single text Systematically compares results of size exclusion chromatography with results of asymmetric flow field flow fractionation, and how these two methods complement each other Provides in-depth guidelines for reproducible and correct determination of molar mass and molecular size of polymers using SEC or A4F coupled with a multi-angle light scattering detector Offers a detailed overview of the methodology, detection, and characterization of polymer branching Light Scattering, Size Exclusion Chromatography and Asymmetric Flow Field Flow Fractionation should be of great interest to all those engaged in the polymer analysis and characterization in industrial and university research, as well as in manufacturing quality control laboratories. Both beginners and experienced can confidently rely on this volume to confirm their own understanding or to help interpret their results.
Download or read book Structure and Rheology of Molten Polymers written by John M. Dealy and published by Carl Hanser Verlag GmbH Co KG. This book was released on 2018-02-12 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in polymer science have made it possible to relate quantitatively molecular structure to rheological behavior. At the same time, new methods of synthesis and characterization allow the preparation and structural verification of samples having a range of branched polymeric structures. This book unites this knowledge to enable production of polymers with prescribed processability and end-product properties. Methods of polymer synthesis and characterization are described, starting from fundamentals. The foundations of linear viscoelasticity are introduced, and then the linear behavior of entangled polymers is described in detail. This is followed by a discussion of the molecular modeling of linear behavior. Tube models for both linear and branched polymers are presented. The final two chapters deal with nonlinear rheological behavior and tube models to describe nonlinearity. In this second edition, each chapter has been significantly rewritten to account for recent advances in experimental methods and theoretical modeling. It includes new and updated material on developments in polymer synthesis and characterization, computational algorithms for linear and nonlinear rheology prediction, measurement of nonlinear viscoelasticity, entanglement detection algorithms in molecular dynamics, nonlinear constitutive equations, and instabilities. Contents: - Structure of Polymers - Polymerization Reactions and Processes - Linear Viscoelasticity - Fundamentals - Linear Viscoelasticity - Behavior of Molten Polymers - Tube Models for Linear Polymers - Fundamentals - Tube Models for Linear Polymers - Advanced Topics - Determination of Molecular Weight Distribution Using Rheology - Tube Models for Branched Polymers - Nonlinear Viscoelasticity - Tube Models for Nonlinear Viscoelasticity of Linear and Branched Polymers
Download or read book Melt Rheology and Its Role in Plastics Processing written by K. Wissbrun and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is designed to fulfill a dual role. On the one hand it provides a description of the rheological behavior of molten poly mers. On the other, it presents the role of rheology in melt processing operations. The account of rheology emphasises the underlying principles and presents results, but not detailed deriva tions of equations. The processing operations are described qualita tively, and wherever possible the role of rheology is discussed quantitatively. Little emphasis is given to non-rheological aspects of processes, for example, the design of machinery. The audience for which the book is intended is also dual in It includes scientists and engineers whose work in the nature. plastics industry requires some knowledge of aspects of rheology. Examples are the polymer synthetic chemist who is concerned with how a change in molecular weight will affect the melt viscosity and the extrusion engineer who needs to know the effects of a change in molecular weight distribution that might result from thermal degra dation. The audience also includes post-graduate students in polymer science and engineering who wish to acquire a more extensive background in rheology and perhaps become specialists in this area. Especially for the latter audience, references are given to more detailed accounts of specialized topics, such as constitutive relations and process simulations. Thus, the book could serve as a textbook for a graduate level course in polymer rheology, and it has been used for this purpose.
Download or read book Polymer Characterisation written by B.J. Hunt and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers continue to play an ever increasing role in the modern world. In fact it is quite inconceivable to most people that we could ever have existed of the increased volume and variety of materials without them. As a result currently available, and the diversity of their application, characterisation has become an essential requirement of industrial and academic laboratories in volved with polymeric materials. On the one hand requirements may come from polymer specialists involved in the design and synthesis of new materials who require a detailed understanding of the relationship between the precise molecular architecture and the properties of the polymer in order to improve its capabilities and range of applications. On the other hand, many analysts who are not polymer specialists are faced with the problems of analysing and testing a wide range of polymeric materials for quality control or material specification purposes. We hope this book will be a useful reference for all scientists and techno or industrial laboratories, logists involved with polymers, whether in academic and irrespective of their scientific discipline. We have attempted to include in one volume all of the most important techniques. Obviously it is not possible to do this in any great depth but we have encouraged the use of specific examples to illustrate the range of possibilities. In addition numerous references are given to more detailed texts on specific subjects, to direct the reader where appropriate. The book is divided into II chapters.
