Download or read book Copolymerization of Dienes from Mechanistic Insights Towards Material Properties of Multiblock Copolymers written by Ramona Denise Barent and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the groundbreaking work of Hermann Staudinger in 1920, polymer science has evolved tremendously for more than 100 years into manifold directions, impacting countless parts of life. Naming only a few disciplines, polymers find an omnipresent application in the automotive and the construction sector. Their insulating or semiconducting properties are pivotal for electric and electronic devices, whereas membrane technologies rely on their separation capability, and both the medical and the agricultural sector benefit from advanced polymer structures for controlled drug release. Yet, macromolecules played a crucial role long before they were recognized, studied in depth and specialized for targeted applications. For instance, natural rubber has been commercialized for almost the past two centuries, with Charles Goodyear's and Thomas Hancock's vulcanization process providing the basis for stable elastomeric materials. The introduction of synthetic thermoplastic elastomers (TPEs) in the 20th century, possessing the processability of thermoplastics and the elasticity of vulcanized rubber, and progress in understanding the chemical nature and the resulting material properties allows for envisioning versatile characteristics. With the living anionic polymerization technique at hand, which is the method of choice for the synthesis of complex but well-defined polymer architectures, new challenges designing materials with tailored physical properties can be met. The first part of this thesis aspires to elucidate the influence of an (IS)nI multiblock architecture on the materials' properties in bulk, whereas the second part evaluates their solution characteristics. At the end of this work a fundamental framework for the living anionic polymerizability in non-polar media is outlined. Chapter 1 gives a general introduction to the versatile toolbox of living anionic polymerization against the background of their use as thermoplastic elastomers (TPEs). After a brief outline of the historical background of elastomers and current application fields of TPEs, this review focuses on synthetic approaches tailoring the polymers' and in turn the materials ́ properties. In particular, inherent mechanical properties are discussed with respect to the phase segregation strength and the resulting microdomain morphologies. The highlighted synthetic strategies focus on lithium initiated living anionic (co)polymerizations of different styrenic and 1,3-diene monomers in hydrocarbons, further emphasizing the influence of modifiers on the block profile in statistical copolymers. In this regard, not only the block profile, but also the influence of the block sequence, the block number, and the polymer chain architecture are elaborated. Furthermore, the benefit of in situ monitoring techniques to determine kinetic parameters is demonstrated and expanded on kinetic Monte Carlo simulations, which allow for the calculation of reaction times, greatly facilitating the workflow of multiblock syntheses. Chapter 2 reviews the use of plasticized poly(vinyl chloride) for medical devices. In the first part health concerns related to the commonly used plasticizer are discussed within the framework of human exposure and its metabolism. The second and third part evaluate potential solutions by the introduction of different plasticizers and by the replacement of PVC by alternative polymer materials, respectively. For the latter, a project funded by the European Commission addressing the implementation of polyolefins for medical bags and the use of styrenic thermoplastic elastomers for healthcare applications are considered in greater detail. Chapter 3 highlights the structural and mechanical investigation of polyisoprene-polystyrene multiblock copolymers with two polyisoprene end blocks. These structures are of interest due to the potential internal plasticizer effect of the flexible end blocks, probably rendering a soft but resilient material. Temperature-dependent small-angle x-ray scattering experiments were implemented to investigate the phase separated morphologies of both sequential and tapered (IS)nI multiblock copolymers covering a wide range of molar masses and block numbers. A strong decrease in the segregation strength and hence of the order-disorder temperature was proven, comparing sequential block copolymers with a defined transition between the adjacent blocks with tapered block-like copolymers with a sharp, but gradual comonomer transition in each polyisoprene-polystyrene diblock sequence. This is caused by the reduced enthalpic incompatibility in tapered structures. While the sequential multiblock copolymers exhibited well-ordered lamellar morphologies, the tapered counterparts showed weakly- ordered perforated layers. The viscoelastic responses measured by tensile tests evidenced superior resilience for the sequential structures, while the tapered structures revealed a higher softness and flexibility. The concomitant decrease of the block size by increasing the block number at a given overall molar mass is accompanied by an increased domain bridging, but at the same time a weakened microphase separation. Due to this trade-off, the higher molar mass tapered pentablocks and sequential heptablocks were found to best balance these opposite effects, resulting in a significant mechanical toughness. Interestingly, polymers with the same molar mass per block exhibited comparable domain spacings and hence softness, while the ultimate deformability was found to increase with the extension by a diblock sequence due to an enhanced domain bridging. Comparison with a literature-known analogous structure with two polystyrene end blocks revealed an easier deformability of the structure with two polyisoprene end blocks reasoned in a smaller domain size. Chapter 4 further elaborates the mechanical properties of polyisoprene-polystyrene multiblock copolymers with different architectures in terms of chain connectivity. This fundamental research is intriguing due to the potential to minimize the issue of permanent sets upon large deformation while preserving the advantage of easily processable and reprocessable materials. Uniaxial tensile tests as well as recovery measurements were performed comparing linear tapered SIS triblock copolymers with linear (SIS)2 pentablock and star-shaped (SIS)4 multiblock copolymers featuring vitrifying core and end blocks. The advanced architectures were synthesized by an “arm-first” approach coupling the (SIS) arms. For small molar masses per arm, the star-shaped multiblock architectures showed superior ultimate stress and strain at break reflected in a higher toughness, which can be ascribed to their higher bridging fraction. For higher molar masses, the ultimate mechanical properties of the linear pentablock copolymers and the star-shaped structures approached each other reaching a plateau value, showing that at this point the covalent linkage of the star architecture does not provide further resilience. Yet, they still outperformed the simple triblock structure, further emphasizing the importance of large fractions of bridged chain conformations. For polymers with the same overall molar mass, the star-shaped multiblock copolymers could not compete with the linear pentablock copolymers due to an inferior phase segregation and hence facilitated chain pull-out. For three counterparts of equal molar mass per arm, which showed decent phase segregation and comparable ultimate properties, the cyclic strain experiments evidenced striking differences in their recovery behavior. While the star-shaped (SIS)4 multiblock copolymer showed unprecedented final recovery after 5 minutes of rest, they exhibited poor initial recovery during receding. In contrast, the linear structures feature superior rapid recovery but smaller final recoveries after resting. These phenomena prove the higher chain flexibility of the linear architectures being responsible for fast restoring, while the even stress distribution in star-shaped architectures with a covalent core junction generates improved shape memory. However, at high stress levels all specimens experienced a permanent set due to substantial restructuring, resulting in converging restoring properties. Chapter 5 examines the three most decisive tribological parameters dictating the performance of viscosity modifiers in lubricating oils relating to not only commonly implemented, but also novel polymer classes. Moving metal parts have to be lubricated in order to prevent friction. However, lubricating fluids face a rapid viscosity decrease upon increasing temperature. Therefore, viscosity modifiers are added to attenuate the adverse effects of asperity contact. Yet, optimum performance in all of the three key metrics, i.e., a beneficial viscosity-temperature relationship, thickening efficiency, and shear stability has not been achieved so far. Since these tribological parameters are complexly intercorrelated, their balancing is challenging, which is the reason for the demand for novel lubricant additives. The influence of key polymer characteristics such as molar mass, dispersity, chain composition, and architecture on the hydrodynamic volume and by this on the tribological parameters are accentuated. Furthermore, the chemical nature of the commonly implemented polymer classes comprising poly(alkyl methacrylates), olefinic copolymers, and hydrogenated styrene- diene copolymers is reviewed with respect to their polymerization mechanism and the inherent thickening mechanisms for viscosity improvement. The latter include the coil expansion mechanism prominent in poly(alkyl methacrylate) formulations and association phenomena featured by hydrogenated styrene-diene copolymers. Beyond this, advanced structures aiming at exceeding the current performance limits are discussed. Here, blending approaches and new polymer classes like poly(2-oxazolines) and poly(2-oxazines), but also sophisticated architectures like brush-like, comb-like or linear (tapered) multiblock copolymer structures are emphasized. This promising combination of several benefits gives food for further investigations. Chapter 6 addresses the self-organization of multiblock copolymers with both a defined and a gradual block profile in the polyisoprene-selective solvent heptane. Conclusions on the aggregate structures are drawn based on the diffusion behavior at varying concentrations. For this purpose, dilute and concentrated polymer solutions are examined by dynamic light scattering using a cross-correlation approach, which allows to study diffusion processes even in the presence of multiple scattering events. Diverging diffusion coefficients for the triblock and multiblock copolymers at a polymer concentration above 1 wt% proved the formation of non-ergodic systems, i.e., polymer networks, in case of the structures with several solvophobic polystyrene blocks. Complementary fluorescence correlation spectroscopy measurements permitted insights into the self-diffusion of unimers through these polymer networks. These processes were found to be most restricted in networks of sequential multiblock copolymers, which is the consequence of a denser network due to a higher bridging fraction in combination with larger unimer dimensions. The unimer dimensions themselves were studied in highly diluted polymer solutions, where no aggregation phenomena are present. Furthermore, micellar aggregates and their fraction increased going from dilute solutions to higher concentrations, finally adapting the discussed transient polymer networks. In order to enable fluorescence correlation spectroscopy investigations, a novel post-polymerization protocol for fluorescent dye attachment was established, which stands out by only a marginal alteration in the chemical nature of the labeled polymer. Chapter 7 emphasizes the concentration-dependent viscosity-temperature relationship of the (non)-hydrogenated tapered multiblock copolymers in the polyisoprene-selective solvents squalane and a highly isoparaffinic hydrocarbon lubricating oil against the background of the self-assembled structures discussed in Chapter 6. Combining temperature- and frequency- dependent dynamic viscosity measurements with temperature-dependent kinematic viscosity measurements at 40 °C and 100 °C, a clear correlation between the self-organized polymer aggregate structure and the performance as viscosity modifier could be established. At comparably low polymer concentrations, an enhanced viscosity-temperature relationship with increasing overall molar mass, block number, and isoprene content was identified. As an explanation, the formation of loose aggregates with several polystyrene cores and hence extended hydrodynamic volumes in case of multiblock architectures was deduced. Yet at high concentrations, the structures with the shortest individual solvophobic polystyrene blocks faced a deterioration in the investigated tribological key parameters, i.e., the viscosity- temperature relationship and the thickening efficiency. This is explained by the formation of large transient networks, which are more prone to partial disassembly upon shearing. This effect is further intensified by the migration of solvent molecules into the aggregate's cores, which is most pronounced for short polystyrene blocks. The resulting weakened van-der-Waals interactions promote chain pull-out and by this partial disassembly. Comparison of the investigated styrene-diene multiblock copolymers to a commercialized comb-like poly(alkyl methacrylate) displayed a superior performance of the presented structures at low polymer treat rates. This demonstrates the enormous potential of tapered multiblock architectures as advanced viscosity modifiers. Chapter 8 aims at understanding the structure-property relationships of multiblock copolymers with a defined or a gradual, albeit sharp block profile in dilute non-selective solution. For this purpose, series of sequential and tapered multiblock copolymers (IS)nI with molar masses ranging from 40-400 kg·mol-1 and block numbers of 3-13 were comprehensively characterized by complementary approaches. Subsequently, dilute solutions in toluene were systematically investigated, implementing classical scaling relationships between the hydrodynamic characteristics derived from analytical ultracentrifugation, intrinsic viscosity, and related experiments. Both rotational and translational diffusion experiments showed subtle differences in the polymer coil dimension and hence rigidity for polymer series with equal block number. For these homologous polymer series, a more rigid and hence expanded chain conformation for the sequential structures was deducible compared to their tapered analogues. Interestingly, the polymer series with different molar masses and block number, whose polymers featured equal degrees of polymerization per polystyrene block, did not comply with the classical scaling relationships. This demonstrates the influence of the block number on the solution properties even in non-selective solvents. Chapter 9 studies the polymerizability of rotationally constrained 1,3-dienes with a fixed cisoid or transoid geometry of the double bonds. Particularly, the reactivity in living anionic polymerization approaches in non-polar media is examined, whose mechanism is proposed to proceed via a coordinative mechanism. Theoretical simulation approaches of two new 1,3-diene monomers with a rigid, prescribed cisoid or transoid geometry in cyclohexane as a typical non-polar solvent are combined with synthetic and kinetic studies. Experimental observations correlated with the predicted reactivities and simulated reaction pathways, which showed that a cisoid geometry with in-plane double bonds is mandatory for propagation. Indeed, the cisoid diene was homo- as well as copolymerizable with isoprene, whereas the transoid diene lacked reactivity. The required ring distortion in case of the cyclic cisoid diene resulted in higher simulated activation barriers for the propagation step in comparison to the addition of the unrestricted common monomer isoprene. This was experimentally confirmed by real-time 1H NMR spectroscopic kinetic investigations, which evinced a gradient formation in statistical copolymerization experiments of the cisoid diene with isoprene, whose steepness became flattened upon temperature increase. Additionally, thermal characterization of the statistical copolymers revealed a weakened segregation strength for the tapered diblock copolymers with a smoother gradual distribution of the comonomers along the polymer chain. Chapter A1 comprises a complementary examination of the ultimate mechanical properties of the tapered star-shaped polyisoprene-polystyrene multiblock copolymers treated in Chapter 4. Two series of (SIS)4 multiblock copolymers varying in their comonomer ratio were compared to the linear SIS triblock copolymers representing the corresponding arm structures. While the star-shaped polymers with a lower isoprene content ordered into lamellae and therefore were stiffer and less elastic, the series with a higher isoprene content possessed morphologies with a continuous polyisoprene phase. Irrespective of the formed morphology, the star-shaped (SIS)4 architectures outperformed the corresponding linear SIS polymers with respect to their toughness and strain at break. Furthermore, selective catalytic hydrogenation of the PI blocks was exemplified for one star-shaped multiblock copolymer and its linear counterpart, this way increasing the segregation strength and decreasing the entanglement molecular weight of the polydiene segments. Interestingly, the influence of hydrogenation on the ultimate properties varied with the polymer architecture. While the linear tapered triblock copolymer experienced a substantial increase in its ultimate properties, the star-shaped multiblock copolymer faced a deteriorated performance. This is explained by differences in the magnitude of strain- hardening improvement in combination with higher amounts of entanglements. Chapter A2 focuses on the impact of solvents on the copolymerization kinetics of epoxides via an anionic ring-opening polymerization mechanism. For this purpose, the copolymerization kinetics of ethylene oxide (EO) with glycidyl ethers with varying coordination sites were monitored by in situ 1H NMR spectroscopy both in tetrahydrofuran (THF) and the highly polar solvent dimethyl sulfoxide (DMSO). The experiments revealed slightly higher reactivities of the glycidyl ethers compared to EO, which lacks in any side group, emphasizing a pronounced chelation effect of the potassium counterion by the side groups of the glycidyl ether monomers about to be added. With allyl glycidyl ether (AGE) featuring one and ethoxy vinyl glycidyl ether (EVGE) possessing two ether-type coordination sites per side group, EVGE showed slightly stronger incorporation preference than AGE. An increase in the disparity of the relative reactivities was found with decreasing solvent polarity, which relies on the degree of solvation of the propagating chain end and its counterion. Density functional theoretical simulation approaches were implemented to illustrate and further justify the pivotal role of the complexation capability of the ether-containing side groups.

Download or read book Sequence Controlled Polymers written by Jean-François Lutz and published by John Wiley & Sons. This book was released on 2018-04-09 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: Edited by a leading authority in the field, the first book on this important and emerging topic provides an overview of the latest trends in sequence-controlled polymers. Following a brief introduction, the book goes on to discuss various synthetic approaches to sequence-controlled polymers, including template polymerization, genetic engineering and solid-phase chemistry. Moreover, monomer sequence regulation in classical polymerization techniques such as step-growth polymerization, living ionic polymerizations and controlled radical polymerizations are explained, before concluding with a look at the future for sequence-controlled polymers. With its unique coverage of this interdisciplinary field, the text will prove invaluable to polymer and environmental chemists, as well as biochemists and bioengineers.

Download or read book Alternating Copolymers written by J.M.G. Cowie and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examination of the early literature attests to the fact that the study of copolymerization was initiated when polymer science was in its infancy. It has continued to grow to a subject of major importance and has been a source of interest to both academic and industrialist alike. The wide spectrum of structures and properties available in the statistical copolymer has made this a fruitful field of exploration, but one particular and more restricted form which has held its own fascination for many is the limiting case of the strictly alternating copolymer. This is formed, in the ideal situation, when two monomers in a reaction mixture add consecutively to create a polymer chain with a regular {ABABAB} structure, irrespective of the monomer feed ratio. When this happens the resulting copolymer will always have the same composition, a feature which can be advantageous but also somewhat restrictive, as the ability to vary the properties is then limited. Within a series entitled Speciality Polymers it seems appropriate then to deal with this subject, particularly as no previous attempt has been made to draw together the various facets of alternating copolymerization into one volume. It also seems timely to present a more unified picture of the subject which will also illustrate the progress made.

Download or read book Properties of Polymers written by D.W. van Krevelen and published by Elsevier. This book was released on 2012-12-02 with total page 898 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Science and Technology of Rubber written by James E. Mark and published by Elsevier. This book was released on 2011-07-28 with total page 762 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Science and Technology of Rubber, Third Edition provides a broad survey of elastomers with special emphasis on materials with a rubber-like elasticity. As in the 2nd edition, the emphasis remains on a unified treatment of the material; exploring topics from the chemical aspects such as elastomer synthesis and curing, through recent theoretical developments and characterization of equilibrium and dynamic properties, to the final applications of rubber, including tire engineering and manufacturing. Many advances have been made in polymer and elastomers research over the past ten years since the 2nd edition was published. Updated material stresses the continuous relationship between the ongoing research in synthesis, physics, structure and mechanics of rubber technology and industrial applications. Special attention is paid to recent advances in rubber-like elasticity theory and new processing techniques for elastomers. This new edition is comprised of 20% new material, including a new chapter on environmental issues and tire recycling.

Download or read book Synthesis and Applications of Copolymers written by Anbanandam Parthiban and published by John Wiley & Sons. This book was released on 2014-06-23 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the reactivity of monomers is crucial in creating copolymers and determining the outcome of copolymerization. Covering the fundamental aspects of polymerization, Synthesis and Applications of Copolymers explores the reactivity of monomers and reaction conditions that ensure that the newly formed polymeric materials exhibit desired properties. Referencing a wide-range of disciplines, the book provides researchers, students, and scientists with the preparation of a diverse variety of copolymers and their recent developments, with a particular focus on copolymerization, crystallization, and techniques like nanoimprinting and micropatterning.

Download or read book Principles of Polymerization written by George Odian and published by John Wiley & Sons. This book was released on 2004-02-09 with total page 850 pages. Available in PDF, EPUB and Kindle. Book excerpt: The new edition of a classic text and reference The large chains of molecules known as polymers are currently used in everything from "wash and wear" clothing to rubber tires to protective enamels and paints. Yet the practical applications of polymers are only increasing; innovations in polymer chemistry constantly bring both improved and entirely new uses for polymers onto the technological playing field. Principles of Polymerization, Fourth Edition presents the classic text on polymer synthesis, fully updated to reflect today's state of the art. New and expanded coverage in the Fourth Edition includes: * Metallocene and post-metallocene polymerization catalysts * Living polymerizations (radical, cationic, anionic) * Dendrimer, hyperbranched, brush, and other polymer architectures and assemblies * Graft and block copolymers * High-temperature polymers * Inorganic and organometallic polymers * Conducting polymers * Ring-opening polymer ization * In vivo and in vitro polymerization Appropriate for both novice and advanced students as well as professionals, this comprehensive yet accessible resource enables the reader to achieve an advanced, up-to-date understanding of polymer synthesis. Different methods of polymerization, reaction parameters for synthesis, molecular weight, branching and crosslinking, and the chemical and physical structure of polymers all receive ample coverage. A thorough discussion at the elementary level prefaces each topic, with a more advanced treatment following. Yet the language throughout remains straightforward and geared towards the student. Extensively updated, Principles of Polymerization, Fourth Edition provides an excellent textbook for today's students of polymer chemistry, chemical engineering, and materials science, as well as a current reference for the researcher or other practitioner working in these areas.

Download or read book Syndiotactic Polystyrene written by Jürgen Schellenberg and published by John Wiley & Sons. This book was released on 2009-10-29 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt: Syndiotactic Polystyrene (SPS), synthesized in a laboratory for the first time in 1985, has become commercialized in a very short time, with wide acceptance on the global plastics market. Written by leading experts from academia and industry from all over the world, Syndiotactic Polystyrene offers a comprehensive review of all aspects of SPS of interest to both science and industry, from preparation and properties to applications. This essential reference to SPS covers: The preparation of syndiotactic polystyrene by half-metallocenes and other transition metal catalysts The structure and fundamental properties, especially morphology and crystallization and solution behavior The commercial process for SPS manufacturing Properties, processing, and applications of syndiotactic polystyrenes Polymers based on syndiotactic polystyrenes, for example, by functionalization and modification, and nanocomposites Ideal for polymer chemists, physicists, plastics engineers, materials scientists, and all those dealing with plastics manufacturing and processing, this important resource provides the information one needs to compare, select, and integrate an appropriate materials solution for industrial use or research.

Download or read book Basic Fundamentals of Drug Delivery written by and published by Academic Press. This book was released on 2018-11-30 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt: Basic Fundamentals of Drug Delivery covers the fundamental principles, advanced methodologies and technologies employed by pharmaceutical scientists, researchers and pharmaceutical industries to transform a drug candidate or new chemical entity into a final administrable drug delivery system. The book also covers various approaches involved in optimizing the therapeutic performance of a biomolecule while designing its appropriate advanced formulation. - Provides up-to-date information on translating the physicochemical properties of drugs into drug delivery systems - Explores how drugs are administered via various routes, such as orally, parenterally, transdermally or through inhalation - Contains extensive references and further reading for course and self-study

Download or read book Nanotechnology Based Targeted Drug Delivery Systems for Lung Cancer written by Prashant Kesharwani and published by Academic Press. This book was released on 2019-01-26 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology-based Targeted Drug Delivery Systems for Lung Cancer is an indispensable resource that will help pharmaceutical scientists and clinical researchers design and develop novel drug delivery systems and devices for the treatment of lung cancer. As recent breakthroughs in nanomedicine are now making it possible to deliver drugs, genes and therapeutic agents to localized areas of disease to maximize clinical benefit, while also limiting unwanted side effects, this book explores promising approaches for the diagnosis and treatment of lung cancer using cutting-edge nanomedical technologies. Topics discussed include polymeric nanoparticles, solid lipid nanoparticles, liposomes, dendrimers, micelles and nanoemulsions. - Provides an overview of an array of nanotechnology-based drug delivery systems - Examines the design, synthesis and application of different nanocarriers in drug and gene delivery - Provides an in-depth understanding of the design of targeted nanotherapeutics and technologies and its implication in various site-specific cancers

Download or read book Cooperative Catalysis written by René Peters and published by John Wiley & Sons. This book was released on 2015-04-27 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by experts in the field, this is a much-needed overview of the rapidly emerging field of cooperative catalysis. The authors focus on the design and development of novel high-performance catalysts for applications in organic synthesis (particularly asymmetric synthesis), covering a broad range of topics, from the latest progress in Lewis acid / Br?nsted base catalysis to e.g. metal-assisted organo catalysis, cooperative metal/enzyme catalysis, and cooperative catalysis in polymerization reactions and on solid surfaces. The chapters are classified according to the type of cooperating activating groups, and describe in detail the different strategies of cooperative activation, highlighting their respective advantages and pitfalls. As a result, readers will learn about the different concepts of cooperative catalysis, their corresponding modes of operation and their applications, thus helping to find a solution to a specific synthetic catalysis problem.

Download or read book Regenerative Engineering of Musculoskeletal Tissues and Interfaces written by Syam Nukavarapu and published by Woodhead Publishing. This book was released on 2015-04-24 with total page 463 pages. Available in PDF, EPUB and Kindle. Book excerpt: Repair and regeneration of musculoskeletal tissues is generating substantial interest within the biomedical community. Consequently, these are the most researched tissues from the regeneration point of view. Regenerative Engineering of Musculoskeletal Tissues and Interfaces presents information on the fundamentals, progress and recent developments related to the repair and regeneration of musculoskeletal tissues and interfaces. This comprehensive review looks at individual tissues as well as tissue interfaces. Early chapters cover various fundamentals of biomaterials and scaffolds, types of cells, growth factors, and mechanical forces, moving on to discuss tissue-engineering strategies for bone, tendon, ligament, cartilage, meniscus, and muscle, as well as progress and advances in tissue vascularization and nerve innervation of the individual tissues. Final chapters present information on musculoskeletal tissue interfaces. - Comprehensive review of the repair and regeneration of musculoskeletal individual tissues and tissue interfaces - Presents recent developments, fundamentals and progress in the field of engineering tissues - Reviews progress and advances in tissue vascularization and innervation

Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2676 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Block Copolymers I written by Volker Abetz and published by Springer Science & Business Media. This book was released on 2005-12-02 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1 N. Hadjichristidis, M. Pitsikalis, H. Iatrou: Synthesis of Block Copolymers.- 2 V. Abetz: Phase Behaviour and Morphologies of Block Copolymers.-

Download or read book Anionic Polymerization written by Henry Hsieh and published by CRC Press. This book was released on 1996-03-15 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work introduces the basic theories and experimental methods of anionic polymerization as well as the synthesis, analysis and characteristics of anionic polymerized products. It details the creation of linear and branched polymers, random and block copolymers, graft and macromonomers, and many other substances. The work emphasizes the relationship between fundamental principles and commercial applications.;College or university bookstores may purchase five or more copies at a special student price, available on request from Marcel Dekker, Inc.

Download or read book Polymer Synthesis Theory and Practice written by Dietrich Braun and published by Springer Science & Business Media. This book was released on 2006-10-14 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first English edition of this book was pubUshed in 1971 with the late Prof. Dr. Werner Kern as coauthor. In 1997, for the preparation of the third edition, Prof. Dr. Helmut Ritter joined the team of authors and in 2001 Prof. Dr. Brigitte Voit and Prof. Dr. Matthias Rehahn complemented this team. The change in authors has not altered the basic concept of this 4th edition: again we were not aimed at compiling a comprehensive collection of recipes. In stead, we attempted to reach a broader description of the general methods and techniques for the synthesis, modification, and characterization of macromo- cules, supplemented by 105 selected and detailed experiments and by sufficient theoretical treatment so that no additional textbook be needed in order to under stand the experiments. In addition to the preparative aspects we have also tried to give the reader an impression of the relation of chemical structure and mor phology of polymers to their properties, as well as of areas of their application.

Download or read book Sterilisation of Biomaterials and Medical Devices written by Sophie Lerouge and published by Elsevier. This book was released on 2012-09-27 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effective sterilisation of any material or device to be implanted in or used in close contact with the human body is essential for the elimination of harmful agents such as bacteria. Sterilisation of biomaterials and medical devices reviews established and commonly used technologies alongside new and emerging processes.Following an introduction to the key concepts and challenges involved in sterilisation, the sterilisation of biomaterials and medical devices using steam and dry heat, ionising radiation and ethylene oxide is reviewed. A range of non-traditional sterilisation techniques, such as hydrogen peroxide gas plasma, ozone and steam formaldehyde, is then discussed together with research in sterilisation and decontamination of surfaces by plasma discharges. Sterilisation techniques for polymers, drug-device products and tissue allografts are then reviewed, together with antimicrobial coatings for 'self-sterilisation' and the challenge presented by prions and endotoxins in the sterilisation of reusable medical devices. The book concludes with a discussion of future trends in the sterilisation of biomaterials and medical devices.With its distinguished editors and expert team of international contributors, Sterilisation of biomaterials and medical devices is an essential reference for all materials scientists, engineers and researchers within the medical devices industry. It also provides a thorough overview for academics and clinicians working in this area. - Reviews established and commonly used technologies alongside new and emerging processes - Introduces and reviews the key concepts and challenges involved in sterilisation - Discusses future trends in the sterilisation of biomaterials and medical devices