Download or read book Depletion Effects and Phase Behavior in Model Mixtures of Rod like Polymers and Colloidal Spheres written by Yeng-Long Chen and published by . This book was released on 2001 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Colloids and the Depletion Interaction written by Henk N. W. Lekkerkerker and published by Springer Nature. This book was released on with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mixtures of Colloidal Rods and Spheres in Bulk and in Confinement written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: When non-adsorbing polymers are added to an isotropic suspension of rod-like colloids, the colloids effectively attract each other via depletion forces. Monte Carlo simulations were performed to study the phase diagram of such rod-polymer mixtures. The colloidal rods were modelled as hard spherocylinders; the polymers were described as spheres of the same diameter as the rods. The polymers may overlap with no energy cost, while overlap of polymers and rods is forbidden. In this thesis the emphasis was on the depletion effects caused by the addition of spheres on the isotropic phase of rod-like particles. Although most of the present experimental studies consider systems close to or beyond the isotropic-nematic transition, the isotropic phase with depletion interactions turns out to be a not less interesting topic. First, the percolation problem was studied in canonical simulations of a system of hard rods and soft spheres, where the amount of depletant was kept low to prevent phase separation of the mixture. The lowering of the percolation threshold seen in experiment is confirmed to be due to the depletion interactions. The local changes in the structure of the fluid of rods, which were measured in the simulations, indicated that the depletion forces enhance local alignment and aggregation of the rods. Then, the phase diagram of isotropic-isotropic demixing of short spherocylinders was calculated using grand canonical ensemble simulations with successive umbrella sampling. Finite size scaling analysis allowed to estimate the location of the critical point. Also, estimates for the interfacial tension between the coexisting isotropic phases and analyses of its power-law behaviour on approach of the critical point are presented. The obtained phase diagram was compared to the predictions of the free volume theory. After an analysis of the bulk, the phase behaviour in confinement was studied. The critical point of gas-liquid demixing is shifted to higher concentrations.
Download or read book Colloids and the Depletion Interaction written by Henk N.W. Lekkerkerker and published by Springer Science & Business Media. This book was released on 2011-05-12 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloids are submicron particles that are ubiquitous in nature (milk, clay, blood) and industrial products (paints, drilling fluids, food). In recent decades it has become clear that adding depletants such as polymers or small colloids to colloidal dispersions allows one to tune the interactions between the colloids and in this way control the stability, structure and rheological properties of colloidal dispersions. This book offers a concise introduction to the fundamentals of depletion effects and their influence on the phase behavior of colloidal dispersions. Throughout the book, conceptual explanations are accompanied by experimental and computer simulation results. From the review by Kurt Binder: "They have succeeded in writing a monograph that is a very well balanced compromise between a very pedagogic introduction, suitable for students and other newcomers, and reviews of the advanced research trends in the field. Thus each chapter contains many and up to date references, but in the initial sections of the chapters, there are suggested exercises which will help the interested reader to recapitulate the main points of the treatment and to deepen his understanding of the subject. Only elementary knowledge of statistical thermodynamics is needed as a background for understanding the derivations presented in this book; thus this text is suitable also for advanced teaching purposes, useful of courses which deal with the physics for soft condensed matter. There does not yet exist any other book with a similar scope..... The readability of this book is furthermore enhanced by a list of symbols, and index of keywords, and last not least by a large number of figures, including many pedagogic sketches which were specifically prepared for this book. Thus, this book promises to be very useful for students and related applied sciences alike." Eur. Phys. J. E (2015) 38: 73
Download or read book A Mechanistic Understanding of the Polymer induced Phase Behavior of Colloidal scale Suspensions written by Naa Larteokor McFarlane and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The phase behavior of model polymer - colloid mixtures is measured in the "protein limit", i.e., when the radius of gyration of the polymer (R g) is greater than or approximately equal to the radius of the colloid (R) and in the "colloid limit" (R> R g). In this work, alumina-covered silica nanoparticles are mixed with poly (ethylene oxide) (PEO) or poly (vinyl pyrolidone) (PVP) at asymmetry ratios of R g /R = 0.7 and 1.8. The adsorption of the two polymers onto the cationic nanoparticles was measured using isothermal titration calorimetry (ITC), gravimetric methods, and dynamic light scattering. Addition of PEO to stable nanoparticle dispersions leads to phase separation by depletion flocculation in both deionized water and buffer solutions. The phase separation mechanism for the PVP - nanoparticle system depends on the suspension medium. In water, bridging induced separation occurs below the saturation adsorption of PVP; above surface saturation, mixing leads to depletion-induced separation. In acidic buffer, phase separation results from depletion-induced interactions. ITC measurements of the heats of adsorption unambiguously determine the effects of polymer type and added buffer solution on the stability of nanoparticle dispersions upon the addition of adsorbing polymer. We find weak segmental adsorption energies of ~0.2 k B T for PEO in water and buffer, consistent with the observed phase separation. For PVP in water, segmental adsorption energies of order ~1.6 k B T support bridging flocculation in water, whereas a weaker adsorption energy of ~0.7 k B T in buffer is consistent with a lack of significant bridging flocculation. The difference between bridging and depletion is distinguished by visual appearance, rheological measurements, and small-angle neutron scattering (SANS). SANS measurements of PVP phase separated samples show a loss of the fractal region at low wavevector with increasing polymer concentration in moving from bridge flocculated to the depletion phase separation regime. There was also a concurrent shift in the interaction peak to lower Q values. These two effects signify a decrease in the density of the fractal aggregates with changing phase separation mechanism, consistent with a shift from bridging flocculation to depletion attraction. The ratio of polymer concentration to polymer entanglement concentration (c/c*) required to induce phase separation increases with increasing R g /R in agreement with theoretical predictions of the polymer reference interaction site model (PRISM). This trend opposes classical depletion theories because the classical theories do not account for polymer entanglement, amongst others, by assuming non-interacting polymers that interact as hard spheres. This assumption is clearly violated when R g> R when the nanoparticles can interpenetrate the polymer coils. Cationic nanovesicles are formed by sonication and characterized by viscometry, dynamic light scattering, and small-angle neutron scattering. The phase behavior of PVP - nanovesicle mixtures are measured and compared to the cationic nanoparticle system. Unlike the colloids, the nanovesicles do not phase separate on a short time scale, but rather, become unstable and revert back to the birefringent lamellae structure due to electrostatic repulsion of the charged heard groups. The rate of this coalescence is enhanced by the addition of polymer. This work provides a complete data set exploring bridging flocculation and depletion induced phase separation in the protein limit. As such it can be used to test theoretical work and to provide guidance in formulating polymer - nanoparticle mixtures. Extension to systems of nanovesicles highlights the differences inherent in selfassembled systems as compared to nanoparticles. The results can help guide industrial formulations containing mixtures of polymer, nanoparticles, and surfactant mesophases.
Download or read book Phase Behaviour of Proteins and Colloid Polymer Mixtures written by Christoph Gögelein and published by Forschungszentrum Jülich. This book was released on 2008 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling Polymer colloid Phase Behavior written by Naa Larteokor Quarcoo and published by . This book was released on 2007 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, we investigate the phase behavior of silica colloids in solution with two uncharged polymers, polyethylene oxide (PEO) and polyvinylpyrrolidone (PVP), with the values of Rg/R = 0.7 and 1.8 for each polymer. The four observed phase boundaries are related to the polymer characteristics of Rg and entanglement concentration (c*). The polymer properties were characterized by viscometry, light scattering and size exclusion chromatography. The experimental observations suggest that phase separation depends on the ratio of the polymer concentration to the entanglement concentration for a given polymer.
Download or read book The Oxford Handbook of Soft Condensed Matter written by Eugene M. Terentjev and published by OUP Oxford. This book was released on 2015-02-26 with total page 605 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soft condensed matter is a relatively new topic. Condensed matter has typically referred to more traditional liquids, which have a long history of study, or to solids, which have focused more commonly on hard materials, driven in large measure by the importance of structural materials or the metals and semiconductors which drove the rapid evolution of microelectronics. It is only relatively recently, over the past 20 to 30 years, that soft condensed matter has matured into its own identifiable field. However, the field is an amalgam of many subfields, and many of these have themselves much longer histories. This handbook serves as an overview of many of these topics. Because of the great breadth, it is impossible to include them all; nevertheless, the key subjects of soft condensed matter are represented here. Together, they form both an introduction and an overview of the field. Each topic, and its representing Chapter, could have been a full size book - in fact, there are a number of such books on many of the topics covered in the handbook. Our aim here was to give a current snapshot of the field, identify the key principles at play and the most prominent (and promising) ways of its further development, provide essential references for anyone to follow the subject, but not necessarily go into a lot of detail on each topic.
Download or read book Physical Review written by and published by . This book was released on 1998-07 with total page 1220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publishes papers that report results of research in statistical physics, plasmas, fluids, and related interdisciplinary topics. There are sections on (1) methods of statistical physics, (2) classical fluids, (3) liquid crystals, (4) diffusion-limited aggregation, and dendritic growth, (5) biological physics, (6) plasma physics, (7) physics of beams, (8) classical physics, including nonlinear media, and (9) computational physics.
Download or read book Theory and Applications of Colloidal Suspension Rheology written by Norman J. Wagner and published by Cambridge University Press. This book was released on 2021-04-15 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essential text on the practical application and theory of colloidal suspension rheology, written by an international coalition of experts.
Download or read book Nanoscience written by Victor M. Starov and published by CRC Press. This book was released on 2011-06-03 with total page 1610 pages. Available in PDF, EPUB and Kindle. Book excerpt: The common perception is that nanoscience is something entirely new, that it sprung forth whole and fully formed like some mythological deity. But the truth is that like all things scientific, nanoscience is the natural result of the long evolution of scientific inquiry. Following a historical trail back to the middle of the 19th century, nanoscience is the inborn property of colloid and interface science. What’s important today is for us to recognize that nanoparticles are small colloidal objects. It should also be appreciated that over the past decades, a number of novel nanostructures have been developed, but whatever we call them, we cannot forget that their properties and behavior are still in the realm of colloid and interface science. However one views it, the interest and funding in nano-science is a tremendous opportunity to advance critical research in colloid chemistry. Nanoscience: Colloidal and Interfacial Aspects brings together a prominent roster of 42 leading investigators and their teams, who detail the wide range of theoretical and experimental knowledge that can be successfully applied for investigating nanosystems, many of which are actually well-known colloidal systems. This international grouping of pioneering investigators from academia and industry use these pages to provide researchers of today and tomorrow with a full examination of nano-disperse colloids, homogeneous and heterogeneous nano-structured materials (and their properties), and shelf-organization at the nano-scale. This cutting-edge reference provides information on investigations into non-linear electrokinetic phenomena in nano-sized dispersions and nano-sized biological systems. It discusses application aspects of technological processes in great detail, providing scientists and engineers across all fields with authoritative commentary on colloid and interface science operating at the nanoscale. Nano-Science: Colloidal and Interfacial Aspects provides an authoritative resource for those wanting to familiarize themselves with current progress as well as for those looking to make their own impact on the development of new technologies and practical applications in fields as diverse as medicine, materials, and environmental science to name but a few. Whether you call the technology nano or colloids, the field continues to be ripe with opportunity.
Download or read book Soft Matter at Aqueous Interfaces written by Peter Lang and published by Springer. This book was released on 2015-12-24 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the science of interfaces between an aqueous phase and a solid, another liquid or a gaseous phase, starting from the basic physical chemistry all the way to state-of-the-art research developments. Both experimental and theoretical methods are treated thanks to the contributions of a distinguished list of authors who are all active researchers in their respective fields. The properties of these interfaces are crucial for a wide variety of processes, products and biological systems and functions, such as the formulation of personal care and food products, paints and coatings, microfluidic and lab-on-a-chip applications, cell membranes, and lung surfactants. Accordingly, research and expertise on the subject are spread over a broad range of academic disciplines and industrial laboratories. This book brings together knowledge from these different places with the aim of fostering education, collaborations and research progress.
Download or read book Soft Matter Volume 2 written by Gerhard Gompper and published by John Wiley & Sons. This book was released on 2006-02-10 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soft Matter encompasses a wide range of systems of varying components, including synthetic and biological polymers, colloids, and amphiphiles. The distinguishing features of these systems is their characteristic size, which is much larger than that of their atomic counterparts, and their characteristic energy, which is much smaller. Because of their ability to assemble themselves into complex structures, they form the major components of biological systems and technological applications. This second volume of the unique interdisciplinary "Soft Matter" series comprehensively describes colloids and their properties. The structural and thermodynamic properties of mixtures of rod-like and spherical colloids and of mixtures colloids and polymers, as well as the dynamical behavior of rod-like colloids are treated in depth. Again leading scientists have contributed articles that both introduce readers to this field, and serve as a source of reference for experts.
Download or read book Product Design and Engineering written by Ulrich Bröckel and published by John Wiley & Sons. This book was released on 2013-08-02 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering the whole value chain - from product requirements and properties via process technologies and equipment to real-world applications - this reference represents a comprehensive overview of the topic. The editors and majority of the authors are members of the European Federation of Chemical Engineering, with backgrounds from academia as well as industry. Therefore, this multifaceted area is highlighted from different angles: essential physico-chemical background, latest measurement and prediction techniques, and numerous applications from cosmetic up to food industry. Recommended reading for process, pharma and chemical engineers, chemists in industry, and those working in the pharmaceutical, food, cosmetics, dyes and pigments industries.
Download or read book Polymer Colloids written by Rodney Priestley and published by Royal Society of Chemistry. This book was released on 2019-12-02 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Academic and industrial research around polymer-based colloids is huge, driven both by the development of mature technologies, e.g. latexes for coatings, as well as the advancement of new materials and applications, such as building blocks for 2D/3D structures and medicine. Edited by two world-renowned leaders in polymer science and engineering, this is a fundamental text for the field. Based on a specialised course by the editors, this book provides the reader with an invaluable single source of reference. The first section describes formation, explaining basic properties of emulsions and dispersion polymerization, microfluidic approaches to produce polymer-based colloids and formation via directed self-assembly. The next section details characterisation methodologies from microscopy and small angle scattering, to surface science and simulations. The final chapters close with applications, including Pickering emulsions and molecular engineering for materials development. A comprehensive guide to polymer colloids, with contributions by leaders in their respective areas, this book is a must-have for researchers and practitioners working across polymers, soft matter and chemical and molecular engineering.
Download or read book Observation Prediction and Simulation of Phase Transitions in Complex Fluids written by Marc Baus and published by Springer. This book was released on 1995-03-31 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt: Observation, Prediction and Simulation of Phase Transitions in Complex Fluids presents an overview of the phase transitions that occur in a variety of soft-matter systems: colloidal suspensions of spherical or rod-like particles and their mixtures, directed polymers and polymer blends, colloid--polymer mixtures, and liquid-forming mesogens. This modern and fascinating branch of condensed matter physics is presented from three complementary viewpoints. The first section, written by experimentalists, emphasises the observation of basic phenomena (by light scattering, for example). The second section, written by theoreticians, focuses on the necessary theoretical tools (density functional theory, path integrals, free energy expansions). The third section is devoted to the results of modern simulation techniques (Gibbs ensemble, free energy calculations, configurational bias Monte Carlo). The interplay between the disciplines is clearly illustrated. For all those interested in modern research in equilibrium statistical mechanics.
Download or read book Smart Colloidal Materials written by Walter Richtering and published by Springer Science & Business Media. This book was released on 2006-07-10 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains selected papers presented at the 42nd Biennial Meeting of the Kolloid-Gesellschaft held at the RWTH Aachen University September 26-28, 2005. The contributions in this volume represent the diversity of research topics in colloid and polymer science. They include the investigation of synthesis and properties of advanced temperature sensitive particles and their biomedical applications, drug delivery systems, foams, capsules, vesicles and gels, polyelectrolytes, nanoparticles surfactants and hybrid materials.
