Download or read book Studies of the Adsorption Characteristics of Amphiphilic Polymers on Surfaces written by Chiliang Larry Chen and published by . This book was released on 1996 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modification of Solid Surfaces Via Adsorption of Amphiphilic Polymers written by Sunil Manoharlal Dhoot and published by . This book was released on 1994 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coarse grained Molecular Modelling of Amphiphilic Polymers at a Water written by Khongvit Prasitnok and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous atomic-level simulations have been shown to provide invaluable insight into the adsorption behaviour of amphiphilic polymers at a water-air interface. Neutron reflectivity profiles generated from these simulations showed good agreement with experiment, particularly at low surface concentrations. Unfortunately, previous detailed atomistic simulations have failed to produce adequate results at high surface concentrations due to crowded configurations, which could not relax within the simulation times available. To tackle this problem, a coarse-graining (CG) technique, where the structure of the simulated molecule is simplified to a chain of beads, has been employed in this study. This provides for the simulation of larger time and length scales allowing for a more detailed study of the capture of polymer chains by a surface and the structure of surface layers. The work presented in this thesis involves development of coarse-grained models for water and for poly(ethylene oxide) (PEO)/water systems, with the aim of reproducing the properties of key importance for the bulk and liquid/vapour interfacial states. These models are then used in the coarse-grained simulation studies of di-and trifluoro dendritic end-capped PEO at an air-water interface; the amphiphilic polymers that have been studied recently by neutron reflectivity experiments. It is shown in this study that simulation of very large polymer chains comparable to that used in real experiments, is achievable using coarse-grained molecular dynamics. Neutron reflectivity profiles generated from simulations of di- and trifluoro dendritic end-capped PEO materials at low polymer concentrations are in good agreement with experiment data. Simulations at high polymer concentrations showed no evidence of a stretched brush structure, in accordance with experimental findings. It is shown from these simulations that there are polymers adsorbed to the interface by a combination of fluorocarbon ends and ethylene oxide segments,resulting in a rather at layer structure. At high surface concentrations of polymers, it proved possible to see the formation of polymer micelles in bulk water. The process of micelle capture by the surface and incorporation of the micelle contents into the surface, were also observed.
Download or read book Physicochemical Behavior and Supramolecular Organization of Polymers written by Ligia Gargallo and published by Springer Science & Business Media. This book was released on 2009-02-18 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the title suggests, this monograph features the physicochemical behavior and supramolecular organization of polymers. The book consists of four chapters dealing with solution properties, viscoelastic behavior, physicochemical aspects at interfaces and supramolecular structures of polymeric systems. The classical treatment of the physicochemical behavior of polymers is presented in such a way that the book will meet the requirements of a beginner in the study of polymeric systems in solution and in some aspects of the solid state, as well as those of the experienced researcher in other types of materials. Physicochemical behavior and Supramolecular Organization of Polymers is ultimately, a contribution to the chemistry of materials; it is a powerful reference tool for students and scientists working both in polymer chemistry, polymer physics and materials science.
Download or read book Characterization of the Molecular Structure and Mechanical Properties of Polymer Surfaces and Protein written by and published by . This book was released on 2004 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sum frequency generation (SFG) vibrational spectroscopy, atomic force microscopy (AFM), and other complementary surface-sensitive techniques have been used to study the surface molecular structure and surface mechanical behavior of biologically-relevant polymer systems. SFG and AFM have emerged as powerful analytical tools to deduce structure/property relationships, in situ, for polymers at air, liquid and solid interfaces. The experiments described in this dissertation have been performed to understand how polymer surface properties are linked to polymer bulk composition, substrate hydrophobicity, changes in the ambient environment (e.g., humidity and temperature), or the adsorption of macromolecules. The correlation of spectroscopic and mechanical data by SFG and AFM can become a powerful methodology to study and engineer materials with tailored surface properties. The overarching theme of this research is the interrogation of systems of increasing structural complexity, which allows us to extend conclusions made on simpler model systems. We begin by systematically describing the surface molecular composition and mechanical properties of polymers, copolymers, and blends having simple linear architectures. Subsequent chapters focus on networked hydrogel materials used as soft contact lenses and the adsorption of protein and surfactant at the polymer/liquid interface. The power of SFG is immediately demonstrated in experiments which identify the chemical parameters that influence the molecular composition and ordering of a polymer chain's side groups at the polymer/air and polymer/liquid interfaces. In general, side groups with increasingly greater hydrophobic character will be more surface active in air. Larger side groups impose steric restrictions, thus they will tend to be more randomly ordered than smaller hydrophobic groups. If exposed to a hydrophilic environment, such as water, the polymer chain will attempt to orient more of its hydrophilic groups to the surface in order to minimize the total surface energy. With an understanding of the structural and environmental parameters which govern polymer surface structure, SFG is then used to explore the effects of surface hydrophobicity and solvent polarity on the orientation and ordering of amphiphilic neutral polymers adsorbed at the solid/liquid interface. SFG spectra show that poly(propylene glycol) (PPG) and poly(ethylene glycol) (PEG) adsorb with their hydrophobic moieties preferentially oriented toward hydrophobic polystyrene surfaces. These same moieties, however, disorder when adsorbed onto a hydrophilic silica/water interface. Water is identified as a critical factor for mediating the orientation and ordering of hydrophobic moieties in polymers adsorbed at hydrophobic interfaces. The role of bulk water content and water vapor, as they influence hydrogel surface structure and mechanics, continues to be explored in the next series of experiments. A method was developed to probe the surface viscoelastic properties of hydroxylethyl methacrylate (HEMA) based contact lens materials by analyzing AFM force-distance curves. AFM analysis indicates that the interfacial region is dehydrated, relative to the bulk. Experiments performed on poly(HEMA+MA) (MA = methacrylic acid), a more hydrophilic copolymer with greater bulk water content, show even greater water depletion at the surface. SFG spectra, as well as surface energy arguments, suggest that the more hydrophilic polymer component (such as MA) is not favored at the air interface; this may explain anomalies in water retention at the hydrogel surface. Adsorption of lysozyme onto poly(HEMA+MA) was found to further reduce near-surface viscous behavior, suggesting lower surface water content. Lastly, protein adsorption is studied using a model polymer system of polystyrene covalently bound with a monolayer of bovine serum albumin. SFG results indicate that some amino acid residues in proteins adopt preferred orientations. SFG spectra also show that the phenyl rings of the bare polystyrene substrate in contact with air or liquid are ordered, with a dipole component directed along the surface normal, but slightly disorder after protein adsorption. Differences in AFM friction values suggest that protein interacts more strongly with the polystyrene substrate at the air/solid interface. The molecular orientation and ordering of surface phenyl groups are also shown to affect substrate hydrophobicity.
Download or read book Polymer Surfaces and Interfaces written by W. J. Feast and published by . This book was released on 1987-04-28 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: A collection of review papers which give an up-to-date interdisciplinary view of current technology and research on polymer surfaces. Contributors are drawn from both academia and industry, and represent a cross-section of subject interests.
Download or read book Amphiphilic Polymer Co networks written by Costas S Patrickios and published by Royal Society of Chemistry. This book was released on 2020-04-23 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amphiphilic polymer co-networks (APCNs) are a type of polymeric hydrogel, their hydrophobic polymer segments and hydrophilic components produce less aqueous swelling, giving better mechanical properties than conventional hydrogels. This new class of polymers is attracting increasing attention, resulting in further basic research on the system, as well as new applications. This book focuses on new developments in the field of APCNs, and is organised in four sections: synthesis, properties, applications and modelling. Co-network architectures included in the book chapters are mainly those deriving from hydrophobic macro-cross-linkers, representing the classical approach; however, more modern designs are also presented. Properties of interest discussed include aqueous swelling, thermophysical and mechanical properties, self-assembly, electrical actuation, and protein adsorption. Applications described in the book chapters include the use of co-networks as soft contact lenses, scaffolds for drug delivery and tissue engineering, matrices for heterogeneous biocatalysis, and membranes of controllable permeability. Finally, an important theory chapter on the modelling of the self-assembly of APCNs is also included. The book is suitable for graduate students and researchers interested in hydrogels, polymer networks, polymer chemistry, block copolymers, self-assembly and nanomaterials, as well as their applications in contact lenses, drug delivery, tissue engineering, membranes and biocatalysis.
Download or read book Handbook of Industrial Water Soluble Polymers written by Peter A. Williams and published by John Wiley & Sons. This book was released on 2008-04-15 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Natural and synthetic water soluble polymers are used in a wide range of familiar industrial and consumer products, including coatings and inks, papers, adhesives, cosmetics and personal care products. They perform a variety of functions without which these products would be significantly more expensive, less effective or both. Written for research, development and formulation chemists, technologists and engineers at graduate level and beyond in the fine and specialty chemicals, polymers, food and pharmaceutical industries, the Handbook of Industrial Water Soluble Polymers deals specifically with the functional properties of both natural and synthetic water soluble polymers. By taking a function based approach, rather than a “polymer specific” approach the book illustrates how polymer structure leads to effect, and shows how different polymer types can be employed to achieve appropriate product properties.
Download or read book Colloid polymer Interactions written by Paul Dubin and published by American Chemical Society. This book was released on 1993 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents experimental studies of kinetics, configuration, and hydrodynamic properties of adsorbed polymer chains at colloidal surfaces. Describes flocculation and stabilization of colloidal particles in solutions containing adsorbing or nonadsorbing uncharged polymers or polyelectrolytes. Highlights theoretical and computer simulation studies of the structure and dynamics of polymers adsorbed at interfaces. Discusses interactions of macromolecules with micelles, bilayers, liposomes, and proteins.
Download or read book Polymeric Biomaterials written by Severian Dumitriu and published by CRC Press. This book was released on 2013-01-17 with total page 920 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomaterials have had a major impact on the practice of contemporary medicine and patient care. Growing into a major interdisciplinary effort involving chemists, biologists, engineers, and physicians, biomaterials development has enabled the creation of high-quality devices, implants, and drug carriers with greater biocompatibility and biofunctiona
Download or read book Polymers in a Marine Environment written by Mukesh Doble and published by Smithers Rapra. This book was released on 2014-11-19 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers, plastics, and composite materials are widely used in the shipping industry and so get exposed to marine waters. Biofouling of these leads to problems for ships and boats in the form of reduced speed and corrosion, which these industries would like to prevent. Several hundred thousand tons of plastics that are discarded reach the marine environment every year either from land run-off or because of maritime activities. It has been estimated that because plastics do not degrade easily, one million marine animals are killed every year either by choking on floating plastic items or by becoming entangled in plastic debris. For the shipping industry the polymer should not foul and should be stable for extended periods of time in the marine environment. For the environmentalist the waste dumped after its use should degrade fast without causing problems to flora and fauna as well to the coastal economies. Addressing one of these issues leads to enhancement of the other issue and so this is not an easy problem to solve. This book covers the interaction of polymers with the marine environment, the problems they cause to ecology, their biofouling and biodegradation, and possible solutions.
Download or read book Surface Properties Volume 95 written by Ilya Prigogine and published by Wiley-Interscience. This book was released on 1996-08-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of surfaces has experienced dramatic growth over the past decade. Now, the editors of the internationally celebrated series Advances in Chemical Physics have brought together in this self-contained, special topic volume contributions from leading researchers in the field treating some of the most crucial aspects of the experimental and theoretical study of surfaces. This work delves into such core issues as: * Kinetics and dynamics of hydrogen adsorption on silicon surfaces. * Potential energy surfaces of transition- metal-catalyzed chemical reactions. * High-resolution helium atom scattering as a proof of surface vibrations. * Ordering and phase transitions in adsorbed monolayers of diatomic molecules. * The influence of dimensionality on static and dynamic properties of a system. * New applications to fields as varied as catalysts and the passage of molecules through membranes. This valuable resource provides important insights into the current state of knowledge about surface properties. Prigogine and Rice's latest work will stimulate the imagination and motivate the exploration of other aspects of this fascinating subject.
Download or read book Theoretical Studies of Adsorbed Polymers and Amphiphile Monolayers written by Jun Gao and published by . This book was released on 1993 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Azo Polymers written by Xiaogong Wang and published by Springer. This book was released on 2016-10-19 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores functional polymers containing aromatic azo chromophores in side-chain, main-chain and other parts of their structures, known as azo polymers and which share common photoresponsive properties. It focuses on the molecular architecture of azo polymers, the synthetic methods and their most important functions, such as photoinduced birefringence and dichroism, surface-relief-grating (SRG) formation, and light-driven deformation of liquid crystal elastomers. It combines a general survey of the subject and in-depth discussions of each topic, including numerous illustrations, figures, and photographs. Offering a balance between an introduction to the core concepts and a snapshot of hot and emerging topics, it is of interest to graduate students and researchers working in this and related fields. Xiaogong Wang is a Professor at the Department of Chemical Engineering, Tsinghua University, China.
Download or read book Encyclopedia of Surface and Colloid Science written by P. Somasundaran and published by CRC Press. This book was released on 2006 with total page 1148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Issues in Materials and Manufacturing Research 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 7150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Materials and Manufacturing Research: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Materials and Manufacturing Research. The editors have built Issues in Materials and Manufacturing Research: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Materials and Manufacturing Research in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Materials and Manufacturing Research: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Structure and Functional Properties of Colloidal Systems written by Roque Hidalgo-Alvarez and published by CRC Press. This book was released on 2009-11-18 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrating fundamental research with the technical applications of this rapidly evolving field, Structure and Functional Properties of Colloidal Systems clearly presents the connections between structure and functional aspects in colloid and interface science. It explores the physical fundamentals of colloid science, new developments of synthesis
