Download or read book Interactions Between Polyelectrolytes on a Surface in Aqueous Solutions and Nanocomposites written by Sandrine Lteif and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interactions of charged polymers, polyelectrolytes, on surfaces and in solution have gained a lot of attention throughout the years. Depositing alternating layers of oppositely charged polyelectrolytes forms multilayers, PEMUs. Their association in solution leads to phase separations forming materials termed polyelectrolyte complexes, PECs. The repeat unit of the oppositely charged polyelectrolyte can be varied. The functional group linked to the repeat units dictates the strength of ion pairing. Their self-assembly in solution creates polymer nanoparticles and, in a network, produces polymer nanocomposites. These materials have been used for a variety of applications such as coatings, electronic devices, and drug delivery systems. Adding a certain salt concentration to the material can influence the polymer/polymer interaction within the complex. This work features three main interfaces at which polyelectrolyte interactions were studied: on a substrate through PEMUs, in solution through polymer nanoparticles and in nanocomposites. The pairing strength of a polythiouronium polyelectrolyte having a positively charged thiouronium group, like the guanidinium, was evaluated by the formation of PEMUs at various salt concentrations. Polyguanidiniums such as polyarginine are known to form like-charge ion pairings and hydrogen bonding. The same unusual characteristics cause the strong interactions of the polythiouronium with polyanions. High concentrations of salt dissociated the strong polythiouronium/polyanions complexes. The polythiouronium was selected to seek another example of a strong polycation and to form a PEMU with polyzwitterions, which are known for their weakly interacting strength and net-neutral charge. The second interface consists of the self-assembly of a polydimethylsiloxane (PDMS) with positively charged end groups in solution, and as a nanofiller, in a nanocomposite. Polydimethylsiloxane is biocompatible and highly hydrophobic; however, when self-assembled exhibits poor stability and tends to collapse. Introducing a glassy shell of polystyrene sulfonate enhances the stability of these polymer nanoparticles and improves the mechanical properties of the nanocomposite which exhibited thermal resistance. Using x-ray scattering and atomic force microscopy, the nanocomposite's unique morphology was deduced. Its hydrophobic properties were probed using a solvatochromic dye and were used to encapsulate inorganic nanoparticles. The gold nanoparticles are hydrophobically capped and they appeared to be encapsulated within the PDMS core. Their assembly was studied by x-ray scattering in the presence of a PSS shell in solution and the loading capability of the nanoparticle was determined by transmission electron microscopy (TEM). The newly formed material is a novel polymer nanoparticle/polymer nanocomposite that takes advantage of the PDMS malleability and biocompatibility. The nanoparticle can thus be used for biological applications such as bio-imaging and sensing. The last section compares the interactions of different polycations with lipid layers (monolayer or bilayer) to mimic the mechanism of surface sterilization. The functional group varied between a primary or tertiary ammonium, a guanidinium and two different thiouronium groups. Ammoniums are known for their ability to disrupt lipid bilayers and for their use in disinfectants. Polyarginine, a strong positively charged polymer, is recognized for its cell-penetrating ability due to its unique salt-bridge like interactions. Radioactive unilamellar phosphocholine vesicles were prepared and used to deposit a monolayer on a hydrophobic scintillator and a bilayer on a hydrophilic one. The interactions of the layers and the deposition were monitored by radiocounting. Polyarginine and the polymer with a higher composition of a hydrophobic thiouronium exhibited the strongest interactions. These investigations of the interactions between polyelectrolytes at different interfaces serve as a guide to design a variety of functional materials. Understanding the structure-property polymer relationship allows the build-up of materials with tuned properties.

Download or read book Surface Attached Polyelectrolyte Networks and Their Interaction with Charged Molecules in Aqueous Solutions written by Marcel Rothfelder and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Composites from Renewable Materials Nanocomposites written by Vijay Kumar Thakur and published by John Wiley & Sons. This book was released on 2017-03-28 with total page 738 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique multidisciplinary 8-volume set focuses on the emerging issues concerning synthesis, characterization, design, manufacturing and various other aspects of composite materials from renewable materials and provides a shared platform for both researcher and industry. The Handbook of Composites from Renewable Materials comprises a set of 8 individual volumes that brings an interdisciplinary perspective to accomplish a more detailed understanding of the interplay between the synthesis, structure, characterization, processing, applications and performance of these advanced materials. The Handbook comprises 169 chapters from world renowned experts covering a multitude of natural polymers/ reinforcement/ fillers and biodegradable materials. Volume 7 is solely focused on the "Nanocomposites: Science and Fundamentals" of renewable materials. Some of the important topics include but not limited to: Preparation, characterization, and applications of nanomaterials from renewable resources; hydrogels and its nanocomposites from renewable resources: preparation of chitin-based nanocomposite materials through gelation with ionic liquid; starch-based bionanocomposites; biorenewable nanofiber and nanocrystal; investigation of wear characteristics of dental composite reinforced with rice husk-derived nanosilica filler particles; performance of regenerated cellulose/vermiculite nanocomposites fabricated via ionic liquid; preparation, structure, properties, and interactions of the PVA/cellulose composites; green composites with cellulose nanoreinforcements; biomass composites from bamboo-based micro/nanofibers; synthesis and medicinal properties of polycarbonates and resins from renewable sources; nanostructured polymer composites with modified carbon nanotubes; organic–inorganic nanocomposites derived from polysaccharides; natural polymer-based nanocomposites; cellulose whisker-based green polymer composites; poly (lactic acid) nanocomposites reinforced with different additives; nanocrystalline cellulose; halloysite-based bionanocomposites; nanostructurated composites based on biodegradable polymers and silver nanoparticles; starch-based biomaterials and nanocomposites; green nanocomposites based on PLA and natural organic fillers; and chitin and chitosan-based nanocomposites.

Download or read book Physical Chemistry of Polyelectrolytes written by Tsetska Radeva and published by CRC Press. This book was released on 2001-02-21 with total page 910 pages. Available in PDF, EPUB and Kindle. Book excerpt: An examination of the fundamental nature of polyelectrolytes, static and dynamic properties of salt-free and salt-added solutions, and interactions with other charged and neutral species at interfaces with applications to industry and medicine. It applies the Metropolis Monte Carlo simulation to calculate counterion distributions, electric potentials, and fluctuation of counterion polarization for model DNA fragments.

Download or read book Interactions of Polyelectrolytes in Dilute Aqueous Solutions written by Leon Mir and published by . This book was released on 1963 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Polyelectrolytes and Their Applications Polyelectrolyte based multilayers self assemblies and nanostructures written by Sukant K. Tripathy and published by . This book was released on 2002 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multilayer Thin Films written by Gero Decher and published by Wiley-VCH. This book was released on 2003-03-07 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polyelectrolyte multilayers, an Overview; Fundamentals of polyelectrolyte complexes in solution and the bulk; Polyelectrolyte adsorption and multilayer formation; Charge balance and transport in polyelectrolyte multilayers; Ph- controlled fabrication of polyelectrolyte multilayers: assembly and applications; Recent progress in the surface sol-gel process and protein multilayers; Internally structured polyelectrolyte multilayers; Layer-by-layer assembly of nanoparticles and nanocolloids: intermolecular interactions, structure and materials perspectives; Layer-by-layer self assembled polyelectrolytes and nanoplatelets; Chemistry directed deposition via electrostatic and secondary interactions: a nonlithographic approach to patterned polyelectrolyte multilayer systems; Layered nanoarchitetures based on electro and photo active building blocks: Coated colloids; Smart capsules; Multilayers on solid planar substrates: from structure to function; Functional layer-by-layer assemblies with photo and electrochemical response and selective transport of small molecules and ions; self-assembled and characterization of electro optic materials; Controlling the ion permeability of layered polyelectrolyte films and membranes.

Download or read book Eco friendly Polymer Nanocomposites written by Vijay Kumar Thakur and published by Springer. This book was released on 2015-06-22 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains precisely referenced chapters, emphasizing environment-friendly polymer nanocomposites with basic fundamentals, practicality and alternatives to traditional nanocomposites through detailed reviews of different environmental friendly materials procured from different resources, their synthesis and applications using alternative green approaches. The book aims at explaining basics of eco-friendly polymer nanocomposites from different natural resources and their chemistry along with practical applications which present a future direction in the biomedical, pharmaceutical and automotive industry. The book attempts to present emerging economic and environmentally friendly polymer nanocomposites that are free from side effects studied in the traditional nanocomposites. This book is the outcome of contributions by many experts in the field from different disciplines, with various backgrounds and expertises. This book will appeal to researchers as well as students from different disciplines. The content includes industrial applications and will fill the gap between the research works in laboratory to practical applications in related industries.

Download or read book Interaction of Polyelectrolytes and Highly Charged Small Ions in Aqueous Solutions written by Stephen G. Pasternack and published by . This book was released on 2001 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interaction of Polyelectrolytes and Highly Charged Small Ions in Aqueous Solutions written by Stephen G. Pasternack and published by . This book was released on 1974 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Polymer graphene Nanocomposites written by Vikas Mittal and published by Royal Society of Chemistry. This book was released on 2012 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an important handbook for anyone wishing to get a comprehensive view of graphene nanocomposites and bring established methodologies into their laboratory.

Download or read book Metallopolymer Nanocomposites written by A.D. Pomogailo and published by Springer Science & Business Media. This book was released on 2006-01-27 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents and analyzes the essential data on nanoscale metal clusters dispersed in, or chemically bonded with polymers. Special attention is paid to the in situ synthesis of the nanocomposites, their chemical interactions, and the size and distribution of the particles in the polymer matrix. Numerous novel nanocomposites are described with regard to their mechanical, electrophysical, optical, magnetic, catalytic and biological properties. Their applications, present and future, are outlined.

Download or read book Graphene Science Handbook Six Volume Set written by Mahmood Aliofkhazraei and published by CRC Press. This book was released on 2016-04-26 with total page 3379 pages. Available in PDF, EPUB and Kindle. Book excerpt: Graphene is the strongest material ever studied and can be an efficient substitute for silicon. This six-volume handbook focuses on fabrication methods, nanostructure and atomic arrangement, electrical and optical properties, mechanical and chemical properties, size-dependent properties, and applications and industrialization. There is no other major reference work of this scope on the topic of graphene, which is one of the most researched materials of the twenty-first century. The set includes contributions from top researchers in the field and a foreword written by two Nobel laureates in physics. Volumes in the set: K20503 Graphene Science Handbook: Mechanical and Chemical Properties (ISBN: 9781466591233) K20505 Graphene Science Handbook: Fabrication Methods (ISBN: 9781466591271) K20507 Graphene Science Handbook: Electrical and Optical Properties (ISBN: 9781466591318) K20508 Graphene Science Handbook: Applications and Industrialization (ISBN: 9781466591332) K20509 Graphene Science Handbook: Size-Dependent Properties (ISBN: 9781466591356) K20510 Graphene Science Handbook: Nanostructure and Atomic Arrangement (ISBN: 9781466591370)

Download or read book Hybrid Nanocomposites for Nanotechnology written by Lhadi Merhari and published by Springer Science & Business Media. This book was released on 2009-03-03 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the latest advances in polymer-inorganic nanocomposites, with particular focus on high-added-value applications in fields including electronics, optics, magnetism and biotechnology. The unique focus of this book is on electronic, optical, magnetic and biomedical applications of hybrid nanocomposites. Coverage includes: Synthesis methods and issues and production scale-up; Characterization methods; Electronic applications; Optical applications and Photonics; Magnetic applications; and Biomedical applications. The book offers readers a solid grasp of the state of the art, and of current challenges in non-traditional applications of hybrid nanocomposites.

Download or read book The Interaction Between Polyelectrolytes and Surfaces written by Chung Yin Kong and published by . This book was released on 2001 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Layered Double Hydroxide Polymer Nanocomposites written by Sabu Thomas and published by Woodhead Publishing. This book was released on 2019-11-28 with total page 886 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanocomposites based on layered double hydroxides (LDHs) have recently become a formidable research area due to their amendable properties and potential applications. The distinct properties of LDH polymer nanocomposites include a wide range of chemical compositions, structural homogeneity, unique anion exchanging ability, easy synthesis, high bound water content, memory effect, non-toxicity and biocompatibility. This means that LDH polymer nanocomposites have the potential for new and innovative applications. Layered Double Hydroxide Polymer Nanocomposites presents a comprehensive overview of the recent innovative advances in the fabrication, characterization and applications of LDH polymer nanocomposites. As well as covering fundamental structural and chemical knowledge, this book also explores various properties and characterization techniques including microscopic, spectroscopic and mechanical behaviors. There is also a strong focus on the potential applications of LDH polymer nanocomposites, such as energy, electrical and electronic, electromagnetic shielding, biomedical, agricultural, food packaging and water purification functions. This book provides comprehensive coverage of cutting-edge research in the field of LDH polymer nanocomposites and their future applications. This book will be an essential read for all academics, researchers, engineers and students working in this area. Fundamental knowledge of LDH polymer nanocomposites, including chemical composition, structural features and fabrication techniques Provides an analytical overview of the different types of characterization techniques and technologies Extensive review on cutting-edge research for potential future applications, in a variety of industries

Download or read book Cellulose Interaction with Cationic Polyelectrolyte written by Jielong Su and published by . This book was released on 2015 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paper engineering of strength, structure and surface using interactions between cellulose and cationic polyelectrolytes are investigated with the aim of improving paper-based bio-analytical devices (PADs). Advances are described based on fundamental knowledge and engineering aspects in this field that have enable the development of lighter weight papers that have high wet strengths, controlled porosities and multi-functional properties that can be fine tuned.The influence of reactive cationic polyelectrolyte, polyamideamine-epichlorohydrin (PAE) on paper strength behaviour was studied using hardwood fibers, both with and without inorganic electrolyte. Ion type and concentration in the papermaking process water was found to influence the strength development in different ways. The relationship between repulpability of PAE- strengthened paper and wet strength is described. The effect of blending microfibrillated cellulose (MFC) with hardwood fibers is compared with the refining of hardwood fibers on paper composite properties, with and without PAE addition. Papers incorporating tethered MFC, produced by refining of hardwood fibres, are found to provide equivalent strength properties to papers incorporating untethered MFC with significant drainage benefits and formation uniformity. Air permeability of the composites decreases with untethered and tethered MFC addition.MFC achieved by ball milling and cellulose micro-particles (CMPs) developed by cryogenic milling softwood fiber are compared with commercial MFC produced by homogenization. The effect of blending two MFCs and CMPs with hardwood fibers on the paper composites properties is investigated in terms of nano/micro cellulose dimensions. CMPs act as mechanical debonding agents and decrease substrate density and strength whereas MFC have higher aspect ratios and smaller size distributions that significantly improve strength and density of composite sheets while decreasing porosities. The addition of MFC combined with PAE can increase both dry and wet strength. The different stress-strain curves under wet conditions are described and these suggest two different mechanisms of strength development: MFC-fiber entanglement and fiber-fiber contact reinforcement.The role of paper macroscale properties and structure are described in PADs used to type human red blood cells (RBCs). A series of commercial and laboratory-generated papers varying in fibre composition, basis weight, density and porosity are studied and their abilities to separate antibody agglutinated (specific) from non-agglutinated (non-specific) RBCs are reported. Image analysis is used to measure the intensities of blood spots produced by sequentially absorbing solutions of antibodies and blood samples on paper then eluting with a saline solution. The performance of these papers in blood typing is found to decrease linearly with paper density and thickness and it is inversely proportional to paper pore size. The type of fibres plays a minor role. Porous cellulose webs modified with cationic polyelectrolyte further optimize blood typing analysis.Cellulose model surfaces, in the form of quasi molecularly smooth thin cellulose films, are investigated to examine the interactions between cellulose, cationic polyelectrolytes and biomolecules. Thin smooth cellulose films are prepared by spin coating either a nanocellulose crystal suspension, or a cellulose acetate solution onto silicon surfaces with subsequent hydrolysis. Film smoothness is greatly improved by controlling the concentration of cellulose acetate and the hydrolysis time in methanolic sodium methoxide. High molecular weight polyacrylamides (CPAM) are used as model polyelectrolytes, and the nanoscale conformation of adsorbed CPAM at the cellulose/water interface is characterized in situ by specular neutron reflectometry. The effect of CPAM charge density and added NaCl (10-3 M) is described. At constant molecular weight, the thickness of the CPAM layer adsorbed on cellulose increases with polymer charge density. Addition of NaCl decreases the thickness of a CPAM layer already adsorbed on cellulose. However the thickness of the adsorption layer on cellulose of a CPAM solution pre-equilibrated in NaCl is much higher, because the re-shrunk polymer coils do not relax as much upon adsorption.Deuterated cellulose film having better contrast for neutron reflectometry is investigated. Incorporation of deuterium into bacterial cellulose is achieved by growing Gluconacetobacter xylinus - strain ATCC 53524 in a mixture of deuterated glucose and deuterated glycerol. Two strategies are compared for synthesizing deuterated cellulose derivatives that are soluble in volatile solvents (acetone and toluene) suitable for spin coating: one involves acetylation in acetic anhydride, the other trimethylsilylation in ionic liquid (1-butyl-3-methylimidazolium chloride). The trimethylsilylation of deuterated cellulose results in a much higher yield of product, and is used to prepare toluene solutions for spin-coating onto smooth flat silicon substrates. The resulting thin film is hydrolysed back to deuterated cellulose using hydrogen chloride vapour.The data generated is used to prepare improved substrate papers for use in PADs with high wet strength, controlled structure and fine-tuned surface properties.