Download or read book The Effects of Polydispersity on the Self assembly of Diblock Copolymers written by Chris Howell and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Polydispersity Ob Block Copolymer Self assembly written by Nathaniel Alexander Lynd and published by . This book was released on 2007 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Polydispersity on the Morphology of Polystyrene polyferrocenyldimethylsilane Block Copolymer Thin Films written by Joy Clare Perkinson and published by . This book was released on 2009 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction: As the size of electronic and magnetic devices decreases, nanoscale patterning becomes an increasingly important area of research. Two different approaches have been taken to pattern media: top-down methods such as lithography, and bottom-up methods such as self-assembly. Top-down assembly methods have the advantages of precision and accuracy, but are hard to scale for certain industrial applications due to their low throughput. Self-assembly methods are more easily scalable for applications requiring mass production. Thus, self-assembly has attracted attention and is an area of ongoing research for its potential to create high-throughput, periodic nanoscale patterns. Block copolymers are a class of commonly-studied materials for nanoscale selfassembly. Block copolymers are long molecules that consist of "blocks" of chemically differing polymers attached end-to-end. Under the right conditions, these blocks will phase separate, spontaneously forming periodic microdomains. Diblock copolymers, which have only two blocks, have been found to form a variety of well-ordered morphologies with nanoscale periodicity ...

Download or read book Amphiphilic Block Copolymers written by P. Alexandridis and published by Elsevier. This book was released on 2000-10-18 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is the belief of the editors of this book that the recognition of block copolymers as being amphiphilic molecules and sharing common features with other well-studied amphiphiles will prove beneficial to both the surfactant and the polymer communities. An aim of this book is to bridge the two communities and cross-fertilise the different fields. To this end, leading researchers in the field of amphiphilic block copolymer self-assembly, some having a background in surfactant chemistry, and others with polymer physics roots, have agreed to join forces and contribute to this book.The book consists of four entities. The first part discusses theoretical considerations behind the block copolymer self-assembly in solution and in the melt. The second part provides case studies of self-assembly in different classes of block copolymers (e.g., polyethers, polyelectrolytes) and in different environments (e.g., in water, in non-aqueous solvents, or in the absence of solvents). The third part presents experimental tools, ranging from static (e.g., small angle neutron scattering) to dynamic (e.g., rheology), which can prove valuable in the characterization of block copolymer self-assemblies. The fourth part offers a sampling of current applications of block copolymers in, e.g., formulations, pharmaceutics, and separations, applications which are based on the unique self-assembly properties of block copolymers.

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 Block Copolymers written by Nikos Hadjichristidis and published by John Wiley & Sons. This book was released on 2003-04-28 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers may be classified as either homopolymers, consisting of one single repeating unit, or copolymers, consisting of two or more distinct repeating units. Block copolymers contain long contiguous blocks of two or more repeating units in the same polymer chain. Covering one of the hottest topics in polymer chemistry, Block Copolymers provides a coherent overview of the synthetic routes, physical properties, and applications of block copolymers. This pioneering text provides not only a guideline for developing synthetic strategies for creating block copolymers with defined characteristics, but also a key to the relationship between the physical properties of block copolymers and the structure and dynamics of materials. Covering features of the chemistry and physics of block copolymers that are not found in comparable texts, Block Copolymers illustrates the structure-activity relationship of block copolymers and offers suggestions for the design of specific applications. Divided into five sections-Block Copolymers includes chapters on: * Block Copolymers by Chemical Modification of Precursor Polymers * Nonlinear Block Copolymers * Adsorption of Block Copolymers at Solid-Liquid Interfaces * Theory of Block Copolymer Segregation * Phase Transformation Kinetics * Block Copolymer Morphology * Block Copolymer Dynamics Polymer chemists, physicists, chemical engineers, and materials scientists, as well as graduate students in polymer science, will find Block Copolymers to be an invaluable text.

Download or read book Manipulating Phase Behavior in Block Copolymers Using Polydispersity written by and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of polydispersity, or broad molecular weight distributions, on the phase behavior of block copolymer melts and thin films are systematically explored. Linear AB diblock, ABA triblock, and BAB triblock copolymers are synthesized with continuous polydispersity in the B block (Mw/Mn 8́ơ 1.70́32.0) and relatively monodisperse A blocks (Mw/Mn 8́ơ 1.10́31.3) to understand how the self0́3assembly of polydisperse block copolymers can be altered with chain architecture and block connectivity. Broad dispersity in the M block of poly(styrene0́3b0́3methyl methacrylate) (SM) diblock copolymer melts induces domain dilation and morphological transitions to higher M block volume compositions with respect to predictions for monodisperse SM diblock copolymers. A comparison between poly(styrene0́3b0́31,40́3butadiene0́3b0́3styrene) triblock copolymers (SBS) with mid0́3block (B) polydispersity and poly(methyl methacrylate0́3b0́3styrene0́3b0́3methyl methacrylate) triblock copolymers (MSM) with outer0́3block (M) polydispersity reveals that the location of the polydisperse block and how it is connected to the other blocks is critical. Center block polydispersity in SBS, where one block is constrained at two block junctions, leads to a lamellar phase window shift to higher volume fractions of B, increases in domain periodicity, and the stabilization of a new, disordered bicontinuous morphology. The domain periodicity in the MSM triblocks with outer M block polydispersity is at least twice that predicted for monodisperse MSM triblock copolymers. However, in contrast to the SBS triblocks, the polydisperse MSM triblocks exhibit a lamellar phase window shift to lower M block compositions. The behavior of the SBS and MSM triblock copolymers is clarified in the context of the chain architectures present in the melts resulting from the block polydispersity. Preliminary studies of the thin film behavior of the SM diblock and MSM triblock copolymers revealed that despite the polydispersity of the M block, perpendicular microdomain orientation can be achieved. The MSM triblock copolymer thin films exhibit film thickness0́3dependent morphological behavior arising from a confluence of M outer0́3block polydispersity and the presence of a random brush0́3modified substrate. In summation, this dissertation demonstrates that polydispersity can be used to manipulate the phase behavior of block copolymer melts and thin films and may facilitate access to new materials with potentially useful properties.

Download or read book Miktoarm Star Polymers written by Ashok Kakkar and published by Royal Society of Chemistry. This book was released on 2017-04-13 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: The term ‘miktoarm polymers’ refers to asymmetric branched macromolecules, a relatively new entry to the macromolecular field. Recent advances in their synthesis and intriguing supramolecular chemistry in a desired medium has seen a fast expansion of their applications. The composition of miktoarm polymers can be tailored and even pre-defined to allow a desired combination of functions, meaning polymer chemists can have complete control of the overall architecture of these macromolecules. By carefully selecting the composition, they can create supramolecular structures with intriguing properties, particularly for applications in biology. Miktoarm Star Polymers features chapters from experts actively working in this field, and provides the reader with a unique introduction to the fundamental principles of this exciting macromolecular system. Topics covered include the design, synthesis, characterization, self-assembly and applications of miktoarm polymers. The book is an excellent overview and up to date guide to those working in research in polymer chemistry, materials science, and polymers for medical applications.

Download or read book Theory of Self assembly of Block Copolymers written by Chien-Yueh Huang and published by . This book was released on 1997 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Block Copolymer Nanocomposites written by Galder Kortaberria and published by CRC Press. This book was released on 2016-10-14 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of the synthesis and characterization of nanocomposites based on block copolymers. Because of the self-assembly capability of block copolymers for the generation of nanostructures, besides their ability to nanostructure thermosetting matrices such as epoxy and polyester, binary or ternary nanocomposites can be prepared with different nanofillers such as nanoparticles and carbon nanotubes. The book starts with a review on nanocomposites based on block copolymers and nanoparticles synthesized with the use of surfactants, followed by a review on nanocomposites with metallic nanoparticles with polymer brushes and those with carbon nanotubes. A chapter is devoted to binary systems based on block copolymers and nanoparticles synthesized by sol-gel. A review on nanocomposites based on thermosetting matrices nanostructured with block copolymers (amphiphilic or chemically modified) is also presented for both epoxy and polyester resins. The work on ternary systems based on thermosetting matrices, block copolymers, and nanoparticles is presented next. The book concludes with a discussion on nanocomposites based on epoxy and block copolymers with azobenzene groups for optical purposes.

Download or read book Developments in Block Copolymers 2 written by I. Goodman and published by Springer. This book was released on 1985-10-31 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Self assembly Behavior in Hydrophilic Block Copolymers written by Clara Valverde Serrano and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Block copolymers are receiving increasing attention in the literature. Reports on amphiphilic block copolymers have now established the basis of their self-assembly behavior: aggregate sizes, morphologies and stability can be explained from the absolute and relative block lengths, the nature of the blocks, the architecture and also solvent selectiveness. In water, self-assembly of amphiphilic block copolymers is assumed to be driven by the hydrophobic. The motivation of this thesis is to study the influence on the self-assembly in water of A b B type block copolymers (with A hydrophilic) of the variation of the hydrophilicity of B from non-soluble (hydrophobic) to totally soluble (hydrophilic). Glucose-modified polybutadiene-block-poly(N-isopropylacrylamide) copolymers were prepared and their self-assembly behavior in water studied. The copolymers formed vesicles with an asymmetric membrane with a glycosylated exterior and poly(N-isopropylacrylamide) on the inside. Above the low critical solution temperature (LCST) of poly(N-isopropylacrylamide), the structure collapsed into micelles with a hydrophobic PNIPAM core and glycosylated exterior. This collapse was found to be reversible. As a result, the structures showed a temperature-dependent interaction with L-lectin proteins and were shown to be able to encapsulate organic molecules. Several families of double hydrophilic block copolymers (DHBC) were prepared. The blocks of these copolymers were biopolymers or polymer chimeras used in aqueous two-phase partition systems. Copolymers based on dextran and poly(ethylene glycol) blocks were able to form aggregates in water. Dex6500-b-PEG5500 copolymer spontaneously formed vesicles with PEG as the "less hydrophilic" barrier and dextran as the solubilizing block. The aggregates were found to be insensitive to the polymer's architecture and concentration (in the dilute range) and only mildly sensitive to temperature. Variation of the block length, yielded different morphologies. A longer PEG chain seemed to promote more curved aggregates following the inverse trend usually observed in amphiphilic block copolymers. A shorter dextran promoted vesicular structures as usually observed for the amphiphilic counterparts. The linking function was shown to have an influence of the morphology but not on the self-assembly capability in itself. The vesicles formed by dex6500-b-PEG5500 showed slow kinetics of clustering in the presence of Con A lectin. In addition both dex6500-b-PEG5500 and its crosslinked derivative were able to encapsulate fluorescent dyes. Two additional dextran-based copolymers were synthesized, dextran-b-poly(vinyl alcohol) and dextran-b-poly(vinyl pyrrolidone). The study of their self-assembly allowed to conclude that aqueous two-phase systems (ATPS) is a valid source of inspiration to conceive DHBCs capable of self-assembling. In the second part the principle was extended to polypeptide systems with the synthesis of a poly(N-hydroxyethylglutamine)-block-poly(ethylene glycol) copolymer. The copolymer that had been previously reported to have emulsifying properties was able to form vesicles by direct dissolution of the solid in water. Last, a series of thermoresponsive copolymers were prepared, dextran-b-PNIPAMm. These polymers formed aggregates below the LCST. Their structure could not be unambiguously elucidated but seemed to correspond to vesicles. Above the LCST, the collapse of the PNIPAM chains induced the formation of stable objects of several hundreds of nanometers in radius that evolved with increasing temperature. The cooling of these solution below LCST restored the initial aggregates. This self-assembly of DHBC outside any stimuli of pH, ionic strength, or temperature has only rarely been described in the literature. This work constituted the first formal attempt to frame the phenomenon. Two reasons were accounted for the self-assembly of such systems: incompatibility of the polymer pairs forming the two blocks (enthalpic) and a considerable solubility difference (enthalpic and entropic). The entropic contribution to the positive Gibbs free energy of mixing is believed to arise from the same loss of conformational entropy that is responsible for "the hydrophobic effect" but driven by a competition for water of the two blocks. In that sense this phenomenon should be described as the "hydrophilic effect".

Download or read book Theory of Block Polymer Self Assembly written by Benjamin R. Magruder and published by American Chemical Society. This book was released on 2024-03-13 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: This primer introduces the theory of self-assembly of block polymers, most notably self-consistent field theory (SCFT). Block polymer self-assembly is a fascinating and highly interdisciplinary topic. This primer can be read at several levels, depending on what readers want to get out of it. Readers who want an overview of self-assembly in block polymer and what SCFT says about the process can read Chapters 1-3 and skip to Chapter 7 to see the open questions. If the reader is further interested in the output of SCFT calculations but not how those outputs are generated, they should read Chapter 6 as well. But if the reader wants to learn how to do the SCFT calculations themselves, Chapters 4 and 5 offer an accessible introduction to the theory and numerical methods, providing an excellent entry point into the literature. This primer includes data that the authors have computed using SCFT. All calculations use the open-source software package Polymer Self-Consistent Field (PSCF), developed by David Morse at the University of Minnesota. Take breaks from reading to watch ten “Insider Q&A” videos included throughout, which offer additional insight from experts in the field, such as An-Chang Shi, Chinedum O. Osuji, Frank S. Bates, Christopher M. Bates, Glenn H. Fredrickson, and Lisa Hall. Furthermore, this primer includes multiple features to aid and enhance readers’ learning. “That’s a Wrap” summarizes key concepts at the end of each chapter, while “Read These Next” suggests references that may interest further reading. A pop-up glossary ensures readers have definitions as needed throughout the primer.

Download or read book The Effects of Polydispersity on Diblock Copolymer Melts written by Thomas Mark Beardsley and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Diblock copolymers (DBCs) are fascinating materials which, under the correct conditions, self-assemble into periodically ordered structures with nanometre sized domains. The majority of theoretical and experimental studies of DBCs have concentrated on the monodisperse melt, where all of the polymers are identical. Although these ideal molecules have allowed for detailed understanding of the phase behaviour of the materials by removing the effects of polydispersity, they are costly and time consuming to manufacture. More recently, however, a range of techniques have emerged that allow chemists to synthesise DBCs more cheaply, albeit with higher levels of polydispersity. These methods will be more attractive to industry providing that the novel material properties remain. Self consistent field theory (SCFT) has made good progress in predicting the effects of polydispersity in DBC melts, such as increasing domain size and shifting of order-order phase boundaries - effects which are observed in experiments. However, whereas SCFT predicts that polydispersity shifts the order-disorder transition (ODT) to higher temperatures, recent experiments have found that this is not always the case and we suspect that this failure is due to the lack of fluctuation effects in the theory. In this study, Monte Carlo simulations are used to investigate DBC melts since the technique includes fluctuation effects. A detailed study of the monodisperse system is performed, providing a benchmark to which the results from polydisperse melts are compared. The simulations are also contrasted with SCFT and experiments in order to resolve the disagreement between them.

Download or read book Self assembly of Block Copolymers in Dilute Solution written by Kathleen A. Cogan and published by . This book was released on 1991 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soft Matter Characterization written by Redouane Borsali and published by Springer Science & Business Media. This book was released on 2008-07-28 with total page 1490 pages. Available in PDF, EPUB and Kindle. Book excerpt: This 2-volume set includes extensive discussions of scattering techniques (light, neutron and X-ray) and related fluctuation and grating techniques that are at the forefront of this field. Most of the scattering techniques are Fourier space techniques. Recent advances have seen the development of powerful direct imaging methods such as atomic force microscopy and scanning probe microscopy. In addition, techniques that can be used to manipulate soft matter on the nanometer scale are also in rapid development. These include the scanning probe microscopy technique mentioned above as well as optical and magnetic tweezers.

Download or read book Directed Self assembly of Block Co polymers for Nano manufacturing written by Roel Gronheid and published by Woodhead Publishing. This book was released on 2015-07-17 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: The directed self-assembly (DSA) method of patterning for microelectronics uses polymer phase-separation to generate features of less than 20nm, with the positions of self-assembling materials externally guided into the desired pattern. Directed self-assembly of Block Co-polymers for Nano-manufacturing reviews the design, production, applications and future developments needed to facilitate the widescale adoption of this promising technology. Beginning with a solid overview of the physics and chemistry of block copolymer (BCP) materials, Part 1 covers the synthesis of new materials and new processing methods for DSA. Part 2 then goes on to outline the key modelling and characterization principles of DSA, reviewing templates and patterning using topographical and chemically modified surfaces, line edge roughness and dimensional control, x-ray scattering for characterization, and nanoscale driven assembly. Finally, Part 3 discusses application areas and related issues for DSA in nano-manufacturing, including for basic logic circuit design, the inverse DSA problem, design decomposition and the modelling and analysis of large scale, template self-assembly manufacturing techniques. Authoritative outlining of theoretical principles and modeling techniques to give a thorough introdution to the topic Discusses a broad range of practical applications for directed self-assembly in nano-manufacturing Highlights the importance of this technology to both the present and future of nano-manufacturing by exploring its potential use in a range of fields