[PDF] Brush Coated Nanoparticle Polymer Thin Films eBook

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Page : pages
File Size : 10,13 MB
Release : 2015
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Executive Summary Our work was devoted to understanding the structure and properties of a class of thin film polymer nanocomposites (PNCs). PNCs are composed of polymer hosts into which nanoparticles (metallic nanoparticles, quantum dots, nanorods, C60, nanotubes) are incorporated. PNCs exhibit a diverse range of functional properties (optical, electronic, mechanical, biomedical, structural), determined in part by the chemical composition of the polymer host and the type of nanoparticle. The properties PNCs rely not only on specific functional, size-dependent, behavior of the nanoparticles, but also on the dispersion, and organizational order in some cases, inter-nanoparticle separation distances, and on relative interactions between the nanoparticles and the host. Therefore the scientific challenges associated with understanding the interrelations between the structure and function/properties of PNCs are far more complex than may be understood based only on the knowledge of the compositions of the constituents. The challenges of understanding the structure-function behavior of PNCs are further compounded by the fact that control of the dispersion of the nanoparticles within the polymer hosts is difficult; one must learn how to disperse inorganic particles within an organic host. The goal of this proposal was to develop an understanding of the connection between the structure and the thermal (glass transition), mechanical and optical properties of a specific class of PNCs. Specifically PNCs composed of polymer chain grafted gold nanoparticles within polymer hosts. A major objective was to understand how to develop basic principles that enable the fabrication of functional materials possessing optimized morphologies and combinations of materials properties. Accomplishments: We developed: (1) fundamental principles that enabled the creation of thin film PNCs possessing more complex morphologies of homopolymers and block copolymer micellar systems [1-6]; (2) a new understanding of physical phenomena associated with the structure of PNC systems and the glass transition and dynamics [7-11], including surface dynamics [12, 13]; designed PNCs to understand the connection between structure and specific optical responses of the material [14, 15]; electrorheological phenomena [16-18]; coarsening/aggregation phenomena [19, 20]; directed assembly [21] and elastic mechanical properties of thin supported films [22]. We established procedures to design and control the spatial distribution of gold nanoparticles (Au-NP), onto which polystyrene (PS) chains were end-grafted, within thin film PS hosts.[1-3] We explained how enthalpic and entropic interactions between the grafted layers and the polymer host chains, the nanoparticle (NP) sizes and shapes determine the spatial distribution of NPs within the host (i.e.: the morphology). In brief, the chemistries of the grafted chains and the polymer hosts, the degrees of polymerization of grafted and host chains (N and P, respectively), and the surface grafting densities [Sigma] influence the thermodynamic interactions. Thin films are unique: the external interfaces (substrate and free surface) profoundly influence the spatial distribution of NPs within the PNC. For example, thin films are thermodynamically less stable than their bulk analogs due to the preferential attraction between the brush-coated nanoparticles and the external interfaces (i.e.: the free surface/polymer interface and the polymer/substrate interface). We investigated the organization of the brush-coated nanoparticles within a host composed on block copolymer micelles in a homopolymer [4, 5]. Block copolymers, composed of a polymer of type A that is bonded covalently to another polymer of type B (A-b-B) are known to form micelles within homopolymers A or B.A micelle is composed of an inner core of the A component of the copolymer and an outer corona of the B-component, that resides within homopolymer B, which serves as the host. If t ...

Author : Rigoberto C. Advincula
Publisher : John Wiley & Sons
Page : 501 pages
File Size : 48,70 MB
Release : 2006-03-06
Category : Technology & Engineering
ISBN : 3527604995

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Materials scientists, polymer chemists, surface physicists and materials engineers will find this book a complete and detailed treatise on the field of polymer brushes, their synthesis, characterization and manifold applications. In a first section, the various synthetic pathways and different surface materials are introduced and explained, followed by a second section covering important aspects of characterization and analysis in both flat surfaces and particles. These specific surface initiated polymerization (SIP) systems such as linear polymers, homopolymers, block copolymers, and hyperbranched polymers are unique compared to previously reported systems by chemisorption or physisorption. They have found their way in both large-scale and miniature applications of polymer brushes, which is covered in the last section. Such 'hairy' surfaces offer fascinating opportunities for addressing numerous problems of both academic and, in particular, industrial interest: high-quality, functional or protective coatings, composite materials, surface engineered particles, metal-organic interfaces, biological applications, micro-patterning, colloids, nanoparticles, functional devices, and many more. It is the desire of the authors that this book will be of benefit to readers who want to "brush-up on polymers".

Author : Wolfgang Knoll
Publisher : John Wiley & Sons
Page : 1107 pages
File Size : 50,9 MB
Release : 2013-02-12
Category : Science
ISBN : 3527638490

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Very thin film materials have emerged as a highly interesting and useful quasi 2D-state functionality. They have given rise to numerous applications ranging from protective and smart coatings to electronics, sensors and display technology as well as serving biological, analytical and medical purposes. The tailoring of polymer film properties and functions has become a major research field. As opposed to the traditional treatise on polymer and resin-based coatings, this one-stop reference is the first to give readers a comprehensive view of the latest macromolecular and supramolecular film-based nanotechnology. Bringing together all the important facets and state-of-the-art research, the two well-structured volumes cover film assembly and depostion, functionality and patterning, and analysis and characterization. The result is an in-depth understanding of the phenomena, ordering, scale effects, fabrication, and analysis of polymer ultrathin films. This book will be a valuable addition for Materials Scientists, Polymer Chemists, Surface Scientists, Bioengineers, Coatings Specialists, Chemical Engineers, and Scientists working in this important research field and industry.

Author : Sabu Thomas
Publisher : Elsevier
Page : 690 pages
File Size : 20,86 MB
Release : 2023-05-10
Category : Technology & Engineering
ISBN : 0323907792

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Polymer-Based Nanoscale Materials for Surface Coatings presents the latest advances and emerging technologies in polymer-based nanomaterials for coatings, focusing on novel materials, characterization techniques, and cutting-edge applications. Sections present the fundamentals of surface preparation and nanocoatings, linking materials and properties, explaining the correlation between morphology, surface phenomena, and surface protection mechanism, and covering theory, modeling and simulation. Other presented topics cover characterization methods, with an emphasis on the latest developments in techniques and approaches. Aging and lifecycle assessment of coated surfaces and coatings are also discussed.Final sections explore advanced applications across a range of fields, including intelligent coatings for biomedical implants, self-healing coatings, syper-hydrophobicity, electroluminescence, sustainable edible coatings, marine antifouling, corrosion resistance, and photocatalytic coatings. Explains the fundamentals of coatings and surface protection, mechanisms, materials and properties, and modeling and simulation Presents detailed information on the latest characterization techniques to prepare nanoscale polymer coatings with enhanced properties Explores a broad range of state-of-the-art applications and considers aging and lifecycle assessments of coatings

Author : Omar Azzaroni
Publisher : John Wiley & Sons
Page : 840 pages
File Size : 40,77 MB
Release : 2018-01-11
Category : Technology & Engineering
ISBN : 1119455014

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Serves as a guide for seasoned researchers and students alike, who wish to learn about the cross-fertilization between biology and materials that is driving this emerging area of science This book covers the most relevant topics in basic research and those having potential technological applications for the field of biopolymer brushes. This area has experienced remarkable increase in development of practical applications in nanotechnology and biotechnology over the past decade. In view of the rapidly growing activity and interest in the field, this book covers the introductory features of polymer brushes and presents a unifying and stimulating overview of the theoretical aspects and emerging applications. It immerses readers in the historical perspective and the frontiers of research where our knowledge is increasing steadily—providing them with a feeling of the enormous potential, the multiple applications, and the many up-and-coming trends behind the development of macromolecular interfaces based on the use of polymer brushes. Polymer and Biopolymer Brushes: Fundamentals and Applications in Materials offers chapters on: Functionalization of Surfaces Using Polymer Brushes; Polymer Brushes by ATRP and Surface-Mediated RAFT Polymerization for Biological Functions; Electro-Induced Copper Catalyzed Surface Modification with Monolayer and Polymer Brush; Polymer Brushes on Flat and Curved Substrates; Biomimetic Anchors for Antifouling Polymer Brush Coating; Glycopolymer Brushes Presenting Sugars in Their Natural Form; Smart Surfaces Modified with Phenylboronic Acid-Containing Polymer Brushes; DNA Brushes; Polymer Brushes as Interfacial Materials for Soft Metal Conductors and Electronics; and more. Presents a comprehensive theory/simulation section that will be valuable for all readers Includes chapters not only on the biological applications of polymer brushes but also on biological systems that resemble polymer brushes on flat surfaces Addresses applications in coatings, friction, sensors, microelectromechanical systems, and biomaterials Devotes particular attention to the functional aspects of hybrid nanomaterials employing polymer brushes as functional units Polymer and Biopolymer Brushes: Fundamentals and Applications in Materials is aimed at both graduate students and researchers new to this subject as well as scientists already engaged in the study and development of polymer brushes.

Author : Abhinav Rastogi
Publisher :
Page : 0 pages
File Size : 25,79 MB
Release : 2009
Category :
ISBN :

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The ability to pattern functional polymers at different length scales is important for the advancement of modern science and technology. This dissertation mainly describes the work done on the high resolution patterning of polymer thin films that have a variety of potential uses. The nanoscale patterning of spun-coated polar polymers was demonstrated using environmentally benign supercritical carbon dioxide (scCO2) as a processing solvent. The use of scCO2 as a processing solvent has several technical advantages that help resolve some of the key problems faced in lithography. In addition, it helps reduce the energy and resource usage that can negatively affect the environment. scCO2 is generally a poor solvent for high molecular weight polymers that are used as standard photoresists. Chapter 2 describes a series of fluorinated quaternary ammonium salts that were synthesized and used as CO2 compatible additives to aid the dissolution of polar polymer photoresists in scCO2. Using these dissolution aids, patterns as small as 100 nm lines were obtained with scCO2 development. Chapters 3 and 4 focus on the patterning of high-tech thin polymer films referred to as polymer brushes. In these films the polymer chains are covalently attached to a surface. A direct method of patterning polymer brushes in a single step using electron beam lithography has been described. Polymer brushes of different structures such as poly(methyl methacrylate) (PMMA) brushes , poly(2-hydroxyethyl methacrylate) (PHEMA) brushes, poly(isobutyl methacrylate) (PIBMA) brushes, poly(neopentyl methacrylate) (PNPMA) brushes and poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) brushes were grown via atom transfer radical polymerization. These brushes were directly patterned using e-beam and their sensitivity to e-beam patterning has been compared and explained. This direct patterning approach produced polymer brush patterns down to 50 nm lines. Due to the number of advantages of using scCO2 as a processing solvent, the dry development of a directly patterned low surface energy coating composed of PTFEMA brushes in scCO2 has been demonstrated in Chapter 4. Using scCO2 as a developer, patterned PTFEMA brushes with 150 nm lines were obtained. Polymer brushes have been used to prepare biocompatible surfaces with reduced non-specific adsorption. Chapter 5 describes the synthesis of a new oligo(ethylene glycol) containing ATRP intiator to prevent non-specific adsorption of biomolecules on polymer brush coated gold electrodes. The adsorption of non-specific antibodies on modified gold electrodes was studied using cyclic voltammetry. Poly(acrylic acid) brushes grown using this new ATRP initiator showed reduced nonspecific binding of the gold electrodes. There has been a continuing need for developing new medical countermeasures for emerging infectious diseases. Chapter 6 describes the role of functionalized poly(acrylic acid) brushes in the development of a biosensor based on sensitive electrochemical detection of the intrinsic catalytic activity of antibodies. Poly(acrylic acid) brushes have been functionalized with 2,4-dinitrophenyl groups (model antigen) and Ni-NTA to immobilize specific antibodies on the sensor surface. The modification of gold surfaces with polymer brushes provides a bio- and electronically compatible substrate with high density of specific haptens with reduced non-specific adsorption.

Author : Abbass A. Hashim
Publisher : BoD – Books on Demand
Page : 340 pages
File Size : 19,71 MB
Release : 2010-04-01
Category : Technology & Engineering
ISBN : 9533070595

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This book provides a timely overview of a current state of knowledge of the use of polymer thin film for important technological applications. Polymer thin film book covers the scientific principles and technologies that are necessary to implement the use of polymer electronic device. A wide-ranging and definitive coverage of this emerging field is provided for both academic and practicing scientists. The book is intended to enable readers with a specific background, e.g. polymer nanotechnology, to become acquainted with other specialist aspects of this multidisciplinary field. Part A of the book covers the fundamental of the key aspect related to the development and improvement of polymer thin film technology and part B covers more advanced aspects of the technology are dealt with nano-polymer layer which provide an up-to-date survey of current research directions in the area of polymer thin film and its application skills.

Author : Materials Research Society. Meeting
Publisher :
Page : 312 pages
File Size : 44,11 MB
Release : 2002
Category : Science
ISBN :

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Polymer interfaces are critical for many technological and industrial applications in thin films including microelectronics, packaging, automotive coatings and sensors. The structure and architecture of interfaces in thin films and bulk polymeric systems can be exceedingly complex. In thin films, the technological drive to diminish film thickness while simultaneously enhancing homogeneity, stability and adhesion, is a demanding challenge driving research in newer areas of nanofilled and controlled nanostructured and nanopatterned materials. Tailoring surface and interfacial properties is equally important for new developments in the traditional fields of bulk polymer blends, adhesion and wetting. There is a need to develop an understanding of interfacial phenomena with the ultimate goal of establishing structure-property relationships with quantitative predictive capabilities and this book discusses these challenges. Topics include: block copolymer films; theory, simulations and dynamics; polymer interfaces and thin films; adhesion and mechanical properties; self-assembly by polymeric films; self-assembly and electronic properties; lithographic, electronic properties; and nanoparticulate-filled films.

Author : Xiaoteng Wang
Publisher :
Page : 172 pages
File Size : 40,73 MB
Release : 2019
Category : Nanoimprint lithography
ISBN :

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Controlled dispersion and distribution of functional nanoparticles (NPs) in polymer matrix is prerequisite for improved properties of the composite materials. How to control the distribution of NPs in a facile manner remains to be a recurring challenge in the applications of polymer nanocomposites (PNCs). Surface functionalization of NPs with polymer brushes has emerged as an effective and versatile platform of tuning the interactions between the nanoparticles and the polymer hosts, allowing their integration into polymer nanocomposites. The current work aims to understand the phase behaviors of polymer-grafted nanoparticles (PGNPs) in polymer thin films and further control the spatial distribution of PGNPs through the interactions between the grafted and matrix polymer chains. In particular, polystyrene-grafted titanium dioxide nanoparticles (PS-TiO2) embedded in polystyrene (PS) thin film matrices having an initial film thickness h0 » 90 nm were investigated, where fluctuations in the grafting brush layer enables the formation of self-assembled PGNP clustering structures. Nanoimprinting directed lateral organization of the PGNP clusters in polymer thin films via topographically soft-pattern confinement was demonstrated. The PGNP clusters segregate to thicker film regions where they are less confined during thermal annealing. The partitioning of the PGNP clusters to the patterned regions was quantified by introducing the cluster partition coefficient Kc. It shows that the highly selective segregation of the clusters was driven by entropic driving forces while the film surface homogenization and shape transition of the clusters were induced by geometrical confinement of the nanopatterning. Simultaneously, the stability of the low molecular weight PS thin films is greatly enhanced against dewetting by the addition of PGNPs. The extent of the dewetting suppression depends on the PGNP concentration and can also be altered by nanopatterning. This form of soft pattern-directed self-assembly may boost colligative properties and provide enhanced and anisotropic optical such as UV-Vis, electronic and other material properties associated with organized NP clusters into precise large-scale patterns. With better understanding of the chemically identical blend systems, we further extend our model study to other PGNP/polymer blends where enthalpic interactions also participate in the phase behavior. The hybrid blend system composed of polystyrene-grafted silica nanoparticles in a poly (vinyl methyl ether) (PS-SiO2/PVME) blend thin film (≈100 nm) was studied where the brush and matrix polymers exhibit LCST type of phase behavior. Phase separation between the polymer-grafted nanoparticles (PGNPs) and matrix polymer occurs at a temperature ≈ 40° C lower than the LCST of classic binary linear PS/PVME polymer blends. Spatially organized PGNP domain structures on submicrometer scale were illustrated by introducing the symmetry-breaking soft elastomer pattern. Selective partition of the nanoparticles in both one-phase and two-phase regions can be obtained via nanoimprinting. Thermal cycling of the composite film through the critical temperature allows for thermodynamically reversible formation and dissolution of PGNP-rich domain structures. This nanoimprinting guided assembly of PGNPs in polymer nanocomposites would open pathways of novel hybrid materials for many technological applications such as responsive materials.