Polymer Reaction & Colloid Engineering
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2 a Primer on Polymer Colloids: Structure, Synthesis and Colloidal Stability
A. Al Shboul, F. Pierre, and J. P. Claverie 2 A primer on polymer colloids: structure, synthesis and colloidal stability 2.1 Introduction A colloid is a dispersion of very fine objects in a fluid [1]. These objects can be solids, liquids or gas, and the corresponding colloidal dispersion is then referred to as sus- pension, emulsion or foam. Colloids possess unique characteristics. For example, as their size is smaller than the wavelength of light, they scatter light. They also offer a large interfacial surface area, meaning that interfacial phenomena are of paramount importance in these dispersions. The weight of each dispersed particle being small, gravity and buoyancy forces are not sufficient to counteract the thermal random mo- tion of the particle, named Brownian motion (in tribute to the 19th century botanist Robert Brown who first characterized it). The particles do not remain in a dispersed state indefinitely: they will sooner or later aggregate (phase separation). Thus, thecol- loidal state is in general metastable and colloidal stability is one of the key features to take into account when working with colloids. Among all colloids, the polymer colloid family is one of the most widely inves- tigated [2]. Polymer colloids are used for a large number of applications, ranging from coatings, adhesives, inks, impact modifiers, drug-delivery vehicles, etc. The particles range in size from about 10 nm to 1 000 nm (1 μm) in diameter. They are usually spherical, but numerous other shapes have been observed. Polymer colloids are not uncommon in nature. For example, natural rubber latex, the secretion of the Hevea brasiliensis tree, is in fact a dispersion of polyisoprene nanoparticles in wa- ter. -
Plasmofluidic Single-Molecule Surface-Enhanced Raman
ARTICLE Received 24 Feb 2014 | Accepted 9 Jun 2014 | Published 7 Jul 2014 DOI: 10.1038/ncomms5357 Plasmofluidic single-molecule surface-enhanced Raman scattering from dynamic assembly of plasmonic nanoparticles Partha Pratim Patra1, Rohit Chikkaraddy1, Ravi P.N. Tripathi1, Arindam Dasgupta1 & G.V. Pavan Kumar1 Single-molecule surface-enhanced Raman scattering (SM-SERS) is one of the vital applications of plasmonic nanoparticles. The SM-SERS sensitivity critically depends on plasmonic hot-spots created at the vicinity of such nanoparticles. In conventional fluid-phase SM-SERS experiments, plasmonic hot-spots are facilitated by chemical aggregation of nanoparticles. Such aggregation is usually irreversible, and hence, nanoparticles cannot be re-dispersed in the fluid for further use. Here, we show how to combine SM-SERS with plasmon polariton-assisted, reversible assembly of plasmonic nanoparticles at an unstructured metal–fluid interface. One of the unique features of our method is that we use a single evanescent-wave optical excitation for nanoparticle assembly, manipulation and SM-SERS measurements. Furthermore, by utilizing dual excitation of plasmons at metal–fluid interface, we create interacting assemblies of metal nanoparticles, which may be further harnessed in dynamic lithography of dispersed nanostructures. Our work will have implications in realizing optically addressable, plasmofluidic, single-molecule detection platforms. 1 Photonics and Optical Nanoscopy Laboratory, h-cross, Indian Institute of Science Education and Research, Pune 411008, India. Correspondence and requests for materials should be addressed to G.V.P.K. (email: [email protected]). NATURE COMMUNICATIONS | 5:4357 | DOI: 10.1038/ncomms5357 | www.nature.com/naturecommunications 1 & 2014 Macmillan Publishers Limited. All rights reserved. -
Entropy Driven Phase Transition in Polymer Gels: Mean Field Theory
entropy Article Entropy Driven Phase Transition in Polymer Gels: Mean Field Theory Miron Kaufman Physics Department, Cleveland State University, Cleveland, OH 44115, USA; [email protected] Received: 16 April 2018; Accepted: 27 June 2018; Published: 30 June 2018 Abstract: We present a mean field model of a gel consisting of P polymers, each of length L and Nz polyfunctional monomers. Each polyfunctional monomer forms z covalent bonds with the 2P bifunctional monomers at the ends of the linear polymers. We find that the entropy dependence on the number of polyfunctional monomers exhibits an abrupt change at Nz = 2P/z due to the saturation of possible crosslinks. This non-analytical dependence of entropy on the number of polyfunctionals generates a first-order phase transition between two gel phases: one poor and the other rich in poly-functional molecules. Keywords: crosslinking entropy; saturation; discontinuous phase transition 1. Motivation A polymer gel like polyacrylamide changes the volumes by a large factor of ~1000 when a small quantity of solvent like acetone is added to the solution or when the temperature is varied slightly. Central to the understanding of this phase transition are the covalent crosslinks [1–5] between the linear chains. Polymer chains, such as in hydroxypropylcellulose (HPC) immersed in a water solution, form hydrogen bonds with the water. As the temperature, the pH, or some other external condition is varied, there is a change in the strength of the hydrogen bonds that results in the formation or destruction of aggregates of crosslinked polymer chains. Light scattering experiments [6,7] are used to study the influence of the amount of crosslinkers on the properties of the gel phases. -
Generation and Stability of Size-Adjustable Bulk Nanobubbles
www.nature.com/scientificreports OPEN Generation and Stability of Size-Adjustable Bulk Nanobubbles Based on Periodic Pressure Received: 10 September 2018 Accepted: 18 December 2018 Change Published: xx xx xxxx Qiaozhi Wang, Hui Zhao, Na Qi, Yan Qin, Xuejie Zhang & Ying Li Recently, bulk nanobubbles have attracted intensive attention due to the unique physicochemical properties and important potential applications in various felds. In this study, periodic pressure change was introduced to generate bulk nanobubbles. N2 nanobubbles with bimodal distribution and excellent stabilization were fabricated in nitrogen-saturated water solution. O2 and CO2 nanobubbles have also been created using this method and both have good stability. The infuence of the action time of periodic pressure change on the generated N2 nanobubbles size was studied. It was interestingly found that, the size of the formed nanobubbles decreases with the increase of action time under constant frequency, which could be explained by the diference in the shrinkage and growth rate under diferent pressure conditions, thereby size-adjustable nanobubbles can be formed by regulating operating time. This study might provide valuable methodology for further investigations about properties and performances of bulk nanobubbles. Nanobubbles are gaseous domains which could be found at the solid/liquid interface or in solution, known as surface nanobubbles (SNBs)1,2 and bulk nanobubbles (BNBs)3, respectively. For BNBs, generally recognized as spherical bubbles with the diameter of less than 1μm surrounded by liquid, though it has been observed frstly in 19814, the existence of long-lived BNBs is still a controversial subject as it is contrary to the classical theory5,6. -
Soft Condensed Matter Physics Programme Course 6 Credits Mjuka Material TFYA37 Valid From: 2018 Spring Semester
1(9) Soft Condensed Matter Physics Programme course 6 credits Mjuka material TFYA37 Valid from: 2018 Spring semester Determined by Board of Studies for Electrical Engineering, Physics and Mathematics Date determined LINKÖPING UNIVERSITY FACULTY OF SCIENCE AND ENGINEERING LINKÖPING UNIVERSITY SOFT CONDENSED MATTER PHYSICS FACULTY OF SCIENCE AND ENGINEERING 2(9) Main field of study Applied Physics, Physics Course level Second cycle Advancement level A1X Course offered for Biomedical Engineering, M Sc in Engineering Engineering Biology, M Sc in Engineering Entry requirements Note: Admission requirements for non-programme students usually also include admission requirements for the programme and threshold requirements for progression within the programme, or corresponding. Prerequisites Mandatory courses in mathematics and physics for the Y-program or equal. Intended learning outcomes The course will ive the student knowledge of the statistical physics of polymers, the chemical, geometrical and electronic structure of polymers as well as the structure, dynamics and processing of polymer solids. We will discuss condensed matter in the form of colloids, amphiphiles, liquid crystals, molecular crystals and biological matter. After the course, the student should be able to describe the geometry of polymer chains and their dynamics, and the mathematical description of these phenomena utilize thermodynamical analysis of phase transitions in polymers and polymer blends LINKÖPING UNIVERSITY SOFT CONDENSED MATTER PHYSICS FACULTY OF SCIENCE AND ENGINEERING 3(9) describe micro and nanostructure of polymer solutions and polymer blends describe amphiphile materials, colloids, foams and gels, liquid crystals Course content Polymers: terminology, chemical structures and polymerization, solid state structures, polymers in solution, colligative properties. Statistical physics of polymer chains: random coils, entropy measures, rubber physics. -
Shape Memory and Actuation Behavior of Semicrystalline Polymer Networks
Dipl.-Phys. Martin Bothe Shape Memory and Actuation Behavior of Semicrystalline Polymer Networks BAM-Dissertationsreihe • Band 121 Berlin 2014 Die vorliegende Arbeit entstand an der BAM Bundesanstalt für Materialforschung und -prüfung. Impressum Shape Memory and Actuation Behavior of Semicrystalline Polymer Networks 2014 Herausgeber: BAM Bundesanstalt für Materialforschung und -prüfung Unter den Eichen 87 12205 Berlin Telefon: +49 30 8104-0 Telefax: +49 30 8112029 E-Mail: [email protected] Internet: www.bam.de Copyright © 2014 by BAM Bundesanstalt für Materialforschung und -prüfung Layout: BAM-Referat Z.8 ISSN 1613-4249 ISBN 978-3-9816668-1-6 Shape Memory and Actuation Behavior of Semicrystalline Polymer Networks vorgelegt von Dipl.-Phys. Martin Bothe aus Tubingen¨ von der Fakult¨at II – Mathematik und Naturwissenschaften der Technischen Universit¨at Berlin zur Erlangung des akademischen Grades Doktor der Naturwissenschaften – Dr. rer. nat. – genehmigte Dissertation Promotionsausschuss: Vorsitzender: Prof. Dr.-Ing. Matthias Bickermann Gutachter: Prof. Dr. rer. nat. Michael Gradzielski Gutachter: Prof. Dr. rer. nat. Michael Maskos Tag der wissenschaftlichen Aussprache: 16.07.2014 Berlin 2014 D 83 Für meine Familie Abstract Shape memory polymers (SMPs) can change their shape on application of a suitable stimulus. To enable such behavior, a ‘programming’ procedure fixes a deformation, yielding a stable tem- porary shape. In thermoresponsive SMPs, subsequent heating triggers entropy-elastic recovery of the initial shape. An additional shape change on cooling, i.e. thermoreversible two-way actuation, can be stimulated by a crystallization phenomenon. In this thesis, cyclic thermomechanical measurements systematically determined (1) the shape memory and (2) the actuation behavior under constant load as well as under stress-free condi- tions. -
Polymer Exemption Guidance Manual POLYMER EXEMPTION GUIDANCE MANUAL
United States Office of Pollution EPA 744-B-97-001 Environmental Protection Prevention and Toxics June 1997 Agency (7406) Polymer Exemption Guidance Manual POLYMER EXEMPTION GUIDANCE MANUAL 5/22/97 A technical manual to accompany, but not supersede the "Premanufacture Notification Exemptions; Revisions of Exemptions for Polymers; Final Rule" found at 40 CFR Part 723, (60) FR 16316-16336, published Wednesday, March 29, 1995 Environmental Protection Agency Office of Pollution Prevention and Toxics 401 M St., SW., Washington, DC 20460-0001 Copies of this document are available through the TSCA Assistance Information Service at (202) 554-1404 or by faxing requests to (202) 554-5603. TABLE OF CONTENTS LIST OF EQUATIONS............................ ii LIST OF FIGURES............................. ii LIST OF TABLES ............................. ii 1. INTRODUCTION ............................ 1 2. HISTORY............................... 2 3. DEFINITIONS............................. 3 4. ELIGIBILITY REQUIREMENTS ...................... 4 4.1. MEETING THE DEFINITION OF A POLYMER AT 40 CFR §723.250(b)... 5 4.2. SUBSTANCES EXCLUDED FROM THE EXEMPTION AT 40 CFR §723.250(d) . 7 4.2.1. EXCLUSIONS FOR CATIONIC AND POTENTIALLY CATIONIC POLYMERS ....................... 8 4.2.1.1. CATIONIC POLYMERS NOT EXCLUDED FROM EXEMPTION 8 4.2.2. EXCLUSIONS FOR ELEMENTAL CRITERIA........... 9 4.2.3. EXCLUSIONS FOR DEGRADABLE OR UNSTABLE POLYMERS .... 9 4.2.4. EXCLUSIONS BY REACTANTS................ 9 4.2.5. EXCLUSIONS FOR WATER-ABSORBING POLYMERS........ 10 4.3. CATEGORIES WHICH ARE NO LONGER EXCLUDED FROM EXEMPTION .... 10 4.4. MEETING EXEMPTION CRITERIA AT 40 CFR §723.250(e) ....... 10 4.4.1. THE (e)(1) EXEMPTION CRITERIA............. 10 4.4.1.1. LOW-CONCERN FUNCTIONAL GROUPS AND THE (e)(1) EXEMPTION................. -
Review Article Importance of Molecular Interactions in Colloidal Dispersions
Hindawi Publishing Corporation Advances in Condensed Matter Physics Volume 2015, Article ID 683716, 8 pages http://dx.doi.org/10.1155/2015/683716 Review Article Importance of Molecular Interactions in Colloidal Dispersions R. López-Esparza,1,2 M. A. Balderas Altamirano,1 E. Pérez,1 and A. Gama Goicochea1,3 1 Instituto de F´ısica, Universidad Autonoma´ de San Luis Potos´ı, 78290 San Luis Potos´ı, SLP, Mexico 2Departamento de F´ısica, Universidad de Sonora, 83000 Hermosillo, SON, Mexico 3Innovacion´ y Desarrollo en Materiales Avanzados A. C., Grupo Polynnova, 78211 San Luis Potos´ı, SLP, Mexico Correspondence should be addressed to A. Gama Goicochea; [email protected] Received 21 May 2015; Accepted 2 August 2015 Academic Editor: Jan A. Jung Copyright © 2015 R. Lopez-Esparza´ et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We review briefly the concept of colloidal dispersions, their general properties, and some of their most important applications, as well as the basic molecular interactions that give rise to their properties in equilibrium. Similarly, we revisit Brownian motion and hydrodynamic interactions associated with the concept of viscosity of colloidal dispersion. It is argued that the use of modern research tools, such as computer simulations, allows one to predict accurately some macroscopically measurable properties by solving relatively simple models of molecular interactions for a large number of particles. Lastly, as a case study, we report the prediction of rheological properties of polymer brushes using state-of-the-art, coarse-grained computer simulations, which are in excellent agreement with experiments. -
As a Solid Polymer Electrolyte for Lithium Ion Batteries
UPTEC K 16013 Examensarbete 30 hp Juli 2016 A study of poly(vinyl alcohol) as a solid polymer electrolyte for lithium ion batteries Gustav Ek Abstract A study of poly(vinyl alcohol) as a solid polymer electrolyte for lithium ion batteries Gustav Ek Teknisk- naturvetenskaplig fakultet UTH-enheten The use of solid polymer electrolytes in lithium-ion batteries has the advantage in terms of safety and processability, however they often lack in terms of performance. Besöksadress: This is of major concern in applications where high current densities or rapidly Ångströmlaboratoriet Lägerhyddsvägen 1 changing currents are important. Such applications include electrical vehicles and Hus 4, Plan 0 energy storage of the electrical grid to accommodate fluctuations when using renewable energy sources such as wind and solar. Postadress: Box 536 751 21 Uppsala In this study, the use of commercial poly(vinyl alcohol) (PVA) as a solid polymer electrolyte for use in lithium-ion batteries has been evaluated. Films were prepared Telefon: using various lithium salts such as lithium bis(trifluoromethane)sulfonimide (LiTFSI) 018 – 471 30 03 and casting techniques. Solvent free films were produced by substituting the solvent Telefax: Dimethyl sulfoxide (DMSO) with water and rigouros drying or by employing a 018 – 471 30 00 hot-pressing technique. The best performing system studied was PVA-LiTFSI-DMSO, which reached ionic conductivities of 4.5E-5 S/cm at room temperature and 0.45 Hemsida: mS/cm at 60 °C. The solvent free films showed a drop of ionic conductivity by http://www.teknat.uu.se/student roughly one order of magnitude compared to films with residual DMSO present. -
Colloidal Crystal: Emergence of Long Range Order from Colloidal Fluid
Colloidal Crystal: emergence of long range order from colloidal fluid Lanfang Li December 19, 2008 Abstract Although emergence, or spontaneous symmetry breaking, has been a topic of discussion in physics for decades, they have not entered the set of terminologies for materials scientists, although many phenomena in materials science are of the nature of emergence, especially soft materials. In a typical soft material, colloidal suspension system, a long range order can emerge due to the interaction of a large number of particles. This essay will first introduce interparticle interactions in colloidal systems, and then proceed to discuss the emergence of order, colloidal crystals, and finally provide an example of applications of colloidal crystals in light of conventional molecular crystals. 1 1 Background and Introduction Although emergence, or spontaneous symmetry breaking, and the resultant collective behav- ior of the systems constituents, have manifested in many systems, such as superconductivity, superfluidity, ferromagnetism, etc, and are well accepted, maybe even trivial crystallinity. All of these phenonema, though they may look very different, share the same fundamental signature: that the property of the system can not be predicted from the microscopic rules but are, \in a real sense, independent of them. [1] Besides these emergent phenonema in hard condensed matter physics, in which the interaction is at atomic level, interactions at mesoscale, soft will also lead to emergent phenemena. Colloidal systems is such a mesoscale and soft system. This size scale is especially interesting: it is close to biogical system so it is extremely informative for understanding life related phenomena, where emergence is origin of life itself; it is within visible light wavelength, so that it provides a model system for atomic system with similar physics but probable by optical microscope. -
Universality in Spectral Condensation Induja Pavithran1, Vishnu R
www.nature.com/scientificreports OPEN Universality in spectral condensation Induja Pavithran1, Vishnu R. Unni2*, Alan J. Varghese3, D. Premraj3, R. I. Sujith3,4*, C. Vijayan1, Abhishek Saha2, Norbert Marwan4 & Jürgen Kurths4,5,6 Self-organization is the spontaneous formation of spatial, temporal, or spatiotemporal patterns in complex systems far from equilibrium. During such self-organization, energy distributed in a broadband of frequencies gets condensed into a dominant mode, analogous to a condensation phenomenon. We call this phenomenon spectral condensation and study its occurrence in fuid mechanical, optical and electronic systems. We defne a set of spectral measures to quantify this condensation spanning several dynamical systems. Further, we uncover an inverse power law behaviour of spectral measures with the power corresponding to the dominant peak in the power spectrum in all the aforementioned systems. During self-organization, an ordered pattern emerges from an initially disordered state. In dynamical systems, a pattern can be any regularly repeating arrangements in space, time or both1. For example, a laser emits random wave tracks like a lamp until the critical pump power, above which the laser emits light as a single coherent wave track with high-intensity2. A macroscopic change is observed in the laser system as a long-range pattern emerges in time. Another example is the Rayleigh–Bénard system. For lower temperature gradients, the fuid parcels move randomly. As the temperature gradient is increased, a rolling motion sets in and the fuid parcels behave coherently to form spatially extended patterns. Te initial random pattern can be regarded as a superposition of a variety of oscillatory modes and eventually some oscillatory modes dominate, resulting in the emergence of a spatio-temporal pattern3,4. -
Surface Plasmon Resonance Study of the Purple Gold
SURFACE PLASMON RESONANCE STUDY OF THE PURPLE GOLD (AuAl2) INTERMETALLIC, pH-RESPONSIVE FLUORESCENCE GOLD NANOPARTICLES, AND GOLD NANOSPHERE ASSEMBLY Panupon Samaimongkol Dissertation submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy In Physics Hans D. Robinson, Chair Giti Khodaparast Chenggang Tao Webster Santos June 22, 2018 Blacksburg, Virginia Keywords: Surface plasmons (SPs), Localized surface plasmon resonances (LSPRs), Kretschmann configuration, Surface plasmon-enhanced fluorescence (PEF) spectroscopy, Self-Assembly, Nanoparticles Copyright 2018, Panupon Samaimongkol i SURFACE PLASMON RESONANCE STUDY OF THE PURPLE GOLD (AuAl2) INTERMETALLIC, pH-RESPONSIVE FLUORESCENCE GOLD NANOPARTICLES, AND GOLD NANOSPHERE ASSEMBLY Panupon Samaimongkol ABSTRACT (academic) In this dissertation, I have verified that the striking purple color of the intermetallic compound AuAl2, also known as purple gold, originates from surface plasmons (SPs). This contrasts to a previous assumption that this color is due to an interband absorption transition. The existence of SPs was demonstrated by launching them in thin AuAl2 films in the Kretschmann configuration, which enables us to measure the SP dispersion relation. I observed that the SP energy in thin films of purple gold is around 2.1 eV, comparable to previous work on the dielectric function of this material. Furthermore, SP sensing using AuAl2 also shows the ability to measure the change in the refractive index of standard sucrose solution. AuAl2 in nanoparticle form is also discussed in terms of plasmonic applications, where Mie scattering theory predicts that the particle bears nearly uniform absorption over the entire visible spectrum with an order magnitude higher absorption than efficient light-absorbing carbonaceous particle also known a carbon black.