Dissertations / Theses: 'Core-Shell Particle'

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Khaleque, Tasnuva. "Modelling and experimental study of toughening mechanisms of core-shell rubber particle- and nanosilica particle-modified epoxy polymers." Thesis, Imperial College London, 2018. http://hdl.handle.net/10044/1/62639.

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Epoxies are high performance thermosetting polymers widely used in many engineering applications as structural adhesives, coatings and matrices of fibre reinforced polymer composites. They possess exceptional mechanical properties, chemical resistance and high temperature properties. However, the highly cross-linked epoxy networks, are brittle, and epoxies need toughening for engineering applications. This work presents the mechanical properties, fracture performance and toughening mechanisms of an anhydride cured epoxy polymer modified by different combinations of preformed core-shell rubber particles (CSR) and hybrid CSR-nanosilica particles. Two types of CSR particles, with nominal diameters of 100 nm and 300 nm, and nanosilica particles with a diameter of 20 nm were used. The Young's modulus of the epoxy decreased with the increasing weight percentage of CSR particles, but increased with the addition of the nanosilica particles. Both the compressive modulus and yield stress decreased with the increasing CSR particle content; however, the addition of nanosilica led to an increase of the compressive modulus, while the yield stress remained unchanged. The glass transition temperature of the unmodified epoxy was 159 °C and this was unchanged by the addition of the CSR particles or the nanosilica particles. The fracture energy increased from 78 J/m2 for the unmodified epoxy to 530 J/m2 with an addition of 9 wt% of the small CSR particles, this was further enhanced by the addition of the nanosilica particles. The hybrid toughening effect observed was additive, and no synergy was observed. A reactive diluent was added to further enhance the fracture toughness of the particle modified epoxies, and a synergistic toughening effect was observed. The toughening mechanisms identified were the cavitation of the CSR particles followed by plastic void growth in the epoxy matrix and shear band yielding of the epoxy induced by both the CSR and the nanosilica particles. The increases in toughness were successfully predicted using an analytical model. The fracture performances of carbon fibre reinforced polymer composites with matrices of the toughened epoxies were investigated. A complete transfer of toughness from the bulk epoxies to the fibre composites was observed. The toughening mechanisms of the modified epoxies were also investigated through non-linear finite element analyses. A two-dimensional plane strain elastic plastic model was developed to study the shear band yielding mechanism of the CSR modified and the hybrid modified epoxies. The model predicted that the CSR particle size has no significant effect on the shear band yielding mechanism and verified the contribution of the nanosilica particles to the shear band yielding of the hybrid epoxy. The toughening mechanism of the nanosilica particles was studied using a two-dimensional axisymmetric unit-cell model of nanosilica-embedded epoxy under triaxial loading, considering an elastic-plastic response for the epoxy and cohesive interaction between the nanosilica and the epoxy matrix. The model predicted that there is significant plastic deformation of the epoxy before it debonds from the nanosilica.

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Hanga, Mariana P. "Controlled particle production by membrane emulsification for mammalian cell culture and release." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/14922.

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Existing commercially available microcarriers are very efficient at encouraging cell attachment and proliferation. However, recovery of the cells is problematic as it requires the use of proteolytic enzymes which are damaging to critical cell adhesion proteins. From this perspective, temperature responsive polymers appear to be a valid option. The current innovative study is to produce and engineer microcarriers in terms of particle size, surface coating and properties, as well as thermo-responsiveness for cell release. All these benefits are based on particle production by membrane emulsification to provide a highly controlled particle size. The polymer of choice is poly N-isopropylacrylamide (pNIPAM) because of the sharpness of its phase transition, biocompatibility and transition temperature close to the physiological value. These characteristics make pNIPAM a very attractive material for Tissue Engineering applications. Cells are cultured on the hydrophobic surface at 37??C and can be readily detached without using proteolytic enzymes from the surface by lowering the temperature to room temperature. The Dispersion Cell (MicroPore Technologies Ltd, UK) was successfully employed for the production of W/O emulsions. The generated monomer droplets were additionally solidified by applying a free radical polymerisation to manufacture solid pNIPAM microspheres. Additionally, calcium alginate particles were also generated and further functionalised with amine terminated pNIPAM to form temperature responsive core-shell particles by simply taking advantage of the electrostatic interactions between the carboxyl groups of the alginate and amino groups of the modified pNIPAM. Controlled particle production was achieved by varying process parameters and changing the recipe formulation (e.g. monomer concentration, surfactant concentration, pore size and inter-pore spacing, injection rate, shear stress applied at the membrane s surface). The manufactured particles were then analysed in terms of particle size and size distribution, chemical composition, surface analysis, shrinkage ratio and thermo-responsiveness and further sterilised and used for cell culture and release experiments. Swiss Albino 3T3 fibroblastic cells (ATCC, USA) were utilised to show proof-of-concept for this technology. Cell attachment and proliferation were assessed and successfully demonstrated qualitatively and quantitatively. pNIPAM solid particles, uncoated and with different protein coatings were shown to allow a limited degree of cell attachment and proliferation compared to a commercially available microcarrier. On a different approach, uncoated core-shell structures demonstrated improved capabilities for cell attachment and proliferation, similar to commercially available microcarriers. Having in mind the potential of temperature responsive polymers and the aim of this innovative study, cell detachment from the generated microcarriers was evaluated and compared to a commercially available temperature responsive surface. Necessary time for detachment was recorded and detached cells were recovered and reseeded onto tissue culture plastic surfaces in order to evaluate the replating and reattachment capabilities of the recovered cells. Successful cell detachment was achieved when using the core-shell structures as cell microcarriers, but the necessary time of detachment was of an order higher than that for the commercial temperature responsive surface.

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Tungchaiwattana, Somjit. "A study of particle structure and film formation mechanism on the mechanical properties of synthetic rubber films." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/a-study-of-particle-structure-and-film-formation-mechanism-on-the-mechanical-properties-of-synthetic-rubber-films(3014e013-bc99-4fbf-8282-5d13ed4251b3).html.

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This thesis investigated a new group of poly(Bd)/poly(Bd-co-MAA) core-shell particles that were ionically crosslinked and cast as nanostructured ionomer films from aqueous dispersions. The new group of poly(Bd)/poly(Bd-co-MAA) core-shell particles were studied for structure-property relationships and morphology. The covalent crosslinking content in the core and the shell were varied at constant ionic crosslinking. Stress-strain data showed control of the nanostructured films. The chain transfer agent used during the preparation of the nanoparticles core-shells was shown to independently tune the mechanical properties of the films.

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Fujiwara, Atsushi. "Controlling Adsorption Properties of Metal-Organic Framework Particles through Synthesis Protocols." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263694.

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Klingler, Andreas [Verfasser], and Ulf [Akademischer Betreuer] Breuer. "Morphology and Fracture of Block Copolymer and Core-Shell Rubber Particle Modified Epoxies and their Carbon Fibre Reinforced Composites / Andreas Klingler ; Betreuer: Ulf Breuer." Kaiserslautern : Technische Universität Kaiserslautern, 2021. http://d-nb.info/1233286382/34.

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Hain, Jessica. "Funktionalisierte Polymerkomposite auf Basis von Poly(3,4-ethylendioxythiophen) und Gold." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1209477679749-98205.

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Poly(3,4-ethylenedioxythiophene), PEDOT, belongs to the group of conducting polymers and is characterized by its high stability, a moderate band gap and its optical transparency in the conductive state. A large disadvantage of conducting polymers, and also PEDOT, is their poor solubility. One way to achieve processible materials is the synthesis of colloidal particles. Thus, this work focuses on the development of conductive particles by preparing composite structures. Polymeric colloids like latex particles and microgels were used as templates for the oxidative polymerization of EDOT. Depending on template structure completely different composite morphologies with variable properties were obtained. It was found that modification with PEDOT did not only cause conductive particles for application as humidity sensor materials, but also candidates for further functionalization with gold nanoparticles (Au-NPs). Due to a multi-stage synthesis route it was possible to achieve polystyrene(core)-PEDOT(shell)-particles decored with Au-NPs. Microgels acting as “micro reactors” for the incorporation of PEDOT and Au-NPs were also used for preparing multifunctional composites for catalytic applications
Poly(3,4-ethylendioxythiophen), PEDOT, gehört zur Gruppe der leitfähigen Polymere und zeichnet sich durch seine hohe Stabilität, eine moderate Bandlücke und seine optische Transparenz im dotierten Zustand aus. Ein Nachteil leitfähiger Polymere, wie auch von PEDOT, ist deren schlechte Löslichkeit. Die Synthese kolloidaler Partikel bietet jedoch eine Möglichkeit dieses Problem zu umgehen. In diesem Zusammenhang richtete sich der Fokus dieser Arbeit auf die Darstellung leitfähiger Partikel in Form von Kompositstrukturen. Polymerkolloide, wie Latex- und Mikrogelpartikel, sind als Template eingesetzt worden, in deren Gegenwart PEDOT durch eine oxidative Polymerisation synthetisiert wurde. In Abhängigkeit von der Struktur des Templats sind unterschiedliche Kompositmorphologien mit steuerbaren Eigenschaften erhalten worden. Auf diese Weise wurden neben Materialien für die Feuchtigkeitssensorik leitfähige Kompositpartikel hergestellt, die zusätzlich mit Gold-Nanopartikeln (Au-NP) funktionalisiert werden konnten. Durch ein mehrstufiges Syntheseverfahren sind somit Polystyrol(Kern)-PEDOT(Schale)-Partikel mit Au-NP-funktionalisierter Oberfläche synthetisiert worden. Mikrogelpartikel, die als „Mikroreaktoren“ für die Inkorporation von PEDOT- und Au-NP dienten, wurden ebenfalls eingesetzt, um multifunktionale Komposite mit katalytischen Eigenschaften herzustellen

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Sarma, Dominik Arun. "Modular Hybrid Architectures for Single Particle-based Analytical Assays." Doctoral thesis, Humboldt-Universität zu Berlin, 2020. http://dx.doi.org/10.18452/22055.

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Globale Megatrends erfordern immer flexiblere analytische Messmethoden und Assays. Insbesondere im Umwelt-, Agrar-, Lebensmittel- und Gesundheitssektor sind chemische Assays hier eine geeignete Wahl. Eine Vielzahl solcher Assays steht in akademischen und industriellen Bereichen zur Verfügung. Die Anpassung an neue Verbindungen hingegen ist oft schwierig zu realisieren, da der einzelne Test meist für einen spezifischen Analyten konzipiert ist. Eine modulare, analytische Plattform für die Entwicklung chemischer Assays ist daher sehr wünschenswert. Ein solches System sollte die Möglichkeit einer schnellen und flexiblen Implementierung verschiedener Erkennungstypen für neue Analyten und die Möglichkeit einer Multiparameter-(Multiplex-)Bestimmung in einem robusten und portablen Auslesegerät beinhalten. Einzelpartikel-basierte, chemische Assays haben sich hier als geeignete Lösung erwiesen. In dieser Arbeit stelle ich Polystyrol-Kern-Silikat-Schale-Partikel als modulare, hybride Plattform für die flexible Konfiguration von Einzelpartikel-basierten chemischen Assays vor. Zunächst wurde ein Verfahren entwickelt, das den Zugang zu verschiedenen-Partikelarchitekturen ermöglicht. Diese Partikel wurden für den DNA-Nachweis bis in den fmol-Bereich getestet (Kapitel 2). Ein neues Werkzeug zur Bestimmung der Rauheit der Partikel aus elektronenmikroskopischen Bildern wurde entwickelt und auf das breite Spektrum der im Projekt hergestellten SiO2@PS-Partikel angewendet (Kapitel 3). Damit soll die Grundlage zur Vergleichbarkeit zwischen zukünftigen Partikelcharakterisierungen geschaffen werden. Schließlich wurde ein Multiplex-Assay mit farbstoffkodierten, Protein-abweisenden Partikeln entwickelt, um kleine Moleküle durch immunochemische Reaktionen in einem waschfreien Verfahren nachzuweisen (Kapitel 4). Letzteres verdeutlicht, dass eine hohe analytische Leistung mit neuem Potenzial an flexibler Funktionalität durch die Verwendung hybrider SiO2@PS-Partikel kombiniert werden kann.
Global megatrends such as demographic change, personalization, climate change or urbanization demand for increasingly flexible and mobile analytical measurement methods and assays. Especially in the environmental, agricultural, food and health sectors, chemical assays are a suitable choice. A large variety of such assays is available in the academic and industry area. However, their modification to measure new compounds is time-consuming and laborious, because they are typically designed to detect a specific single analyte. A modular platform for chemical assay development is thus highly desirable. Such a system should include the possibility for fast, easy and flexible implementation of various recognition types towards emerging analytes and the possibility for multi-parameter (multiplexed) detection in a potentially portable fashion. Single particle-based assays have proven to be an adequate solution here. In this work, I present hybrid polystyrene core-silica shell (SiO2@PS) particles as new spherical substrates for the flexible configuration of single particle-based chemical assays. First, a procedure to control the surface topology of the beads was developed, giving access to smooth, raspberry-like or multilayer-like CS structures. These particles were used for DNA detection down to the fmol-level (Chapter 2). A new tool to extract the roughness of the particles from electron microscopy images was developed next and applied to the wide range of CS beads prepared throughout the project (Chapter 3). This general protocol provides the basis for the comparability of future CS particle characterization. Finally, a multiplex assay with dye-encoded beads with non-fouling surfaces was developed to detect small molecules via immunochemical reactions in a wash-free procedure (Chapter 4). The latter ultimately proves that hybrid CS particles can combine high analytical performance and unmatched potential for flexible functionality.
Suspension Array Technology

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Khan, Ikram Ullah. "Microfluidic-assisted synthesis and release properties of multi-domain polymer microparticles drug carriers." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAF042/document.

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Les caractéristiques et les propriétés de libération de microparticules chargées de médicament dépendent de la nature des matériaux employés, des propriétés physicochimiques des microparticules, du choix de la méthode de production, et enfin des propriétés des molécules encapsulées. A l'inverse de la plupart des méthodes conventionnelles, les méthodes microfluidiques présentent l’avantage de bien mieux contrôler la génération de gouttelettes, leur taille et leur distribution de tailles. Ainsi des dispositifs microfluidiques à base de capillaires ont été développés pour obtenir des microbilles de polymère mais également des microparticules de type janus, coeur-écorce ou troyenne, toutes monodisperses en taille et chargées de médicament(s). Ces particules ont été produites à partir de solutions de monomère qui furent polymérisées par irradiations UV de telle sorte à garder intacte l'activité des molécules chargées. Ces dispositifs peuvent être assemblés dans un court laps de temps et un simple changement dans leur conception permet d’obtenir des morphologies de particules très différentes. Ces particules ont été développées dans le but de résoudre les problèmes rencontrés dans l’administration orale de médicaments. Par exemple les microbilles peuvent être utilisées pour délivrer des anti-inflammatoires non stéroïdiens de manière continue tandis que les particules Janus peuvent libérer, simultanément et sur le même site, deux principes actifs possédant des propriétés complètement différentes (solubilité, compatibilité) également de manière prolongée. Quant aux particules coeur-écorce, elles ont été conçues pour cibler la région du côlon de l'intestin humain, et y libérer simultanément deux médicaments. Les particules troyennes furent synthétisées à l’aide d’un procédé microfluidique semi-continu qui a permis une manipulation plus sécurisée des nanoparticules vectrices ainsi que la libération continue d’un médicament dans un liquide gastrique simulé. Chaque système a été entièrement caractérisé pour assurer l’invariance entre lots et la reproductibilité. En général, la libération des ingrédients actifs a pu être facilement contrôlée/ajustée par le réglage des paramètres opératoires et de matériaux tels que les débits des différentes phases, la nature et la concentration du médicament, des (co)monomères, des agents tensioactif et de réticulation, le pH du milieu de libération. Ces différents paramètres influencent les propriétés des microparticules telles que leur morphologie, forme, taille et densité de réticulation du réseau polymère
Characteristics and release properties of drug loaded microparticles depend upon material used and choice of production method. Conversely to most of the conventional ones, microfluidic methods give an edge by improving the control over droplet generation, size and size distribution. Capillary-based microfluidic devices were successfully used to obtain monodisperse drug(s) loaded microbeads, janus, core-shell and trojan particles using UV initiated free radical polymerization while keeping activity of active loaded molecules. These devices can be assembled in a short period of time and a slight change in design gives completely different microparticles morphologies. These particles were developed with the aim to address different issues experienced in oral drug delivery. For instance microbeads can be used to deliver NASIDs in a sustained release manner while janus particles can release two APIs with completely different properties (solubility, compatibility) also in a sustained release manner. Core-shell particles were designed to target colonic region of human intestine for dual drug delivery. Trojan particles were synthesized in a new semi-continuous microfluidic process, thus improving nanoparticles safety handling and release in simulated gastric fluid. Each system was fully characterized to insure batch to batch consistency and reproducibility. In general, the release of active ingredients was controlled by tuning the operating and material parameters like phases flow rates, nature and concentration of drug, (co)monomers, surfactant and crosslinker, pH of release media with the result of different particle morphologies, sizes and shapes or matrix crosslinking density

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Zhou, Xiamo. "OSTE Microfluidic Technologies for Cell Encapsulation and Biomolecular Analysis." Doctoral thesis, KTH, Mikro- och nanosystemteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217995.

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In novel drug delivery system, the encapsulation of therapeutic cells in microparticles has great promises for the treatment of a range of health con- ditions. Therefore, the encapsulation material and technology are of great importance to the validity and efficiency of the advanced medical therapy. Several unsolved challenges in regards to versatile microparticle synthesis ma- terials and methods form the main obstacle for a translation of novel cell therapy concepts from research to clinical practice. Thiol-ene based polymer systems have emerged and gained great popular- ity in material development in general and in biomedical applications specif- ically. The thiol-ene platform is broad and therefore of interest for a variety of applications. At the same time, many aspects of this material platform are largely unexplored, for example material and manufacturing technology developments for microfluidic applications . In this Ph.D. thesis, thiol-ene materials are explored for use in cell encap- sulation. The marriage of these two technology fields breeds the possibility for a novel microfluidic cell encapsulation approach using a novel encapsulation material. To this end, several new manufacturing technologies for thiol-ene and thiol-ene-epoxy droplet microfluidic devices were developed. Moreover, core-shell microparticle synthesis for cell encapsulation based on a novel co- synthesis concept using a thiol-ene based material was developed and inves- tigated. Finally, a thiol-ene-epoxy system was also used for the formation of microwells and microchannels that improve protein analysis on microarrays. The first part of the thesis presents the background and state-of-the-art technologies in regards to cell therapy, microfluidics, and thiol-ene based ma- terials. In the second part of the thesis, a novel manufacturing approach of thiol-ene-epoxy material as well as core-shell particle co-synthesis in micro- fluidics using thiol-ene based material are presented and characterized. The third part of the thesis presents the cell viability studies of encapsulated cells using the novel encapsulation material and method. In the final part of the thesis, two applications of thiol-ene-epoxy gaskets for protein detection mi- croarrays are presented.
Inkapsling av levande celler i mikrokapslar för terapeutiska ändamål är mycket lovande för frmatida behandling av många olika sjukdomar. Emeller- tid är en behandlings effektivitet i hög grad beroende av vilka material som används för inkapsling och vilken teknisk lösning som används för att ska- pa mikrokapslarna. För närvarande återstår det många utmaningar för att omvandla grundforskningresultat till klinisk verklighet, vilken kräver mer än- damålsenliga tillvägagångssätt för att tillverka mikrokapslar i material som är kompatibla med användningsområdena. De senaste åren har tiol-en baserade polymerer har blivit mycket använda för materialutveckling i stort och för biomedicinska tillämpningar i synnerhet. Med tiol-en kemi kan en mycket stor mängd helt olika syntetiska material framställas, vilket gör tiol-ener intressanta för en mängd applikationer. För närvarande är dock mycket inom denna materialklass outforskat, t.ex. inom material och tillverkningmetodik för mikrofluidiktillämpningar. I denna avhandling används tiol-ener för cellinkapsling. Sammanslagning av dessa teknologier möjliggör en ny typ av cellinkapsling med nya materi- alegenskaper. En mängd olika tillverkningssätt där tiol-en eller tiol-en-epoxi används för droplet-mikrofluidiksystem utvecklades. Core-shell mikrokapsel- syntes för cell-inkapsling baserat på en ny metod för samtidig syntes av både core och shell utvecklades och karaktäriserades. Slutligen utvecklades ett tiol- en-epoxi system för enkel integrering med proteinmikroarrayer på objektsglas. I avhandlingens första del presenteras bakgrund och dagens bästa teknolo- gier för terapeutisk cellinkapsling, mikrofluidik och tiol-en baserade material. I avhandlingens andra del presenteras en ny tillverkningsmetod för mikro- strukturerade tiol-en-epoxi artiklar och samtidig syntes av core och shell för mikrokapslar med användande av mikrofluidik. I den tredje delen presenteras cellöverlevandsstudier för de celler som inkapslats med de nya materialen och de nyutvecklade metoderna. I den avslutande delen beskrivs två specifika fall där tiol-en-epoxi komponenter används för proteindetektion och mikroarrayer.

QC 20171122

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Etmimi, Hussein Mohamed. "Hydrophobic core/shell particles via miniemulsion polymerization." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019/539.

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D'Souza-Mathew, Mark. "Responsive core-shell particles : synthesis & behaviour." Thesis, University of Leeds, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614644.

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Responsive core-shell particles have attracted considerable attention over the last decade due to requirements imposed on materials to be more suited for their environment, with the provision to react accordingly when it changes. The responsive component in these cases is a polymer shell, with the core mostly introducing a static dimension, functioning as a structural support, and in some cases providing an indicator of stability. Generally, medium solvency is the key driving force for the behaviour of environmentally responsive polymer shells. To date, numerous novel techniques for the construction of these hybrid particles have been presented, and these can he classified according to the pre synthesis state of the core and shell materials. In addition to responsive behaviour, dimensional control and density of the shell layer being good indicators of a viable method, it is becoming equally important from a green chemistry perspective to minimize processing times and the use of harmful solvents. This thesis describes two main studies: a novel method for the rapid synthesis of environmentally responsive core-shell particles in an aqueous medium, and the responsive behaviour of morphologically similar particles at the air-water interface. The former study exploits the responsive character of the shell polymer to facilitate rapid adsorption onto a the surface of a colloidal dispersion while preventing aggregation. The resultant core-shell particles acquire the character of the polymer, and exhibit cyclic responsiveness. The latter study describes the adsorption behaviour of similar core-shell particles. By manipulating the medium solvency, the interfacial affinity of these particles is probed, and when combined with desorption kinetics and compression studies, reveals how these particles may function when used as foam stabilizers.

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Wan, Wei. "Molecularly imprinted chromogenic and fluorogenic receptors as optical sensor matrix." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2015. http://dx.doi.org/10.18452/17261.

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Diese Dissertation befasste sich mit der Entwicklung von optischen Sensormaterialien für anionische Zielmoleküle durch die Kopplung der herausragenden Erkennungsfähigkeiten von molekular geprägten Polymere (molecularly imprinted polymers, MIPs) mit der Empfindlichkeit fluorometrischer Nachweisverfahren. In dieser Arbeit wurde dabei der direkte Einschritt-Nachweis für das Design der Sensormaterialien adaptiert. Hierbei wird eine Fluoreszenzsonde für die Signalübertragung kovalent in die Hohlräume der MIP-Matrix eingebaut. MIP-Sensormaterialien wurde in monolithischen, Dünnfilm- und Kern/Schale-Partikel-Formaten hergestellt. Die hergestellten Materialien wurden unter Verwendung unterschiedlicher Techniken charakterisiert. Die Performanz der Sensormaterialien wurde auch in Bezug auf die Sensitivität, Selektivität sowie Ansprechzeit bewertet. In dieser Arbeit wurden dabei Systeme untersucht, bei denen die Signalerzeugung sowohl auf dem „Einschalten“ als auch auf dem „Ausschalten“ der Fluoreszenz beruhte. Mit den hergestellten Materialien wurden dabei viele Ziele des Projekts erreicht. Sowohl die synthetisierten dünnen Filme als auch die Kern/Schale-Partikel zeigten eine hohe Selektivität für die geprägten Aminosäuren, auch in Bezug auf die Unterscheidung von Enantiomeren. Diese Sensormaterialien waren ebenfalls durch eine niedrige Nachweisgrenze bis 60 µM und eine schnelle Ansprechzeit von 20 Sekunden gekennzeichnet. Insbesondere die Kern/Schale-Partikel können mit verschiedenen Detektionstechniken gekoppelt werden und sind potentiell für die Entwicklung von miniaturisierten Messinstrumenten für die on-line-Detektion sowie Point-of-Care-Diagnostik (patientennahe Labordiagnostik) einsetzbar.
This dissertation derives from the DFG project aimed on preparing optical sensor material for anionic target through combing the outstanding recognition of Molecularly imprinted polymer (MIPs) and sensitive fluorescence technique. A single step direct sensing strategy is adopted to prepare the sensor material in this thesis. Here, a fluorescence probe is covalently embedded into the MIP cavity for signal transduction. MIP sensor material are prepared in forms of bulk, thin film and particles. The material is characterized using various techniques. The performance of the sensor materials is also assessed in terms of sensibility, selectivity as well response time. Both the switching on and off signaling methods are tested in this thesis. The prepared material achieves the goal of the project. Both the prepared thin film as well as core-shell particle show prominent selectivity even a strong enantioselective discrimination. These sensing materials also have low LOD to 60 µM and fast sensing response of 20 seconds. Especially the core-shell sensing particle can be coupled with various detection techniques and is potentially applicable for developing miniaturized sensing instrument for on-line detection as well as point of care diagnose.

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Horecha, Marta. "Coatings with Inversely Switching Behavior. New Applications of Core-Shell Hydrogel Particles." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-65171.

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The main goal of this work is design and synthesis of novel composite hydrogel-based core-shell microparticles and their application for fabrication of coatings, which provide the “inverse-switching” behaviour to the surface, namely, to become more hydrophobic in water environment. Since contact angle of heterogeneous surfaces is dependent on the nature and ratio of surface components, an increase of amount of more hydrophobic component on the surface will cause the reducing of surface wettability. It was suggested that core-shell particles having water-swellable hydrogel core and hydrophobic, but permeable for water shell when deposited on the hydrophilic substrate should increase the total amount of hydrophobic component on the surface when the cores of particles will swell in water. During the work different approaches to obtain freely dispersed and surface-immobilized core-shell particles with required structure were developed. Obtained particles were applied for preparation of coatings with ability to display “inverse-switching” behaviour. It was demonstrated that properly designed and properly prepared core-shell particles could be successfully used for creation of smart adaptive coatings having the ability to alter the surface properties upon changing of the environment.

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Khazeni, Nasser. "Synthesis And Characterization Of Zirconium Tungstate-zirconia Core-shell Composite Particles." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615316/index.pdf.

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Thermal mismatch between different components of a system could cause of problems like residual stress induced cracking, thermal fatigue or even optical misalignment in certain high technology applications. Use of materials with customized thermal expansion coefficient is a counter-measure to resolve such problems. Zirconium tungstate (ZrW2O8) with negative thermal expansion coefficient is capable of being used in synthesis of composites with tailored coefficient of thermal expansion (CTE). In this work, the sol-gel method which had been already set up in our group was characterized and the sources of the factors imposing impurities in the product were distinguished in all the steps of precursor preparation and heat treatment. In the second part of study, zirconium tungstate particles synthesized by the sol-gel method were utilized as core in synthesis of ZrW2O8&ndash
ZrO2 core&ndash
shell composite particles. Shell layer was composed of ZrO2 nanocrystallites and precipitated from an aqueous solution by urea hydrolysis. Volume of the shell was effectively controlled by concentration of the initial zirconium ion in the solutions. The rate of precipitation was a function of the ratio of initial urea concentration to zirconium ion. It is hypothesized that isolation of the ZrW2O8 within a layer of ZrO2, will be a key element in solving problems associated with reactivity of ZrW2O8 towards other components in sintering of ceramic&ndash
ceramic composites with tuned or zero thermal expansion coefficient.

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15

Arnal, Pablo Maximiliano. "The synthesis of monodisperse colloidal core @shell spheres and hollow particles." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=981080596.

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16

Mao, Jifu. "Functional polypyrrole core-shell particles and flexible membranes for biomedical applications." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27861.

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Le polypyrrole (PPy), l'un des polymères conducteurs de type p, a démontré un potentiel considérable dans les applications biomédicales et le stockage d'énergie en raison de sa conductivité électrique intrinsèque, sa facilité de synthèse, son potentiel de modification chimique et sa biocompatibilité. En raison de la conjugaison étendue dans ses chaînes moléculaires et de son état d'agrégation, les mauvaises propriétés mécaniques et le manque de processabilité du PPy ont été des défis scientifiques et technologiques exceptionnels. En outre, le PPy possède une bioconductivité, mais aucune bioinductivité, c'est-à-dire une absence de biofonctionnalité, ce qui constitue un autre défi pour le PPy lorsqu'il est utilisé pour des applications biomédicales. Cette thèse se concentre principalement sur ces deux défis auxquels le PPy fait face, c’est-à-dire le manque de biofonctionnalité et la mauvaise performance mécanique. En se basant sur la différence des réactivités chimiques des comonomères, les particules de poly(pyrrole-co-(1- (2-carboxyéthyl)pyrrole structurées en noyaux-coquilles (P(Py-PyCOOH)) ont été synthétisées. Elles sont constituées d'un noyau composé d’un copolymère de P(Py-PyCOOH) riche en PPy et d'une coque composée de PPy-COOH. Les paramètres expérimentaux de polymérisation en émulsion ont été étudiés pour définir les conditions optimales. L'anticorps d’albumine de sérum humain (anHSA), en tant que molécule modèle a été immobilisé par des liaisons covalentes sur la surface des particules et a été prouvé réactif aux antigènes. Un schéma a été proposé pour illustrer la formation des particules de cœur-coquille (P(Py-PyCOOH)) selon un nouveau mécanisme basé sur les réactivités du comonomère. Cette méthode de fabrication peut permettre de préparer des particules de PPy fonctionnelles en grande quantité. La chimie de surface et de masse, la conductivité et le rendement global des particules peuvent être régulés. Pour la première fois, une membrane en PPy souple et mécaniquement traitable (PPy-N) a été préparée par polymérisation interfaciale assistée par modèle (TIP) sans modification chimique des monomères ni autres matériaux. Les structures uniquement interconnectées et multicouches ont été considérées comme responsables de l'excellente souplesse aux températures ambiante et à -196 °C. Un mécanisme basé sur la nature exothermique de la polymérisation du pyrrole a été suggéré pour expliquer les morphologies du PPy-N. Cette membrane en PPy flexible a un poids léger (9 g m-2), une grande surface (14,5 m2 g-1), un comportement électrothermique stable, une amphiphilicité et une excellente cytocompatibilité. Enfin, une nouvelle approche modulaire a été proposée pour immobiliser les protéines sur une surface micro/nano structurée. L'albumine de sérum bovin (BSA) et la HSA ont été immobilisées de manière covalente sur la surface des particules (P(Py-PyCOOH) avant qu’elles soient assemblées sur la surface de la membrane PPy-N pour construire une surface biofonctionnée avec la coexistence de deux types de biomolécules. Cette approche sépare la greffe de protéines et l'immobilisation en deux étapes indépendantes, fournissant ainsi une méthode simple et hautement flexible pour concevoir et fabriquer une surface ou un échafaudage multi-biofonctionnalisé.
Polypyrrole (PPy), one of p-type conducting polymers, has shown considerable potential in biomedical applications and energy storage owing to its inherent electrical conductivity, ease of synthesis, possibility of further chemical modification, and biocompatibility. Due to the extensive conjugation in PPy chains and the aggregation state, the poor mechanical property and processability of pristine heterocyclic PPy have been the outstanding scientific and technological challenges. Moreover, PPy only possesses bioconductivity but no bioinductivity, i.e., lack of biofunction, which is another challenge for PPy when it is applied in biomedical applications. This thesis mainly focuses on these two issues of PPy, i.e., the lack of biofunctionality and the poor mechanical performance. Based on the difference in comonomer reactivity, the core-shell structured poly(pyrrole-co-(1-(2-carboxyethyl)pyrrole)) (P(Py-PyCOOH)) particles were synthesized, comprising the pyrrole (Py) dominated P(Py-PyCOOH) copolymer as the core and PPyCOOH homopolymer as the shell. Experimental parameters of emulsion polymerization were investigated to define the optimal conditions. Anti-human serum albumin antibody (anHSA) as a model molecule was covalently immobilized onto the particle surface and proven reactive to its antigen. A schema was proposed to illustrate the formation of the core-shell (P(Py-PyCOOH)) particles based on a new reactivity-driven mechanism. This fabrication method can be used to prepare functional PPy particles in large-scale. The surface and bulk chemistry, conductivity, and the overall yield of the particles can be regulated. For the first time, a soft and mechanically processable PPy membrane (PPy-N) was prepared by template assisted interfacial polymerization (TIP) with neither chemical modification of the monomers nor compounding with any other materials. The uniquely interconnected and multilayered structures were considered responsible for the excellent flexibility at both room temperature and -196 °C. A mechanism based on the exothermic nature of pyrrole polymerization was suggested to explain the morphology of the PPy-N. Such a flexible PPy membrane has lightweight (9 g m-2), large surface area (14.5 m2 g-1), stable electrothermal behavior, amphiphilicity, and excellent cytocompatibility. Finally, a novel modular approach was proposed to immobilize proteins to a micro/nano structured surface. Bovine serum albumin (BSA) and HSA were covalently immobilized onto the surface of the (P(Py-PyCOOH)) particles prior to their assembly onto the surface of the PPy-N membrane, to construct a biofunctionalized surface with the coexistence of two types of biomolecules. This approach separates protein grafting and immobilization into two independent steps, providing an easy and highly flexible method to design and fabricate multi-biofunctionalized surface or scaffold.

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17

Jiang, Chengliang. "Germania-based Sol-gel Coatings and Core-shell Particles in Chromatographic Separations." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7683.

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Chapter one reviewed the development of sol-gel stationary phase for gas chromatograph (GC). Inorganic sol-gel precursor creates the substrate support for stationary phase bind to silica surface through the condensation of silanol groups, the rough surface with enhanced surface area enlarger the capacity of the sol-gel stationary phase, the porosity of sol-gel structure decreases the mass transferring coefficient, the term C in Van Deemter equation, which makes sol-gel stationary phase thicker coating up to 1 um but keeps the high resolution for gas chromatography. Chemical bound stationary phase significantly improve GC column with better thermal stability and solvent stability. Partial derivatizations of known polymers have not increased the column performance but remained at the same level of 3200 plates per meter. The sol-gel chemistry with essential structure rebuilding will make sol-gel stationary phase to a new level. The chapter two reported the non-silica-based metal alkoxide oxide as the new building block, cooperated with known polymer poly(dimethyldiphenylsilanoxan), developed the original nonpolar feature of the stationary phase to broad the polarity from the nonpolar to extreme polar, overcome the thermal stability for other types of polar column. The theoretical plate number reached the 3200 plates per meter, and the optimized plate number arrived at the top level at 3800 plates per meter. The basic recipe and preparation of sol-gel process were verified by tungsten alkoxide incorporated with poly(dimethyldiphenylsilanoxan) as the stationary phase which arrived the same plate number level at 3800 per meter. Chapter three demonstrated the preparation of core-shell particle for HPLC. Conventional silica core particles were prepared with stÖbe methods. The extended layer of germanium oxide coating was made with acid and alkaline as a catalyst. EDS characterize the extended layers of germanium oxide has been coated at ratio 12/1(Ge/Si). Then the carbon loading with C 18 for surface derivatization were also confirmed with EDS testing. 2 um core-shell particles were successfully prepared from the external composition (1.7 um core, 0.3 um shell). The function of the core-shell particles was slurry packed with 5cm regular steel column and the capillary column with sol-gel frit. The preliminary HPLC testing showed the core-shell particles had more retention ability compare with 4 um commercial core particles. The backpressure of the short steel column and capillary both were beyond the pressure limit of conventional HPLC pump. Chapter three demonstrates the new ideal of the surface sol-gel process for GC stationary phase. Without the catalyst, the sol solution has constant viscosity and gelation time is much longer, the sol-gel reaction was taking on the silica surface only, to accomplish the thinner coating for sol-gel stationary phase. From the retention time of the grob mixture, the surface sol-gel coated 2 meters of column acquired the half retention time, grob mixture analytes were eluted within 7 minutes, compared with conventional sol-gel coated column eluted within 14 minutes. Without the TFA as the catalyst, the sol-gel matrix may not form effective surface area and porosity to support the functional polymer for separation, the column performances were two third of the protocol column, at 1500-2500 plate number per meter. The coating results proved the sol-gel stationary phase could be fulfilled with diluted sol solution by static coating. Basic parameters for dynamic coating and static coating with conventional coating and surface sol-gel were acquired for further development. The germania and niobium precursor is highly active, the water amount in the solvents used as received without drying process can meet the surface sol-gel coating without precipitates and gelation formed before finishing coat. For germania -PDMDPS column, thermal stability is very important because of the temperature for remaining the low residual OH- group in silica and germania film at 350 °C.

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18

Kelly, Laura. "The release of pro-angiogenic growth factors from core-shell polymer particles." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/10100/.

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Angiogenesis is the formation of new blood vessels from a pre-existing vascular network. Angiogenesis is stimulated by proteins called growth factors. Growth factors have been used to treat ischemic tissue for some time. When they were first used to induce angiogenesis, application of a single growth factor was used; this had limited success. Hence, there has been a move towards releasing two or more pro-angiogenic growth factors to induce blood vessel formation. Three growth factors were investigated: vascular endothelial growth factor (VEGF); platelet derived growth factor (PDGF); and endothelial growth factor (EGF). These growth factors were chosen due to potential for binding and, to a lesser extent, for size variation. Two novel systems have been developed that can successfully bind and release various heparin binding proteins by electrostatic binding of the growth factors on to or within the outer layer of polymer particles. It has been concluded that the protein size and the shell architecture have the main effect upon the release profile of the proteins.

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19

Chabrol, Virginie. "Functionalized latex particles as substrates for metal mediated radical polymerization." Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-01012004.

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Le sujet de cette thèse consiste à incorporer une couronne de polymère hydrophile à la surface de particules de latex par amorçage et croissance en utilisant la polymérisation radicalaire contrôlée par transfert d'atome induite par les métaux. Les particules de latex, obtenues par, polymérisation radicalaire en émulsion ont été fonctionnalisées avec un " inimère ", monomère comportant une fonction halogénée capable de jouer le rôle d'amorceur dans l'étape de greffage. Cette étape de greffage a ensuite été effectuée en présence de CuBr2, PMDETA et d'un métal à valence zéro tel que le cuivre, àtempérature ambiante à partir de latex non post-purifiés (présence de tensio-actif et d'amorceur résiduels et à taux de solide élevés). Au cours du processus, l(incorporation de l'inimère et de la couronne hydrophile a été vérifée par ToF-SIMS (time-of-light secondary ion mass spectrometry), par FTIR et par l'étude des propriétés colloïdales des latex greffés.

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20

Tait, James Robert. "Optical trapping of colloidal core-shell particles in organic solvents and in liquid crystals." Thesis, University of Bristol, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445881.

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21

Menzel, Cristian. "Polyelectrolyte core/hydrophobic shell polymer particles by double emulsion templating polymerisation for environmental applications." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/polyelectrolyte-corehydrophobic-shell-polymer-particles-by-double-emulsion-templating-polymerisation-for-environmental-applications(0fa106d3-770c-48e0-9f4e-7ba29ae9caf1).html.

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Herein two novel synthetic strategies for the synthesis of sub-millimetre sized core–shell particles comprising a polyelectrolyte core and a porous hydrophobic shell are presented. In the first method, a water-in-oil-in-water (W/O/W) double-emulsion was used as a template for the simultaneous polymerisation of both the internal aqueous and the intermediate oil phases, via suspension polymerisation, leading to the formation of a cross-linked poly(acrylic acid-co-bisacrylamide) core contained in a porous poly(4-tert-butylstyrene-co-divinylbenzene) shell. It was found that the formation of core–shell morphology was favoured by the effect of acrylic acid which was responsible for the selective destabilization of the internal aqueous/oil (W/O) interface. It was found that rapid internal phase coarsening promoted the formation of single-core structures. A rapid gel-point of the oil phase, on the other hand, reduced the internal aqueous phase diffusion towards the external phase. The detrimental effect over internal emulsion stability was replicated using ethanol, 2-propanol, n-butanol and propionic acid which were used as a co-solvent in the internal aqueous phase to promote core/shell morphology formation. The second method involved the use of a flow-focusing device for the formation of monodisperse W/O/W emulsion droplets which were photo-polymerised. Anionic poly(sodium acrylate), poly(sodium vinyl sulfonate), and cationic poly(3-acrylamidopropyl)trimethylammonium chloride) hydrogels were encapsulated within a porous poly(trimethylolpropane triacrylate-co-methyl methacrylate) shell. Control over both particle diameter and shell thickness was achieved by tuning the flow rates of the different phases. The use of these novel hydrogel core/shell particles as novel material for environmental applications, including the scavenging of radionuclides, was investigated. It was found that hydrophilic substances including dyes and metal ions were rapidly adsorbed and encapsulated within the core region after diffusing through the permeable porous shell. Part of the results obtained in this work have been published in the article J. Mater. Chem. A, 2013, 1, 12553-12559.

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22

San, San Maw. "Synthesis of Silver Nanoshells with Controlled Thickness and Morphology." Doctoral thesis, Kyoto University, 2020. http://hdl.handle.net/2433/245847.

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京都大学
0048
新制・課程博士
博士(工学)
甲第22162号
工博第4666号
新制||工||1728(附属図書館)
京都大学大学院工学研究科化学工学専攻
(主査)教授宮原稔, 教授山本量一, 教授松坂修二
学位規則第4条第1項該当
Doctor of Philosophy (Engineering)
Kyoto University
DGAM

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23

Dubey, Nidhi Chandrama. "Smart hydrogels based platforms for investigation of biochemical reactions." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-184082.

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Polyketides are natural products with complex chemical structures and immense pharmaceutical potential that are synthesized via secondary metabolic pathways. The in-vitro synthesis of these molecules requires high supply of building blocks such as acetyl Co-enzyme A, and cofactors (adenosine triphosphate (ATP). These precursor and cofactor are synthesized from respective soluble enzymes. Owing to the expensive nature of the enzymes, it is important to immobilize enzymes to improve the process economics by enabling multiple uses of catalyst and improving overall productivity and robustness. The polymer-based particles of nano and submicron size have become attractive material for their role in the life sciences. With the advances in synthetic protocols of the microgels and commercial availability of many of the monomers, it is feasible to tune the properties of the particles as per the process requirement. The core shell microgel with functional shell allows high loading of ligands onto the microgel particles due to increased availability of functional group on the outer surface. The aim of the thesis thus was to study biochemical reactions on the smart microgels support using single (acetyl CoA synthetase (Acs)) and dual (pyruvate kinase (Pk) and L-lactic dehydrogenase (Ldh)) enzyme/s systems. The study indicated that the enzyme immobilization significantly depends on the enzyme, conjugation strategy and the support. The covalent immobilization provides rigidity to the enzyme structure as in case of Acs immobilized on PNIPAm-AEMA microgels but at the same time leads to loss in enzyme activity. Whereas, in the case of covalent immobilization of Ldh on microgel showed improved in enzyme activity. On the other hand adsorption of the enzyme via ionic interaction provide better kinetic profile of enzymes hence the membrane reactor was prepared using PNIPAm-PEI conjugates for acetyl CoA synthesis. The better outcome of work with PNIPAm-PEI resulted in its further evaluation for dual enzyme system. This work is unique in the view that the immobilization strategies were well adapted to immobilize single and dual enzymes to achieve stable bioconjugates for their respective applications in precursor biosynthesis (Acetyl Co enzyme A) and co-factor dependent processes (ACoA and ATP). The positive end results of microgels as the support (particles in solution and as the thin film (membrane)) opens further prospective to explore these systems for other precursor biomolecule production.

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24

Kundt, Matthias [Verfasser]. "Magnetoresponsive liquid crystalline systems based on elongated core-shell particles in nematic phases / Matthias Kundt." München : Verlag Dr. Hut, 2018. http://d-nb.info/1162767863/34.

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25

Brasse, Yannic [Verfasser], Andreas [Gutachter] Fery, and Nikolai [Gutachter] Gaponik. "Coupled Plasmonic Nanostructures Based on Core-Shell Particles / Yannic Brasse ; Gutachter: Andreas Fery, Nikolai Gaponik." Dresden : Technische Universität Dresden, 2020. http://d-nb.info/1227201362/34.

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26

Chen, Jing. "Toughening epoxy polymers and carbon fibre composites with core-shell particles, block copolymers and silica nanoparticles." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/14261.

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Epoxies are a class of high-performance thermosetting polymers which have been widely used in many industrial applications. However, unmodified epoxies are susceptible to brittle fracture due to their highly crosslinked structure. As a result, epoxies are normally toughened to ensure the feasibility of these materials for practical applications. Recently, a new generation of toughening agents such as polysiloxane based core-shell rubber (CSR) particles, amphiphilic block copolymers and silica nanoparticles have been developed to toughen epoxies. These new toughening agents will be studied in this thesis to pursue ultra-tough and stiff epoxies without compromising other desirable properties. Polysiloxane based CSR particles were able to toughen an anhydride cured epoxy over a wide range of temperatures from -109 °C to 20 °C. At -109 °C, the fracture energy of the epoxy could still be increased from 174 to 481 J/m2 with the addition of 20 wt% of the CSR particles. The toughening mechanisms of these CSR particle modified epoxies were identified as shear band yielding and plastic void growth. A series of commercial poly(methyl methacrylate)-b-poly(butylacrylate)-b-poly( methyl methacrylate) (MAM) triblock copolymers were studied as toughening agents in two epoxy systems. The fracture toughness was generally increased by these block copolymers, although their toughening performance was dependent on the crosslink density of the epoxies and the morphologies of the modified epoxies. The MAM modified epoxies were also studied as the matrix materials in fibre-reinforced composites to investigate the transfer of toughness from the matrix materials to the composites. Full (1 to 1) and nearly full toughness transfer was obtained for the composites. Hybrid toughening using a combination of the MAM block copolymer and silica nanoparticles has also been investigated in the same epoxy systems. The addition of the silica nanoparticles further increased the toughness of the MAM modified epoxies if micron-sized MAM particles present.

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27

Chamradová, Ivana. "Polymerní materiály pro řízenou administraci léčiv a řízené uvolňování aktivních látek." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-233407.

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Literární rešerše předložené dizertační práce shrnuje poznatky jak o současně používaných biomateriálech, tak i o tzv. „chytrých“ biomedicínských materiálech mezi které patří termocitlivé kopolymery. Mezi tyto kopolymery, jejichž vodné roztoky gelují při teplotě lidského těla (37 °C), řadíme amfifilní triblokové kopolymery skládající se z hydrofobního laktidu, glykolidu a hydrofilního polyethylen glykolu (PLGA PEG PLGA). Komerčně dostupné termocitlivé kopolymery známé pod názvem ReGel or OncoGel jsou v současné době využívány jako injekčně aplikovatelné nosiče s postupným uvolňováním léčiv, zejména při léčbě cukrovky nebo onkologického onemocnění. Nicméně PLGA PEG PLGA triblokový kopolymer může být použit I jako polymerní nosič anorganického léčiva případně jako biodegradabilní implantát v dentálních či ortopedickýchých aplikacích. Z toho důvodu byl vybrán anorganický biokompatibilní hydroxyapatit (HAp) pro své majoritní zastoupení v tvrdých tkáních. Experimentální část je zaměřena na přípravu HAp/PLGA PEG PLGA kompozitů, ve kterých je HAp buď ve formě nano- (n-HAp) nebo „core-shell“ částic (CS). Nové CS částice, připravené dvouemulzní metodou, jsou složeny z „tuhého“ HAp jádra obaleného termocitlivým kopolymerem, který je navíc funkcionalizován kyselinou itakonovou (ITA/PLGA PEG PLGA/ITA). Funkcionalizace pomocí ITA vnáší do původní struktury kopolymeru jak síťovatelné dvojné vazby, tak i koncové karboxylové skupiny. Volné karboxylové skupiny na koncích ITA/PLGA PEG PLGA/ITA kopolymerního obalu byly dále zesíťovány za vzniku 3D chemické sítě (CS-x), jejíž životnost je řízena a kontrolována. ATR-FTIR spektroskopie prokázala přítomnost „nových“ esterových vazeb vzniklých karbodiimidovou reakcí –OH a –COOH skupin, kterým náleží adsorpční pásy ve vlnové délce 1021 cm-1.. n-HAp a CS-x částice byly přidány do kopolymerní termocitlivé matrice (PLGA PEG PLGA) za účelem charakterizace jejich reologického chování. Bylo zjištěno, že pokud bylo do polymerní matrice přidáno méně než 10 hm. % CS-x částic a jen 5 hm.% n-HAp kompozit si zachoval své termocitlivé vlastnosti. Na druhou stranu, přídavek vyššího množství HAp částic do polymerní matrice zajistil změnu vodného polymerního solu v permanentní gel při teplotě nad 37 °C. Analýza ICP-OES prokázala rychlejší uvolňování CS-x částic z 10 hm/obj. % PLGA PEG PLGA polymerní matrice do inkubačního média (6 % 9. den) než tomu bylo u n-HAp částic (jen 3 %), které jsou vázány více v micelární struktuře kopolymeru. Proto, kompozit na bázi n-HAP částic tvořící tuhý trvalý gel při tělesné teplotě, je vhodný více jako biologicky rozložitelné kostní lepidlo, zatímco kompozit z CS-x částic a termocitlivého kopolymeru je vhodný jako nosič léčiv pro injekční aplikace.

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Gretz, Markus. "Synthese und kolloidchemische Eigenschaften hybrider core-shell Partikel und ihre mögliche Anwendung in der Bauchemie." München Verl. Dr. Hut, 2010. http://d-nb.info/100224370X/04.

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29

Ya, Wang Tzu, and 王姿雅. "Nanometer Scale Core/Shell Rubber Particle." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/17388297409145883865.

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碩士
輔仁大學
化學系
89
Epoxy resin is the widely used engineering polymer. However their toughening properties are very poor. Using core-shell particle techniques can solve the problem. In our study, the nanometer core-shell latex particles are prepared using emulsion polymerization. About the silicon rubber core, owing to it superior flexibility and thermal stability, are prepared by emulsion polymerization of polydimethylsiloxane (PDMS), tetraethylorthosilicate (TEOS), and γ-methacryloxy propytrimthoxysiloxane (γ-mps) in the presence of tin catalyst and emulsifier. The shell composed of polymethylmethacrylate (PMMA) and crosslinked with diethyleneglycoldimethacrylate (DEGDM). We used the light scatter and TEM to analysis the core / shell rubber particle size, is 15 nm. The FT-IR shows that we deleted the SDS from the aqueous and PMMA covered the soft core. Observed the fracture face by SEM. The tensile stress and Young’s modulus of nano particle lost less than the micro particle. The toughening behavior are similar with the micro particle.

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30

Tsan-WenChen and 陳燦文. "Optimization of transferring and releasing process for core-shell Ga-particle pastes." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/5p2cu5.

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Chang, Rong-wei, and 張容瑋. "Synthesis of Core-Shell Rubber and Inorganic/Organic Core-Shell Particle as Additives by RAFT Living Free Radical Polymerizations for Unsaturated Polyester Resins." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/50076239174702272605.

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碩士
國立臺灣科技大學
化學工程系
96
Synthesis of inorganic/organic core-shell particle (CSP) as low-profile additives for unsaturated polyester resins by RAFT living free radical polymerizations has been studied in this work. Before the RAFT polymerization, the chain transfer agent with a chemical structure of Z-C(=S)-S-R was synthesized first. The synthesized chain transfer agent was then characterized by using FTIR、1H-NMR and DSC to confirm its structure. The chain transfer agent (CTA), namely, BSPA, was bonded onto the inorganic silica particles. The silica-supported BSPA was then used to mediate RAFT polymerization of methyl acrylate to produce homopolymer grafted silica, known as inorganic/organic core-shell particle (CSP). It was found that the introduction of a free CTA in solution during polymerization could significantly improve the control on molecular weight and polydispersity of grafted polymers.

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32

Liou, Chien Wei, and 劉鑒蔚. "The effect of inorganic filler and core shell rubber particle in epoxy resin (II)." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/82712065895505215432.

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碩士
國立中央大學
化學工程學系
85
In order to increase the toughness in cured epoxy ressin, many kind of inorganic filler and rubber were dispersed therein prior to curing. But both used filler and rubber to increase the fracture energy were less in literature. Here we synthesize core shell rubberparticle by emulsifer free polymerization for shell content poly(methyl methacrylate/ methacrylic acid) and core content poly(butylacrylate).the core shell rubber particle also content 5% crosslink agent in shell and 3% in core to prevent swellen if we use solvent to disperse it in epoxy resin.Blend core shell rubber particle with magnesium hydroxide(0.6um) andaluminum powder(>1um) in DGEBA/dicy resinsystem, we got different result in fracture energy.It seem be caused by high crosslink density of core shell rubber particle and different colagulation extent of magnesium hydroxide and aluminum powder. The majortoughening mechanism should be crack deflection.

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33

HUNG, WU CHIA, and 吳嘉鴻. "Synthesis of core-shell particle with acrylic rubber as the core soapless emulsion polymerization to toughen unsaturated polyester resins." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/16850463123458724974.

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34

徐曼紋. "Effect of core-shell particle on the cure kinetics and glass transition temperature for unsaturated polyester resins." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/49312385872456442897.

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35

Chen, Hsiao-Lan, and 陳曉蘭. "Effects of nano-scale and submicron-scale core-shell rubber additives, inorganic silica gel/organic polymer core-shell particle, and montmorillonite clay on the cured sample morphology ,volume shrinkage, internal pigmentability, and mechanical properties." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/04232091512842434823.

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碩士
國立臺灣科技大學
化學工程系
98
The effects of four additives, including (1) nano- scale and submicron-scale core-shell rubber additive,(2) inorganic silica gel/organic polymer core-shell particle, (3) montmorillonite clay and (4)Raft CSR, on the cured sample morphology, volume shrinkage characteristics and , mechanical properties of the styrene(St)/ Vinyl ester resin (VER)/ additives ternary systems and Epoxy/curing agent /additive ternary systems after the cure have been investigated. The experimental results have been explained by integrated measurements combining phase characteristic of the St/VER/additive ternary system and Epoxy/curing agent /additive ternary systems before the cure, XRD analysis , cured sample morphology, final cure conversion, and volume fraction of microvoid generated during the cure by using DSC , SAXS , WAXS , SEM , TEM , OM and image analysis. Also the scattering intensity of vinyl ester resin (VER) and unsaturated polyester (UP) with different structure in dilute styrene solution was measured by the method of small angle X-ray scattering (SAXS), and the radius of gyration of VER and the UP molecule can then be calculated by using the Guinier law. ( keywords: core-shell rubber(CSR); montmorillonite (MMT); volume shrinkage;internal pigmentability;unsaturated polyester(UP); vinyl ester resin (VER)；curing；mechanical properties；radius of gyration)

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36

Chang, Han-Wen, and 張瀚文. "Effects of nano-scale and submicron-scale core-shell rubber additives, inorganic silica gel/organic polymer core-shell particle, and montmorillonite clay on the cured sample morphology, volume shrinkage, internal pigmentability ,and mechanical properties." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/29214729275413454738.

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碩士
國立臺灣科技大學
化學工程系
97
The effects of two additives, including (1) nano- scale and submicron-scale core-shell rubber additive,(2) inorganic silica gel/organic polymer core-shell particle, and (3) montmorillonite clay, on the cured sample morphology, volume shrinkage characteristics and internal pigmentability, mechanical properties of the styrene(St)/ Vinyl ester resin (VER)/ additives ternary systems and Epoxy/curing agent /additive ternary systems after the cure have been investigated. The experimental results have been explained by integrated measurements combining phase characteristic of the St/VER/additive ternary system and Epoxy/curing agent /additive ternary systems before the cure, XRD analysis , cured sample morphology, final cure conversion, and volume fraction of microvoid generated during the cure by using DSC , SAXS , WAXS , SEM , TEM , OM and image analysis. Also the scattering intensity of vinyl ester resin (VER) and unsaturated polyester (UP) with different structure in dilute styrene solution was measured by the method of small angle X-ray scattering (SAXS), and the radius of gyration of VER and the UP molecule can then be calculated by using the Guinier law.

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37

Chiu, Shu-wei, and 邱淑微. "Effects of nano-scale and submicron-scale core-shell rubber additives, inorganic silica gel/organic polymer core-shell particle, and montmorillonite clay on the cure kinetics, glass transition temperatures, volume shrinkage, mechanical properties and cure." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/16096561528870591250.

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碩士
國立臺灣科技大學
化學工程系
99
The effects of four additives, including (1) nano- scale and submicron-scale core-shell rubber additive,(2) inorganic silica gel/organic polymer core-shell particle, (3) organic montmorillonite clay, on the cure kinetics, glass transition temperatures, cured sample morphology, volume shrinkage characteristics and mechanical properties of the Styrene(St)/ Unsaturated polyester (or Vinyl ester resin)/ additives ternary systems and Epoxy/curing agent /additive ternary systems after the cure have been investigated. The experimental results have been explained by integrated measurements combining phase characteristic of the St/VER/additive ternary system and Epoxy/curing agent /additive ternary systems before the cure, final cure conversion, glass transition temperature, SAXS and WAXS analysis, cured sample morphology and Mechanical properties. Also the scattering intensity of vinyl ester resin (VER) and unsaturated polyester (UP) with different structure in dilute styrene solution was measured by the method of small angle X-ray scattering (SAXS), and the radius of gyration of VER and the UP molecule can then be calculated by using the Guinier law.

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38

Oktavia, Hyurin, and 林優恩. "Effects of Nano-scale and Submicron-scale Core-shell Rubber Additives, Inorganic Silica/Organic Polymer Core-shell Particle, and Montmorillonite Clay on the Cure Kinetics, Glass Transition Temperatures, Volume Shrinkage, and Internal Pigmentability for Un." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/56957295543964945444.

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碩士
國立臺灣科技大學
化學工程系
98
The effects of nano-scale and submicron-scale core shell rubbers (CSR), inorganic silica gel/organic polymer core-shell particle (CSP), silane-treated montmorillonite clay (MPSi-MMT) and alkyl-ammonium treated montmorillonite clay (AMMT) as low-profile additives (LPA) on the cure kinetics, glass transition temperatures and volume shrinkage for styrene (ST)/unsaturated polyester (or vinyl ester)/additive ternary systems and epoxy/curing agent/additive ternary systems have been investigated. The reaction kinetics during the cure was measured by Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectrometry (FTIR). Based on the Takayanagi mechanical models, the glass transition temperature in each region of the cured samples for ST/UP (or VER)/additive ternary systems and epoxy/curing agent/additive ternary systems was measured by the Dynamic Mechanical Analysis (DMA). The volume shrinkage of the cured sample was also measured using the density method. (Keyword: core-shell rubber (CSR) ; low-profile additive (LPA) ; montmorillonite (MMT) ; unsaturated polyester (UP) ; vinyl ester resin (VER) ; epoxy resin；curing kinetics ; glass transition temperature ; volume shrinkage)

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39

HSU, Ting-Yu, and 許廷宇. "Effects of nano-scale and submicron-scale core-shell rubber additives, inorganic silica gel/organic polymer core-shell particle, and montmorillonite clay on the cure kinetics and glass transition temperatures for unsaturated polyester, vinyl ester, and ep." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/98969309854803471161.

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碩士
國立臺灣科技大學
化學工程系
97
Abstract The effects of nano-scale and submicron-scale core shell rubbers (CSR) as low-profile additives (LPA), and inorganic silica gel/organic polymer core-shell particle,and silane treated montmorillonite clay (MMT) on the cure kinetics and glass transition temperatures for styrene/unsaturated polyester (or vinyl ester) /additive ternary systems and epoxy/curing agent /additive ternary systems have been investigated. The reaction kinetics for the ST/UP (or VER)/additive ternary system and epoxy/curing agent /additive ternary systems during the cure was measured by differential scanning calorimetry (DSC) and Fourier transform infrared spectrometry (FTIR). Finally, based on the Takayanagi mechanical models, the glass transition temperature in each region of the cured samples for ST/UP (or VER)/additive ternary systems and epoxy/curing agent /additive ternary systems has been measured by the dynamic mechanical analysis (DMA).

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40

Tsai, Ming-Chou, and 蔡明洲. "Synthesis of nano-scale acrylic type of core-shell rubber tougheners with varied particle size and shell chemical composition and their phase characteristics in styrene/unsaturated polyester/additive ternary systems." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/q343pk.

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碩士
國立臺灣科技大學
化學工程系
94
Nano-scale acrylic type of core-shell rubbers (CSR), with varied particle size and shell chemical composition, as tougheners for unsaturated polyester resins (UP) have been synthesized by emulsion polymerizations, and styrene (ST)/UP/CSR ternary systems with different miscibility have been designed. By using Debye’s equation and the group contribution method, the dipole moments of UP and the shell component of the CSR can be calculated, which can then explain the phase characteristics of the ST/UP/CSR ternary system prior to the reaction at 25℃ and 110℃. Also, the compatibility of the ST/UP/CSR ternary system during the cure at 110℃ has been investigated by the cured sample morphology as observed by scanning electron microscopy (SEM).

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41

Huang, Hsin-Yao, and 黃新堯. "Effects of nano-scale core-shell rubber additives, inorganic silica /organic polymer core-shell particle, and montmorillonite clay on the cure kinetics, glass transition temperatures, volume shrinkage, mechanical properties and cured sample morphology for unsaturated polyester, vinyl ester, and epoxy resins." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/s6k57x.

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碩士
國立臺灣科技大學
化學工程系
100
The effects of four additives, including (1) nano- scale core-shell rubber additive,(2) inorganic silica gel/organic polymer core-shell particle, (3) organic montmorillonite clay, on the cure kinetics, glass transition temperatures, cured sample morphology, volume shrinkage characteristics and mechanical properties of the Styrene(St)/ Unsaturated polyester (or Vinyl ester resin)/ additives ternary systems and Epoxy/curing agent /additive ternary systems after the cure have been investigated. The experimental results have been explained by integrated measurements combining phase characteristic of the St/VER/additive ternary system and Epoxy/curing agent /additive ternary systems before the cure, final cure conversion, glass transition temperature, SAXS and WAXS analysis, cured sample morphology and Mechanical properties. Also the scattering intensity of vinyl ester resin (VER) and unsaturated polyester (UP) with different structure in dilute styrene solution was measured by the method of small angle X-ray scattering (SAXS), and the radius of gyration of VER and the UP molecule can then be calculated by using the Guinier law. The reaction kinetics for the ST/UP(or VER)/additive ternary system during the cure was measured by differential scanning calorimetry(DSC) and Fourier transform infrared spectrometry (FTIR). Finally, based on the Takayanagi mechanical models, the glass transition temperature in each region of the cured samples for ST/UP(or VER)/additive ternary system has been measured by dynamic mechanical analysis (DMA).

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42

Liu, Yi-Shan, and 劉伊珊. "Effects of nano- and submicron-scale core-shell rubber, inorganic/organic hybrid core-shell particle, and montmorillonite clay on cure kinetics, glass transition temperatures, volume shrinkage, mechanical properties and cured sample morphology for unsaturated polyester, vinyl ester, and epoxy resins." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/46798222045048248037.

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碩士
國立臺灣科技大學
化學工程系
101
The effects of four additives, including (1) nano- scale core-shell rubber additive,(2) inorganic silica gel/organic polymer core-shell particle, (3) organic montmorillonite clay, on the cure kinetics, glass transition temperatures, cured sample morphology, volume shrinkage characteristics and mechanical properties of the Styrene(St)/ Unsaturated polyester (or Vinyl ester resin)/ additives ternary systems and Epoxy/curing agent /additive ternary systems after the cure have been investigated. The experimental results have been explained by integrated measurements combining phase characteristic of the St/VER/additive ternary system and Epoxy/curing agent /additive ternary systems before the cure, final cure conversion, glass transition temperature, SAXS and WAXS analysis, cured sample morphology and Mechanical properties. Also the scattering intensity of vinyl ester resin (VER) and unsaturated polyester (UP) with different structure in dilute styrene solution was measured by the method of small angle X-ray scattering (SAXS), and the radius of gyration of VER and the UP molecule can then be calculated by using the Guinier law. The reaction kinetics for the ST/UP(or VER)/additive ternary system during the cure was measured by differential scanning calorimetry(DSC) and Fourier transform infrared spectrometry (FTIR). Finally, based on the Takayanagi mechanical models, the glass transition temperature in each region of the cured samples for ST/UP(or VER)/additive ternary system has been measured by dynamic mechanical analysis (DMA).

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43

yeu-shiun, shieh, and 謝宇軒. "Synthesis of nano-scale inorganic silica gel/organic polymer core-shell particle as additives by RAFT living free radical polymerizations for unsaturated polyester, viny ester, and epoxy resins." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/57494638192637782477.

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碩士
國立臺灣科技大學
化學工程系
97
Abstract Synthesis of inorganic/organic core-shell particle (CSP) as low-profile additives for unsaturated polyester resins by RAFT living free radical polymerizations has been studied in this work. Before the RAFT polymerization, the chain transfer agent with a chemical structure of Z-C(=S)-S-R was synthesized first. The synthesized chain transfer agent was then characterized by using FTIR、1H-NMR and DSC to confirm its structure. The chain transfer agent (CTA), namely, BSPA, was bonded onto the inorganic silica particles. The silica-supported BSPA was then used to mediate RAFT polymerization of methyl acrylate to produce homopolymer grafted silica, known as inorganic/organic core-shell particle (CSP). Moreover, the silica-supported PMA was then used to mediate RAFT polymerization of Butyl Acrylate to produce black copolymer grafted silica. It was found that the introduction of a free CTA in solution during polymerization could significantly improve the control on molecular weight and polydispersity of grafted polymers. Keyword ：reversible addition-fragmentation chain transfer(RAFT) ,chain transfer agent, inorganic/organic core-shell particle (CSP), unsaturated polyester resin (UP), low-profile additive (LPA).

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44

Jhan, Cheng-Ying, and 詹承穎. "Synthesis of nano-scale and submicron-scale polymeric core-shell rubber and reactive microgel particle as low-profile additives and tougheners for vinyl ester resins and epoxy resins by emulsion polymerizations." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6r3aq5.

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碩士
國立臺灣科技大學
化學工程系
107
Synthesis of nano-scale or submicron-scale general prepose core-shell rubber (gp-CSR) and nano-scale reactive microgel particles (RM) by conventional emulsion polymerization with or without surfactant as low-profile additives (LPA) and tougheners for unsaturated polyester resins (UP) and vinyl ester resin (VER) have been investigated. Two types of UP with different chemical structures, namely, MA-PG and MA-PA-PG, as well as epoxy resin (EPR) and vinyl ester resin (VER) with degree of polymerization (n) = 0.16, 2, and 5, have also been synthesized so that styrene (St) /VER /CSR ternary systems with different miscibility can be designed. For the synthesis of nano-scale gp-CSR, the core was made from PBA, the shell was made from poly(methyl acrylate)(PMA). For submicro-scale gp-CSR, the core was made from PBA, the shell was made from poly(methyl methacrylate) (PMMA). Futhermore, the shell of the CSR was modified by 5~15 mole percent of glycidyl methacrylate (GMA) as a comonomer to increase the molecular polarity and provide the specific functionality, such as epoxy group, for the shell of the CSR. For the synthesis nano-scale reaction microgel particles,two comonomers,including styrene (St) and unsaturated polyester (UP),were employed. Conventional emulsion polymerizations, which involved the addition of sodium dodecyl sulfate as a surfactant and 1-pentanol as a co-surfactant, along with the adjustment of PH value during the polymeriz -ation to facilitate a self-emulsifying copolymerization a simultaneous reaction of St and UP were carried out. As to the UP resine used as the monomer, it was made from maleic anhydride(MA) and 1,6-hexanediol (HD) by polycondensation in bulk at our laboratory. By conducting phase separation experiments and employing Debye’s equation, the dipole moments of UP, VER, EPR, the shell component of the CSR, and RM can be calculated, and the phase characteristics of the St/VER/CSR and St/VER/RM ternary systems have been elucidated. Finally, the volume shrinkage characteristics and mechanical properties of the St/VER (n=2)/CSR ternary system after cure have also been explored.

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45

TSENG, CHIEN-CHENG, and 曾建誠. "Synthesis of functionalized graphene oxide and functionalized exfoliated graphene nanoplatelets and effects of nano-scale and submicron-scale core-shell rubber additives, inorganic silica /organic polymer core-shell particle, functionalized graphene oxide, and functionalized exfoliated graphene nanoplatelet on the volume shrinkage, mechanical properties and cured sample morphology for unsaturated polyester and vinyl ester resins." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/14841570663378769252.

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碩士
國立臺灣科技大學
化學工程系
103
The effects of the submicron-scale core–shell rubber (CSR), nano-scale silane-grafted silica nanoparticles (SNP) and thermally reduced graphene oxide as special additives on volume shrinkage characteristics and mechanical properties of the styrene (St)/vinyl ester resin(VER)/special additive ternary systems cured at 120 ℃ and post cured at 150 ℃have been investigated. The SNP with a diameter of 15 nm was synthesized by size-controllable hydrolysis of elemental silicon, followed by the surface treatment of 3-methacryloxypropyltrimethoxysilane (γ-MPS) to obtain the MPS-silica. The CSRs were synthesized by two-stage soapless emulsion polymerizations, where the soft core was made from rubbery poly(n-butyl acrylate), and the hard shell was made from 85 mole% of methyl methacrylate, 15mol% glycidyl methacrylate, and 1mole% of ethylene glycol dimethacrylate as the crosslinking agent. The experimental results are explained by an integrated approach of measurements of the static phase characteristics of a St/VER/special additive system, the cured sample morphology with SEM, TEM, and mechanical properties.

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46

Zhang, Li. "Thermally-responsive core-shell particles." 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3270676.

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47

Yaung, Chang-Rui, and 楊昌叡. "Synthesis of nano-scale and submicron-scale polymeric core-shell rubber and reactive microgel particle as low-profile additives and tougheners for unsaturated polyester and vinyl ester resins by conventional emulsion polymerizations." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/vrabgk.

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Abstract:

碩士
國立臺灣科技大學
化學工程系
105
Synthesis of nano-scale or submicron-scale general prepose core-shell rubber (gp-CSR) and nano-scale reactive microgel particles (RM) by conventional emulsion polymerization with or without surfactant as low-profile additives (LPA) and tougheners for unsaturated polyester resins (UP) and vinyl ester resin (VER) have been investigated. Two types of UP with different chemical structures, namely, MA-PG and MA-PA-PG, as well as epoxy resin (EPR) and vinyl ester resin (VER) with degree of polymerization (n) = 0.16, 2, and 5, have also been synthesized so that styrene (St) /VER /CSR ternary systems with different miscibility can be designed. For the synthesis of nano-scale gp-CSR, the core was made from PBA, the shell was made from poly(methyl acrylate)(PMA). For submicro-scale gp-CSR, the core was made from PBA, the shell was made from poly(methyl methacrylate) (PMMA). Futhermore, the shell of the CSR was modified by 5~15 mole percent of glycidyl methacrylate (GMA) as a comonomer to increase the molecular polarity and provide the specific functionality, such as epoxy group, for the shell of the CSR. For the synthesis nano-scale reaction microgel particles,two comonomers,including styrene (St) and unsaturated polyester (UP),were employed. Conventional emulsion polymerizations, which involved the addition of sodium dodecyl sulfate as a surfactant and 1-pentanol as a co-surfactant, along with the adjustment of PH value during the polymerization to facilitate a self-emulsifying copolymerization a simultaneous reaction of St and UP were carried out. By varying the molar ratio of styrene to UP C=C bonds (MR), reactive microgels with diameters ranging from 30nm to 100nm have been synthesized. As to the UP resine used as the monomer, it was made from maleic anhydride(MA) and 1,6-hexanediol(HD) by polycondensation in bulk at our laboratory. By conducting phase separation experiments and employing Debye’s equation, the dipole moments of UP, VER, EPR, the shell component of the CSR, and RM can be calculated, and the phase characteristics of the St/VER/CSR and St/VER/RM ternary systems have been elucidated. Finally, the volume shrinkage characteristics and mechanical properties of the St/VER (n=2)/CSR ternary system after cure have also been explored.

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48

Liou, Wan-Da, and 廖萬達. "Effects of reactive microgel particle type of low-profile additives, nano-scale core-shell rubber tougheners, and montmorillonite clay on the volume shrinkage, internal pigmentability, and cured sample morphology forstyrene/unsaturated polyester/additive." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/45655348801677122493.

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碩士
國立臺灣科技大學
化學工程系
93
The effect of four series of additives, including(1)poly(vinyl acetate) (PVAc), (2)polycaprolactone(PCL) low-profile additives, (3)reactive microgel particle, (4) montmorillonite clay, on the microvoid formation, morphology, volume shrinkage characteristics,internal pigmentability and mechanical properties for the styrene/unsaturated polyester/additive ternary systems after the cure were investigated. The experimental results have been explained by phase characteristic of the styrene/ unsaturated poly- ester /additive ternary system before tht cure, cured sample morph- ology and volume fraction of microvoid generated during the cure.

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49

Lin, Yi-Tsung, and 林誼聰. "Effects of reactive microgel particle type of low-profile additives, nano-scale core-shell rubber tougheners, and montmorillonite clay on the cure kinetics and glass transition temperatures for styrene/unsaturated polyester/additive ternary systems." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/92601828848729867556.

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碩士
國立臺灣科技大學
化學工程系
93
The effects of reactive microgel particle type of low-profile additives, the effects of core structure and addition of nano-scale core-shell rubber tougheners, and the effects of addition of montmorillonite clay on the cure kinetics and glass transition temperatures for styrene/unsaturated polyester/additive ternary systems. In addition, The effects of the miscibility of styrene/unsaturated polyester/additive ternary systems on DSC reaction rate profile and the cured sample morphology also were investigated.Finally, base on the Takayanagi mechanical models, the glass transition temperature in each phase region of cured saples has been identified by the method of thermally stimulated currents analyser.

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50

Mckenzie, A., Richard Hoskins, Thomas Swift, Colin A. Grant, and Stephen Rimmer. "Core (Polystyrene)−Shell [Poly(glycerol monomethacrylate)] Particles." 2017. http://hdl.handle.net/10454/11485.

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Yes
A set of water-swollen core−shell particles was synthesized by emulsion polymerization of a 1,3-dioxolane functional monomer in water. After removal of the 1,3- dioxolane group, the particles’ shells were shown to swell in aqueous media. Upon hydrolysis, the particles increased in size from around 70 to 100−130 nm. A bicinchoninic acid assay and ζ-potential measurements were used to investigate the adsorption of lysozyme, albumin, or fibrinogen. Each of the core−shell particles adsorbed significantly less protein than the noncoated core (polystyrene) particles. Differences were observed as both the amount of difunctional, cross-linking monomer and the amount of shell monomer in the feed were changed. The core−shell particles were shown to be resistant to protein adsorption, and the degree to which the three proteins adsorbed was dependent on the formulation of the shell.
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Dissertations / Theses on the topic 'Core-Shell Particle'

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