Abstract: The aim of this research is to fabricate thin-film composite (TFC) membranes using a synthetic derivative of plant-based phenols, as a non-toxic building block for interfacial polymerization. Classical interfacially polymerized composite membranes are heavily integrated in reverse osmosis and nanofiltration applications for water and wastewater treatment and most recently for chemical and pharmaceutical industries. Implementing sustainable practices in membrane fabrication by exploiting greener alternatives to conventional chemicals can directly reduce hazardous waste and ultimately lower the global energy and environmental burdens. In this study, allyl gallate was chosen as a monomer to form selective thin films by the interfacial reaction with trimesoyl chloride on top of an asymmetrically porous polyacrylonitrile support. The advantage of the unreacted allyl groups is that they can be in the future used as post-functionalization sites. The highly volatile organic phase solvents were additionally replaced by an isoparaffinic fluid, commercially known as Isopar G. The chemical composition and morphology of the membrane was evaluated using solid-state 13C NMR, FTIR, and SEM. The optimized membrane resulted in a permeance of 12±2 and 48±14 L m-2 h-1 bar-1 for respectively pure water and methanol with a rejection in the nanofiltration range.

In the last decades, there has been a trend towards bio-inspired approaches for the formation of nanocoatings as well as to accomplish energy-intensive industrial separations in a more sustainable fashion. Solvent Resistant Nanofiltration (SRNF) is a pressure driven technology where the operation conditions are moderate and additional waste streams are minimized, making this a favorable energy efficient approach for challenging molecular separations such as purification of active pharmaceutical ingredients, production of specialty chemicals and in the petrochemical industry just to mention a few examples, where this technology can be currently applied. The overall performance of SRNF membranes is determined by solute/solvent interactions with the membrane top layer. Therefore, the modification of the membrane surface becomes crucial to obtain high-performance SRNF membranes, as well as exploring novel and green approaches to improve the separation properties of SRNF membranes, without sacrificing their permeation properties. One alternative for the fabrication of the thin-films in SRNF membranes proposed in this work is the use of biopolyphenolic molecules. Among the many classes of phenolic biomolecules, plant phenols are capable of binding and cross-linking due to their strong interfacial activity. Here, the successful optimization of the interfacial polymerization reaction for the manufacture of SRNF membranes is demonstrated by replacing the common toxic amines used for this method with natural occurring bio-polyphenols such as dopamine, tannic acid, morin hydrate and catechin. These bio-polyphenols can be found in mussels, date fruits, guava fruits and green tea respectively and they were used to form a selective thin film on top of a crosslinked polyacrylonitrile or a cellulose support. These membranes have shown an exceptional performance and resistance towards harsh solvent environments. Due to the incorporation of natural compounds for the manufacture, they provide a cost-effective alternative for industrial separations due to the ease of chemical modification and preparation, which is potentially easy to scale up at low cost taking advantage of the natural compounds for their manufacture.

Made available in DSpace on 2014-12-17T15:01:33Z (GMT). No. of bitstreams: 1 JulianaLM_DISSERT.pdf: 3337263 bytes, checksum: f1607b1c73a3ec40c4bd82f3a0b43c14 (MD5) Previous issue date: 2013-08-08 / The industries of food, medicine and cosmetic apply microencapsulation for many reasons, among them, stabilize the active, control the release of encapsulated and separate incompatible components of the formulation. In this context, microencapsulation techniques have been used in the food industry to provide stable liquid and solid ingredients. Anthocyanins have high antioxidant potential, but they are photodegradable. The challenges are therefore directed to the research for techniques that could make this potential remaining active and bioavailable and could be used as a vehicle for the delivery release of bioactive and micronutrients in appropriate conditions and levels. This work has as main objective to propose a method to encapsulate the anthocyanins in the extract of mountain apple using the interfacial polymerization technique. As well as to define the ideal conditions of temperature and agitation system for this procedure. The microparticles were characterized for size, morphology, active distribution, surface charge, degradation, composition and stability. The results, like particle diameter of 5.94 μm and Zeta potential of 7.03 mV, showed that the technique used to obtain these microparticles was satisfactory and has potential for application in cosmetics and food / As ind?strias de alimentos, medicamentos e cosm?ticos aplicam a microencapsula??o por diversas raz?es, dentre elas, estabilizar o ativo, controlar a libera??o do encapsulado e separar componentes incompat?veis da formula??o. Dentro deste contexto, as t?cnicas de microencapsula??o t?m sido usadas na ind?stria de alimentos para fornecer ingredientes l?quidos e s?lidos est?veis. As antocianinas possuem alto potencial antioxidante, entretanto s?o fotodegrad?veis. Os desafios s?o portanto, direcionados ? busca de t?cnicas que fa?am com que este potencial permane?a ativo e biodispon?vel para que possa ser usado como ve?culo para a libera??o de bioativos e micronutrientes, em condi??es e n?veis adequados. Este trabalho tem como objetivo principal propor uma t?cnica para encapsular as antocianinas presentes no extrato do jambo vermelho utilizando a t?cnica de polimeriza??o interfacial. Foram definidas as condi??es ideais de temperatura e agita??o do sistema para o referido processo. As micropart?culas obtidas foram caracterizadas quanto ao tamanho, morfologia, distribui??o do ativo, carga superficial, degrada??o, composi??o e estabilidade. Os resultados obtidos, tal como di?metro de part?cula de 5,94 μm e potencial Zeta de +7,03 mV, mostraram que a t?cnica utilizada para obten??o destas micropart?culas foi satisfat?ria e possui potencial para aplica??o na ind?stria de cosm?ticos e alimentos

L’embolisation vasculaire est un traitement peu invasif utilisé pour éliminer ou interrompre de façon sélective les apports vasculaires à des régions spécifiques du corps. Une technique consiste en l’introduction d’un microcathéter dans le vaisseau sanguin cible et à administrer un agent embolique qui réagit au contact du sang. Les colles emboliques à base de cyanoacrylate sont les principaux agents liquides utilisés pour l’embolisation à cause de leur faible viscosité, leur bonne capacité de pénétration et leur faible toxicité tissulaire. Pour permettre sa détection après injection, la colle est mélangée à un agent de contraste radio-opaque telle que l’huile iodée Lipiodol®. Bien que la technique soit couramment utilisée, il existe peu de données sur la dynamique du processus d’injection au sein de flux sanguins complexes ou sur la cinétique de polymérisation du mélange colle-Lipiodol. Par conséquent, une occlusion sans danger est difficile à réaliser, même entre les mains de radiologues expérimentés. Le principal objectif de la thèse est d’étudier de façon quantitative les propriétés physiques et la cinétique de polymérisation des colles cyanoacrylates mélangées au Lipiodol dans différentes proportions. Nous avons conçu un nouveau dispositif expérimental pour caractériser le processus de polymérisation d’un mélange colle/Lipiodol en contact avec une solution ionique ou protéinée. Les résultats montrent un processus de polymérisation rapide à l’interface entre la colle et le substrat, suivi par la proagation d’un front de polymérisation dans le volume de préparation de colle. Les constantes de temps des processus dépendent des compositions de la solution et du mélange de colle. Un autre objectif est d’analyser le processus d’embolisation dynamique. Un modèle in vitro du processus d’injection est utilisé pour étudier en premier lieu la formation de goutte entre deux flux immiscibles et qui ne réagissent pas entre eux. L’injection d’une préparation de colle dans une solution ionique en écoulement est ensuite réalisée pour montrer l’influence conjointe de la polymérisation et de l’hydrodynamique. C’est la première fois qu’une telle caractérisation exhaustive de colles emboliques à base de cyanoacrylate est obtenue. Les résultats peuvent apporter des informations cruciales aux radiologues interventionnels, ce qui les aidera à comprendre et contrôler le comportement de la colle après injection afin d’accomplir une oblitération permanente des vaisseaux en toute sécurité. / Vascular embolization is a minimally invasive treatment used to selectively eliminate or stop the vascular supply to specific body areas. One technique consists of navigating a microcatheter into the targeted blood vessel and injecting an embolic agent which reacts in contact with blood. Cyanoacrylate-based embolic glues are the main liquid adhesives used for vascular embolization owing to their low viscosity, good penetration ability and low tissue toxicity. To enable its detection once injected, the glue is mixed with a radio-opaque contrast agent such as the Lipiodol iodized oil. Although the technique is commonly used, there is very little information on the dynamics of the injection process in complex blood flows or on the polymerization kinetics of the glue-Lipiodol mixture. Consequently, safe occlusion is difficult to achieve, even in the hands of experienced radiologists. The main objective of the thesis is to quantitatively investigate the physical properties and polymerization kinetics of cyanoacrylate glues mixed with Lipiodol in different proportions. We have designed a new experimental setup to characterize the polymerization process of a glue/Lipiodol mixture on contact with an ionic or proteinaceous solution. We find that there is a fast polymerization process at the interface between the glue and the substrate, followed by the propagation of a polymerization front in the glue mixture volume. The time constants of the processes depend on the solution and glue mixture compositions. Another objective is to analyze the dynamic embolization process. An in vitro model of the injection process is used to first investigate the drop formation between two non-reacting immiscible flows. The injection of a glue mixture into a flowing ionic solution is then performed to show the joint influence of polymerization and hydrodynamics. It is the first time that such comprehensive characterization of cyanoacrylate-based embolic glues is acquired. The results can provide crucial information to interventional radiologists, that will help them understand and control the glue behavior after injection to achieve a safe and permanent obliteration of the vessels.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19012号 / 工博第4054号 / 新制||工||1624(附属図書館) / 31963 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 赤木 和夫, 教授 辻井 敬亘, 教授 古賀 毅 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

L'objectif de ce travail de recherche est l'étude du transport des ions et des molécules d'eau à travers de membranes bicouche lipidique et des membranes polymériques. Dans une première partie, ce transport a été réalisé à travers des systèmes synthétiques auto-organisés, dont la sélectivité est en étroite relation avec le type d'architecture supramoléculaire formée grâce à des liaisons faibles. Le but est d'obtenir des systèmes qui peuvent imiter les fonctions de transport des protéines membranaires. Ce mimétisme fonctionnel est obtenu par l'auto-assemblage de molécules organiques contenant le cycle imidazole et la fonction urée, qui peuvent s'auto-assembler et créer des voies sélectives de transport des ions. Pour créer l'équivalent de la membrane cellulaire, nous avons utilisé des vésicules lipidiques unilamellaires. Ensuite, nous avons déterminé une relation entre l'activité des composés et leur structure. Pour ce faire, le transport des ions est étudié à l'aide d'une méthode de spectroscopie de fluorescence, et le transport d'eau par diffusion dynamique de la lumière utilisant la technique de « stopped flow ». Le but de la deuxième partie est la fabrication et la caractérisation des nouvelles membranes composites sous forme de couches minces, qui permettraient un bon compromis entre le flux d'eau et le rejet de sel. Dans ce cadre, la synthèse d'une série d'hydrazides en tant que précurseurs moléculaires a été réalisée, pour remplacer la métaphenylène diamine (MPD) classiquement utilisée. Ici aussi les liaisons hydrogène jouent un rôle important, car le principe de la séparation repose sur la création d'une organisation interne hautement réticulée. Les polymères synthétisés par polymérisation interfaciale ont été caractérisés par des méthodes de spectroscopie infrarouge, analyses thermogravimétriques et diffraction des rayons X. Les membranes composites ont été caractérisées par microscopie électronique à balayage, microscopie à force atomique et mesures d'angle de contact. Les performances membranaires ont été testées en filtration frontale d'eau et de solutions salines. / The aim of this work is the study of ion and water transport either across bilayer membranes or polymeric membranes used for reverse osmosis. In the first part, this transport through self-assembled synthetic systems was studied; the transport selectivity is in strong relation with the supramolecular structure, formed by weak intra and intermolecular bonds. Ion transport is studied by fluorescence spectroscopy and water transport is studied by light scattering using “stopped flow” technique. The objective is to obtain systems that could imitate transport functions of biomolecules as transmembrane proteins. This functional mimicry is achieved through self-assembly of organic molecules containing imidazole cycle and urea function that can self-assembly and form selective pathways for ion transport. To create the equivalent of the cell membrane, we used unilamellar lipid vesicles. Then, we determined a structure - transport activity relationship for a series of synthesized compounds. For the second part of this work we described the fabrication and the characterization of new thin film composite membranes for water desalination that can present a good balance between permeability and salt rejection. A series of hydrazides as molecular precursors was synthesized in order to replace the metaphenylene diamine (MPD), classically used. Again, hydrogen bonds play an important role, because the rejection is due to a high cross-linking. The polymers synthesized by interfacial polymerization were characterized by infrared spectroscopy, thermogravimetric analysis, and X-Ray diffraction. The membrane films were characterized by scanning electron microscopy, atomic force microscopy and contact angle measurements. Membrane performances were then tested in cross-flow filtration of water and saline solutions.