Thèses sur le sujet « Polymer aqueous solution »
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Suzuki, Shinya. « Rheological Properties of Telechelic Associative Polymer in Aqueous Solution ». 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/200500.
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Sidhu, Jagraj. « Equilibrium and structural studies of polymer / surfactant assemblies in aqueous solution ». Thesis, University of Salford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420463.
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Piluso, Pierre. « Développement de nouvelles formulations à base de polymères fonctionnels pour la mise au point de papiers techniques à propriétés spécifiques ». Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1090.
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Cette thèse a consisté à étudier la réaction d'acétalisation en milieu aqueux de l'alcool polyvinylique (PVA) par un aldéhyde non hydrosoluble à longue chaîne alkyle (10-14 carbones) porteur d'une fonctionnalité vinyle en bout de chaîne, pour des conditions spécifiques : concentration en polymère de 8 % massique et degrés d'acétalisation (DA) faibles (<5,6 mol%). L'objectif de cette réaction de greffage est l'obtention de films obtenus par évaporation de solvant ayant une fonctionnalité de surface. L'influence des paramètres de réaction (concentration en réactifs, pH) sur la cinétique a été étudiée sur un composé modèle, le pentane-2,4-diol, puis sur le PVA. Une méthode de dosage par RMN 1H a permis d'identifier et de quantifier les composés en présence dans le milieu de réaction.Un objectif de la thèse a été de maximiser le DA en conservant une viscosité adéquate pour un procédé d'enduction. Pour cela, l'impact du greffage par le 10-undécénal sur l'organisation et les propriétés rhéologiques des solutions d'un PVA référence à 8 % massique a été étudié en premier lieu jusqu'à un DA de 1,85 mol%. Une méthode de quantification de faibles quantités de groupements vinyle en surface des films de PVA acétalisé a permis d'étudier leur orientation en surface pour une gamme de DA de 0 à 1,48 mol%.L'influence de la masse molaire du PVA et de la longueur de chaîne alkyle de l'aldéhyde sur la cinétique d'acétalisation et son impact sur la viscosité des solutions ont également été étudiés. L'utilisation d'un PVA de masse molaire plus faible apparait être un moyen efficace de maximiser le DA tout en conservant une viscosité acceptable pour un procédé d'enductionThis PhD work dealt with the study of the acetalization reaction of polyvinyl alcohol (PVA) in aqueous medium by non-water soluble aldehydes bearing long alkyl chains and a vinyl end group such as 10-undecenal in specific conditions: in 8 wt% concentrated PVA solutions and with low acetalization degree (AD) from 0.33 mol% to 5.6 mol%. The main purpose of this grafting reaction is to obtain an activated surface on water casted polymer films. First, the impact of reactants concentrations, pH and reaction atmosphere on the acetalization kinetics was studied with a model compound first, pentane-2,4-diol, then with PVA. A new 1H NMR titration method allowed to carry out in situ quantification of the amount of reactant and of grafted aldehyde.On main objectives of this work was to obtain the highest DA while keeping PVA solutions viscosity as low as possible to keep a sufficiently low solution viscosity for a solvent cast process. The impact of AD by 10-undecenal on PVA solution organization and on the rheological properties of 8 wt% PVA aqueous solutions were investigated first until 1.85 mol% AD. A surface vinyl groups quantification method was developed through chemical labeling of the vinyl groups at the surface of solvent casted PVA films and 1H NMR titration of the labels. This method allowed the study of vinyl groups orientation toward the surface of acetalized PVA films until 1.48 mol% AD.The influence of PVA molar mass and of aldehyde alkyl chain length on acetalization kinetics and solutions viscosity was also studied. The use of a low molar mass polymer appeared to be an efficient way to obtain highly modified films while keeping a low 8 wt% acetalized PVA solution viscosity
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Lower, Russell John. « The reactions of free and polymer-bound iron(III) porphyrins with tertiary-butyl hydroperoxide in aqueous solution ». Thesis, University of York, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292604.
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Orpiszak, Martin. « Oxidation of cellulose to favour its dissolution in alkaline aqueous solution before regeneration into textile yarn ». Thesis, KTH, Kemiteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-296556.
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Detta examensarbete är en del av CelluFil-projektet och syftar till att optimera förhållandena för upplösning av cellulosa i vattenlösning av natriumhydroxid följd av regenering i form av ett garn. Tidigare arbeten har visa tatt cellulosa kan lösas i vattenlösning vid -10°C, men sådana förhållanden är inte tillämpliga i industriell skala. Målet med detta projekt är att arbeta vid rumstemperatur. För detta kommer karboxylgrupper att införas i cellulosakedjorna för att öka cellulosans lighet i ett alkaliskt vattenbaserat medium. Därefter kommer cellulosan att fällas ut igen i en sur lösning. Natriumperjodat gör det möjligt att oxidera alkoholgrupperna i cellulosakedjan på C2- och C3- positionerna genom att öppna glukosenheterna för att skapa två karbonylfunktioner (aldehyde) som sedan lätt kan oxideras till karboxylgrupper med överoxidering med natriumklorit. Den första delen av rapporten är tillägnad litteraturöversikten om ämnet med focus på natriumperjodat oxidation. Därefter föreslås ett allmänt protokoll från natriumperjodat oxidation till regenering av cellulosa till garn i en svavelsyralösning. Flera förhållanden för natriumperjodat oxidationen testas vid olika temperaturer, med eller utan metallsalter och med olika oxidationsdoser. Upplösningsutbytet är direkt kopplat till karboxylinnehållet infört i cellulosakedjorna. Periodatoxidationen leder också till minskningen av polymerisationsgraden men cellulosas DPv förblir tillräckligt hög med det riktade COOH-innehållet och för textilapplikationer. Den möjliga produktionen av hydroxylradikaler under natriumperjodat oxidationen har undersökts med EPR/Spin-trapping. Endast försök gjorda med UV-strålning visade OH°. Således förklaras fortfarande inte depolymerisationen av cellulosa under perjodat oxidation framställd under mörka förhållanden. Eftersom, konsumtion av natriumperjodat är låg under oxidationen är dess återvinning en nyckelfråga för en industriell applikation. Det har visat sig att oxidationsfiltraten kan återanvändas flera gånger före total konsumtion av periodat. Kvaliteten på celluloser oxiderade med återvunna filtrat, särskilt deras upplösningsförmåga, bör kontrolleras.This master thesis is part of the Cellufil Project and aims to optimize the conditions for dissolving cellulose in aqueous sodium hydroxide solution followed by regeneration it in the form of a yarn. Previous works have shown that cellulose could be dissolved in soda at -10°C, but such conditions are not applicable at industrial scale. The objective of the present project is to work at room temperature. For that, carboxyl groups will be introduced in the cellulose chains in order to increase cellulose solubility in an alkaline aqueous medium, after this it is reprecipitated it in acidic solutions. Periodate makes it possible to oxidize the alcohol groups of cellulose on C2 and C3 positions by opening the glucose units to create two carbonyls functions (aldehyde) which can then be easily oxidized into carboxylic groups with overoxidation using sodium chlorite. A first part of the report is dedicated to the literature review on the subject, focusing on periodate oxidation. Then, a general protocol is proposed from the periodate oxidation to the regeneration of cellulose into yarn in sulfuric acid solutions. Several conditions for the periodate oxidation are tested, at different temperatures, with or without metal salts and with different oxidant dosages. The dissolution yield is directly linked to the carboxyl content introduced in the cellulose chains. The periodate oxidation also leads to the decrease of the cellulose degree of polymerization but cellulose DPv still remains sufficiently high in the case of the targeted COOH contents and for textile applications. The possible production of hydroxyl radicals during the periodate oxidation has been investigated by EPR/Spin-trapping. Only trials made with UV radiations showed OH°. Thus, cellulose depolymerization during periodate oxidation made in dark conditions is still not explained. Because the periodate consumption is low during the oxidation, its recycling is a key issue for an industrial application. It has been shown that the oxidation filtrates could be reused several times before total oxidant consumption. The quality of celluloses oxidized with recycled filtrates, especially their dissolving ability, should be checked.
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Roure, Isabelle. « Rhéologie et dimensions des chaines du hyaluronane en solution ». Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10227.
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Dans ce travail, nous avons cherche a relier le comportement rheologique des solutions de hyaluronane (ha) et de son derive reticule le hylane, aux dimensions des chaines. Dans une premiere partie nous avons etudie l'influence de la force ionique sur la viscosite des solutions et sur la separation en masse molaire par chromatographie d'exclusion sterique (sec). Nous montrons que la contribution du ha a la force ionique correspond a celle d'un electrolyte simple. L'obtention a de faibles forces ioniques d'un maximum dans la courbe viscosite reduite en fonction de la concentration en polymere a ete interpretee a partir des theories des polyelectrolytes. Ceci nous a permis de mieux comprendre le role des interactions electrostatiques. L'utilisation de la sec couplee a trois detecteurs en fonction de la force ionique de l'eluant nous a permis de definir l'influence de la force ionique sur la separation, de valider la loi d'etalonnage universelle. La comparaison des variations experimentales de et rg en fonction de la masse obtenues par sec avec celles obtenues theoriquement permet de determiner la longueur de persistance intrinseque du ha egale a 70a. Dans une deuxieme partie, nous avons montre que la variation de la viscosite specifique des solutions de ha suivait une loi en c dans le regime dilue et en cm dans le regime semi-dilue. A partir de la variation des viscosites avec la temperature nous avons caracterise trois domaines dans le regime semi-dilue. Le domaine intermediaire est caracterise par une diminution de l'influence de la temperature sur la viscosite. Nous avons attribue cette diminution (qui est fonction du produit cm) a une augmentation de la rigidite des chaines de ha. Enfin, nous montrons dans la derniere partie que le comportement rheologique du hylane en solution correspondrait, s'il etait possible de le synthetiser, a celui d'un ha de tres forte masse molaire, conditions qui favorisent particulierement les proprietes viscoelastiques.
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Wehbe, Elsy. « Magnetohydrodynamic of a non-newtonien fluid ». Electronic Thesis or Diss., Pau, 2023. https://theses.hal.science/tel-04421152.
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La magnétohydrodynamique (MHD) est la discipline qui étudie le comportement des fluides conducteurs d'électricité lorsque leur mouvement est couplé au champ électromagnétique. Ici, nous étudions dans un domaine possiblement multi connexe dans 2D, l'existence des solutions pour un problème MHD couplant une équation de solution aqueuse de polymères avec l'équation de Maxwell de l'électromagnétisme. Pour résoudre notre problème, nous avons besoin de certaines estimations liées au problème associé de Stokes. L'une des difficultés réside dans la géométrie du domaine et le terme non linéaire d'ordre trois $(u cdot nabla)(u-alpha Delta u)$. D'autre part, il est démontré qu'il existe une régularité supplémentaire dans $W^{2,p}(O)$ pour le champ magnétiqueMagnetohydrodynamics (MHD) is the discipline studying the behavior of conductive fluids of electricity when their movement is coupled to the electromagnetic field. Here we study in $Omega$, a possibly multi-connected two-dimensional domain, the existence of solutions for an MHD coupling an equation of polymer aqueous solution with Maxwell equation of electromagnetic. To solve our problem we need some estimations related to the Stokes-associated problem. One of the difficulties is the geometry of the domain and the nonlinear term of third order $(u cdot nabla)(u-alpha Delta u)$. On the other hand, it is shown an additional regularity in $W^{2,p}(O)$ for the magnetic field
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Bataille, Isabelle. « Propriétés associatives en solution aqueuse de dérivés alkylés de carboxyméthylpullulanes ». Rouen, 1998. http://www.theses.fr/1998ROUES013.
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Le pullulane est un polysaccharide de fermentation caractérisé par un squelette neutre, hydrosoluble et flexible. Des dérivés anioniques et amphiphiles du pullulane ont été préparés par carboxyméthylation (0,76
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Anim-Danso, Emmanuel. « Understanding the structure of water, ice, and aqueous solutions next to solid surfaces ». University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1441318237.
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Boutebba, Abdelkader. « Propriétés du succinoglycane : transition conformationnelle et gélification en milieu aqueux ». Université Joseph Fourier (Grenoble ; 1971-2015), 1998. http://www.theses.fr/1998GRE10136.
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Le succinoglycane est un polysaccharide charge d'origine bacterienne qui presente en solution aqueuse une transition conformationnelle ordre-desordre. La premiere partie de ce travail a porte sur l'etude de cette transition. Nous avons precise, a partir des proprietes polyelectrolytes, que la conformation ordonnee etait une simple helice. Nous avons montre le role particulier des substituants charges succinate sur la stabilite de cette helice. Quelle que soit la quantite de groupements succinate presents, l'enthalpie de transition par unite repetitive reste constante, ce qui montre que la contribution non polyelectrolyte a cette enthalpie est preponderante. Dans la deuxieme partie, nous avons cherche a comprendre l'origine et le mecanisme de la formation d'associations interchaines. Ces associations peuvent etre deja presentes dans la conformation native du polymere. Elles sont supprimees lors d'un premier passage au-dela de la temperature conformationnelle lorsque le parametre de recouvrement c est inferieur a 8. Pour des valeurs superieures, de nouvelles associations se forment de facon reversible lors de la transition desordre-ordre qui conduisent a la formation d'un gel faible et elastique. Une cinetique lente de stabilisation de ces associations est observee. Elles deviennent alors progressivement stables au-dela de tm mais semblent impliquer moins de 5% des segments des chaines. Dans la troisieme partie, les proprietes rheologiques des solutions ont ete etudiees. Nous avons retrouve, en absence d'associations, le comportement normal de solutions de polymeres et mis en evidence, dans certaines conditions, la formation d'associations intermoleculaires. L'influence de la temperature a ete reliee a la rigidite des chaines et a l'aptitude de ce polymere a former des associations interchaines.
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Catonné, Jean-Claude. « Contribution à l'étude du défaut de sélectivité présenté par les membranes échangeuses d'anions, dans le cadre de leurs applications au traitement électrochimique de régénération des solutions aqueuses d'acides minéraux ». Paris 6, 1986. http://www.theses.fr/1986PA066030.
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Essai d'identification de l'origine de la "fuite h+" et de celle des différentes sources susceptibles d'alimenter le mouvement d'eau au sein des membranes échangeuses d'anions, selon que le matériau est fortement ou non "élusterisé", puis d'établissement de l'existence d'une corrélation étroite entre l'intensité de fuite protonique et celle de la perméabilité osmotique des membranes (ainsi que le laisse prévoir la théorie de Gierke dans le cas des membranes échangeuses de cations). Et enfin, évaluation du rôle du champ électrique, ainsi que celui de la composition de l'électrolyte sur les résultats.
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Ma, Yunwei. « A Thermal Switch from Thermoresponsive Polymer Aqueous Solutions ». Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/86837.
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Thermal switch is very important in today’s world and it has varies of applications including heat dissipation and engine efficiency improving. The commercial thermal switch based on mechanical design is very slow and the structure is too complicated to make them smaller. To enable fast thermal switch as well as to make thermal switch more compact, I try to use second-order phase transition material to enable our thermal switch. Noticing the transition properties of thermoresponsive polymer for drug delivery, its potential in thermal switch can be expected. I used Poly(N-isopropylacrylamide) (PNIPAM) as an example to show the abrupt thermal conductivity change of thermoresponsive polymer solutions below and above their phase transition temperature. A novel technique, transition grating method, is used to measure the thermal conductivity. The ratio of thermal switch up to 1.15 in transparent PNIPAM solutions after the transition is observed. This work will demonstrate the new design of using second-order phase transition material to enable fast and efficient thermal switch.Master of Science
Controllable thermal conductivity (thermal switching) is very important to thermal management area and useful in a wide area of applications. Nowadays, mechanical thermal conductivity controller device suffers from large scale and slow transition speeds. To solve these problems, I tired the phase transition thermoresponsive polymers to create quick thermal switching because the thermal conductivity will change with the phase. Thermoresponsive polymers show sharp phase changes upon small changes in temperature. Such polymers are already widely used in biomedical-like applications, the thermal switch applications are not well-studied. In this work, I tested Poly(N-isopropylacrylamide) (the abbreviation is PNIPAM) as an example to show the quick thermal conductivity changing ability of thermoresponsive polymer when the transition was happened .I used a novel approach, called the TTG, transient thermal grating. It has easy setup and high sensitivity. The thermal conductivity switching ratio as high as 1.15 in transparent PNIPAM solutions after transition is observed. This work will give new opportunities to control thermal switches using the phase change of thermoresponsive material or abrupt other phase change material in general.
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Oktar, Doganay Ceren. « Separation Of Chromate And Borate Anions By Polymer Enhanced Ultrafiltration From Aqueous Solutions Employing Specifically Tailored Polymers ». Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12609178/index.pdf.
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In this study two polychelatogens for borate and a polyelectrolyte for chromate retention (R) were designed for investigating the effect of pH and loading (g metal /g polymer) on the separation performances of the synthesized polymers using continuous polymer enhanced ultrafiltration.
Increase in pH increased the retention of borate for all of the synthesized polymers. Decrease in the loading resulted in an enhancement in boron retention with PNSM and PNSL. When COP was utilized, retentions remained almost constant after a certain loading, probably due to possible adverse effects of high polymer concentrations on polymer conformation in aqueous solutions.
Decrease in loading caused an increase in the retention of chromate until a loading of 0.01. After that a slight decrease was observed. Maximum Cr (VI) retention was obtained as 0.70 for a loading of 0.01 and a pH of 4. Effect of crowding on Cr(VI) retention was also investigated. It was observed that retention does not only depend on the loading but also on the concentrations of both Cr (VI) and PDAM. Effect of the presence of competing anions such as chloride and sulfate on the retention of chromate was investigated to see the effect of competing anion charge to the selectivity of the synthesized polyelectrolyte. Addition of both anions decreased the retention of Cr(VI) . Divalent sulfate decreased the retention more than monovalent chloride indicating that charge of the anion may be the predominant variable in the retention of chromate using PDAM.
Finally, dynamic and static light scattering measurements were performed to investigate the conformational changes in the structure of the synthesized polymers at different pH values as well as in the presence of boron in the solution.
In this study, it is shown that PEUF can be successfully applied to for boron and Cr (VI) retention with the synthesized polymers. Satisfactory retention values were obtained both for boron and Cr (VI). Even if the retention of Cr (VI) decreased with the addition of high amount of competing anions, significant Cr (VI) retentions could be obtained.
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Bin, Manaf Ishak. « Ceramers from aqueous polymer solutions of poly(ethylene oxide) ». Thesis, Loughborough University, 2001. https://dspace.lboro.ac.uk/2134/36083.
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The combination of inorganic and organic components in single materials makes accessible an immense new area of materials science that has profound implications in the development of novel materials, exhibiting a wide range of multifunctional properties. The so-called "sol-gel" process is normally used for the production of an inorganic phase within an organic polymer or cross-linkable oligomers. When the domain size of such materials is reduced to nanometer levels and the phases are interconnected, the hybrid materials are usually called "ceramers". The systems considered in this work are based on a water-soluble polymer, poly(ethylene oxide) (PEO) and silica (SiO2) networks produce by the sol-gel method. The PEO precursor solution was prepared by dissolving the resin in water at room temperature. Tetraethoxysilane (TEOS) was used as the alkoxysilane precursor. Different types of alkoxysilane precursors were prepared, based on TEOS and silane coupling agent. The silica present in the hybrid system was formulated to be at 25%, 35% and 50% w/w.
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Weaver, Jonathan Victor Mark. « Synthesis and aqueous solution properties of controlled-structure methacrylic polymers ». Thesis, University of Sussex, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399822.
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Swanton, Stephen W. « The physico-chemical characterisation of zirconium polymers in aqueous solution ». Thesis, University of Bristol, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481029.
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Seuring, Jan [Verfasser], et Seema [Akademischer Betreuer] Agarwal. « Polymers with Upper Critical Solution Temperature in Aqueous Solution / Jan Seuring. Betreuer : Seema Agarwal ». Marburg : Philipps-Universität Marburg, 2012. http://d-nb.info/102807249X/34.
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Huang, Shuyue Huang. « COACERVATION AND PHASE BEHAVIOR OF AQUEOUS SOLUTIONS OF OPPOSITELY CHARGED POLYELECTROLYTES ». University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron152588540294971.
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Athavale, Advait D. « EXPERIMENTAL STUDY OF SATURATED NUCLEATE POOL BOILING IN AQUEOUS POLYMERIC SOLUTIONS ». University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1314758640.
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Chamier, Jessica. « Photoelectrochemical detection of inorganic mercury in aqueous solutions ». Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5213.
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Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: Due to the adverse human health effects associated with mercury (Hg) toxicity, an innovative method for inorganic mercury (Hg2+) determination in aqueous solutions was investigated. The method of Hg2+ determination involved the use of a Hg2+ selective chemosensor immobilised onto an indium tin oxide (ITO) coated electrode in a photoelectrochemical cell. Upon light activation and in the presence of Hg2+ the fluorescent chemosensor absorbed a photon, and charge separation would occur according to the nature of the semiconductive material coated onto the ITO substrate. The charge separators and semiconductors investigated were an n-type carrier TiO2, polyaniline (PANI) and copolymers of polyaniline and 2-bromoaniline (P[A-co-2- BrA]s) with different monomer ratios. The polymer and copolymer coated ITO working electrodes used in the Hg2+ sensitive photoelectrochemical cell were electrochemically evaluated. The results demonstrated that the ITO coated with PANI had superior conductive and semiconductive properties compared to ITO coated with P[A-co-2-BrA]s. The ITO glass substrates were coated with TiO2, PANI or P[A-co-2-BrA]s, followed by the fluorescent chemosensor, a rhodamine 6G derivative (RS). The electrodes were subsequently photoelectrochemically evaluated in a photoelectrochemical cell in the presence of Hg2+. The PANI-RS coated electrode behaved as a photocathode in the presence of Hg2+ under illumination. The PANI-RS photoresponse increased with increasing Hg2+ concentration in the range 10 to 150 μg L-1, with a limit of detection of 6 μg L-1. ITO coated with TiO2 (ITO/TiO2) followed by a composite of PANI and RS had a linear photoanodic response in the Hg2+ concentration range of 10 to 200 μg L-1 and a limit of detection of 5 μg L-1. ITO and ITO/TiO2 coated with the P[A-co-2-BrA]s and RS had considerably lower photoresponses towards Hg2+ in aqueous solutions compared to PANI-RS. The photoresponses decreased with increasing 2-bromoaniline content. The PANI and P[A-co-2-BrA]s coated ITO and ITO/TiO2 electrodes were then also coated with another rhodamine 6G derivative with a thiolactone moiety (RT). The PANI coated electrode yielded a photocathodic response in the Hg2+ concentration range 0.2 to 5 μg L-1. ITO coated with TiO2 had no photoresponse towards Hg2+ due to repulsive forces between TiO2 and the RT molecules. The photoresponses of the working photoelectrodes towards Hg2+ were further evaluated in a custom photoelectrochemical Hg2+ detector. The photoresponses of PANI-RS and PANI-RT gave qualitative results for the presence of Hg2+ in aqueous solutions in concentrations as low as 2 μg L-1.
AFRIKAANSE OPSOMMING: Weens die negatiewe gesondheids aspekte toegeskryf aan Hg2+ vergiftiging is ‘n nuwe innoveerende metode van Hg2+ deteksie in wateroplossings ondersoek. Die voorgestelde metode van Hg2+ deteksie behels die gebruik van ‘n Hg2+ selektiewe chemosensor geimmobiliseer op ITO elektrodes in ‘n fotoelektrochemiese sel. Met lig aktivering en in die teenwoordigheid van Hg2+, absorbeer die fluoreseerende chemosensor ‘n foton, gevolg deur lading skeiding, soos bepaal deur die aard van die halfgeleidende material wat op die ITO platjies bedek is. Die halfgeleiers wat ondersoek was, was TiO2, PANI en ko-polimere van PANI met 2-bromoanilien. Die polimeer en kopolimeer bedekte ITO werkende elektrodes wat in die Hg2+ sensitiewe fotoelektrochemiese sel gebruik is, is elektrochemies geevalueer. Daaruit is gevind dat ITO bedek met PANI superieure geleier en halfgeleier eienskappe het in vergelyking met die ITO wat bedek is met P[A-co-2-BrA] kopolimere. Die ITO glas plaatjies is bedek met TiO2, PANI en die P[A-co-2-BrA] kopolimere gevolg deur die fluoresseerende chemosensor, RS. Die elektrodes is onderskeidelik fotoelektrochemies getoets in ‘n fotoelektrochemiese sel in die teenwoordigheid van Hg2+. Die PANI-RS elektrode het soos ‘n fotokatode opgetree in die teewoordigheid van Hg2+ onder beligting. Die foto-reaksie van die PANI-RS elektrode teeonoor Hg2+ het liniêr toegeneem van 10 μg L-1 tot 150 μg.L-1 met ‘n limiet van deteksie op 6 μg L-1. ITO/TiO2 wat bedek is met ‘n samestelling van PANI en RS het ‘n fotoanodiese reaksie gehad teenoor Hg2+ in die liniêre reeks van 10 tot 200 μg L-1 met ‘n deteksie limiet van 5 μg L-1. ITO en ITO/TiO2 bedek met die P[A-co-2-BrA] kopolimere het heelwat laer fotoreaksies getoon teenoor Hg2+ in waterige oplossings Die fotoreaksie het afgeneem met toeneemende 2-bromoanilien inhoud van die kopolimeer. Die PANI en P[A-co-2-BrA] kopolimere bedekte ITO en ITO/TiO2 elektrodes is verder bedek met ‘n tweede rhodamine 6G afgeleide, RT. Die ITO/PANI bedek met RT het weer ‘n fotokatodiese reaksie gehad teenoor Hg2+ in die konsentrasie interval 0.2 tot 5 μg L-1. Die ITO/TiO2 elektrode bedek met die PANI-RT samestelling het geen fotoreaksie gehad teenoor Hg2+ weens afstotende kragte tussen die TiO2 and RT molekules. Die fotoreaksies van die verskeie werkende elektrodes teenoor Hg2+ is verder getoets in ‘n tuisgemaakte fotoelektrochemiese Hg2+ detektor. Die fotoreaksies van die PANIRS en PANI-RT samestellings op ITO het kwalitatiewe resultate gelewer vir die teenwoordigheid van Hg2+ in waterige oplossings in konsentrasies tot so laag soos 2 μg L-1.
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Lanzaro, Alfredo. « Microscopic flows of aqueous polyacrylamide solutions : a quantitative study ». Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/microscopic-flows-of-semidilute-polymer-solutions-a-quantitative-study(0741b854-c4f8-4c6b-a3f3-0eb821969a6c).html.
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Lee, Shun Yin. « The flocculation of charged particles in aqueous solutions by cationic polyelectrolytes ». Thesis, University College London (University of London), 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322484.
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Saulzet, Sylvie Isabelle. « Formation of supramolecular structures in aqueous solution and their interactions with surfaces ». Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301149.
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Ariyo, Adeyemi Idowu. « Droplet Dynamics of Aqueous Polymeric Solutions on Solid Surfaces ». University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1236212747.
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Herhut, Marcel [Verfasser]. « Thermodynamic Modeling of Protein Solubility in Aqueous Polymer/Salt Solutions / Marcel Herhut ». München : Verlag Dr. Hut, 2016. http://d-nb.info/1084387050/34.
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Sinn, Cornelia G. « Ion binding to polymers and lipid membranes in aqueous solutions Ionenbindung an Polymeren und Lipidmembranen in wässrigen Lösungen / ». [S.l. : s.n.], 2004. http://pub.ub.uni-potsdam.de/2004/0077/sinn.pdf.
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Sinn, Cornelia G. « Ion binding to polymers and lipid membranes in aqueous solutions : Ionenbindung an Polymeren und Lipidmembranen in wässrigen Lösungen ». Phd thesis, Universität Potsdam, 2004. http://opus.kobv.de/ubp/volltexte/2005/186/.
Texte intégralRésumé :
Ziel dieser Arbeit ist die Untersuchung der Ionenbindung an Polymeren und Lipidmembranen in wässrigen Lösungen. Im ersten Teil dieser Arbeit wurde der Einfluss verschiedener anorganischer Salze und Polyelektrolyte auf die Struktur des Wassers mit Hilfe Isothermer Mikrotitrationskalorimetrie (ITC) erforscht. Die Verdünnungswärme der Salze wurde als Maß für die Fähigkeit der Ionen, die geordnete Struktur des Wassers zu stabilisieren oder zu zerstören, verwendet. Die Verdünnungswärmen konnten auf Hofmeister Effekte zurückgeführt werden. Im Anschluss daran wurde die Bindung von Ca2+ an Natrium- Poly(acrylsäure) (NaPAA) untersucht. Mit Hilfe von ITC und einer Ca2+- selektiven Elektrode wurde die Reaktionsenthalpie und Bindungsisotherme gemessen. Es wurde gezeigt, dass die Binding von Ca2+ - Ionen an NaPAA stark endotherm und daher entropiegetrieben ist. Anschließend wurde die Bindung von Ca2+ an die eindimensionale Polymerkette mit der an ein Lipidvesikel mit denselben funktioniellen Gruppen verglichen. Es wurde beobachtet, dass die Ionenbindung –wie auch im Fall des Polymers- endotherm ist. Ein Vergleich der Ca2+- Bindung an die Lipidmembran mit der an das Polymer konnte zeigen, dass das Ion schwächer an die Membran bindet. Im Zusammenhang mit diesen Experimenten wurde auch beobachtet, dass Ca2+ nicht nur an geladene, sondern auch an zwitterionische Lipidvesikel bindet. Schließlich wurde die Wechselwirkung zweier Salze, KCl and NaCl, mit einem neutralen Polymergel, PNIPAAM, und dem geladenen Polymer PAA untersucht. Mit Hilfe von Kalorimetrie und einer kaliumselektiven Elektrode wurde beobachtet, dass die Ionen mit beiden Polymeren wechselwirken, unabhängig davon, ob diese Ladungen tragen, oder nicht.The goal of this work was to study the binding of ions to polymers and lipid bilayer membranes in aqueous solutions. In the first part of this work, the influence of various inorganic salts and polyelectrolytes on the structure of water was studied using Isothermal Titration Calorimetry (ITC). The heat of dilution of the salts was used as a scale of water structure making and breaking of the ions. The heats of dilution could be attributed to the Hofmeister Series. Following this, the binding of Ca2+ to poly(sodium acrylate) (NaPAA) was studied. ITC and a Ca2+ Ion Selective Electrode were used to measure the reaction enthalpy and binding isotherm. Binding of Ca2+ ions to PAA, was found to be highly endothermic and therefore solely driven by entropy. We then compared the binding of ions to the one-dimensional PAA polymer chain to the binding to lipid vesicles with the same functional groups. As for the polymer, Ca2+ binding was found to be endothermic. Binding of calcium to the lipid bilayer was found to be weaker than to the polymer. In the context of these experiments, it was shown that Ca2+ not only binds to charged but also to zwitterionic lipid vesicles. Finally, we studied the interaction of two salts, KCl and NaCl, to a neutral polymer gel, PNIPAAM, and to the ionic polymer PAA. Combining calorimetry and a potassium selective electrode we observed that the ions interact with both polymers, whether containing charges or not.
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Hua, Zan. « Synthetic nucleobase-containing acrylamide polymers and their applications in aqueous solutions ». Thesis, University of Warwick, 2018. http://wrap.warwick.ac.uk/106792/.
Texte intégralRésumé :
This thesis explores the synthesis and self-assembly of nucleobase-containing acrylamide amphiphiles and investigates their self-assembly behaviors and potential applications in aqueous solutions. In Chapter 1, the synthesis and self-assembly of block copolymers are briefly introduced. Then the effect of H-bonding interactions on self-assembly behaviours is highlighted. Finally, an overview of the synthesis, self-assembly and applications of synthetic nucleobase-containing polymers is presented. Chapter 2 investigates the effect of complementary nucleobase interactions within micellar cores on the morphologies of self-assemblies in aqueous solutions. Self-assemblies with different core sizes of thymine are fabricated and their morphological transitions with introducing complementary copolymers are studied as well. Chapter 3 systematically explores the pathway-dependent and complementary chain-selective morphological transitions of micelles with a thymine core. In addition, the complementary H-bonding within micellar cores is utilized to prepare a series of worms with different lengths and widths in aqueous media. Chapter 4 builds on the knowledge obtained in the previous Chapters. A series of mixed corona micelles are fabricated through a simple supramolecular ‘grafting-to’ approach. By introducing protein ligands and environment-sensitive fluorophores at the end of corona, the reveal and concealment of functional groups on the micelle surface through heating and cooling are investigated. Chapter 5 reveals the synergetic H-bonding and thymine photodimerization give a novel polymer fluorescent dots. A number of factors are investigated on the observed fluorescent properties, including the effect of blocking H-bonding interactions and changing the degree of core-crosslinking. Finally, Chapter 6 summarizes the conclusions of Chapters 2-5 and provides some insights and outlines for the future work.
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Furuya, Tsutomu. « Structure Formation and Physical Properties of Aqueous Polymer Solutions and Hydrogels with Additives ». Kyoto University, 2019. http://hdl.handle.net/2433/236625.
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Inaler, Ekrem. « Accelerated Aging Of Elastomers In Aqueous Media ». Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608119/index.pdf.
Texte intégralRésumé :
EPDM (Ethylene-Propylene-Diene Monomer)/PP (Polypropylene) based TPV (Thermoplastic Vulcanizate) was aged in a closed system at stabilized temperature and pressure at 80, 100 and 120oC in distilled water, detergent solution and shiner solution.
The variation in properties of TPV upon aging were followed by using DSC (Differential Scanning Calorimetry), TGA (Thermogravimetric Analysis), tensile testing, Shore A rubber hardness testing.
DSC analysis indicated that percent crystallinity of PP component in TPV increased at 100oC whereas crystal structure was deformed at 120oC. In addition to this, hardness test showed that the hardness of TPV remained almost constant in distilled water aging except 120oC water aging but TPV became softer in detergent and shiner solution upon all aging temperatures used in this study. Tensile testing confirmed the hardness analysis that the loss in mechanical properties of TPV was observed except 100oC water aging. TGA analysis showed that percent crystallinity increase causes enhancement in degradation temperature of EPDM/PP blend in air.
It is detected that TPV is quite resistant to 80oC aging, but TPV loses its resistance to preserve its characteristics at 120oC aging. It is also determined that aging media is as important as temperature to evaluate the performance of TPV. Moreover, it is decided that the rate of aging directly proportional to detrimental rate is arranged in an order from the slowest to the fastest as distilled water, detergent and shiner solution media.
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TAKINAMI, PATRICIA Y. I. « Obtenção de biopolímeros de gelatina por radiação ionizante ». reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23304.
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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-01-21T10:28:15Z
No. of bitstreams: 0Made available in DSpace on 2015-01-21T10:28:15Z (GMT). No. of bitstreams: 0
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Kalaikadal, Deepak Saagar. « Investigation of Bubble Dynamics in Pure Liquids and Aqueous Surfactant / Polymer Solutions Under Adiabatic and Diabatic Conditions ». University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1525167893347615.
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Liu, Dan. « Removal of Emerging Contaminants from Aqueous Solutions by Using Polymeric Resins ». Master's thesis, Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/149804.
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Civil EngineeringM.S.E.
The emerging contaminants (ECs) such as estrogen hormones, perfluorinated compounds (PFCs), bisphenol A (BPA) and 1, 4-dioxane have been detected in natural water bodies at a noticeable level worldwide. The presence of ECs in the aquatic environment can pose potential threats to aquatic organisms as well as human world. Ion-exchange is a highly efficient technology for the removal of heavy metal ions and natural organic materials (NOMs) due to the nature of exchanging similar charged ions. However, this technology has not been explored for removing ECs. In this study, four categories of ECs: estrogen hormones (12), perfluorinated compounds (10), bisphenol A and 1, 4-dioxane were used as model contaminants. The adsorption of each category of ECs onto various types of polymeric resins (MN100, MN200, A530E, A532E and C115) was investigated. The removal of ECs was tested under batch and column mode. The effects of pH, resin dosage, and contact time on the removal of ECs were studied in batch mode; isotherm and kinetics models were applied to fit the experimental data. Column experiments were conducted to verify the practicability of the polymeric resins. Adsorption results have shown that both MN100 and MN200 resins could efficiently remove estrogen hormones mixture (more than 95%), and bisphenol A (more than 80%) with the initial concentration of 100 ìg/L; A532E and A530E could remove perfuorinated compounds mixture (more than 99%) with the initial concentration of 100 ìg/L. As pH increased from 9 to 11, the adsorption capacity onto polymeric resins decreased dramatically for estrogen hormones such as 17á-ethinylestradiol, estriol, 17â-estradiol, 17á-estradiol, estrone, 17á-dihydroequilin and equilin as well as bisphenol A. The adsorption of estrogen hormones and bisphenol A onto MN100 and MN200 resins reached the equilibrium within 24 hours, whereas the adsorption of perfluorinated compounds onto A532E and A530E reached the equilibrium within 8 hours. It was also observed that the adsorption of PFCs largely depends on the C-C chain length. PFCs with longer chain yielded lower adsorption efficiency onto the ion-exchange resins A532E and A530E. Adding salinity decreased the first-order rate constants for the adsorption of bisphenol A onto MN100 and MN200 resins. Fixed-bed column experiment results with estrogen hormones mixtures confirmed that the polymeric resins were good candidates in the removal of estrogen hormones. Trimegestone was the first compound detected in the effluent in the column test while 17â-estradiol, 17á-estradiol were the last. 80% of the exhausted resins (MN100 and MN200) by bisphenol A were regenerated by using pure methanol as regeneration solution. Polymeric resins were not effectively removing 1, 4-dioxane from the aqueous solution.
Temple University--Theses
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Bellot-Ayreault, Mathilde. « Assemblages réversibles dirigés par liaisons hydrogène en solution aqueuse ». Paris 6, 2009. http://www.theses.fr/2009PA066614.
Texte intégralRésumé :
De nouveaux dérivés amphiphiles, de type bis-urées, ont été synthétisés pour l'étude de leur caractère auto-associatif en solution. En solvant polaire, et en particulier dans l'eau, ces amphiphiles s'organisent en objets unidirectionnels allongés, associés par liaisons hydrogène et interactions hydrophobes, pour former des polymères supramoléculaires dynamiques, ou polymères réversibles. L'auto-association dans l'eau est possible grâce à la protection des liaisons hydrogène à l'intérieur d'un micro-domaine hydrophobe. De faibles modifications de la structure chimique, typiquement un groupement méthyle, donnent des variations importantes de la viscosité, et ce même à faible concentration. De plus, dans l'eau, des solutions gélifiées sont obtenues autour de 60°C. La forme de ces assemblages a été déterminée par diffusion de neutrons aux petits angles et cryo-microscopie : il s'agit de rubans de section elliptique dans l'eau. Des structures tubulaires n'ont pas encore été mises en évidence, mais un contrôle fin de la structure supramoléculaire et des propriétés d'auto-association a néanmoins été obtenu. Finalement, des molécules hydrophobes ont été ajoutées à des solutions aqueuses de bis-urées afin d'étudier leur influence sur les propriétés et la structure des assemblages
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Hoskins, Alan Richard. « Mechanism of the dissolution of acrylonitrile based polymers in aqueous inorganic salt solutions ». Thesis, University of Bradford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287107.
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Dumetz, Andre C. « Protein interactions and phase behavior in aqueous solutions effects of salt, polymer, and organic additives / ». Access to citation, abstract and download form provided by ProQuest Information and Learning Company ; downloadable PDF file, 284 p, 2008. http://proquest.umi.com/pqdweb?did=1456290971&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Texte intégralRésumé :
Thesis (Ph.D.)--University of Delaware, 2007.Principal faculty advisor: Abraham M. Lenhoff, Dept. of Chemical Engineering, and Eric W. Kaler, College of Engineering . Includes bibliographical references.
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Coche, Liliane. « Préparation et étude électrochimique d'électrodes modifiées par des films de polymères rédox : application à la catalyse électrochimique rédox ». Grenoble 1, 1987. http://www.theses.fr/1987GRE10046.
Texte intégralRésumé :
Preparation d'electrodes de platine, palladium et rhodium modifiees par des films de polypyrrole et de poly (pyrrole-crologene). Application a la reduction electrochimique en milieu acetonitrile du dibromo-1,2 diphenyl-1,2 ethane
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Lumber, Darren. « Fluorescence studies of the dynamics of water soluble polymers in aqueous solutions and dispersions ». Thesis, Lancaster University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340644.
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Biver, Claudine. « Formation d'amas dans les solutions de polymères hydrosolubles : influence sur le comportement en solution d'un polysaccharide végétal : le scléroglucane ». Paris 6, 1986. http://www.theses.fr/1986PA066199.
Texte intégralRésumé :
Etude par diffusion de la lumière, rhéologie et pouvoir rotatoire de l'évolution des propriétés des solutions de scléroglucane en fonction de plusieurs paramètres (température, concentration, ph. . . ). Mise en évidence d'un processus d'agrégation à température ambiante et existence d'une transition sol-gel à basse température 7°. Proposition d'une structure du polymères qui permette d'envisager deux mécanismes d'association.
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Liang, Ting. « Supramolecular polymers of triarylamines : studies in aqueous medium and covalent capture of their self-assemblies ». Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAF044/document.
Texte intégralRésumé :
Pour contrôler les systèmes chimiques complexes, les outils de la chimie supramoléculaire s’avèrent puissants et représenteront certainement une des technologies clef du 21e siècle. En effet, la réversibilité intrinsèque des liaisons chimiques impliquées dans la formation d'assemblages supramoléculaires apporte à ces systèmes un caractère "adaptatif", capable de réorganiser leur structure en fonction des conditions environnementales. Ce comportement s’avère totalement inédit malgré le grand nombre d’études effectuées sur cette famille de molécules du fait de ses propriétés photoactives. Au cours des dernières années, notre groupe a synthétisé de nombreux dérivés de triarylamines (TAAs), qui ont été utilisés pour produire des architectures supramoléculaires multifonctionnelles. En fonction des différents groupements qui substituent ce coeur TAA, diverses morphologies ont pu être observées et les propriétés physiques de ces auto-assemblages produits dans des solvants non polaires tels que les solvants chlorés ou le toluène se sont également révélées variées (propriétés cristal-liquide, conductrices, plasmoniques...). A partir de ces travaux, mon projet de thèse consistait en deux objectifs: a) étudier l'auto-assemblage et les propriétés de ces composés TAA dans des solvants polaires comme l'eau ou le méthanol. Pour cela, comme tenu du caractère hydrophobe des TAAs, il s'avérait nécessaire de synthétiser de nouvelles molécules incorporant des groupements latéraux favorisant la solubilité dans de tels solvants; b) stabiliser les auto-assemblages de triarylamine par polymérisation covalente et étudier les propriétés physiques associées à ces nouvelles structures. Pour cela, il convenait de synthétiser de nouvelles molécules incorporant des groupements polymérisables sur les chaines latérales, qui n'influençaient pas les propriétés d'auto-assemblages des TAAs. [...]Based on the unique directionality and reversibility of non-covalent interactions, supramolecular self-assembly works as an elegant methodology to construct multifunctional hierarchical architectures. Inspired by nature, where water provides a vital environment for biological process such as biomacromolecular folding, water-soluble supramolecular polymers have been prepared and studied so as to mimic related biological systems. On the other hand, owing to the dynamic nature of their non-covalent bonds, supramolecular polymers often lack mechanical robustness. Thus, cross-linking strategies have been developed in order to combine highly ordered molecular arrangement inherent to the sef-assembly and mechanical robustness of the covalent backbone, which might bee promising to reach functional materials for practical applications. In this thesis, we focus on well-designed triarylamine molecules which are known to self-assemble into supramolecular polymers with excellent physical properties, as discovered by our group. In particular, molecules studied in this manuscript are based on tris-amide triarylamine scaffold known to produce self-assemblies with metallic conductivity and self-healing behavior. First, we studied the self-assemblies of three novel tris-amide triarylamine derivatives decorated with either poly(ethylene glycol) (PEG), peptide or cyanine dyes side chains on the three amide positions in polar solvents, i.e. either water or methanol. Characterizations by various physico-chemical techniques (NMR, UV-Vis absorption, fluorescence, infrared spectroscopies, microscopies, scatterings) demonstrated the formation of fibrillar aggregates for all molecules in such polar environments. Overall, this study suggest that the triarylamine core act as the main driving force for the self-assembly into columnar aggregates while side chains ensure solubility in these solvents and/or favor the formation of chiral architectures. In a second study, we investigated the formation of tris-amide triarylamine supramolecular polymers decorated with norbornene and siloxane end side chains, which could be further used to freeze the self-assembled structures by ring opening metathesis polymerization and sol-gel methods, respectively. [...]
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Mathur, Aditi. « Optimization of Polymer Enhanced Diafiltration system by studying copper removal from aqueous solutions using Lambda-carrageenan ». Digital WPI, 2008. https://digitalcommons.wpi.edu/etd-theses/993.
Texte intégralRésumé :
"Excessive discharge of heavy metals has been one of the major causes of water pollution worldwide. Various traditional methods of heavy metal removal have been devised but certain drawbacks like high cost, high energy requirement, and the production of toxic sludge have limited their use. Hence, biosorption is one of the alternative methodologies. This study combined biosorption and diafiltration in an attempt to optimize Polymer Enhanced Diafiltration to study copper removal from aqueous solutions by the use of a biopolymer, lambda-carrageenan. Lambda-carrageenan was studied as a biosorbent owing to properties such as low cost, good water solubility, non-gelling nature and the presence of sulfate groups which can sequester cations. Conditions for binding such as pH, temperature and concentration of copper and lambda-carrageenan were studied. Equilibrium dialysis experiments were performed to study the metal ion membrane transport kinetics and to determine the metal ion binding capacity and strength of the copper-biopolymer association. Rheological measurements were performed to determine how the viscosity of lambda-carrageenan changes with increase in shear stress and with increase in metal concentration. The solution was found to be shear thinning. However, with increase in metal concentration, viscosity was found to increase when high concentrations of polymer (8 g/L and 12 g/L) were used. Solution viscosity was found to decrease with increase in metal concentration when 4 g/L of polymer was used. Polymer Enhanced Diafiltration studies showed no leakage of the polymer through the membrane and no significant binding elsewhere in the PEDF system. It also showed an impressive retention of copper inspite of a rather high metal ion-polymer dissociation constant suggesting a yet not understood series of events occurring on the membrane of the PEDF system. Lambda-carrageenan is a linear polysaccharide, which might be stacking up on the membrane after forming layers, and not allowing any free metal ion to escape. Other reasons could be the sieving effect, degradation of the polymer due to shear and compaction of molecule on metal binding such that the polymer is not itself escaping through the membrane, but also not allowing the free metal ion to escape. Hence, this study suggests the need for more information on the metal-polymer interactions on the surface of the membrane by designing a direct observation experiment with a mini-tangential flow filtration system."
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ZHANG, JUNTAO. « EXPERIMENTAL AND COMPUTATIONAL STUDY OF NUCLEATE POOL BOILING HEAT TRANSFER IN AQUEOUS SURFACTANT AND POLYMER SOLUTIONS ». University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1077304904.
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Syrbe, Axel. « Polymer incompatibility in aqueous whey protein and polysaccharide solutions : phase separation phenomena and microgel particle formation / ». Online version, 1997. http://bibpurl.oclc.org/web/29745.
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Okada, Yukinori. « Theoretical study of phase separation and thermoreversible gelation in aqueous solutions of temperature-sensitive polymers ». 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/50615.
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学位授与大学：京都大学；学位の種類：博士(工学)；学位記番号：工博第2818号；学位授与年月日：2007-03-23Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第13076号
工博第2818号
新制||工||1409(附属図書館)
UT51-2007-H349
京都大学大学院工学研究科高分子化学専攻
(主査)教授 田中 文彦, 教授 吉﨑 武尚, 教授 瀧川 敏算
学位規則第4条第1項該当
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Ismail, Hani Khalil. « Novel battery chemistries using electrically conducting polymers synthesised from deep eutectic solvents and aqueous solutions ». Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/39875.
Texte intégralRésumé :
Here we describe the fabrication and testing of novel cells using a conducting polymer membrane, Zn metal anode and a deep eutectic solvent electrolyte. Several different polyaniline-modified electrodes have been formed in various deep eutectic solvents (DESs) and aqueous media using cyclic voltammetry, and subsequently characterised using the electrochemical quartz crystal microbalance (EQCM). The morphologies of the obtained polymers have also been characterised using scanning electron microscopy (SEM), atomic force microscopy (AFM) and 3D optical microscopy. The more compact and dense polyaniline (PANI) films were achieved in DESs, while the films produced from aqueous media exhibited open structures of increased porosities. EQCM showed that the motion of mobile species between films and electrolyte during redox cycling, via the related change in mass, is different in DESs compared to aqueous media; a contributory factor is the higher viscosity and ionic nature of the latter. The electrochemical stabilities and capacitances of these polymers were studied after incorporation of graphite (GR) particles or metal oxides. Graphite particles improved the power and energy densities, as well as the stability of polymers, compared with their ‘pure’ counterparts. The capacity retention of the ternary nanocomposites (PANI/MoO2/GR electrode grown from Oxaline) was 87 %, whereas the lowest retention was found for pure PANI was 13 % after 300 charge–discharge cycles. The PANI composite has been successfully used as a cathode, with Zn metal as anode, in wet batteries (aqueous salt/DES electrolyte). The battery suffered from a low coulombic efficiency of only 51 % in DES at room temperature, whereas at 50oC the efficiency was 97 %. At 50oC and a current density of 0.0625 mA cm-2, the battery showed an energy density of 104 Wh kg-1 at a power density of 75 W kg-1, and a capacity of 344 mA hg-1 for discharge at 0.09 mC cm-2.This suggests the polymer/graphite systems would be more suitable for a power source and battery applications than those using only the pure polymer.
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Kley, Marina [Verfasser]. « Silica particle formation from supersaturated aqueous solution and the influence of polymeric additives / Marina Kley ». Paderborn : Universitätsbibliothek, 2017. http://d-nb.info/1137943998/34.
Texte intégral
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Parry, Alison. « The Synthesis and Characterisation of Peg-Peptide Romp Polymers and their Self Assembly Behaviour in Aqueous Solution ». Thesis, University of Kent, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499663.
Texte intégral
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Islamoglu, Sezin. « Effect Of Ionic Strength On The Performance Of Polymer Enhanced Ultrafiltration In Heavy Metal Removal From Aqueous Solutions ». Phd thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/3/12607832/index.pdf.
Texte intégralRésumé :
Effect of ionic strength on the efficiency of heavy metal removal and recovery from aqueous solutions via continuous mode polymer enhanced ultrafiltration (PEUF) method was examined. Application of PEUF to divalent ions of cadmium, nickel and zinc after their prior linking with polyethylenimine (PEI) results in complete removal of metal ions from single component aqueous solutions at high pHs.
Binding ability and hence the extent of metal retention in high ionic strength medium exhibits differences between solutions containing single and multicomponent metal mixtures. In single component metal solutions, extent of retention decreases but
binding order of metals remains unaffected both in low and high ionic strength medium. But, in binary component metal mixtures, with increase in ionic strength the binding order of metals changes. Fractional separation of Cd, Ni and Zn ions from equimolar binary and ternary mixtures of these metals and effect of ionic strength on fractional separation efficiency
were investigated. Depending on pH and salt concentration and metal pairs present in the solution fractional separation can be achieved.Dynamic and static light scattering experiments were performed in order to gain insight about the conformational changes in PEI structure due to the pH and ionic strength alternations in solution. It was found that, the increase in ionic strength reduces the size of the macromolecules.
A chemical equilibrium model was developed in order to estimate the apparent binding constants of metal-PEI complexes. Based on the data obtained from continuous and batch mode PEUF experiments apparent binding constants were estimated and compared to reveal the performance differences between these operational modes.
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Ridell, Annika. « Characterisation of Aqueous Solutions, Liquid Crystals and Solid State of Non-ionic Polymers in Association with Amphiphiles and Drugs ». Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3607.
Texte intégral
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Garcia-Barron, Javier Enrique. « Synthesis and study of chelating polymers and their application to protein and metal separation from aqueous solutions using novel metal affinity interaction techniques ». Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/283931.
Texte intégralRésumé :
The main objective of this research work was the development, synthesis, and study of polymeric chelating derivatives. These derivatives were characterized in terms of their specific metal affinity interaction with biomolecules and metal ions. These engineered materials were used to test their feasibility as tools for separation of proteins and heavy metal ions from aqueous solutions using different affinity separation techniques. Linear and branched polymers were synthesized to create a variety of materials. Among the linear polymers synthesized was the chelated monomethoxy poly(ethylene) glycol (PEG-IDA). This derivative was used in metal affinity partitioning and metal affinity electrophoresis for fast protein-metal interaction analysis. Also a linear heterobifunctional poly(ethylene) glycol (Biotin - PEG - IDA) was synthesized and used as a tool to develop a modified enzyme-linked immuno sorbent assay (ELISA). A multi-armed high molecular weight chelating poly(ethylene) glycol (Star PEG-IDA) was prepared to enhance the separation of protein mixture in gel permeation chromatography. Iminodiacetic poly(ethyleneimine) (PEI-IDA) was prepared and used as a soluble chelating polymer in complexation-ultrafiltration studies for heavy metal ion removal from aqueous solutions. Similar PEIs were also used as casting polymers for the synthesis of affinity adsorbents useful in chromatographic applications. Either as a soluble macromolecule or as a casting polymer for the preparation of adsorbents, PEI chelated derivatives were used for ultratrace metal ion preconcentration and metal ion separations. All polymeric materials prepared were characterized using analytical techniques which include elementary analysis, atomic absorption, UV and IR spectroscopy, high performance liquid chromatography and several colorimetric assays for the determination of end groups and product purity. Metal affinity separation techniques studied with the aforementioned derivatives included: affinity partitioning, affinity electrophoresis and affinity size exclusion for protein purification; affinity complexation-ultrafiltration and metal ion affinity chromatography for removal of heavy metal. Efficient separation of protein mixtures were achieved based on selective affinity by some of the chelated polymers here described and extremely high metal adsorption capacities were found for some of the PEI-based adsorbents prepared. Even though, some of these techniques are still in developmental stages, the results are very promising and encouraging for biotechnical and environmental applications.