Dissertations / Theses: 'Polymer in dilute solution'

1

YANG, ZHENGNAN. "Kinetics of Polymer Chain Collapse in Dilute Solution." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1509377014210034.

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Zhao, Jiuzhou. "Convective Assembly of Rod-shaped Melanosome in Dilute Polymer Solution." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1462211308.

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3

Huang, Jin. "Extensional viscosity of dilute polymer solutions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0004/MQ46075.pdf.

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4

Harris, Owen John. "Unsteady flows of dilute polymer solutions." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319993.

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5

Harlen, Oliver Guy. "Strong flows of dilute polymer solutions." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358648.

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6

Yu, Kui 1967. "Multiple morphologies of polystyrene-b-poly(ethylene oxide) diblock copolymers in dilute solution." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36076.

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Multiple morphologies of self-assembled aggregates of polystyrene- b-poly(ethylene oxide) (PS-b-PEO) diblock copolymers in dilute solution have been studied. The PS blocks are relatively long compared to the PEO blocks. The aggregates are prepared by the addition of water or methanol to the copolymer solutions in N,N-dimethylformamide (DMF), dioxane, or tetrahydrofuran (THF) to induce the aggregation of the PS blocks. Aqueous solutions of the aggregates are obtained by dialysis with water. Morphologies are directly studied by transmission electron microscopy (TEM).
The morphogenic effect of the copolymer composition indicates that as the EO content in the diblock decreases, the morphology of the self-assembled aggregates changes progressively through spheres, rods, bilayers, and ultimately to inverted aggregates. The observed bilayers include lamellae, vesicles, tubules and large compound vesicles (LCVs), and the inverted aggregates include inverted (hollow) hoops with a hexagonal array and large compound micelles (LCMs).
The morphological transition from vesicles to inverted hoops is investigated, and a three-step mechanism is proposed. This mechanism involves a thickening of the vesicle walls accompanied by the formation of the hollow rods in the walls, and a decrease in the size of the original water core. Possible mechanisms of the formation of large vesicles from lamellae, as well as tubules and LCVs from vesicles are discussed.
The formation of the self-assembled aggregates with various morphologies is believed to be mainly controlled by the balance of three interactions arising from the core, the corona, and the core-solvent interface. Any factors, such as the addition of salt, which affect the balance will cause morphological changes. Accordingly, the morphogenic effects of added electrolytes, temperature, the common solvent, and the precipitant are studied. The study shows that various morphologies can be prepared from one diblock copolymer.

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7

Whang, Kyu-ho. "Static and Flow Properties of Dilute Polymer Solutions." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc501073/.

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Small weight percentages of certain high-molecular weight polymers added to liquids in turbulent flow through conduits can result in dramatic friction reduction. Although many current and potential uses of the drag reduction phenomenon exist, there is a fundamental problem: drag reduction efficacy decreases rapidly with flow time due to the mechanical degradation in flow of the added polymer. In this thesis study, dilute aqueous solutions of polyacrylamide were tested under turbulent flow conditions in an attempt to determine where mechanical degradation in flow occurs.

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Bhave, Aparna Vasant. "Kinetic theory for dilute and concentrated polymer solution study of nonhomogeneous effects." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/12553.

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9

McKinley, Scott Alister. "An existence result from the theory of fluctuating hydrodynamics of polymers in dilute solution." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1149020682.

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10

Ida, Daichi. "DILUTE SOLUTION PROPERTIES OF SEMIFLEXIBLE STAR POLYMERS." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/66202.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第14170号
工博第3004号
新制||工||1446(附属図書館)
26476
UT51-2008-N487
京都大学大学院工学研究科高分子化学専攻
(主査)教授吉﨑武尚, 教授田中文彦, 教授伊藤紳三郎
学位規則第4条第1項該当

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11

Xu, Zhuang. "PARTITIONING OF SOLVENT MOLECULES SURROUNGDING POLYMER CHIANS IN SOLVENT-SHIFTING PROCESS." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1555690517286259.

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12

Capone, Barbara. "Coarse-graining polymer solutions in the semi-dilute regime." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608924.

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13

Yan, Xuejia. "Drop-on-demand inkjet drop formation of dilute polymer solutions." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/42713.

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The research discussed in this dissertation was conducted to understand drop formation of inkjet printing with inks containing polymer. Solutions containing a water soluble polymer, poly ethylene oxide (PEO), with different molecular weights and polydispersities were used as inks. A flash photographic technique was used to visualize the whole process of DOD drop formation of dilute polymer solutions. The effects of driving signal, frequency and liquid properties on drop speed, drop size, breakup time and the formation of satellites were studied in detail. The addition of PEO increases the shear viscosity at all molecular weights, but the change is small for dilute solutions. However, the addition of a small amount of PEO can have a significant effect on the DOD drop formation process, increasing breakup time, decreasing primary drop speed and decreasing the number of satellites in some cases. The effects depend on both molecular weight and concentration. At lower molecular weights (14k and 35k g/mol), the effect of PEO was small when the drop formation process for the dilute solution was compared with that of a Newtonian liquid having similar shear viscosity, and the effect of PEO was small even at concentrations large enough that the solution does not fall in the dilute regime. As molecular weight is increased, the effects of PEO on DOD drop formation increase significantly, and the effects of concentration become important. These effects are explained by the fluid elasticity which increases with increasing in molecular weight and concentration. When the liquid jets out of the nozzle, the polymer chains are stretched, and thus depart from their ideal coiled state. As a result, an elastic stress develops in the liquid column and resists capillarity-driven pinch off from the nozzle and is responsible for the decrease in drop speed and longer breakup time. DOD drop formation data were shown to correlate closely with effective relaxation time, proposed by Tirtaatmadja based on Rouse-Zimm theory. When driving voltage amplitude is 44.2 V, two important parameters (breakup time and primary drop speed) in DOD drop formation for solutions containing monodispersed PEO and aqueous solutions containing mixtures of monodispersed PEO were closely predicted by correlation equations involving effective relaxation time . A mixture rule was developed to calculate the relaxation time for mixtures of monodispersed PEO. However, for polydispersed PEO, effective relaxation time was based on viscous molecular weight since the molecular weight distributions of the polydispersed PEO were unknown. When breakup time was plotted versus effective relaxation time for 1000k g/mol PEO, the data did not lie on the same line as that for the 100k and 300k g/mol PEO. This is believed to be due to the molecular weight distributions of the polydispersed PEO. When more than one species are present, viscous average molecular weight does not adequately account for the long chain species making up the polymer sample. DOD drop formation dynamics is highly affected by the actuating waveform, including the driving voltage, waveform shape, and frequency. The effects of parameters (jetting frequency, voltage amplitude and the shape of waveform) characterizing the signal were investigated. The open time and first drop problem were also studied. Research in this dissertation gives a better understanding of DOD drop formation process of polymer solutions, which may lead to improvement of inkjet printing quality for a variety of industry inks and polymer micro scale deposition and patterning in large areas.

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14

Radwan, Mostafa Abdel-Salam. "Characterisation of neutral and zwitterionic polymers in dilute solution." Thesis, University of Salford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304692.

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15

Drewniak, Marta. "Computer Simulations of Dilute Polymer Solutions: Chain Overlaps and Entanglements." Thesis, University of North Texas, 1996. https://digital.library.unt.edu/ark:/67531/metadc278086/.

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Chain conformations and the presence of chain overlaps and entanglements in dilute polymer solutions have been analyzed. The fundamental problem of existence of chain overlaps in dilute solutions is related to the drag reduction phenomenon (DR). Even though DR occurs in solutions with the concentration of only few parts per million (ppm), some theories suggest that entanglements may play an important role in DR mechanism. Brownian dynamics technique have been used to perform simulations of dilute polymer solutions at rest and under shear flow. A measure of interchain contacts and two different measures of entanglements have been devised to evaluate the structure of polymer chains in solution. Simulation results have shown that overlaps and entanglements do exist in static dilute solutions as well as in solutions under shear flow. The effect of solution concentration, shear rate and molecular mass have been examined. In agreement with the solvation theory of DR mechanism, simulation results have demonstrated the importance of polymer + polymer interactions in dilute solutions.

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Figueroa, Leonardo E. "Deterministic simulation of multi-beaded models of dilute polymer solutions." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:4c3414ba-415a-4109-8e98-6c4fa24f9cdc.

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We study the convergence of a nonlinear approximation method introduced in the engineering literature for the numerical solution of a high-dimensional Fokker--Planck equation featuring in Navier--Stokes--Fokker--Planck systems that arise in kinetic models of dilute polymers. To do so, we build on the analysis carried out recently by Le~Bris, Leli\`evre and Maday (Const. Approx. 30: 621--651, 2009) in the case of Poisson's equation on a rectangular domain in $\mathbb{R}^2$, subject to a homogeneous Dirichlet boundary condition, where they exploited the connection of the approximation method with the greedy algorithms from nonlinear approximation theory explored, for example, by DeVore and Temlyakov (Adv. Comput. Math. 5:173--187, 1996). We extend the convergence analysis of the pure greedy and orthogonal greedy algorithms considered by Le~Bris, Leli\`evre and Maday to the technically more complicated situation of the elliptic Fokker--Planck equation, where the role of the Laplace operator is played out by a high-dimensional Ornstein--Uhlenbeck operator with unbounded drift, of the kind that appears in Fokker--Planck equations that arise in bead-spring chain type kinetic polymer models with finitely extensible nonlinear elastic potentials, posed on a high-dimensional Cartesian product configuration space $\mathsf{D} = D_1 \times \dotsm \times D_N$ contained in $\mathbb{R}^{N d}$, where each set $D_i$, $i=1, \dotsc, N$, is a bounded open ball in $\mathbb{R}^d$, $d = 2, 3$. We exploit detailed information on the spectral properties and elliptic regularity of the Ornstein--Uhlenbeck operator to give conditions on the true solution of the Fokker--Planck equation which guarantee certain rates of convergence of the greedy algorithms. We extend the analysis to discretized versions of the greedy algorithms.

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17

Dunlap, Paul N. "Studies of Flow Modification and Polymer Conformation in Extensional Flows of Dilute Polymer Solutions." Diss., Pasadena, Calif. : California Institute of Technology, 1986. http://resolver.caltech.edu/CaltechETD:etd-03212008-080541.

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18

Sawatari, Nobuo. "DYNAMIC LIGHT SCATTERING BY OLIGOMERS AND POLYMERS IN DILUTE SOLUTION." 京都大学 (Kyoto University), 2002. http://hdl.handle.net/2433/149854.

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19

LaRiviere, Daniel John Christopher. "Viscometric properties of dilute lubricating oil-polymer solutions over a wide temperature range." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ30961.pdf.

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20

Muggli, Mark W. "Physical Aging and Characterization of Engineering Thermoplastics and Thermoplastic Modified Epoxies." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/40509.

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In this work the relationship between physical properties, such as physical aging and relaxation time distributions, and chemical structure for a variety of polymeric systems were investigated. Although there is a vast amount of physical aging data for polymers, most of these studies do not attempt to correlate structure with physical aging. Therefore, a set of engineering thermoplastics was examined with the goal of relating certain of their characteristic molecular dimensions to their mechanical and volumetric physical aging attributes.Another series of polymeric materials, based on a poly(ether sulfone) backbone, and having various endgroups differing in size, was also studied to determine physical aging rates and relaxation time distributions. Furthermore, it was concluded that the density of the poly(ether sulfones) increased while the glass transition temperature decreased as the endgroup became smaller.Thermoplastic toughened epoxies were also examined to clarify the importance of covalent bonds between toughener and epoxy on physical aging, relaxation time distributions and fracture toughness. In these studies the covalently bonded tougheners differed from their non-reactive counterparts in the rates of volumetric physical aging at high temperatures for the difunctional epoxy. The solvent resistance of the reactive thermoplastic toughened tetrafunctional epoxy was higher than the non-reactive thermoplastic toughened system. The tetrafunctional epoxies with the reactive toughener also had higher toughener glass transition temperatures.
Ph. D.

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21

Warren, M. Jason. "Viscometric behavior of dilute dewaxed base oil-polymer solutions over a wide temperature range." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ30992.pdf.

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22

Cocconi, Giacomo [Verfasser]. "Numerical Study on the Propagation of Turbulent Fronts in Dilute Polymer Solutions / Giacomo Cocconi." Karlsruhe : KIT Scientific Publishing, 2019. http://d-nb.info/1202884873/34.

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23

Caritey, Jean-Philippe. "Relation entre la modification chimique de précurseurs hydrophiles d'origine naturelle et leurs propriétés en solution diluée et semi-diluée." Rouen, 1994. http://www.theses.fr/1994ROUES013.

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Nous avons déterminé l'influence de différentes modifications chimiques sur les propriétés en solution de polysaccharides d'origine végétale déjà largement utilisés dans l'industrie pétrolière, notamment pour des questions de protection de l'environnement: l'hydroxypropylguar (HPG) est un galactomannane neutre. La fixation d'une petite quantité de longues chaînes alkyles hydrophobes lui procure un caractère associatif. Nous avons mis en évidence qu'en régime dilué, l'établissement d'interactions intramoléculaires se traduit par l'adoption d'une conformation plus compacte ce qui explique la diminution de la viscosité intrinsèque. En régime semi-dilué, des interactions intermoléculaires majoritaires sont responsables d'une forte augmentation de viscosité des solutions; la formation d'un réseau de type gel est possible si la concentration en polymère est suffisante. Nous avons observé que la salinité, la température, une faible quantité de tensio-actif et un degré de substitution en groupe hydrophobe élevé, provoquent un renforcement de ces interactions. L'étude de l'effet du temps et de la réversibilité des associations met en évidence l'importance du facteur cinétique. L'ensemble des propriétés permet d'envisager l'application dans des formulations de forage. La carboxyméthylcellulose (CMC) est un éther de cellulose anionique dont les propriétés en solution peuvent être profondément modifiées par une modification chimique appropriée. La nature du substituant et le site de substitution sont les deux paramètres dont on s'est attaché à montrer l'importance. La fixation de groupes hydrophobes sur les fonctions carboxylate provoque une baisse importante de la solubilité, alors qu'un groupe hydrophile fixé sur les fonctions alcool l'améliore. Cependant, une attention particulière doit être portée lors de la réaction de modification afin d'éviter toute dégradation de la chaîne principale du polymère

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24

Pierleoni, Carlo. "Scaling laws in dilute polymer solutions at equilibrium and in flow by molecular dynamics simulation." Doctoral thesis, Universite Libre de Bruxelles, 1992. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212941.

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25

Siochi, Emilie J. "Dilute solution studies of molecular weight distributions of nitrocellulose, modified lignins and PMMA graft polymers." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54423.

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Dilute solution properties of three difficult-to-analyze macromolecular systems were investigated and clarified. Two were notorious for having highly time-in-solution dependent properties, nitrocellulose and lignin, while the third was an ideal model branched methacrylate polymer with which to examine unanswered questions in polymer hydrodynamic behavior. Gel permeation chromatography with a differential viscosity detector (GPC/DV) was employed to study the dilute solution properties of various polymers, specifically their absolute molecular weight distributions and hydrodynamic behavior. The study was divided into three parts. The first part focused on the time dependent change in molecular weight of nitrocellulose. Samples having 12.58% and 13.5% levels of nitration were investigated in THF and EtOAc. GPC/DV, LALLS, FT-IR and intrinsic viscosity experiments revealed that the materials existed as associated molecules in solution which decreased in molecular weight upon storage to extents dependent on the solvent. The second part was an examination of the hydrodynamic behavior of hydroxypropylated lignins using GPC/LALLS/DV and VPO. These materials were found to increase in molecular weight upon storage in solution due to association. Special precautions had to be taken in running experiments to obtain the correct molecular weights and molecular weight distributions. The last part involved a fundamental study of PMMA-g-PMMA's having similar molecular weights but containing different levels of branching. Variable temperature GPC/LALLS/DV was employed to obtain molecular weight distributions, branching parameters, average chain dimensions and information on the hydrodynamic behavior of these branched systems. Samples containing up to 40% of long chain branching were found to obey the universal calibration analytic scheme of GPC.
Ph. D.

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Veitshans, Thomas. "Propriétés des réseaux permanents ou temporaires dans les polymères : gonflement ; RMN et simulation ; RMN et écoulement." Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10206.

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Sont presentes trois projets permettant de mieux comprendre la structure de systemes polymeres et les liens entre cette structure et les grandeurs de l'approche rmn. Dans la partie etude de gels bimodaux nous mettons en evidence une relation entre des parametres rmn et des moments de la distribution de la longueur des chaines entre deux nuds. Nous developpons en outre une version bimodale du theoreme c#* que nous verifions. Le deuxieme projet est intitule simulation de la relaxation de l'aimantation transversale d'une chaine gaussienne en solution diluee, fixee aux extremites. Nous creons un code de calcul adapte a cette premiere etude numerique dans le domaine de l'approche rmn aux systemes polymeres. Le potentiel de telles etudes est montre par une analyse de la relaxation de l'aimantation transversale m#x(t). La partie relaxation de l'aimantation transversale d'un fluide de polymeres enchevetres et soumis a un cisaillement concerne l'etude du reseau temporaire des enchevetrements. Nous presentons un dispositif original permettant d'observer par rmn des fluides cisailles. Nous avons observe qu'un cisaillement n'a pas d'influence sur la fonction m#x(t) d'une solution semi-diluee dans la gamme des taux de cisaillement etudies. Cette etude necessite d'etre completee par des etudes subsequentes que nous specifions. Par ailleurs, d'autres etudes consecutives aux trois projets de recherche sont proposees. En particulier, nous decrivons une etude qui mettrait en evidence l'objectif commun des trois projets : mieux comprendre la physique de systemes polymeres et cela grace aux moyens que nous donne l'approche rmn.

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27

Smith, Steven Richard. "Equilibrium and dynamic properties of side-chain liquid-crystalline polymers in dilute nematic solutions." Case Western Reserve University School of Graduate Studies / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=case1058202738.

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28

Cocconi, Giacomo [Verfasser], and B. [Akademischer Betreuer] Frohnapfel. "Numerical Study on the Propagation of Turbulent Fronts in Dilute Polymer Solutions / Giacomo Cocconi ; Betreuer: B. Frohnapfel." Karlsruhe : KIT-Bibliothek, 2017. http://d-nb.info/1163320323/34.

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29

Lapp, Alain. "Synthese, conformation et interactions de molecules lineaires et ramifiees de polydimethylsiloxane : mise en evidence de lois d'universalite." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13108.

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Synthese du polydimethylsiloxane etudie et etude de l'hydrosilation se produisant au cours de la reticulation en solution semidiluee, relation entre la longueur de correlation et la concentration. Interactions a trois corps dans le styrene, solvant theta du pdmsi

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Charpentier, Dominique. "Carboxyméthylcelluloses à hydrophobie variable : propriétés associatives en solution diluée et semi-diluée." Rouen, 1998. http://www.theses.fr/1998ROUES012.

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Les propriétés associatives de dérivés de la carboxyméthylcellulose à hydrophobie variable ont été étudiées en solution diluée et semi diluée. Deux types de réactions de modification chimique, par greffage d'une alkylamine, ont été réalisés sur la fonction acide de la CMC. Le premier greffage de chaînes alkyle fait intervenir l'activation des fonctions acide par la dicyclohexylcarbodiimide (L-CMC). La seconde réaction consiste à former le sel d'ammonium de la CMC qui est ensuite deshydraté à 140°C (I-CMC). Des dérivés mono et bigreffés ont ainsi pu être obtenus. Une étude RMN 1H et 13C a permis de confirmer les taux de greffage déterminés par dosage conductimétrique et d'établir la répartition des substituants sur le motif anhydroglucose. Il a été montré que la phase d'activation des fonctions acides par la dicyclohexylcarbodiimide s'accompagne d'une dégradation de la chaîne principale (L-CMC). Les études de diffusion de la lumière et de viscosimétrie ont mis en évidence la présence de macromolécules agrégées en régime dilué. Il existe un taux de greffage critique (4 %) en hexadecylamide à partir duquel les associations hydrophobes de type intermoléculaire deviennent majoritaires, ce qui permet une amélioration des propriétés épaississantes (L-CMC). Le système bigreffé présente, en régime semi dilué, une augmentation spectaculaire des propriétés associatives liée à l'augmentation de l'hydrophobie (présence de 30 % de groupes butyle) et à la diminution de la densité de charge. Les systèmes bigreffés (I et L) et monogreffés (I) ont des propriétés rhéologiques particulières qui suggèrent l'existence de plusieurs niveaux d'organisation hydrophobe. L'influence de la force ionique sur le pouvoir viscosifiant des solutions en régime dilué et semi dilué varie en fonction de l'hydrophobie des systèmes. L'incorporation d'un tensioactif neutre (Triton X100) dans les solutions de polymères mono et bigreffés en régime dilué et concentré, dans l'eau et dans NaCl 0,05 M, a confirmé l'existence de zones de jonctions hydrophobes très denses.

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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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Rawiso, Michel. "Etude structurale de macromolecules lineaires par diffusion de neutrons." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13209.

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Shen, Licheng. "Investigation of the removal and recovery of metal cations and anions from dilute aqueous solutions using polymer-surfactant aggregates." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:33afa911-3ffb-484e-8db5-b6843928f175.

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Dilute metallic ion treatment (< 10 mg/L) remains a challenge in water purification and resource recovery. A novel and inexpensive treatment process that employs polymer-surfactant aggregates (PSAs) has been developed and applied to remove and recover dilute metallic ions, such as Cr3+, Rh3+, Cd2+, Fe(CN)6 3- and CrO42-, from industrial process and effluent. At the heart of this process is a material that comprises a colloidal structure of polymers and surfactants, named a polymer-surfactant aggregate (PSA), that trap metallic ions. The ion loaded PSAs then coalesce and settle out. The flocs are then treated separately by acid-base wash to recover the ions in a concentrated salt and regenerate the polymer and surfactant. The regenerated polymer and surfactant can then be recycled without a deterioration of removal ability in the next cycle. This process is simple, uses low energy, and generates little material loss or discharge. The thesis is divided into three main parts: fundamentals, cation treatment and anion treatment. First, the mechanism of formation of PSAs and their interactions with metallic ions are investigated using surface tension and electrical conductivity measurements. Both measurements reveal that the PSA is formed by surfactant monomers binding to the oppositely charged polymer chains and forming micelle-like aggregates via hydrophobic and electrostatic forces. These aggregates, like micelles, can bind to the oppositely charged metallic ions, but the surfactant concentration required is a few orders of magnitude lower than that required for micelle formation. The resulting nano-size PSA has a large surface area to volume ratio, and can effectively treat dilute aqueous streams. Each PSA consists of positive and negative charges. Within a near charge neutralisation range, they can quickly self-flocculate to simultaneously remove metallic ions and settle the flocs out of aqueous solutions. Correlating the removal efficiency of ions with surface tension and electrical conductivity measurements, the results suggest that the PSA is indeed responsible for removing the ions from the streams. Based on the fundamentals, a PSA process consisting of three stages (removal, recovery and recycle) is developed to treat metal cations in dilute streams. At the removal stage, polymer and surfactant (i.e. removal agent) are used to form PSAs and trap 99% of 0.1 mM metal ions into flocs. At the recovery stage, a small amount of acid solution is added to leach out 95% of the trapped metal ions into a concentrated salt, and then using a base solution to completely dissolve and regenerate the removal agent. After that, the removal agent are recycled in the next cycle without the need for any make-up, and little deterioration of removal ability is found. The same three-stage process is also applied to recover dilute metallic anions. As the targeted ions are negatively charged, the charge of polymer and surfactant used and the order of acid-base wash are reversed as compared with the cation treatment process. The PSA process is robust under different conditions, e.g. pH, temperature, salinity and organic contaminants. Such a sustainable process thus has potential applications for the efficient removal and recovery of dilute metallic ions during process effluent water treatment.

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34

Bagassi, M'hammed. "Comportement hydrodynamique des macromolécules dans les milieux poreux fins en régime de déformation faible." Brest, 1986. http://www.theses.fr/1986BRES0004.

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Filtration d'un polyelectrolyte (polyacrylamide hydrolyse polydisperse et de grande masse moleculaire) a travers des membranes ayant des pores cylindriques bien definis. Influence du champ de vitesse de deformation du rayon de pore et de la force ionique de facon a pouvoir comprendre les mecanismes de passage et proposer un modele d'interpretation. Influence de la concentration

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Ng, Ricky Chiu-Yin Leal L. Gary Leal L. Gary. "Semi-dilute polymer solutions in strong flows : Part I. Birefringence and flow modification in extensional flows. Part II. Chaotic mixing in time-periodic flows /." Diss., Pasadena, Calif. : California Institute of Technology, 1990. http://resolver.caltech.edu/CaltechETD:etd-05172007-154209.

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36

Dupas, Adeline. "Dégradation mécanique de solutions de polymères et ses impacts en récupération assistée d'hydrocarbures." Phd thesis, Université de Bretagne occidentale - Brest, 2012. http://tel.archives-ouvertes.fr/tel-00830622.

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Le polymer flooding est une des techniques de récupération assistée des hydrocarbures (RAH) ; elle consiste à injecter une solution de polymères de forte masse moléculaire afin de déplacer plus efficacement le pétrole emprisonné dans la roche. Cependant, une limite importante de cette technique est la possible dégradation mécanique des polymères au cours de l'injection et dans le réservoir, due à une scission des chaînes macromoléculaires induite par l'écoulement. Ce travail de thèse a pour objectif de mieux comprendre les mécanismes et scénarios de scission, mais aussi leur impact sur le procédé de polymer flooding. Nous nous sommes intéressés au seuil de dégradation mécanique de solutions de poly(oxyde d'éthylène) et de de polyacrylamide partiellement hydrolysé, pour différents régimes de concentration (solutions diluées et semi-diluées) en régime laminaire et inertiel, et pour des solvants de différentes qualités. L'étude de la dégradation mécanique des solutions et de leur impact sur les propriétés rhéologiques a été menée à l'aide de différents dispositifs de dégradation et de différents rhéomètres, dont un dispositif microfluidique en élongation ; ces techniques de mesure ont été combinées à des mesures de distribution de masses moléculaires par chromatographie d'exclusion stérique couplée à la diffusion de lumière. L'étude montre en premier lieu qu'une composante élongationnelle est indispensable pour dégrader les chaînes macromoléculaires en solution. Les résultats mettent aussi clairement en évidence que les mécanismes de dégradation sont très différents en régime dilué et semi-dilué. En régime dilué, la dégradation mécanique des solutions de polymères est indépendante du régime d'écoulement et affecte préférentiellement les macromolécules de fortes masses, avec une scission en milieu de chaîne. En revanche, en régime semi-dilué, la dégradation mécanique dépend du régime de l'écoulement : en écoulement laminaire, la dégradation est gouvernée par le réseau d'enchevêtrements et la scission des chaînes est aléatoire, tandis qu'en régime inertiel, les chaînes se dégradent comme en régime dilué, avec le même scénario de scission en milieu de chaîne. Par ailleurs, les résultats montrent que les propriétés rhéologiques en élongation peuvent être très fortement impactées par la dégradation mécanique. Enfin, les résultats de l'étude préliminaire des propriétés d'injectivité dans un milieu poreux d'une solution de polymère semi-diluée faiblement dégradée montrent que la dégradation mécanique améliore l'injectivité du polymère aux abords du puits.

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Callet, Françoise. "Influence de la structure, de la conformation et des traitements post fermentation sur les propriétés du xanthane en solution." Grenoble 1, 1987. http://www.theses.fr/1987GRE10120.

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Influence du taux de substitution des chaines laterales en groupements acetyle et pyruvate sur les proprietes intrinseques de la molecule et sur la rheologie des solutions. Influence des traitements thermiques apres fermentation sur les proprietes en solution

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38

Mutin, Hubert. "Etude de la gelification physique du poly (chlorure de vinyle)." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13117.

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Etude en solution concentree (gel) et en solution diluee (pregel) cinetique. Etude des agregats formes en solution diluee (petite particule de gel gonflee de solvant). Mise en evidence de deux types de noeuds de reticulation: noeuds stables formant rapidement et fondant a haute temperature et noeuds moins parfaits se formant lentement et fondant a basse temperature

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39

Xiong, Yong-Liang. "Numerical Investigation on Drag Reduction and Two-Dimensional Turbulence in Diluted Polymer Solutions." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14141/document.

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Les polymères jouent un rôle important sur la réduction de la traînée et la modification de la structure des écoulements. Nous avons utilisé le modèle Oldroyd-B pour étudier l’effet de la viscoélasticité de solutions de polymères dilués sur des écoulements en deux dimensions autour d’obstacles dans un canal. Les obstacles sont pris en compte par la méthode de pénalisation volumique et des condition aux limites artificielles sans réflexion sont imposées à la sortie du canal. La discrétisation est effectuée par des schémas performants en différences finies et la résolution par une méthode multigrille. Les simulations numériques sont effectuées pour une large gamme de nombres de Reynolds et de nombres de Weissenberg. Les caractéristiques détaillées des écoulements viscoélastiques sont analysées et comparées entre elles et celles de l’écoulement du fluide sans polymère. En particulier les jeux de paramètres conduisant à une augmentation ou à une baisse de la traînée. Enfin les effets du polymère sur des écoulements turbulents sont aussi analysés
Polymer plays an important role on the drag reduction and modiﬁcation of the structure of ﬂow. In this thesis, Oldroyd B model is employed to study the effectof viscoelasticity for polymer solutions diluted by two-dimensional direct numerical simulation. The obstacles are taken into account by penalization method. The artiﬁcial boundary condition is imposed without any reﬂection on the channel outlet. Flow pasta cylinder is investigated in detailed by present numerical methods. The numerical codes are valid for predicting the drag force and capturing the important character of viscoelastic ﬂow by comparing with experimental and other numerical results. The drag map of the cylinder is obtained at a wide range of Reynolds number and Weissenberg number space. The detailed characteristics of viscoelastic ﬂow are reported in the thesis. The effects of polymer on two-dimensional turbulent ﬂow are also discussed by grid turbulent ﬂow

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40

Webster, Lee. "Polyelectrolyte complex formation in dilute aqueous solution." Thesis, University of Salford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360472.

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Akbari, Saeed. "Morphology and Dynamics of Catenanes in Dilute Solutions and at Liquid/Liquid Interface." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1544538754254472.

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42

Garcia, Sakai Victoria. "Polymer solution themodynamics." Thesis, Imperial College London, 2002. http://hdl.handle.net/10044/1/12024.

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Roy, Tuhin Kumar. "The computer simulation of dilute solution particle dynamics." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357751.

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44

Teetsov, Julie Ann. "Photophysical characterization and near-field scanning optical microscopy of dilute solutions and ordered films of alkyl-substituted polyfluorenes /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004384.

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45

Mendez-Santiago, Janette. "Extensions of the theory of dilute solutions." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/11850.

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46

Rodarte, Alma Isabel Marín. "Predispersed solvent extraction of copper from dilute aqueous solution /." This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-07282008-134126/.

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47

Scharf, John E. "Dermal absorption of a dilute aqueous solution of malathion." [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000045.

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48

Rodarte, Alma Isabel MarÃn. "Predispersed solvent extraction of copper from dilute aqueous solution." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/38846.

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Predispersed Solvent Extraction (POSE) was used to extract copper ions from dilute acidic aqueous solution. POSE is based on the principle that there is no need to comminute both phases. All that is necessary is to comminute the solvent phase prior to contacting it with the feed. This is done by converting the solvent into aphrons. which are micron-sized globules encapsulated in a soapy film. Since the aphrons are so small, it takes a long time for the solvent to rise to the surface under the influence of gravity alone. Therefore, the separation is expedited by piggy-back flotation of the aphrons on especially prepared gas bubbles, which are somewhat larger than aphrons and are called colloidal gas aphrons (CGA). Polyaphrons of various types were studied extensively. The apparatus used to generate the polyaphrons was upgraded. The residence time distribution of a liquid in the polyaphron generator was determined. The particle size distribution of polyaphrons was determined using photo-microscopy and sedimentation among other methods. Batch tests were done using both conventional and POSE. Results showed that POSE approaches equilibrium much faster than conventional extraction. Equilibrium isotherms were drawn and empirical equilibrium relationships were developed. The dynamics of the kinetics of the extraction was modeled using film theory. Equipment for the POSE process was built. Experiments were carried out in continuous mode and the process was optimized. An empirical statistical equation was developed for the extraction process in continuous mode. Depending on the aqueous to solvent ration, more than 99% copper can be extracted.
Ph. D.

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49

Scharf, John E. MD. "Dermal Absorption Of A Dilute Aqueous Solution Of Malathion." Scholar Commons, 2003. https://scholarcommons.usf.edu/etd/1466.

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Malathion is a commonly used organophosphate pesticide on field crops, fruits, nut trees, vegetables, livestock, agricultural premises, and land. The approved uses also include mosquito and medfly control. These uses can result in human skin contact. The purpose of this study is to evaluate the human skin absorption of malathion for the purpose of assessing the risks associated with aqueous solution exposures following applications. Aerial applications can result in solubilized malathion in swimming pools and other waters that may be contacted. Human volunteers were selected and exposed to aqueous solutions of malathion at various concentrations. Participants submerged their arms and hands in twenty liters of dilute malathion solution in either a stagnant or stirred environment. The "disappearance method" was applied by measuring malathion concentrations in the water before and after human subject exposure to the water for various periods of time. Malathion was measured using Gas Chromatography. No measurable skin absorption was detected in 42% of the participants. Measurable skin absorption among the remaining 58% of participants resulted in doses that were more than an order of magnitude less than the minimal dose necessary to cause a measurable change in red blood cell acetylcholinesterase (RBC-AChE). Extrapolation of these results to a mathematical model for recreational swimmers and bathers exposed to contaminated swimming pools and surface waters typically detected after bait application again are an order of magnitude below the doses needed to cause a detectable change in RBC-AChE. These data indicate that exposure to aqueous malathion following usual aerial bait applications is not appreciably absorbed, and therefore, it is not a public health hazard.

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Houzelle, Marie-Christine. "Dérivés amphiphiles associatifs de la pectine diverses voies de synthèse : étude comparative des propriétés physicochimiques des solutions aqueuses en régimes dilué et semi-dilué." Vandoeuvre-les-Nancy, INPL, 1998. http://www.theses.fr/1998INPL111N.

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La pectine est un polysaccharide anionique extrait des végétaux supérieurs et, en particulier, de l'écorce des fruits et des légumes. Ce polymère a été modifié chimiquement par fixation de chaines alkyles en C₁₂, C₁₆ et C₁₈, par trois voies de synthèse différentes, de manière à obtenir des dérivés associatifs dans lesquels les chaines apolaires sont associées au squelette polymère par des liaisons covalentes et/ou des liaisons ioniques. Les propriétés physico-chimiques des différents dérivés hydrophobisés résultants ont été étudiées de façon comparative par viscosimétrie, spectrométrie de fluorescence, en rhéologie et par des mesures de tension de surface, dans l'eau pure ou en présence de sels. Quel que soit le mode de synthèse et donc de fixation des chaines hydrophobes au polymère, tous ces dérivés présentent des propriétés associatives. En régime dilué, des interactions intramoléculaires se mettent en place, conduisant à une diminution de la viscosité macroscopique du milieu. En régime plus concentré, des interactions hydrophobes intermoléculaires s'établissent, conduisant à l'obtention de solutions aqueuses de très haute viscosité, voire même de réseaux tridimensionnels physiquement pseudo - réticulés ayant l'apparence d'hydrogels. Cependant, à coté de ces ressemblances, les chaines hydrophobes ne s'organisent pas au niveau moléculaire de la même façon, selon qu'elles sont associées au squelette polysaccharidique de façon covalente ou ionique. Cette différence de structure se traduit au plan macroscopique, en particulier par des propriétés de surface et des comportements rhéologiques sensiblement dissemblables.

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Dissertations / Theses on the topic 'Polymer in dilute solution'

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