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Hydrogels amino-dextran-surfactant: phase diagram
Daňková, Kristýna ; Hurčíková, Andrea (referee) ; Pekař, Miloslav (advisor)
This bachelor thesis deals with a study about hydrogel systems based on the physical interactions of the oppositely charged particles, specifically interactions between positive polyelectrolyte and negative detergent. The phase diagrams were created based on the visual evaluation of results of the laboratory experiment, which is a part of this thesis, for in advance chosen concentration of the polymer diethylaminoethyl-dextran hydrochloride and detergents sodium dodecyl sulphate and sodium tetradecyl sulphate. These phase diagrams characterize incurred dextran systems.
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Complexes of aminoclays and polyelectrolytes
Málková, Ivana ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
This thesis deals with the preparation of aminoclay and its products resulting from the interaction of aminoclay with natural polyelectrolyte. The theoretical part deals with the study of aminoclay and selected polyeletrolytes, which were used in the experimental part of the thesis. Potassium pectate, sodium alginate and sodium hyaluronate were chosen as polyelectrolytes. The aim was to let these two groups of compounds interact and to observe the formation of an aminoclay polyelectrolyte complex, taking form of a gel or a precipitate when appropriate concentrations were chosen. The resulting products were characterized in appearance and pH of the products was measured.
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Interaction of weak polyelectrolytes with multivaltent ions
Staňo, Roman ; Košovan, Peter (advisor) ; Heyda, Jan (referee)
By means of molecular simulations, we study dissociative behavior of weak polyacids with added mutlivalent salt. Weak polyacids are macromolecules that bear weak acid groups, therefore, their ionization varies with pH. The titration curve of such an acid deviates from the ideal one - its ionization is suppressed because of the strong repulsion between charged groups on the polyacid contour. The presence of salt in solution of a polyacid enhances the ionzation due to the effects of electrostatic screening and counterion condensation. Up to now, the influence of the salt valency on the weak polyacid ionization has not been explored, although it plays an important role in biological processes. In this thesis, we examine weak polyacid solutions with added salt of various cation valencies (+1,+2,+3) at fixed charge ratio of salt cations to po- lymer segments. We show that increasing the salt valency promotes the polyelectrolyte ionization in a manner which is different from the effect of increasing ionic strength. A higher counterion valency leads to a lower value of the critical Manning parameter, initiating strong counterion condensation which results in additional ionization due to ion-ion correlations between the condensed counterions and charged groups of the polyelectrolytes.
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Preparation and properties of building blocks of specialty polymers
Šichová, Kristýna
This Diploma Thesis presents results obtained by solution of two partial projects: a) Preparation of monomers from renewable sources using metathesis and tandem hydrogenation catalyzed with ruthenium compounds - project solved during my Erasmus stay at the Université de Rennes 1 in France; b) Preparation and properties of ,-bis(tpy)quarterthiophene oligomers carrying ionic side groups as oligomonomers for polyelectrolyte conjugated dynamers - project solved at the Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague. Project a): Self-metathesis of 1,2-epoxyhex-5-ene (but-3-enyloxirane) and its cross-metathesis with methyl acrylate and acrylonitrile catalyzed with ruthenium compounds as well as tandem design of these metatheses and consecutive hydrogenation of their products by gaseous hydrogen have been optimized. The following influences have been studied and tuned: (i) type of the catalyst (Grubbs, Hoveyda, Zhan) and its concentration and method of dosing, (ii) concentration of reactants and additives, (iii) type of solvent, and (iv) reaction temperature. Reactions were monitored by the GC, GC and MS methods and the products were characterized by the NMR method. Methyl 6,7-epoxyheptanoate (methyl 5-oxiranylpentanoate) obtained by the tandem...
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Preparation and properties of building blocks of specialty polymers
Šichová, Kristýna ; Svoboda, Jan (advisor) ; Sedláček, Jan (referee)
This Diploma Thesis presents results obtained by solution of two partial projects: a) Preparation of monomers from renewable sources using metathesis and tandem hydrogenation catalyzed with ruthenium compounds - project solved during my Erasmus stay at the Université de Rennes 1 in France; b) Preparation and properties of ,-bis(tpy)quarterthiophene oligomers carrying ionic side groups as oligomonomers for polyelectrolyte conjugated dynamers - project solved at the Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague. Project a): Self-metathesis of 1,2-epoxyhex-5-ene (but-3-enyloxirane) and its cross-metathesis with methyl acrylate and acrylonitrile catalyzed with ruthenium compounds as well as tandem design of these metatheses and consecutive hydrogenation of their products by gaseous hydrogen have been optimized. The following influences have been studied and tuned: (i) type of the catalyst (Grubbs, Hoveyda, Zhan) and its concentration and method of dosing, (ii) concentration of reactants and additives, (iii) type of solvent, and (iv) reaction temperature. Reactions were monitored by the GC, GC and MS methods and the products were characterized by the NMR method. Methyl 6,7-epoxyheptanoate (methyl 5-oxiranylpentanoate) obtained by the tandem...
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Self assembly of polyelectrolytes in aqueous solution (dissipave particle dynamics)
Šindelka, Karel ; Limpouchová, Zuzana (advisor) ; Kolafa, Jiří (referee)
Title: Self-assembly of polyelectrolytes in aqueous solutions (dissipative particle dynamics) Author: Karel Šindelka Department: Faculty of science, Charles University in Prague Supervisor: Doc. Ing. Zuzana Limpouchová, CSc. Consultant: Doc. Ing. Martin Lísal, DSc. Abstract In the thesis, the coarse-grained dissipative particle dynamics (DPD) is used for the study of self-assembly of equimolar mixtures of oppositely charged symmetric block PEs with one PE block (either strong polycation or strong polyanion) and one readily water-soluble neutral block in aqueous media. In the first part of the diploma thesis, the principles of DPD simulations are described and the correct implementation of electrostatic interactions in the DPD method is demonstrated on the example of counterion (Manning) condensation. In the second main part, the effect of the blocks solubility, incompatibility and the interplay of different forces on electrostatic assembly is investigated. The cor- responding neutral systems are also simulated for comparison. The study shows that the hydrophobicity of the PE backbone and the incompatibility of blocks sig- nificantly affects the electrsotatic co-assembly. The presence of opposite charges on different chains promotes the aggregation process and the aggregation number in- creases in comparison...
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Study of barrier and transport properties of polyelectrolytes using diffusion techniques in hydrogels
Valentová, Kristýna ; Kalina, Michal (referee) ; Smilek, Jiří (advisor)
This diploma thesis was focused on study of barrier and transport properties of selected polyelectrolytes in hydrogel matrices by using diffusion techniques. The study of these properties was performed in horizontal diffusion cells where is observed the change in diffusion probe concentration over time. Diffusion experiments were performed on an agarose hydrogel with the addition of alginate, hyaluronic acid, polystyrene sulfonate, humic acids and as a model probe rhodamine 6G was used. Important parts of this thesis are also the methods which characterize the substances and hydrogel matrices such as rheology and potentiometric titration. The main aim of this diploma thesis was to investigate the effect of interactions between passing model dye (rhodamine 6G) and the appropriate gel (agarose + polyelectrolyte) on the fundamental diffusion parameters (effective diffusion coefficient, lag time, etc.).
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