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Association behavior of diblock copolymers with pH-responsive and thermoresponsive blocks in aqueous solutions
Škorňa, Adam ; Štěpánek, Miroslav (advisor) ; Raus, Vladimír (referee)
Univerzita Karlova Přírodovědecká fakulta Studijní program: Makromolekulární chemie Studijní obor: Makromolekulární chemie Bc. Adam Škorňa Asociační chování dvojblokových kopolymerů s pH-responsivními a termoresponsivními bloky ve vodných roztocích Associationbehavior of diblock copolymers with pH-responsive and thermoresponsive blocks in aqueous solutions Diplomová práce Školitel: prof. RNDr. Miroslav Štepánek. Ph.D. Praha 2022/2023 Abstract The growing number of double-responsive block copolymers with well-defined physical properties have beensynthesizedbycontrolledradical polymerization inthe last decades.These block copolymers (BCPs) can have interestingarchitecture and very complex phase behaviour, resulting in so-called "schizophrenic" micellization. It was suggested previously that BCPs consisting of a polyelectrolyte block and a thermoresponsive block may exhibit so-called "schizophrenic" micellization: In selective solvents, depending on pH and temperature, solvophilic (core-forming) blocks of these BCPs may become solvophobic (corona-forming). In this thesis, we conducted a study of double-responsive diblockcopolymer poly(di-[ethylene glycol] methyl ether methacrylate)-b-poly(2-[diisopropylamino] ethyl methacrylate) (PDEGMA-b-PDIPAEMA), inwhich PDEGMA acts as thermoresponsive blockwithLCST of 27...
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Study of self-assembly and degree of ionization of block copolymers using transmission electron microscopy and molecular simulations
Illés, Peter ; Nová, Lucie (advisor) ; Štěpánek, Miroslav (referee)
Responsive systems, such as block copolymers with solvent-affine blocks, can undergo self-assembly into structures like micelles or vesicles. These assem- blies are highly sensitive to slight changes in external conditions, like pH or temperature, leading to the formation or dissolution of micelles. When one of the polymer blocks is a weak polyelectrolyte, its degree of ionization depends not only on the external conditions but also on the association state. This study focuses on investigating the size and degree of ionization of micellar struc- tures formed by polymer chains containing thermoresponsive and pH-responsive blocks. The investigation combines high-resolution transmission electron mi- croscopy and Hamiltonian Monte Carlo simulations to provide a comprehensive understanding of these micellar structures. 1
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Self-assemblies based on hydrophilic polymers in aqueous media
Fanova, Anastasiia ; Štěpánek, Miroslav (advisor) ; Pánek, Jiří (referee) ; Angelov, Borislav (referee)
This doctoral thesis is devoted to investigation of self-assemblies based on hydrophilic polymers (both homopolymers and block copolymers) in aqueous media. Specifically, we focused on two classes of systems: (i) hydrophilic polymers whose self-assembly in aqueous solutions is driven by association of terminal hydrophobic groups and (ii) double hydrophilic block polyelectrolytes whose self-assembly occurs via electrostatic complexation of polyelectrolyte blocks. For characterization of formed assemblies, we mostly used different scattering techniques (light scattering, small-angle X-ray scattering) in a combination with a number of supplementary methods including microscopy, fluorometry and calorimetry. Keywords: hydrophilic polymers, block copolymers, association, self-assembly, micelles, scattering
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The study of self-assembly governed by the formation of donor-acceptor complexes
Warzecha, Tomáš ; Starý, Ivo (advisor) ; Betík, Robert (referee)
The study of self-assembly governed by the formation of donor-acceptor complexes This work deals with the preparation of 2-[(3-carboxyphenyl)ethynyl]benzoic acid, which a represents simplified model of monodisperse (p-phenylen)ethynylene oligomers, functionalized by carboxylic groups. Such a dicarboxylic acid was synthesized via Sonogashira coupling and then taken over to a series of diesters with corresponding alcohols. The theoretical part contains concise introduction to nanoscience, self assembly and donor - acceptor (D-A) interactions. The most frequently used synthetic reactions - Sonogashira coupling and Steglich esterification are described. The experimental part deals with the preparation of dimeric dicarboxylic acid and corresponding esters with alcohols containing electronacceptor functional groups. The synthetized compounds were characterized by spectroscopic methods (NMR, MS, IR, UV/VIS) and elemental composition established by HR MS. Melting points were measured for crystalline compounds.
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The D-A and pi-pi interactions and their use in self-assembly
Rejchrtová, Blanka ; Starý, Ivo (advisor) ; Kotora, Martin (referee)
The D-A and π-π Interactions and Their Use in Self-Assembly Due to their well-defined shape, size and properties gold nanoparticles represent an advantageous platform for the study of non-covalent interactions between ligands anchored to their surface both in solution and in monolayers or thin films. The aim of this thesis was the synthesis of ligands for gold nanoparticles bearing an anchoring group at one end and a planar π-electron rich pyrene unit at the other. Six structurally variable ligands were prepared differing in the pyrene substitution pattern and the spacer between the aromatic part and the acetylated thiol function. Furthermore, a synthetic pathway leading to extended π-electron systems (both electron rich and electron poor) such as hexabenzocoronene derivatives and its fragments was explored. The key steps in the synthesis of these compounds are the cyclization reactions of alkynes leading to polycyclic intermediates and their ensuing cyclodehydrogenation (Scholl reaction). All of the prepared ligands and their intermediates were characterized by spectroscopic methods. The structure of the key hexakis(pentafluorosulfanyl-phenyl)benzene was confirmed by single crystal X-ray crystallography. The prepared ligands bearing a pyrene unit were deacetylated and anchored to the surface of...
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The D-A and pi-pi interactions and their use in self-assembly
Rejchrtová, Blanka ; Starý, Ivo (advisor) ; Kotora, Martin (referee)
The D-A and π-π Interactions and Their Use in Self-Assembly Due to their well-defined shape, size and properties gold nanoparticles represent an advantageous platform for the study of non-covalent interactions between ligands anchored to their surface both in solution and in monolayers or thin films. The aim of this thesis was the synthesis of ligands for gold nanoparticles bearing an anchoring group at one end and a planar π-electron rich pyrene unit at the other. Six structurally variable ligands were prepared differing in the pyrene substitution pattern and the spacer between the aromatic part and the acetylated thiol function. Furthermore, a synthetic pathway leading to extended π-electron systems (both electron rich and electron poor) such as hexabenzocoronene derivatives and its fragments was explored. The key steps in the synthesis of these compounds are the cyclization reactions of alkynes leading to polycyclic intermediates and their ensuing cyclodehydrogenation (Scholl reaction). All of the prepared ligands and their intermediates were characterized by spectroscopic methods. The structure of the key hexakis(pentafluorosulfanyl-phenyl)benzene was confirmed by single crystal X-ray crystallography. The prepared ligands bearing a pyrene unit were deacetylated and anchored to the surface of...
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The study of self-assembly governed by the formation of donor-acceptor complexes
Warzecha, Tomáš ; Starý, Ivo (advisor) ; Betík, Robert (referee)
The study of self-assembly governed by the formation of donor-acceptor complexes This work deals with the preparation of 2-[(3-carboxyphenyl)ethynyl]benzoic acid, which a represents simplified model of monodisperse (p-phenylen)ethynylene oligomers, functionalized by carboxylic groups. Such a dicarboxylic acid was synthesized via Sonogashira coupling and then taken over to a series of diesters with corresponding alcohols. The theoretical part contains concise introduction to nanoscience, self assembly and donor - acceptor (D-A) interactions. The most frequently used synthetic reactions - Sonogashira coupling and Steglich esterification are described. The experimental part deals with the preparation of dimeric dicarboxylic acid and corresponding esters with alcohols containing electronacceptor functional groups. The synthetized compounds were characterized by spectroscopic methods (NMR, MS, IR, UV/VIS) and elemental composition established by HR MS. Melting points were measured for crystalline compounds.
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Building blocks of hydrogen-bonded supramolecular polymers
Roudná, Štěpánka ; Svoboda, Jan (advisor) ; Zedník, Jiří (referee)
The connection of molecular monomers through non-covalent interaction (e.g. hydrogen bonding, π-π interaction, coordination bonding) enables the formation of supramolecular polymers. The major advantage of these bonds is their reversibility and consequently their ability to self-assembly or to disconnect depending on given conditions. This thesis examines the self-assembly through quadruple hydrogen bonding, which is strong and the resulting structures stable. Ureidopyrimidinon A and aromatic amines were always used as the starting compound for the preparation of monofunctional and bifunctional ureidopyrimidinones.
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