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Surface and mechanical properties of a-CSi:H and a-CSiO:H films
Plichta, Tomáš ; Shukurov, Andrey (referee) ; Klapetek, Petr (referee) ; Čech, Vladimír (advisor)
The dissertation thesis deals with the preparation and characterisation of a-CSi:H and a CSiO:H thin films prepared using the process of plasma enhanced chemical vapour deposition (PECVD). Tetravinylsilane (TVS) and its mixtures with argon and oxygen were used to deposit films on both planar substrates and fibre bundles. Main characterisation techniques were employed to study the topography of films, namely atomic force microscopy (AFM). Their mechanical properties were studied through nanoindentation; the nanoscratch test was used to assess the film adhesion to the substrate. Other analysed properties were internal stress and friction coefficient. The particular attention was paid to the work of adhesion and its determination. This knowledge was further applied to the preparation of surface treatments of glass fibres and, subsequently, polymer composites. Those were tested using the push-out test and the short beam shear test. Based on the results, the effects of deposition conditions and the relationships between the studied properties and quantities were determined.
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Sensitive Layers for Optical Biosensors and Protein Chips
Rodriguez Emmenegger, César ; Brynda, Eduard (advisor) ; Lynn, Nicholas Scott (referee) ; Shukurov, Andrey (referee)
Sensitive layers for optical biosensors and protein chips The goal of this thesis was the development of sensitive surfaces for optical affinity biosensors detecting in complex biological media. The practical application of these surface-based technologies has been hampered by protein fouling from biological media, in particular blood plasma, where the vast majority of relevant analytes are present. The work of the thesis was centred in three main foci: Design and preparation of antifouling and non-fouling surfaces Evaluation and conceptualisation of their resistance to fouling from blood plasma and serum as well as other biological fluids Preparation of sensitive layers for detection in complex biological media Three approaches were used to prepare protein resistance surfaces, i) ω-functional self-assembled monolayers (SAM), ii) end-tethered polymers and iii) polymer brushes prepared by surface initiated controlled radical polymerisation. Investigation of proteins in the blood plasma deposits on PEG- based surfaces revealed that some fouling is unavoidable in PEG-based surface modifications. A novel type of non-fouling polymer brushes based on poly[N-(2-hydroxypropyl) methacrylamide] challenged the accepted ideas for the design of protein resistant surfaces. For the first time a...
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Mechanical Properties of Hydrogels - Comparison between DMA and AFM Measurements of Elastic Modulus
Hofrichterová, Tereza ; Valentová, Helena (advisor) ; Shukurov, Andrey (referee)
Polymer hydrogels consist of polymer network that is able to absorb large amount of water. They have plenty of real-life applications - for example in medicine and diagnostics. The aim of this thesis is to study elastic modulus of several hydrogel samples by two different methods - dynamical mechanical analysis (DMA) and atomic force microscopy (AFM). Dynamical mechanical analysis represents a traditional method, which is expected to supply very reliable data. On the other hand - there has not been done much research in the field of studying mechanical properties with atomic force microscopy yet. This thesis should result into comparison of these two methods and describing effects that influence the measurement.
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Nanostructured films based on plasma polymers
Solař, Pavel ; Shukurov, Andrey (advisor) ; Vyskočil, Jiří (referee)
In this thesis we have studied growth and properties of thin films prepared by tilted deposition using sputtering. The construction of low pressure magnetron is presented. The influence of deposition conditions on formation of columnar structure using scanning electron microscope was studied. Formation of columnar structures of metals, composites metal-plasma polymer and plasma polymer is described. The influence of deposition conditions on surface roughness obtained by AFM is discussed. Chemical structure of composite and plasma polymer films has been determined using XPS and infrared spectroscopy.
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Synthesis of nanoparticles using gas aggregation sources
Hanková, Adéla ; Kylián, Ondřej (advisor) ; Shukurov, Andrey (referee)
This work focuses on the synthesis of thin films and nanoparticles of vanadium and its oxides. Thin films are fabricated by means of magnetron sputtering, while for the prepara- tion of nanoparticles a gas aggregation source is used. Produced thin films and nanopar- ticles are investigated and compared in terms of their morphology, optical properties and chemical structure. We also study the heating of both types of samples. All em- ployed diagnostics methods prove that oxidation of films and nanoparticles at 550 řC changes the samples to crystalline V2O5. Another investigated method of vanadium oxide nanoparticles preparation is based on the addition of oxygen into the deposition chamber. Changes in shape, size, bulk composition and thickness of the deposited layer of nanoparticles are demonstrated in comparison with nanoparticles fabricated in a pure argon atmosphere. On the other hand, the surface composition is similar for both meth- ods of preparation indicating spontaneous oxidation of the surface layer of both materials on ambient air. 1
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Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films
Nikitin, Daniil ; Shukurov, Andrey (advisor) ; Novák, Stanislav (referee) ; Straňák, Vítězslav (referee)
Title: Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films Author: Daniil Nikitin Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics/Charles University Abstract: The PhD thesis aims at the investigation of nanostructures based on plasma polymers. The main attention is paid to the combination of a gas aggregation cluster source with plasma-assisted vapor phase deposition for the fabrication of metal-polymer nanocomposites with bactericidal potential. Copper nanoparticles were incorporated into a biocompatible matrix of plasma polymerized poly(ethylene oxide) (ppPEO). The efficiency of such nanocomposite against multi-drug resistant bacteria was demonstrated. It was found that the segmental dynamics of the plasma polymer significantly changed in the presence of nanoparticles as revealed by the measurements of the dynamic glass transition temperature. The nanoscale confinement crucially influences the non-fouling properties of poly(ethylene oxide). A separate chapter is dedicated to the examination of the nanoparticle formation, growth and transport inside the source. Copper and silver nanoparticles were detected in situ in the gas phase...
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Multicomponent plasma polymers with spatially controlled properties
Pleskunov, Pavel ; Shukurov, Andrey (advisor) ; Čech, Vladimír (referee) ; Tichý, Milan (referee)
Title: Multicomponent plasma polymers with spatially controlled properties Author: MSc. Pavel Pleskunov Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Prof. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics / Charles University Abstract: Mixing of two (or more) polymers often leads to phase separation and to the formation of nanoscale architecture, which can be highly attractive in various applications including controllable drug delivery, fabrication of separation and solid electrolyte membranes, gas storage, etc. Different wet-chemistry techniques already exist to produce nanophase-separated polymers; however, capturing the resultant polymeric structure in a predictable manner remains a challenging task. In this thesis, a low-temperature plasma-based strategy is investigated for the production of multicomponent thin films of plasma polymers with spatially discriminated nanoscale domains. Gas aggregation cluster source is used for the fabrication of nanoparticles of plasma polymerized acrylic acid, whereas Plasma-Assisted Vapor Phase Deposition is used for the deposition of thin films of poly(ethylene oxide) plasma polymer. Embedding of nanoparticles into matrices of thermodynamically incompatible plasma polymer as well as...
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Surface and mechanical properties of a-CSi:H and a-CSiO:H films
Plichta, Tomáš ; Shukurov, Andrey (referee) ; Klapetek, Petr (referee) ; Čech, Vladimír (advisor)
The dissertation thesis deals with the preparation and characterisation of a-CSi:H and a CSiO:H thin films prepared using the process of plasma enhanced chemical vapour deposition (PECVD). Tetravinylsilane (TVS) and its mixtures with argon and oxygen were used to deposit films on both planar substrates and fibre bundles. Main characterisation techniques were employed to study the topography of films, namely atomic force microscopy (AFM). Their mechanical properties were studied through nanoindentation; the nanoscratch test was used to assess the film adhesion to the substrate. Other analysed properties were internal stress and friction coefficient. The particular attention was paid to the work of adhesion and its determination. This knowledge was further applied to the preparation of surface treatments of glass fibres and, subsequently, polymer composites. Those were tested using the push-out test and the short beam shear test. Based on the results, the effects of deposition conditions and the relationships between the studied properties and quantities were determined.
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Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films
Nikitin, Daniil ; Shukurov, Andrey (advisor) ; Novák, Stanislav (referee) ; Straňák, Vítězslav (referee)
Title: Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films Author: Daniil Nikitin Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics/Charles University Abstract: The PhD thesis aims at the investigation of nanostructures based on plasma polymers. The main attention is paid to the combination of a gas aggregation cluster source with plasma-assisted vapor phase deposition for the fabrication of metal-polymer nanocomposites with bactericidal potential. Copper nanoparticles were incorporated into a biocompatible matrix of plasma polymerized poly(ethylene oxide) (ppPEO). The efficiency of such nanocomposite against multi-drug resistant bacteria was demonstrated. It was found that the segmental dynamics of the plasma polymer significantly changed in the presence of nanoparticles as revealed by the measurements of the dynamic glass transition temperature. The nanoscale confinement crucially influences the non-fouling properties of poly(ethylene oxide). A separate chapter is dedicated to the examination of the nanoparticle formation, growth and transport inside the source. Copper and silver nanoparticles were detected in situ in the gas phase...
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