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Nanoclusters coatings for biomedical applications
Divín, Radek ; Kylián, Ondřej (advisor) ; Hanuš, Jan (referee)
Title: Nanoclusters coatings for biomedical applications Author: Radek Divín Department: Department of Macromolecular Physics (110. 32-KMF) Supervisor: RNDr. Ondřej Kylián, Ph.D. Abstract: The copper nanocluster films were prepared with the aid of the gas cluster aggregation source based on the principle of material sputtering from the magnetron target to the relatively high pressure of the working gas (Ar). The nanocluster films prepared in this way were subsequently overlapped with the layer of plasma polymer deposited by RF magnetron sputtering from the nylon polymer target in the atmosphere of the working gas (Ar, 2 Pa). A repetition of this procedure enabled to prepare nanocomposite layers having a multilayer character. These layers were subsequently investigated with regard to their morphology, chemical composition, surface wettability and optical properties. The chemical composition of the surface layer formed by nanocomposite films was determined by the X-ray photoelectron spectroscopy (XPS). It turned out that the chemical surface composition of prepared nanocomposites was not markedly influenced by the presence of the Cu nanoclusters. The morphology of prepared films was studied by the scanning electron microscopy (SEM) and the atomic force microscopy (AFM), which showed that the resulting...
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Ultrathin films deposited by means of magnetron sputtering and their characterization
Petr, Martin ; Kylián, Ondřej (advisor) ; Straňák, Vítězslav (referee) ; Tichý, Milan (referee)
Presented work is focused on the deposition and characterization of thin and ultrathin plasma polymer films, then also on the preparation of nanocomposites metal/plasma polymer. The characterization of plasma polymer films was partly done in-situ without exposing the samples to the atmosphere. The thickness of prepared films was measured by spectral ellipsometry, the chemical composition was measured by XPS. The morphology and optical properties of deposited films were measured ex-situ. It is shown that during the initial stages of growth the properties of plasma polymer films depend on their thickness and also on the material of the substrate. Many interesting applications were explored for prepared nanocomposites metal/plasma polymer. They can be used as superhydrophobic coatings, gradient coatings, substrates for Raman spectroscopy or as antibacterial coatings. Moreover, special optical properties of prepared nanocomposites were studied in detail. Presented work has an experimental character.
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Study of electric properties of nanocomposit material
Ovsík, Jiří ; Rozsívalová, Zdenka (referee) ; Polsterová, Helena (advisor)
This work deals with the electrical properties of nanocomposite materials. Samples for the experiment are made of epoxy resin as matrix and titanium dioxide TiO2 as nanofillers in varying percentage performance. Measurements are temperature dependent components of the permittivity, dissipation factor and resistivity. Furthermore, the internal resistivity is observed with regard to the percentage performance of a sample of nanoparticles.
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Structure and Properties of Collagen/HAP Nanocomposite Networks
Kopuletá, Ema ; Lehocký,, Marián (referee) ; Amler,, Evžen (referee) ; Jančář, Josef (advisor)
Polymerní biomateriály jsou jedním ze současných populárních témat vzhledem k možnosti potenciální aplikace v tkáňovém inženýrství a řízeného dávkování léčiv v organismech. Kolagen je jako jeden z nejčastěji se vyskytujících proteinů zvláště zajímavý díky svým rozmanitým vlastnostem bez imunoreakce organismu příjemce. Tato práce je zaměřena na samouspořádávací procesy, kinetiku, obecné zákonitosti řídící proces samouspořádání a mechanické vlastnosti kolagenních roztoků. Dále je zkoumán efekt hydroxyapatitových nanočástic na samouspořádávání kolagenu a mechanické vlastnosti výsledných nanokompozitních hydrogelů. Jsou objasněny možné mechanismy interakcí mezi kolagenem I a hydroxyapatitem spolu s popisem vývoje struktury a vlastností na různých úrovních struktury. Byly měřeny a molekulárně interpretovány závislosti viskoelastických veličin na smykové rychlosti spolu s viskoelastickým chováním. Dále byla studována struktura kolagenních scaffoldů a určen vliv HAP a síťování. Závěrem byly diskutovány výsledky v souvislosti s jejich aplikovatelností v tkáňovém inženýrství chrupavek tvrdých tkání a v regenerativní medicíně.
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Study of electric properties of nanocomposites
Libra, Miroslav ; Rozsívalová, Zdenka (referee) ; Polsterová, Helena (advisor)
The present master´s thesis deals with the electrical properties of nanocomposite materials. Samples for the experiment are made epoxi resin and oxides TiO2 and Al2O3 as nanofillers in different percent performace. The samples nanocomposites are measured temperature dependence of the resistivity inside, dissipation factor and relative permittivity. It discusses the effect of the filler on the resulting electrical properties of the polymer.
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Study of electrical properties of nanocomposites
Ovsík, Jiří ; Rozsívalová, Zdenka (referee) ; Polsterová, Helena (advisor)
The present work deals with the electrical properties of nanocomposite materials. Samples for the experiment are made of epoxy resin as a matrix and oxides TiO2, Al2O3, WO3, SiO2 as nanofillers in 0.5 and 1 percent performance. The experimental samples are measured in temperature and frequency dependence of relative permittivity, dissipation factor, rezistivity and are broken down by the influence of filler on the electrical properties of the polymer. Attention is also paid to the mechanical properties of nanocomposites.
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The influence of nanoparticles on isothermal crystallization rate of isotactic polypropylene
Miškolci, Michal ; Jančář, Josef (referee) ; Bálková, Radka (advisor)
This diploma thesis deals with the study of isothermal crystallization of nanocomposite materials based on isotactic polypropylene (iPP) and nanosilica, depending on the volume fraction (0, 2, 4 and 6 %) and type of silica and the crystallization temperature. Fumed silica and four types of silica with different surface treatment were used as filler. The crystallization performed at temperatures 136, 138, 140 and 142 °C has been studied in-situ using polarized optical microscope and the crystallization rate was evaluated from the growing radius of spherulites. It can be stated that particles of silica have been inbuilt into the spherulites due to the linear growth of spherulites of all composite materials. The most significant increase of the crystallization rate of iPP was caused by fumed silica, the most significant decrease was caused by silica TS-720 at volume fraction 4 %. The crystallization rate (G) has been slightly increased with the increasing volume fraction of filler at 136 °C, the G slightly decreased at 138 °C and there was no trend of G for two higher temperatures. Also, it was not possible to exactly evaluate the influence of the surface treatments. The reason is the most probably uneven (non-homogenous) distribution of nanosilica as revealed thermogravimetric analysis. The crystallization kinetics was evaluated according to the Lauritzen-Hoffmann theory. The morphological part of the study showed that iPP was in ? and ß-structure and spherulites of ? phase were of the type I, II and mixed.
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Automotive plastics with increased scratch resistance
Vida, Mikuláš ; Kučera, František (referee) ; Jančář, Josef (advisor)
The aim of this bachelor thesis was the investigation of changes of mechanical and rheological properties of nanocomposites based on PMMA, where filler was fumed silica of four types (different surface area and producer). The thesis focuses on the theoretical part of the current state of research, preparation and properties of nanocomposites. The solvent method was chosen for the preparation of nanocomposites, where silica was mixed with dissolved PMMA. Tensile mechanical properties were measured below Tg, while viscoelastic response was measured above Tg. Silica had not significant influence on the modulus below Tg, but above Tg (180 °C) both modulus, storage and loss, have increased with increasing silica content and with increasing frequency (0,1–100 Hz). The particle size and surface area of silica in a content of 1 % influenced storage modulus of nanocomposites more with respect to the content of 2 %. For samples containing 1 % showed that the significant role played particle size and surface area of silica. The greatest increase of storage and loss modulus of PMMA was reached for silica M-5 in content 1 %. All type of silica decreased tensile strength and strain with increasing silica content in the same way.
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Polymer nanocomposites with PMMA matrix
Kostková, Jana ; Žídek, Jan (referee) ; Jančář, Josef (advisor)
This bachelor thesis deals with s study of mechanical and viscoelastic properties of nanocomposites with PMMA matrix filled with different types of surface-modified silica, which differed by the specific surface area, surface treatment and particle size. Nanocomposites were prepared by dissolving, where nanofillers were injected into the dissolved matrix. Nanocomposite samples were tested in tensil and viscoelastic properties were determined till the softening point by dynamic-mechanical analysis (DMA). All types of nanofillers had almost no effect on tensile modulus of nanocomposites at room temperature (it was not reduced) one type of silica at a content 2 %, which was also confirmed by the DMA. The temperature DMA measurements showed that samples containing 2 % of silica were generally thermally more stable compared with nanocomposites containing 1 % of silica. Storage modulus of nanocomposites, except two ones, were similar or lower such pure PMMA to temperature 66 C, then the trend reversed. Loss modulus of all samples was one order of magnitude lower then the elastic modulus.
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Polymeric nanocomposites - preparation methods
Černý, Miroslav ; Žídek, Jan (referee) ; Kučera, František (advisor)
Literature search of bachelor thesis was focused to methods of CaCO3 nanoparticles preparation, surface modification and PS/CaCO3 nanocomposites processing. Experimental part was based on two methods of PS/CaCO3 nanocomposites preparation: emulsion and bulk technique of styrene radical polymerization in presence of CaCO3 and by compounding CaCO3 with PS in Brabender mixer at 220 °C. Prepared samples were observed using electron microscope.
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