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The influence of conditioning on the mechanical properties of polymers produced by injection molding technology
Neužil, Tomáš ; Řehořek, Lukáš (referee) ; Válka, Libor (advisor)
The aim of the thesis is to determine change of mechanical properties of three types of damp polymeric materials (polyamides) depending on the water content inside material. Before testing, specimens of all three types of materials were placed inside the air conditioning chambers until equilibrium (conditioned) state was reached when the specimens received the maximum possible amount of water from the environment. A total of three conditioning levels were set, representing besides the standard level of conditioning both extreme states like state when the material was fully dried and the state where the material content the largest possible amount of water. With the increasing content of water bound in material, there is a characteristic change in the mechanical properties of the material, such as a decrease in strength and modulus of elasticity and an increase in toughness and ductility. To examine material properties change, tensile and Charpy impact tests were performed, Charpy impact tests were performed for both specimens with and without a notch. Besides changes in mechanical properties, the rate of water absorption was also observed depending on the materials and its filling.
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Studying the possibility of finishes vibration-pressed products
Mrkvica, Lukáš ; Gajdoš, Jan (referee) ; Hela, Rudolf (advisor)
The aim of this work is to describe the current technology of surface processing with a view to improve durability and aesthetic appearance. The work is described in detail features and coatings polymer materials applied, including curing process. In the practical part is a laboratory examination of the influence of sealing and hydrophobicizing additive properties of concrete and also will be tested concrete surface on the absorbency, grindability loss and color retention, slip resistance and resistance to CHRL.
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The study of utilization of raw materials based on glass recyclate
Bajer, Tomáš ; Čermák, Jan (referee) ; Šťastník, Stanislav (advisor)
Presented work deals with the problem of solar glass waste recycling. In theoretical part recent EU regulation regarding waste management is presented. Different ways of PV panels recycling are explained as well as raw materials for glass production are listed. Differences between regular and solar glass is explained. In experimental part different recipes using solar glass waste and polymer binders are presented. Grindability was tested on specimen tiles. Potential of solar glass waste for manufacturing products with acoustic properties was examined.
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Initial study of structure of nanofiber textiles and the creation of its model
Havrlík, M. ; Sveshnikov, Alexey
In this research, the structure of the fabrics was analyzed using an electron scanning microscope Tescan Maia 3. Two sets of the experiments have been carried out. In the first experiment the surface structure of the samples was studied. Photos created by SEM were analyzed using program Atlas and image editor GIMP. In this set of the experiments the initial parameters for the creation of a digital 2D model of a single layer have been determined (fiber size distribution, pore size and curvature of the fibers). In the second set of the experiments cross sections of nanofiber textiles were made in order to study the inner structure of the fabric. This information allows evaluation of the total number of 2D layers in the model and, thus, is very important for future creation of a 3D model of the fabric.
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Book of Abstracts and Programme
Beneš, Hynek
The book of abstracts and program of the 8th Workshop on Green Chemistry and Nanotechnologies in Polymer Chemistry contain contributions in thematically focused scientific sessions covering all frontiers topics in (i) Green Polymer Chemistry: green materials composed of renewable resources, biodegradable materials, low environmental impact routes such as microwave assisted polymerizations, green solvents comprising ionic liquids, polymer waste valorization, etc., and in (ii) Polymer Nanotechnologies: nanomaterials with bio-based and functional nanofillers, nanostructured networks, polymer nanoparticles for sustainable technologies, etc.
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Polymer Elements for a Business Process Management System
Pahuta, Serhii ; Rychlý, Marek (referee) ; Burget, Radek (advisor)
Cílem této diplomové práce je představit a analyzovat technologie Web Components a JBoss BPM Suite. Technologie Web Components dává možnost vytvořit lehkou HTML komponentu s předefinovanou funkčnosti. Vyslédná implementace ukazuje jak tento přístup se používá pro tvorbu sady web komponent, která obsahuje všechny potřebné elementy pro uživatelské konzoli jBPM.
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Computational modeling of diffusion in polymer solutions
Kubečka, Jakub ; Košovan, Peter (advisor) ; Šachl, Radek (referee)
We performed coarse-grained molecular dynamics simulations of fully dissociated polyelectrolytes in the presence of monovalent and multivalent counterions and charged oligomers. The dynamics of these systems has been studied to follow internal dynamics of polyelectrolyte and counterions. The dynamics is presented via the mean square displacement which we obtain from the simulation trajectory and, moreover, via curves of Fluorescence Correlation Spectroscopy (FCS) obtained also from the simulation trajectory. FCS is an experimental technique which can be used to study condensation of counterions on polyelectrolytes. Therefore, we analyze the FCS curves and investigate applicability of various analytical models to fit these FCS curves. The aim of this work is a discussion about the fitting of the FCS curves and presentation of our observations for dynamics of counterions during condensation on the polyelectrolyte.
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Self-Assembly in Mixture of Surfactants and Stimuli-Responsive Polymers with Complex Architecture
Bogomolova, Anna ; Filippov, Sergej (advisor) ; Štěpánek, Miroslav (referee) ; Hanyková, Lenka (referee)
Title: Self-assembly in mixture of surfactants and stimuli-responsive polymers with complex architecture Author: Anna Bogomolova Department: Physical and Macromolecular Chemistry Supervisor: PhD. Sergey K. Filippov, IMC AS CR, v.v.i. Supervisor's e-mail address: filippov@imc.cas.cz Abstract: The issue of construction of complex multi-block copolymers is currently one of the most researched areas. It became a logic consequence of the continuous development in polymer chemistry. Nowadays, a great interest is attracted to multi- responsive block copolymers. As a rule, they consist of hydrophilic, hydrophobic and responsive blocks. That responsive block can be either thermo-sensitive or pH-sensitive as well as sensitive to some other external stimuli. In the present work, we will try to cover topic of stimuli-responsive block copolymers and their interactions with different types of surfactants. Understanding of polymer/surfactant interactions can be a crucial step for future modeling of drug/polymer or protein(DNA)/surfactant interactions. There is a great interest in the investigation of polymer-surfactant interactions. However, while the homopolymer-surfactant interactions are characterized well enough, the same interactions for block copolymers are poorly described. The main development in the latter topic...
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Measurement and evaluation of elongational viscosity of selected biomaterials
Šustková, Hana ; Krakovský, Ivan (advisor) ; Fortelný, Ivan (referee)
Measurement and evaluation of elongational viscosity of selected biomaterials Bachelor thesis abstract Hana Šustková 20.5.2011 This thesis analyzes the elongational viscosity of the biomaterials. The basic concepts related to the issue of measurement of shear and elongational viscosity of melts in particular focusing on the SER rheometer, which was used in the experiment, were presented. With SER rheometer elongational viscosity of BioFlex samples of BioFlex, PA6 and their mixtures at temperatures of 225o C and 235o C for ten Hencky different strain rates from 0.1 to 10 s−1 were studied. In the experiment rectangular specimens prepared for different content of Bioflex and Polyamide PA6 were used. Based on the data presented in this thesis some features of the internal structure of used bio- material, and its possible practical applications, further and qualitative changes in its properties in the mixture were described. It was shown that the linear viscoelastic response of BioFlex is two orders of magnitude below in comparison to the response of PA6 and in the temperature range the linear viscoelastic response does not change. It is shown that in mixtures with BioFlex and PA6 the BioFlex shows a signifi- cant proportion of the linear viscosity range - and at low concentrations of BioFlex in comparison to PA6...
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