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Hybrid Blends of Recycled Plastics
Černý, Miroslav ; Lehocký, Marián (referee) ; Balgová,, Vendula (referee) ; Jančář, Josef (advisor)
Work describes the relationship between structure and mechanical properties in case of hybrid mixtures. They are composed from polyurethane matrices (eventually polyurethane-urea or polyurethane-inorganic filler mixtures), different rubber fractions as filler and eventually reinforcement made from PET monofilaments. Mechanical behaviour was studied by tensile testing. Studied mechanical properties include tensile modulus, ultimate strength and strain and also specific energy need neccessary for ultimate strength achievement. Prepared materials are naturally porous. Therefore their mechanical behaviour has to be described generally for porous composites. The porosity occurence means, that it is difficult to describe them by models valid for mechanical behaviour (mainly elastic modulus) of nonporous composites. Models are also based on idealized structures on microscopic level. In case of porous composites, it is very difficult to create any idealized structure. The structure is changed with modifications of composition (change of components or their rates). These conditions have lead to utilizing of different approach how to describe the relationship between structure and mentioned mechanical properties. The chosen approach comes from knewledge about structural parametres coming from porosity. Structural parameters describe the structure on macroscopic level. They include interspace volume (volume lying between filler particles), interspace filling (how the matrix fills the interspace volume) and matrix volume fraction. Proposed parameters are used in relations, where they are fitted by exponents to interlay values of chosen mechanical properties for composites containing discrete matrix and filler. Found exponents are then described by properties of matrices to obtain relations describing properties of filled porous materials. Very similar approach was chosen for description in the case of reinforced composites. Proposed relation are potentially valid for materials containing binding matrix, infinity count of fillers and one kind of reinforcement.
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Use of composite materials in automotive industry
Bárta, Miroslav ; Müller, Miroslav (advisor) ; Valášek, Petr (referee)
This work deals with the use of composite materials in the automotive industry. The first part is a familiar historical overview of the evolution of materials explaining the definition of terms, the basic distribution of composite materials and processing methods and technology composite production. The second part focuses on the application of composite materials in the automotive industry at the moment.
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Research and optimization of liquid metals with emphasis on application in sphere of renovation
Hynek, Pavel ; Müller, Miroslav (advisor) ; Hrabě, Petr (referee)
The aim of the master thesis is to research liquid metals, or research on the influence of the selected particulate filler to selected mechanical properties that characterize the use of liquid metals for renovation of machine parts or assembly parts, two-component reactive adhesives based on epoxy resin, with a partial aim to assess and select the optimal amount added . In this master thesis are interpreted measured values for each of the fillers that are in discussion compares the results of other research papers. In the last part of master thesis is done techno-economic evaluation.
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Analysis of filler types onto the wood plastics composites
Blaha, Lukáš ; Pospíšil,, Ladislav (referee) ; Vaněrek, Jan (advisor)
Wood polymer composite (WPC) is a material that combines the wood material and the thermoplastic matrix. As filler to be used as wood flour and thermoplastic matrix will be used in primary or recycled polypropylene. WPC will be made by injection molding. The aim of the thesis is to find the optimal ratio between primary and recycled polymer in which the result will be the best physical and mechanical properties.
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Modification of epoxy resin effecting ductility of wood bonds
Hudečková, Petra ; Drochytka, Rostislav (referee) ; Vaněrek, Jan (advisor)
This bachelor thesis is focus on a jointing process of wood parts, the basic kinds of adhesives that are used for wood constructions, and also deals with an important demands on a bonded wood joint. Then there is briefly described an issue of fracture toughness and the ways of epoxy adhesives filling, primarily filling with the rubber, the thermoplastics and other fillers. In the experimental part the reinforcing of epoxy matrix with the different quantity of rubber was carried out. The mixture was prepared by an ultrasound homogenizer. Firstly, the tensile strength test with epoxy samples was carried out. Secondly, the Young modulus was calculated and in the last part the fracture surface was analyzed with the scanning electron microscope.
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Study of the properties of fillers to the composites requiring high temperature resistance
Vovesný, Václav ; Gross,, Tomáš (referee) ; Bydžovský, Jiří (advisor)
The diploma thesis is focused on the behaviour of natural and synthetic aggregates and their behaviour in polymer – cement composites, while being exposed to high temperature. The processes, happening in aggregates and mortar under the thermal load, were described in the theoretical part of the thesis same as the testing of heat effects on the aggregates and mortar. Further, the influence of high temperature on each component of concrete was described, followed by the suggestion of the appropriate components for concrete exposed to high temperature. Various aggregates were tested in the experimental part of the thesis. The basic physical and mechanical properties of aggregates were examined same as their mineralogical composition with using XRD, DTA and SEM methods. At the mortar, the influence of high temperature on the concrete density, compressive strength and tensile strength was defined. The gained knowledge was evaluated in the final part of the thesis
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Development of a thermal insulating material designed for use with high temperature
Dokoupil, Martin ; Frajt, Daniel (referee) ; Drochytka, Rostislav (advisor)
The work deals with the development of a new thermal insulation material that contains a secondary raw materials or waste. It is an insulating material with the requirement of resistance to high temperatures - 200 ° C and 500 ° C. Type of material is determined by the way of reducing density - direct and indirect. Direct is achieved by adding lightweight aggregates, indirect is achieved by gas evolution through chemical reaction and the subsequent incorporation of gas into the structure of the material. This thesis is part of the MPO TIP č. FR-TI 2/340 project.
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Development of Resistant Coating Systems Based on Polymer Binders
Voráčová, Veronika ; Vyhnánek, Miroslav (referee) ; Petránek, Vít (advisor)
The aim of the thesis is to propose the use of waste materials as filler for the selected coating systems used for chemical protection of concrete surfaces.The used filler could not affect the existing binder of the coating system. Research was conducted using two materials N141 and N 121. The waste material was chosen by his chemical and physical properties. Between suitable materials belongs slag, fly ash, foundry sand and glass waste. The selection based on Lena Chemical s.r.o companies request was selected glass waste. The practical part includes examination as fillers, and the corresponding tests for coating systems with pre-used filler. Finally, the assessment of the suitability of the materials used.
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Heat insulating moulded refractory concretes
Bednárek, Jan ; Bartoníčková, Eva (referee) ; Šoukal, František (advisor)
The thesis deals with the possibility of specific weight lowering of kaolin suspensions using air-entraining agents. These agents are usually used as concrete admixtures. The goal of the thesis is to verify an alternative possibility of creating porous structure in kaolin suspensions in order to prepare heat insulating moulded refractory concretes without using lightweight fillers. The effect of several air-entraining agents was compared, after that the dosage of agent and mixing conditions were optimized. The stabilization of prepared foams and practical application of selected agents were also part of the thesis.
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