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Epoxy resins exposure under severe climatic conditions
Hanačík, Radim ; Rozsívalová, Zdenka (referee) ; Frk, Martin (advisor)
This thesis describes the effects of climatic factors, particularly humidity and temperature on the properties of macromolecular substances, but also others, such as UV radiation, wind, water and oxygen. Furthermore, we introduce the definition and distribution of macromolecular substances. The next section describes the basic properties of dielectric materials. Much of the text is devoted to the description, production, curing, properties and utilization of epoxy resins. The last part deals with climate factors in general terms.
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Ecotoxicological evaulation of polymeric substances
Milatová, Martina ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Polymers or their modifiers may become parts of a wide range of products. After the end of life cycle useful parts of the products are recycled but significant parts still become household waste. It´s therefore desirable not only by law on chemicals and chemical products, but also according to the requirements of European directive REACH, to assess the impact not only chemical but also the additives of all products or products themselves in terms of their impact on the environment. For these purposes it serves ecotoxicity tests, which allow prediction of the influence test compounds in the environment. In this diploma thesis were evaluated polypropylene modifiers, which are commercially produced. Use of ecotoxicity tests were evaluated maleic anhydride and itaconic anhydride effects on the environment. Alternative tests have been used for toxicity and namely Thamnotoxkit FTM the organism Thamnocephalus platyurus and Daphnotokit FTM the organism Daphnia magna. The phytotoxicity test groups were selected toxicity tests: Sinapis alba root growth inhibition toxicity test, Allium cepa L root growth inhibition toxicity test and Semi-chronic toxicity test on Lemna minor L. From marine toxicity tests was performed Acute inhibition test of brine shrimps Artemia salina.
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Increases in water resistance of MDF composites
Másilko, Jiří ; Zmrzlý, Martin (referee) ; Šoukal, František (advisor)
The subject of the diploma thesis is the study of moisture resistance of macrodefect-free (MDF) cements based on calcium-aluminate cement and polyvinylalcohol used as polymer. MDF cements are perspective materials providing unique properties relative to traditional cement pastes with great potential to incoming constructional utilization. But it is known that MDF cements exhibit sensitivity to water, with swelling and reduction of strength. Therefore the work is aimed in monitoring of an organic polymer effect on the moisture resistance of MDF materials and phase changes. Aluminate cement (SECAR 51) and polyvinylalcohol/acetate copolymer have been used for the MDF cement preparation. The moisture resistance of model MDF cement samples was investigated at two different curing conditions: in the moist atmosphere and immersed in water. The influence of composition and individual curing on the properties of model MDF cement samples was observed. The characterization of MDF samples was based especially on test of flexural strength, FT-IR, EDAX and optical microscopy analyses.
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Production of the top of the pressure container
Sobotka, Jiří ; Císařová, Michaela (referee) ; Žák, Ladislav (advisor)
The project developed within the bachelor's degree, proposing a technological parameters of injection molding and tool design for plastic product– segment was suggested from the material PA 6 NOVAMID B30P nature. On the basis of literary study of technological plastic mould injection issues and experiences there was suggested mould injection tool with tunnel inflow, classical extractor was suggested for pressing demoulding. The mould uses standardized components and it corresponds by dimensions with production device ARBURG 420 C 1300-350 (manufacturer ARBURG Gmbh + Co KG, company Loßburg) or ENGEL VICTORY 500/120 Tech (manufacturer Schwertberg, company Schwetberg), with closing force 120 kN or 130 kN. The mould is produced from alloyed tool steel 19 436.9 (POLDI 2002).
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Modern methods of polymers characterisation
Ropek, Lukáš ; Klakurková, Lenka (referee) ; Hutařová, Simona (advisor)
The bachelor thesis consists of an overview of modern methods of polymers testing. The first part deals with historical development, various types and synthesis of polymers. Further work is focused on the structure of polymers, a description of modern sample preparation methods and methods of study the polymers structure. Next, the mechanical properties of polymers and methods of testing the mechanical properties are discussed. Finally, the work is focused on material resistance testing of polymer pipes used in current practice.
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Influence of polymers to reduce dust
Šubrt, Michal ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
The main issue this bachelor thesis deals with the reduction of emit into the enviroment. A specific type of polymer compound from Canadian provenance will be tested for this purpose. The aim of this work will be the identification of positive characteristics of the polymer, and determine to the appropriate method of application. The above mentioned reduction of dust, stabilization of areas after application, possibly reduction of its permeability and increase of its maximum dry density will also by measured.
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Mechanical Properties of Plastics
Suchý, Marek ; Němec, Karel (referee) ; Molliková, Eva (advisor)
This bachelor thesis deals with the plastics in terms of their internal structures. Analyzes the impact of these characteristics on the resulting mechanical properties of materials. Furthermore, examining the external influences significantly on the polymer chain operates. Concludes two basic methods for the detection of mechanical properties - tensile test and 3-point bend tests.
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