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Application of renewable and recyclable raw materials for preparation of new polymers
Horák, Pavel ; Beneš, Hynek (advisor) ; Cajthaml, Tomáš (referee)
This thesis deals with optimalization of flexible polyurethane foam recycling with using of natural polyols based on rape seed oil and fish oil and it explores applications of depolymerized polyol product by formulations of new polyurethane materials. The experiments of depolymerisation showed that both tested natural oil (rape seed oil and fish oil) can be used as effective reagents for polyurethane recycling. Reaction conditions of depolymerisation were optimised with model flexible polyurethane foam and applied on waste foam from real conditions. Gain of depolymerisation is one-faze low viscosity (to 1500 mPa.s) liquid polyol products with content of hydroxyl groups ca 3 mmol/g. These polyols can be used for polymerisation of new materials. First application of recycled polyols was formulation of polyurethane foam systems. Through optimising of formula was prepared low-density semirigid foam containing 100 percentage of recycled polyol. Properties of these foams correspond to commercial foams. To prepare of homogenous cast polyurethane system based on recycled polyols it was necessary to add proper solvent, therefor extent of application has been lowered. On that account the systems were tested for study of polyaddition reaction and for following properties of the material. In these tests, the reactivity...
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Development of progressive polymer anchor material
Žlebek, Tomáš ; Jakubík, Aleš (referee) ; Drochytka, Rostislav (advisor)
The diploma thesis deals with development of a new progressive anchor material on the polymer base. Nowadays, it is effort to utilize secondary raw materials in building industry as much as possible both from an environmental aspects in order to save primary energy sources and the reduction of waste and also due to economic reasons. Therefore, there is an effort to utilize high amount of suitable and appropriately treated secondary raw materials into the anchor materials. The main aim of this work is to develop high quality anchor material characterized by excellent ratio between speed and strength growth, high chemical resistance, thermal resistance and particularly minimal shrinkage. This new material is designed especially for anchoring building structures heavy machines steel barriers and other elements.
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Possibilities of screed application on oily or wet concrete
Holomčík, Zdeněk ; Melichar, Jindřich (referee) ; Drochytka, Rostislav (advisor)
This thesis studiest he track floor system, the interaction of adhesive bonding compound with a underlaying concrete, which will be contaminated by moisture and oil. For such contaminated surface was designed polymer-cement concrete, which were subsequently tested its properties, in order to determine whether it achieves the required strength of 80 MPa uniaxial compressive and whether it can be applied to wet or oily underlaying concrete. From the results we can say that the newly proposed system achieves the specified requirements and could be applied to damp and oily surfaces.
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Development of polymer repairing material
Juřička, Viktor ; Seidlová, Michaela (referee) ; Drochytka, Rostislav (advisor)
Rehabilitation of concrete constructions is important and constantly evolving industry, where development of new, advanced materials contribute to increasing the quailty and effectivness of the remedation process. This work is focused on the development of repairing polymeric material that is able to withstand the conditions of the energy industry and other industrial operations, while effectively utilizing recycled materials. The thesis contains a detailed overview of legislative tests of individual properties and is proposing recipes of appropriate repairing polymeric materials, including a proposal for its application and the pretreatment of input materials.
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Preparation and Properties of Roman Cement
Opravil, Tomáš ; Palou, Martin (referee) ; Škvára, František (referee) ; Havlica, Jaromír (advisor)
The Ph.D. thesis deals with the preparation of highly hydraulic binders based on roman cement. Roman cement (natural cement) is recently not available on the market due to uneconomic production of such a specific binder. On the other hand there is a big lack of information on this hydraulic binder. These results in failure in meeting the basic principle of modern approaches to restoration of historical buildings or monuments made of such kind of materials, which is such, that the materials used for restoration should be compatible with original material. Recognition of the processes of roman cement preparation based on progressive methods of study can provide substantial information for more efficient raw material selection or even for nontraditional utilization, for example for artworks. This work hence is aimed at studying and selection of traditional natural as well as nontraditional raw materials such as clay. This work also studies the preparation of highly hydraulic binders based on roman cement and the kinetics of burning and hydration processes
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Development of innovative composite systems ETICS on the basis of a new generation of secondary raw materials
Kováč, Michal ; Ševčík, Milan (referee) ; Drochytka, Rostislav (advisor)
This master’s thesis applies utilization of alternative raw materials in thermal insulation system of the ETICS of new generation for houses. The theoretical part dealt with the explanation of the ETICS and the selection of suitable raw material for his innovating. In the following practical part were used selected materials to create a new thermal insulation made of straw and binding materials of cement, casein glue, bicomponent fibers and mushroom mycelium. At the end have been applied the variants of base coat of clay and mineral screed on new thermal insulation, from which was selected the optimal variant. From optimal thermal insulation and suitable base coat was conducted proposal of final version of new ETICS.
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New Possibilities to Reduce Raw Material Costs in the Cordierite Production
Sopko, Marek ; Lang, Karel (referee) ; Nevřivová, Lenka (advisor)
The diploma thesis focuses on new possibilities to reduce raw materials costs in production of heat-resistant cordierite ceramics. Cordierite is very often used as furnace wagon lining and for production of blazing utilities for its high resistance against temperature changes. The thesis gives complete overview of cordierite material. It includes description of different production technologies for form-pieces preparation, raw materials for their production and their applications. The goal of performed laboratory measuring in an experimental part was to verify and prove a possibility of reducing raw-material costs in production of cordierite ceramics by using cheaper preferably secondary raw materials.
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Utilization possibilities of industry gypsum and secondary materials containing for preparation of composites
Weiglová, Jana ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
The work studies the possibilities of the utilization of secondary raw materials produced by power industry. It addresses mainly the gypsum by-products and fluidized coal combustion ash. As for the secondary raw materials the content of sulphites is observed and the dependences of their transformation to sulphides via natural oxidation by air oxygen or by addition of adequate oxidant are studied. The work follows with describing the effect of sulphides contained in raw materials on the mechanical properties of composites prepared from several various matrices such as alumina or portland cement, lime or portland clinker. As for pure portland clinker the ability to retard the setting is also observed. The amount of contained sulphites is measured volumetrically via indirect titration of iodine surplus by sodium thiosulphate with the starch size as the indicator.
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