National Repository of Grey Literature 3 records found  Search took 0.01 seconds. 
Catalytic Enantioselective Desymmetrization of meso-Epoxides
Malatinec, Štefan ; Kotora, Martin (advisor) ; Baszczyňski, Ondřej (referee)
Catalytic enantioselective desymmetrization of meso-epoxides is widely used in many areas of chemistry. Such process is usually catalyzed by a transition metal complex with a chiral ligand. Recently, a synthesis of an analogue of Bolm's 2,2'-bipyridine ligand was developed and its combination with metal salts were tested in various reactions. In this master's thesis, a catalytic system composed of Sc(OTf)3/Bolm's ligand analogue was studied in alcoholysis and aminolysis of the meso- epoxides. The reaction has been extended to a broad range of alcohols providing 1,2-diol monoethers in excellent enantioselectivity up to 99% ee. The aminolysis of meso-epoxides has been optimized, as well. The catalyst loading could be lowered to 1 mol% with only marginal effects on the enantioselectivity. Key words: epoxides, enantioselective catalysis, chiral ligands.
A comparison of different types of epoxy adhesives
Mihulka, Jan ; Žák, Ladislav (referee) ; Kubíček, Jaroslav (advisor)
This thesis is focused on a bonding technology. The first part describes the theory of the bonding and it is discussed the main areas of this technology. The experimental part deals with the comparison of four two-component epoxy adhesives in terms of shear strength. For the experiment it had been selected adhesives: Bison Epoxy Universal, Pattex Repair Epoxy Ultra Strong 5 min, Ergo 7430 and Letoxit LH 232. After performing the experiment, it was shown that Bison Epoxy Universal and Pattex Repair Epoxy Ultra Strong 5 min achieved the strengths stated in the datasheet. The strengths of Ergo 7430 and Letoxit LH 232 adhesives was lower than stated in their technological products, thefore, did not meet our expectations. The reason for not achieving the declared strength was probably poor dosing or insufficient mixing of ingredients.
Bonding of composite materials
Drkoš, Jan ; Molliková, Eva (referee) ; Němec, Karel (advisor)
The thesis deals with the analysis of the bonding of composite materials and the subsequent selection of adhesive for the specified glued joint consisting of two pieces of carbon composites. The thesis summarizes the theory of composite materials and then explains in more detail the theory of bonding together with the subsequent testing of glued joint. Another part of the thesis focuses on the market research in the field of available and suitable adhesives and the subsequent selection of the new adhesive for the glued joint, on which the epoxy adhesive was previously used. In this part, glued joints with two pre-selected adhesives were tested and then a conclusion was drawn for the selection of the most suitable adhesive.

Interested in being notified about new results for this query?
Subscribe to the RSS feed.