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Templating as a new method of creating and modifying the porous texture of polyacetylene networks
Sokol, Jiří ; Sedláček, Jan (advisor) ; Balcar, Hynek (referee)
A new method of introducing permanent micropores into hyper-cross-linked polyacetylene networks has been developed. The method used a combination of polyacetylene chemistry and Schiff base chemistry. Through the coordination chain-growth polymerization of monomers with polymerizable ethynyl groups, a wide series of homopolymer and copolymer networks with rigid polyene main chains interconnected by arylene links was prepared. The networks carried substituents of the predominantly aromatic Schiff-base-type in the pendant groups. With increasing content and volume of these substituents the specific surface area of the networks decreased. The networks with a high content of Schiff-base-type substituents were non-porous. The prepared networks were subsequently hydrolyzed under the conditions optimized in this diploma thesis. The hydrolysis led to a highly efficient cleavage of the Schiff base methanimine linkages and to the removal of the cleaved low molecular weight aromatic amine and aldehyde segments from the networks. In this way, new functional groups were generated in the networks, either CH=O or NH2. The hydrolytic modification had a fundamental effect on the texture parameters of the networks. The modification of the originally microporous networks mostly led to an increase in the specific...
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Marketing strategy of company Falco
Hamrlová, Lucie ; Postler, Milan (advisor) ; Sokol, Jiří (referee)
The topic of my bachelor thesis is designing a marketing strategy for a company Falco, which is concerned with making cans with dog and cat food. The main goal is to assess their current marketing strategy and conseqently to propose changes, which should be helpful under the current circumstances. These changes are based on results of my own questionnaire survey. In the theoretical part of this thesis are main principles of marketing and its characteristics are discussed, and these are then used as a basis for the practical part. The practical part is mostly concerned with the company itself, its establishment and its strengths and weaknesses, where were defined using the SWOT analysis. This part contains PEST analysis as well. Furthermore the questionnaire survey is also included here, whose results were used to propose changes in order to improve the marketing strategy.
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Polycyclotrimerization of alkynes with internal ethynyl groups
Sokol, Jiří ; Sedláček, Jan (advisor) ; Balcar, Hynek (referee)
The diynes of both aliphatic and aromatic types comprising either (i) two internal ethynyl groups or (ii) one internal and one terminal ethynyl group in the molecule were revealed as appropriate monomers for the Co2(CO)8 catalyzed polycyclotrimerization yielding high-molecular-weight products. The polycyclotrimerization of aliphatic diynes with a short (CH2)2 link between ethynyl groups and the polycyclotrimerization of aromatic diynes provided polycyclotrimer networks with tri-, tetra-, penta- and hexasubstituted benzene segments. The polycyclotrimers of aliphatic diynes did not exhibit microporous texture. On the other side, the polycyclotrimers of aromatic monomers were mostly microporous with specific surface area up to SBET = 499 m2 /g. The nitrogen desorption isotherms on microporous polycyclotrimers exhibited a significant unclosed hysteresis. This indicated that the penetration of nitrogen into polymers was accompanied by formation of temporary pores or opening permanent pores of worse accessibility.
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