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Vinyl prepolymers - methods of preparation and application
Černý, Miroslav ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
The theoretical part of this thesis is focused on bulk radical polymerization of styrene, methylmethacrylate, vinyltoluene and paramethylstyrene. It summarizes actual informations about kinetics and performance possibilities of bulk polymerization. Experimental part deals with polystyrene prepolymers preparation by bulk polymerization. The aim is to find optimal conditions for prepolymers preparation. Prepolymers should be usable for subsequent polymerization nearly up to 100% conversion. Conversion values were gravimetrically determined and molecular weights were obtained by viskosity measurements, which were realized by Ubbelohde viscometer. In the experimental part, there were performed simulations targeted on conversion dependence on time. The purpose was a prediction of monomer conversion at a given time during polymerization. Differences between reality and simulation were low in most of cases and the found form of kinetic behavior calculations provides satisfying results. In the conclusion of this thesis was suggested a new procedure for polystyrene prepolymers preparation.
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Polymeric nanocomposites - preparation methods
Černý, Miroslav ; Žídek, Jan (referee) ; Kučera, František (advisor)
Literature search of bachelor thesis was focused to methods of CaCO3 nanoparticles preparation, surface modification and PS/CaCO3 nanocomposites processing. Experimental part was based on two methods of PS/CaCO3 nanocomposites preparation: emulsion and bulk technique of styrene radical polymerization in presence of CaCO3 and by compounding CaCO3 with PS in Brabender mixer at 220 °C. Prepared samples were observed using electron microscope.
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Effect of initiation on bulk polymerization of styrene
Vojáček, Jakub ; Běťák, Lukáš (referee) ; Kučera, František (advisor)
Bachelor thesis summarizes in the literature part findings on field of the radical initiation of styrene bulk polymerization. Especially polymerization using mono- and bifunctional initiators, further fotoinitiation and thermal initiation of styrene polymerization. The practical part is focused on monitoring the effects of polymerization conditions on monomer conversion, molecular weight, density and viscosity of the prepolymers. Experiments were performed with monofunctional initiator (dibenzoylperoxide), at atmospheric pressure, with polymerization temperature 91 °C, and various concentrations of initiator. Determination of monomer conversion was carried out gravimetrically, the density was determined by titration method and viscosity using the Stokes equation. Molecular weights were then calculated using Kuhn-Mark-Houwink-Sakurad equation.
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Practical approach to bulk polymerization of styrene
Pukančíková, Andrea ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
The diploma thesis deals with radical bulk polymerization of styrene. Recent knowledges about mono- and multifunctional initiators of radical polymerization and coordination polymerization of styrene with metalocene initiators are summarized in theoretical part. Experimental part of diploma thesis is focused on relationship between polymerization conditions and conversion, molecular mass and distribution of molecular mass. Experiments carried out with monofunctional initiators (dibenzoylperoxide, dilauroylperoxide, tert-butylperbenzoate) and with bifunctional initiators (Luperox 101 and Luperox 256). Polymerizations took place at temperatures from 80 to 134 °C, reaction time was from 1 to 24 hours, and pressure was 100 and 500 kPa. Conversion of monomer was determined by gravimetry and infrared spectroscopy. Molecular mass and indexes of polydisperzity were measured by gel permeation chromatography in solutions of polystyrene with tetrahydrofurane at temperature 23 °C.
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Vinyl prepolymers - methods of preparation and application
Černý, Miroslav ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
The theoretical part of this thesis is focused on bulk radical polymerization of styrene, methylmethacrylate, vinyltoluene and paramethylstyrene. It summarizes actual informations about kinetics and performance possibilities of bulk polymerization. Experimental part deals with polystyrene prepolymers preparation by bulk polymerization. The aim is to find optimal conditions for prepolymers preparation. Prepolymers should be usable for subsequent polymerization nearly up to 100% conversion. Conversion values were gravimetrically determined and molecular weights were obtained by viskosity measurements, which were realized by Ubbelohde viscometer. In the experimental part, there were performed simulations targeted on conversion dependence on time. The purpose was a prediction of monomer conversion at a given time during polymerization. Differences between reality and simulation were low in most of cases and the found form of kinetic behavior calculations provides satisfying results. In the conclusion of this thesis was suggested a new procedure for polystyrene prepolymers preparation.
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Practical approach to bulk polymerization of styrene
Pukančíková, Andrea ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
The diploma thesis deals with radical bulk polymerization of styrene. Recent knowledges about mono- and multifunctional initiators of radical polymerization and coordination polymerization of styrene with metalocene initiators are summarized in theoretical part. Experimental part of diploma thesis is focused on relationship between polymerization conditions and conversion, molecular mass and distribution of molecular mass. Experiments carried out with monofunctional initiators (dibenzoylperoxide, dilauroylperoxide, tert-butylperbenzoate) and with bifunctional initiators (Luperox 101 and Luperox 256). Polymerizations took place at temperatures from 80 to 134 °C, reaction time was from 1 to 24 hours, and pressure was 100 and 500 kPa. Conversion of monomer was determined by gravimetry and infrared spectroscopy. Molecular mass and indexes of polydisperzity were measured by gel permeation chromatography in solutions of polystyrene with tetrahydrofurane at temperature 23 °C.
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Effect of initiation on bulk polymerization of styrene
Vojáček, Jakub ; Běťák, Lukáš (referee) ; Kučera, František (advisor)
Bachelor thesis summarizes in the literature part findings on field of the radical initiation of styrene bulk polymerization. Especially polymerization using mono- and bifunctional initiators, further fotoinitiation and thermal initiation of styrene polymerization. The practical part is focused on monitoring the effects of polymerization conditions on monomer conversion, molecular weight, density and viscosity of the prepolymers. Experiments were performed with monofunctional initiator (dibenzoylperoxide), at atmospheric pressure, with polymerization temperature 91 °C, and various concentrations of initiator. Determination of monomer conversion was carried out gravimetrically, the density was determined by titration method and viscosity using the Stokes equation. Molecular weights were then calculated using Kuhn-Mark-Houwink-Sakurad equation.
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Polymeric nanocomposites - preparation methods
Černý, Miroslav ; Žídek, Jan (referee) ; Kučera, František (advisor)
Literature search of bachelor thesis was focused to methods of CaCO3 nanoparticles preparation, surface modification and PS/CaCO3 nanocomposites processing. Experimental part was based on two methods of PS/CaCO3 nanocomposites preparation: emulsion and bulk technique of styrene radical polymerization in presence of CaCO3 and by compounding CaCO3 with PS in Brabender mixer at 220 °C. Prepared samples were observed using electron microscope.
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