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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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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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Synthesis and polymerization of substituted derivatives of caprolactone
Vrbata, David ; Zedník, Jiří (advisor) ; Smrček, Stanislav (referee)
Copper (I) mediated Huisgen 1,3 dipolar cycloaddition of 4-(piperidine-1-yl)-N-(prop-1-yne- 3-yl)-1,8-naphtalimide (PN) to poly(αN3εCL-co-εCL) of three different molar ratio of αN3εCL was performed. Reaction was succesfull for poly(αN3εCL-co-εCL) with molar fraction of αN3εCL f = 0,22. No degradation of substituted PCL was observed during the synthetic path, therefore the PN molecule is suitable for click coupling to well defined polyester. New aliphatic polyester based on polycaprolactone was synthesized and characterized by means of 1 HNMR spectra and Gel permeation chromatography calibrated with polystyrene standards. The spectra of other two copolymers coupled with PN were not measured due to their low solubility in common organic solvents. Keywords: living polymerization, α-chloro-ε-caprolactone, click reaction
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Synthesis and polymerization of substituted derivatives of caprolactone
Vrbata, David ; Zedník, Jiří (advisor) ; Smrček, Stanislav (referee)
Copper (I) mediated Huisgen 1,3 dipolar cycloaddition of 4-(piperidine-1-yl)-N-(prop-1-yne- 3-yl)-1,8-naphtalimide (PN) to poly(αN3εCL-co-εCL) of three different molar ratio of αN3εCL was performed. Reaction was succesfull for poly(αN3εCL-co-εCL) with molar fraction of αN3εCL f = 0,22. No degradation of substituted PCL was observed during the synthetic path, therefore the PN molecule is suitable for click coupling to well defined polyester. New aliphatic polyester based on polycaprolactone was synthesized and characterized by means of 1 HNMR spectra and Gel permeation chromatography calibrated with polystyrene standards. The spectra of other two copolymers coupled with PN were not measured due to their low solubility in common organic solvents. Keywords: living polymerization, α-chloro-ε-caprolactone, click reaction
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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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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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