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Photopolymerization
Kučera, Vladimír ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
The bachelor thesis deals with the photochemistry of macromolecular substances, especially with photopolymerization and photocrosslinking reactions. In the theoretical section there is at first a summary of the current knowledge from the area of the general photochemistry and principles of photochemical reactions which are also applied in photopolymerization. There are also both types of photopolymerization analysed – cationic and free-radical, photocrosslinking reactions and photopolymerization applications. In the experimental part, the testing of two fotopolymerization systems was performed. In both of them, styrene was used as a monomer. In one case benzoin was used as a photoinitiator, in the second one there was benzoin ethyl ether used. Furthermore, the photoinitiation ability of these two photoinitiators was compared at the base of conversion and molecular weight of products that were synthetized at different concentrations of photoinitiators and different time periods of irradiation of the mercury lamp.
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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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Preparation and Characterization of Magnetic Carriers from Hypercrosslinked Polystyrene Microspheres and their Application in a Biosensor.
Šálek, Petr ; Šňupárek, Jaromír (referee) ; Šafařík,, Ivo (referee) ; Horák, Daniel (advisor)
With the aim to develop and characterize a functionalized highly magnetic polymer carrier of micrometer size and of a narrow particle size distribution that will be suitable for biological application, hypercrosslinked microspheres were prepared. Simultaneously, the relation between structure and properties of product was observed. Condition of dispersion polymerization were optimized to obtain starting monodisperse poly(styrene-co-divinylbenzene) [P(St-DVB)] microspheres. The P(St-DVB) microspheres of different degree of crosslinking were prepared and effect of some polymerization parameters such as type of solvent, initiator, concentration and mode of DVB addition on morphology, size and particle size distribution were investigated. The starting microspheres were hypercrosslinked to obtain microporous inner structure. Hyperosslinked particles had very large specific surface area (> 1000 m2/g) and a high content of micropores (ca. 0.6 ml/g). First, P(St-DVB) microspheres were chloromethylated using three different chloromethylation agents to regulate their porous properties. Hypercrosslinking was achieved by the addition of stannic chloride as a catalyst and by increasing a temperature. The hypercrosslinked microspheres were then functionalized with sulfo- or aminogroups. The functional groups captured precipitated iron oxide inside the porous structure of the microspheres and also served as a reactive site for intended immobilization of the protein. A solution of ferrous and ferric chloride was imbibed under vacuum into the porous structure and the iron oxide was precipitated by an aqueous ammonia solution. Finally, the magnetic functionalized hypercrosslinked micropsheres were integrated into a biosensor for qualitative detection of ovalbumin.
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Capillary monolithic columns based on copolymer of styrene, divinylbenzene and methacrylic acid and their application for separations of small molecules.
Musilová, Adéla
This work is focused on the preparation and characterization of capillary monolithic columns based on a copolymer of styrene, divinylbenzene and methacrylic acid for the chromatographic separation of small molecules. The capillary monolithic columns were prepared in the quartz capillaries by one-step radical copolymerization reaction of monomers of styrene, divinylbenzene and methacrylic acid in the presence of toluene and isooctane as porogenic solvents and azobisisobutyronitrile as an initiator. The effect of incorporation of methacrylic acid into the polymerization mixture on the separation behavior and efficiency in reversed phase capillary liquid chromatography (CLC) and capillary liquid electrochromatography (CEC) was studied using a test mixture of compounds containing thiourea, phenol, aniline, benzene, toluene, ethylbenzene, propylbenzene and butylbenzene. The Walters test for reversed stationary phases was employed to evaluate the hydrophobicity of the prepared columns. Based on the calculated value of hydrophobicity index of 10.76, the prepared monolithic columns can be classified as very hydrophobic. Excellent repeatability of measurements in CLC mode and very good repeatability of the monolithic column preparation were achieved. The effect of polymerization time on the chromatographic...
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Capillary monolithic columns based on copolymer of styrene, divinylbenzene and methacrylic acid and their application for separations of small molecules.
Musilová, Adéla ; Coufal, Pavel (advisor) ; Čabala, Radomír (referee) ; Sýkora, David (referee)
This work is focused on the preparation and characterization of capillary monolithic columns based on a copolymer of styrene, divinylbenzene and methacrylic acid for the chromatographic separation of small molecules. The capillary monolithic columns were prepared in the quartz capillaries by one-step radical copolymerization reaction of monomers of styrene, divinylbenzene and methacrylic acid in the presence of toluene and isooctane as porogenic solvents and azobisisobutyronitrile as an initiator. The effect of incorporation of methacrylic acid into the polymerization mixture on the separation behavior and efficiency in reversed phase capillary liquid chromatography (CLC) and capillary liquid electrochromatography (CEC) was studied using a test mixture of compounds containing thiourea, phenol, aniline, benzene, toluene, ethylbenzene, propylbenzene and butylbenzene. The Walters test for reversed stationary phases was employed to evaluate the hydrophobicity of the prepared columns. Based on the calculated value of hydrophobicity index of 10.76, the prepared monolithic columns can be classified as very hydrophobic. Excellent repeatability of measurements in CLC mode and very good repeatability of the monolithic column preparation were achieved. The effect of polymerization time on the chromatographic...
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Preparation and Characterization of Magnetic Carriers from Hypercrosslinked Polystyrene Microspheres and their Application in a Biosensor.
Šálek, Petr ; Šňupárek, Jaromír (referee) ; Šafařík,, Ivo (referee) ; Horák, Daniel (advisor)
With the aim to develop and characterize a functionalized highly magnetic polymer carrier of micrometer size and of a narrow particle size distribution that will be suitable for biological application, hypercrosslinked microspheres were prepared. Simultaneously, the relation between structure and properties of product was observed. Condition of dispersion polymerization were optimized to obtain starting monodisperse poly(styrene-co-divinylbenzene) [P(St-DVB)] microspheres. The P(St-DVB) microspheres of different degree of crosslinking were prepared and effect of some polymerization parameters such as type of solvent, initiator, concentration and mode of DVB addition on morphology, size and particle size distribution were investigated. The starting microspheres were hypercrosslinked to obtain microporous inner structure. Hyperosslinked particles had very large specific surface area (> 1000 m2/g) and a high content of micropores (ca. 0.6 ml/g). First, P(St-DVB) microspheres were chloromethylated using three different chloromethylation agents to regulate their porous properties. Hypercrosslinking was achieved by the addition of stannic chloride as a catalyst and by increasing a temperature. The hypercrosslinked microspheres were then functionalized with sulfo- or aminogroups. The functional groups captured precipitated iron oxide inside the porous structure of the microspheres and also served as a reactive site for intended immobilization of the protein. A solution of ferrous and ferric chloride was imbibed under vacuum into the porous structure and the iron oxide was precipitated by an aqueous ammonia solution. Finally, the magnetic functionalized hypercrosslinked micropsheres were integrated into a biosensor for qualitative detection of ovalbumin.
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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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Photopolymerization
Kučera, Vladimír ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
The bachelor thesis deals with the photochemistry of macromolecular substances, especially with photopolymerization and photocrosslinking reactions. In the theoretical section there is at first a summary of the current knowledge from the area of the general photochemistry and principles of photochemical reactions which are also applied in photopolymerization. There are also both types of photopolymerization analysed – cationic and free-radical, photocrosslinking reactions and photopolymerization applications. In the experimental part, the testing of two fotopolymerization systems was performed. In both of them, styrene was used as a monomer. In one case benzoin was used as a photoinitiator, in the second one there was benzoin ethyl ether used. Furthermore, the photoinitiation ability of these two photoinitiators was compared at the base of conversion and molecular weight of products that were synthetized at different concentrations of photoinitiators and different time periods of irradiation of the mercury lamp.
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