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Možnosti využití cihelného obrusu v alkalicky aktivovaných systémech
Dzurov, Matej ; Kalina, Lukáš (oponent) ; Šoukal, František (vedoucí práce)
V bakalárskej práci je riešená problematika využitia tehlového prachu, vznikajúceho pri brúsení moderných tehál, ako súčasť alkalicky aktivovaných spojív. Cieľom práce je overenie vlastností tehlového prachu a testovanie mechanických vlastností zmesí s rôznymi pomermi tehlového prachu a granulovanej vysokopecnej trosky, aktivovaných bežne dostupnými hydroxidmi a kombináciami hydroxidov a vodných skiel. Ďalej boli skúmané účinky zvýšenia teploty na vlastnosti pripravených testovacích vzoriek a pozorovanie tvorby uhličitanového výkvetu.
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The effect of polymer microfibers on rheological and mechanical properties of calcium phosphate bone cements
Dzurov, Matej ; Montufar Jimenez, Edgar Benjamin (oponent) ; Vojtová, Lucy (vedoucí práce)
Proposed master’s thesis focuses on mechanical and rheological properties of biodegradable polymer-calcium phosphate bone cement composite reinforced with PCL (poly(-caprolactone)) and PCL-Pluronic polymer microfibers. The theoretical part describes bone structure, evolution of bone cements and structural additives. In the experimental part, synthesis and characterization of PLGA-PEG-PLGA thermosensitive copolymer and -tricalcium phosphate powder is depicted as well as microfibers preparation technique. Copolymer aqueous solution was used to counteract the paste limited injectability, where liquid to powder (L/P) ratio of 0.5 ml/g was used for all of the samples. The two different mixing techniques were used in cement preparation to modulate the sample’s porosity. PCL and PCL-Pluronic fibers used to reinforce the cement were added in the amount of 1, 3 and 5 wt. % to the total mass of cement paste. Prepared pastes were studied at the laboratory (23 °C) and under physiological conditions (37 °C) using dynamical rheological analysis, with the aim to establish workability and setting of the paste. Samples for the rest of the analyses were enabled to set at physiological conditions for the duration of 10 days. Afterward, mechanical parameters like compressive strength, elastic modulus and diametric tensile strength of dried and in some cases hydrated samples were tested. Porosity was established using micro-computed tomography. Scanning electron microscopy was used to study microstructure and fiber incorporation into a ceramic matrix. Presence of fibers was semi-quantitatively studied using Fourier transformed infrared spectroscopy. X-ray diffraction provided data about powder phase transformation and mineralogical aspects of cement. Individual sample performances were evaluated and compared. As a result, addition of either hydrophobic PCL or amphiphilic PCL-Pluronic fibers into polymer-phosphate cement slightly increased compressive strength where PCL-Pluronic modified fibers performed better. Therefore was concluded, that polymer-phosphate bone cement reinforced with microfibers is promising candidate for surgical practice.
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The effect of polymer microfibers on rheological and mechanical properties of calcium phosphate bone cements
Dzurov, Matej ; Montufar Jimenez, Edgar Benjamin (oponent) ; Vojtová, Lucy (vedoucí práce)
Proposed master’s thesis focuses on mechanical and rheological properties of biodegradable polymer-calcium phosphate bone cement composite reinforced with PCL (poly(-caprolactone)) and PCL-Pluronic polymer microfibers. The theoretical part describes bone structure, evolution of bone cements and structural additives. In the experimental part, synthesis and characterization of PLGA-PEG-PLGA thermosensitive copolymer and -tricalcium phosphate powder is depicted as well as microfibers preparation technique. Copolymer aqueous solution was used to counteract the paste limited injectability, where liquid to powder (L/P) ratio of 0.5 ml/g was used for all of the samples. The two different mixing techniques were used in cement preparation to modulate the sample’s porosity. PCL and PCL-Pluronic fibers used to reinforce the cement were added in the amount of 1, 3 and 5 wt. % to the total mass of cement paste. Prepared pastes were studied at the laboratory (23 °C) and under physiological conditions (37 °C) using dynamical rheological analysis, with the aim to establish workability and setting of the paste. Samples for the rest of the analyses were enabled to set at physiological conditions for the duration of 10 days. Afterward, mechanical parameters like compressive strength, elastic modulus and diametric tensile strength of dried and in some cases hydrated samples were tested. Porosity was established using micro-computed tomography. Scanning electron microscopy was used to study microstructure and fiber incorporation into a ceramic matrix. Presence of fibers was semi-quantitatively studied using Fourier transformed infrared spectroscopy. X-ray diffraction provided data about powder phase transformation and mineralogical aspects of cement. Individual sample performances were evaluated and compared. As a result, addition of either hydrophobic PCL or amphiphilic PCL-Pluronic fibers into polymer-phosphate cement slightly increased compressive strength where PCL-Pluronic modified fibers performed better. Therefore was concluded, that polymer-phosphate bone cement reinforced with microfibers is promising candidate for surgical practice.
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Možnosti využití cihelného obrusu v alkalicky aktivovaných systémech
Dzurov, Matej ; Kalina, Lukáš (oponent) ; Šoukal, František (vedoucí práce)
V bakalárskej práci je riešená problematika využitia tehlového prachu, vznikajúceho pri brúsení moderných tehál, ako súčasť alkalicky aktivovaných spojív. Cieľom práce je overenie vlastností tehlového prachu a testovanie mechanických vlastností zmesí s rôznymi pomermi tehlového prachu a granulovanej vysokopecnej trosky, aktivovaných bežne dostupnými hydroxidmi a kombináciami hydroxidov a vodných skiel. Ďalej boli skúmané účinky zvýšenia teploty na vlastnosti pripravených testovacích vzoriek a pozorovanie tvorby uhličitanového výkvetu.
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