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Glass-ceramic composite biomaterials
Žaludek, Jakub ; Hadraba, Hynek (referee) ; Drdlík, Daniel (advisor)
The bachelor thesis is focused on the preparation of bioglass 45S5 and composites containing bioglass 45S5 and alumina or zirconia fibres in amount of 1, 3 and 5 wt% by slip-casting method from aqueous and 2-propanolic suspensions. The materials prepared were characterised in term their porosity, relative density, high temperature dilatometry, X-ray diffraction analysis, microstructure and hardness. The slip-casting method produced porous samples which is promising result for a possible biomedical application. The high temperature dilatometry identified three stages of the sintering process and a shrinkage of ~40% of the bioglass-based materials was measured. The crystalline phase of Na2Ca2Si3O9 was created at the sintering temperature of 1050°C but the dissolution of Al2O3 or ZrO2 fibres into the bioglass matrix was not confirmed using the X-ray diffraction analysis. It was found that the hardness of the samples decreased with the amount of the fibres in the materials which was caused by their increasing porosity and large clusters of fibres.
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Electrospinning of bioglass and glass-ceramic fibers
Kozáková, Zdenka ; Šťastná, Eva (referee) ; Částková, Klára (advisor)
Bachelor thesis is focused on the preparation of fibers based on bioglass and glass ceramics. The theoretical part of the work summarizes the division and description of biomaterials and their use in biomedical applications. The main part of the work deals with the preparation of bioglass with a focus on the preparation by electrospinning. Experimental part is focused on the preparation of fibers based on bioglass by electrospinning. Different types of bioglass precursors were studied and their spinnability, morphology and bioactivity of the prepared fibers were assessed. The fibers were analyzed by scanning electron microscopy and interactions in simulated body fluid. Fibers prepared from bioglass 45S5 and polyvinylalcohol precursor were evaluated as promising for biomedical applications.
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Preparation and properties of Bioglass based foam materials
Nedbalová, Radka ; Hadraba, Hynek (referee) ; Dlouhý, Ivo (advisor)
The work deals with the preparation and mechanical properties of coated Bioglass® 45S5 based foam materials with open porosity. The samples have been fabricated applying the replication method with use of polyurethane foam. Furthermore, these samples were coated in order to increase the strength characteristics and crack resistance. Polyvinylalcohol and PVA with cellulose microfibrils have been used as coating. Besides microstructural parameters of investigated materials using the SEM images strength characteristics in compression and in tension were also quantified.
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Bioactive ceramic foams – processing, properties testing and applications
Motyka, Jan ; Hadraba, Hynek (referee) ; Řehořek, Lukáš (advisor)
Porous materials for tissue engineering are novel group of materials. They provide some unique properties, namely bioactivity, biodegradability and osteoconductivity. Ceramics porous structure for bone substitutes have considerable potential for applications in medical surgery. But they have poor mechanical properties. Hence they are used for low bearing applications. Those are the reasons for extensive investigation of these materials, mainly in the last few years. Lots of production procedures exist, which leads to production of foams with various shapes and properties.
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Study of bioceramic composite based on hydroxyapatite and bioglass
Virágová, Eliška ; Hadraba, Hynek (referee) ; Drdlík, Daniel (advisor)
This bachelor thesis is focused on the bioceramic composite materials based on hydroxyapatite (HAp) and bioglass (BG). The wet shaping method, i.e. electrophoretic deposition (EPD), was chosen for the preparation of these materials. The methodology of preparation and its influence on kinetics, relative density and pore distribution in the prepared composites was evaluated. The sintering process of the prepared composites was studied using high temperature dilatometry with subsequent evaluation of their microstructural and mechanical features. It was found that EPD is an applicable method for successful preparation of the particle composites. The microstructural quality of particle composites was affected mainly by the electrical conductivity of the suspension. It was found during the study of EPD kinetics that the highest deposition rate was achieved in the suspension with the lowest electrical conductivity. Increasing amount of BG in HAp caused increase of the relative density and pore diameter whereas the volume of pores decreased. High temperature dilatometry showed a decrease of relative shrinkage, which was evident with increasing HAp amount in the structure. Observation of the microstructure revealed a crystalline structure of BG and an open porosity of HAp, which is desired for biocompatible materials. The phase composition of the materials was determined by X-ray diffraction analysis. In case of the mechanical properties it was found an increase of the hardness and Young’s modulus of elasticity with the increasing amount of BG in bioceramic composites. Based on the obtained results the suitable process and material composition for the planned preparation of the functionally graded material were identified.
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Study of bioceramic composite based on hydroxyapatite and bioglass
Virágová, Eliška ; Hadraba, Hynek (referee) ; Drdlík, Daniel (advisor)
This bachelor thesis is focused on the bioceramic composite materials based on hydroxyapatite (HAp) and bioglass (BG). The wet shaping method, i.e. electrophoretic deposition (EPD), was chosen for the preparation of these materials. The methodology of preparation and its influence on kinetics, relative density and pore distribution in the prepared composites was evaluated. The sintering process of the prepared composites was studied using high temperature dilatometry with subsequent evaluation of their microstructural and mechanical features. It was found that EPD is an applicable method for successful preparation of the particle composites. The microstructural quality of particle composites was affected mainly by the electrical conductivity of the suspension. It was found during the study of EPD kinetics that the highest deposition rate was achieved in the suspension with the lowest electrical conductivity. Increasing amount of BG in HAp caused increase of the relative density and pore diameter whereas the volume of pores decreased. High temperature dilatometry showed a decrease of relative shrinkage, which was evident with increasing HAp amount in the structure. Observation of the microstructure revealed a crystalline structure of BG and an open porosity of HAp, which is desired for biocompatible materials. The phase composition of the materials was determined by X-ray diffraction analysis. In case of the mechanical properties it was found an increase of the hardness and Young’s modulus of elasticity with the increasing amount of BG in bioceramic composites. Based on the obtained results the suitable process and material composition for the planned preparation of the functionally graded material were identified.
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Electrospinning of bioglass and glass-ceramic fibers
Kozáková, Zdenka ; Šťastná, Eva (referee) ; Částková, Klára (advisor)
Bachelor thesis is focused on the preparation of fibers based on bioglass and glass ceramics. The theoretical part of the work summarizes the division and description of biomaterials and their use in biomedical applications. The main part of the work deals with the preparation of bioglass with a focus on the preparation by electrospinning. Experimental part is focused on the preparation of fibers based on bioglass by electrospinning. Different types of bioglass precursors were studied and their spinnability, morphology and bioactivity of the prepared fibers were assessed. The fibers were analyzed by scanning electron microscopy and interactions in simulated body fluid. Fibers prepared from bioglass 45S5 and polyvinylalcohol precursor were evaluated as promising for biomedical applications.
|
|
|
Glass-ceramic composite biomaterials
Žaludek, Jakub ; Hadraba, Hynek (referee) ; Drdlík, Daniel (advisor)
The bachelor thesis is focused on the preparation of bioglass 45S5 and composites containing bioglass 45S5 and alumina or zirconia fibres in amount of 1, 3 and 5 wt% by slip-casting method from aqueous and 2-propanolic suspensions. The materials prepared were characterised in term their porosity, relative density, high temperature dilatometry, X-ray diffraction analysis, microstructure and hardness. The slip-casting method produced porous samples which is promising result for a possible biomedical application. The high temperature dilatometry identified three stages of the sintering process and a shrinkage of ~40% of the bioglass-based materials was measured. The crystalline phase of Na2Ca2Si3O9 was created at the sintering temperature of 1050°C but the dissolution of Al2O3 or ZrO2 fibres into the bioglass matrix was not confirmed using the X-ray diffraction analysis. It was found that the hardness of the samples decreased with the amount of the fibres in the materials which was caused by their increasing porosity and large clusters of fibres.
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|
|
Preparation and properties of Bioglass based foam materials
Nedbalová, Radka ; Hadraba, Hynek (referee) ; Dlouhý, Ivo (advisor)
The work deals with the preparation and mechanical properties of coated Bioglass® 45S5 based foam materials with open porosity. The samples have been fabricated applying the replication method with use of polyurethane foam. Furthermore, these samples were coated in order to increase the strength characteristics and crack resistance. Polyvinylalcohol and PVA with cellulose microfibrils have been used as coating. Besides microstructural parameters of investigated materials using the SEM images strength characteristics in compression and in tension were also quantified.
|
|
|
Bioactive ceramic foams – processing, properties testing and applications
Motyka, Jan ; Hadraba, Hynek (referee) ; Řehořek, Lukáš (advisor)
Porous materials for tissue engineering are novel group of materials. They provide some unique properties, namely bioactivity, biodegradability and osteoconductivity. Ceramics porous structure for bone substitutes have considerable potential for applications in medical surgery. But they have poor mechanical properties. Hence they are used for low bearing applications. Those are the reasons for extensive investigation of these materials, mainly in the last few years. Lots of production procedures exist, which leads to production of foams with various shapes and properties.
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