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Design of chemically resistant coatings using secondary raw materials and hazardous waste
Stodolovská, Šárka ; Jakubík, Aleš (referee) ; Drochytka, Rostislav (advisor)
On the basis of theoretical knowledge gained from Czech and foreign technical literature, two types of coatings using fillers based on secondary raw materials, including hazardous waste, is designed and experimentally verified. The expected use of the proposed coating systems, both PREMIUM and ECOLOGY, is the protection of building structures that are permanently stressed by increased chemical stress. When designing the PREMIUM coating material, emphasis is primarily focused on chemical resistance and functional parameters, and the ecological performance of the raw materials used is monitored primarily with the ECOLOGY coating material. In both cases, it is important to maintain a favorable price / value ratio.
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Isolation of lignin from grape seeds and its application as filler for polyhydroxyalkanoates (PHA)
Vostrejš, Pavel ; Vítová, Eva (referee) ; Kovalčík, Adriána (advisor)
This diploma thesis deals with 1) the preparation of biodegradable polymer films based on polyhydroxyalkanoates (PHA) and 2) their modification by lignin as an active additive. The motivation for this work was to prepare active packaging material for food packaging. Polymer films were prepared by blending of neat crystalline poly(3hydroxybutyrate) (P3HB) and amorphous polyhydroxyalkanoate (PHA). The lignin was isolated from grape seeds derived from grape pomace. The solubility of lignin in chloroform was improved by acetylation. The properties of the isolated lignin were determined by elemental analysis, ash content, and infrared spectroscopy (FTIR). Lignin was used as an active additive for the modification of polymeric films prepared by solution casting of P3HB or P3HB blended with amorphous polyhydroxyalkanoate. The effect of different concentrations of lignin in the range of 1 to 10 % was tested. The lignin type and concentration had a different influence on the final thermal and mechanical behaviour of polymeric films. Lignin increased the values of the Young modulus and tensile strength of the prepared films. Differential scanning calorimetry data confirmed that lignin positively modified crystallization kinetics of P3HB. Thermogravimetry was used to analyse the thermal stability of PHA films. Lignin markedly increased the thermal stability of PHA films. However, acetylated lignin harms the mechanical properties of films. Moreover, this work showed that lignin isolated from grape seeds and added into PHA films proved its high antioxidant capacity. PHA films with lignin displayed much better gas barrier properties compared with PHA films without lignin. The prepared bioactive PHA films fulfil the requirements for sustainable food packaging with high antioxidant capacity and excellent gas barrier properties.
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Development of special protective materials for hygienically clean areas
Seják, František ; Vyhnánková, Michaela (referee) ; Drochytka, Rostislav (advisor)
The diploma thesis deals with the development of special protective materials for hygienically clean plants. The main aim of the thesis is to develop a special protective material on a polymer base usable for hygienically clean industrial plants in two quality levels (economy and premium). The first of the developed polymer protective materials is physiologically harmless (economy) – suitable for contact with eatables. Second, premium material is antibacterial, especially suitable as a floor coating in hospitals, kitchens, sanitary facilities, schools and kindergarten etc. A partial aim is the replacement currently used primary raw materials as fillers by suitable secondary raw material.
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Mechanical and Chemical Surface Endurance of polymers materials, testing and posibilities fro improvements
Vaníček, Štěpán ; Seidlová, Michaela (referee) ; Petránek, Vít (advisor)
Mechanical and chemical resistant multilayer polymeric floors are the most important characteristics of classification in the evaluation of surface and texture. Mentioned as organic binders which are used for the realization of the matrix. Further discussion on how to get fillers forming the supporting folder. Created a summary of the key test of mechanical and chemical characteristics according to current standards. The theoretical part is concluded with a reflection on the possibilities of improving the surface resistance of synthetic floors. The practical part was focused on testing the strength, resistance to impact and adhesion to the base layer. Finally, the overall evaluation of the test results in accordance with the theoretical part.
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Study of the influence of tablet mixture composition on the flow and consolidation properties
Ferechová, Daniela ; Šklubalová, Zdeňka (advisor) ; Macho, Oliver (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Supervisor: Pharmaceutical Technology doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Jana Brokešová Student: Daniela Ferechová Title of Thesis: Study of the influence of tablet mixture composition on the flow and consolidation properties Good flow properties of a tabletting mixture play an important role in the manufacturing of tablets. Flow behaviour of the commercial (original) tabletting mixture with poor flowability was evaluated in this thesis. The main aim was to find alternative fillers that may improve its flow. The granulometric characteristics and flowability of eight types of lactose and microcrystalline cellulose and their binary mixtures were studied. In comparison to the original tabletting mixture, the proposed modified one with both original fillers were replaced with new ones showed significantly better flow properties with steady state flow through the hopper orifice having a diameter of 10 mm. The results were confirmed using powder rheometer. The lower shear stress necessary to achieve flow under different normal loads as well as approximately 72 times lower cohesion value were detected for the modified tabletting mixture.
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Measurement of stress relaxation of mixtures of microcrystalline cellulose and calcium hydrogen phosphate intended for the preparation of tablets with theophylline
Hofmanová, Markéta ; Šklubalová, Zdeňka (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Doc. PharmDr. Sklubalova Zdenka, Ph.D. Student: Marketa Hofmanova Title of Thesis: Measurement of stress relaxation of mixtures of microcrystalline cellulose and calcium hydrogen phosphate intended for the preparation of tablets with theophylline The powder mixtures with theophylline were studied from the aspect of viscoelastic properties of used materials and tablets tensile strength. In the theoretical part the thesis concerned with description of materials which were used in the mixtures. They are: Microcrystalline cellulose Comprecel 102, calcium hydrogen phosphate anhydrate Di-Cafos A150, calcium hydrogen phosphate dihydrate Di-Cafos D160 and lactose SpheroLac 100. The thesis also deals with the stress relaxation test. The stress relaxation test, its evaluation by several methods and its use in the pharmacy and in different fields are described. The experimental part deals with viscoelastic characteristics of the mixtures. These characteristics were evaluated by stress relaxation test with maximal compression force 10 kN and dwell time 180 s. Also the tensile strength was evaluated. The highest values of parameters of elasticity A1-3 and plasticity P1-3 were measured in...
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The effect of particle size on lactose compressibility
Havlíková, Natálie ; Ondrejček, Pavel (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Consultant: PharmDr. Pavel Ondrejček, Ph.D. Student: Natálie Havlíková Title of Thesis: The effect of particle size on lactose compressibility It is known that the particle size of the compressed material plays an important role in the manufacture of tablets. It affects the properties of intermediate and final products. In this thesis the properties of tablets made of two lactose types, which were used as model fillers, were studied. These were Tablettose® 80 and Lactopress® Anhydrous. In both lactose types, five sieved size fractions of the particle size ranging from 9 to 346µm and their original unsieved mixture were used. The compaction forces ranging from 2 to 10kN were used for tablet preparation. Magnesium stearate was used for external lubrication. The evaluation of the prepared tablets was done mainly by using the pharmacopoeial methods. The evaluated parameters were friability, disintegration time and hardness. Furthermore, the elasticity of the tablets and the evaluation using the force-displacement method parameters were assessed. From the results of this work, it is not possible to unambiguously determine the advantage of one particular fraction size in the comparison to the...
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Determination of flow properties of mixtures for preparation of tablets containing theophylline
Brunettová, Monika ; Šklubalová, Zdeňka (advisor) ; Mužíková, Jitka (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Consultant: Doc. PharmDr. Šklubalová Zdeňka, Ph.D. Student: Brunettová Monika Title of Thesis: Determination of flow properties of mixtures for preparation of tablets containing theophylline The aim of this diploma thesis was to characterize the flow properties and moisture content of mixtures for preparation of tablets containing theophylline. Parameters were monitored depending mainly on the content of the fillers, that were dicalcium phosphate, microcrystalline cellulose and lactose. Twenty-five prepared mixtures with different ratios of these fillers were evaluated. Flowability was evaluated by three methods stated in Czech Pharmacopoeia 2009 - compressibility index and Hausner ratio, flow through an orifice and angle of repose. Moisture content was evaluated as a weight loss during drying. Mixtures containing dicalcium phosphate and lactose proved more appropriate in terms of flowability, their flow properties are passable. However, according to the moisture content, mixture with microcrystalline cellulose are more preferable.
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Evaluation of tensile strength of tablets containing theophylline
Janoutová, Hana ; Šklubalová, Zdeňka (advisor) ; Ondrejček, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: Doc. PharmDr. Zdeňka Šklubalová, Ph.D. Student: Hana Janoutová Title of Thesis: Evaluation of tensile strength of tablets containing theophylline The aim of this thesis was to determine tensile strength of tablets containing theophylline. Tensile strength was studied as a function of the composition of mixtures of the used fillers and especially on their ratio. In the theoretical part, the used materials - lactose SpheroLac 100, microcrystalline cellulose Comprecel 102, dibasic calcium phosphate dihydrate Di-Cafos D160, anhydrous dibasic calcium phosphate Di-Cafos A150, theophylline and magnesium stearate are described. This work also evaluates force-displacement record, tensile strength and various factors that affect tensile strength. Parameters of force-displacement record and tensile strength of the tablets compressed with compresssion force 10 kN were evaluated in the experimental part. The measured results show that higher values of precompression energy (E1) and energy of plastic deformation (E2) were detected in mixtures A, C and E which contain Comprecel 102, and the lowest values were detected in mixtures B which contain Sphero-Lac 100 and Di-Cafos D160. Values of energy...
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