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The effect of bio-pigments on the properties of PLA materials for 3D printing
Vacula, Jan ; Figalla, Silvestr (referee) ; Menčík, Přemysl (advisor)
This thesis deals with the influence of naturally derived dyes on the properties of polylactic acid (PLA) for 3D printing using the FDM method. In the production of 3D printing filaments, it was crucial to understand the behavior of bio-dyes within the material. Thermogravimetric analysis (TGA) was performed to determine the thermal stability of the bio-dyes. Based on the resulting thermal stabilities, seven bio-dyes were selected from which concentration series were prepared in the form of 3D printing filaments. The influence of adding bio-dyes to the PLA polymer matrix was defined using gel permeation chromatography (GPC). To assess the impact of bio-dyes on the mechanical properties of the materials, tensile testing and three-point bending tests were chosen. It was found that adding bio-dyes does not significantly reduce mechanical properties. Furthermore, UV stability was investigated through accelerated exposure in a chamber with a xenon lamp. The influence of UV radiation on individual bio-dyes was defined through colorimetric evaluation. The results were key for further development and optimization of the use of natural dyes in the manufacturing process of 3D printing filaments.
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Functionalization of Polypropylene by Grafting
Kelíšek, Petr ; Sadílek, Jiří (referee) ; Petrůj, Jaroslav (advisor)
This bachelor thesis deals with the study of functionalization of polypropylene by grafting. The theoretical part summarizes current knowledge about the properties of polypropylene, polylactic acid, radical grafting, factors influencing the properties of such functionalized polymer and modification of immiscible polymers by the aid of compatibilizer. In the experimental part, samples of polypropylene grafted with polylactic acid, and blends of polypropylene with polylactic acid were prepared on an internal mixer under different conditions. Temperature and torque were monitored during the mixing. Created materials were evaluated by comparing their base properties (tensile strength, melt flox index).
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Study of heat transport throw bulk materials with electric conductive aditive
Vacula, Jan ; Menčík, Přemysl (referee) ; Zmeškal, Oldřich (advisor)
Bachelor thesis is focused on the study of heat transport in bulk materials made from PLA (polylactic acid) filaments by 3D printing. For subsequent applications it is important to know the electrical, dielectric and thermal parameters of materials with different dyes, pigments and electrically conductive additives. The aim of this work is mainly to study the thermal properties of the series and the influence of additives on these properties. The main focus is to study the thermal properties of the samples. In the theoretical part, different 3D printing methods are mentioned, the methods of measuring the thermal properties, and finally the properties of the lactic acid polymer are described. The experimental part is devoted to the description of the process of 3D printing samples for measurements and then the method of measuring the thermal properties of the printed samples is described. For samples with electrically conductive admixtures, the thermal conductivity was found to be in the range of (0,217–0,292) W/m/K and the specific heat capacity was found to be (382,2–1 007,2) J/kg/K. The electrically conductive materials (PLA with metallic admixtures) were found to have a very good thermal conductivity and a smaller specific heat capacity, while the materials with admixtures of dyes and pigments showed a smaller thermal conductivity and a larger specific heat capacity.
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Characterization of blowing films from softened polylactide
Kubíček, Václav ; Tocháček, Jiří (referee) ; Bálková, Radka (advisor)
The master's thesis focuses on preparation of blown films from polylactid acid (PLA) which was blended with selected polyesteres – poly(butylene adipate-co-terephtalate) (PBAT), polycaprolactone (PCL) and polybutylene succinate (PBS) – and thermoplastic starch (TPS) in amount of 30% in order to soften PLA films. The influence of the aditives on static and mechanical tensile properties, on structure, morphology and thermal properties of the films was determined and the obtained parameters were compared to properties of films prepared from neat PLA and high density polyethylene (HDPE). The results showed that the additives increased crystalinity of PLA and thus significantly influenced the properties of the films. In contrast to the film from neat PLA, softening in terms of lowering glass transition temperature occured only by adding PBS and TPS, in terms of increasing ductility only by adding PBAT. All PLA films showed nearly constant elastic modulus up to the beginning of glass transition enabling their potential application till 50 °C. Preparation of the film with TPS was problematic and the film showed the worst mechanical properties. Preparation of other films was without any problems. The most promising additive from the tested ones was PBAT which showed comparable mechanical properties as the film from HDPE.
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Study of Thermal Properties of Materials for 3D Printing
Lapčíková, Tereza ; Menčík, Přemysl (referee) ; Zmeškal, Oldřich (advisor)
The aim of this bachelor thesis was to study thermal properties of materials used for 3D printing (so-called filaments), especially a polylactic acid (PLA). Within the theoretical part there was performed the literature review focused on the description of different methods of 3D printing including the summary of suitable materials for these technologies. In particular, we focused on the preparation of PLA, its summarization of its chemical, physical and thermal properties and its practical use in 3D additive printing manufacturing, e.g. in biomedical applications. In the experimental part, PLA samples of different thicknesses were prepared by 3D printing technique and thermal properties such as thermal capacity and thermal conductivity were determined. It was found that thermal conductivity of studied material was 0,128 W/m/K and specific heat capacity 1335 J/kg/K. These values corresponded to the once given in the literature.
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Study of heat transport throw bulk materials with electric conductive aditive
Vacula, Jan ; Menčík, Přemysl (referee) ; Zmeškal, Oldřich (advisor)
Bachelor thesis is focused on the study of heat transport in bulk materials made from PLA (polylactic acid) filaments by 3D printing. For subsequent applications it is important to know the electrical, dielectric and thermal parameters of materials with different dyes, pigments and electrically conductive additives. The aim of this work is mainly to study the thermal properties of the series and the influence of additives on these properties. The main focus is to study the thermal properties of the samples. In the theoretical part, different 3D printing methods are mentioned, the methods of measuring the thermal properties, and finally the properties of the lactic acid polymer are described. The experimental part is devoted to the description of the process of 3D printing samples for measurements and then the method of measuring the thermal properties of the printed samples is described. For samples with electrically conductive admixtures, the thermal conductivity was found to be in the range of (0,217–0,292) W/m/K and the specific heat capacity was found to be (382,2–1 007,2) J/kg/K. The electrically conductive materials (PLA with metallic admixtures) were found to have a very good thermal conductivity and a smaller specific heat capacity, while the materials with admixtures of dyes and pigments showed a smaller thermal conductivity and a larger specific heat capacity.
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Study of Thermal Properties of Materials for 3D Printing
Lapčíková, Tereza ; Menčík, Přemysl (referee) ; Zmeškal, Oldřich (advisor)
The aim of this bachelor thesis was to study thermal properties of materials used for 3D printing (so-called filaments), especially a polylactic acid (PLA). Within the theoretical part there was performed the literature review focused on the description of different methods of 3D printing including the summary of suitable materials for these technologies. In particular, we focused on the preparation of PLA, its summarization of its chemical, physical and thermal properties and its practical use in 3D additive printing manufacturing, e.g. in biomedical applications. In the experimental part, PLA samples of different thicknesses were prepared by 3D printing technique and thermal properties such as thermal capacity and thermal conductivity were determined. It was found that thermal conductivity of studied material was 0,128 W/m/K and specific heat capacity 1335 J/kg/K. These values corresponded to the once given in the literature.
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Characterization of blowing films from softened polylactide
Kubíček, Václav ; Tocháček, Jiří (referee) ; Bálková, Radka (advisor)
The master's thesis focuses on preparation of blown films from polylactid acid (PLA) which was blended with selected polyesteres – poly(butylene adipate-co-terephtalate) (PBAT), polycaprolactone (PCL) and polybutylene succinate (PBS) – and thermoplastic starch (TPS) in amount of 30% in order to soften PLA films. The influence of the aditives on static and mechanical tensile properties, on structure, morphology and thermal properties of the films was determined and the obtained parameters were compared to properties of films prepared from neat PLA and high density polyethylene (HDPE). The results showed that the additives increased crystalinity of PLA and thus significantly influenced the properties of the films. In contrast to the film from neat PLA, softening in terms of lowering glass transition temperature occured only by adding PBS and TPS, in terms of increasing ductility only by adding PBAT. All PLA films showed nearly constant elastic modulus up to the beginning of glass transition enabling their potential application till 50 °C. Preparation of the film with TPS was problematic and the film showed the worst mechanical properties. Preparation of other films was without any problems. The most promising additive from the tested ones was PBAT which showed comparable mechanical properties as the film from HDPE.
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Functionalization of Polypropylene by Grafting
Kelíšek, Petr ; Sadílek, Jiří (referee) ; Petrůj, Jaroslav (advisor)
This bachelor thesis deals with the study of functionalization of polypropylene by grafting. The theoretical part summarizes current knowledge about the properties of polypropylene, polylactic acid, radical grafting, factors influencing the properties of such functionalized polymer and modification of immiscible polymers by the aid of compatibilizer. In the experimental part, samples of polypropylene grafted with polylactic acid, and blends of polypropylene with polylactic acid were prepared on an internal mixer under different conditions. Temperature and torque were monitored during the mixing. Created materials were evaluated by comparing their base properties (tensile strength, melt flox index).
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Bioplastics and their use on market
DĚDEK, Zdeněk
Since the industrial revolution the rise of the global economy depends on using more amounts of fossil fuels. Currently oil is the leading feedstock for the production of various kinds of plastic products, from packaging materials to machine parts. However, even this advanced technology, such as plastic, awarded several Nobel prizes, has its drawbacks. The big disadvantage is their very slow degradation (tens to thousands of years), thereby the accumulation of waste is increasing. Another disadvantage is its production from non-renewable materials (oil). Therefore, the developed economies, including the European Union (EU), are trying to find new alternatives to conventional plastics using biotechnology manufacturers to called bioplastics, which are made from renewable materials. This thesis deals with the use of bioplastics in the market. Using the questionnaires is creating survey of market among producers of bioplastics and consumers, combined with a personal interview with the promoters of bioplastics. Results processed by this methodology showed that the biggest factor, which influence the promotion of bioplastics, is too high price. This is the main reason why the public is so little informed about them. If the price of production decreases, promotion and use of bioplastics will be probably to increase.
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