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Solubility of polypropylene in hydrocarbon solvents
Urbánková, Radka ; Kučera, Jaroslav (referee) ; Kratochvíla, Jan (advisor)
Polypropylene, on a mass-scale produced polyolefin, shows an excellent combination of end-use properties, eco-friendliness, easy recyclability, and a good processability by different technologies. Key structural parameters of polypropylene are its stereoregularity, molecular weight, and its distribution. A theoretical part of this work compiles a bibliographic search and an experimental part deals with extraction and solubility of polypropylene powder prepared on a highly active Ziegler-Natta polymerization catalyst. Extractions at a boiling point temperature of solvents (pentane - hexane - cyclohexane - hex-1-ene - benzene - heptane - octane - ethylbenzene) resulted in a progressive increase of extracted portions with temperature of extraction. Solvents used within this work were characterised by their physical properties, and steric and electronic parameters such as molecular weight, density, boiling point temperature, dipole moment, refractive index, and Hildebrand´s solubility parameter. Extraction PP at a constant temperature 36°C (boiling point of pentane) at a saturated vapour pressure in a series of hydrocarbon solvents (pentane – hexane – heptane – octane) resulted in practically the same results. Boiling octane extractable fraction at a temperature 36°C was nearly 100 % higher than fractions extracted by the other solvents. The origin of this phenomenon has not been revealed. Polypropylene solubility was determined by a complete dissolving the sample at 140°C in a series of aliphatic and aromatic solvents (pentane - hexane - cyclohexane - hex-1-ene - benzene - heptane - octane - toluene - ethylbenzene - o-xylene - m-xylene - p-xylene - decalin - chlorbenzene - 1,2-dichlorbenzene), followed by cooling the solution down to a laboratory temperature, and separating a soluble fraction, and an insoluble one. The stereoregularity of soluble fractions was characterised by a 13C NMR method, the crystallinity by a DSC method, and a molecular weight distribution by a GPC method. As a result, polypropylene solubility decreases with increasing the Hildebrand solubility parameter of the solvent that corresponds with theoretical expectations. Moreover, PP solubility correlates strongly with a refractive index, and a density of solvent.
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Testing of processing stability of PP-g-IA
Hampapa, Břetislav ; Tocháček, Jiří (referee) ; Kučera, František (advisor)
The Bachelor’s study is interested in processing stability of polypropylene grafting with Itaconic anhydride. A present knowledge about thermal degradation of Itaconic derivatives was summarized in theoretical part. Samples were prepared by multiple extrusions technique from virgin PP (Borsodchem, Hungary) and PP-g-IA. Die temperature 230 °C, processing time 4 minutes by 20 RPM. Qualitative and quantity analysis was made by FT-IR spectroscopy.
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Grafting of PP using itaconic anhydride and drying agent
Petruš, Josef ; Hermanová, Soňa (referee) ; Kučera, František (advisor)
The bachelor´s thesis deal with a preparation of polypropylene (PP) grafted with itaconic acid (IA) and itaconic anhydride (IAH) arising by thermic dehydration in situ from IA in presence of drying agents. Theoretical part contains actual knowledges especially about radical grafting of polypropylene with different monomers. In experimental part samples of polypropylene grafted with 0.5 wt % IA were prepared with free different drying agents: calcium oxide, aluminium oxide and calcium sulfate hemihydrate. To comparison PP grafted with 0.5 wt % IAH was prepared. Thermic behaviour of IA with drying agent and IAH samples was determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurement. Process of grafting was realized with mixer Brabender at temperature 230 °C, speed was 30 RPM and reaction time 6 minutes. 2,5-dimethyl-2,5bis(tert-buthylperoxy)hexane (Luperox 101) was used as iniciator. Percentage of grafted carboxylic groups was provided by acid-base titration. FTIR spectroscopy was used for quantitative and qualitative analysis of characteristic groups.
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Preparation of grafted PP with diferent concentration of MA and IA
Běťák, Lukáš ; Žídek, Jan (referee) ; Kučera, František (advisor)
The bachelor thesis deal with a preparation and a characterization of polypropylene grafted with anhydrides carboxylic acids in a melt. A present knowledge about radical grafting was summarized in a theoretical part. Samples of polypropylene grafted with itaconic anhydride (IA) and maleic anhydride (MA) were prepared in the experimental part. 2,5 dimethyl 2,5bis(tert-buthylperoxy)hexane (Luperox 101) was used as a radical initiator. A Brabender mixer was used for experiment, conditions for grafting were 210 °C, 30 RPM and 6 min. Weight concentration of grafted monomer was in range 0,25 wt % 1 wt %. It was found that a degree of conversion depended on concentration ratio of initiator to monomer. Attached carboxylic groups to polypropylene backbone were confirmed by FTIR spectroscopy. The percentage of grafting was determined by acid-base titration.
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Preparation of PP composites by grafting using monomer treated filler
Kramerová, Nina ; Žídek, Jan (referee) ; Kučera, František (advisor)
Bachelor thesis is focused on preparation of composite materials with polypropylene matrix. The composites were prepared “in situ” with using Brabender mixer. Homogenization of matrix and filler and grafting of PP with anhydride of itaconic acid treated filler proceed together according to radical mechanism of polymerization. Luperox 101 [2,5-dimethyl-2,5-di(tertbutyl-peroxy)hexane] was used as an initiator of the reaction, the concentration of the initiator was 0.5 wt %, processing temperature 210 °C, 30 rpm. PP-g-IA is a compatibilizer between the matrix and the filler. Glass fibers, calcite and two types of ground wood pulp were used as filler. Two analytical methods were chosen to analyze the efficiency of grafting, acid-base titration and infrared spectroscopy. Assigned conversion of monomer was from 42 to 87 % for various fillers.
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Way of assign of stereoregularity of polypropylene
Hoza, Adam ; Tocháček, Jiří (referee) ; Kratochvíla, Jan (advisor)
The purpose of this work is to evaluate and compare isotactic index value determination of polypropylene homopolymer using extraction and solubility methods. A series of nine PP samples in a powder form specified by molecular weights in the range from 29 to 154 kg/mol was investigated. The methods afforded separation of polypropylene into two portions, the soluble fraction, and the insoluble one. Extractions were carried out in a modified Kumagawa extractor. Polypropylene extracts were obtained using several organic solvents (pentane, hexane, heptane, and octane) at their boiling points. Soluble fractions were obtained by dissolving the PP sample in high boiling point solvents (xylene, decahydronaphthalene, and 1,2,3,4-tetrahydronaphthalene) and cooling the polymer solution to 23°C. All the fractions were characterized using 13C-NMR, SEC, and DSC methods. Comparison of the extraction and solubility methods showed significant differences in the amount, stereochemical structure, molecular weight, and crystallinity of soluble, and insoluble fractions.
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Design and production of a plastic komponent
ČÍŽEK, Václav
The theoretical part is focused on evaluation of chosen ?essential? plastics used in the car industry. The principles of construction and proportioning of plastic components, basic conception of injection moulding and measuration follow. Another section of the theoretical part presents a summary of possible CAD systems, which are used. The practical part is focused on a particular plastic moulding. It includes the main description of a component with its material choice in dependence on the component function. Another section contains evaluation of the component complexity from the viewpoint of moulding, and a possible substitution of constructions, which could be productively simpler, is shown. The whole thesis is completed for better lucidity by pictures, drawings, and mechanical drawings.
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Ekologická likvidace a recyklace plastických hmot
Nippon EKO a.s.
Zpracování polyolefinových odpadů metodou katalytického rozkladu polymerů, při kterém se získávají tekuté uhlovodíky. Produkt získaný tímto způsobem neobsahuje síru, chlor a jiné heteroatomy, což rozhoduje o jeho využitelnosti jako vysoce kvalitního syntetického oleje. Pro výrobu lze použít polymerový odpad, který je stovky let nezničitelný např. zemědělské fólie a obaly vyrobené z polypropylenu, polyetylénu a polystyrenu.
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