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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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Grafting of polypropylene with derivatives of itaconic acid
Poštulková, Hana ; Běťák, Lukáš (referee) ; Kučera, František (advisor)
Bachelor thesis deals with grafting of polypropylene (PP) by using derivatives of itaconic acid (IA) in the melt phase, specifically with monomethyl itaconate (MMI) and dimethyl itaconate (DMI). Theoretical part focuses on summary of radical initiated grafting of PP with different monomers especially DMI and MMI and factors influencing radical grafting. In experimental part were prepared samples with concentration of monomer 1-5 wt. % and concentration of initiator 1,5-0,15 wt. %. Influence of concentration of monomer, ratio of monomer concentration to initiator concentration and temperature on concentration of grafted monomer and conversion were determined. A Brabender mixer was used for all experiments. Conditions of grafting were 75 rpm, time of reaction 6 minutes and temperature 180-200 °C, initiator Luperox 101. Degradation of polymer chain was determined by MFI. Infrared spectroscopy (FTIR) was used to calculate monomer conversion and concentration of grafted monomer.
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Mechanisms and kinetics of poly(3-hydroxybutyrate) reactions
Melčová, Veronika ; Sedláček,, Tomáš (referee) ; Bakoš, Dušan (referee) ; Přikryl, Radek (advisor)
Tato práce se zabývá reakcemi bakteriálního biopolymeru poly(3-hydroxybutyrátu) s vybranými reaktivními činidly v tavenině. Využity byly sloučeniny různých funkčních skupin; isokyanáty, karbodiimidy, alkoholy a epoxidy; a funkcionality; od dvou po polyfunkční. Cílem je charakterizovat kinetiku termické degradace tohoto polymeru během zpracování samotného a s přídavkem výše uvedených činidel v různých množstvích. Za tímto účelem bylo provedeno reologické měření sestávající ze čtyř po sobě jdoucích frekvenčních testů v rozsahu 0,1–50 Hz a ze získaných dat byl vyhodnocen parametr kvantifikující rychlost poklesu viskozity. Tento kinetický parametr umožnil porovnání účinků jednotlivých činidel. Dále byly připraveny reaktivní vzorky hnětením, při němž byl zaznamenán a diskutován kroutící moment, a také v roztocích, u kterých byla měřena viskozita. U takto připravených vzorků byly studovány tepelné vlastnosti, molekulová hmotnost a infračervená spektra. Z testovaných aditiv vykázaly nejlepší celkové výsledky v provedených experimentech polymerní karbodiimid Raschig 9000, hexamethylen diisokyanát, poly(glycidyl methakrylát) syntetizovaný pro účely této práce a poly(hexamethylen diisokyanát). Pozoruhodné je, že vzorek se 100násobným molárním přebytkem Raschigu měl o 20–30 % nižší rychlost poklesu viskozity v oblasti frekvence 0,1–5 Hz. Kromě toho byl proveden test enzymatické biologické rozložitelnosti s lipázou a v abiotických podmínkách. Nejvyšší rychlost poklesu molekulové hmotnosti vykazoval poly(3-hydroxybutyrát) aditivovaný poly(glycidylmethakrylátem).
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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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Grafting of polypropylene with derivatives of itaconic acid
Poštulková, Hana ; Běťák, Lukáš (referee) ; Kučera, František (advisor)
Bachelor thesis deals with grafting of polypropylene (PP) by using derivatives of itaconic acid (IA) in the melt phase, specifically with monomethyl itaconate (MMI) and dimethyl itaconate (DMI). Theoretical part focuses on summary of radical initiated grafting of PP with different monomers especially DMI and MMI and factors influencing radical grafting. In experimental part were prepared samples with concentration of monomer 1-5 wt. % and concentration of initiator 1,5-0,15 wt. %. Influence of concentration of monomer, ratio of monomer concentration to initiator concentration and temperature on concentration of grafted monomer and conversion were determined. A Brabender mixer was used for all experiments. Conditions of grafting were 75 rpm, time of reaction 6 minutes and temperature 180-200 °C, initiator Luperox 101. Degradation of polymer chain was determined by MFI. Infrared spectroscopy (FTIR) was used to calculate monomer conversion and concentration of grafted monomer.
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