The aim of this thesis was the preparation of a polymer and two biocomponets based films. Polyvinyl alcohol (PVA) polymer was meant to serve as a matrix basis, cellulosic nanofibriles (NFC) as a strenghtener and pine wood extract as a booster of resilience against microorganisms. We began with preparing all of the components. We first performed a Soxhlet extraction. We used cyclohexane and ethanol as solvents. We analysed the extracts with the gravimetric method, high performance liquid chromatography (HPLC) and UV-VIS spectrophotometry. The extracts had the highest content of pinosylvin monomethyl ether and a somewhat lower content of pinosylvin and nortrachelogenin. Those obtained by cyclohexane contained lesser amounts of extractives than those obtained by etanol. We followed up the extract analysis by rotavaping them, lyophilising the NFC and preparing the PVA water solution. We mixed the composite components using a magnetic mixer and poured the mix into glass petri dishes. The films were dried in the open for two days, followed by 3 weeks at 50 °C in a dryer. As the dried films could not be removed from the surface, we chose the mechanical test of surface scratching. The addition of NFC and with TEMPO reagent modified NFC (TEMPO NFC) preserved or improved the mechanical characteristics of the PVA polymer. The extractives alone had a negative effect on the film hardness, but a positive one when combined with NFC. The results of the study showed that the most suitable composition was the 98 % PVA, 1 % NFC and 1 % extractives based composite.
|
