Hydrolytická stabilita poly(3-hydroxybutyrátu)

Abstract

Bakalárska práca sa zaoberá skúmaním hydrolytickej stability poly(3-hydroxybutyrátu) pri hydrolýze v nadbytku vody a pri hydrolytickej degradácii v tavenine. V teoretickej časti práce sú zhrnuté poznatky o priebehu, mechanizme a kinetike hydrolýzy a prehľad ďalších rozkladných reakcii poly(3 hydroxybutyrátu). Experimentálna časť je zameraná na degradáciu poly(3-hydroxybutyrátu) v prítomnosti vody a porovnanie miery hydrolytickej degradácie pri kyslo a alkalicky katalyzovanej reakcii. Na porovnanie rozsahu hydrolýzy v tavenine bola skúmaná hydrolytická degradácia poly(3 hydroxybutyrátu) v extrudéri pri teplote 170 °C. Vzorky boli analyzované na zistenie objemového indexu toku, teploty topenia, stupňa kryštalinity, distribúcie molekulovej hmotnosti a štruktúry poly(3-hydroxybutyrátu) pomocou infračervenej spektroskopie.The bachelor thesis deals with the study of hydrolytical stability of poly(3-hydroxybutyrate) in the hydrolysis with excess of water and in the hydrolytic degradation in melt. Theoretical part summarises knowledge about the process, mechanism and kinetics of hydrolysis and contains an overview of further decomposition reactions of poly(3-hydroxybutyrate). Experimental part is focused on degradation of poly(3-hydroxybutyrate) in the presence of water and on comparing the rate of hydrolytical degradation with acidic and alkaline catalysis. In order to comparing the range of hydrolysis, hydrolytic degradation of poly(3-hydroxybutyrate) was investigated in extruder at the temperature of 170 °C. Samples were analyzed to determine the melt volume index, melt temperature, degree of crystallinity, distribution of molecular mass and the structure of poly(3 hydroxybutyrate) using infrared spectroscopy.