STRUCTURAL CHANGES OF BIOPOLYMER MATERIALS DURING HEAT PROCESSING AND PRESS

Zaradi pomanjkanja fosilnih virov in negativnega vpliva plastike in polimerov na osnovi nafte na okolje so raziskave usmerjene k njihovi zamenjavi z naravnimi in obnovljivimi viri. V diplomskem delu so prikazane mehanske in druge lastnosti termoplastičnega škroba z dodatki različnih nanodelcev. Namen diplomskega dela je bil razviti biopolimerni film na osnovi škroba za industrijsko rabo in s čim manjšo prepustnostjo vodne pare ter čim boljšimi mehanskimi lastnostmi. Material smo gnetli v Brabenderjevem gnetilniku pri različnih temperaturah in obratih ter ga stisnili na laboratorijski stiskalnici. Določevali smo natezno trdnost, prepustnost vlage skozi vzorec, viskoznost, termično analizo, posnetke površin vzorcev in kemijske spremembe z infrardečo spektroskopijo. Ugotovili smo, da filmi termoplastičnega škroba, ki smo jih uporabili v diplomskem delu, ne zadoščajo pogojem za neposredno industrijsko rabo.Research is focused on replacing petroleum-based plastics and polymers due to the shortage of fossil resources and their impact on the environment with renewable resources. Mechanical and other properties of thermoplastic starch are shown in diploma work with different nanoparticles. The purpose of this diploma work is to develop a biopolymer film based on starch for industrial usage with minimal permeability of water-vapour and with good mechanical properties. Material was processed in Brabender machine with different temperature and rotor speed and pressed on laboratory press. We studied elongation break, effect of humidity on permeability of film sample, viscosity, thermodynamic analysis, pictures of films surface and chemical changes studied with infrared spectroscopy. Regarding the results we can conclude that films of thermoplastic starch that were used in this diploma work can\u27t be used anywhere in industry