GEOLINKS International Conference 2019, Book 2
THERMOPLASTIC COMPOSITION WITH MODIFIED POROUS CORN STARCH OF BIODEGRADABILITY PROPERTIES
Prof. Dr. Valentina Kolpakova, PhD Student Ivan Usachev, PhD Aleksandr Papakhin, Sc. Aslan Sardzhveladze, PhD Vladimir Ananiev
The purpose of research works was to develop a thermoplastic composition with porous (modified) corn starch used to give biodegradable properties to a synthetic polymer (polyethylene of low density) with more effectively, than native corn starch. The expected effect is a wider range of modifying components for biodegradable polymeric products based on polyethylene, reduced emissions polluting the environment due to more intensive decomposition in surrounding conditions (light, atmospheric precipitation, microorganisms etc). For this purpose, there are defined ratios of the principal component (porous starch) and softeners (sorbitol, glycerin) to improve physicomechanical properties of thermoplastic starch and the polymeric composition prepared on its basis. There are specified parameters of thermoplastic starch and polyethylene film based on the hybrid composition with porous starch received by extrusion.
Beforehand the way of enzymatic modification of native starch by its hydrolysis is developed for receiving a hybrid composition with porous corn starch at the temperature below the initial point of gelation in the presence of amylolytic enzymes. Starch had a particular degree of hydrolysis, made in the heterogeneous medium and under optimal conditions. Physicomechanical characteristics of a film at a various ratio of components are investigated with taken into account standard values of the maximum tension and the specific break extension. The composition had rheological characteristics corresponding to requirements claimed to materials being processed on the traditional equipment for plastic. Film products had the production characteristics indicating the ability to decay in vivo with greater speed, than products with native corn starch.
сorn starch, thermoplastic composition, extrusion method, polymeric film, biodegradability