| Abstract [eng] |
Due to the extremely widespread and abundant use of plastics in various fields, there is an increase in the amount of waste in landfills, a large amount is released into the environment and the oceans. In the research for alternatives, biodegradable polymers are the solution to reducing pollution. For this reason, starch is considered be one of the most promising substances due to its positive properties: biodegradability, low cost and abundant availability. The fields of application of starch remains limited due to its retrogradation, high viscosity. Chemical modification of starch is one of the most active research methods to reduce the amount of hydrogen bonds in starch. Modification of starch reduces its inherent retrogradation, but also improves its properties: adhesion, film formation. Starch esters with different degrees of substitution were synthesized using different anhydrides of organic acids (acetic acid, octenylsuccinic, succinic acid and phthalic acid anhydrides). The thermal dependences of the obtained starch esters synthesized with different organic acid anhydrides on the degree of substitution were studied, also the changes in hydrophilicity and granulometric structure were evaluated. Optimization of the starch esterification process was also performed by changing the selected parameters: reaction temperature, reaction time and amount of catalyst. Starch acetate octenyl succinate has been found to have optimal properties with a degree of substitution of 0.06 by octenyl succinic groups and at least 1.23 by acetate groups, a glass transition temperature of 171 ºC and sufficiently high contact angle values. A technological line for the production of such a product was also proposed. |
