Investigation of the effect of ultrasonic exposure on polymer solutions in the production of biodegradable packaging materials

One of the options for improving the structure and properties of films obtained from polymer solutions is ultrasonic exposure to solutions of various chemical nature. The use of this effect on polymer solutions with various additives and agents showed not only an improvement in physical and mechanical properties, but also antibacterial properties, which contributed to an increase in the shelf life of food products. The main components of the compositions whose studies are presented in scientific articles were: polyvinyl alcohol, proteins and pullulan, they were mixed with various additives and agents, with different duration of exposure to ultrasonic treatment of solutions. The studied compositions had the following compositions: polyvinyl alcohol and hemicellulose with an antioxidant agent of tea; polyvinyl alcohol, sodium-carboxymethyl cellulose, zinc oxide nanoparticles, as well as multilayer graphene nanoplates; polyvinyl alcohol and chitosan; fish scale collagen, polyvinyl alcohol and potassium sorbate; egg white; quinoa protein and chitosan; pea protein; rice protein hydrolysate and chitosan; whey protein hydrolysate; aqueous soy extract with bee wax and essential oil of cloves; oat protein with pullulan and nizin; pullulan with the addition of nanoemulsion with cinnamon essential oil; pullulan and trehalose with tea polyphenols saturation. Some of the films made from these formulations were tested on food products such as strawberries, apples, pears and cupcakes. Based on the considered scientific data, it can be concluded that in order to improve the properties of films from polymer solutions, it is necessary to have an optimal time of ultrasound exposure to solutions, since longer ultrasonic exposure can worsen the physical and mechanical properties, namely, to reduce the tensile strength and elongation at break, in contrast to moderate exposure.