Ecological Systems and Devices Annotation << Back Production of Biodegradable Polymeric Material,based on Xanthan Gum and Potato Starch, Modifiedby the Joint Addition of Plasticizers Kornilov K.N. Production of a biodegradable, environmentally friendly polymer film material, composed of potato starch (PS), xanthan gum (XG), and plasticizers: glycerol, sorbitol, and citric acid, was carried out. The effect of these components on the structural and biopolymer composite mechanical properties, including elasticity and tensile strength, was investigated. It has been established that the addition of gum and glycerin to starch significantly reduces the hardness and brittleness of film-forming materials, thereby facilitating the gelatinization process. It was demonstrated that increasing the plasticizers mass during composite blend preparation improved elasticity but reduced the mechanical strength of the films. The effectiveness of glycerol on the elasticity of bioplastics, and sorbitol on its strength, has been confirmed. Taking various factors into account, the optimal combined concentration of glycerol, sorbitol and citric acid was determined in composite during film preparation: 2 % of the initial hydrogel mass for each plasticizer. Based on the results of the new polymeric fi lms’ flexibility study, it was concluded that they could be used as a replacement for traditional, non-biodegradable polymeric materials. At the optimal concentration of components, the strength of polymer films is 1.6 MPa, and the relative elongation is 45 %. Keywords: starch, xanthan gum (XG), biodegradable polymer, polymer film, plasticizer, glycerol, sorbitol, citric acid. DOI: 10.25791/esip.8.2026.1612 Pp. 35-49.