The work is focused on the study of surface plasma treatment (DCSBD) of films from biodegradable polymers from renewable sources based on polylactic acid (PLA) and polyhydroxybutyrate (PHB). A 4-factor design of experiment was used where the selected variable parameters were the plasma device power, the time of plasma treatment, the ratio of PHB in the polymer blend with PLA, and the content of acetyl tributyl citrate (ATBC) plasticizer in the PLA + PHB blend. The surface total energy and the polar component were evaluated immediately after surface plasma treatment and after 5 h of sitting. Topography of foil surfaces was also studied by AFM. In terms of plasma power and activation time, the greatest increase in surface energy values was observed with a short plasma time of 2 s and a high power of 400 W. Increasing the content of ATBC in interaction with the high concentration of PHB in the blend results in a reduction in the difference of both the polar component and the total free surface energy.
Keywords: biodegradable polymer blends; design of experiment; plasma; polyhydroxybutyrate; polylactic acid.