Effect of Using Cold Plasma Treatment on the Surface and Physicochemical Properties of Starch-chitosan Composite Film

Background and Objectives: Cold plasma is an eco-friendly and non-thermal technique, which has become an important technology to change the physical and chemical features of polymers. Recently, cold plasma has been considered in the decontamination and modification of packaging materials in the food industry. Therefore, the objective of this study was to survey the effect of using low-pressure oxygen plasma treatment on the surface and physicochemical properties of starch-chitosan composite films. Materials & Methods: The low-pressure oxygen plasma treatment of starch-chitosan composite films was carried out using a plasma cleaner system at various times (4, 8 and 12 min). Afterwards, the surface properties and physicochemical properties of untreated and plasma-treated films were compared. Results: The surface roughness and hydrophilicity of the films were increased after tlasma treatment. The tensile strength of the plasma-treated films was improved. Plasma treatments decreased the oxygen permeability of the films but no significant change in their water vapor permeability was observed. Conclusion: In this study, although plasma treatment increased the tensile strength and decreased oxygen permeability of the films, their surface hydrophilicity was increased too. There is a need for further studies to modify the starch-chitosan composite film by plasma treatment.