Recently, the food packaging industry has focused on developing an eco-friendly and sustainable food packaging system. This study describes the effect of beeswax on the physical, structural, and barrier properties of a polyvinyl alcohol (PVA)/polyacrylic acid (PAA) composite film. The incorporation of beeswax improved the barrier properties against oxygen, water, and oil. However, the addition of a high content of beeswax caused phase separation in the film-forming solution. The destabilization mechanisms such as clarification and creaming formation in the film-forming solution were revealed by turbidimetric analysis. The results of scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) indicates that non-homogeneous structures in the film-forming solution were formed as a function of increased beeswax content due to the agglomeration of beeswax. The mechanical properties of the films were also evaluated to determine the most appropriate content of beeswax. There was a slight decrease in tensile strength and an increase in elongation as beeswax content increased up to 10%. Thus, the PVA/PAA composite film with 10% beeswax was chosen for further applications. In summary, the PVA/PAA composite film developed in this study with 10% beeswax exhibited a significant improvement in barrier properties and has the potential for use in commerce.
Keywords: barrier properties; beeswax; emulsion stability; polyvinyl alcohol; structural properties.