Formulation and Properties of Agar-Based Biopolymer Blends for Packaging Applications

Abstract In response to environmental concerns surrounding conventional plastic packaging, this study investigates the development of biodegradable bioplastic blends using agar as a primary component. Through iterative experimentation and exploratory development, three categories of formulations were investigated: agar-glycerol films, agar-glycerol-starch films, and agar-glycerol-starch-chitosan films. The experimental process involved iterative optimization of preparation techniques. For basic formulations, agar and glycerol were combined with water and heated under continuous stirring until complete dissolution. More complex formulations required specific sequences of component addition, with chitosan being pre-dissolved in vinegar before incorporation. Films were characterized through visual assessment, physical property measurements, and handling behavior evaluation. Results demonstrated that films with optimal agar-to-glycerol ratio (3–4g:1.6mL per 160mL water) provided the best balance of flexibility and structural integrity. Weight-to-area analysis showed consistent material distribution in basic formulations (0.00366–0.00860 g/cm2), while complex formulations exhibited higher values (0.02008–0.02814 g/cm2). Process improvements, including pre-treating molds with coconut oil and optimizing pouring temperature, significantly enhanced film quality and stability.