Effect of strengthening agents on properties of dual-modified cassava starch-based degradable films

Insufficient hydrophobicity and mechanical properties pose significant challenges in the development of starch-based degradable films. This study prepared modified (crosslinked, acetylated, and crosslinked & acetylated) cassava starch films, and different concentrations of strengthening agents (polyvinyl alcohol, sodium alginate, gelatin, and hyaluronic acid) were added to produce modified starch composite films. The physical properties, structure characteristics, and degradability of these films were systematically evaluated. The dual-modified (crosslinked & acetylated) starch film exhibited superior hydrophobic properties (contact angle = 90.04°), and the addition of strengthening agents significantly enhanced the tensile strength of the composite films (p < 0.05). Fourier transform infrared spectra confirmed that the strengthening agents interacted with starch through hydrogen bonding. Additionally, the hyaluronic acid-starch composite film exhibited the most rapid degradation in soil (53 % weight loss after 30 days of storage) and achieved the highest comprehensive score for physical properties. This film combined exceptional hydrophobicity and mechanical properties, making it an ideal candidate for food packaging applications. These findings suggest that the hyaluronic acid-starch composite film has broad potential applications in the field of degradable food packaging films.