Tapioca-starch-based bionanocomposites with fructose and titanium dioxide for food packaging and fertilization...

Bionanocomposites offer a promising solution to the plastic waste crisis. Although tapioca starch shows potential as a bioplastic material, it is characterized by low mechanical properties, poor thermal stability, and high water absorption owing to its hydrophilic nature. To increase the flexibility of the material and reduce the transmission rate of oxygen and water vapor, additives such as fructose and titanium dioxide (TiO₂) can be incorporated into the material. TiO₂ nanoparticles are commonly utilized in agriculture to enhance nutrient release and promote plant growth. In this study, X-ray diffraction analysis revealed that TiO₂ reduced crystal size while increasing the crystallinity of bionanocomposites. Fourier-transform infrared spectroscopy analysis revealed an absorption peak at 3397 cm^-1, indicating hydrogen bonding between TiO₂ and starch-OH groups, and a peak at 773 cm^-1, indicating an increase in the intensity of Ti-O-Ti stretching vibrations with the incorporation of TiO₂. Water absorption rate results confirmed that TiO₂ addition enhanced bionanocomposite resistance to water vapor and moisture, evidenced by increased tensile strength from 0.11 to 0.49 MPa and Young's modulus from 2.48 to 5.26 MPa, as well as decreased elongation at break from 21.46 % to 2.36 % in bionanocomposites with TiO₂. Furthermore, with TiO₂ addition, the biodegradation rate of the bionanocomposites decreased, which is beneficial for enhancing plant nutrient content.