Preparation of bioplastic materials based on thermoplastic chitosan and starch by melting mixing method

Abstract The thermoplastic chitosan/starch material was prepared through the utilization of melt mixing in this research. The chitosan/starch compound is plasticized using a mixture of glycerol and ethylene glycol in a ratio of 2:1. The present study evaluated the impact of chitosan concentration on the structural and material properties through the utilization of various analytical techniques, including X‐ray diffraction, Fourier transformative infrared spectroscopy, scanning optical microscopy, water absorption, and mechanical properties. The utilization of SOM imaging revealed that the dispersion of chitosan within the starch phase was homogeneous when the chitosan content was below 9%. The study findings indicated that the incorporation of chitosan into thermoplastic chitosan/starch material resulted in a decrease in moisture absorption under varying humidity conditions (52%, 75%, and 85% RH). The results indicated that the material's hidden absorption is comparable in both environments, with a saturated moisture absorption range of 19%–25%. However, the material exhibited a significantly higher level of humidification at RH 85%, with an interaction range of 40%–48%. Furthermore, the findings suggested that an increase in chitosan content was positively correlated with an increase in tensile strength while negatively correlated with elongation at break.