A biodegradable chitosan-based composite film reinforced by ramie fibre and lignin for food packaging.

To solve the problem of environmental pollution caused by plastic food packaging films, a biodegradable chitosan-based film containing micro ramie fibre and lignin was prepared by the casting method. With the addition of different ratios of ramie fibre and lignin to the chitosan matrix, a significant improvement in mechanical, water resistance, thermal, and antioxidant properties was observed. The addition of 20 wt% ramie fibre increased the tensile strength by 29.6%. Moreover, the addition of 20 wt% of lignin increased the antioxidant activity by 288%, and reduced the water absorption by 41.2%. However, due to their high pyrolysis temperatures, there was little difference between ramie fibre and lignin in improving the thermal stability. Finally, this study compared the food preservation effects of composite films and PE films. The application evaluation results showed that the composite films were more effective. Overall, the chitosan-based films showed great potential for food packaging.