Development of chitosan/poly (vinyl alcohol) active films reinforced with curcumin functionalized layered clay towards food packaging

Nowadays, biodegradable active packaging materials have drawn wide attention which can overcome the serious environmental and food safety problems caused by traditional synthetic materials. In this study, we have reported developing a two-component, chitosan (CS) and poly (vinyl alcohol) (PVA) based films reinforced with curcumin functionalized layered double hydroxides (LDHs@CUR) via solvent casting method. The results showed that CUR was successfully loaded on the LDHs surface, and the thickness of the functional layer was 5 nm. The infrared and thermal analysis revealed that there was a strong interaction between LDHs@CUR and CS/ PVA matrix, which was responsible for the enhancement of water resistance and mechanical properties. When the amount of LDHs@CUR reached 7 wt%, UV barrier properties (at 280 nm) and antioxidant activity of LDHs@CUR/CS/PVA active films were improved by 80.6 % and 49.2 % compared with CS/PVA matrix, respectively. The tensile strength of LDHs@CUR/CS/PVA active films reached a maximum of 60.7 MPa, an increase of 43.8 % compared with CS/PVA matrix, which was attributed to the internal interface interaction and increased crystallinity. These results indicated that the benefits of incorporation for LDHs@CUR into the active CS/PVA matrix and the potential application used as active films/inner coatings to develop food packaging materials.

Automated summary

In this study, a two-component, chitosan and poly (vinyl alcohol) based films reinforced with curcumin functionalized layered double hydroxides (LDHs@CUR) were developed via solvent casting method. The LDHs@CUR showed successful loading on the LDHs surface with a thickness of 5 nm. The LDHs@CUR/CS/PVA active films exhibited improved UV barrier properties, antioxidant activity, and tensile strength compared to the CS/PVA matrix, demonstrating the potential application of LDHs@CUR as active films/inner coatings in food packaging materials development.