Multifunctional and pH‐responsive dialdehyde cellulose/polyvinyl alcohol composite film reinforced with curcumin

Abstract The rational design of food packaging films with good antimicrobial activity, antioxidant activity, and monitorability is of great importance in intelligent packaging. In this study, an active composite film was prepared by adding curcumin to a dialdehyde cellulose (DAC)/polyvinyl alcohol (PVA) matrix. It was found that the Cur/DAC/PVA composite film exhibited optimal tensile strength at 30°C. The tensile strength of the composite film control PVA/DAC film was observed to increase by 176% due to the affection of hydrogen bonding. Under the influence of curcumin, the UV barrier property and antioxidant activity of the composite film were significantly increased, and the ABTS + • was removed by 0.5Cur/DAC/PVA up to 88% at low curcumin content. The water solubility and water vapor permeability were both reduced to some degree. It was also observed that composite film displayed an inhibitory effect on the growth of Staphylococcus aureus bacteria. Meanwhile, the Ritger and Peppas release model was used to study the release control capability of curcumin. Furthermore, the Cur/DAC/PVA composite film demonstrated excellent color response to pH, which it they could be used for intelligent packaging with real‐time visual monitoring.