Food spoilage, caused by fungi and bacteria, has drawn increasing attention due to the lack of suitable temperature and humidity control, resulting in food waste and health risks. It is still a great challenge to develop green packaging materials with excellent antibacterial activities and effective temperature/humidity control for food preservation. Herein, a new strategy is proposed to obtain food packaging material with antibacterial ability, heat dissipation, and liquid transportation functions. In this strategy, Zn-Al layered double hydroxide (LDH)@cellulose was obtained by extracting cellulose from sugarcane husks, followed by in-situ growth of LDH nanosheets on the surface of cellulose. Then, asymmetric structured packaging material, namely cellulose acetate/LDH@cellulose (CALC) membrane, was prepared by the combination of electrospinning and hydrophobic modification. The characterization results confirmed that the CALC membrane exhibits asymmetric surface structure and wettability properties, endowing heat dissipation and liquid transportation for food packaging applications. Due to the asymmetric reflectivity and infrared emissivity, the CALC membrane exhibited excellent heat dissipation properties with a surface temperature of 10.3℃, which is lower than that of commercial food packaging material. Furthermore, the excellent liquid transport properties of the CALC membrane are demonstrated by the fact that water can penetrate from the hydrophobic side to the hydrophilic side within 32s, providing the appropriate storage temperature and dry environment for foods. In addition, compared with PE film, the CALC membrane also has antibacterial properties and UV resistance, which is beneficial to improving the storage conditions for foods. This study shows that the developed CALC membrane and corresponding design strategy can be extended for the preparation of other packaging materials for applications in research and food industrial fields.
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