Antioxidant and UV Shielding Dual‐Functional Bio‐Based Superhydrophobic Film for Sustainable Food Packaging: Lignin– TPS Based Composite Coating System

ABSTRACT As a hydrophobic coating agent formulated with methyltrimethoxysilane (MTMS) and nano‐silica (SiO 2 ) was coated on the lignin‐reinforced thermoplastic starch (TPS), a sustainable packaging material with excellent antioxidant, ultraviolet‐resistant, and high‐barrier properties was developed. The TPS/lignin composite substrate was prepared by extrusion, and MTMS/SiO 2 was coated on the surface of TPS/lignin through a spraying process. The composite samples were subjected to a series of characterizations and tests, including SEM, FT‐IR, water contact angle measurement, antioxidant property analysis, and UV shielding performance evaluation, and so forth. The results revealed that the introduction of lignin effectively improved the mechanical properties and ultraviolet shielding characteristics of the composite film, and the coating of MTMS/SiO 2 endowed the composite super hydrophobicity, for example, the water contact angle reaches over 157.26°. The water vapor transmission rate of the composite is reduced to 626.17 g/(m 2 24h), the ultraviolet shielding rate exceeds 99%, and the DPPH radical scavenging rate is reached 83.15%. In addition, the composite exhibits outstanding biodegradability. Overall, this study provides new ideas for the development of high‐performance, multifunctional, and environmentally friendly food packaging materials.