The broader application of cellulose-based packaging has been restricted by its inherent limitations in mechanical and barrier properties, despite the advantages of biodegradability and renewability. In a new study, a cellulose-based composite packaging material was developed through the incorporation of an ultra-thin layer of silane-modified regenerated cellulose coating, which was reinforced with cellulose nanocrystals (CNCs), onto a cellulose-based substrate. The composites, incorporating an ultra-thin coating, weighing just 0.4 g/m2, demonstrated notable enhancements in hydrophobicity, gas barrier properties, and mechanical characteristics compared to the untreated cellulose-based materials. Potential applications in functional packagingThe water contact angle of the composites reached up to 110.4°, indicating a significant shift towards hydrophobic surfaces. As the researchers point out, the composites developed in this study demonstrate excellent barrier and mechanical properties, thereby expanding their potential applications in functional packaging.