Advancing cellulose-based films: A systematic review of mechanical property enhancement strategies

The non-degradability of petroleum-based plastic films has caused irreversible global ecological damage, driving urgent demand for eco-friendly alternatives. As a sustainable, renewable, and biodegradable biomass material, cellulose emerges as an ideal substitute for plastic films, yet its industrial application is hindered by mechanical performance limitations. This review systematically summarizes strategies to enhance the mechanical properties of cellulose-based films, aiming to provide valuable references for researchers and engineers. First, a brief introduction about main cellulose types and common fabrication methods are introduced. Furthermore, core enhancement strategies are then elaborated from four aspects: scale optimization, structural design, densification treatments, and interfacial interaction regulation. In addition, advanced characterization techniques for film structure and fracture mechanisms are also summarized, including SEM/TEM for microstructure observation, universal testing machines for mechanical property measurement, and in-situ methods for real-time crack propagation analysis. Finally, key challenges and future development directions are discussed.