Mechanochemical–Mediated Lignocellulose Reassembly for High‐Strength, Sustainable Bioplastics

ABSTRACT The accumulation of petroleum‐based plastics poses severe environmental challenges, highlighting the urgent need for sustainable bioplastic, but achieving high performance and sustainability simultaneously through facile processing remains challenging. Here we introduce a simple mechanochemically assisted cell wall engineering strategy that upgrades bamboo residues into strong, recyclable, and biodegradable bioplastics with 95.4% biomass utilization. Under mild alkali‐assisted ball milling (AABM), cellulose fibrillation and uncondensed lignin migration occur simultaneously, enabling hot‐pressing into dense, lignin‐reinforced composites. The resulting all‐bamboo‐based bioplastic (ABBP) demonstrated excellent water stability, broad solvent resistance, and outstanding mechanical properties: the film reaches a tensile strength of 123.6 MPa, a tensile modulus of 2.9 GPa, while the compression‐molded dense plate attains a flexural strength of 125.0 MPa, a flexural modulus of 6.8 GPa, and a hardness of ∼ 450 MPa. The process is simple, low cost and relies on renewable inputs. The one‐step, scalable approach valorizes bamboo residues into high‐strength materials, establishing a sustainable paradigm aligned with circular economy principles.