Design Framework of Melt‐Electrowritten Sinusoidal Microstructured Scaffolds for Mechanical Reinforcement of Soft Biomaterial Composites

ABSTRACT Soft biomaterials have found widespread applications across the biomedical field; however, single‐component soft biomaterials suffer from a limited tunable range of mechanical properties. To address this critical limitation, this study fabricated sinusoidal microlattice scaffolds via melt electrowriting technology and embedded them into soft biomaterials for mechanical reinforcement. A theoretical design framework was constructed for sinusoidal microlattice scaffolds to forecast the relationship between the mechanical behaviors of the materials and three key geometric parameters: amplitude, wavelength, and fiber diameter. Additionally, a lag error trajectory compensation strategy was developed to ensure the high‐precision fabrication of the scaffolds. To validate the theoretical model, experimental tests and finite element simulations were conducted on sinusoidal microlattices with three distinct topological structures (triangular, orthogonal, and rectangular), revealing excellent agreement between the theoretical predictions, experimental results, and simulation outcomes. Mechanical characterizations of lattice‐hydrogel composites confirmed that sinusoidal microlattice scaffolds exert a remarkable reinforcing effect on soft biological matrices. Specifically, the scaffolds significantly enhanced the ultimate stress and failure strain of hydrogels, while maintaining excellent interfacial compatibility between the scaffold and the matrix. Numerical results further demonstrated that modulating the geometric parameters enables broad‐range regulation of the scaffold's mechanical properties, including elastic modulus (ranging from several kPa to several MPa), extensibility (with a maximum strain of 226%), and Poisson's ratio (varying from 0.46 to 1.75). This study provides a novel theoretical approach and technical support for predicting the mechanical properties of microlattice structures and rationally designing mechanically reinforced soft biomaterials, thereby holding great significance for advancing biomedical fields.