Bioinspired Gradient Minimal Surface Structural Materials via Vat Photopolymerization Towards Efficient Impact Resistance

ABSTRACT To address the growing complexity of protective requirements across diverse scenarios, structural materials should simultaneously achieve light weight, high strength, and efficient energy dissipation. In this work, we propose a synergistic strategy combining material toughening design with biomimetic structure construction. First, a novel hybrid polyurethane acrylate (HPUA) photosensitive resin with high strength (26.1 MPa) and toughness (3.6 MJ/m 3 ) is developed, exhibiting superior comprehensive mechanical performance (e.g., puncture energy up to 249 J/m) compared to commercial photocurable resins. Subsequently, based on the high‐precision manufacturability of this resin system, a bioinspired gradient TPMS (BGT) structure is fabricated by utilizing digital light processing (DLP) technology. Drop‐weight impact tests reveal that the BGT structure exhibits exceptional impact resistance, demonstrating significantly higher peak impact force and energy absorption capacity compared to the normal TPMS (NT) structure and various lattice configurations. Numerical simulations and CT‐based reconstructions further provide theoretical verification of the underlying energy dissipation and damage regulation mechanisms in the BGT structure. Furthermore, by infiltrating flexible polymer phases into the BGT structure, the peak force and energy absorption efficiency can be precisely regulated, enabling tailored performance to meet diverse engineering requirements. This work provides valuable insights for the development of gradient structures and multiphase designs.