Hydrogel-shape memory polymer synergistic effect enabled 4D-printed ceramic precursors with programmable recovery onset and reversible deformation

Ceramic 4D printing, which integrates dynamic deformation with additive manufacturing, demonstrates significant potential in intelligent manufacturing, on-demand shaping of complex structures, and multifunctional device development. Its core advantage lies in endowing materials with environmentally responsive dynamic deformation capabilities. However, current technologies still face limitations in responsiveness, reversibility, and mechanical performance. To address these challenges, this study proposes a programmable ceramic precursor system based on synergistic reinforcement of phase-separating hydrogels and shape memory polymers, combined with a nano-ceramic particle enhancement strategy. Using stereolithography 3D printing, high-precision fabrication of complex structures was achieved. By adjusting precursor composition, programming time, and structural thickness, the phase-separation kinetics-driven delayed recovery mechanism was elucidated, enabling precise control over recovery onset time. Furthermore, the thermal response mechanism of the precursor materials is explored, along with their potential for multi-shape transformation in biomedical applications, which is further extended to shape memory polymer systems. By employing a layered printing strategy, the autonomous reversible deformation of ceramic precursors is realized, providing new possibilities for specific applications.