Programmable polylactic acid–ceramics 4D printing with shape memory function

4D printing is an emerging advancement in additive manufacturing that enables responsive materials to undergo shape transformations, achieving dynamic behaviours. However, 4D printing of ceramics remains challenging due to their brittleness and limited deformability. In this study, we synthesise a novel multifunctional polymer-derived ceramic precursor (PDCP) with reconfigurability and shape memory properties for 4D printing. Programmable 4D printing via stereolithography was achieved by leveraging the glass transition and melting temperatures of the material. Unlike conventional ceramic precursors, which retain a static shape, the proposed PDCP exhibits autonomous deformation through a two-step curing process: first, photopolymerization establishes an initial form, followed by heating/melting to programme the final shape. Most PDCPs with shape memory effects can only set a single permanent shape, whereas ours allows for reconfiguration and resetting of a new permanent shape. Additionally, simulations are conducted to analyse the shape change behaviour of the PDCP. The incorporation of polylactic acid into the precursor significantly enhances its mechanical properties, with tensile strength increasing by 200% to 300% compared with previously studied flexible PDCPs. Furthermore, the shape memory function of polylactic acid is inherited by the PDCP, presenting promising applications in aerospace and military fields where adaptable ceramic structures are highly valuable.