Hybrid 4D printing of flexible multifunctional composites by multi jet fusion and direct ink writing

Four-dimensional (4D) printing, which integrates additive manufacturing with smart materials, facilitates the fabrication of adaptive structures featuring dynamic properties and customizable geometries. However, the incorporation of multiple smart materials for multifunctional devices remains limited. Herein, this work reports a novel hybrid 4D printing technique that uniquely combines multi jet fusion (MJF) and direct ink writing (DIW) to develop multifunctional liquid crystal elastomer–shape memory polymer (LCE-SMP) composites. The unprecedented utilization of MJF in 4D printing allows the rapid fabrication of SMPs with a tunable electric conductivity distribution, while DIW subsequently prints LCEs with programmable mesogen alignment onto the MJF-printed SMPs. The resulting hybrid-4D-printed LCE-SMP composites not only exhibited diverse temporary configurations that remained stable without continuous stimuli but also possessed reversible photo-actuation with high output power, enabling diverse bio-inspired dynamic structure evolution and remote on-demand object manipulation. Simultaneously, the LCE-SMP composites demonstrated robust self-sensing capabilities during actuation tasks, providing real-time feedback on device performance and operational status. This work introduces a novel concept for designing and fabricating multifunctional materials to advance the field of intelligent devices.