As prominent stimuli responsive material, shape memory polymer composites (SMPCs) have advantages of fast response, long lifetime, high resilience, light weights, stretchable, low cost and easy processing, and have been increasingly used to fabricate morphing structures capable of shape or size alteration in response to external stimulus. In recent years, 3D printing process has been extended into 4D printing with addition of fourth dimension – time. 4D printing can produce smart structures that automatically deform according to the pre-designed settings, allowing the development of “living” adaptable structures from SMPCs. After years of efforts, we have successfully developed a series of shape morphing SMPCs structures through 4D printing, including vascular stent, vascular stent and space deployable structures. Selective incorporation of functional fillers in the defined regions of SMPCs structures enables remote actuation with heat, light, electricity and magnetic field. Multistage, reversible and programmable actuation of the printed SMPCs structures are systematically investigated and discussed. In the final, the challenge and potential are addressed. It is expected that the 4D printing of active deformable SMPCs structures could lead to revolutionary developments in many important areas.
Prof. Jinsong Leng is Cheung Kong Chair Professor and Director of the Center for Smart Materials and Structures at Harbin Institute of Technology (China). His researches cover Sensors and Actuators, Stimulus Responsive Polymers (Shape Memory and Electro-Active Polymers) and their composites, Multifunctional Nanocomposites, etc.Prof. Leng has been served as the Vice President of International Committee on Composite Materials (ICCM), Vice President of Chinese Society for Composite Materials (CSCM). He has also been elected as Member of Academia Europaea, Member of the European Academy of Sciences and Arts, World Fellow of ICCM, Fellow of AAAS (American Association for the Advancement of Science), Fellow of the SPIE, Fellow of Institute of Physics (IOP), Fellow of Royal Aeronautical Society (RAeS), Fellow of Institute of Materials, Minerals, and Mining (IMMM) and Associate Fellow of AIAA.