Development of 4D printed shape memory polymers in biomedical field

Shape memory polymers (SMPs) as a class of smart materials, can remember various shapes and return to their original shapes upon external stimuli. 4D printing that is the combination of 3D printing and SMPs has been used for fabrication of various SMPs in many areas of science and technology. At present, 4D printing technology plays an important role and shows promising applications in biomedical field. 4D printing breaks through the technical bottleneck of customization in traditional medical field and provides a new opportunity for the further development of biomedical field. In this article, we review the research progress of SMPs, 3D printing technology and 4D printed SMPs used in biomedical science. Moreover, we introduce some typical biomedical applications of 4D printing of SMPs. Furthermore, we summary the application prospects, existing problems and future development direction of 4D printed SMPs in biomedical field.