Progress on Mechanism, Characterization and Multiple Shape Memory Effect of Shape Memory Polymer

Shape memory polymer, a kind of smart material that can response to the external stimulation and produce morphology changes, has achieved a plenty of progress in recent years. More initiation methods and advanced memory effects by applying specific chemical structures and reactions to the shape memory system were found by the researchers with further understanding of the shape memory mechanism. Multiple shape memory polymer, as the morphology extension of traditional shape memory polymer, has attracted more interests for its exclusive performance in a memory circle. Polymer blending is an easier way to prepare multiple shape memory system. Recently, a new theoretic breakthrough has been made on multiple shape memory polymer that assures it complex morphological change, making it more potentially applicable in real life. In this paper, we aim to provide more information on the theory and characterization of the polymer's shape memory effect and the development of multiple shape memory polymer in recent years.