Investigating entanglement-driven shape memory property: Insights and structure-property relationships from recent developments

Shape memory polymers (SMPs), particularly those influenced by entanglement effects, are gaining significant attention. These polymers exhibit notable shape-changing properties on a macroscopic scale and intricate structural characteristics on a microscopic level. Entanglements play a crucial role in the shape memory process of certain polymer systems, especially in physically crosslinked systems, and thus this mechanism offers potential for expanding the use of thermoplastic polymers in SMPs, which is particularly promising for applications requiring specific material properties, such as biomedical devices. Despite their promise, a comprehensive understanding of entanglement based SMPs remains elusive due to limited research and reviews in this area. This perspective endeavours to bridge this gap by delving into the intricate relationship between the shape memory characteristics of SMPs and their underlying structural properties, with a focus on entanglement-driven mechanisms. We attempt to conduct a comprehensive review of recent advancements on entanglement-driven shape memory polymers and analyse existing data to explore these complex interactions, and thus attempt to understand how these developments are contributing towards enhanced shape memory properties.