Recent Advances in the Field of Shape-Memory Polymer from Bio-Based Precursors: Review and Perspective

Shape-memory polymers (SMPs) are predominantly derived from nonrenewable resources due to their low production cost, wide availability, and refined techniques for processing and tailoring SMP properties. However, the heavy reliance on these nonrenewable resources poses significant concerns regarding resource depletion and the long-term sustainability of the technology. As petroleum-based resources, which have traditionally fueled the polymer industry, become increasingly scarce, it is imperative to develop bio-based SMPs. This shift is essential not just for resource conservation but to ensure the continued viability and sustainability of SMP technology in the face of dwindling petroleum supplies. This review provides an overview of bio-based SMPs, which are synthesized from renewable precursors or through chemical variation and functionalization of biopolymers. The molecular mechanism and design strategy for the shape-memory effect (SME), syntheses, unique characteristics and shape-memory performance for these bio-based SMPs are covered. Furthermore, this review highlights novel insights and proposes promising directions for the development of sustainable SMPs with comparable performance to their nonrenewable counterparts. By focusing on bio-based alternatives, this work aims to motivate the exploration and advancement of next-generation sustainable SMPs.