Shape Memory Polyurethane Composite With Fast Response to Near‐Infrared Light Based on Tannic Acid–Iron and Dynamic Phenol‐Carbamate Network

Abstract Intelligent materials derived from green and renewable bio‐based materials garner widespread attention recently. Herein, shape memory polyurethane composite (PUTA/Fe) with fast response to near‐infrared (NIR) light is successfully prepared by introducing Fe 3+ into the tannic acid‐based polyurethane (PUTA) matrix through coordination between Fe 3+ and tannic acid. The results show that the excellent NIR light response ability is due to the even distribution of Fe 3+ filler with good photo‐thermal conversion ability. With the increase of Fe 3+ content, the NIR light response shape recovery rate of PUTA/Fe composite films is significantly improved, and the shape recovery time is reduced from over 60 s to 40 s. In addition, the mechanical properties of PUTA/Fe composite film are also improved. Importantly, owing to the dynamic phenol–carbamate network within the polymer matrix, the PUTA/Fe composite film can reshape its permanent shape through topological rearrangement and show its good NIR light response shape memory performance. Therefore, PUTA/Fe composites with high content of bio‐based material (TA content of 15.1–19.4%) demonstrate the shape memory characteristics of fast response to NIR light; so, it will have great potential in the application of new intelligent materials including efficient and environmentally friendly smart photothermal responder.