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

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.