Development of supramolecular shape-memory polyurethanes based on Cu(II)-pyridine coordination interactions.

Shape-memory polymers with supramolecular switch have received increasing attention. This study reports the synthesis and characterization of supramolecular shape-memory polyurethane based on Cu(II)-pyridine coordination, obtained by mixing pyridine containing polyurethane with CuCl2. The results show that there are strong metal-ligand coordination interactions formed between Cu(II) and the pyridine ring in a series of CuCl2-doped polyurethane samples. The Cu(II)-pyridine coordination plays a crucial role in the enhanced physical netpoints for outstanding shape-memory properties. Indeed, the so-synthesized CuCl2-doped polyurethane exhibits not only a rapid tensile shape recovery but also excellent crimp shape recovery. The CuCl2-doped polyurethane containing suitable metal-ligand coordination interactions shows more than 99% shape fixation and more than 95% shape recovery. Our findings promote further applications of shape-memory polymers in multiple engineering fields. [ABSTRACT FROM AUTHOR]