A Novel Self-Healing Polyurethane with High Transparency and Strength: Effects of Multiple Supermolecular Forces

It is a considerable challenge for expanding the applications of self-healing polyurethane because of the dilemma in balancing its mechanical and self-healing properties. Herein, a series of self-healing polyurethane systems (PUT-x) with short-range ordered rigid aromatic structures were synthesized by simply adjusting two kinds of diisocyanates, and by ingenious addition of aromatic chain extender. We hope to regulate the π-π interactions and further to manipulate the properties of obtained polyurethanes via adjusting the amount of the benzene rings in the molecular chains of the PUT-x systems. The PUT-5 with decent self-healing ability, optimal mechanical properties, acceptable thermal stability and favorable transparency was selected to incorporate liquid metal and fluorescent powder to fabricate conductive wire and anti-counterfeiting film. Significantly, the liquid metal could be recycled from the conductive wire conveniently without using strong acids or strong bases. Moreover, PUT-5 exemplarily withstood long-term soaking in normal saline, and no deformation could be identified.