An anti-corrosion coating with self-healing function of polyurethane modified by lipoic acid

Polyurethanes (PUs) are a polymer material with a wide range of applications and excellent mechanical properties. In this work, a modified polyurethane coating with the self-healing function is developed via the reaction between polytetrahydrofuran (PTMG), 2,4-toluene diisocyanate (TDI) and α-lipoic acid. The coatings are characterized by SEM and FTIR. The protection of the prepared coating for copper in 3 wt.% NaCl solution is investigated by the electrochemical measurements and the surface self-healing tests. The coating has stable protection from corrosion of the copper substrate in corrosive medium and shows a good self-healing ability. The healing behavior in morphology and corrosion resistance can be observed when heated above 60°C. Graphical abstract