Fabrication of multifunction polyurethane with robust, self-healing and anti-corrosion performance based multiple dynamic bonds strategy

Polyurethanes (PUs) containing multiple dynamically have been extensively studied, however combining their mechanical, self-healing and anti-corrosion ability remains a significant challenge. Therefore, this paper successfully prepared PU coating (PU-SS-Salen-Ni) by introducing Ni2+ coordinated Salen and bis(4-hydroxyphenyl) disulfide chain extenders. PU-SS-Salen-Ni with quadruple dynamic bonding exhibited excellent tensile strength (15.4 MPa), toughness (72 MJ·m−3) and superior self-healing efficiency (86.8 %) after being held at 80 °C for 4 h. Meantime, the |Z|f=0.01Hz of PU-SS-Salen-Ni coating reached at 9.35 × 106 Ω·cm2 at the beginning of immersion, and even maintained at 6.99 × 106 Ω·cm2 after 28 days immersion due to the synergistic effect of multiple dynamic bonds. This study provides insight into the design of PU elastomers with sustainable self-healing, excellent mechanical properties and corrosion protection.