Ultrafast and high-efficient self-healing epoxy coatings with active multiple hydrogen bonds for corrosion protection

Combining a fast self-healing action and a high barrier property remains a challenge in polymeric protective coatings. Herein, we report an intrinsic self-healing epoxy coating in which 2-ureido-4[1H]-pyrimidinone (UPy) as a quadruple hydrogen bonding unit, grafted onto the backbones of an epoxy-matrix by an amine-terminated oligo(propylene glycol) linker. Without any intervention, the epoxy-matrix performs its self-healing function in similar to 5 min, even under aqueous immersion. Besides, electrochemical impedance spectroscopy measurements demonstrate corrosion protection ability of such self-healed coating on a steel substrate, with a high vertical bar Z vertical bar(0.01Hz) value of 4.8 x 10(10) Omega.cm(2) after 60 days of immersion in NaCl solution.

Automated summary

An intrinsic self-healing epoxy coating containing 2-ureido-4[1H]-pyrimidinone (UPy) as a quadruple hydrogen bonding unit demonstrates fast self-healing and high corrosion protection properties on a steel substrate, even after 60 days of immersion in NaCl solution.