Preparation of polymers possessing dynamic N-hindered amide bonds through ketene-based chemistry for repairable anticorrosion coatings

Dynamic covalent bonds, particularly the ones exhibiting bond-breaking and bond-regeneration under ambient conditions, are attractive for the design and application of smart materials. This study demonstrates that the Meldrum's acid-based ketene chemistry is an effective approach to build up dynamic N-hindered amide bonds effectively workable at ambient conditions and under sunlight. The corresponding polyamides have been applied for sunlight-driven and self-repairing polymeric materials, and anticorrosion coatings. In addition to exhibiting sunlight-driven and self-repairing features on scratched surfaces, a high anticorrosion recovery of about 97% has been recorded. A smart anticorrosion coating requiring less maintenance is demonstrated. Ketene chemistry-based dynamic covalent amide bonds is applied for sunlight-driven and self-repairing polymers and antiicorroison coatings.