Research on HV-PA-based composite microgel coatings for the temporary protection of unearthed bronze ware

Limited research exists on the temporary protection of unearthed bronzes during transportation to museum environments. An eco-friendly protective coating for bronzes featuring corrosion inhibition, reinforcement, and nondestructive peeling was developed. The HV-PA+ L -Arg composite microgel was prepared by mixing polyvinyl alcohol/polyethylene glycol diacrylate microgel (PA) with l -arginine-containing pre-crosslinking solution (HV) followed by centrifugation. Results from colorimetric analysis showed that the composite microgel did not alter the appearance of bronzes. Electrochemical impedance spectroscopy revealed a corrosion inhibition efficiency of up to 95.72 %. The corrosion inhibition mechanism was analyzed using X-ray photoelectron spectroscopy, Raman spectroscopy, density functional theory, and molecular dynamics simulation. Compression and tensile tests quantified the reinforcement of HV-PA-based composite microgels before and after cross-linking, demonstrating that compressive strength increased by approximately 2.70-fold and tensile strength by 2.27-fold. Reinforcement mechanisms were analyzed using rheological tests and scanning electron microscopy (SEM). The nondestructive stripping performance of the HV-PA+ L -Arg composite microgel was characterized by scanning electron microscopy/energy dispersive X-ray spectroscopy and Raman. Nondestructive stripping, achievable via ethanol spraying and ultraviolet (UV) irradiation, offers dual options for flexible removal of the protective coating, ensuring subsequent restoration or reprocessing of bronze relics.