pH-Sensitive Siloxene-based Composite Materials Endow the Epoxy Coating with Efficient Self-Healing Function and Excellent Mechanical Properties.

The long-term corrosion resistance of metal coatings remains a persistent challenge. Single nanofillers often fail to address this issue comprehensively. Herein, siloxene (S) was employed as a substrate to construct a composite structure integrating polyaniline (PANI) and Ce-MOF. The PANI structure imparts passive corrosion protection to the coating, while the pH-responsive Ce-MOF structure endows the coating with efficient self-healing capability. In addition, the fibrous PANI and the unique flexible structure of Ce-MOF endow the two-dimensional S sheets with good load-bearing capacity, thus enabling the composite coating to exhibit enhanced mechanical properties, which include adhesion strength, tensile performance, and wear resistance. It is found through research that the |Z|0.01 Hz of the composite coating increases by 1.5 orders of magnitude in the initial stage of immersion, and the tip current value decreases by more than 80% after being immersed for 20 days. A more than 80% decrease in wear rate is observed in the composite coating, and the adhesion, tensile strength, and tensile modulus of the coating are significantly improved. This study offers significant perspectives on the development of versatile nanofillers for epoxy coatings and establishes an application strategy for S materials in metal coating systems.