Investigation on Corrosion Behavior of Polydimethylsiloxane and Nanofillers-Based Polymer Nanocomposite Coated Galvanized Iron

Abstract

The paper focuses on developing polydimethylsiloxane (PDMS) and nanofillers (ZnO and SiO<inf>2</inf>) based polymer nanocomposite solutions for coating galvanized iron (GI) using sol–gel dip coating method and investigating its corrosion behavior. The nanofillers in varying wt.% (0, 2, 4, 6, 8, and 10) are incorporated in the solution of PDMS and xylene for developing a nanocomposite coating solution. The solutions are characterized by pH, viscosity, and non-volatile matter. It is observed that all the solutions are basic. The viscosity (10.28–47.43%) and the non-volatile matter (8.06–15%) of the solutions are observed to be increasing with an increasing nanofiller % as compared to the base solution (PDMS and xylene). The developed solutions are coated on the GI substrate and tested for wettability, XRD, FTIR, and electrochemical responses. The wettability and the XRD tests confirm the hydrophobic and amorphous nature of the coated surface, respectively. The Si–O–Si groups are observed at 1088 cm−1. The electrochemical analysis shows that the impedance resistance of the coated surfaces is higher than that of the surface coated with the base solution. Further, the corrosion rate of the coated surfaces decreases with the % of the nanofillers. The coating with 10% nanofillers exhibited the highest impedance resistance and the lowest corrosion rate, finding applications in construction, marine, and naval. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.