Improved anticorrosion, flame retardant and mechanical behaviors of multifunctional polyurethane nanocomposite coatings for industrial applications

Abstract

The anticorrosion, flame retardant, and mechanical properties of polyurethane (PU) coatings have been enhanced by the inclusion of zirconium disulphide (ZrS2), 2-mercapto-5-(methoxy)-1,3,4-thiadiazole (MMTD), and graphene oxide (GO). The structural and morphological behaviours of the films for the different coating formulations were investigated using SEM/EDX (Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy), TEM (Transmission Electron Microscopy), TGA (Thermogravimetric Analysis), XPS (X-ray Photoelectron Spectroscopy), and XRD (X-ray Diffraction) analysis. With the inclusion of just 0.3% GO/MMTD-ZrS2, the dielectric constant of PU at 1 Hz was increased by 85 times. Additionally, when compared to plain PU, the PU-GO/MMTD-ZrS2 demonstrated increased flame retardancy with significant decreases in the peak heat release rate (pHRR) and total heat released (THR), or reductions of 65% and 52%, respectively. The addition of GO/MMTD-ZrS2 compound to the PU matrix improves the PU coating's anticorrosive, hydrophobic, flame retardancy, and mechanical performance. The hyper hydrophobic behavior is verified by its water contact angle (WCA), which is 168˚. Additionally, it was discovered that PU-GO/MMTD-ZrS2 had considerably higher coating resistance (20,997.1 kΩ.cm2) compared to the other coatings under investigation. PU-GO/MMTD-ZrS2 was found to have a microhardness of 1355 MPa and a binding strength of 17.9 MPa, respectively. This means that the PU-GO/MMTD-ZrS2 nanocomposite could be applied in industrial settings as a coating substance.