Scratch and mar resistance of PU/Al2O3 on automotive clearcoats

Abstract

In this study, polyurethane was combined with experimentally synthesized nano-alumina particles to form coatings. Nano alumina was synthesized by the sol-gel method. The polyurethane's scratch and abrasion resistance was greatly increased by the inclusion of nano-alumina, making it appropriate for use in automotive applications. The appropriate dispersion and functionalization of nano-alumina particles inside the polyurethane matrix were achieved by careful consideration of the coating's production process, which was detailed in detail. The properties and efficiency of the nano-alumina coatings were confirmed using a variety of characterization techniques, including XRD, FTIR, SEM, and contact angle analysis. XRD analysis showed the formation of nano alumina by specific peaks and card number was matched using expert high score. In comparison to non-functionalized particles, the research findings showed that functionalizing nano-alumina with stearic acid improved stability, hydrophobicity, and scratch resistance. XRD and FTIR data showed successful functionalization of nano alumina with steric acid. When used on a mild steel substrate, the resulting polyurethane-nano alumina coating showed good dispersion and greatly increased abrasion resistance and water repellency. The scratch tests revealed that the coating offered reliable defense, particularly against fine abrasives. The successful incorporation of the nanoparticles was confirmed by the SEM examination, which produced visible proof of the uniform distribution of nano-alumina particles within the polyurethane matrix. The well-adhered and compact coating structure was also visible in the SEM images, demonstrating the close interfacial bonding between the polyurethane and functionalized nano-alumina. Keywords: Coatings, Nano alumina, Polyurethane, Hydrophobicity, Scratch Resistance