Researchers have made a groundbreaking discovery in the field of coating technology, finding that the use of PA/ZnO hybrid nanoparticles can provide effective protection for metal substrates against fire-related damage. These hybrid nanoparticles, developed using a layer-by-layer approach, combine the flame-retardant properties of phytic acid (PA) and zinc oxide (ZnO) on a nanoscale scaffold.
When incorporated into polyurethane (PU) coatings at a concentration of 20 wt%, the PA/ZnO nanoparticles did not compromise the physical or mechanical properties of the coatings. In fact, the coatings showed a significant improvement in flame-retardant properties compared to coatings without nanoparticles.
Flame spread rate tests demonstrated a 50% reduction in flame spread rate for PU samples containing the PA/ZnO nanoparticles compared to samples with only ZnO nanoparticles. Furthermore, cone calorimeter studies on metal panels coated with the nanoparticle-infused PU resins showed a 25% reduction in peak heat release rate and a 50% reduction in total heat release, highlighting the effectiveness of the coatings in preventing the spread of fire.
Scanning electron microscopy images revealed the formation of char and bubble-like structures in the burnt samples containing the nanoparticles, indicating their ability to obstruct escaping gases during the burning process. This research, published in the Journal of Coatings Technology and Research, offers promising insights into the development of fire-resistant coatings for metal substrates.