In-situ construction of BiOCl@Cu-MOF for synergistic flame retardancy, smoke suppression, and antibacterial properties in PVC coatings

As one of the most widely utilized polymer coating systems, polyvinyl chloride (PVC) is extensively applied in industrial protection fields due to its excellent processability and cost efficiency. To meet rising performance demands in extreme environments, developing PVC coatings with efficient flame retardancy and smoke suppression has become a key research focus. This study developed an innovative BiOCl@Cu-MOF hybrid through an in situ growth strategy. Incorporating the additive at 15 phr increased the limiting oxygen index (LOI) from 23.4 % to 29.4 %. The PVC coating also passed the UL-94 rating test, reaching the highest V-0 level. Cone calorimetry analysis showed a 55.9 % reduction in peak heat release rate, indicating superior flame retardant behavior. In terms of smoke suppression, the coating achieved a 66.7 % decrease in peak smoke production rate. More importantly, the peak carbon monoxide production, a critical lethal factor in fires, was suppressed by 46.9 %. The PVC coating further exhibited 99.9 % antibacterial efficacy against both Staphylococcus aureus and Escherichia coli . This work establishes a pioneering design paradigm for multifunctional protective coatings, offering significant potential in fire-safe building materials, electronics encapsulation, and bio-secure applications.