Flame retardancy effects on intumescent coatings with vinyl acetate copolymers

This research aimed to study the effects of fire combustion on materials coated with ethylene vinyl acetate and polyvinyl acetate copolymer emulsion resins with differing foam producing substance to dehydrating agent ratios. The flame retardancy of these materials was assessed by evaluating their heat release, CO and CO2 emissions. Experimental results indicate that intumescent paint formulations significantly enhance the flame retardancy of painted plywood, thus reducing peak heat release rate and extending the time to reach peak heat release rate. Moreover, a low amount of foam producing substance enhances the fire retardancy of plywood panels. Furthermore, binder resin containing vinyl acetate monomer in intumescent coatings can enhance fire performance. In addition, low foam producing substance content can form an ideal char layer, which significantly reduces CO and CO2 emissions. The mechanism to achieve more favorable fire performance was verified by carrying out thermogravimetric analysis, which demonstrated lower weight loss. The results of this study provide an improved understanding of the effects of intumescent coatings.