The research proves that intumescent coatings with alkaline lignin have superior flame retardancy compared to those without additives. Based on this information, intumescent water-based coatings containing 5% alkaline lignin significantly improved the flame retardancy by promoting the formation of an ideal char layer during combustion.

The study investigated the flame retardancy of water-based intumescent coatings for plywood by conducting flame retardancy tests by using water-based acrylic resin mixed with various concentrations (1%, 3%, 5%, and 10%) of alkaline lignin. Intumescent coatings containing alkaline lignin demonstrated superior flame retardancy compared with those without additives. At a concentration of 5%, the alkaline lignin promoted the formation of an ideal char layer during combustion.