LOW-FLAMMABILITY WOOD-POLYMER COMPOSITES MODIFIED WITH BROMINATED NOVOLAC CARDANOL RESIN

This study investigated the fire-retardant efficacy of brominated novolac cardanol resin in wood-polymer composites based on low-density polyethylene. The high flammability of traditional wood-polymer composites limits their use in construction, necessitating the search for renewable flame retardants. Composites with brominated novolac cardanol resin contents ranging from 0 to 12.5 wt. % were manufactured using rolling and hot-pressing methods. The fire retardant performance of brominated novolac cardanol resin was assessed based on mass loss, burnt-out length, flame propagation velocity, the presence of burning droplets, and the structural integrity of the sample. The optimal modifier concentration was found to be 9.6 wt. %. Moreover, mass loss is reduced from 65 to 6.8 %, the damaged zone length is shortened from 150 to 5.5 mm, and the flame propagation rate is reduced from 28.6 to 9.7 mm/min. The formation of burning droplets and sample failure is completely eliminated. The study results confirm the high  effectiveness of brominated novolac cardanol resin as an environmentally friendly flame retardant for the creation of fire-resistant wood-polymer composite materials.