PIN mineral salts and water-borne epoxy were used to fire safety treat wood, reducing flammability and fire gas toxicity. Fire safety is critical to enable use of wood as a renewable carbon-sink material for green building. PIN mineral salts, with good environment profiles, sodium silicate and aluminium sulphate, with water-borne epoxy, were impregnated into poplar wood by 2-step pressure/vacuum immersion. This resulted in double oxide layers within the wood. The water-borne epoxy (with triethanolamine curing agent) was used to reduce mineral losses from the wood. Total loading in the wood was 40% w/w. Peak heat release rate was reduced by around 40%, peak smoke release by around 35% and peak carbon monoxide release by nearly 75%. Toxic smoke gas emissions such as ketones were also significantly reduced. The authors conclude that this is an environmentally friendly fire safety treatment of wood, enabling low smoke and toxic gas emissions in fire.
“Synergistic effects of Al/Si double oxide on flame-retardant and smoke-suppressant wooden materials”, Z. Sun et al., J. Building Engineering 59 (2022) 105037 https://doi.org/10.1016/j.jobe.2022.105037