Synthesis of novel high-performance all-biobased wood flame retardant materials using phytic acid and β-cyclodextrin

This research synthesized a novel all-biobased, highly flame-retardant and smoke-suppressing flame retardant through the reaction of ammonium phytate (PAAn) and succinic acid-modified β-cyclodextrin (SA-β-CD). In the synthesis process, only deionized water was used as the solvent, conforming to the current requirements for eco-friendly approaches. The results showed that under the synergistic effect of PAAn and SA-β-CD, the thermal stability and flame retardancy of the wood were significantly enhanced. Thermogravimetric analysis (TG) indicated that the char yield of the PAAn-SA-β-CD2@DW reached 40.24 %. The peak heat release rate (PHRR) and total heat release (THR) were reduced by 91.78 % and 84.41 %. The PAAn-SA-β-CD2@DW sample was not ignited in the cone calorimeter test, and its fire growth index (FGI) value was only 0.094 kW/m 2 ·s, which was 97.37 % lower than that of the untreated wood. The synergistic effect of PAAn and SA-β-CD was found to promote the formation of non-combustible gases, and the generation of a dense protective char layer on the wood surface during combustion. This inhibits the diffusion of oxygen and heat, imparting the significantly improved fire resistance to the treated wood. This study provides a simple and eco-friendly synthesis approach, which broadens the scope of application of phytic acid and β-cyclodextrin.