Flame retardant effect of lignin/carbon nanohorns/potassium carbonate composite flame retardant on fir pretreated under different methods

Fir wood is widely used in construction, however its thermal degradability and flammability pose significant challenges to its safe use. In this work, we used a new carbonaceous nanomaterial called single-walled carbon nanohorns (SWCNHs), in combination with lignin and potassium carbonate to prepare a composite flame retardant and investigated the effect of different pretreatments on the flame retardant effect of fir wood. After delignification pretreatment and vacuum impregnation of fir wood with the flame retardant, the pk 1 -HRR and the pk 2 -HRR decreased by 37.59 % and 25.07 %, THP decreased by 55.71 %, TSP decreased by 59.81 %, COP significantly decreased by 74.02 %, char residual weight increased by 14.11 % compared with new wood (NW), and LOI reached 28.8 %. And the composite flame retardant forms a char layer during burning, which acts as a protective layer. This provides new insights into the application of SWCNHs in wood flame retardancy.