Synergistic Effect of Nanosilica Aerogel with Phosphorus Flame Retardants on Improving Flame Retardancy and Leaching Resistance of Wood

Table 1

Formula of impregnation experiment for untreated and treated wood.

Samples	H2O	APP	DAP	AP	SiO2 sol
S0	Y	N	N	N	N
S1	N	Y	N	N	N
S2	N	N	Y	N	N
S3	N	N	N	Y	N
S4	N	Y	N	N	Y
S5	N	N	Y	N	Y
S6	N	N	N	Y	Y

Note. Y is short for Yes. N is short for No.