SiO2-P2O5-B2O3 wood-inorganic composites prepared by metal alkoxide oligomers and their fire-resisting properties

SiO2-P2O5B2O3 wood-inorganic composites from metal alkoxide monomers revealed a high fire-resistance, whereas these composites have some problems in the stabilities of P2O5 and B2O3 gels as well as environmental safety for their preparation. Therefore, some silicon alkoxide oligomers with ethylphosphite residue and/or boric hydroxide residue were prepared and applied for SiO2-P2O5-B2O3 wood-inorganic composites preparation. The obtained composites could have high fire-resistance and prevent these gels from leaching. Additionally, the prepared oligomers are non-toxic so that the environmental safety for their preparation was achieved. By adding 2-heptadecafluorooctylethyltrimethoxysilane (HFOETMOS) to the oligomer reaction system, the obtained composites could improve further the anti-leachability of P2O5 and B2O3 gels.