Preparation of Ca[B6O9(OH)2] · 3H2O nanomaterials by a phase transformation method and their flame retardant and thermodynamic properties

Ca[B6O9(OH)2] · 3H2O nanoflake has been prepared by an ultrasound-assisted phase transformation of ulexite in H3BO3 aqueous solution. The nanoflake sample with smaller size had better flame retardant property than others, which was investigated by a thermal analysis method.