In situ preparation and formation mechanism of 2MgO·B2O3·1.5H2O–Mg(OH)2 nanocomposite and its synergistic flame retardancy

It has demonstrated that there are major advantages and synergistic effects on flame retardancy in using a combination of borates with magnesium hydroxide. In this paper, a novel 2MgO·B2O3·1.5H2O–Mg(OH)2 nanocomposite has been controllably prepared by in situ hydrothermal reaction, and the formation mechanism of the nanocomposite was proposed. As a comparison, 2MgO·B2O3·1.5H2O nanobelt and Mg(OH)2 nanosheet were also prepared. All samples were characterized by XRD, FT-IR, TG, SEM, TEM and HRTEM. Furthermore, their flame-retardant properties were investigated by thermal analysis method and oxygen index method, demonstrating that the flame retardancy of nanocomposite is significantly higher than that of single 2MgO·B2O3·1.5H2O or Mg(OH)2. The possible flame retarding mechanism has been proposed. It can be predicted that this nanocomposite could serve as a potential flame retardant.