Enhanced flame-retardant property of epoxy composites filled with solvent-free and liquid-like graphene organic hybrid material decorated by zinc hydroxystannate boxes

A polyether amine (M2070) was covalently grafted onto the surface of graphene nanosheets (GNS) decorated by zinc hydroxystannate boxes (ZHS) to obtain an organic hybrid material (GNS-ZHS-M2070) with solvent-free and liquid-like behavior. It was subsequently incorporated into epoxy resin (EP) to investigate the flame-retardant property. The GNS-ZHS-M2070, which was a homogeneous sticky fluid at room temperature without any solvent, could stably disperse in a broad spectrum of solvents. Most importantly, the GNS-ZHS-M2070/EP composites possessed superior flame-retardant performance, such as the lowest peak heat release rate and fire growth rate index values. Furthermore, it had been demonstrated that the superior flame-retardant performance of GNS-ZHS-M2070/EP should be ascribed to the excellent processability and good compatibility of GNS-ZHS-M2070 derived from the unique flowability and soft organic shell. All of these advantages along with the solvent-free nature of GNS-ZHS-M2070 provided a green, efficient and environment-friendly way to fabricate high flame-retardant performance composite materials.