Research on preparation of nano-Sb2O3@Br-VERs core-shell composite particles

Nanoparticles with core-shell structure provide a new potential technology to improve the efficiency of flame retardants. Using nanometer antimony trioxide particles (nano-Sb2O3) as matrix material and brominated bisphenol-A epoxy vinyl ester resin (Br-VERs) diluted by toluene (PhMe) or styrene (ST) as the coating material, PhMe-nano-Sb2O3@Br-VERs and ST-nano-Sb2O3@Br-VERs core-shell composite particles were prepared by electromagnetic stirring method. The results show that Br-VERs can successfully coat on the surface of nano-Sb2O3, thus forming core-shell composite particles with crystalline nano-Sb2O3 as the core and amorphous Br-VERs as the shell. The thickness of Br-VERs shell of PhMe-nano-Sb2O3@Br-VERs composite particles is between 9.5 nm and 15.5 nm, and the shell's mass fraction is 20.8% in the composite particles. The thickness of Br-VERs shell of ST-nano-Sb2O3@Br-VERs composite particles is between 5.5 and 9.5 nm, and the shell's mass fraction is 3.8%. The mass of Br-VERs shell of PhMe-nano-Sb2O3@Br-VERs composite particles is 5.47 times that of ST-nano-Sb2O3@Br-VERs composite particles, which indicates PhMe used as the diluent for Br-VERs has a better effect than that of ST used as the diluent.