Effects of flame retardants on liquid oxygen compatibility of epoxy resin containing binaphthyl based on combination of mechanical impact testing and theoretical analysis

The epoxy resin containing binaphthyl (BEBN) was synthesized, and the curing process of BEBN by amidogen curing agent was investigated. The hexabromocyclododecane, antimony trioxide, decabromodiphenyl oxide, and aluminum hydroxide were added to the BEBN in order to improve the compatibility of BEBN with the liquid oxygen. The compatibility of cured BEBN was evaluated by mechanical impact according to ASTM D-2512-95 standard. The microstructure and the surface element compositions of the specimen before and after the mechanical impact were investigated and analyzed by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. The mechanical impact results confirmed that the compatibility of BEBN with liquid oxygen was related to the oxidation reaction, and the compatibility was significantly improved after adding the flame-retardant additives, specially the combination of the inorganic and organic additives.