Abstract: The synergetic flame-retardant effect and mechanism of brominated epoxy resin (BER) and antimony trioxide（Sb2O3）for PET were studied via measuring vertical combustion performances (UL94), physical performances, and smoke release. CONE data showed that the PET system passed ULV-0 test, the smaller the particle size of Sb2O3, the better the flame-retarding effect. However, the BER/ Sb2O3 system was poor on the suppression of smoke effect and its av-SEA, SPR, and av-CO increased. With BER and Sb2O3 introduced, PET exhibited increased melt flow rate, higher Vicat softening point, smaller parallel and vertical injection mold shrinkage, higher shore D hardness, and larger flexural strength and flexural moduli, but lower notched impact strength, elongation at break, and tensile strength. FTIR and gas chromatography (Py-GC) analysis showed that the residue char of pure PET and flame-retarded PET was not complete the same; the retention time of main peak was different indicative that the BER/ Sb2O3 system had flame-retarded effects not only in gas phase but also in solid phase.

Key words: brominated epoxy resin, antimony trioxide, combustion property, mechanical property, poly(ethyleneglycol terephthalate), fire retardant property