Abstract: PET-MCA composites (PET-MCA) and phosphorus-contanining poly(ethylene terephthalate) (CP-PET)-MCA composites (CP-PET-MCA ) were prepared by melamine cyanurate (MCA) and poly(ethylene terephthalate) (PET) and CP-PET. The thermal stability, flame retardancy and char forming characteristics of the product were investigated by TGA, LOI, UL-94, Cone Calorimeter, SEM and EDS, and the mechanism were discussed. The result suggested that the temperature of thermal decomposition of PET and CP-PET showed a slight decrease with the incorporation of MCA, and the mass of residual char and LOI increased. CP-PET reached V-0 rating standard from UL-94 test and more uniform char granules were acquired. The addition of MCA compounded with 2-carboxyethyl(phenylphosphinic) acid (CEPPA) imparted N-P synergism effect on the flame retardancy of PET.

Key words: phosphorus-containing poly(ethylene terephthalate), melamine cyanurate, N-P synergism, flame retardancy