Synthesis of a deoxybenzoin derivative and its use as a flame retardant in poly(trimethylene terephthalate)

A Friedel-Crafts acylation reaction was used to synthesize a deoxybenzoin derivative named bis[2,6-dimethyl-4-(2-phenyl acetyl) phenyl] phenyl phosphonate (BDPP), which could be used as a flame-retardant additive in poly(trimethylene terephthalate) (PTT) resin. The limited oxygen index and cone calorimetry tests indicated that the introduction of 5 wt % BDPP significantly improved the flame-retardant properties of PTT through a synergistic char-formation mechanism in the condensed phase and a flame-inhibition mechanism in the gas phase. The PTT-BDPP blend also demonstrated an evident reduction in the melt viscosity but a superior melt stability in comparison to the neat PTT. (C) 2017 Wiley Periodicals, Inc.