Poly(bisphenolA phenylphosphonate)(PBPPP) was synthesized by melt polycondensation using phenylphosphonic dichloride(PPD) and bisphenol A(BPA). The relationships between inherent viscosities of PBPPP and reaction conditions such as temperature

time

ratios of monomers and the ways of addition were shown in the paper. The inherent viscosities of PBPPP increased with the increase of ratios of BPA/PPD

the reaction temperature and time

but they behaviored opposite varrations when the ratio of BPA/PPD

the reaction temperature and time

but they behaviored opposite varrations when the ratio of BPA/PPD

the reation temperature and the reaction time were beyond 1:0.990

280℃ and 4.5h

respectively.PBPPP products with an inherent viscosity of 0.37g/dL were obtained in the optimum conditions in which the ratio of monomers was 1:0.99(-OH/-Cl)

the reaction temperature from 160℃ to 280℃ and the time 4.5h.The structures of PBPPP were characterized by FT-IR

1H-NMR

31P-NMR and elemental analysis.The thermal behavior was evaluated by DSC and TG. The thermal analysis indicated that the Tg of PBPPP was at 107℃ and PBPPP's starting loss weight at about 310℃.The LOI of PET containing 10wt% PBPPP was 28.0

which show that PBPPP can be used as flame retardants.