Abstract: Poly(methylphosphitebisphenol A ester) oligomer(PMPBE) was obtained by melt condensation polymerization of methylphosphonous dichloride and bisphenol A. The structure of PMPBE and the properties of epoxy resin(EP)/PMPBE blends were characterized with Fourier transformed infrared spectrum(FTIR), nuclear magnetic resonance spectroscope, thermogravimetric analyzer(TGA), differential scanning calorimeter(DSC), vertical burning tester,limited oxygen index tester, and micro-scale combustion calorimetry. Adding 20 phr of PMPBE, the limiting oxygen index of EP was increased from 19 % to 27.6 % and the sample passed the UL94 V-0 rating, the heat release capacity and heat release rate reduced by about 27 %.TGA results showed that the char yield at 700 ℃ increased obviously compared with the neat EP. Moreover, PMPBE had little influence on the mechanical properties of EP.

Key words: Polyphosphonate, melt condensation polymerization, flame retardant, epoxy resin