| Bisphenol A polycarbonate (PC) and poly(butylene terephthalate) (PBT) are easily blended to form PC/PBT blends,exhibiting promising impact strength, workability, chemical resistance and excellent insulation property to be widely used in such fields as sports requisites,outdoor manufacturers,electrical and electronic devices, automobiles and constructions. Flame resistance is a key property for applications in these fields, but few attentions have been given for the flame-retardant improvement of PC/PBT blends.Compared with halogen flame retardants,phosphrus flame retardants produce less poisonous, corrosive gas,working both in condensed phase and gaseous phase,having a high efficiency flame retardants. Some ligomeric aryl phosphates like resorcinol bis(diphenyl phosphate) (RDP), bisphenol A bis(diphenyl phosphate) and triphenyl phosphate were found to be efficient in readily charrable PC[3].PC/ PBT blends was improved by RDP and poly(phenylene ether) (PPO). A PC/PBT blend at 70/30 weight ratio passed a V-0 rating by the adddition 10 wt% RDP and 10 wt% PPO. The combination of 5 wt% methyl methacrylate-butadiene- styrene tercopolymer (MBS) with 3 wt% ethylene-butylacrylate-glycidyl methacrylate tercopolymer (PTW) causes a remarkable increase in toughness of the PC/PBT/RDP blend maintaining a high rigidity. A detailed investigation to flame-retarded mechanisms of PC/PBT/RDP and PC/PBT/RDP/PPO blends was performed by thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) , TGA-FTIR , temperature-programmed pyrolysis/gas chromatography/mass spectrometry (TPPy/GC/MS) and scanning electron microscopy/energy dispersive spectrometer (SEM/EDS). The results demonstrated that RDP induced a higher char yield at 450 oC and synchronously increased the thermal stability of the blend with PPO which were responsible for high flame-retarded ratings of the blends. The paper provides a crucial foundation for outlining the potential future direction of this field.
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