| A novel phosphorous-nitrogen bifunctional curing agent BPAN with flame retardancy was synthesized and characterized by Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance (NMR). The thermal stability of BPAN was investigated by thermo gravimetric analysis (TGA), FTIR and Raman spectrum. Then, the properties of diglycidyl ether of bisphenol A (DGEBA) epoxy polymer cured by BPAN alone or mixed BPAN with diamino diphenyl sulfone (DDS) were investigated. The DGEBA/BPAN system showed that a higher LOI value of 30 and passed UL 94 V0 rating (1.6mm) compared with control system of DGEBA/ DDS. The char yield at 600℃was also increased to 21.6% compared with the control system. Meantime, the peak value of heat release rate of DGEBA/BPAN reduced by 42% compared to the control system in the pyrolysis combustion flow calorimetry (PCFC) test.In order to improve the comprehensive properties of epoxy polymer, the effects of nano fillers such as nano clay and nano silica on epoxy polymer were also investigated by TGA, LOI, UL 94, DMA and Raman spectrum. The nano clay could shorten the burning time of epoxy polymer in UL 94 rating test. When the loading was 2wt%, the epoxy nanocomposite reached higher LOI value of 31. The organic modified nano silica improved the compatibility between epoxy polymer and nano silica, however the flame retardancy and thermal property were lower than pure epoxy polymer. |
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