超支化聚磷酸酯阻燃剂对尼龙6的成炭促进作用

以三氯氧磷和双酚A为原料制备了具有超支化结构的聚磷酸酯阻燃剂(HPPEA),通过红外(FTIR),核磁(1H-NMR,31P-NMR)及热重分析表征了产物的结构和热稳定性.将HPPEA与三聚氰胺聚磷酸盐(MPP)进行复配,通过熔融共混法制备阻燃尼龙6,通过氧指数法和垂直燃烧法测试了其阻燃性能,采用热重分析(TGA)研究...

PROMOTION EFFECT OF A HYPERBRANCHED POLYPHOSPHATE ESTER FLAME RETARDANT ON CHAR FORMATION OF POLYAMIDE 6

A hyperbranched polyphosphate bisphenol-A ester flame retardant(HPPEA) was prepared by using phosphorus oxychloride and bisphenol-A.The structure and thermal stability of the product were characterized by Fourier transform infrared spectrometer(FTIR),nuclear magnetic resonance spectrometer(1H-NMR,31P-NMR) and thermogravimetric analysis(TGA).Branching degree of HPPEA determined by 31P-NMR spectrogram was about 51%.HPPEA combined with melamine pyrophosphate(MPP) was incorporated into polyamide 6(PA6).The flame retardant and thermal properties of the flame retardant PA6(FR-PA6) were studied through limiting oxygen index(LOI) and UL-94 vertical burning and TGA tests.The results showed that the LOI for flame retardant PA6 was improved to 27.3 from 21.1 for PA6,and UL-94 V-0 rating was achieved with 20 wt% flame retardant.According to TGA results,the char yield of FR-PA6 at 600℃ was also increased to 16.4 wt% in air atmosphere and 13.6 wt% in N2.Combining with the study of kinetics of thermal degradation and complex viscosity of FR-PA6 samples,clearly synergistic effect existed between HPPEA and MPP,which improved cross linking and char forming of PA6.Furthermore,morphology of char residues of FR-PA6 samples was also investigated by SEM method.Honeycomb and compact char layer was found which effectively protects the internal structure,inhibits the heat transmission and reduces the fuel gas during combustion.