多糖生物质/聚磷酸铵协效阻燃环氧树脂∗

Synergistic Effects of Polysaccharide Biomass and Ammonium Polyphosphate on the Flame Retardancy of Epoxy Resin

为了提高环氧树脂的阻燃性能,本文选用了具有多糖结构的2种生物质壳聚糖(Cs)和淀粉(St),与聚磷酸铵(APP)复配协效,研究多糖生物质与APP协效阻燃体系对环氧树脂(EP)阻燃性能的影响。文中采用极限氧指数、垂直燃烧、锥形量热、热重分析、扫描电镜和拉曼分析等对体系进行阻燃研究。结果表明,与仅添加相同量的APP相比,多糖生物质与APP协效阻燃体系对环氧树脂阻燃效果显著,当APP与壳聚糖或淀粉的质量分数比分别为12∶2或13∶1时,阻燃协效作用最佳,极限氧指数从只添加APP的26.7%分别提高到28.2%和28.4%,燃烧等级从HB等级提高到V-0级;燃烧热释放速率峰值和热释放总量均降低;CO和CO_(2)排放明显降低;残炭量明显增加,残炭更连续致密且石墨化程度提高。因此,多糖生物质与APP具有较好地协效阻燃环氧树脂的作用。

Two kinds of biomass with polysaccharide structures,chitosan(Cs)and starch(St),were chosen as synergists to improve the flame retardancy of epoxy resin(EP)/ammonium polyphosphate(APP).The synergistic effects of polysaccharide biomass and APP on the flame retardancy of EP were studied.The flame retardancy was characterized by limiting oxygen index,vertical combustion,cone calorimetry,thermogravimetric analysis,scanning electron microscopy and Raman spectroscopy,etc.The results show that,compared with only adding the same amount of APP,the synergistic flame retardant system of polysaccharide biomass and APP has a significant flame retardant effect on EP.The synergistic flame retardancy is optimal when the mass fraction ratio of APP to chitosan or starch is 12∶2 or 13∶1.The limiting oxygen index of EP/APP is 26.7%,which reaches 28.2%for EP/APP/chitosan system and 28.4%for EP/APP/starch system.Combustion grades increases from HB grade to V-0 grade.At the same time,the peak of heat release rate and total heat release are significantly reduced.CO and CO_(2)emissions are significantly reduced.The amounts of residual chars increase significantly and the residual chars are continuous,dense and high graphited.Thus,polysaccharide biomass displays a good synergistic effect with APP on the flame retardancy of EP.