滑石粉和间苯二酚双(二苯基磷酸酯)协效阻燃PC/ABS合金的研究

Study on Synergistic Effect of Talcum Powder and Resorcinol Bis(Diphenyl Phosphate)on the Flame-retardant Properties of PC/ABS Alloy

用γ-氨丙基三乙氧基硅烷表面处理的滑石粉(Talc)与间苯二酚双(二苯基磷酸酯)(RDP)复合阻燃质量比为7∶3的聚碳酸酯(PC)/(丙烯腈-丁二烯-苯乙烯)共聚物(ABS)合金,探讨了两者用量对PC/ABS阻燃性能和耐热性能的影响。研究表明,Talc与RDP有一定的协同阻燃作用,添加13.0 wt%Talc和7.0 wt%RDP后,PC/ABS可通过UL-94 V-0级,极限氧指数(LOI)为31.8%,热变形温度比同样阻燃等级、单独添加16.0 wt%RDP的PC/ABS(PC/ABS/R-16)高10℃以上。相比于单独用RDP阻燃,滑石粉与RDP复合后的PC/ABS(PC/ABS/R-7/T-13)热重分析图上残炭率从12.8%提高至24.0%,拉曼图谱表示热重分析的炭层的石墨化程度更高;扫描电镜图显示垂直燃烧后残炭的内层更致密,表明滑石粉的加入主要促进了RDP在凝聚相的阻燃作用,有助于体系生成更连续而致密的炭层。

A kind of flame retardant polycarbonate(PC)/acrylonitrile-butadiene-styrene copolymer(ABS)alloy with a quality ratio of 7∶3 was prepared withtalcum powder(Talc)treated by γ-aminopropyl triethoxysilane and resorcinol bis(diphenyl phosphate)(RDP)as flame retardants.The influence of the amounts of flame retardants on the thermal and flame-retardant properties of PC/ABS was discussed.Synergistic effect of modified talc and RDP on the flame-retardant properties of PC/ABS was found.With the addition of 13.0 wt%Talc and 7.0 wt%RDP,PC/ABS can pass UL-94 V-0 rating and achieve the limit oxygen index(LOI)of 31.8%.The heatdistortion temperature is 10℃higher than that of PC/ABS with 16.0 wt%RDP(PC/ABS/R-16)which can achieve UL-94 V-0 rating.Thermogravimetric analysis indicated that the char residue of this PC/ABS alloy increased from 12.8%to 24.0%after using talc powder and RDP as flame retardant(PC/ABS/R-7/T-13),compared with PC/ABS/R-16.Raman spectrum suggested that the degree of graphitization of the char was higher than that of PC/ABS/R-16.Moreover,scanning electron microscopeimages showed that the inner surface of the char of PC/ABS/R-7/T-13was more compact than that of PC/ABS/R-16.The above results demonstrated that the addition of talc mainly enhanced fire-retardant effect of RDP in the condensed phase,and helped the alloy to form a continuous and compactchar layer.