硼酸锌对氮磷协效阻燃玻纤增强尼龙66性能的影响

为提高三聚氰胺聚磷酸盐(MPP)和二乙基次膦酸盐(OP)协效阻燃玻纤(GF)增强尼龙66(PA66)的综合性能,引入少量的无机阻燃剂硼酸锌(ZB)作为协效剂,系统研究了不同添加量的ZB对阻燃材料的阻燃性能、热稳定性、力学性能和白度的影响。结果表明,当MPP和OP的总添加量为15%,复配0.5%的ZB时,阻燃GF增强PA66的垂直燃烧阻燃等级达到UL94 V–0级,且热释放总量由MPP/OP体系的15.4 k J/g降为13.7 k J/g;ZB的引入促进了连续、致密炭层的形成,增强了凝聚相阻燃;ZB增强了阻燃材料的热稳定性,ZB复配量为1.0%的阻燃材料的初始降解温度提高到了301℃,有效避免了加工过程中的降解;当ZB添加量为1.0%时,阻燃材料的拉伸强度和缺口冲击强度分别为100.9 MPa和4.22 k J/m~2,均优于未添加阻燃剂的纯GF增强PA66;同时,样品的白度得到了明显提升,有利于阻燃GF增强PA66的工业化应用。

Influences of ZB on Properties of Nitrogen-Phosphorus Synergistic Flame Retardant GF Reinforced PA66

Aiming at improving the comprehensive properties of the melamine polyphosphate (MPP) and diethyl phosphinate (OP) flame retardant glass fiber (GF) reinforced polyamide 66 (PA66),the inorganic flame-retardant zinc borate (ZB) was used as the synergistic agent. The influences of ZB content on the properties of flame retardant GF reinforced PA66,including flame retardancy, thermal stability,mechanical properties and whiteness,were systematically investigated. The results indicate that when the additive amount of ZB is 0.5%,the additive amount of MPP/OP is 15%,flame retardant GF reinforced PA66 can reach UL94 V–0 rating, and the heat release value decreases from 15.4 kJ/g (value for MPP/OP flame retardant GF reinforced PA66 system) to 13.7 kJ/g. The introduction of ZB is favor to promoting the formation of continuous and compact char layer in condense phase. Thermal stabil-ity of the flame retardant GF reinforced PA66 is significantly enhanced due to the addition of ZB,thus avoiding the slight degrada-tion of the flame retardant GF reinforced PA66 during processing. With increasing the ZB content to 1.0%,the tensile strength and notched impact strength of the flame retardant GF reinforced PA66 are 100.9 MPa and 4.22 kJ/m2,respectively,better than that of pure sample (GF reinforced PA66). In addition,introducing 1.0% ZB dramatically improves the whiteness of flame retardant GF reinforced PA66 which is helpful to promote its industrial applications.