新型双层包裹聚磷酸铵的设计及其在耐老化阻燃交联聚乙烯复合材料中的应用

Design of novel double-layer wrapped ammonium polyphosphate and its application in aging-resistant and flame retardant crosslinked polyethylene composites

研究采用双层包裹聚磷酸铵来提高交联聚乙烯(XLPE)复合材料的力学性能、耐老化性和阻燃性。将聚磷酸铵(APP)用二氧化硅包裹,然后用受阻苯酚抗氧化剂3-(3,5-二叔丁基-4羟基苯基)(AO)接枝,制备双层包裹阻燃剂(MCAPP)。由于MCAPP和XLPE基体具有良好的相容性,提高了XLPE/MCAPP/CFA(XLPE-4)的拉伸强度和断裂伸长率。在135℃老化14天后,XLPE-4复合材料的断裂伸长率保留率达到61.1%,显著高于XLPE-1(2.6%)。这说明MCAPP可以提高XLPE电缆复合材料的耐老化性能。与XLPE-1相比,XLPE-4的最大烟密度和峰值放热速率分别降低了54.9%和89.7%。因此,双层包裹的抗氧化策略为获得高性能的XLPE复合材料提供了一个很好的途径。

In this study,double-layer wrapped ammonium polyphosphate(APP)is designed to enhance the mechanical properties,resistance and flame retardancy of crosslinked polyethylene(XLPE)composites.APP was wrapped with silica and then grafted with hindered phenol antioxidant 3-(3,5-di-tert-butyl-4 hydroxyphenyl)(AO)to prepare double-layer wrapped flame retardants(MCAPP).Due to the excellent compatibility between the MCAPP and XLPE matrix,the tensile strength and elongation at break of XLPE/MCAPP/CFA(XLPE-4)were improved.Moreover,the retention rate of elongation at break for the XLPE-4 composite reached 61.1%,significantly higher than that of XLPE-1(2.6%)at 135℃after aging for 14 d.This demonstrates that MCAPP could improve the aging resistance of XLPE cable composites.Compared with XLPE-1,the maximum smoke density and the peak heat release rate were reduced by 54.9%and 89.7%,respectively.Thus,the double-layer wrapping antioxidant strategy provides an excellent approach to obtain high-performance XLPE composites.