Influence of ingredients on the properties of the flame retardant compound based on polyethylene

Abstract

In this paper, the effects of a flame retardant system combining ATH/MPP (aluminum hydroxide/melamine phosphate) and the other additives such as zinc stearate (ZnSt) on some properties of flame retardant PE compound based on LDPE were studied. The total flame retardant content was 35% by weight. Mechanical properties (tensile at break, elongation at break), thermal stability, and fire resistance were determined by the respective methods ASTM D638, thermogravimetric analysis (TGA), scanning electron microscope (SEM), and UL-94 test. The obtained results showed that using the combination of ATH/MPP has increased the fire resistance and thermal stability of the PE compound. The sample CT7 (15%ATH/20%MPP/2%ZnSt) achieved the best fire resistance. The mechanical properties increased slightly when increasing the content of MPP and reached the maximum for samples containing only MPP. The SEM micrographs showed that the addition of zinc stearate improved the dispersion of ATH and MPP in the PE matrix. The effect of flame retardant additives and zinc stearate on the melt index value of the PE compound was also surveyed.