Study On Antimony Trioxide Collaborate With Decabromodiphenylethane Flame Retarding HDPE

High-density polyethylene (HDPE) is one of the five most important general plastics, due to its excellent comprehensive performance, it has been widely used in many fields of production and life. However, the limiting oxygen index of HDPE is low (only about 19) and HDPE is extremely flammable. When HDPE burns, it burns fast and produces a large number of dripping-melt then lead to a serious security hidden danger. In this paper, DBDPE and Sb2O3 are selected as antimony-halogen-flame-retardant to improve the flame retardant performance of HDPE. The flame-retardant synergism of DBDPE and Sb2O3 in HDPE were studied.Then mix the antimony-halogen-flame retardant with MTH, ZB, LDHs, ATH and OMMT etc. to do flame retardant modification for HDPE, and the flame retardant properties, mechanical properties and thermal stability of HDPE composites were characterized by means of the limiting oxygen index, horizontal and vertical combustion grade, tensile and bending properties, microcomputer differential thermal balance tests. The results are concluded as follows:When DBDPE/Sb2O3=3/1, as the content of halogen flame retardant antimony growth, the limiting oxygen index of composites increases. When Sb2O3 content is 6phr, the LOI value of materials can reach to 28.1%, but its mechanical properties declines. Make the dosage of DBDPE and Sb2O3 the same, with the increase of the Sb2O3 particle size, the flame retardant performance of HDPE composite decrease. The LOI value of HDPE composite can reach to 28.2 when Sb2O3 particle size is 0.5?m and its horizontal and vertical combustion grade reach to HB level and V-0 level respectively, meanwhile, the mechanical properties and thermal stability maintain well. With the growth of DBDPE/Sb2O3 mass ratio, the trend of flame retardant properties and thermal stability of HDPE composite firstly presents increases, then decreases, and its mechanical properties decline slowly. When DBDPE/Sb2O3 mass ratio is 3:1, the flame retardant properties, mechanical properties and thermal stability of the composites all are well, so the optimum ratio of DBDPE/Sb2O3 is 3:1.As DBDPE/Mg(OH)2 ratio decreases, the horizontal and vertical combustion level of material is the highest HB level and V-0 level, and its limiting oxygen index firstly increases, then decreases. DBDPE/Mg(OH)2=1:1 is determined as the optimum ratio. When ZB or LDHs was separately added, the oxygen index of materials reduced. The carbon residue of materials increases when they burns, and its thermal stability was improved; Both ZB and LDHs add to materials and the thermal weight loss rate of flame retardant system is low to 78.23% when ZB/LDHs= 3:1. After adding OMMT, the vertical combustion level of material increases from V-1 level to V-0 level, and its horizontal combustion level is the highest HB level. With the increase of OMMT1 dosage, the oxygen index increases from 27.2 to 27.8, and then reduced to 27.5, as the OMMT4 dosage increases, the oxygen index is continuously increasing, increased from 27.7 to 28.0, and its thermal stability was improved, the burning dripping-melt problems of material are effectively resolved, and OMMT are determined as the optimum content of 6 phr.