What is the flame retardant effect of DDMDP on polyethylene?
The total number of DMDBPs is 2,3-dimethyl-2,3-diphenylbutane. Because of its structural specificity, the CC bonds between the corresponding quaternary carbon atoms are not stable and are easily dissociated and formed. Free radicals. In foreign countries, biscumyl groups and their derivatives are attributed to free radical initiators with unstable C-C bonds, which are mainly used as flame-retardant synergists and cross-linked copolymerization catalysts. Compared with common radical initiators such as peroxides and azo compounds, they are highly stable and safe to use. As a flame-retardant synergist, a combination of dry and flame retardant synergists, on the one hand, forms a radical to transfer and combine halogen chains. On the other hand, when the outside temperature increases, halogen radicals are generated to achieve a flame retardant effect, as shown in the following figure. The effect of the addition amount of DMDPB on the tensile strength of the system is not significant, and the elongation at break of the system tends to decrease with the increase of the DMDBP addition, which may be due to the interface state of the system with the increase of the addition of DMDBP. Worse reasons. With the increase of the added amount of DMDBP, the flame retardant performance of the system is improved. When the added amount reaches 1.2 parts, the flame retardant performance can be achieved. Taking into account the tensile properties and flame retardancy, taking into account the cost factor, it can be determined that the appropriate amount of DMDBP in the system is 1-2 parts. DMDPB has a significant flame-retardant synergistic effect. In the LDPE/Sb2O3/DBDPO=100/5/3 system, the addition of 1 part of DMDBP can significantly increase the elongation at break, and at the same time greatly improve the flame retardancy, and the oxygen index reaches 29.