Synthesis of A Novel Cyclotriphosphazene and Its Enhancement of Anti-aging and Flame Retardancy of Polyolefin

A novel cyclotriphosphazene polymer (PDP) was synthesized by one-step method with hexachlorocyclotriphosphazene (HCCP) and 4,4 '-biphenol (DOD) as raw materials. The effects of different reaction time and molar ratio of reactants on PDP yield and molecular weight were investigated. The results showed that when the reaction time reached 60 min, the yield and the molecular weight of PDP was the highest. The yield of PDP decreased with the increase of the molar ratio of HCCP to DOD, when the ratio of HCCP to DOD was 3 : 3, the molecular weight of PDP reached the maximum. The characterization results of FTIR and XPS showed that the method can effectively prepared PDP. XRD result showed that the PDP was non-crystalline polymer. The synthesized PDP was applied to the polyolefin cable materials by electron beam radiation cross-linking method. The results of aging experiments showed that the limiting oxygen index (LOI) of the samples increased from 20% to 21.6% with the addition of 5phr PDP. As for the sample without PDP, the elongation at break was reduced to almost 0 in 12 h and tensile strength to 0 in 25 h. However, the elongation of the sample with 5phr PDP still kept 30% in 100 h, and the tensile strength kept 90% in 100 h. It shows that PDP has good flame retardancy and excellent anti-aging properties.