A novel zinc chelate complex containing both phosphorus and nitrogen for improving the flame retardancy of low density polyethylene
writer：Cao ZH, Zhang Y, Song PA, Cai YZ, Guo Q, Fang ZP, Peng M*
keywords：zinc chelate, polyethylene, flame retardant
source：期刊
specific source：J. Anal. Appl. Pyrol. 2011.11, 92(2): 339-346
Issue time：2011年
A novel metal chelate complex, Zn-TEPAPM, was synthesized through reacting Zn(OAc)2 with the ligand of tetraethyl (1,2-phenylenebis(azanediyl)) bis (2-hydroxylphenylmethylene) diphosphonate (TEPAPM) and characterized by FT-IR, 1H-NMR, and 31P NMR spectra. The flame retardancy and thermal behavior of the intumescent flame retardant low density polyethylene (LDPE) containing Zn-TEPAPM were investigated by limiting oxygen index (LOI), thermal gravimetric analysis (TGA) and cone test. The results showed that Zn-TEPAPM has better effects on the thermal stability, the char formation and smoke inhibition ability for LDPE because it can act both as the inhibitor of radicals and as the promoter of carbonization. The TG curves shows that addition of 1 wt% Zn-TEPAPM in LDPE could improve the onset and maximum degradation temperature of LDPE from 429°C and 469°C to 442°C and 488°C, respectively. A reduced of 32% for the peak heat release rate (PHRR) was obtained in cone test of addition 1wt% Zn-TEPAPM in LDPE. Moreover, Zn-TEPAPM can be used as an effective synergist of ammonium polyphosphate (APP). When 1wt% of Zn-TEPAPM was loaded in LDPE/APP, the PHRR reduced by 32% more compared with that of LDPE/APP without Zn-TEPAPM, and the char layer became more compact and intact.