Improving the flame-retardant efficiency of aluminum hydroxide with fullerene for high-density polyethylene
作者:Pan YQ, Han LG, Guo ZH, Fang ZP
关键字:composites; flame retardance; mechanical properties; thermogravimetric analysis (TGA)
论文来源:期刊
具体来源:Journal of Applied Polymer Science,2017, 134(9): 44551
发表时间:2017年
The influence of fullerene (C-60) on the flame retardancy and thermal
stability of high-density polyethylene (HDPE)/aluminum hydroxide (ATH)
composites was studied. After the addition of three portions of C-60 to
an HDPE-ATH (mass ratio=100:120) composite, a V-0 rating in the UL-94
vertical combustion test was achieved, and the limiting oxygen index
increased by about 2%. The results of cone testing also showed that the
addition of C-60 effectively extended the time to ignition and the time
to maximum heat-release rate while cutting down the peak heat-release
rate. Thus, fewer flame retardants were needed to achieve a satisfactory
flame retardance. Consequently, the adverse effects on the mechanical
properties because of the high level of flame-retardant loading was
reduced, as evidenced by the obvious enhancements in the tensile
strength, elongation at break, and flexural strength. Electron spin
resonance spectroscopy proved that C-60 was an efficient free-radical
scavenger toward HO center dot radicals. Thermogravimetric analysis
coupled to Fourier transform infrared spectroscopy demonstrated that in
both N-2 and air atmospheres, C-60 increased the onset temperature of
the matrix by about 10 degrees C because of its enormous capacity to
absorb free radicals evolved from the degradation of the matrix to form
crosslinked network, which was covered by aluminum oxide.