Synergistic effects of modified hydrotalcite on improving the fire resistance of ethylene vinyl acetate containing intumescent flame retardants-Sheng Zhang

Synergistic Effects of Modified Hydrotalcite onImproving the Fire Resistance of Ethylene VinylAcetat e Containing Intumescent Flame RetardantsSheng Zhang, Wufei Tang, Jun Sun, Yu Jiang, Xiangxing Bu, Xiaoyu GuKey Laboratory of Carbon Fiber and Function al Polymers, Ministry of Education,Beijing University of Chemical Technology, Beijing 100029, ChinaThe NH2SO213intercalated MgAl-LDH (SA-LDH) wasprepared and then introduced into ethylene vinyl ace-tate (EVA) in association with intumescent flameretardants (IFR) in order to improve the flame retard-ancy of the composite. The structure and thermal sta-bility of SA-LDH was characterized by Fouriertransform infrared, X-ray diffraction, transmission elec-tron microscopy, and thermogravimetry analysis. Theflame retardancy of EVA composite was evaluated bylimiting oxygen index (LOI), vertical burning UL-94, andcone calorimeter tests. The presence of only 1 wt%SA-LDH could increase the LOI of EVA/IFR compositefrom 24.8 to 26.9, and significantly reduced the peakHRR value. The morphology of char after combustionwas observed by scanning electron microscope, and itrevealed that the presence of SA-LDH was beneficialto form compact char structure. It was proposed thatthere existed synergism between SA-LDH and IFR inimproving the fire performance of EVA composite.POLYM. COMPOS

request for full text