关键词: 乙烯-醋酸乙烯共聚物, 丁腈橡胶, 钼酸铵, 燃烧性, 抑烟性, 热稳定性

Abstract: Ammonium molybdate(AHM) was introduced into EVA/NBR composites as a flame retardant. Smoke density test, limiting oxygen index, UL-94 test, cone calorimeter, and thermal gravimetric analysis(TG) were used to characterize the smoke suppression, flammability, and thermal behavior of the EVA/NBR composites. The maximum smoke density was reduced to 59.5 % and smoke density rating was only 34.7. The results of fire tests showed that the sample containing 1.0 phr AHM had a limiting oxygen index value of 33.3 % with V-0 rating of UL 94 test, and the heat release rate was decreased from 302 to 241 kW/m2. TG result showed that the thermal stability was improved. The morphology of residue char after smoke density test was observed and analyzed by scanning electron microscope (SEM), and it was found that the surface of the composites containing AHM was more compact.

Key words: ethylene-vinyl-acetate copolymer, nitrile rubber, ammonium molybdate, flame retar-dant, smoke suppression, thermal stability