钼酸铵对EVA/NBR复合材料燃烧性能及热稳定性的影响

采用共混法在乙稀醋酸乙烯共聚物/丁腈橡胶（EVA/NBR）复合材料中加入钼酸铵（AHM），通过烟密度测试、燃烧行为测试及热重分析研究了钼酸铵对复合体系的燃烧性能、抑烟性及热稳定性的影响。结果表明，添加1.0份（质量份，下同）AHM的复合材料的最大烟密度值降低到59.5 %，且烟密度等级仅为34.7，极限氧指数可达到33.3 %，UL 94垂直燃烧等级达到V-0级别，且燃烧时最大热释放速率从302 kW/m2降低到241 kW/m2；加入AHM后，复合材料的热稳定性提高；加入AHM后，烟密度实验后的残炭表面形貌更加致密。

Effects of Ammonium Molybdate on Flame Retardancy,Smoke Suppression and Thermal Stability of EVA/NBR Composites

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.