无卤阻燃乙烯-醋酸乙烯酯共聚物泡沫复合材料的制备及性能表征

为使得乙烯-醋酸乙烯酯共聚物(EVA)泡沫复合材料具有阻燃功能,分别添加膨胀石墨-聚磷酸铵(EGAPP)和膨胀石墨-聚磷酸铵-热塑性淀粉(EG-APP-TPS)两种不同复配阻燃剂,通过熔融共混和硫化发泡制备了无卤阻燃EVA泡沫复合材料。采用极限氧指数(LOI)、垂直燃烧(UL-94)、热分析质谱联用(TG-MASS)及扫描电镜(SEM)测试等对EG-APP/EVA及EG-APP-TPS/EVA泡沫复合材料进行表征。结果表明:EG-APP复配阻燃剂添加量为30wt%、EG与APP质量比为1∶4时,EG-APP/EVA泡沫复合材料的LOI达28.1%,UL-94为V-1级;而当EG-APP-TPS复配阻燃剂添加量同为30wt%,EG、APP与TPS质量比为1∶4∶1时,EG-APP-TPS/EVA泡沫复合材料的LOI可达29.3%,UL-94为V-0级。TG-MASS和SEM分析表明:EG、APP和TPS在气相和固相中均具有显著的协同阻燃作用。

Preparation and property characterization of halogen-free fire retardant ethylene-vinyl acetate copolymer foam composites

In order to obtain retardant ethylene-vinyl acetate (EVA) foam composites, two different compounded fire retardant consisting of expandable graphite-ammonium polyphosphate (EG-APP) and expandable graphite-ammonium polyphosphate-thermoplastic starch (EG-APP-TPS) were added to prepare alogen-free fire retardant EVA foam composites by process of molten blending and sulfuration foam. The EG-APP/EVA and EG-APP-TPS/EVA foam composites were characterized by limit oxygen index (LOI), vertical combustion (UL-94), thermal analysis mass spectrometry (TG-MASS) and scanning electron microscopy (SEM) test. The results demonstrate that the LOI of EG-APP/EVA foam composite is 28.1% and the flame retardant grade reaches to UL-94 V-1 at 30wt% total loading of EG and APP with mass ratio of 1:4.However, at 30wt% total loading of EG, APP and TPS with mass ratio of 1:4:1, LOI 29.3% and UL-94 V-0 rating are obtained. The results from TG-MASS and SEM tests show a good synergistic effect of EG, APP and TPS in solid and gas phase.