APP对PUI泡沫泡孔结构及燃烧后炭层结构的影响

以聚磷酸铵(Ammonium Phosphate,APP)为阻燃剂,采用PI(poly-imide)预聚法制备了APP阻燃聚氨酯-酰亚胺泡沫塑料。利用偏光显微镜、扫描电子显微镜(SEM)、热重(TGA)观察分析了APP对泡沫泡孔结构、热稳定性和炭层形貌的影响。重点探讨了泡孔结构的变化对燃烧后的炭层形貌的影响,并模拟了炭层的形成过程。结果表明,随着APP添加量的增加,泡孔直径由540.39μm下降到277.83μm,泡沫密度增加;APP的加入使泡沫的残炭率增加了30%;泡孔的棱边和顶点分别炭化膨胀为炭层上的棒状炭层和球状炭层,而泡孔薄膜破裂成孔洞;并且随着APP添加量的增加,棒状炭层和球状炭层尺寸增加,孔洞变小。

Effects of Ammonium Phosphate on Structure of Cell and Carb on Layer after Burned of Polyurethane-imide Foams

Using ammonium phosphate as flame retardant,polyurethane-imide foams were synthesized via PI pre-polymer method.The effect of APP on the cell structure, thermal stability and carbon layer morphology were analyzed by polarizing microscope,SEM and TGA.The effect of cell structure change on carbon layer morphology was focused and discussed and the formation process of carbon layer was simulated.The results show that cell diameter drops sharply from 690.25μm to 277.83μm, the foam density increases with the increasing addition of APP;the addition of APP makes char yield increased by 30%;the cell wall and peak respectively expand into rod-like and spherical carbon layer, but the cell films burn into holes.Furthermore, the sizes of rod-like and spherical carbon layer increase, but the holes decrease with the increasing addition of APP.