摘要
采用微波辐射发泡的方法制备密胺泡沫材料,在密胺树脂发泡液中分别加入硼酸、淀粉、草酸、柠檬酸等改性剂,研究了改性剂种类和含量与泡沫形貌、表观密度、吸水率、压缩强度、热稳定性及阻燃性之间的关系。实验结果表明,当改性剂用量为10%时,硼酸改性密胺泡沫的半寿温度(T_(50%))最高,达到484℃;淀粉改性密胺泡沫的初始分解温度(T_(5%))最高,达到207℃;草酸改性密胺泡沫的表观密度最低,为78.13 kg/m~3,最大失重速率温度最高,达到411℃;柠檬酸改性密胺泡沫泡孔形貌最好,闭孔结构最多,吸水率最低,压缩强度最高,极限氧指数(LOI)最高。综合分析,10%柠檬酸改性密胺泡沫的综合性能最佳,其表观密度为108 kg/m~3,吸水率为21.33%,压缩强度达到258 kPa,残炭率为12.94%,LOI达到34.3%。
The melamine foam materials were prepared via microwave radiation. Modifiers such as boric acid, starch, oxalic acid and citric acid were added into the foaming liquid to adjust the performance of the melamine foam materials. The influences of the type and content of modifiers on morphology, apparent density, water absorption ratio, compressive strength, thermal stability and flame retardancy of melamine foam were studied. The results show that when the content of modifier is 10%, the melamine foam modified with boric acid exhibits the highest half-life temperature(T_(50%)) of 484 ℃. Moreover, the melamine foam modified with starch show the highest initial decomposition temperature(T_(5%)) of 207 ℃, and the melamine foam modified with oxalic acid exhibits the lowest apparent density of 78.13 kg/m~3 and highest mass loss rate temperature of 411 ℃. The melamine foam modified with citric acid exhibits the excellent morphology with the largest closed cell structure, lowest water absorption ratio, highest compressive strength and the highest limiting oxygen index. Overall, the melamine foam modified with 10% citric acid shows the best comprehensive performance with the apparent density of 108 kg/m~3, water absorption ratio of 21.33%, compressive strength of 258 kPa, residual carbon rate of 12.94% and limiting oxygen index of 34.3%.
引文
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