不同用水量对聚酰亚胺泡沫结构与性能的影响

Effect of Different Water Content on Structure and Properties of Polyimide Foam

以水作为发泡剂,利用水在反应过程中产生的无机低分子物CO_2进行发泡,制备了一种聚酰亚胺(PI)泡沫材料。研究了不同用水量对PI泡沫结构和性能的影响规律。通过红外光谱(FTIR)对PI泡沫的分子结构进行表征,通过扫描电子显微镜(SEM)对泡孔结构、大小及其分布规律进行观察,通过热机械分析仪(DMA)对PI泡沫的损耗因子(tanδ)与温度(T)的关系进行测试,通过热失重分析仪(TGA)对热稳定性进行表征。结果表明:在一定的用水量范围内,用水量对PI泡沫的分子结构和热稳定性均没有明显的影响,对PI泡沫的泡孔结构、大小及其分布影响较大。泡沫的泡孔大小随着用水量的增加而逐渐变小,泡孔结构及其分布更加均匀。PI泡沫的热分解温度为300℃左右,具有较好的耐热性能。

A polyimide（PI） foam was prepared by using water as blowing agent, which can produce CO2 during the reaction process. The effect of different water contents on the structure and properties of the PI foam was studied. The molecular structure of the PI foam was characterized by Fourier transform infrared spectroscopy（FTIR）. The cell structure, size and distribution were observed by scanning electron microscope（SEM）. The relationship between loss factor（tanδ） of the PI foam and temperature（T） was tested by dynamic mechanical analysis（DMA）, and the thermal stability was characterized by thermal gravimetric analysis（TGA）. The results show that of the water content has no significant effect on the molecular structure and thermal stability of the PI foam in a certain range, while it has great influence on the cell structure, size and distribution of the PI foam. With the increase of water content, the cell size of PI foam increases, and the cell structure and distribution are more uniform. The thermal decomposition temperature of the PI foam is 300 ℃, so it has good thermal stability.