水发泡剂对聚酰亚胺泡沫结构与性能的影响

Effect of Water Blowing Agent on Structures and Properties of Polyimide Foams

采用一步法制备了一种聚酰亚胺(PI)泡沫,研究了水含量对聚酰亚胺泡沫结构和性能的影响规律。采用红外光谱(FTIR)和扫描电镜(SEM)分别表征了聚酰亚胺泡沫的分子结构和泡孔结构;采用热机械分析(TMA)和热失重分析(TGA)分别测试了聚酰亚胺泡沫的玻璃化转变温度和热稳定性;采用双通道声学分析仪测试了聚酰亚胺泡沫的吸声性能。研究表明:在所研究的水含量范围内,用水含量对聚酰亚胺泡沫的分子结构、玻璃化转变温度和热失重性能几乎无影响;驻波管法测得PI泡沫的平均吸声系数最大为0.44;玻璃化转变温度为294.7～295.6℃,热失重5%时的温度大于377.5℃,800℃时的残余质量大于49.6%。

Polyimide foams were prepared by single-stage process condensation,and study the effect of water content on their structures and properties.The molecular structure and cell structure of polyimide foams were characterized by FTIR and SEM,respectively;the glass transition temperature and thermal stability of polyimide foams were characterized by TMA and TGA,respectively;sound absorption properties of polyimide foams was characterized by two channels acoustic analyzer.The results show that the water content has no effects on the molecular structure,the glass transition temperature and thermal gravimetric properties of polyimide foams in the study range of water content;the biggest average absorption coefficient of polyimide foams measured by using standing wave pipe method is 0.44;the glass transition temperature of polyimide foams is between 294.7℃and 295.6℃,and the temperatures at 5% weight loss is higher than 377.5℃,the residual weight ratio at 800℃ is higher than 49.6%.