【摘要】 以均苯四甲酸二酐和4,4′-二氨基二苯醚为原料合成聚酰亚胺前体聚酰胺酸溶液,通过溶液诱导相分离和热酰亚胺化法制备聚酰亚胺多孔膜。结果表明,用该方法得到的聚酰亚胺多孔膜具有较好的热稳定性。SEM分析显示,在不同的凝胶浴组成、凝胶浴温度和挥发时间等制膜条件下,可得到不同孔结构的多孔膜。与指状孔膜相比,海绵状孔多孔膜具有较低的介电常数。当凝胶浴组成DMAc/H2O为20/80、凝固浴温度为25℃、挥发时间为20min时,多孔膜断面几乎完全由海绵状孔组成,介电常数为1.45。更多还原

【Abstract】 To explore low dielectric polyimide,cellular polyimide films were prepared from pyromellitic dianhydride and 4,4′-diaminodiphenyl ether via a combined technique of solution induced phase separation and thermal imidization.These polyimide films displayed good thermal stability.SEM analyses showed that the obtained polyimide films had various cellular structures with the different conditions,such as the composition and temperature of coagulation bath,staying time,etc.The films with sponge-like cellular structures exhibited lower dielectric constants than those with finger-like structures.When the film was prepared in the conditions the coagulation bath of DMAc/H2O of 20/80,the temperature of 25℃ and the staying time of 20min,the film was full of sponge-like structure and its dielectric constant was low to 1.45.更多还原