在40 Hz～10 MHz频率范围测量了纳滤膜在8种电解质溶液中的介电谱,发现了两个随电解质浓度而变化的弛豫,建立了由膜内支撑层和分离层以及溶液相构筑的三相体系介电模型,并利用严格的数值解析法计算了体系中各组成相的电参数,聚焦于10<'3>Hz左右因膜内层间界面极化而引起的低频弛豫,考察了两层电参数与电解质种类和浓度的关系,计算得到膜内各层的介电性质,并获得了关于不同电解质在膜内支撑层和分离层中的分布的信息.%Dielectric measurements were carried out on thesystems composed of nanofiltration membrane and dilute solutions of eight electrolytes over the frequency range from 40 Hz to t0 MHz. Two relaxations were observed for each system. Three-phase dielectric model, which consist of the supporting layer and separation layer of membrane and solution phase, was established. The electrical parameters of each layer were obtained through strict mathematical calculation. This paper focused on low-frequency relaxation about 103 Hz caused by interracial polarization between the two layers. The variation of electrical parameters of the two layers with concentration and species of the electrolyte was discussed in detail. Further, dielectric properties of each layer were obtained and the distribution information of different electrolyte in supporting layer and separation layer of membrane were given.
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