聚芳酰胺多孔膜的制备及其介电性能研究

以间苯二胺和间苯二甲酰氯为单体，2-甲基吡啶为缚酸剂，N，N-二甲基乙酰胺为溶剂，用低温溶液缩聚法合成了间位聚芳酰胺（PMIA）；然后以乙醇为非溶剂，用非溶剂致相分离法成功制备了不同孔结构的聚芳酰胺多孔膜.采用核磁及红外等手段对所合成聚芳酰胺的结构进行了表征，考察了聚芳酰胺溶液浓度对多孔膜孔结构及介电性能的影响.结果表明:当聚芳酰胺的浓度为21%，17%和15%时，都可以得到孔结构规整的多孔膜，它们在1 MHz频率的介电常数分别为2.31，2.07和1.89，与聚芳酰胺标准膜的介电常数6.22相比分别降低了63%，67%和70%. 

Preparation of Porous Aromatic Polyamide Membranes and Their Dielectric Properties

Poly m-phenylene isophth alamide(PMIA) was synthesized using m-phenylenediamine and isophthaloyl chloride as monomers, 2-methylpyridine as acid binding agent by the low-temperature solution polymerization in N, N-dimethylacetamide (DMAc). Porous PMIA membranes with different pore structures were then prepared by non-solvent induced phase separation, and ethanol was used as non-solvent coagulation bath. The structures of PMIA were characterized by Fourier transform infrared and ¹H-nuclear magnetic resonance. The influence of polymer concentration on the pore structure and dielectric constant of the porous PMIA membrane was studied. Results show that when the concentration of PMIA is 21%, 17% and 15%, porous membranes with regular pore morphologies can all be obtained. Their dielectric constants are 2.31,2.07 and 1.89 respectively at 1 MHz, decreased by 63%, 67% and 70% than 6.22 of PMIA standard membrane.