杂化聚酰亚胺薄膜无机相形貌和介电性能研究

采用溶胶-凝胶法制备纳米二氧化硅及氧化铝溶胶,将其掺入聚酰胺酸溶液中,制得聚酰亚胺/二氧化硅-氧化铝杂化薄膜,利用原子力显微镜对杂化薄膜的无机相微观形貌进行表征,用精密阻抗分析仪测试杂化膜介电性能.研究表明:掺入无机组分含量均为4%时,随着掺入二氧化硅所占比例的增大,无机纳米粒子的平均粒径增加,当其与氧化铝质量比为8:1时无机相呈网络状,与聚酰亚胺基体界面模糊;掺入无机组分对杂化薄膜的介电性能产生影响,介电常数ε和介电损耗tgδ随频率增加而减小,在相同频率下随掺入二氧化硅所占比例增大,介电常数ε和介电损耗tgδ增大.

Study on micro-morphology of inorganic phase and dielectric properties of polyimide hybrid films

In this paper,silica-alumina/polyimide hybrid films were prepared by sol-gel method.The micro-morphology of the inorganic phase of the films were characterized by Atomic Force Microscope(AFM).The dielectric properties of hybrid films were measured by Agilent-4294 precision impedance analyzer.The results indicate that average particle diameter increased with augmentation of proportion of silica to alumina.When the proportion of silica to alumina in the film was 8 to 1,inorganic phase took on network shape.However,the interphase between inorganic phase and polyimide was illegible.Incorporating inorganic particles into polymide had great effect on dielectric properties.Dielectric constant and dielectric loss angle diminished when the frequency increased.When the content of SiO_2 increased dielectric constant and dielectric loss angle increased at the same frequency.