【摘要】 采用Stober法对高介电常数陶瓷填料钛酸钡（BT）进行改性，得到二氧化硅（SiO₂）包覆BT （BT@SiO₂）填料，并采用溶液浇铸法制备具有高介电储能性能的聚醚酰亚胺（PEI）/BT@SiO₂复合材料薄膜，研究了复合材料薄膜的表面结构、结晶行为、介电性能、储能性能等。X射线衍射（XRD）及透射电子显微镜结果表明，SiO₂成功包覆在BT粒子的表面，制备了具有“核-壳”结构的BT@SiO₂填料；扫描电子显微镜、XRD结果表明，BT@SiO₂填料在PEI基体中分散均匀，SiO₂层增强了填料的分散性；介电性能、储能性能测试结果表明，高介电常数BT@SiO₂填料的引入有效增强了PEI复合材料的介电常数，降低介电损耗。当BT@SiO₂填料的体积分数为0.2%时，PEI复合材料的特征击穿强度达到最大值468 MV/m，相对纯PEI提高了16%，在电场强度为400 MV/m的条件下，其放电能量密度为4.1 J/cm³，相对纯PEI提高了192%，充放电效率为72%。更多还原

【Abstract】 A ceramic filler with high dielectric constant—barium titanate （BT） was firstly coated with silicon dioxide （SiO₂） via Stober method for preparing BT@SiO_{2 filler}，and then polyetherimide （PEI）/BT@SiO₂ composite film with high dielectric and energy storage properties was prepared by solution casting method.The surface structure，crystallization behavior，dielectric properties and energy storage properties of the composite film were investigated.The X-ray diffraction （XRD） and transmission electron microscope results show that SiO₂ is successfully coated on the surface of BT particles，and BT@SiO₂ filler with a "core-shell" structure is prepared.Scanning electron microscope （SEM） and XRD results show that BT@SiO₂ filler is uniformly dispersed in the PEI matrix，and SiO₂ layer enhances the dispersion of the filler.The test results of dielectric properties and energy storage performance show that the introduction of high dielectric constant BT@SiO₂ fillers effectively enhances the dielectric constant of PEI composites and reduces dielectric loss.When the volume fraction of BT@SiO₂ filler is 0.2%，the characteristic breakdown strength of PEI composite reaches the maximum of 468 MV/m，which is 16% higher than that of pure PEI，under the condition of 400 MV/m，the discharge energy density is 4.1 J/cm³，which is 192% higher than that of pure PEI，and the charge-discharge efficiency is 72%.更多还原