不同微结构SiCNO陶瓷的制备及介电特性研究∗

摘要

以双亲性嵌段共聚物F127(PEO106-PPO70-PEO106)为模板剂，聚乙烯基硅氮烷(PVSZ)为前驱体，采用软模板法和无压烧结工艺制备出不同微结构SiCNO 陶瓷.利用扫描电镜、电子探针、X射线衍射仪、动态光散射、热重分析和阻抗分析仪等手段表征 SiCNO 陶瓷，并分析了不同形貌结构对陶瓷介电损耗特性的影响.结果表明，通过精确控制蒸发温度可制备出棒状、十字架状、球形和卵形结构SiCNO 陶瓷；SiCNO 陶瓷介电损耗与形貌结构密切相关，介电损耗值随着蒸发温度升高呈先增大后降低的趋势，当陶瓷微观结构为十字架结构时，介电损耗达到最高值为0．24；当陶瓷微观结构为卵形结构时，介电损耗最低值为0．03.%The different microstructured SiCNO ceramics were prepared by using amphiphilic block copolymer F127 (PEO106-PPO70-PEO106 )as template agent and polyvinysilazane (PVSZ)as the precursors.The morpholo-gy and structure properties of the SiCNO ceramics were characterized by scanning electron microscopy,electron probe,X-ray diffraction,dynamic light scattering,thermogravimetric analysis and impedance analyzer.The re-sults show that the SiCNO ceramics with rod like,cross shaped,spherical and oval structures were prepared by controlling the evaporation temperature.Furthermore,the influence of different microstructured SiCNO ceram-ic dielectric loss characteristics were studied,the dielectric loss of the lowest and highest values were 0.03 and 0.24,corresponding to the oval structure and the cross structure.