聚吡咯-钴锌铁氧体复合材料的制备及性能

Preparation and Properties of Polypyrrole-Co_(0.5)Zn_(0.5)Fe_2O_4 Composites

用聚丙烯酰胺凝胶法制备纳米Co0.5Zn0.5Fe2O4铁氧体,再用原位聚合法制备聚吡咯-钴锌铁氧体(PPy-Co0.5Zn0.5Fe2O4)复合材料。使用X射线衍射仪(XRD)和扫描电子显微镜(SEM)表征了复合材料的结构和形貌,用振动样品磁强计(VSM)和矢量网络分析仪测试了复合材料的磁性能和介电性能。结果表明:样品为纯PPy和PPy-Co0.5Zn0.5Fe2O4,平均粒径分别约为200 nm和180 nm;Co0.5Zn0.5Fe2O4的磁化强度(Ms)和剩余磁化强度(Mr)分别为65.95 emu/g和15.44 emu/g,均大于PPyCo0.5Zn0.5Fe2O4,但矫顽力(Hc)为153.51 Oe,小于PPy-Co0.5Zn0.5Fe2O4;PPy的介电损耗(tanε=ε''/ε')大于PPy-Co0.5Zn0.5Fe2O4,反射损耗小于PPy-Co0.5Zn0.5Fe2O4,这是Co0.5Zn0.5Fe2O4的引入所致;在频率为15.2 GHz处,PPy-Co0.5Zn0.5Fe2O4复合材料的反射损耗达到最大值-16.4 dB,频带宽为2.5 GHz。

Nanocrystallined cobalt zinc ferrite was prepared by polyacrylamide gel process, and then the polypyrrole （PPy）-cobalt zinc ferrite composites were synthesized by in-situ chemical polymerization. The microstructure and morphology of the composites were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The magnetic and microwave dielectric properties of the composites were measured by vibrating sample magnetometer （VSM） and vector network analyzer of E5071C. The results show that the products are composites consisted of pure PPy and PPy-Co0.5Zn0.5Fe2O4, and the average particle sizes of PPy and PPy-Co0.5Zn0.5Fe2O4 are about 200 nm and 180 nm, respectively. The saturation magnetization （Ms） and remanent magnetization （Mr） of the Co0.5Zn0.5Fe2O4 are 65.95 emu/g and 15.44 emu/g, respectively, and they are greater than that of PPy-Co0.5Zn0.5Fe2O4, but the coercive force （Ho） of the Co0.5Zn0.5Fe2O4 is smaller than that of PPy-Co0.5Zn0.5Fe2O4. Owing to the introduction of Co0.5Zn0.5Fe2O4 ferrites into the PPy matrix, the dielectric loss （tanδ=ε″/ε′） of the PPy is greater than that of the PPy-Co0.5Zn0.5Fe2O4, but the reflection loss of the PPy is smaller than that of the PPy-Co0.5Zn0.5Fe2O4. The maximum reflection loss of the PPy -Co0.5Zn0.5Fe2O4 composite is about-16.4 dB at 15.2 GHz with a bandwidth of 2.5 GHz.