改性纳米Fe_3O_4与低密度聚乙烯组成复合介质的介电谱分析

Dielectric Spectrum Analysis of Compound Dielectric with Nano Fe_3O_4 Modified and Low Density Polyethylene

纳米Fe3O4是典型的顺磁性材料,将其与低密度聚乙烯(low density polyethylene,LDPE)复合,会给LDPE基体的磁、电等性能带来影响。为研究纳米Fe3O4加入对LDPE介电性能的影响,采用共沉淀法制备纳米级Fe3O4,并用不同方法对其进行改性,制备了不同条件的纳米Fe3O4粒子。将此纳米Fe3O4按质量分数0.25%～1%分别以熔融共混法与LDPE复合制得Fe3O4与LDPE的复合材料。以宽频介电谱仪进行了该Fe3O4与LDPE复合材料介电谱的研究,试验结果表明:纳米Fe3O4的加入及磁化对LDPE的介电常数和介电损耗均有影响,且其大小与掺杂方法及纳米Fe3O4质量分数有关。

Nano Fe3O4 is a typical paramagnetic material,and its doping into low density polyethylene（LDPE） may affect the magnetic,dielectric and other properties of the LDPE matrix.To research the influence of doping nano Fe3O4 on the dielectric properties of LDPE,we prepared Fe3O4 ferrite nanoparticles used for preparation of polyethylene（PE） composite by the chemical co-precipitation method and modified by different methods,and prepared the nano Fe3O4 and LDPE composite materials with different mass fractions from 0.25% to 1% by melt blending.Moreover,we investigated the relationship of permittivity and dissipation factors dependence of frequency by broadband dielectric spectrometer.The conclusions can be drawn that doping Fe3O4 and magnetization will affect permittivity and dissipation factors,and the influential degree is related to the doping methods and quality percentage of Fe3O4 ferrite nanoparticles.