纳米银/环氧树脂复合材料的制备及其介电性能的研究

采用紫外辐照还原的方法制备了纳米银粒子，研究了保护剂的添加、辐照强度和溶液配比等因素对纳米银粒子尺寸的影响。TEM反映出银粒子分散均匀，其粒度约为20nm。将制备出的纳米银与环氧树脂混合固化形成纳米复合电介质，研究了这种复合材料的介电性能：室温下复合材料的体积电阻率和工频击穿场强随着纳米银粒子的加入有所提高，介质损耗略有降低，而介电常数变化不大。结果表明，纳米银粒子能够提高基体聚合物的介电性能。这一现象可用库仑阻塞机制解释。

Study on Preparation and Dielectric Properties of Nano-Ag/Epoxy Resin Composite

Silver (Ag) nano-particles were prepared through ultraviolet radiation reduction and then the influence of protecting agent, intensity of radiation and mixture ration on nano-Ag particle sizes was studied. TEM result shows that Ag particles were dispersed evenly in solution and the particle size was about 20 nm. Nano-dielectric of nano-Ag/epoxy resin composite was prepared by solidification successfully. The dielectric property of the composite is discussed. The result is that resistivity (ρv)and breakdown electric-field intensity (Eb) at room temperature are improved; the dielectric loss (tanδ) is reduced and the permittivity (εr) changes little. It can be seen that the dielectric property of polymer material is improved by adding nano-Ag particles. This phenomenon can be explained by Coulomb block effect.