纳米二氧化硅改性环氧树脂复合材料的性能研究

利用硅烷偶联剂对纳米SiO2进行表面改性，进而通过共混法将改性后的纳米SiO2粒子分散到环氧树脂(Epoxy)中，制备了不同纳米SiO2含量的SiO2/EP复合材料.利用IR，SEM和TGA、阻抗分析仪等研究了SiO2添加量对复合材料微观结构、热稳定性和介电性能的影响.结果表明，随着纳米SiO2含量的增加，SiO2/EP复合材料的热稳定性逐渐升高，介电常数和损耗因数则呈先降低后增加趋势；当纳米SiO2含量为4%时，纳米颗粒在复合材料中分散均匀，复合材料的热稳定性好，介电性能最优(当测试频率为1 GHz，介电常数为2.86，介电损耗为0.023 53).分析了复合材料热稳定和介电性能变化的微观机理.
The blending method was used to prepare nano-SiO2/epoxy composites, where nano-SiO2 was premodified using silane coupling agent. The influences of nano-SiO2 content on the microstructure, thermal stability and dielectric properties of SiO2/EP composites were studied by using IR, SEM, TGA, impedance analyzer et al. The microscopic mechanism of thermal stability and dielectric property evolutions of the SiO2/EP composites were also discussed. with the increase of nano-SiO2 content, the thermal stability of SiO2/EP composites gradually increased, while the dielectric constant and dielectric loss factor of the composites decreased first and then increased. When the content of nano-SiO2 equaled 4%, the nanoparticles exhibited a uniform dispersion in composite, its dielectric constant was 2.86, and its corresponding dielectric loss was 0.023 53.