通过氨基硅烷偶联剂（GAS）对二氧化硅（SiO₂）纳米颗粒进行改性，使用改性的SiO₂纳米颗粒增强聚氯乙烯（PVC）纳米复合材料的介电性能和力学性能，且研究改性SiO₂纳米颗粒掺量对其性能的影响。结果表明：随着改性SiO₂添加量的增加，PVC复合材料的相对介电常数呈现先降低后升高的趋势，且在添加量为1.5%时达到最低，为2.97，相较于纯PVC材料的相对介电常数降低了26.12%；而PVC复合材料在直流和支流电场下的击穿强度均呈现先上升后下降的趋势，其中均在添加量为1.0%时达到最高，在直流和支流电场条件下的击穿强度分别为70.21、60.12 kV/mm，且较纯PVC材料的击穿强度分别增加了20.48%、30.36%。此外，在1.0%添加量下，PVC复合材料的拉伸强度、弯曲强度及断裂伸长率分别为49.33 MPa、92.67 MPa和187.34%。

Silicon dioxide(SiO₂) nanoparticles were modified using aminosilane coupling agents (GAS), and the modified SiO₂ nanoparticles were used to enhance the dielectric and mechanical properties of PVC nanocomposites. The effects of the addition of modified SiO₂ nanoparticles on them were studied. The results showed that with the increase of modified SiO₂, the relative dielectric constant of PVC composites shows a trend of first decreasing and then increasing, and reaches the lowest value of 2.97 at 1.5% addition, which is 26.12% lower than that of pure PVC materials. The breakdown strength of PVC composites shows a trend of first increasing and then decreasing under both direct current and branch electric fields, with the highest breakdown strength reached at a addition of 1.0%. The breakdown strength under direct current and branch electric field conditions is 70.21, 60.12 kV/mm, respectively, and the breakdown strength of pure PVC materials has increased by 20.48% and 30.36%, respectively. In addition, at a addtion of 1.0%, the tensile strength, flexural strength and elongation at break of PVC composites are 49.33 MPa, 92.67 MPa and 187.34%, respectively.