中文摘要：

以天然鳞片石墨为原料，通过Hummers法制备氧化石墨，微波热解剥离制备出少层数的石墨烯纳米片。以硅烷偶联剂KH－560为改性剂，超声共混制备石墨烯纳米片／环氧树脂复合材料。采用FT—IR和SEM分析样品的微观结构和形貌，测试其介电性能。结果表明，随着石墨烯纳米片添加量的增加，复合材料介电常数呈现先增大后减小的趋势，当石墨烯纳米片含量为0．3％（质量分数）时，介电常数达到最大；石墨烯纳米片对复合材料介电损耗的影响与之相反；偶联改性使复合材料的介电常数增大，介电损耗减小。

英文摘要：

Graphene nanosheets （GNSs） with few-layer graphene have been prepared from natural flake graphite by oxidation intercalation and microwave expansion. Then GNSs was modified by silane coupling agent KH- 560. GNSs/EP composites was finally prepared by the ultrasonic mixing method. The structure and morphology of the samples were characterized by FT-IR and SEM. The dielectric properties of the composite was tested by impedance analyzer. The results show that the permittivity increases with the rise of GNSs content to the maximum when GNSs content get to 0.3wt %, and then decreases. The effect of GNSs content on dielectric loss was the opposite. Modified GNSs/EP composite has a higher permittivity and lower dielectric loss compared with GNSs/EP composite.