中文摘要：

氧化石墨烯（GO）具有优异的热、力学等性能，被广泛用于提高电子封装用聚合物复合材料的热性能。然而，由于缺乏GO多层装配水平对聚合物热性能影响的研究，在选择GO增强体时，其多层装配的适宜水平选择成为难题。研究了两种装配水平（GO-1，34nm；GO-2，7nm；片径相近）的GO对环氧树脂（EP）热性能的影响。结果表明，由于多层装配水平不同，Go～1表面较平滑，呈相对刚性片状；而GO-2表面折皱起伏，呈柔性薄纱状。相比纯EP，GO-1（3％）／EP复合材料热导率提高了248％，热膨胀系数降低了37％，半失重温度提高了6K；而GO-2（2％）／EP复合材料热导率提高了105％，热膨胀系数降低了24％，半失重温度提高了5K。研究表明，GO的多层装配水平影响了其表面官能团含量、在基体中剥离／分散状态以及界面结合强度等，导致了其对树脂热性能不同的影响。因此，适当提高GO多层装配水平有利于增强树脂热性能，这对于利用其他类似C,O具有层状结构的增强体改善聚合物热性能具有一定的参考意义。

英文摘要：

Graphene oxide （GO） is widely used to improve the thermal properties of polymer composites for electronic packaging because of its excellent thermal and mechanical properties. However, due to the lack of research on the effect of GO multilayer assembly level to the thermal properties of polymers, the selection of appropriate level of the muhilayer assembly level becomes a problem during the selection of GO reinforcement. The effects of two kinds of GO multilayer assembly levels （ GO- 1, 34 nm ; GO-2, 7 nm ; with the similar lateral size） on the thermal properties of epoxy were investigated. The results show that due to different muhilayer assembly levels, GO-1 has a relatively rigid lamellar morphology with smooth surface and GO-2 has a flexible gauzy morphology with wrinkled surface. Compared to pure epoxy, the thermal conductivity is increased by 248% , the thermal expansion coefficient is reduced by 37% and the half-weight- loss temperature increases by 6 K of GO-1 （3wt%）/epoxy composites. While, the thermal conductivity increases by 105%, the thermal expansion coefficient reduces by 24% and the half-weight-loss temperature increases by 5 K of GO-2 （2wt%）/epoxy composites. The results indicates that the multilayer assembly level of GO affects the surface functional groups contents, the exfoliation/dispersion state in the matrix, and the interracial bonding strength, which leads to different effects on the thermal properties of the resin. Therefore, the appropriate increasement of GO muhilayer assembly level is beneficial to enhance the thermal properties of the resin, which can be extended to various GO-like reinforcements with layered-structure for enhancing the thermal properties of the polymeric materials.