石墨烯制备方法及粒径对复合材料热导率的影响

The Graphene Preparation Methods and the Size Effect on the Thermal Conductivity of Composites

石墨烯是由碳原子构成的单原子厚度的二维层状材料,具有许多优异的性能,是当前国内外研究热点之一,受到物理、化学、材料、电子、能源、生物和信息技术等领域的广泛关注。石墨烯是目前所测得导热系数最高的材料,在强化传热领域具有潜在的应用价值。较为系统地研究了石墨烯的制备方法及石墨的粒径对环氧树脂复合材料热导率的影响。实验发现,所采用的三种插层剂(硫酸、十四烷基胺及FeCl3)中,添加量较少时(如体积分数为1%),十四烷基胺插层法最为有效。而添加量较高时,硫酸插层制备的石墨烯纳米片效果最佳。制备石墨烯纳米片所采用的石墨粒径较大时,石墨烯/环氧树脂(Epoxy)复合材料的热导率越高。通过优化石墨烯的制备方法,石墨烯纳米片在体积分数为3.9%时,其热导率可达0.94 W·m^(-1)·K^(-1)),比基体材料提高了2.6倍。

Graphene,a monolayer of carbon atoms with many unique properties,has gained much attention from various areas,such as the physics,chemistry,material,electron,energy,biology and information technique fields.The thermal conductivity of graphene is the highest among the existing materials,and it has a great potential applications in the field of heat transfer enhancement.In this paper,a systematic study of the effects of preparation method and raw particle size on thermal conductivity of epoxy composites containing graphene nanoplatelets（GNPs） is done.It is found that when the volume fraction of GNPs in epoxy composition is low（0=0.01）,the method using tetradecyl amine as intercalation agents is the best among the selected three intercalation agents.But when the volume fraction becomes large,GNPs prepared using sulfuric acid is the best.The size of raw material graphite has great influence on the composite thermal conductivity.The larger size for graphite,the higher thermal conductivity for graphene/epoxy resin（Epoxy） composite.By optimizing the preparation methods of GNPs,the thermal conductivity of composite can reach 0.94W·m-1·K-1,enhanced by 2.6 times than the matrix material when the volume fraction of GNPs is3.9%.