作者：LC Tang*, YJ Wan, D Yan, YB Pei, L Zhao, YB Li, LB Wu*, JX Jiang, GQ Lai
关键字：Graphene, Dispersion, Epoxy, Mechanical properties
论文来源：期刊
具体来源：Carbon
发表时间：2013年
The effect of dispersion state of graphene on mechanical properties of graphene/epoxy composites was investigated. The graphene sheets were exfoliated from graphite oxide(GO) via thermal reduction (thermally reduced GO, RGO). Different dispersions of RGO sheets were prepared with and without ball mill mixing. It was found that the composites with highly dispersed RGO showed higher glass transition temperature (Tg) and strength than those with poorly dispersed RGO, although no significant differences in both the tensile and flexural moduli are caused by the different dispersion levels. In particular, theTg was increased by nearly 11C with the addition of 0.2 wt.% well dispersed RGO to epoxy. As expected, the highly dispersed RGO also produced one or two orders of magnitude
higher electrical conductivity than the corresponding poorly dispersed RGO. Furthermore, an improved quasi-static fracture toughness (KIC) was measured in the case of good dispersion. The poorly and highly dispersed RGO at 0.2 wt.% loading resulted in about 24% and 52% improvement in KIC of cured epoxy thermosets, respectively. RGO sheets were observed to bridge the micro-crack and debond/delaminate during fracture process due
to the poor filler/matrix and filler/filler interface, which should be the key elements of the toughening effect.