Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180-3590, USA.
ACS Nano. 2009 Dec 22;3(12):3884-90. doi: 10.1021/nn9010472.
In this study, the mechanical properties of epoxy nanocomposites with graphene platelets, single-walled carbon nanotubes, and multi-walled carbon nanotube additives were compared at a nanofiller weight fraction of 0.1 +/- 0.002%. The mechanical properties measured were the Young's modulus, ultimate tensile strength, fracture toughness, fracture energy, and the material's resistance to fatigue crack propagation. The results indicate that graphene platelets significantly out-perform carbon nanotube additives. The Young's modulus of the graphene nanocomposite was approximately 31% greater than the pristine epoxy as compared to approximately 3% increase for single-walled carbon nanotubes. The tensile strength of the baseline epoxy was enhanced by approximately 40% with graphene platelets compared to approximately 14% improvement for multi-walled carbon nanotubes. The mode I fracture toughness of the nanocomposite with graphene platelets showed approximately 53% increase over the epoxy compared to approximately 20% improvement for multi-walled carbon nanotubes. The fatigue resistance results also showed significantly different trends. While the fatigue suppression response of nanotube/epoxy composites degrades dramatically as the stress intensity factor amplitude is increased, the reverse effect is seen for graphene-based nanocomposites. The superiority of graphene platelets over carbon nanotubes in terms of mechanical properties enhancement may be related to their high specific surface area, enhanced nanofiller-matrix adhesion/interlocking arising from their wrinkled (rough) surface, as well as the two-dimensional (planar) geometry of graphene platelets.
在这项研究中，比较了在纳米填料重量分数为 0.1 +/- 0.002%的情况下，含有石墨烯片、单壁碳纳米管和多壁碳纳米管添加剂的环氧树脂纳米复合材料的机械性能。测量的机械性能包括杨氏模量、极限拉伸强度、断裂韧性、断裂能以及材料对疲劳裂纹扩展的抵抗力。结果表明，石墨烯片明显优于碳纳米管添加剂。与单壁碳纳米管约增加 3%相比，石墨烯纳米复合材料的杨氏模量约增加 31%。与多壁碳纳米管约提高 14%相比，基线环氧树脂的拉伸强度提高了约 40%。具有石墨烯片的纳米复合材料的 I 型断裂韧性与环氧树脂相比约提高了 53%，而多壁碳纳米管约提高了 20%。疲劳阻力结果也显示出明显不同的趋势。虽然随着应力强度因子幅度的增加，纳米管/环氧树脂复合材料的疲劳抑制响应显著恶化，但对于基于石墨烯的纳米复合材料则出现相反的效果。与碳纳米管相比，石墨烯片在增强机械性能方面的优越性可能与其高比表面积、其褶皱（粗糙）表面引起的增强纳米填料-基质粘附/互锁以及石墨烯片的二维（平面）几何形状有关。
