石墨烯/环氧树脂复合材料增韧机理研究

摘要

Light porous graphene aerogels were prepared by freeze drying the graphene oxide which was reducted with ethylenediamine.Graphene/epoxy resin composite materials were prepared with light porous graphene aer-ogels and thermosetting resin material in a thermostat by vacuum pouring.Mechanics performance test showed that the fracture toughness of graphene/epoxy resin composite material increased significantly compared with the pure resin material.When the content of graphene is within the range of 0~0.70 wt%,the toughness in-creased with the increase of concentration.When the content exceeded 0.70 wt%,the toughness decreased with the agglomeration of graphene.Therefore,the optimal content of graphene is 0.70 wt%.SEM fracture analysis showed that the addition of graphene made the energy required to generate new cracks and deformations can be significantly increased,which explained the influence mechanism of graphene and its content value on the toughness of graphene/epoxy resin composites.%用乙二胺将氧化石墨烯还原,经过冷冻干燥得到质轻的多孔石墨烯气凝胶,再用热固性树脂材料在恒温箱中真空浇筑浸渍石墨烯气凝胶,得到石墨烯/环氧树脂复合材料.力学性能测试表明,石墨烯/环氧树脂复合材料断裂韧性相比纯树脂材料显著提高,且石墨烯含量在0~0.70%(质量分数)范围内,韧性随含量升高而增加;含量超过0.70%(质量分数),韧性由于石墨烯的团聚作用而下降,因此可知石墨烯的最佳含量为0.70%(质量分数).SEM断面分析可知,石墨烯的加入使得材料裂纹的路径和断面在扩展过程中增加,导致新裂纹所需的表面能和塑性变形能显著增加,从而从微观上解释了石墨烯的存在及其含量值对石墨烯/环氧树脂复合材料韧性的影响机理.