石墨烯对环氧树脂泡沫炭石墨化、电导率和力学性能的影响

Effect of Graphene on Graphitization,Electrical and Mechanical Properties of Epoxy Resin Carbon Foam

环氧树脂基泡沫炭是一种具有三维海绵状结构的新型炭材料,独特的网状泡孔结构使其具有高孔隙率、耐高温、耐腐蚀、导电/导热可调等性能,应用前景广阔。但是环氧树脂的石墨化困难,本工作以石墨烯为异质成核改性剂,用以提高环氧树脂泡沫炭的石墨化程度、电导率和力学性能。采用简单的发泡、炭化和石墨化工艺制备了石墨烯改性环氧树脂泡沫炭。石墨烯异质成核剂诱导了泡沫炭碳微晶生长,增加了碳晶格条纹长度,减少了碳晶体混乱。研究表明,不含或含质量分数0.05%石墨烯改性泡沫炭的晶面间距、晶粒堆垛高度、石墨化度分别为0.343nm、3.35nm、8.42%和0.342nm、10.22nm、23.2%。此外,石墨烯作为晶胞成核位点会影响泡沫炭的平均晶胞尺寸,随着石墨烯含量的增加,泡沫炭平均晶胞尺寸先减小后增大。同时,石墨烯改性增大了泡沫炭的有序结构,提高了其导电性,当石墨烯的质量分数为0.05%时,泡沫炭电导率为53.8 S·m^(–1)。相对于纯泡沫炭(压缩应变为0.0096%),质量分数0.01%、0.02%、0.05%和0.10%的石墨烯改性泡沫炭压缩应变增加至0.208%、0.228%、0.187%和0.1146%。本研究为碳纳米材料/泡沫炭制备、碳结构和性能调控提供了新的研究方法。

Epoxy resin(EP CF)carbon foam is a new carbon material with a three-dimensional sponge-like structure.The EP CF has high porosity,high temperature resistance,corrosion resistance,and adjustable electrical/thermal conductivity,which possesses broad application prospects.However,epoxy resin is difficult to graphitize.Therefore,graphene was used as a heterogeneous nucleation modifier to improve the graphitization degree,electrical conductivity and mechanical properties of EP CF.Graphene modified EP CF was prepared by a simple process of foaming,carbonizing,and graphitizing.Graphene as heterogeneous nucleation agent induce the carbon crystallite growth in EP CF,which increases the lattice fringe length and reduces carbon crystal tangled.The results show that the interplanar spacing(d_(002)),grain stacking height(L_(c))and graphitization degree(g)of 0 and 0.05%(in mass)graphene modified EP CF are 0.343 nm,3.35 nm and 8.42%,0.342 nm,10.22 nm and 23.2%,respectively.In addition,graphene as a nucleation site affects the average cell size of EP CF.With the increase of graphene content,the average cell size of EP CF decreases firstly and then increases.Meanwhile,graphene increases the ordered structure of EP CF and improves its conductivity.When graphene is 0.05%(in mass),the conductivity of EP CF is 53.8 S·m^(–1).Compared with pure EP CF(compressive strain of 0.0096%),the compressive strains of 0.01%,0.02%,0.05%,and 0.1%(in mass)graphene modified EP CF increases to 0.208%,0.228%,0.187%,and 0.1146%,respectively.This study provides new research method for the preparation,carbon structure control,and properties of carbon nanomaterial/carbon foam.