| As an important type of natural graphite,cryptocrystalline graphite always be used in graphite electrodes and coatings because of its nano-scale size,good anisotropy,reactivity and mechanical properties.Due to the lack of evaluation methods for graphite content in cryptocrystalline graphite,about half of the cryptocrystalline graphite produced in China are used as coal fuels every year,which make a great waste of graphite resources;in addition,many foreign low-quality anthracite coals over our country's coal imports restricts in the form of graphite and use as fuel after they entered into China.They created an unnecessary impact on China's coal market.In this paper,based on Raman spectroscopy,the graphite content of anthracite-associated graphite was analyzed semi-quantitatively.On this basis,graphene-likesheets/epoxyresincompositeswerepreparedusing anthracite-associated graphite with lower graphite content,and the thermal conductivity of composites were studied.6 sets of standard samples with relatively known graphite content were prepared using high-purity graphite and standard anthracite.First-order Raman feature information of standard samples was studied based on confocal laser Raman spectroscopy,and at least 15 spectra of Raman peaks at different locations were obtained from every sample.The relationship between the Raman characteristic information of the standard samples and the graphite content was studied from the characteristic information data of each sample.The results showed that the statistics of the peak intensity,peak position,half-width,and peak area of the standard samples have a certain correspondence with the graphite content.With the graphite content increasing in the standard samples,the ratio of the peak intensity of the D peak to the G peak,the half width of the D peak and the G peak decreases substantially linearly;Within the range of graphite content,the peak position of D peak shows a clear trend of moving in the direction to high wave number,and the peak position of G peak shows the trend of moving in the direction to low wave number.The D-peak and G-peak in the first-order Raman spectra are relatively broad because of coal-based carbon materials are superimposed peaks.Based on the Raman spectrometer's own WiRE software,the D-peak and G-peak were fitted by Lorentz-Gaussian mixed-fitting model.Based on the statistics,the area of D peak and the total area of D and G peaks were studied.The ratio(A_D/(A_D+A_G))trended with the graphite content,and it was found that the overall trend showed a gradual downward trend;then,from each standard sample statistics,the median was taken and the top and bottom were 2 data,the average(A_D/(A_D+A_G))),the use of binary cubic equations(A_D/(A_D+A_G))the average value and graphite content of the corresponding relationship between the goodness of goodness reached 0.9984;This quantitative analysis of graphite content of anthracite associated graphite.Graphene-likesheetsarepreparedusingRamanspectroscopyand low-temperature heat treatment at temperatures between 500-650oC,using relatively low graphite content of anthracite-related graphite.The graphene-like sheets/epoxy resin composites were obtained.Its thermal conductivity was studied.The results of Raman spectroscopy showed that the quality of graphene-like sheets which prepared at 600?were best;the thermal conductivity of the composites showed a clear corresponding relationship with the amount of graphene-like sheets added,and the amount of graphene-like sheets added were in the range of 0-20 wt.%.With the increase of the graphene-like sheets content,the thermal diffusion coefficient and the thermal conductivity of the composites were basically linearly positively correlated.When the addition amount was 20 wt.%,the thermal conductivity of the composite was 86.2%higher than that of the pure epoxy resin. |
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