The pore structure of expanded graphite and its characterization

doi:10.16085/j.issn.1000-6613.2017.02.029

Abstract

Abstract: The microstructure of expanded graphite(EG)has important influence on flexible graphite products,since EG is the raw material. An introduction of the macro-meso-micro pore distribution,pore size and pore shape in expanded graphite was made. The pore structure could be influenced by various factors,such as particle size,processes of oxidation and intercalation,degree of oxidation,water-washing,expansion fashion,crushing,etc. The basic principles of N₂ absorption isotherms,mercury instruction porosimetry,scanning electron microscope for structure characterizations were introduced. Advantages and disadvantages of small-angle X-ray scattering,atomic force microscope,DSC thermoporosimetry,NMR cryoporometry were also summarized. Furthermore,several suggestions of strengthening the study on meso-micro pore structure of expanded graphite and integrating various characterization methods were proposed for the further research of expanded graphite and its applications in other areas.

Key words: expanded graphite, microstructure, microscale, chemical processes, characterization method

摘要： 膨胀石墨是制备柔性石墨材料及相关制品的原料，其微观结构特性对柔性石墨制品有重要影响。本文简述了膨胀石墨中宏观-介观-微观多尺度的孔隙分布、孔隙尺寸、孔隙形貌等孔隙结构，论述了石墨粒度、氧化插层工艺、氧化程度、水洗工艺、膨化方式、破碎等加工处理对孔隙结构的影响，介绍了低温N₂吸附法、压汞法（MIP）、扫描电子显微镜（SEM）等膨胀石墨孔隙结构传统表征技术的基本原理，总结了小角度X射线散射法（SAXS）、原子力显微镜法（AFM）、差示扫描热孔计法（DSCT）、核磁共振冷孔计法（NMRC）等表征方法的优缺点，提出今后应结合多种表征技术重点探索膨胀石墨介微观孔隙结构，以此为切入点探讨膨胀石墨的理化性能，有助于推动膨胀石墨孔隙结构的深入研究及在其他领域的应用。

关键词: 膨胀石墨, 显微结构, 微尺度, 化学过程, 表征方法

CLC Number:

TD127.11

LUO Liqun, LIU Bin, AN Fengwen. The pore structure of expanded graphite and its characterization[J]. Chemical Industry and Engineering Progree, 2017, 36(02): 611-617.

罗立群, 刘斌, 安峰文. 膨胀石墨孔隙结构及表征方法研究进展[J]. 化工进展, 2017, 36(02): 611-617.

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