将石油系中间相沥青利用限定尺寸法发泡后获得了泡沫炭,泡沫炭再经氧化、炭化和石墨化处理获得了具有良好孔结构的泡沫炭.利用SEM和XRD分析了泡沫炭的形态和结构.发现调整发泡模具中的自由空间可以控制泡沫炭的孔径;炭化和石墨化后泡沫炭的孔径减小,孔壁片层取向接近石墨;泡沫炭的孔壁由平直孔壁和“Y”形孔壁结构成,前者内部片层取向优于后者.大孔径泡沫炭的孔壁具有更紧密的内部分子排列,但其微晶尺寸较小.
Green foams were prepared from a petroleum-derived mesophase pitch by using the size-restriction foaming method and the foams were further oxidized, carbonized and graphitized, consequently carbon foams with excellent cell structure were obtained. SEM and XRD were used to observe the morphologies and analyze the structures of foams. The results show that the cell size can be altered by controlling the free space in mold. During carbonization and consequently graphitization of foams, cell diameter reduces and the orientation of molecules in cell walls improves, approaching that of graphite. The walls of foam cells are built up by even ones and “Y” type junctions. The former has better molecular orientation than the latter. In is also found that the foam with large cells will have more close-grained molecular arrangement, but the crystallites in them are smaller.
参考文献
| [1] | Gallego N C, Klett J W. Carbon, 2003, 41: 1461-1466. [2] Klett J W, McMillan A D, Gallego N C, et al. Carbon, 2004, 42: 1849-1852. [3] Klett J W. Process for making carbon foam. US, Patent, 6033506, 2000. [4] Klett J, Hardy R, Romine E, et al. Carbon, 2000, 38: 953-973. [5] Watanabe F, Mochida I. Tanso, 2004, 212: 99-105. [6] Li K, Luan Z Q. New Carbon Materials, 2004, 49(1): 77-78. [7] Griffith G. Industrial Heating, 2002, 000(11): -E3-E3. [8] Umemoto K, Saito S. Physical Review B, 2001, 64(19): 193409-1-3. [9] Li T Q, Wang C Y, Liu X J, et al. Chinese Science Bulletin, 2004, 49(11): 1105-1110. |
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