S-H. Hong et al. /Carbon 37(1999)917-930 1 5KU 点5K256 1的h ig. I.(continued to each other. No significant orientation was observed in ly a random transversal texture at low magnification the alignment of domains. The periphery of the insoluble 1g). The high magnification photograph of the microdomains in the extracted as-spun fiber appeared showed variable shape of domains of ca. 500-1000 nm much more sharp and twisted, compared with that of the ize(Fig. Ii). The shapes of domains exhibited curvature as-spun fiber, indicating that the removal of the soluble formed through the curved connection of microdomains fraction from the microdomain in the mesophase pitch The cross-sectional surface of fiber heat-treated at 2400oC modifies the shape of domains clearly exhibited the random transversal texture at low The fiber heat-treated at 1000.C showed macroscopical magnification( Fig. 1j). The domain shape of the fiber920 S.-H. Hong et al. / Carbon 37 (1999) 917 –930 Fig. 1. (continued) to each other. No significant orientation was observed in ly a random transversal texture at low magnification (Fig. the alignment of domains. The periphery of the insoluble 1g). The high magnification photograph of the fiber microdomains in the extracted as-spun fiber appeared showed variable shape of domains of ca. 500–1000 nm much more sharp and twisted, compared with that of the size (Fig. 1i). The shapes of domains exhibited curvature as-spun fiber, indicating that the removal of the soluble formed through the curved connection of microdomains. fraction from the microdomain in the mesophase pitch The cross-sectional surface of fiber heat-treated at 24008C modifies the shape of domains. clearly exhibited the random transversal texture at low The fiber heat-treated at 10008C showed macroscopical- magnification (Fig. 1j). The domain shape of the fiber