Behavior of Meso-Carbon Microbeads in Quinoline

The behavior of meso-carbon microbeads in the boiling quinoline was investigated. The meso-carbon microbeads used were of three kinds; Type C, Type M and Type P. These were treated in quinoline at 238 •Ž for 30 min. and the insoluble part was filtered out. This procedure was repeated five times. The amount of quinoline soluble part was measured and the structural characteristics of quinoline insoluble part were examined by IR spectroscopy, X-ray diffraction and scanning electron microscopy. The following results were obtained. (1) Almost all amount of quinoline soluble part in the three types of the meso-carbon microbeads was extracted after the first treatment. Among the three types, the amount of quinoline soluble part was highest in type P. (2) The characteristics of the quinoline insoluble part in the meso-carbon microbeads determined by IR and X-ray analyses were not altered from those in the non-treated microbeads. However, the meso-carbon microbeads were found to have several cracks after treatment in quinoline. The cracks developed in three or four directions starting from the point corresponding to the position of pole in the mesophase spherule proposed by Taylor et al. From these results, it was suggested that the formation of cracks in the microbeads by the treatment in quinoline is due to the release of internal strain of lamellae near the pole.