| 摘要 |
PURPOSE:To obtain the title impregnating pitch being inexpensive and having high stability at high temp. by allowing the pitch to contain a specified proportion of quinoline insolubles constituted of free carbon and spherical mesophase having a specified particle size range, and regulating a softening point of the pitch to be in a specified range. CONSTITUTION:A soft pitch (30-70 deg.C softening point) or a medium pitch (70-110 deg.C softening point) contg. 3-10wt.% free carbon is prepd. as starting material, and spherical mesophase having 10-15mum particle size is generated by heating the pitch at 350-500 deg.C in inert gas atmosphere such as N2. Then, the pitch contg. the generated mesophase is distilled under <=20mmHg reduced pressure in order to improve carbonization yield of the pitch to remove thus a low molecular weight fraction, and the softening point of the pitch is adjusted to 200-250 deg.C. Thus, an aimed impregnating pitch for producing a carbon composite material reinforced with carbon fiber is obtd. |
