| 摘要 |
PURPOSE:A soft or medium coal pitch free from free carbon is heat-treated under specific conditions to form meso phase whereby a precursor pitch for high-performance carbon fiber is obtained, which has good fiber-forming properties with low viscosity and high homogeneity. CONSTITUTION:Coal tar is separated and treated to obtain soft pitch or medium pitch free from free carbon. The resultant pitch is combined with a hydrogenated hydrocarbon solvent such as tetralin or decalin, heat-treated at 350-450 deg.C under pressure of 10-40kg/cm<2>, then at 450-500 deg.C under reduced pressure of 0.1-10Torr to form mesophase. Thus, the objective precursor pitch is obtained, which is wholly composed of the single phase of optically anisotropic texture containing 20-60wt% of the fraction insoluble in quinoline.
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