| 摘要 |
PURPOSE:To prepare a pitch which can be oxidized in a shorter time and produces carbon fiber having excellent spinnability and high strength, by performing 1st-step and 2nd-step heat treatments of a raw material pitch at specified temps. and pressures. CONSTITUTION:A raw material pitch obtained by removing soft oils from a petroleum residual oil, is subjected to a 1st-step heat treatment at 400-460 deg.C under pressure of 5-50mm.Hg and then to a 2nd-step heat treatment at 450- 500 deg.C under pressure of 0.1-5mm.Hg for 0.1-30min to produce a pitch having an optically anisotropic phase content of 80-100%, a pyridine insoluble content of 30-70wt%, a number-average M.W. of 1,000-1,400 and a softening point of 330- 380 deg.C. Preferred residual oils are those of catalytic cracking of pertroleum distillate and those of thermal cracking such as naphtha which have a high aromatic hydrocarbon content. |
