Optically anisotropic pitch for manufacturing high compressive strength carbon fibers

摘要

An optically anisotropic pitch, which is suited for manufacturing particularly high compressive strength carbon fibers in a stable fashion, with satisfactory productivity and continuously is composed of a benzene soluble component (BS) and a benzene insoluble component (BI) and has a Q value (i.e., weight-average molecular weight divided by number-average molecular weight) of 1.6 or below, a number-average molecular weight ratio of the benzene soluble component to the benzene insoluble component of 2.5 or below, an aromatic carbon fraction factor (fa) of 0.8 or below, a C/H atomic ratio of 1.85 or below and an optically anisotropic phase of 90% or below.;A method of manufacturing high compressive strength carbon fibers using the optically anisotropic pitch involves melt spinning the aforesaid optically anisotropic pitch, infusibilizing the spun pitch fibers, and carbonizing or graphitizing the infusibilized fibers.